posted 06-07-2002 02:20 PM            

Title: THz-Bandwidth, Deep Submicron, Regrown-Base
Transfer-Substrate HBTs

PI: Mark Rodwell
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA SANTA BARBARA
Department of Electrical and Computer
Engineering
Address: CHEADLE HALL RM 3227
Santa Barbara, CA 93106
(805) 893-3244
Funding Agency: Office of Naval Research
PR Number: 00PR00014-00
Award Number: N000149910041
Current End Date: 30-Sep-2001
Scientific Officer: John Zolper

Objective:
A low parasitic heterostructure bipolar transistor (LP-HBT) will be scaled down to an emitter width of 0.1 microns to achieve the first THz
transistor.
Approach:
A transfer substrate flip wafer process is being developed for a low
parasitic heterojunction bipolar transistor (LP-HBT) whereby the n-type
semiconductor under the p-type base contact region is removed to
dramatically reduce the base-collector capacitance. The structure will
be scaled down to a 0.1 micron emitter width that should produce the
first THz transistor. The work will employ an InP collector to improve the breakdown properties over previous devices.
Progress:
This program seeks to develop very high speed transistors (HBTs) using
a transferred-substrate technique. By scaling the devices to very
small dimensions, HBTs have been produced with power-gain cutoff
frequencies as high as 1080 GHz, 3.5:1 higher than any other HBT and
1.8:1 higher than any other kind of transistor. Efforts to obtain high
current-gain cutoff frequencies have resulted in a record 254 GHz ft,
and a number of wafers have been processed with the recent goal of
obtaining much higher ft.

Title: Piezoelectric Doping for GaN Heterojunction
Bipolar Transistors
PI: Peter Asbeck
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA SAN DIEGO 0934
Department of Electrical Engineering
Address: 9500 GILMAN DRIVE
La Jolla, CA 920930407
(619) 534-6713
Funding Agency: Office of Naval Research
PR Number: 00PR00026-00
Award Number: N000149810539
Current End Date: 31-Mar-2001
Scientific Officer: John Zolper

Objective:
Use strong piezoelectric effect in AlGaN/GaN layers grown in SiC to
achieve enhanced hole densities and thereby produce high power
heterostructure bipolar transistors in this material system.
Approach:
Holes densites on the order of 2e18 cm-3 will be generated in the
base of a AlGaN/GaN collector-up HBT grown on SiC. This will be
accomplished by growing a graded AlGaN layer in the base of the
transistor. The hole enhancement will first be studied in diode test
structures prior to complete HBT fabrication. Complete collector-up
HBTs will be fabricated and characterized at dc and microwave
frequencies. Following successful demonstration of the collector-up
HBT, novel designs will be implemented to reduce extrinsic emitter
injection either by ion implantation or selective area lateral
epitaxial overgrowth.
Progress:
Preliminary designs of the HBT has been developed. Material
structures have been specified and are ready for growth at partnering
institutions. Simulation studies of the hole concentration expected in
the base layer have been carried out based on the piezoelectric effect
and the incorporation of Mg acceptors. Stress relaxation in 3
dimensions has been studied in a finite element simulation, to
determine if the piezoelectric charge will be significantly modified at the edges of the devices. For the collector-up device, current confinement in the intrinsic emitter was studied. It was found that it is critical to minimize current spreading in the extrinsic emitter region. A novel structure for improvement in base contacts based on piezoelectric doping has been devised, and structures for potential implementation of the concept have been designed. Acceptor-like doping from spontaneous and piezoelectric polarization in AlGaN/GaN HBT
structures was theoretically evaluated. Experimental samples to
measure this doping (together with that from modulation doping using
Mg) were designed. After epitaxial growth at NCSU (Prof. R. Davis), the
samples were measured. Results confirm doping contributions of the
magnitude expected. Structures with n-type base regions (hot electron
transistors) have also been designed and are being fabricated.

Title: Materials Physics & Electron Transport
Issues in Superconducting Electronics
PI: Robert Buhrman
CORNELL UNIVERSITY
School of Applied & Engineering Physics
Address: 120 DAY HALL
ITHACA, NY 14853
(607) 255-3732
Funding Agency: Office of Naval Research
PR Number: 00PR00092-01
Award Number: N000149710142
Current End Date: 31-Oct-2002
Scientific Officer: Deborah Van Vechten

Objective:
To provide output from the PI's previous efforts regarding the cause and
remedies of inhomogeneous oxygen distribution in YBCO to applications
such as high performance HTS filters, high current density (Jc)
conductors, and HTS Josephson junctions wherein such inhomogenities
may deleteriously impact performance. Improved ability to apply HTS
materials to Navy problems should result.
Approach:
To collaborate with several other groups. Whether the 5-10x
improvement following ozone treatment of the Jc of large angle grain
boundaries is reproduced in the predominantly small angle case of IBAD
textured tape will be tested in conjunction with 3M and Stanford. The
impact of the same treatment on microwave surface loss and IP3 will be
tested at NIST. Details of the effect of ion beams on the surface of YBCO will be studied to look for both surface passivation coatings and
improved uniformity junction tunnel barriers. A small effort will look at normal metal barriers for NbN based junctions in order that we have a
self-shunted option for this higher temperature digital material.
Progress:
Inhomogeneous oxygenation produces variation in the superconducting properties of HTS materials and, if the material is used as a barrier in a Josephson junction structure, to non-reproducible tunneling characteristics. It is thus significant that doping, as with Co in
the most common barrier material, produces local stress fields that
reduce the oxygen binding energy and lead to inhomogeneous
concentrations. As a result only ozone annealing can produce full
oxygenation. When done to grain boundary and engineered interface
junctions, a Jc independent IcRn product results, a strong virtue. This
understanding should assist the development of improved HTS JJ. A
modified Blonder-Tinkham-Klapwijk model has been successfully used
to directly measure the interface scattering and spin polarization of
electrons traversing a clean ferromagnetic-superconductor interface.

Title: PLASMA WAVE ELECTRONICS DEVICE UTILIZING
TWO-DIMENSIONAL ELECTRON FLUID
PI: Michael Shur
RENSSELAER POLYTECHNIC INSTITUTE
Address: Thornton Hall
Charlottesville, VA 22903
(804) 942-4270
Funding Agency: Office of Naval Research
PR Number: 00PR00187-00
Award Number: N000149810210
Current End Date: 04-Jan-2001
Scientific Officer: John Zolper

Objective:
Develop theory and experimentally demonstrate the application of
the plasma wave properties of the two dimensional electron gas in high
mobility transistors as a high frequency detector.
Approach:
The non-linear theory will be developed for an arbitary load, for wide
bandgap semiconductors, for detectivity, and for the analysis of detector arrays. The experimental work will involve the design, fabrication, and characterization of non-resonant and resonant detectors, and for detector arrays.
Progress:
Investigations were performed on microwave GaN-based HEMT detectors
and, for the first time, terahertz GaAs-based HEMT detectors. Both
types of transistors operated at frequencies much higher than their
cutoff frequency. The gate voltage dependence is in good agreement
with the theory developed under the program. Polarization
dependencies were discovered. The measured temperature dependence
of the detector responsivity suggests a high viscosity of the electronic
fluid. A new theory was developed that predicts the dynamic range of
the terahertz HEMT detector.In the past year, we demonstrated
experimentally the first terahertz (2.5 THz) detector utilizing an
AlGaAs/GaAs High Electron Mobility Transistor (HEMT). The bias
dependence of the measured detector responsivity is in agreement with
the analytical detector theory. Also, this detector is sensitive to the
polarization of the terahertz radiation. We have performed modeling and
characterization of 0.25 micron GaN-based HEMTs including the noise
characteristics and the electron mobility since high-mobility samples are required for GaN terahertz detector fabrication. Theoretically, we have studied the detector large signal theory and the nonlinear detector
theory for an arbitrary load. We have also studied the influence of
scattering of carriers on the "shallow water wave instability" of the
surface plasma waves in a HEMT.

Title: Broadband Microwave Traveling Wave Power
Amplifiers
PI: Kevin Webb
PURDUE RESEARCH FOUNDATION
Department of Electrical Engineering
Address: Hovde Hall, 3rd Floor
West Lafayette, IN 47907
(317) 494-3373
Funding Agency: Office of Naval Research
PR Number: 00PR00192-00
Award Number: N000149810371
Current End Date: 30-Sep-1999
Scientific Officer: John Zolper

Objective:
To design and fabricate high power traveling wave amplifier circuits
using AlGaN/GaN transistors developed under the Cornell MURI. The
proposal is configured to parallel the MURI in time frame and option
structure.
Approach:
To perform detailed characterization of high power transistors developed under the Cornell MURI and to develop nonlinear models for these devices. These device models will then be used to design high power traveling wave amplifiers. Said amplifiers will be fabricated and tested under this contract.
Progress:
In collaboration with Prof. Eastman, et al., from Cornell, the PI has
designed high efficiency Class A traveling wave and distributed (compact) monolithic GaN HEMT amplifiers that have no drain line
dummy termination. These designs used a nonlinear HEMT model
derived from measured data. Forthcoming experimental data is expected
to support the design concept, which can then be transferred to a Class B push-pull design. Prior to achieving these designs, investigatations will be performed of fundamental issues related to broadband amplifiers and device models, including stability, matched terminations, drain and gate line matching, the basis and accuracy of the HEMT model, and physical implementation strategies. Fabrication of these amplifiers is underway at Cornell.

Title: Ultra-Linear Dynamically Programmable
Analog to Digital Converter
PI: Oleg Mukhanov
HYPRES INC
Address: 175 CLEARBROOK ROAD
ELMSFORD, NY 10523
(914) 592-1190
Funding Agency: Office of Naval Research
PR Number: 00PR00211-02
Award Number: N0001499C0089
Current End Date: 30-Dec-2000
Scientific Officer: Deborah Van Vechten

Objective:
Seek a dynamically programmable analog to digital converter wherein
the performance may be programmed from 19 effective bits of resolution
with 116 dB spur-free-dynamic-range (SFDR) at 20 MHz sampling speed
to 9 effective bits resolution with a 70 dB SFDR at 2 GS/s.
Approach:
Low transition temperature superconductors, in particular Nb, will be
used to fabricate the circuits using Rapid Single Flux Quantum (SFQ)
logic. All demonstrations to be done using liquid He cooling. A high-speed single bit quantizer will produce quantized pulses at a rate
dependent on the input signal current. The time at which these pulses
arrive at the synchronizer is resolved and determines the digital data
stream. Both on-chip superconductive decimation and ratio programmable room temperature decimation will be used to vary the sample speed and accuracy of the final samples. The work will increase the number of synchronizer elements and thus timing accuracy within a clock cycle and increase the clock speed of the current design. Perfection of chemical mechanical polishing, improved lithographic resolution of devices, and an increase in the speed of the interface to room temperature circuits is required for success.
Progress:
A complete 20 GHz ADC design was finished, including a new front-end
and a new digital filter. The circuit showed 20 GHz operation of the
separate ADC sections after the first design iteration, substantially
higher than the previous maximum of 13 GHz. A 25 GHz digital filter
design was completed and operated properly in a four-bit
implementation in the standard 3-um process. Room temperature
interface and decimination filtering components were successfully
tested up to 1 GS/s. Operation to 240 GHz was demonstrated in a toggle
flip-flop fabricated using SUNY's 1.5-um process. The in-house 1.5-um
process has demonstrated high-Jc 100 shunted-JJ arrays and the
conversion of digital cell library to this new process has begun.

Title: High Speed Analog to Digital Converter with
Large Dynamic Range & Programmable
PI: Joseph Jensen
HRL LABORATORIES LLC
Address: 3011 MALIBU CANYON ROAD
MALIBU, CA 90265
(310) 317-5250
Funding Agency: Office of Naval Research
PR Number: 00PR00237-00
Award Number: N0001499C0144
Current End Date: 08-Apr-2002
Scientific Officer: Deborah Van Vechten

Objective:
Continue development of Pi Sigma Delta analog to digital converters
demonstrated earlier using non ONR funding. This work will demonstrate the most critical component of an ADC, which, once finished, using lower technical risk components, is expected to meet the performance specifications expressed in the AMRFS BAA ONR 98-022 and so enable the concept of reconfigurable, multi-function receive apertures.
Approach:
Utilize a pi sigma delta analog-to-digital converter architecture
consisting of 8 separate delta-sigma-modulator channels employing 4th
order modulators clocked at 8GSPS. Different band width modes will
utilize different numbers of channels (the narrower the BW, the fewer
the channels). The modulator circuit sections will be implemented in
200 GHz fT, fmax low parasitic InP HBT IC technology. The decoder/ digital filter section required for a complete ADC will be
implemented in software and the measured data will be processed
off-line. A circuit layout database for the pi sigma delta-modulator
section will be created and two iterations of this section will be
fabricated, packaged in a commercially available high-speed package
and tested for functionality in beam steering receivers.
Progress:
Work on the detailed circuit plans began in late spring 1999. The
architecture planned uses a constellation of eight delta-sigma modulator
channels clocked at 8 GSPS and combined so that the errors
introduced by the modulators must be uncorrelated and cancel. A
mathematical model has been developed to allow behavioral simulation
of the planned continuous time DS modulators using conventional
discrete time simulation tools for the noise transfer function.

Title: The Effects of Impurities on Junction
Behavior in High-Temperature
PI: Michael Flatte
UNIVERSITY OF IOWA
Physics and Astronomy
Address: Iowa City, IO 522421479
(319) 335-0201
Funding Agency: Office of Naval Research
PR Number: 00PR00238-00
Award Number: N000149910313
Current End Date: 31-Dec-2001
Scientific Officer: Deborah Van Vechten

Objective:
Calculate the effect of different classes of impurities in the vicinity of free or interface surfaces on the behavior of superconductors and use
the calculational results to explain experimental results of other ONR
supported researchers.
Approach:
Apply the calculational approach for interface electronic structure
developed under the previous ONR grant to calculate the supercurrent
transport through arbitrary transparency junctions, the effect of strong
and potentially time-dependent impurities such as uncompensated spin
copper atoms, identify signatures in the IV curves of oxygen vacancies
and excess concentration of cobalt atoms. Also include complexity of
proper multi-band tight binding models of the band structure into the
calculations.
Progress:
Parametrized versions of multiple electronic bands were included into
the calculations of impurity effects on junction behavior. Good
correspondence was found with STM measurements by J. C. Davis on
impure BSCCO. Work to include the CuO chains also found in YBCO
are mostly done and supercomputer time for these more complex
calculations has been secured.

Title: EXPERIMENTS ON SUPERCONDUCTIVITY AT
MICROWAVE AND RADIO FREQUENCIES
PI: Nai-Phuan Ong
THE TRUSTEES OF PRINCETON UNIVERSITY
Physics Dept.
Address: FIFTH FLOOR NEW SOUTH BUILDING
Princeton, NJ 085440636
(609) 248-4347
Funding Agency: Office of Naval Research
PR Number: 00PR00239-00
Award Number: N000149810081
Current End Date: 30-Sep-2000
Scientific Officer: Deborah Van Vechten

Objective:
To understand the systematics of the truly inherent effects which occur
when high temperature superconductors are subjected to simultaneous
dc magnetic fields B and rf signals. The plasma resonance(perpendicular to the ab planes) phenomena will be evaluated for use as an absorption based sensor in the 30-300 GHz range. The basic nature of the photon detection process will be clarified by distinguishing thermal conduction by phonons and quasiparticles. An improved scanning microwave absorption probe will allow vortex pinning sites to be unambiguously identified and correlated to the sites of excess energy dissipation in thin film resonators supplied by Lucent Technologies. The work will improve our understanding of the HTS materials and our ability to build low loss, high power transmit, as well as receive, rf filters and more efficient microwave sensors.
Approach:
The experiments utilizing tilted magnetic fields to demonstrate the
existence of plasma resonances will be extended up to 100 GHz and to
lower temperatures using cavity techniques and Bi 2212. The determinants of the width and intensity of the resonance will be the chief focus. The same crystals will be used to investigate phonon vs. quasiparticle heat conduction near the phase transition (B field dependent) recently discovered by the PI. A near field scanning microwave absorption sensor will be constructed to operate in the 10-20 GHz range and used to explore the surface of untwinned YBCO crystals and films and submicron spheres of superconductors. This work will be correlated to work of ONR supported theorists. The device will also be used to improve the understanding of losses in YBCO rf filters in the 1-40 GHz band and could help improve tunnel barriers in the ramp edge Josephson junctions used in HTS digital logic.
Progress:
Detailed field dependence measurements of the thermal conductivity of YBCO have allowed unambiguous separation of the electronic and
phononic contributions. The derived quasiparticle (electronic) mean free path increases smoothly from 0.1 micron at 90K to 0.5 micron at 10K. A scanned 25 to 110 GHz microwave spectrometer has been constructed and used to observe for the first time antiferromagnetic (AF) resonance lines in a manganite and cyclotron resonance in a 2D electron gas (GaAs-AlGaAs).

Title: Expansion of Josephson Effect & Macroscopic
Quantum Interference in Superfluid 3He
PI: James Davis
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA BERKELEY
Department of Physics
Address: 366 Le Conte Hall
Berkeley, CA 94720
(510) 642-4505
Funding Agency: Office of Naval Research
PR Number: 00PR00240-00
Award Number: N000149411008
Current End Date: 30-Sep-2000
Scientific Officer: Deborah Van Vechten

Objective:
To complete a proof of concept demonstration of a superfluid quantum interference gyroscope having rotational sensitivity approaching 10^-9 of the earth's rotation rate. The goal of the expansion is to improve likelihood of successful completion of N00014-94-1-1008 which is developing a gyroscope predicted to have orders of magnitude with greater sensitivity than any existing unit.
Approach:
A toroidal shaped container, ultimately measuring a meter in diameter, will be micromachined in Si and interrupted symmetrically by arrays of 0.1 micron pores through a Si3N4 membranes placed across the ring. At each pore the superfluid mass flow equivalent of the Josephson effect in Dayem bridges will be manifested as a phase dependent difference in the flow rates between the arms, induced by the rotation of the torus. By measuring the critical current of 3He flowing in this system of channels, eventually with 1 part in 10^4 accuracy, the rotational phase contribution can be determined. This Sagnac effect should allow the rotational rate of the Earth to be determined. The approach of the expansion is to fund supply of cryogens more adequately so that actual experiments can be conducted for 8 months a year rather than only the 4 month allowed by current funding levels.
Progress:
The similarities and differences of superfluid 3He and superconducting
Josephson junction were investigated: both display Fiske and Shapiro
effects and the Current-Phase relation depends on sin (phase difference)
near Tc. However, discrepancies appear at low temperatures and the
superfluid case displays two intrinsic dissipation processes. Completion of a rotating cryostat and improved acoustic isolation chamber will enhanced the sensitivity of the gryoscope to be demonstrated early in fy00.

Title: FUNDAMENTAL PROCESSES IN SUPERCONDUCTING
NANOSTRUCTURES
PI: Michael Tinkham
THE PRESIDENT AND FELLOWS OF HARVARD
COLLEGE
Department of Physics
Address: Pierce Hall
Cambridge, MA 02138
(617) 495-3735
Funding Agency: Office of Naval Research
PR Number: 00PR00241-00
Award Number: N000149610108
Current End Date: 31-Oct-2001
Scientific Officer: Deborah Van Vechten

Objective:
To understand the physics that determines the behavior of Single
Electron tunneling Transistors (SET) and to work issues such as their
connections to the outside world and operating temperatures which will
effect their device applicability. These devices have features less than
100 nm in size in 2 if not 3 directions and are dominated by quantum
mechanical effects. One dimensional strings of nanoparticles offer the
possibility of elevated temperature operation and in any case appropriate size scale leads must be provided. Ultra small grains are
revealing for the first time ever the detail of many particle energy states. Andreev reflection is visible and important to the tunneling process in superconducting SET. SET are still in their early stages of development but they are expected to be important in the mid term once commercial drivers push main stream solid state electronics into this size scale. The physics they reveal could halt the historic trend in electronics to smaller and smaller scale devices.
Approach:
In the smallest grains investigated, both the single particle (electron)
energy levels and their perturbations due to the other electrons are
directly observable for the first time. Using techniques of self-assembly, it is possible to string together tens of nanoparticles. Doing so allows a single set of electrodes to control a larger signal and thus allows higher temperature operation despite thermal noise. Carbon nanotubes are also being explored as growth templates for direct deposition of wiring in SET circuits and for the physics they exemplify. Superconducting SET continue to be studied in the context of what they reveal about Andreev scattering, a critical effect in the push for new HTS devices.
Progress:
Extremely small size devices have different electrical performance. Wires 50% smaller in diameter (10 nm) than previously reported displayed a 10^3 wider resistive transition and non-zero residual resistance. This
places a lower bound on superconducting wire size. A record charge
sensitivity of 10-5 e/Hz has been achieved at 100 kHz in a 1 MHz
bandwidth in a cryogenic electrometer. The physics of lightning was
used to assemble conducting micron-long chains of ~30 nm diameter
particles.

Title: SUPERCONDUCTORS IN AN EXTERNAL FIELD
PI: Vladmir Kresin
U S DEPARTMENT OF ENERGY OAKLAND
OPERATIONS OFFICE
Department of Energy
Address: 1 CYCLOTRON ROAD, MS90-1070
BERKELEY, CA 94720
(510) 486-4126
Funding Agency: Office of Naval Research
PR Number: 00PR00242-00
Award Number: N0001498F0052
Current End Date: 30-Oct-2000
Scientific Officer: Deborah Van Vechten

Objective:
To develop and validate by direct comparison to experimental data a
detailed, predictive theory of the high temperature superconductors
(HTS). Specifically the role of spin-flip scattering in determining the
microwave surface resistance and energy relaxation processes, the
mechanism of photoinduced superconductivity, and the importance of
'electronic sound'. The first three topics are directly relevant to
improving the performance of these HTS materials in high performance
filters, an important Navy application.
Approach:
Work directly with experimentalists in trying to model the effects
observed. The PI has developed a model whereby spin-flipping scattering
by magnetic impurities becomes frustrated when the directions of the
individual moments becomes correlated. This model will be extended to
predict microwave surface resistance and comparison made to data from
Wuppertal on the dependence of (and especially reduction in) Rs on
applied magnetic field. The role of magnetic scattering on the energy
relaxation process which follows high energy absorption events will be
investigated jointly with 3 other theorists. The mechanism of long term
photoinduced superconductivity will be modeled in conjunction with
European researchers. Work will also proceed on the issue of explaining
existing heat capacity measurements in terms of the unusual plasmon
excitation spectrum caused in part by the anisotropy of the HTS materials. It is anticipated that when NRL experimentalists complete
measurements of proximity effect samples of HTS and LTS or
semiconducting materials, an active exchange will follow.
Progress:
Earlier models of the IV of step-edge junctions were successfully
generalized to deal with the less damaged interface of bicrystal grain
boundary junctions. The effect of an inhomogeneous distribution of
critical temperatures on the collective behavior of devices was analyzed
and used to explain why overdoped Tl-based cuprates display the
magnetic and resistive signatures of superconductivity at different
temperatures. The unusual superconducting properties of the
borocarbides were understood.

Title: A Microscopic Description of the Josephson
Junction Interface
PI: James Freericks
GEORGETOWN UNIVERSITY
Physics Department
Address: 37th & O Streets
Washington, DC 20057
(202) 687-6159
Funding Agency: Office of Naval Research
PR Number: 00PR00243-00
Award Number: N000149910328
Current End Date: 30-Dec-2002
Scientific Officer: Deborah Van Vechten

Objective:
Historically the tunnel barriers of superconducting Josephson junctions
have been selected in terms of the fabrication compatibility with the
superconductor - no chemical reactivity or interdiffusion, stability at
process temperatures, flatness of layers - and simple measures of its
electrical properties, especially the resistivity. This approach has not yet worked well for the high transition temperature materials. This award seeks to actually model from first principles electrical transport through a barrier for a variety of materials which are insulating for different physical reasons and to do this for both s and d wave (LTS and HTS) superconductors. Once complete, this work will provide important
guidance as to how to select the most appropriate barrier for HTS JJ,
important information if the HTS materials are to be applied to Navy
relevant high performance signal processing requirements in advanced
systems such as AMRFS.
Approach:
A microscopic lattice model for charge transport which averages over the
planes parallel to the interfaces that define the Josephson junction and
retains the perpendicular to the interface variation is to be developed.
The model will be solved numerically to determine the critical current
and the junction resistance. The solution will use either dynamical
mean-field theory or more sophisticated methods such as the dynamical
cluster approximation depending on the locality of the fluctuations. The
model parameters (electron density, electron-electron interaction
strength, bandwidth, etc.) and the types of interface (semiconductor,
Mott insulator, polaronic insulator, antiferromagnetic insulator, Kondo
insulator, etc.) will be varied to determine how to optimize the properties of the Josephson junction for both s and d wave superconductors.
Progress:
Successfully developed algorithms to predict the temperature
dependence of the critical current from the phase difference between
the superconductors and the junction resistance. The code (which uses
fast continued-fraction representations inmomentum space) is over two
orders of magnitude more computationally efficient than conventional
Bogliubov-Degennes methods. Testing for doped semiconductor barriers
nearly complete; comparison to experiment on InAs devices arranged.

Title: Optimization of Jc in BSCCO Tapes
PI: Eric Hellstrom
THE BOARD OF REGENTS OF THE UNIVERSITY
OF WISCONSIN
Dept of Materials Sci & Engineering
Address: 750 UNIVERSITY AVENUE
MADISON, WI 53706
(608) 263-9462
Funding Agency: Office of Naval Research
PR Number: 00PR00244-00
Award Number: N000149910323
Current End Date: 30-Jun-2000
Scientific Officer: Deborah Van Vechten

Objective:
The critical current density of long conductors made of BSCCO 2212
superconductors is much lower than that of short wires. The reason is
hypothesized to be the difficulty in achieving interconnected and
properly aligned 2212 grains from a melt whose composition is in the
single phase regime - the 2212 phase melts incongruently. The goal of
this work is to see if starting compositions in the "primary phase" regime (from whose melt 2212 phase crystals form directly) will end up
producing well oriented, interconnected assemblies of grains that can
support high current density, even though second phase species will
necessarily be present. Power applications of HTS materials will be
enabled by the work.
Approach:
Prepare powders with several compositions within the primary phase
regime and determine the reaction, liquification and solidification
temperatures using thermo-gravimetric analysis. Use quench studies
and SEM analysis to monitor the phase evolution and homogeneity of
the finished tape. Compare to conventionally processed tapes.

Title: A Cryogenic Loop for Cooling
Spatially-Separate Electronics Components
PI: Reza Shekarriz
ADVANCED THERMAL AND ENVIRONMENTAL
CONCEPTS INC
Address: 11890 Old Baltimore Pike
Beltsville, MD 207050000
(301) 931-1449
Funding Agency: Office of Naval Research
PR Number: 00PR00245-02
Award Number: N0001499C0145
Current End Date: 15-Jun-2000
Scientific Officer: Deborah Van Vechten

Objective:
To determine if electro-hydro-dynamical pumping (EHD) can provide the
fluid drive required to realize spatially localized cryogenic cooling via substrate channels for both superconducting and optimized semi-conducting chips. Performance goals are 0.1 to 10 W of heat lift at
70-80K and low electromagnetic noise. If successful, the use of high
performance cryogenic filters and digital signal processors in spatially
constrained settings (such as AMRFS receive arrays) and in close
physical proximity to electronics not requiring cooling will be enabled.
This will help the Navy derive benefit from the significant advantages
these devices offer.
Approach:
Conduct a feasibility study by constructing a model heat loop in the
laboratory which utilizes EHD electrodes in MEMs scale channels as the
pump. Test its cooling capacity against an electrical heater as a function of drive voltage in the 0-10V range using nitrogen as a single phase liquid and gas and as a fluid which evaporates at the site to be cooled. Determine the heat lift available and the electromagnetic noise created by the flow.
Progress:
The prototype pump has been designed and tested at room temperature
using a laboratory standard fluid. Plans for testing at GSFC with liquid nitrogen and at low temperatures are well advanced.

Title: SPIN INJECTION AT FERROMAGNET -
SEMICONDUCTOR AND FERROMAGNET -
SUPERCONDUCTOR INTERFACES
PI: Mark Johnson
NAVAL RESEARCH LABORATORY
Materials Science and Technology
Division
Address: 4555 Overlook Avenue SW
Washington, DC 203755320
(202) 404-8485
Funding Agency: Office of Naval Research
PR Number: 00PR00246-01
Award Number: N0001400WR20011
Current End Date: 30-Sep-2000
Scientific Officer: Deborah Van Vechten

Objective:
Work is needed to increase the on-state resistance of an individual
mesoscopic magnetoquenched superconducting valve if the read-out of
stored value is to be a simple to implement operation. These MMSV may
be useful as dense, low power, non-volatile and rad hard memory for
superconducting digital circuits if this problem can be solved. Currently the lack of memory with these characteristics forces superconducting logic circuits to utilize semiconducting memory which cannot be located in close proximity to the processors or very small (<4 KB), superconducting memories. Superconducting circuits could thus
become much more functional and useful in Naval receivers.
Approach:
Use N metal overlayer to tune the Tc of the superconducting stripe
driven normal by the fringing B field closer to the bias temperature of
the memory element. Doing that should increase the volume driven
normal in the on state and thereby the resistance in normal state.
Progress:
Development of the Mesoscopic Magnetoquenched Superconducting
Valve (MMSV) device is continuing. Initial Nb samples show a factor of 2 suppression of Ic at 4K which can be made much larger by decreasing
the bridge's Tc. Other devices demonstrated switching of the spin
polarization by current pulses in write wires and a two magnetic layer
variant that has higher potential packing density than the 1 layer
projected 1 Mbyte per cm2. Designs are complete for switching speed
testing at HYPRES.

Title: Doped SrTi03 Films for Josephson
PI: John Price
THE REGENTS OF THE UNIVERSITY OF
COLORADO
Department of Physics
Address: 206 armory Campus
Boulder, CO 803090019
(303) 492-2484
Funding Agency: Office of Naval Research
PR Number: 00PR00247-00
Award Number: N000149910360
Current End Date: 31-May-2002
Scientific Officer: Deborah Van Vechten

Objective:
SrTiO3 (STO) can be shifted from an insulator to a low carrier density
(super) conductor by doping with Nb. While pure STO is studied in thin
film form due to the utility as its voltage tunable dielectric constant, the doped form is a potential tunnel barrier for YBCO based HTS Josephson junctions. The goal of this award is to test the latter application -an improved junction fabrication process, especially an improved tunnel barrier- which is required if the highly useful digital applications superconductivity enables are to be realized at temperatures much above 10K.
Approach:
A previous ONR award explored the dopant dependent properties of
Nb:STO and learned how to make the films reproducible. This award will
develop an SNS HTS junction technology based on YBCO/Nb:STO/YBCO trilayers (which could be etched to define junctions in processes paralleling that of Nb/AlOx/Nb trilayers in LTS) and bilayers (which defines the junction by removing S material). This approach will utilize the low defect density and extreme stability, even to oxygen loss, of Nb:STO and its excellent epitaxial compatibility with both YBCO and substrate materials. Material will be deposited at U Colorado and, in some cases, finished into junctions as part of collaborations with NIST (Benz, Ono) and others who are expert in HTS JJ fabrication and test. Another collaboration with Freericks at Georgetown will help define the physics of tunneling using single devices that can be made to undergo the metal insulator transition and some work will be done to look at FET
style devices using bilayer samples.
Progress:
Nb-doped strontium titanate thin films may enable nm scale bilayer HTS
Jospehson junction fabrication. Nb doping the target controllably
produces metallic films: carrier concentrations > 1?1019 cm-3 and
mobility > 70 cm2/Vs. Ar was added to the deposition system to improve
the uniformity of ion bombardment. Hc2T(T) measurements indicate the
material is a very low carrier density s wave superconductor, as well as
the first example of a thermodynamically stable and field depletable
superconductor.

Title: RESONANT QUANTUM EXCITATION IN OXIDE
SUPERCONDUCTORS
PI: T. Venkatesan
UNIVERSITY OF MARYLAND AT COLLEGE PARK
Department of Physics
Address: College Park, MD 20742
(301) 405-7320
Funding Agency: Office of Naval Research
PR Number: 00PR00248-00
Award Number: N000149810284
Current End Date: 28-Feb-2000
Scientific Officer: Deborah Van Vechten

Objective:
To shed experimental light on the relationship between the structure
and chemical constituents of the unit cell in real samples (with defects) and the appearance of superconductivity in the high transition
temperature materials. The resonant response to optical absorption will
be utilized.
Approach:
To determine whether the recently observed, frequency dependent,
enhanced pair-breaking following photon absorption is a true resonant
phenomena in YBCO. Then formulate a model of the effect which
identifies the causal structural and compositional features and test
using other superconductors.
Progress:
Temperature dependent fine structure in the pair breaking resonance
has been detected. The spacing appears to correspond to that expected
from antiferromagnetic fluctuations in oxygen depleted regions. The
current hypothesis is that the term is from the electronic density phase
segregation known as stripes. This hypothesis will be evaluated in the
renewal effort.

Title: Lumped Josephson Junction Arrays for High
Performance Communication, Networking, and
Radar
PI: Samuel Benz
U S DEPARTMENT OF COMMERCE NATIONAL
INSTITUTE OF STANDARDS AND TECHNOLOGY
Electromagnetic Technology Division
Address: 325 BROADWAY
BOULDER, CO 80303
(303) 497-5258
Funding Agency: Office of Naval Research
PR Number: 00PR00249-00
Award Number: N0001499F0042
Current End Date: 30-Sep-2000
Scientific Officer: Deborah Van Vechten

Objective:
Develop the ability to fabricate an electrically "lumped" series array of superconducting Josephson junctions that will enable a super-conducting digital-to-analog converter capable of directly
generating arbitrary wave forms with useful voltage amplitudes and
phase noise low enough to be useful in Doppler radar. Such units are
expected to be able to operate over the range of carrier frequencies and
functionalities appropriate to AMRFS. "Distributed" arrays display
greater frequency sensitivity and generally poorer performance,
especially in regard to the maximum voltage swing.
Approach:
To act as a lumped element at 20 GHz, the array must occupy less than
2 x 2 microns. Yet to produce by itself a 1 V signal amplitude, that area must contain of the order of 30,000 junctions that work together to
produce over 10^14 SFQ pulses per second. Ramp edge HTS junctions
are impossibly large. Arrays with a variety of junction spacings will be
produced in HTS using both electron and ion beam damage at
Cambridge University (separate ONR award). LTS versions using from
Nb/PdAu bilayers and e beam written lithography could be made at
NIST if essential. Junction uniformity, interactions, and suitability for application to the DAC will be investigated.
Progress:
A focused ion beam is being used to etch arrays of superconductor-normal metal-superconductor junctions by controllably removing a portions of the top layer of S every 200 nm or less. Small arrays have been fabricated and delivered to NIST using Nb/PdAu bilyers. More complex coupling effects appear for spacings <~150nm. The reproducibly high-quality junctions showed Josephson coupling which scaled qualitatively with barrier properties and temperature as expected.

Title: HTS Lumped Josephson Junction Arrays for
High Performance Communication, Networking
and Radar
PI: Mark Blamire
UNIVERSITY OF CAMBRIDGE
Department of Materials Science and
Metallurgy
Funding Agency: Office of Naval Research
PR Number: 00PR00250-00
Award Number: N000149910146
Current End Date: 30-Nov-2000
Scientific Officer: Deborah Van Vechten

Objective:
Develop the ability to fabricate an electrically "lumped" series array of superconducting Josephson junctions that will enable a super-conducting digital-to-analog converter capable of directly
generating arbitrary wave forms with useful voltage amplitudes and
phase noise low enough to be useful in Doppler radar. Such units are
expected to be able to operate over the range of carrier frequencies and
functionalities appropriate to AMRFS. "Distributed" arrays display
greater frequency sensitivity and generally poorer performance,
especially in regards to the maximum voltage swing.
Approach:
To act as a lumped element at 20 GHz, the array must occupy less than
2 x 2 microns. Yet to produce by itself a 1 V signal amplitude, that area must contain of the order of 30,000 junctions that work together to
produce over 10^14 SFQ pulses per second. In this work arrays with a
variety of the repeat distances between junctions below 100 nm will be
produced in HTS using both electron and ion beam damage. Junction
uniformity, independence of operations, and suitability for application to the DAC will be investigated.
Progress:
A focused ion beam is being used to etch arrays of superconductor-normal metal-superconductor junctions by controllably removing a portions of the top layer of S every 200 nm or less. Small arrays have been fabricated and delivered to NIST using Nb/PdAu bilyers. More complex coupling effects appear for spacings <~150nm. The reproducibly high-quality junctions showed Josephson coupling which scaled qualitatively with barrier properties and temperature as expected.

Title: HIGH-RESOLUTION ANGLE - AND SPIN-RESOLUTION
PHOTOEMISSION STUDIES OF INTERFACE ISSUES
OF MAGNETIC AND SUPERCONDUCTING MATERIALS
PI: Zhixun Shen
THE BOARD OF TRUSTEES OF THE LELAND
STANFORD JUNIOR UNIVERSITY
Sponsored Projects
Address: 125 PANAMA ST JORDAN QUAD BIRCH
Stanford, CA 943054055
(415) 723-4659
Funding Agency: Office of Naval Research
PR Number: 00PR00251-00
Award Number: N000149810195
Current End Date: 30-Sep-2000
Scientific Officer: Deborah Van Vechten

Objective:
To improve our understanding of the surface physics of both high
temperature superconductors and magnetic materials and the interfaces
which form when they are layered on one another. For the magnetic
materials, the goal is to determine the angle and spin resolved density of states in the magnetic state and understand how these impact the
transport of spin polarized current into overlayers of normal metals.
Superconducting materials will then be added to form spin current
sensing devices. A second effort will look at the viability of stabilizing the surface states revealed by low temperature cleaving by gaseous passivation. If successful, this could lead to the development of ways of avoiding degraded surface layers in fabricating HTS structures such as the Josephson junctions used in digital electronics. The former effort is part of the DRI on spin-injection devices. Improvements in the quality of circuits delivered to Navy applications requiring high performance electronics such as ship self defense and AMRFS is predicted.
Approach:
To fabricate extremely high quality samples and measure them
extremely accurately. The magnetic/normal metal work will be done by
taking high quality single crystals such as Ni and Co, cleaning the
surface well, and depositing layers of Cu, Ag, and Au (different
spin-orbit scattering) a few atomic layer thick on top. These would then
be measured with angle resolved photo-emission (APRES) having 4 meV
energy resolution, LEED, and STM in-situ with the deposition at a new
facility at the Advanced Light Source. SMOKE will be used to measure
the magnetic properties. The surface passivation work has already
shown there is a disordering of the well-order bare surface as the
temperature is raised. By adding gases to the cleavage chamber and
monitoring using ARPES as the temperature is changed, the chemical
shifts caused by the adsorbate can be deduced. If any are found that
substantially delay the onset of disorder (H is similarly used to passivate dangling bonds in amorphous Si), then industrial contacts will be solicited to intentionally add the reactive species to the deposition
environment near the end and after the deposition. Questions to be
answered are whether, and how uniformly, the gas is incorporated and
with what effect on the electrical properties of subsequently processed
devices. The structure of "engineered interfaces" (intentionally oxygen
depleted) will also be determined.
Progress:
The technical problems of introducing ozone into a UHV environment
have been solved to the point where degradation of a newly exposed
YBCO surface by contaminant water and CO2 is mostly under control.
This is a necessary first step toward being able to detect the shifts in
surface oxygen states using ARPES and to study potential YBCO
passivation structures, the goal of this work.

Title: Growth & Microwave Studies of Nonlinear
Dielectric Films for Tunable High
Temperature Superconductor Microwave
Electronics
PI: Charles Rogers
THE REGENTS OF THE UNIVERSITY OF
COLORADO
Dept of Physics
Address: Boulder, CO 803090019
(303) 492-4476

Funding Agency: Office of Naval Research
PR Number: 00PR00252-00
Award Number: N000149710141
Current End Date: 30-Sep-2002
Scientific Officer: Deborah Van Vechten

Objective:
To enable thin-film capacitors with wide tuning (>30%) and dielectric
loss tangents below 2 x 10-4, an order of magnitude better than achieved today. In combination with the small fields required to tune (1 V/mm) STO, these properties will enable wide-band tunable filters and other microwave circuit elements of interest to the Navy in systems such
as AMRFS.
Approach:
The origin of dielectric losses in STO thin films will be understood via a systematic study of film growth conditions, liftoff processes, and their impact on microwave dielectric response. In addition to these processing studies, the dielectric response dependence on temperature, electric field and applied strain will be studied.
Progress:
Efforts have focused on improving the dielectric properties of STO via
optimization of growth conditions and monitoring using in situ optical
ellipsometry. The resultant STO films on LAO substrates have the
highest dielectric tuning and lowest microwave losses ever reported at
microwave frequencies. A method for lifting-off epitaxial films of STO
was developed that produced films with twice as large dielectric tuning
as the best films on LAO and approaching those observed in bulk STO
crystal. The existence of In situ optics allows more rapid reoptimi-zation of growth conditions when chamber instrumentation is altered and
essentially needs recalibration.

Title: Expansion of "Demonstrations of
Ultra-High-Speed and Dense Circuits using
Unique Nb IC Fabrication�
PI: Theodore Van Duzer
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA BERKELEY
Regents/Sponsored Projects
Address: 336 Sproul Hall
Berkeley, CA 94720
( 51) 064-3306
Funding Agency: Office of Naval Research
PR Number: 00PR00308-02
Award Number: N000140010003
Current End Date: 30-Sep-2002
Scientific Officer: Deborah Van Vechten

Objective:
Will advance state-of-the-art in digital superconducting electronics both in regard to processing speed of minimal sized ADC and ability to realize complex circuits. The clock speed aspect will include fabrication using UCB demonstrated output 10 GHz amplifiers and 10 fold larger Jc devices of circuits designed at Northrop Grumman to provide
performance well beyond the Walden curve needed in systems such as
AMRFS. The complex circuit will initially be the digital SQUID of
SUNY-SB which is expected to strongly enable the application of
SQUIDs to medicine, especially heart disease detection, by eliminating
the costly (>$1M) need for a magnetically shielded testing environment.
Approach:
This work will confirm the high device quality possible with an
NbN/TaN/NbN layer structure and measure the spread in junction
parameters. Since they have much thicker barriers, achieving the <2%
parameter spreads needed to yield a functional circuit is expected to be
easier than for the currently standard device structure.

Title: Noise and Superconducting Devices
PI: Clare Yu
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA IRVINE
Dept. of Physics & Astronomy
Address: 115 ADMINISTRATION BUILDING
IRVINE, CA 92717
(949) 824-6216
Funding Agency: Office of Naval Research
PR Number: 00PR00309-00
Award Number: N000140010005
Current End Date: 30-Oct-2003
Scientific Officer: Deborah Van Vechten

Objective:
Electrical noise in the circuit is the factor which limits the detection
range and sensitivity of SQUID sensor based systems such as the unexploded ordnance finding system of NCSC-Panama City. At the other extreme of frequency, phase noise may limit the functionality of high speed digital systems. This award will devise ways to remove the current error of factors of 10 or more from predictions of noise performance based on fundamental theory and provide guidance to improving performance.
Approach:
This small scale effort will start by reviewing the literature on noise in SQUIDs and simulations of bit error rates and other manifestations of
digital phase noise. Then the theoretical literature will be surveyed to
find the most relevant fundamental research. Finally these existing
theories will be combined to produce a predictive model and the result
compared to existing noise data.

Title: Microwave Losses in Tunable Device
PI: S. Sridhar
NORTHEASTERN UNIVERSITY
Distinguished Professor of Physics
Address: Physics Dept
Boston,, MA 02115
(617) 373-2930
Funding Agency: Office of Naval Research
PR Number: 00PR00310-00
Award Number: N000140010002
Current End Date: 30-Sep-2002
Scientific Officer: Deborah Van Vechten

Objective:
To increase the performance advantage of superconducting rf filters by
testing a magnetic loss hypothesis and, if proven, frustrating the loss
mechanism. The resultant materials improvement will make such HTS filters the obvious candidates for use in Navy multifunction rf systems
such as AMRFS.
Approach:
The possible relationship between microwave loss and non-linear
behavior and the motion of fluctuating localized regions of antifer-romagnetic order within globally superconducting samples will be
explored. If a causal relationship is proven to exists, methods of
reducing the undesirable behavior will be devised.

Title: Process Development for High Speed
Superconductor Logic
PI: James Lukens
THE RESEARCH FOUNDATION OF THE STATE
UNIVERSITY OF NEW YORK AT STONY BROOK
Department of Physics
Address: W-5510 MELVILLE LIBRARY
STONY BROOK, NY 117943300
(516) 632-8081
Funding Agency: Office of Naval Research
PR Number: 00PR00319-00
Award Number: N000149910374
Current End Date: 28-Feb-2002
Scientific Officer: Deborah Van Vechten

Objective:
To dramatically increase the clock speed at which moderately complex
Nb Josephson junction circuits have been demonstrated to operate. The
world's record circuit speed of 770 GHz, ~10X the fastest demonstrated
semiconductor circuit, was done for a quite simple divide-by-2 circuit.
Success in this effort will allow technology transfer to industry and an
increase in clock speeds from about 15 GHz today for useful circuits
such as ADC to about 100 GHz. Once there, they will be of great utility
to systems such as AMRFS that want to process wide ranges of the
electromagnetic spectrum at one time and without any frequency
down-conversion.
Approach:
To improve the process spreads and design rules as the linewidth is
shrunk first to 1.5 microns and then 0.8 microns, and finally to 0.5 or
less. At each stage work to increase the complexity of the circuit
demonstrated without deteriorating the yield.
Progress:
The initial goal of the ADC critical components demonstration has been
defined to use junctions 1 micron on a side. The resultant devices will
have junction areas nearly an order of magnitude smaller that those
made with present HYPRES technology. Initial discussions of design
rules were conducted and an initial fabrication run this summer at
Stony Brook based on HYPRES circuit layouts planned.

Title: Ka-band HBT Phased Array Technology
PI: Marko Afendykiw
NAVAL AIR WARFARE CENTER WEAPONS
DIVISION
RF Guidance & Analysis Branch
Address: Code 087
China Lake, CA 935556001
(619) 939-2845
Funding Agency: Office of Naval Research
PR Number: 00PR00371-00
Award Number: N0001400WR20050
Current End Date: 30-Sep-2000
Scientific Officer: John Zolper

Objective:
This work seeks means of providing high performance amplifiers at
40 GHz and below with acceptable 1/f noise figures to be used in
missile tracking and intercept E/M systems. Specific objectives include
an output power of 1.5 watts at 30% duty cycle, 200 nanosecond pulse
width, and 24 db gain with 30% power added efficiency. The effort is
divided between industry and in-house.
Approach:
GaAlAs:GaAs heterojunction bipolar transistors will be designed and
tested. Performance will be optimized by achieving higher gain via a
better tradeoff between collector transit time and breakdown voltage and
by reducing parasitic capacitance between collector and base regions.
Further improvement will be achieved by better thermal design.
Contract effort is focused on device topological configuration
improvements to reduce parasitics and the use of InP/InGaAs to achieve
power and low noise in a single material and device type. In-house the
approach has been to develop extensive testing and evaluation of the
HBT technology that is being developed. Test capabilities include linear
and non-linear network analysis, on-wafer characterization and passive
load-pull system.
Progress:
During this period collector under cut AlGaAs/GaAs HBTs were modelled and tested. Modelling shows the expected improvement in the maximum frequency of oscillation, however; this was not seen experimentally in the large signal power or gain. The speculation was that the lack of experimental improvement was due to reduced thermal properties of the under cut HBT. Work was also initiated on an InGaP collector HBT that should offer superior performance over the AlGaAs/GaAs device due to better breakdown and surface properties.

Title: Frequency Converters
PI: Dean Nathans
SPACE AND NAVAL WARFARE SYSTEMS CENTER
SAN DIEGO
NCCOSC RDTE DIV
Address: Naval Command, Control & Ocean
Surveillance Center
San Diego, ca 921525001
(619) 553-1283
Funding Agency: Office of Naval Research
PR Number: 00PR00372-01
Award Number: N0001400WX20045
Current End Date: 30-Sep-2000
Scientific Officer: John Zolper

Objective:
To develop integrated circuits implementing L-band and higher
microwave band functions for high rate communications, sensor and
information systems. A reduced size(MMIC) synthesizer with low phase
noise is desired for use in UAVs. The synthesizer should provide for the
possibility of incorporation of frequency hopping capability. Also desired is a miniaturized RF translater that through monolithic
integration(bandpass filters, RF preamp, mixer, l.O., IF filter/amp)
would produce a common module that could be used in multiple
receiver spread spectrum TDMA systems such as JTIDS and MIDS.
Approach:
The frequency synthesizer exploits GaAs X-band HBT MMIC technology together with a commercially available phase detector IC. The RF translater is also expected to exploit MMIC technology.
Progress:
The contract to Hittite is continuing with a modified design to reduce
the fabrication cost of the monolithic RF translator. Cost sharing from
the MIDS program office was negotiated and the funding level from ONR
was adjusted to move the program forward.

Title: MICROWAVE TUNABLE ACTIVE FILTERS
PI: Christen RAUSCHER
NAVAL RESEARCH LABORATORY
CODE 6851
Address: NAVAL RESEARCH LABORATORY
WASHINGTON, dc 203755347
(202) 767-3526
Funding Agency: Office of Naval Research
PR Number: 00PR00373-00
Award Number: N0001400WR20016
Current End Date: 30-Sep-2000
Scientific Officer: John Zolper

Objective:
Develop techniques to realize compact, highly-selective tunable
microwave filters for use in high-dynamic-range, multifunction
transmit-receive and receive-only modules.
Approach:
Will focus on two main tasks: 1) the derivation and experimental
demonstration of improved circuit architectures and 2) the development
and demonstration of an improved semiconductor varactor technology.
Progress:
Work has concentrated on demonstrating a new low-loss heterostructure
varactor for use in a tunable notch filter, and on developing a suitable
test bed for verifying device performance. After extensive computer
simulations, heterostructure material was grown to specification by
MBE, comprising 15 layers of 50 Angstrom thick Si-doped GaAs interleaved with 1000 Angstom thick layers of undoped AlGaAs. The test-bed circuit encompasses two frequency-tunable bandpass filters separated by an MMIC amplifier, and is designed to maintain constant instantaneous bandwidth across the tuning range. Varactors and test filter are in the final stages of fabrication and assembly, respectively. Work has focused on the realization of heterostructure varactor diodes for use in a tunable notch filter, and on the development of a suitable test-bed circuit for verifying device performance. Two diode fabrication runs were completed, employing layered GaAs-AlGaAs material grown previously by MBE. A tunable active bandpass filter, to serve as test bed, was successfully implemented in hybrid-integrated-circuit form. The circuit was tested, using conventional GaAs varactor diodes. As predicted, the response maintained a constant absolute passband width across the specified 6-7 GHz tuning range.

Title: ULTRA HIGH SPEED InP BASED E/D HEMT ANALOG
TO DIGITAL CONVERTERS
PI: Ilesanmi Adesida
THE BOARD OF TRUSTEES OF THE UNIVERSITY
OF ILLINOIS AT URBANA CHAMPAIGN
DEPARTMENT OF ELECTRICAL & COMPUTER
ENGR.
Address: 208 N. WRIGHT STREET
URBANA, il 61801
(217) 244-6379
Funding Agency: Office of Naval Research
PR Number: 00PR00374-00
Award Number: N000149810376
Current End Date: 28-Feb-2001
Scientific Officer: John Zolper

Objective:
To demonstrate A/D converters with state-of-the-art InP based high
electron mobility transistors.
Approach:
InP based enhancement and depletion mode HEMTs will be
fabricated using selective recess etching to achieve high performance
and high yield A/D circuits.
Progress:
Work has focused on improving the performance of enhancement-mode
InAlAs/InGaAs/InP HEMTs. Whereas previous work on HEMTs utilized
heterostructures with electron sheet density of 0.7E+12 cm-3, new
layers have a sheet density of 1.0E+12 cm-3. The aim is to enhance the
unity current-gain cut-off frequency to well over 100 GHz. A novel
Pt/Mo gate metallization is being developed for the E-mode HEMTs in
order to ensure a reliable self-limiting Pt reaction with InAlAs for a more uniform threshold voltage. This will also allow a single-step annealing process for the gate and ohmic metallizations. Work has commenced on developing realistic circuit models for HEMTs. Simple circuits have been designed and laid out consisting of differential pairs of E/D HEMTs in order to determine device matching characteristics.

Title: Wide Bandgap Broad Bandwidth HBT Amplifiers
PI: William Schaff
CORNELL UNIVERSITY
Department of Electrical Engineering
Address: 415 Phillips Hall
Ithaca, NY 14853
(607) 255-3974
Funding Agency: Office of Naval Research
PR Number: 00PR00375-00
Award Number: N000149810015
Current End Date: 14-Oct-2000
Scientific Officer: John Zolper

Objective:
To develop and demonstrate heterostructure bipolar transistor (HBT)
amplifiers with required bandwidth, linearity, and efficiency. The
dominant element in development of these amplifiers will be the
capabilities of the HBT. This program will develop a GaN-emitter
SiC-base-collector HBT suitable for meeting high performance amplifier
requirements. While the high temperature capability of wide bandgap
transistors required for high power operation is known, HBT device
parasitics need to be minimized for amplifier applications.
Approach:
Both materials growth and device process developments will be
undertaken to develop a high performance GaN/SiC HBT. Starting with
commercially available SiC epitaxial layers of the the collector and
subcollector, additional SiC and/or GaN layers will be grown by either
chemical vapor deposition or molecular beam epitaxy. High level p-type
doping of SiC, as required for the HBT base, will be developed via either epitaxial growth or ion implantation. Flip chip bonding will be applied to the HBT to optimize heat removal from devices during high power operation to enhance circuit efficiencies. Class B power amplifier will be developed based on the proposed HBT. The amplifiers will be designed to minimize backward wave propogation on the trans-mission line. This will involve new circuit design approaches.
Progress:
Modelling was performed of WBG HBT DC characteristics. Developed alternative HBT designs to include piezoelectric effects. Developed single step techniques for epitaxial growth of GaN on SiC for
formation of GaN emitters on a SiC base and collector. Began fabrication of Base-Collector diodes to characterize deep levels in p-SiC which might limit electron lifetimes and HBT gain. Began design of HBT process including: layout of e-beam lithography masking for cascade probe RF HBT transistors and characterization of dry etching. The project remains on schedule. Established spontaneous and piezoelectric effects in AlGaN/SiC base-emitter junction designs. Began process development to address the polarization effects -patterned base mesas to extend nitride critical thickness AlGaN emitters to raise valence band offset for 4H SiC heterostructures. Began evaluation of nitride/carbide inter-face intermixing. Conceived a wafer bonding process to mate N-face GaN with Si-face SiC.
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posted 06-07-2002 02:21 PM            

Title: Multifunction Wideband, High Resolution, 1
GHz Analog-Digital Converter (ADC)
PI: William Skones
TRW INCORPORATED SPACE AND TECHNOLOGY
DIVISION
Electronic Systems Group; M/S M5/1454
Address: One Space Park
Redondo Beach, CA 90278
(310) 813-2420
Funding Agency: Office of Naval Research
PR Number: 00PR00442-02
Award Number: N000149920004
Current End Date: 30-Mar-2002
Scientific Officer: Deborah Van Vechten

Objective:
Develop a hybrid ADC consisting of a new 3 bit sigma delta ADC
composed of high fT InP HBTs with the loop residual sampled by a 9
GaAs Nyquist Subranging ADC developed under other government contracts. This ADC is expected to meet the performance specifications expressed in the AMRFS BAA ONR 98-022 and so enable the concept of reconfigurable, multi-function receive apertures.
Approach:
Use a hybrid architecture to achieve the high SINAD of sigma delta
ADCs and the high SFDR of a Nyquist ADC without going to the very
high sample rate required in a pure sigma delta design. Utilize both the
current state of the art Ft>100 GHz InGaAs/InAlAs/InP IC technology
and the >200 GHz improvement currently under ONR funded
development. Correct the DAC errors outside the loop and work hard to
improve the loop filter performance. FPGA will be used in the back end
combining logic to prove the design before custom ASIC production.
Progress:
The initial iteration of design work has nearly completed the detailed
circuit designs. HBT device improvement continues with toggle flip flops executing at above 65 GHz.

Title: A Study of the Switching Speed of
Magnetoquenched Superconductive Devices &
their Applicability to Practical
Superconductive Electronics
PI: Steven Kaplan
HYPRES INC
Address: 175 Clearbrook Rd
Elmsford, NY 10523
(914) 592-1190
Funding Agency: Office of Naval Research
PR Number: 00PR00444-00
Award Number: N0001499C0128
Current End Date: 31-Dec-2001
Scientific Officer: Deborah Van Vechten

Objective:
Mesoscopic Magnetoquenched Superconducting Valves (MMSV) were demonstrated using lead for the superconductor in fy98 at NRL under
ONR support. These devices are a leading possibility for on-chip
memories for use with niobium (Nb) based digital circuits operating in
100 GHz SFQ logic systems at 4 K. The objective of this effort is define
more clearly the set of requirements for such memory and help evaluate
the MMSV and other magnetic concepts. The devices are needed for the proposed petaflop computer to provide low power, fast cache memory
close to the central processors, a function currently without good
candidate devices. They also could be used in high fidelity DRFM
applications and in the beam/function control portions of the AMRFS
system.
Approach:
The approach is to work with Dr. Johnson of NRL and Prof. Beasley at
Stanford to jointly test the viability of alternative magnetic memory
devices for 4K digital systems. HYPRES will facilitate fabrication of
niobium MMSV devices by providing wafers with Nb films on ground planes to NRL as needed and collaboratively design masks for high speed tests of the basic devices, to be done at HYPRES. Dr Kaplan will help Dr Beasley define the requirements of a memory device used by and near a high speed (100 GHz) SFQ superconducting circuit. Suitable probes will also be designed (8 high speed and multiple low speed lines) and purchased for use in testing at both NRL and HYPRES.
Progress:
Designs have been iterated and are ready for fabrication. New probe is
on order.

Title: Low-Loss High Speed Tunable Filters
PI: Salvador Talisa
NORTHROP GRUMMAN CORPORATION
Address: PO Box 746 MS 1110
Baltimore, MD 21203
(410) 993-2910
Funding Agency: Office of Naval Research
PR Number: 00PR00445-00
Award Number: N0001499C0157
Current End Date: 30-May-2001
Scientific Officer: Deborah Van Vechten

Objective:
To demonstrate room temperature pass band filters that can be switched
as to center frequency by a set of MEMS actuated capacitors in
combination with printed inductors. Units with 16 center frequencies in
the 1-5 GHz band will be demonstrated, but preliminary designs for the
4-20 band will also be produced. Critical parameters include insertion
loss <0.5 dB so that they can be used before the LNA in receivers, TOI
>60 dB because there will be multiple signals received by every element,
and switching times less than 1 microsecond. Low cost and MMIC
compatibility are also requirements. These filters are needed to achieve
adequate isolation in the AMRFS multiple simultaneous function
context.
Approach:
The MEMS switches and filter designs have already demonstrated sufficient Q, TOI, power handling, and low insertion loss and LTCC is an
appropriate packaging material. Similar switches have shown no failure
after the equivalent of 10 yrs of switching every 200 microsec. What is
most required is to decrease the MEMS switching time from a few
microsec to less than 1 by modifying the geometrical design of the fixed
electrode and its interaction with the moving electrode and shaping the
control pulse. Measurements will be made of the noise added by these
passive devices, but is expected to be low.
Progress:
This effort will combine MEMS, fixed lumped-element filters and
low-temperature cofired ceramic (LTCC) packaging. The initial work will
demonstrate switchable tuning of high Q filters using MEMS and
proprietary miniature (lumped) inductors.

Title: DENSELY PACKED ARRAYS FOR ANTI-JAM GPS
PI: Donald Bowling
NAVAL AIR WARFARE CENTER WEAPONS
DIVISION
Weapons Division
Address: China Lake, CA 935556001
(760) 939-3089
Funding Agency: Office of Naval Research
PR Number: 00PR00446-01
Award Number: N0001400WX20392
Current End Date: 30-Sep-2000
Scientific Officer: Deborah Van Vechten

Objective:
GPS receivers are one of the important applications where typical units
lack sufficient size to deploy conventional halfwave length antennas due
to the relatively large wavelength of the frequency used. This effort seeks to develop densely packed arrays of electrically small elements capable of active null steering to provide maximal protection against jamming.
Approach:
The effort will focus on alternative designs for densely packed arrays of electrically small elements that would fit within the 4 inch footprint of already deployed F-18 units. A capability to switch from
omni-directional sensitivity to a mode where pattern nulls are
dynamically pointed at jammers will be designed in. Selected designs
will be simulated using IE3D and Aerospace Corp. adaptive beam
steering capabilities program. The best design will then be fabricated in both normal metal and high temperature superconductors. Testing in
TEM cell will determine both whether the design functions as expected
and how much of a performance advantage the HTS version offers. A
digitally beam-formed densely packed array will be demonstrated, with
integrated cryocooler if HTS, by the end of the program.
Progress:
Sequential scanning of linear arrays is the basic element in the
production of virtual doppler effects. Issues of mutual coupling of
elements and the effect of various smoothing functions on the power
spectral density were studied. Hardware construction is complete and
tests begun to confirm the simulations using a 12 element array.

Title: 100 nm Fabrication Science and TFSOS/SOI
Device R&D
PI: Isaac Lagnado
SPACE AND NAVAL WARFARE SYSTEMS CENTER
SAN DIEGO
Center RDT&E Division (NRaD)
Address: SAN DIEGO, CA 921525000
(619) 553-2682
Funding Agency: Office of Naval Research
PR Number: 00PR00447-00
Award Number: N0001400WX20105
Current End Date: 30-Sep-2000
Scientific Officer: Ingham Mack

Objective:
Develop an advanced high speed, low power, and high density integrated circuit technology with feature sizes that are readily down-scalable to the 0.18-0.10 micron regime based on the use of ultra-thin, fully depleted silicon films on sapphire. This inherently radiation tolerant technology will be used to enhance reliability, cost effectiveness, and performance of current and future Navy systems.
Approach:
Techniques to realize CMOS devices with channel lengths <0.25um
will be developed using fully depleted thin-film silicon-on-sapphire (TFSOS) technology. Use of Si/Ge and operation at cryoelectronic
temperatures (77K) will be investigated to enhance device performance.
TFSOS technology will be the basis for implementing A/D converters,
artificial neural networks, and UHF/L band transceivers for
communications applications.

Title: High Power Electronics Building Block
(PEBB) - Programmable High Density PEBB
Power Supply
PI: Isaac Lagnado
SPACE AND NAVAL WARFARE SYSTEMS CENTER
SAN DIEGO
Center RDT&E Division (NRaD)
Address: SAN DIEGO, CA 921525000
(619) 553-2682
Funding Agency: Office of Naval Research
PR Number: 00PR00448-00
Award Number: N0001400WR20049
Current End Date: 30-Sep-2000
Scientific Officer: Ingham Mack

Objective:
Develop technology for providing the manufacturing and commercialization base for a power supply technology for the Power Electronic Building Block (PEBB) with high power density (>150-200 watts per cubic inch), low profile (<0.2 in) and programmable multiple low voltage outputs that are immune to the harsh EMI environment expected from the PEBB.
Approach:
Techniques to realize high efficiency, high power density, low output
power will be developed by use of a soft switched power converter
topology. Techniques for the power supply to operate in a high EMI
environment will be developed by use of electrostatic shielded matrix
magnetics. A low volume, low profile supply will be developed through
use of a high operating frequency (>2 MHz) for passive component size
reduction and chip-on-board packaging. This program will be partially
funded by the Electronics Program and partly by the PEBB Program.

Title: Workshop on Doping, Dopants and Low Field
Carrier Dynamics in Wide Gap Semiconductors
PI: Alexander Scott
TMS
Structural Materials Division
Address: 420 Commonwealth Drive
Warrendale, PA 150867514
(724) 776-9000
Funding Agency: Office of Naval Research
PR Number: 00PR00449-00
Award Number: N000149910766
Current End Date: 30-Jun-2000
Scientific Officer: Colin Wood

Objective:
To address transport problems in wide gap semiconductors.
Approach:
By assembling experts in the field it is expected that possible solutions will be rapidly identified.

Title: Electron Emission from cBN & Related Wide
Bandgap Systems
PI: Roy Clarke
THE REGENTS OF THE UNIVERSITY OF
MICHIGAN
Applied Physics Program
Address: H. M. Randall Laboratory of Physics
Ann Arbor, MI 481091120
(734) 764-4466
Funding Agency: Office of Naval Research
PR Number: 00PR00450-01
Award Number: N000149910337
Current End Date: 31-Dec-2002
Scientific Officer: Colin Wood

Objective:
Seeks to better understand the crystalline defects in cubic boron nitride so as to better exploit this new material system for enhanced
electromagnetic system applications.
Approach:
Cubic boron nitride films will be synthesized on lithographically
defined field tip arrays on single crystalline silicon at the University of Michigan. These films will then be analyzed by x-ray scattering,
cathodoluminescnce, RHEED and related tools to determine the nature
of defects in the material.
Progress:
The first task of the project, testing of the UHV cold-cathode emission
station, has been accomplished according to the proposal timetable. The
second task, to characterize emission from silicon field emitter arrays in collaboration with Pang's group, is also successfully accomplished
within the proposal timeline. The third task, to coat these arrays with
cubic boron nitride for improved emission characteristics, is underway.
Being explored is self-assembled nano-tip arrays as a cheaper and more
convenient alternative to conventional lithography. We have formed a
collaboration with Dr. Kevin Jensen (NRL) and Jim Severns (Praxis) to
transfer some of the UM's coated nano-tip technology to their field
emitter array program for space applications. One student supported by
the grant has graduated with a Ph.D. during this reporting period and
has taken a position as Staff Scientist with Seagate Technology.

Title: A STUDY OF GROWTH MORPHOLOGY AND DEFECT
GENERATION IN ALUMINUM NITRIDE CRYSTALS
GROWN BY SUBLIMATION
PI: James Edgar
KANSAS STATE UNIVERSITY
Department of Chemical Engineering
Address: Durland Hall
Manhattan, KS 665065102
(785) 532-5584
Funding Agency: Office of Naval Research
PR Number: 00PR00452-00
Award Number: N000149910104
Current End Date: 30-Nov-2001
Scientific Officer: Colin Wood

Objective:
To investigate unique and efficacious means of preparing semiconductor grade aluminum nitride single crystals.
Approach:
Crystals to be grown by sublimation under reduced nitrogen atmospheric pressure at temperatures in excess of 2250C.
Progress:
Thick films of AlN have been grown as a first step to bulk crystal
growth. Future research is aimed at improving lifetime of equipment
against degradation by aluminum at high temperatures. Once this is
solved there are no forseen obstacles to growth of commercial scale AlN
semiconductor substrates.

Title: Novel Deposition and Characterization of
Cubic Boron Nitride Films by MOCVD Method
PI: Gary Harris
HOWARD UNIVERSITY
Office of Research Administration
Address: 2400 Sixth St., NW
Washington, DC 20059
(202) 806-6595
Funding Agency: Office of Naval Research
PR Number: 00PR00454-01
Award Number: N000149710935
Current End Date: 31-Jul-2000
Scientific Officer: Colin Wood

Objective:
To prepare single crystal semiconducting (cubic lattice) boron nitride
(BN) for use in ultra-violet countermeasures.
Approach:
Metal organic vapor phase depostion (MOCVD) will be used to
epitaxially grow epitaxial films on thin buffer layers with close lattice match, such as AlN, or AlP.
Progress:
The epitaxial growth of boron nitride and aluminum boron nitrides
have been carried out employing low-pressure chemical vapor deposition
methods. Both (0001)sapphire and (100) silicon have been used as
substrates. Atomic force microscopy, Auger electron spectroscopy, Hall
mobility measurement and X-ray diffraction studies have been
performed to characterize the layers. AES data confirm the deposition of both AlN and BN layers on Si with roughness less than 10 nm. The
layers are currently polycrystalline. Currently growth conditions are
being optimized to improve the crystalline quality desirably to cubic
structure.

Title: DEVICE PROPERTIES OF SiGeC ALLOYS AND
HETEROJUNCTIONS
PI: James Kolodzey
UNIVERSITY OF DELAWARE
Department of Electrical Engineering
Address: 77-79 East Delaware Avenue
Newark, DE 19716
(302) 831-1154
Funding Agency: Office of Naval Research
PR Number: 00PR00456-00
Award Number: N000149310393
Current End Date: 28-Feb-2000
Scientific Officer: Colin Wood

Objective:
To experimentally determine the physical and electronic properties
of Si(1-x-y)Ge(x)C(y) and how they vary with compositional parameters;
understand the results in terms of conventional semiconductor energy band theory; and assess the suitability of the material for electronic and optoelectronic device appplications.
Approach:
Layers of Si(1-x-y)Ge(x)C(y) will be grown using PECVD and MBE.
Their properties will be characterized using physical, electrical, and
optical measurements. Heterojunctions and heterojunction device
structures will be fabricated and characterized.
Progress:
It was found that the optimum substrate temperature for good surface morphology was 600 C for SiGeC alloys, and 450 C for GeC alloys. The optical absorption coefficients of SiGeC and SiGeCSn alloys were determined using FTIR. It was found that the absorption edge near
the bandgap energy varied with composition, but not linearly. It appears that the addition of C increases the bandgap energy for Ge-rich alloys - but this finding is controversial because other groups (Princeton, ASU) claim C decreases the bandgap, therefore; this result is being checked. The discrepancy may be that samples used in the present work are thick and relatively strain-free whereas groups claiming C decreases bandgap reported on thin strained layers. A SiGeC/Si p-n heterojunction diode was fabricated with nearly ideal current-voltage characteristics, and significant photoresponse. The hole mobility in SiGeC and GeC was found to be higher than in pure Si by a factor of three.

Title: INVESTIGATION ON NITRIDE SEMICONDUCTORS ON
ZnO SUBSTRATES AND ZnO HETEROSTRUCTURES
PI: Hadis Morkoc
VIRGINIA COMMONWEALTH UNIVERSITY
Dept. of Electrical Engineering &
Physics
Address: 601 West Main Street
Richmond, VA 23284
(217) 333-0722
Funding Agency: Office of Naval Research
PR Number: 00PR00457-00
Award Number: N000149810139
Current End Date: 30-Nov-2000
Scientific Officer: Colin Wood


Objective:
To improve epitaxial nitride semiconductor films to be suitable for
exploitation as high power microwave devices for military systems.
Approach:
Zinc oxide substrates will be used instead of the less well lattice
matched sapphire or SiC.
Progress:
Inversion domain free GaN may be grown on ZnO which decomposes at
high temperatures and under ammonia, necessitating a low temperature GaN buffer layer grown with RF activated N source. A new MBE system has been installed; characterized GaN films on inexpensive Si substrates are studied; installed an EPI RF source; obtained ZnO substrates from Cermet, albeit a-plane, and are acquiring c-plane substrates from Air Force Research Laboratories. Soon, we will be well positioned to begin growing GaN films on ZnO substrates.

Title: ADVANCED MATERIAL INTEGRATION FOR Sb-BASED
BIPOLAR TRANSISTORS
PI: Karl Hobart
NAVAL RESEARCH LABORATORY
ES&T Division
Address: ES&T Division
Washington, DC 203755347
(202) 404-8542
Funding Agency: Office of Naval Research
PR Number: 00PR00458-00
Award Number: N0001400WR20048
Current End Date: 30-Sep-2000
Scientific Officer: Colin Wood

Objective:
Endeaver to wafer bond antimonide semiconductor films and ICs to SiC
polycrystaline silicon carbide substrates.This will allow low parasitic,
high thermally stable electronics for true time delay microwave radar
systems.
Approach:
Will use Vander Waals forces between extremely flat and polished
surfaces at moderate temperature. Under vacuum conditions, and with
correct chemical surface treatment most materials will bond very strongly to each other. Using undercutting of base films it is expected
that semiconductor structures for ultra fast devices and circuits will
develop in this program.
Progress:
A new source of high resistivity (>10^5 ohm-cm)100mm diameter poly-crystalline SiC has been determined and substrates have been procured; these poly-SiC substrates have been successfully polished to <0.2 nm rms roughness for bonding; the Smart-Cut process for GaSb has been optimized for cleaving temperature and damage reduction; GaSb substrates coated with APCVD SiO2 are presently being polished by CMP to prepare for bonding.

Title: Direct Digital SynthesizerULTRA HIGH
SPEED DDS FOR ELECTRONIC BEAM STEERING
PI: Augusto Gutierrez
TRW INCORPORATED SPACE AND TECHNOLOGY
DIVISION
Electronic Systems & Technology

Funding Agency: Office of Naval Research
PR Number: 00PR00471-01
Award Number: N0001498C0111
Current End Date: 08-Jul-2001
Scientific Officer: Max Yoder

Objective:
This work seeks the direct digital synthesis and modulation of RF
signals to 18GHz.
Approach:
Low parasitic heterojunction bipolar transistors will be exploited to
develop logic capable of operating from a 100 GHz low phase noise clock.
Progress:
Excellent progress has been made in InP DHBT technology during this
year. A viable production solid source phosphorus technology was
developed as it was necessary to achieve maximum analog performance
with ultra high frequency. Excellent InP DHBT devices with > 800v
Early voltage were developed as necessary for precision DAC current
sources. The contractor also developed an initial undercut collector
etching capability using the anisotropic etching characteristics of InP
which will allow them to achieve minimum collector-base capacitance
while simultaneously providing low base resistance. This approach will
provide the device performance for a producible high analog LSI yield
THz HBT for the 100 GHz DDS. Progress has been made on undercut
InP DHBT technology. The recent lots have demonstrated greater
current handling and high ft, and fmax > 190 GHz. The undercut
devices have yielded the world's fastest digital circuit, a static frequency divide by 2 prescaler operating to > 63 GHz. This was achieved while dissipating only 63 mW of power in the core divider circuit. Although this was the first design with preliminary models, the divider design simulation matched the measured circuit performance to within 10%. Based on these results DDS architecture design has begun and the continuation of improvement on MBE profile and process to improve ft, and fmax.

Title: Analog to Digital Conversion
PI: Isaac Lagnado
SPACE AND NAVAL WARFARE SYSTEMS CENTER
SAN DIEGO
Center RDT&E Division (NRaD)
Address: SAN DIEGO, CA 921525000
(619) 553-2682
Funding Agency: Office of Naval Research
PR Number: 00PR00477-01
Award Number: N0001400WX20104
Current End Date: 30-Sep-2000
Scientific Officer: Ingham Mack

Objective:
Develop technology for providing high performance, low power,
radiation tolerant analog-to-digital converters that can be used in Navy
surveillance, EW, and communications systems applications.
Approach:
Analog-to-digital converters using CMOS fully depleted thin-film
silicon-on-sapphire technology with feature sizes <0.25um will be
utilized to implement A/Ds with sigma-delta as well as flash architectures. Current emphasis is on the development of a 16 bit, 125
MSPS ADC using the sigma-delta approach for applications to ASW. A
4-bit, 20 GSPS ADC using T-gate and SiGe devices will serve as the
quantizer for a 10-bit, two-step flash, 2.5 GSPS ADC for surveillance and EW applications. Development of an 18 bit, 100 KSPS, 1 mW ADC will
be pursued to meet the demands of on-site signal processing in
unattended, remotely controlled systems.

Title: Resonant Quantum Excitation in HTS: A
Probe of the Striped Phase and Its
Influence on Microwave Properties
PI: T. Venkatesan
UNIVERSITY OF MARYLAND AT COLLEGE PARK
Department of Physics
Address: College Park, MD 20742
(301) 405-7320
Funding Agency: Office of Naval Research
PR Number: 00PR00478-00
Award Number: N000140010028
Current End Date: 31-Dec-2002
Scientific Officer: Deborah Van Vechten

Objective:
To determine if phase segregation of electrons in high temperature
superconductors into dynamically fluctuating antiferromagnetic and
superconducting regions is the source of the observed resonant pair
breaking effect and of the nonlinearities which result in inter-modulation distortion in HTS filters. If so, the optical measurements can be used to create overwhelmingly superior materials (IP3>100 dB) for use in Navy multifunction rf systems such as AMRFS.
Approach:
Fabricate thin film samples of materials expected to have wide range of
behavior of stripes (parent antiferromagnets, plane vs chain doped
YBCO, 214 LSCO with stripes stabilized by Nb doping and under varied
stress due to substrates). Measure optical response and correlate to
microwave loss measurements of Sridhar, IP3 measurements at NIST, and previous studies of psuedogap. Use silver doped YBCO to test Mannhart's assertion that antiferromagnetic regions exist in grain boundaries by reducing the number of grain boundaries. The PI will produce the samples needed for his own and collaborators efforts.

Title: Theory of Transport Processes in Nitride
Structures
PI: Brian Ridley
UNIVERSITY OF ESSEX
Department of Physics
Address: Wivenhoe Park
Colchester, VA 222175660
(607) 256-4369
Funding Agency: Office of Naval Research
PR Number: 00PR00479-00
Award Number: N000149910014
Current End Date: 30-Sep-2000
Scientific Officer: Colin Wood

Objective:
PI will calculate and model electrical carrier transport at low and
high electric fields in wide bandgap compound semiconductors. He will provide insight to operation of devices under investigation by ONR
funded PIs.
Approach:
Calculational theory and code developed over the last two decades
will be used for theoretical modelling and prediction.
Progress:
A post.doc. RA, Dr. Ceyhun Butulay, joined Essex 1 January 1999. An exact solution of the Boltzmann equation for the low-field drift
mobility in GaN associated with polar-optical-phonon scattering was
obtained and published. Inclusion of electron-electron and acoustic-phonon scattering has now given us an upper limit to the bulk mobility. An extension to the 2D case has been made. A calculation of the low-field mobility in AlGaN will be presented at the Nitride Conference in Montpellier in July. Results of a study of piezoelectric scattering was presented at the Spring meeting of the MRS. The effect of Wannier-Stark quantization on the impact-ionization rate in bulk material has been published.

Title: Low Energy Electron Microscopy
Investigations of Fundamental Mechanisms in
Group III Nitride Growth
PI: Max Lagally
THE BOARD OF REGENTS OF THE UNIVERSITY
OF WISCONSIN
Materials Science and Engineering
Address: 750 University Avenue
Madison, WI 53706
(608) 263-2078
Funding Agency: Office of Naval Research
PR Number: 00PR00482-01
Award Number: N000149610323
Current End Date: 30-Sep-2002
Scientific Officer: Colin Wood

Objective:
To optimize the growth of GaN by application of Low Energy Electron
microscopy real time to the epitaxial growth surface. Si quantum dots
embedded in GaN films will be investigated for light emission and high
power microwave applications relevant to the US Navy.
Approach:
Low-energy electron microscopy (LEEM) will be used to investigate
the homoepitaxial growth of GaN on single crystal GaN substrates. The
morphological aspects of the growth front will be studied as a function of growth parameters such as nitrogen pressure, deposition rate,
temperature and substrate condition in order to determine quantitative
thermodynamic and kinetic mechanisms. A novel atomic nitrogen
source will be fabricated and installed in the LEEM. In this source a
CO2 laser fires into the throat of a nozzle creating a nitrogen plasma.
The plasma then expands and is neutralized by collisional recombination. Its composition is then frozen by the nozzle expansion.
Progress:
Low-energy electron microscopy (LEEM) has been used to investigate
the homoepitaxial growth of GaN on single crystal GaN substrates. The
morphological aspects of the growth front studied as a function of
growth parameters such as nitrogen pressure, deposition rate,
temperature and substrate condition have been used to determine
quantitative thermodynamic and kinetic mechanisms. A novel atomic
nitrogen source has been fabricated and installed in the LEEM.
Using the new LEEM GaN chamber the PI has observed facetted growth of
GaN on GaN/sapphire at low temperatures. PI has identified regions on
LEO GaN suitable (because they have large, step-free regions) for
investigating nucleation and initial growth. PI has tested the plasma
source using oxygen, and has found that a significant hyperthermal
component of O atoms is produced. PI has nearly completed the
STM/GaN growth chamber and will grow GaN on Si(111), for purposes of
integrating GaN/Si using multi-orientation SOI. PI has investigated
patterned Si(001) and SOI in the LEEM, and has achieved large (~15m)
step-free pedestals.

Title: INTERFACIAL BONDING RESEARCH FOR COMPLIANT
SUBSTRATES
PI: David Miller
THE PENNSYLVANIA STATE UNIVERSITY
Science Center
Address: 1049 Camino Dos Rios, P.O.Box 1085
Thousand Oaks, CA 91360
(805) 373-4275
Funding Agency: Office of Naval Research
PR Number: 00PR00484-00
Award Number: N000149710951
Current End Date: 30-Jun-2000
Scientific Officer: Colin Wood
Objective:
To determine parameters of preparation of bonded substrates for
molecular beam epitaxy of lattice mismatched electronic materials.
Approach:
Examine the effects of interfacial chemistry, gas, oxide and contami-nants, as well as surface finish and topography on the temperatures, conditions and results of bonded GaAs on Si.
Progress:
The PI has focused on two areas: relaxed epitaxial growth of InGaAs
on a twist-bonded GaAs compliant substrates and GaAs compliant
substrates bonded with intermediate SiO2 or indium oxide layers; and
relaxed epitaxial growth of InGaAs on a compliant substrate fabricated
by epitaxial growth of an AlAs/GaAs structure with the subsequent
oxidation of the AlAs. They have developed methods to improve the
cleanliness and smoothness of the surfaces of both types of compliant
substrates for subsequent epitaxial growth and have successfully
produced intact GaAs layers as thin as 30 nm on top of oxidized AlAs in
stripes 100 micron wide. They have successfully grown GaAs epitaxially
over these thin layers. So far, however, large areas of dislocation-free epitaxial material grown on these compliant substrates have not been achieved, in part because lattice-mismatched epitaxy still nucleates poorly on these surfaces.The postdoc previously supported by this program was hired by industry (QED, Inc., Bethlehem, PA) in February 1999 and a new postdoc with extensive material growth experience has been hired. Research focus has been shifted from thin GaAs on oxidized AlAs to twist-bonded materials and the use of bonded wafers using antimonide compliant layers. Careful characterization of InGaAs layers grown on thick GaAs substrates has been done as preparation for growth of InGaAs on these complaint substrates. Two papers were published last year reporting results from this project.

Title: USE OF PIEZOELECTRIC CHARGE IN HEMT'S ON
GaAs AND InP SUBSTRATES
PI: Lester Eastman
CORNELL UNIVERSITY
School of Electrical Engineering
Address: 120 Day Hall
Ithaca, NY 14853
(607) 255-4369
Funding Agency: Office of Naval Research
PR Number: 00PR00485-00
Award Number: N000149810161
Current End Date: 31-Dec-2000
Scientific Officer: Colin Wood

Objective:
To fabricate and investigate improvements of Field effect transistor
operation and performance using piezo-electric fields in the C-direction of the crystals and thus avoid the need for dopant incorporation and control during epitaxial film growth.
Approach:
The PI will determine the magnitude of the Piezo electronic co-efficients in GaAs/AlInGaAs heterostructures in the (111) direction. Once determined FET devices will be designed, built and characterized, and the performance advantages evaluated.
Progress:
Initial experiments on oriented GaInAs on GaAs substrates have
demonstrated the extent of Piezo-electric effect. Calculations are
underway to determine the extent of spontaneous polarization to distinguish it from strain induced polarization effects. Attempts to
achieve piezoelectrically-induced holes with (III)B GaAs substrates have
been tried without success. The expected hole sheet density is well
below 1 x 1012/cm2 and is masked by background donors in the buffer
layer. The use of (III)B InP, to induce a 2DEG, where the density is
expected to be 2-3 x 1012/cm2, is being studied. Lattice matched
InGaAs and InAlAs have been achieved and growths of lattice-matched
InGaAs covered with strained In1-yAlyAs will be made. Using a thin barrier of the latter, at the critical layer thickness, the 2 DEG
density will be determined.

Title: P-Type Doping in GaN
PI: Fred Schubert
THE TRUSTEES OF BOSTON UNIVERSITY
College of Engineering
Address: 44 Cummington Street
Boston, MA 022152407
(617) 353-1910
Funding Agency: Office of Naval Research
PR Number: 00PR00486-00
Award Number: N000149810194
Current End Date: 30-Nov-2000
Scientific Officer: Colin Wood

Objective:
To produce higher hole concentrations in GaN for much reduced resistance contacts, and lower parasitic series resistance in AMRFS related devices.
Approach:
PI will prepare oscilliatory compositional superlattices of Mg
saturated GaN /InN films by molecular beam epitaxy. This will change
the band structure thereby reducing the effective mass and thence the
activation energy, and allowing low resistance contacts for AMRFS
related devices.
Progress:
Instabilities in Hall measurements from samples of GaN grown on
Sapphire have been discovered. A time dependant scan technique that
leads to 3 orders of magnitude increased accuracy has been developed.
Also discovered is that when using ethylene glycol as a solvent peroxide
can be used and etchant such as phosphoric acid to define facets on c
plane GaN on Sapphire. Mg-doped AlGaN/GaN superlattices are investigated in order to enhance the doping properties of GaN which suffers from low carrier activation due to an acceptor activation energy of 200 meV. Demonstrated that the activation energy of acceptors is reduced to 70 meV and 58 meV in AlGaN/GaN superlattices with 10% and 20% Al content, respectively. The free hole concentration of the superlattice with 20% Al content is 8 x 10^18 cm^-3 at 400 K. The doping properties improve with increasing Al content of the superlattices, in agreement with theoretical model.

Title: Supplimental funding for N0001496-1-1008
PI: Thomas Myers
WEST VIRGINIA UNIVERSITY RESEARCH
CORPORATION ON BEHALF OF WEST VIRGINIA
UNIVERSITY
Department of Physics
Address: P.O. Box 6315
Morgantown, WV 265066315
(304) 293-3422
Funding Agency: Office of Naval Research
PR Number: 00PR00488-02
Award Number: N000149611008
Current End Date: 30-Sep-2002
Scientific Officer: Colin Wood
Objective:
This program seeks to determine and exploit the mechanism whereby
hydrogen atoms enhance the stability of group III nitride thin films in
vacuum, which enhances apparent growth rate during molecular beam
epitaxy.
Approach:
Reflection electron diffraction and molecular desorption spectroscopy
will be used as real-time probes of the surface stoichiometry, crysta-linity, and smoothness during thin film growth of the group III nitrides. MBE with elemental group III and nitrogen plasma sources will
be employed.
Progress:
Atomic hydrogen stabilizes the growing GaN surface during molecular
beam epitaxy (MBE), allowing higher temperatures necessary for high
quality material. Study of defects affecting surface morphology suggest
the majority of MBE growth results in a crystal polarity which enhances
defect formation, indicating that growth initiation must be changed.
The PI will continue to investigate growth kinetics of GaN, InN and
InGaN (including the effect of atomic hydrogen) to understand growth
processes and allow alloy growth at GaN-compatible temperatures.

Title: GROWTH AND FABRICATION OF GaN-BASED
HETEROJUNCTION BIPOLAR TRANSISTORS
PI: April Brown
GEORGIA TECH APPLIED RESEARCH
CORPORATION GEORGIA INSTITUTE OF
TECHNOLOGY
School of Electrical and Computer
Engineering
Address: 212 Pettite Building
Atlanta, GA 303320250
(404) 894-5161
Funding Agency: Office of Naval Research
PR Number: 00PR00489-00
Award Number: N000149810209
Current End Date: 31-Dec-2000
Scientific Officer: Colin Wood
Objective:
To develop heterojunction bipolar transistors for high power
microwave operation without active cooling.
Approach:
This program will utilize and exploit piezo-electric fields within
heterojunction nitride semiconductor based bipolar transistor multilayer
structures. These will be grown at GA Tech by MBE, and processed at U
Illinois.
Progress:
This project has demonstrated: 1.) the first growth of a device
quality nitride structure on lithium gallate, a low cost alternative
substrate 2.) the elimination of the low temperature buffer normally
required to nucleate the nitride films on heterogeneous substrates (this buffer is a source of defects that limits the device performance), 3.)
the lowering of dislocation densities to the low 1e8 per cm2 range
without the need for expensive multistep processes such as Lateral
Epitaxial Overgrowth, and 4.) much improved AlGaN material quality (a
critical part of the heterostructure) as evidenced by a 50% narrower
X-ray diffraction width as compared to material grown on sapphire,
HVPE GaN and silicon carbide. Have recently replaced Oxford rf
plasma source with an EPI plasma source (July 99) and have realized
increased growth rates (x3) and preliminary indications of increased
p-type doping efficiency and control on sapphire and LGO substrates.
Have designed heterostructures for achieving polarization (sponta-neous and piezoelectric) enhancements on cation- and anion-terminated growth faces. The achievement of a reproducible p-type doping is necessary to realize such enhancement. Theoretical studies of GaN/AlGaN HBT structures indicate that in the absence of piezoelectric effects and using a best estimate of the mobility and a free hole concentration of 1 cm2/V-s and 5.0 E18 respectively that the maximum value of fmax is about 3.5 GHz for a 0.075 micron wide base. Have also found that grading the heterojunction as opposed to using an abrupt heterojunction results in a 20% improvement in the integrated hole density when piezoelectric field effects are included.

Title: Glasses and Fibers
PI: Ishwar Aggarwal
NAVAL RESEARCH LABORATORY
Code 5603
Address: 4555 Overlook Avenue
Washington, DC 20375
(202) 767-9316
Funding Agency: Office of Naval Research
PR Number: 00PR00495-01
Award Number: N0001400WX20494
Current End Date: 30-Sep-2000
Scientific Officer: Yoon Park

Objective:
To increase the time-bandwidth product of present delay line technology
and analog communication links by using fiber optics and related
componentry.
Approach:
IR fibers and cable/AR coating will be developed. Purification and
fiberization techniques will be developed to reduce the glass-cladd fiber loss to <0.3dB/m and increase the average fiber bend strength to >100kpsi. Ruggedized, vibration-proof cables which can tolerate the
environmental conditions expected in harsh environment will be investigated.
Progress:
Glass cladd chalcogenide fibers have been developed, AR-coated and
successfully used in the lab for IR jamming of missile seeker at Sanders. The IR cables are required for the Tri-Service ATIRCM Program for aircraft protection. In this system, the IR fiber is needed to connect the ATIRCM laser to the Jam Head, and thus replace the current Optical Coupler, which is cumbersome, heavy and difficult to align. Because of the importance of fiber for the ATIRCM program, the NRL IR fiber effort is currently being supported by the U.S. Army CECOM. NRL has a CRADA with Corning, Inc. for IR fiber amplifier development.

Title: Mid-IR Type-II Quantum Well and Interband
Cascade Lasers
PI: Jerry Meyer
NAVAL RESEARCH LABORATORY
Optical Sciences Division
Address: Code 5613
Washington, DC 203755338
(202) 767-3276
Funding Agency: Office of Naval Research
PR Number: 00PR00496-00
Award Number: N0001400WX20321
Current End Date: 30-Sep-2000
Scientific Officer: Yoon Park
Objective:
To develop two new mid-IR sources, the type-II quantum well laser and
the type-II interband cascade laser, which are projected to produce on
the order of 1 W quasi-cw output power per facet at ambient or TE-cooler
operating temperatures with near-diffraction-limited beam quality.
Approach:
Two new semiconductor mid-IR sources, the type-II quantum well
laser (T2QWL) and the type-II interband cascade laser (T2ICL), which
overcome the disadvantages of previous type-I and type-II approaches,
and will consequently produce higher output powers at higher operating
temperatures. A four-constituent (InAs-GaInSb-InAs-GaALSb) structure
will be utilized. This structure is expected to be superior to the type-II superlattice(SL) because it displaces 2D dispersion relations for both electrons and holes.
Progress:
Electrically-pumped mid-IR lasers with type-II superlattice active
region have yeilded record operating temperatures, pulsed output powers, and threshold current densities. The maximum power of 430 mW at 100 K is near the highest observed for interband diodes at 2.9 um, and the peak output of 100 mW at 200 K is higher than any previous result for > 2.9 um. The threshold current density was as low as 120 A/cm2 at 80 KK, and for all T>180 K the threshold current density values were the lowest ever reported for this wavelength range (e.g., 1.1 kA/cm2 at 200 K).

Title: Optical Receivers
PI: Ronald Esman
NAVAL RESEARCH LABORATORY
Code 5672
Address: 4555 Overlook Ave
Washington, DC 203755320
(202) 767-9359
Funding Agency: Office of Naval Research
PR Number: 00PR00497-00
Award Number: N0001400WR20052
Current End Date: 30-Sep-2000
Scientific Officer: Yoon Park
Objective:
To develop high-current photodetectors for use in state-of-the art
photonic systems. This program emphasizes high current photodetectors and photodetectors interfaced with electronics(OEICs).
Approach:
Devices capable of detecting greater than 50 to 100 mA at 5 to 20 GHz
and 100 to 200 mA below 5 GHz will be designed and fabricated. These
devices will transition into various specific photonic systems which will perform more effectively than current electronic systems as well as
providing new and advanced capabilities.
Progress:
Have achieved <4V Vpi at 20 GHz at 1.3 micron in etched ridge device.
Tunable laser tuning range extended to 22 nm with the following paramters: 4.5 linewidth enhancement factor, 20 mA threshold, 0 dBm
into the fiber, >45 dB SMSR. Longterm wavelength stability of SSG-DBR
lasers was investigated indicating degradation leading to unacceptable
mode hops (~5nm). Tuning algorithms to mitigate this degradation were
developed and successfully tested. Long term verification of this concept is underway.

Title: Optical Transmitters
PI: Ronald Esman
NAVAL RESEARCH LABORATORY
Code 5672
Address: 4555 Overlook Ave
Washington, DC 203755320
(202) 767-9359
Funding Agency: Office of Naval Research
PR Number: 00PR00498-00
Award Number: N0001400WX20091
Current End Date: 30-Sep-2000
Scientific Officer: Yoon Park
Objective:
To increase the time-bandwidth product of present delay line technology and analog communication links by using fiber optics and related componentry.
Approach:
To increase the time-bandwidth product of delay lines the bandwidth
of the components used in the delay line, namely; the laser diode
transmitter and the p-i-n diodes photodetector are being increased. The
development of the optical amplifier at 1.3 um and 1.5 um makes it
necessary to develp components and systems at these wavelengths.
Progress:
Initial studies of Sampled Grating, Distributed Bragg Reflector (SGDBR)
lasers indicate that they represent a very promising technology. They
have a very good spurious mode suppression ratio (MSR>40dB), output
powers on the order of 10 mW, and tuning ranges of up to 80 nm. Static characterization of the SGDBR devices shows relatively well-behaved CW operation. Approximately 10 mW CW power is available from this device. Have achieved <4V Vpi at 20 GHz at 1.3 micron in etched ridge device. Tunable laser tuning range extended to 22 nm with the following paramters: 4.5 linewidth enhancement factor, 20 mA threshold, 0 dBm into the fiber, >45 dB SMSR. Long term wavelength stability of SSG-DBR lasers was investigated indicating degradation leading to unacceptable mode hops (~5nm). Tuning algorithms to mitigate this degradation were developed and successfully tested. Long term verification of this concept is underway.

Title: High Power 2.0 and 1.5um Fiber Source
PI: Lew Goldberg
NAVAL RESEARCH LABORATORY
Department of Physics
Address: Washington, DC 203755000
(202) 767-9079
Funding Agency: Office of Naval Research
PR Number: 00PR00500-01
Award Number: N0001400WR20114
Current End Date: 30-Sep-2000
Scientific Officer: Yoon Park

Objective:
To develop high-power fiber amplifiers and lasers for use in remote
sensing and laser countermeasure applications. The proposed research
will result in high efficiency and compact fiber-based coherent optical
sources suitable for use in 1.5 um eye-safe remote measurement systems
such as micro-Doppler and LSADAR and as a 2.0 um pump for mid-IR
optical parametric oscillator for laser countermeasure applications.
Approach:
The laser systems will rely on the use of optical fiber gain medium. The propagation loss of a silica fiber is approximately 10dB/km at 2.0 um. For typical fiber lengths of few tens of meters, the propagation loss in silica fiber at 2.0 um is therefore negligibly small. In the proposed 2.0 um fiber laser, a Tm doped fiber is pumped by a 1.5 um fiber laser constructed using a double cladding fiber containing a large Er/Yb co-doped core. The Er/Yb co-doped fiber laser is cladding-pumped by fiber-coupled 980 um laser diode bars.
Progress:
Tm doped fibers and crystals were characterized to determine their slope
efficiency when pumped by 800 nm light. Based on these measurements a preliminary Tm doped fiber preform design was finalized and fabrication was initiated. The fiber preform was designed to have cladding ratio and doping concentration compatible with a double cladding fiber. Fiber amplifier based on double cladding fibers and side-pumping through a V-groove were demonstrated, generating up to 1.7 W at 1.5 um and 4 W at 1um. Record electrical-to-optical conversion efficiencies (42% for a Yb doped fiber amplifier) were demonstrated.

Title: 3-Band IRFPA Technology
PI: Joseph Omaggio
NAVAL RESEARCH LABORATORY
Code 6810
Address: 4555 Overlook Avenue SW
Washington, DC 20375
(202) 767-9184
Funding Agency: Office of Naval Research
PR Number: 00PR00502-01
Award Number: N0001400WX20197
Current End Date: 30-Sep-2000
Scientific Officer: Yoon Park
Objective:
To develop the technology for three band imaging, staring, infrared focal plane arrays. These focal planes detect in three bands in the 3-12 micron part of the IR spectrum.
Approach:
A three stacked photodiode approach to be pursued. In this approach
the widest bandgap diode detects photons with energies up its semi-conductor bandgap and acts as a filter on the high wavelength end
for the next two diodes. Only band 2 and 3 radiation is transmitted.
Diode number 2 detects radiation in band 2 and transmits band 3
radiation which is detected in diode 3. This results in three co-located detectors which detect in distinctly different IR bands.

Title: ENHANCED SIGNAL PROCESSING ON THE FOCAL
PLANE ARRAY
PI: Ken Sarkady
NAVAL RESEARCH LABORATORY
Code 5635
Address: 4555 Overlook Avenue SW
Washington, DC 20375
(202) 767-5899
Funding Agency: Office of Naval Research
PR Number: 00PR00508-00
Award Number: N0001400WX20340
Current End Date: 30-Sep-2000
Scientific Officer: Yoon Park

Objective:
To develop adaptive IRFPAs with on-chip electronics to enhance the
dynamic range to 120 dB, and to implement offset and nonuniformity
correction. Increased dynamic range is required for Background Limited
Infrared Performance(BLIP) in long-wave IRFPA's and to enable either
mid-wave or long-wave IRFPA's to adapt to varying backgrounds such as
cold sky and hot desert.
Approach:
The work involves current subtraction at the detector integration site
where the value of current subtracted is unique for each pixel and is
programmed by off focal plane electronics. This technique will allow
compensation for detector and MOSFET threshold nonuniformities at the integration site thus relieving dynamic range requirements on down
stream analog electronics.
Progress:
Two FPAs were hybridized and tested in a laboratory dewar using a
laboratory test set. Since the use of the laboratory test did not allow
adaptive loop closure the adaptive FPA was operated in an open loop
mode. In this mode a factor of three improvement in integration time
(two-three in sensitivity) was demonstrated. The remaining camera
boards were fabricated and tested. Currently the camera electronics are
integrated with the FPA.

Title: Internal High-Speed Laser Modulation
PI: Michael Shur
RENSSELAER POLYTECHNIC INSTITUTE
Address: Thornton Hall
Charlottesville, VA 22903
(804) 942-4270
Funding Agency: Office of Naval Research
PR Number: 00PR00510-00
Award Number: N000149810075
Current End Date: 31-Dec-2000
Scientific Officer: Yoon Park

Objective:
The proposed project will focus on developing a new device
technology for high-speed internal modulation in semiconductor
heterostructure lasers. This technique is based on the concepts of
vertical and lateral Modulation Shutter(MS) implemented in the novel
semiconductor ridge waveguide laser with lateral current injection.
Approach:
Modulation Shutters are controlled by external voltage and are
designed to suppress stimulated emission in quantum well laser
heterostructure by introducing lossy sections "shutter" into the active
region. Since very small fractions of the active region are involved,
dramatic increase in the modulation frequency and higher modulation
linearity, which is critical for analog circuit applications, is expected.
Progress:
Proof of the concept modulation of the LCI laser output by split
electrodes was demonstrated at low temperatures. N Fabrication process
has been optimized and now it is possible to stop etch on GaAs contact
layer laying at the distance 40 nm above InGaAs active region. Diffusion from spin-on Zn doped silicon dioxide by open tube diffusion was performed on test GaAs semi-insulating samples and on a piece of LCI
laser epi-wafer. Results of the diffusion at 750C indicate that this
diffusion procedure is able to intermix active region layers and dope
p-region to a concentration as high as 5E18 cm-3. Measurements of the
LCI laser sample and new diffusion runs on the rest of the samples is in progress.

Title: Uncooled Photon Detector for IR Imaging
PI: Manijeh Razeghi
NORTHWESTERN UNIVERSITY
Department of Electrical Engineering &
Computer Science
Address: 225 N. Campus Drive
Evanston, IL 602083118
(847) 491-7251
Funding Agency: Office of Naval Research
PR Number: 00PR00511-00
Award Number: N000149910630
Current End Date: 30-Apr-2002
Scientific Officer: Yoon Park

Objective:
The realization of high performance uncooled infrared photo detectors
by the growth of low dimensional structures. The possibility of
multi-color detectors with these low dimensiional structures is to be
investigated.
Approach:
The use of quantum-dot (QD) structure for infrared detectors will be
pursued. The design and fabrication of quantum dot infrared detector
of both type-I and type-II band align schemes will be attempted by MBE
and MOCVD. This can significantly (or almost completely) suppress the
optical phonon-relaxation for intersubband system or Auger
recombination rate (for infrared system).
Progress:
Uncooled infrared detectors in the mid and long wavelength ranges have
been developed using InAsSb/AlInSb heterostructures on GaAs substrates. The detectors show the maximum reported detectivity of 1x108 cmHz1/2/W at 8mm at room temperature without any optical immersion or passivation. The detectivity improved by more than one order of magnitude after optical immersion. Also demonstrated was the first growth of InTlSb and room temperature operating 8-11 ?m photoconductors on GaAs. Demonstrated room temperature operating 8-12 ?m InSbBi photoconductors on GaAs. Recently, infrared photoresponse up to 15 ?m was obtained from III-V quaternaries such as InAsSbBi and InTlAsSb.

Title: Optical Amplifiers & Light Emitters for
Integrated Optoelectronics
PI: Dietrich Langer
UNIVERSITY OF PITTSBURGH
Dept. of Electrical Engineering
Address: 350 THACKERAY HALL
PITTSBURGH, PA 15260
(412) 624-9663
Funding Agency: Office of Naval Research
PR Number: 00PR00513-00
Award Number: N000149910663
Current End Date: 30-Apr-2002
Scientific Officer: Yoon Park

Objective:
To develop the design of devices, the appropriate material and the
appropriate processing technology for such optoelectronic components
that lend themselves to integration.
Approach:
To develop opto-electronic components which are suitable for monolithic
integration on a single substrate, fabrication of various guided-optics
devices, such as waveguide lasers, amplifiers and splitters, all based on low-loss silicate glass doped with or without erbium.
Progress:
Preliminary parameters for the deposition of semiconducting and insulating films have been established. These included GaN and ZnO
films on silicon or sapphire substrates for development of various
functional devices based on wide bandgap materials. Both Prof. Langer
and Prof. Kim attended and contributed to the WOFE'99 Conference.
An updated version of earlier computer programs for the design of
optical waveguides was obtained and is being adapted.

posted 06-07-2002 02:23 PM            

Title: III-V Nitride UV Detector Arrays Fabricated
by Combining HVPE Lateral Epitaxial
Overgrowth and MBE Methods
PI: Theodore Moustakas
THE TRUSTEES OF BOSTON UNIVERSITY
College of Engineering
Address: 44 Cummington St, 4th Floor
Boston, MA 02215
(617) 353-5431
Funding Agency: Office of Naval Research
PR Number: 00PR00518-00
Award Number: N000149910309
Current End Date: 31-Jan-2002
Scientific Officer: Yoon Park
Objective:
To fabricate large area p-i-n GaN/AlGaN heterojunction UV
photodetectors and photodetector arrays with very low dark current,
high responsivity and large visible light rejection.
Approach:
Very low dark currrent devices will be obtained through the
development of low threading dislocation and large area GaN uniform
substrates or arrays by the Lateral Epitaxial Overgrowth (LEO) approach
using HVPE method. These substrates will be used for the homoepitaxial
growth of the p-AlGaN, i-GaN and n-GaN by the MBE method.
Progress:
Several oxide VCSEL epitaxial designs were optimized for single-mode
emission, then grown and processed with wide parameter variations.
Larger-aperture devices were multi-mode and were superior to all other
multi-mode VCSELs in fiber coupling. This design was chosen for
Picolight's 850nm fiber optic products. Other designs were inferior.
Only very small apertures (<4um) were single-mode. High stress
reduced the higher-order modes. Progress was made in 1300nm
VCSELs in this program and separately. Scaling favors single-mode
output at 1300nm compared to 850nm. Based on progress so far, we
expect to exceed the originally proposed goal of a 1300nm VCSEL
emitting 1mW, single-mode at 85 degrees C.

Title: JSEP FELLOWSHIP FOR WILLIAM WEEKS
PI: Kenneth Jenkins
THE BOARD OF TRUSTEES OF THE UNIVERSITY
OF ILLINOIS AT URBANA CHAMPAIGN
Coordinated Science Laboratory
Address: 1101 West Springfield Avenue
Champaign, IL 61820
(217) 333-2510
Funding Agency: Office of Naval Research
PR Number: 00PR00521-00
Award Number: N000149810064
Current End Date: 22-Sep-2000
Scientific Officer: Colin Wood
Objective:
Improve data retrieval from 2 dimensional storage media.
Approach:
Recognizing the similarities in mathematics of full surface storage
devices and those of phase transition problems and using models of
theoretical physics, 2 dimensional modulation codes will be developed
for optimized low latency data retrieval from optical digital storage
media.
Progress:
Progress was made in the first year of this JSEP fellowship. Report
will be submittered on Oct 1 for inclusion in JSEP progress reports
section.

Title: Highly linear, high Power Amplifiers with
6-18 GHz Bandwidth
PI: Brian Thibeault
WIDEGAP TECHNOLOGY LLC
Address: 6266 Marlborough Drive
Goleta, CA 93117
(805) 967-9433
Funding Agency: Office of Naval Research
PR Number: 00PR00540-00
Award Number: N0001498C0013
Current End Date: 09-Dec-2000
Scientific Officer: John Zolper

Objective:
Under this contract high-power 6-18 GHz amplifiers will be developed using AlGaN/GaN HEMTs. Maximum achievable power from a single amplifier and from a module will be demonstrated. Ultralinear device designs will also be explored.
Approach:
Under this contract four areas will be explored: 1) Traveling wave
amplifier with a suppressed backward wave will be designed, 2) Class B
quasi-complementary amplifier unit cells will be designed, 3) AlGaN/GaN HEMTs will be constructed and packaged in flip-chip carriers, and 4) efficient power combining will be implemented in the 5-20 GHz range.
Progress:
In the first 3 quarters of the program, feasible device designs,
processing technologies and scaling laws for large periphery devices
have been established and produced state-of-the-art, up to 6-mm-wide,
devices. 4-mm device achieved 5-W output power along with 53% PAE
at 4 GHz, while a 6-mm transistor exhibited 6-W output power with
33% PAE. Both output powers are believed to be the highest reported to
date for GaN FETs. The first linearity measurements of GaN HEMTs were
also conducted at WiTech and pointed to excellent potential. Broad-band amplifiers were designed using both the resistive-feedback scheme and the lossy input-match scheme, and are ready for mask layout.

Title: InP-Based Pulsed W-Band IMPATT Transmitter
Technology
PI: Marko Afendykiw
NAVAL AIR WARFARE CENTER WEAPONS
DIVISION
RF Guidance & Analysis Branch
Address: Code 087
China Lake, CA 935556001
(619) 939-2845
Funding Agency: Office of Naval Research
PR Number: 00PR00541-00
Award Number: N0001400WX20090
Current End Date: 30-Sep-2000
Scientific Officer: John Zolper

Objective:
Seeks means of providing W-band signals with solid state technology so
as to be adaptable to missile front end configurations. At present the
focus is on the development of IMPATT devices capable of 4 watts peak
power at 30% duty and 300nS pulse waveform. This is mostly an in-house effort supported by an industrial supply of diodes and a companion university modeling effort.
Approach:
Diamond thermal heat spreaders and novel rectangular cavities will be
used to provide IMPATT performance and efficiency of at least 4 watts
peak power in 300 nanosecond pulses per diode. New IMPATT diodes and materials will be explored to achieve the 4 watts of output power.
InP IMPATTs will be emphasized in FY97 with a goal to increase the
output of GaAs IMPATT designs by a factor of 8. Work on IMPATT diode
combiners will continue in the direction of assembling and testing a 21
watt peak IMPATT transmitter using previously developed 1.4 watt IMPATT devices.
Progress:
Work has focused on the development of InP IMPATT diodes at 35 and
94 GHz since InP should out perform GaAs devices. Initial IMPATT wafer
were grown at the University of Texas and process technology was developed at Raytheon. The initial InP devices had incorrect doping
profiles due to Sn diffusion. This has been overcome in subsequent
runs by modifying the growth sequence. P-ohmic contacts were demonstrated at Raytheon with a specific contact resisitance of ~5e-7
ohms-cm2 using Rh-Au contacts on p+ InGaAs.

Title: OPTICAL AND STRUCTURAL PROPERTIES OF
LATERAL EPITAXIAL GaN LAYERS FOR POWER
MICROWAVE DEVICES
PI: Jaime Freitas
NAVAL RESEARCH LABORATORY
CODE 6874
Address: 4555 OVERLOOK AVENUE S. W.
WASHINGTON, DC 203755347
(202) 404-4536
Funding Agency: Office of Naval Research
PR Number: 00PR00543-00
Award Number: N0001400WX20089
Current End Date: 30-Sep-2000
Scientific Officer: Colin Wood
Objective:
PI will characterize GaN films grown by three ACI competitors on Si
for optical and electrical behaviour.
Approach:
PI will use photo, and cathodo-luminescence techniques for optical
characterization, and Hall, and C-V for electrical measurements.
Progress:
The structural, optical, and electronic properties of lateral epitaxial
overgrown (LEO) GaN films deposited on Si substrate by three university -based crystal growth have been evaluated. Screening and assessment of materials received from these universities with optical techniques consisting of Raman scattering (RS) for structural information and photoluminescence (PL) spectroscopy for electronic information is employed. Techniques such as optical microscopy, spatially resolved PL and cathodoluminescence (CL), and real-color CL to establish the morphological/areal variation of the electronic properties of the overgrown layer are also used. Although each University team has made great progress, problems remain. The film morphology of the continuous layers precludes the use of the LEO-GaN/Si for free-standing GaN sustrate as well as for device fabrication. In addition, the present lack of control of the intrinsic electronics properties of these
continuous layers and the uncoalesced layers will make very difficult
the fabrication of high yield electronic devices.

Title: GaN LATERAL EPITAXIAL OVERGROWTH ON SILICON
FOR AFFORDABLE POWER MICROWAVE DEVICES
PI: Steven Denbaars
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA SANTA BARBARA
Materials Dept. College of Engineering
Address: Cheadle Hall, Room 3227
Santa Barbara, CA 93106
(805) 893-8511
Funding Agency: Office of Naval Research
PR Number: 00PR00544-01
Award Number: N000149810401
Current End Date: 30-Sep-2000
Scientific Officer: Colin Wood

Objective:
To develop an inexpensive supply of 'zero-defect' GaN semiconductor
epitaxial films.
Approach:
Using a GaP lattice matched buffer and newly developed epitaxial
layer overgrowth, GaN epitaxial films will be deposited by metal-organic
chemical vapor growth.
Progress:
As a result of surface partitioning and other surface preparation
techniques, the PI has developed the best transferable technology for
transitioning epitaxial GaN on Si to EMCORE LTD.

Title: Epitaxial Layer Overgrowth of II-VI
Semiconductors
PI: Ishwara Bhat
RENSSELAER POLYTECHNIC INSTITUTE
Center for Integrated Electronics
Address: Troy, NY 12180
(518) 276-2786
Funding Agency: Office of Naval Research
PR Number: 00PR00545-00
Award Number: N000149810767
Current End Date: 15-Aug-2000
Scientific Officer: Colin Wood

Objective:
To extend the useful IR wavelength of HgCdTe detector arrays for
FLIR application.
Approach:
Lateral epitaxy on pattered substrates of Si will be used for
nucleation and deposition of CdTe, and subsequently CdZnTe, and
eventually HgCdTe films with several orders of magnitude reduction in
defect densities.
Progress:
Student hired, and SiO2 masked silicon substrate templates for LEO
growth have been ordered. Conditions for nucleation on Si are being
investigated.

Title: High Power Broadband Amplifiers for 1-18
GHz Naval Radar
PI: Mark Rodwell
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA SANTA BARBARA
Department of Electrical and Computer
Engineering
Address: CHEADLE HALL ROOM 3227
Santa Barbara, CA 93106
(805) 893-3244
Funding Agency: Office of Naval Research
PR Number: 00PR00546-00
Award Number: N000149810750
Current End Date: 30-Sep-2001
Scientific Officer: John Zolper

Objective:
To demonstrate a solid state power amplifier producing 2 Watts of
power over 1 -18 GHz. This will serve as the driver stage for a Microwave Power Module under development by NRL.
Approach:
Both circuit and transistors improvements will be addressed to
achieve the desired broadband power amplifier performance. Circuit
work will include a cascode-delay-matched traveling-wave amplifier and
resistive-feedback Ft-doubler configurations. The circuits will initially be implemented with InP-based transfer substrate HBTs and latter, as the device technologies mature, GaN HEMTs and HBTs.

Title: Millimeter-wave AlGaN/GaN HEMT Power
Amplifier Technology
PI: Yifeng Wu
NITRES INC
Address: 5655 Lindero Canyon Rd STE 404
Westlake Village, CA 91362
(805) 967-9433
Funding Agency: Office of Naval Research
PR Number: 00PR00548-00
Award Number: N0001400C0004
Current End Date: 31-Oct-2002
Scientific Officer: John Zolper

Objective:
Develop AlGaN/GaN high electron transistors for power generation up to
35 GHz.
Approach:
AlGaN/GaN high electron transistor power performance will be
extended up to 35 GHz by device scaling and implementation of a
recessed gate technology.

Title: MICROWAVE POWER MODULE
PI: Richard Abrams
NAVAL RESEARCH LABORATORY
Code 6844
Address: 4555 Overlook Ave S.W.
Washington, DC 203755347
(202) 404-7163
Funding Agency: Office of Naval Research
PR Number: 00PR00552-00
Award Number: N0001400WX20103
Current End Date: 30-Sep-2000
Scientific Officer: Ingham Mack

Objective:
Develop compact, lightweight, highly efficient and affordable RF
transmitters that will enable new Navy and defense system applications,
yet be suitable for retrofit or mid-life upgrades of existing electronic
attack, radar, and communication systems.
Approach:
Investigate the scientific issues and trade-offs relevant to the MPM's
capability to deliver high power with extremely high efficiency and high
linearity across broad bandwidths. Develop the power module RF trans-mitter technology base to exploit the best features of solid-state
and vacuum-electronics technology. Demonstrate microwave and milli-meter-wave power module technology with various capabilities of
interest to electronic warfare, radar, and communication systems and applications.
Progress:
Northrop Grumman Corp. designed, fabricated, and characterized a
vacuum power booster that produced 100-watt (CW) from 3- to 18-GHz;
they will extend the frequency performance to 2 GHz, using harmonic
injection techniques. Lockheed Martin/Sanders established harmonic
injection proof-of-principle as a technique to reduce harmonic output
power; they will develop a brass-board version of a 2- to 18-GHz MPM
using a Litton vacuum power booster. Northrop Grumman defined the
benchmark 2-D array architecture and three candidate architectures
using MPMs and will complete a preliminary analysis of these arrays.
The non-linear large signal code CHRISTINE was validated for efficiency
optimization at Northrop Grumman Corp.

Title: SUPPORTING TECHNOLOGY
PI: David Abe
NAVAL RESEARCH LABORATORY
CODE 6843
Address: 4555 OVERLOOK AVENUE SW
WASHINGTON,, DC 203755347
(202) 767-0033
Funding Agency: Office of Naval Research
PR Number: 00PR00556-00
Award Number: N0001400WX20152
Current End Date: 30-Sep-2000
Scientific Officer: Ingham Mack

Objective:
Develop new materials and technologies that can be used to extend
the performance of broad classes of vacuum power amplifiers.
Approach:
Materials for vacuum electronic power devices will emphasize the
development of materials to replace toxic BeO-SiC as well as develop
new materials to enable vacuum electronic devices to operate at
increased power densities. Noise reduction in linear beam amplifiers
will be addressed through theoretical and experimental investigations of
ion-relaxation noise, one of the most common sources of noise in CW
linear beam tubes.
Progress:
HPCS conformal SiC coatings have been produced with tailored electro-magnetic loss properties using additives (carbon black, dendritic
copper). The coatings exhibit acceptable adherence to copper RF cavity walls and excellent high vacuum properties down to 10-9 torr. Cavity Qs
as low as 34 have been achieved in S-band, demonstrating that the material has potential as an alternative to BeO-SiC for bandwidth
control in vacuum amplifiers. AlN composites with thermal conductivities as high as 204 W/m-K have been produced by microwave
sintering with a factor of four improvement in processing time. In a
second task, an ion noise model for the AEGIS AN/SPG-62 coupled-cavity TWT has been developed for the 2-D particle-in-cell code, OOPIC. Simulations are continuing and in the process of being compared with experiment.

Title: HIGH PERFORMANCE MILLIMETER WAVE DEVICES
PI: Bruce Danly
NAVAL RESEARCH LABORATORY
Code 6840
Address: 4555 Overlook Ave SW
Washington, DC 20375
(202) 767-0032
Funding Agency: Office of Naval Research
PR Number: 00PR00557-01
Award Number: N0001400WX20185
Current End Date: 30-Sep-2000
Scientific Officer: Ingham Mack

Objective:
Explore and develop high power millimeter wave vacuum electronic
amplfiiers having enhanced gain, bandwidth, and efficiency with reduced physical and operational constraints. Power level requirements are system and frequency specific, spanning watts to thousands of kilowatts in the MMW frequency band.
Approach:
Fast-wave devices that include gyrotrons with reduced size and weight with higher efficiencies than can be achieved in currently-available devices will be developed. Strong emphasis will be placed on coupling of theory with experiment. Slow-wave devices that address system-specific needs for the Army are being developed through Project Reliance agreements.
Progress:
The first testing of the 94-GHz high average-power gyro-klystron
amplifier has been completed. A team composed of NRL, Litton,
Communication and Power Industries, and University of Maryland
developed this amplifier. In low-duty testing, this amplifier achieved 115 kW peak power and 600 MHz instantaneous bandwidth. In high duty
testing, the device achieved 10.1 kW average power, 90 kW peak power,
at an efficiency of 33% (RF power divided by input power). Development
of subsequent devices with wider bandwidth, and for airborne and
space-based platforms is underway.

Title: MODELING AND SIMULATION
PI: Baruch Levush
NAVAL RESEARCH LABORATORY
code 6841
Address: 4555 Overlook Ave SW
Washington, DC 203755347
(202) 767-0003
Funding Agency: Office of Naval Research
PR Number: 00PR00558-00
Award Number: N0001400WX20153
Current End Date: 30-Sep-2000
Scientific Officer: Ingham Mack

Objective:
Develop an advanced computer-based capability for vacuum electronic devices (VEDs) to enhance design, development, and manufacture, resulting in higher performance and reliability with lower costs and shorter development times. The activities in this project will support the on-going development of the vacuum power booster for the Microwave Power Module(MPM) project, as well as development of fast-wave and slow-wave devices in the High-Power Millimeter-Wave Project. Military applications in radar, electronic warfare, and communications depend on the successful execution of these projects. This project will also investigate new techniques that offer promise for improving the performance of CFAs for the AEGIS SPY-I system while maintaining or reducing present life cycle costs.
Approach:
This project will establish a new design methodology that will be
applied to a sequence of vacuum electronic devices over the next five
years. The initial three-year effort will focus primarily on tools to design helix TWTs and crossed-field amplifiers through the development of three-dimensional, unstructured-grid codes for gun and collector
design, for cold-test, and for large-signal analysis. The long-term plan calls for the three dimensional large-signal code to be extended to
coupled-cavity TWTs and klystrons. These three-dimensional codes will
also enable stability studies of linear TWTs as part of an overall design methodology based on numerical simulation.
Progress:
An accurate model for the tape helix has been developed, implemented
and tested in the 1-D large signal code (CHRISTINE) for modeling helix
TWTs. A modified Jacobi-Davidson method has been implemented in the 3-D electromagnetic code (CTLSS) enabling it to find eigen-modes of electro-magnetic cavities containing RF absorbing dielectric materials. Fast parametric codes for designing periodic permanent magnet circuits
for TWTs have been developed. The development of a 3-D gun/collector
electrostatic code (MICHELLE) based on an unstructured numerical
mesh has been initiated.

Title: ADVANCED EMITTER TECHNOLOGY
PI: Keven Jensen
NAVAL RESEARCH LABORATORY
Code 6841
Address: 4555 Overlook Ave SW
Washington, DC 203755347
(202) 767-3114
Funding Agency: Office of Naval Research
PR Number: 00PR00559-00
Award Number: N0001400WX20102
Current End Date: 30-Sep-2000
Scientific Officer: Ingham Mack

Objective:
Investigate electron sources and advanced cold cathodes for high
power RF sources characterized by higher current density, lower
emittance, more uniform emission, and greater robustness in a power
tube environment for the purpose of providing higher efficiency, lower
noise, and longer operating life for vacuum electronic devices.
Approach:
Develop advanced thermionic (scandate) cathode technology by developing fabrication techniques for scandate cathodes and transferring the process to industry; evaluate, characterize, and life test fabricated scandium cathodes; idenfify the scandate cathode emission and failure mechanism. Develop advanced cold cathodes by characterizing the transport properties of emitter materials, with emphasis on wide bandgap materials; investigate electron injection mechanisms and develop theoretical models of injection, transport and emission. Develop secondary emission cathode materials by resolving performance limits in BeO cathodes, investigate diamond and alternative emitter materials, and investigate the secondary emission process.
Progress:
An emission test vehicle has been designed, constructed and tested.
Homogenous coatings of rhenium and Sc2O3 have been successfully deposited on the surface of dispenser cathodes using a magnetron sputter-coater equipped with a unique segmented foil target and rotating holder. The scandium component is then oxidized prior to activation. In initial tests of the coated cathodes, emission current densities of up to 53 A/cm2 have been measured in pulse mode at an anode potential of 1,200 volts and a temperature of 1050oCMoBr. A patent disclosure has been filed to protect the technology if deemed appropriate.

Title: Defect Reduction in A1GaN/GaN Ultravoilet
Photodetectors
PI: Hadis Morkoc
VIRGINIA COMMONWEALTH UNIVERSITY
Dept. of Electrical Engineering &
Physics
Address: 601 West Main Street
Richmond, VA 23284
(217) 333-0722
Funding Agency: Office of Naval Research
PR Number: 00PR00567-00
Award Number: N000149910628
Current End Date: 30-Apr-2002
Scientific Officer: Yoon Park

Objective:
To develop the materials and processing technologies for high performance UV AlGaN/GaN photodetectors that can be integrated into UV focal plane-arrays.
Approach:
Initial detectors would be of GaN pin variety to establish base line
figures for detectivity and noise. For the solarblind region of the
spectrum, considering the difficulties associated with p-type doping,
Schottky barrier varieties will be explored. In parallel doping schemes, such as modulation, doping will be explored in effort to develop pin varieties for the solar blind region also.
Progress:
A frontal attack has been launched to prepare GaN, AlN and AlGaN on
saphire and SiC substrates for reducing point defects utilizing PL and
CL, high resolution X-Ray diffraction and AFM. One of the MBE systems is being equipped with diagnostics and parameter control apparatus for precise control of all the critical parameters. The MOCVD system is nearly up with some heat damage to the sample holder.

Title: Picosecond Time-Resolved Photoluminescence
Studies of III-Nitride Materials and
Structures
PI: Jiang Hongxing
KANSAS STATE UNIVERSITY
Dept. of Physics
Address: Anderson Hall, Room #10
Manhattan, KS 66506
(785) 532-1627
Funding Agency: Office of Naval Research
PR Number: 00PR00568-00
Award Number: N000149910444
Current End Date: 31-Mar-2002
Scientific Officer: Yoon Park

Objective:
To address the fundamental issues which have not yet been fully explored but are proven to profoundly influence GaN/AlGaN Quantum Well and heterojunction device performance: 1) alloy dependent optical and optoelectronic properties of AlGaN epilayers with high AlN fractions
and 2) structural parameter dependent optical transitions and carrier
dynamics in GaN/AlGaN QWs and heterostructures.
Approach:
Picosecond time-resolved photoluminescence will be employed to study optical transitions and carrier dynamics in GaN/AlGaN QW structures and mechanisms of optical transitions in AlGaN epilayers with high AlN mole fractions. The results of the research will provide input for developing suitable materials quality and device designs for applications such as UV detectors, UV emitters, field effect transistors, and electron emitters.
Progress:
The III-nitride microdisc and microrings have been fabricated by
inductively-coupled-plasma dry etching from GaN/AlGaN and InGaN/GaN multiple quantum well (MQW) structures. With respect to the original MQWs, the intrinsic transitions from both the wells and barriers exhibited an approximate 10-fold increase in both recombination lifetime and quantum efficiency upon formation of microdiscs. Optical resonance modes have been observed in GaN microstructures. Preliminary results imply a bright future for III-nitride micro-size optoelectronic devices, including micro-LEDs, micro-LED arrays, microcavity lasers, and vertical cavity surface emitting lasers.

Title: Analog Signal Processing Devices and
PI: Fritz Kub
NAVAL RESEARCH LABORATORY
Code 6813
Address: 4555 Overlook Avenue SW
Washington, DC 203755347
(202) 767-3862
Funding Agency: Office of Naval Research
PR Number: 00PR00577-02
Award Number: N0001400WX20051
Current End Date: 30-Sep-2000
Scientific Officer: Ingham Mack

Objective:
Develop high frequency adaptive processor circuits for application to
a variety of Navy system needs with particular emphasis on co-site interference cancelers for application to surveillance, communications,
and jammer systems. Develop a Continuous Wavelet Transform (CWT)
circuit to reduce the volume and power, compared to a digital approach,
that can be applied to communications and EW applications. Develop
high dynamic range photodetector/amplifier arrays that can be used in
acousto-optic channelizers for EW applications.
Approach:
Techniques to realize high frequency adaptive processor circuits using CMOS VLSI technology will be developed. Continuous time tapped delay lines coupled with on-chip offset correction circuitry will be used to implement the LMS algorithm. Techniques to realize the recently-invented analog Continuous Wavelet Transform (CWT) circuit as well as the photodetector/amplifier arrays using CMOS VLSI technology will also be developed.

Title: INFRARED SPATIAL INTERFEROMETRY
PI: Charles Townes
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA BERKELEY
SPACE SCIENCE LABORATORY
Address: 336 SPROUL HALL
BERKELEY, CA 947207450
(510) 642-1128
Funding Agency: Office of Naval Research
PR Number: 00PR00601-01
Award Number: N000149610737
Current End Date: 31-Dec-2000
Scientific Officer: Edward Kennedy

Objective:
The Navy has national responsibility for the position measurements of
stars and other astronomical objects for the purpose of precise navigation. In addition, understanding fluctuations in the atmosphere
aid in the imaging and transmission of optical and infrared waves
through the atmosphere.
Approach:
A third telescope is being added to enable phase closure measurements.
In addition thermal measurements along the optical paths and acoustic
radar measurements of the fluctuations in the path are being added to
the data collection to better understand the effects on imaging and
propagation of infrared waves through the atmosphere.
Progress:
The two-telescope interferometer on Mt. Wilson has been operating well,
with upgrades made last and this year. A very recent upgrade allows the
telescope to be opened or closed by a single operator, rather than
requiring two persons. Another involves new computer programming which increases flexibility of the system. A graduate student has completed his work and a second will finish during the summer of 1999. One new graduate student has entered the program. Interferometry on spectral lines was carried out and has yielded important new information about formation of molecules around stars. Installation commencing shortly on a new base for the telescope to approximately double the baseline length available.

Title: HF Heater to ELF/VLF Conversion Studies
PI: Harvey Rowland
NAVAL RESEARCH LABORATORY
Plasma Physics Division
Address: ATTN CODE 3310
Washington, DC 203755320
(202) 767-6644
Funding Agency: Office of Naval Research
PR Number: 00PR00602-00
Award Number: N0001400WR20023
Current End Date: 30-Sep-2000
Scientific Officer: Edward Kennedy

Objective:
To devise theoretical models and appropriate software capable of
determining how improvements can be made to current or future techniques for generating ELF through VLF frequencies through active interaction of high power HF radio waves with plasma at ionospheric heights. Successful development of this technique will afford alternative means for gener-ating signals useful for submarine communications and for geophysical probing.
Approach:
The absorption of HF energy in the D and E regions of the ionosphere will be calculated as a function of the HF frequency and electron density profile. The induced modification of the ionospheric conductivity will be determined. The three dimensional perturbation of
the electrojet current will be calculated for a selection of onospheric
conditions corresponding to real experimental situations. Software
models developed will allow evaluation of various efficiency enhancement schemes including beam painting and rapid pulsing. Results and products will be in a form that may be used for experimental verification at active ionospheric research facilities.
Progress:
Significant progress has been made this year in research to model
the generation of ELF/VLF waves by HF heaters. This work has been
published (Rowland, Journal of Geophys. Res.,104, 4319, 1999) and
presented at the Ionospheric Workshop 1999 in Santa Fe. Examples of
our 3D simulations are shown on our web page at wwwppd.nrl.navy.mil
under whatsnew-Haarp simulations.

Title: SINGLE ELECTRON CAPACITANCE SPECTROSCOPY
PI: Raymond Ashoori
MASSACHUSETTS INSTITUTE OF TECHNOLOGY
Department of Physics 13-2053
Address: RM E19 702 77 MASSACHUSETTS AVE
CAMBRIDGE, MA 02139
(617) 253-5585
Funding Agency: Office of Naval Research
PR Number: 00PR00613-00
Award Number: N000149310633
Current End Date: 30-Sep-2001
Scientific Officer: Larry Cooper

Objective:
To fabricate and develop the physical understanding of the nanometer scale semiconductor device structures which will be the devices used in future electronic systems. The focus will be on effects which are dominated by single electrons.
Approach:
The single electron capacitance spectroscopy technique will be used
to study a variety of single electron effects in semiconductor nano-structures. Few electron systems will be studied along with charging of single defects and single impurities in such structures. High resolution studies of quantum Hall systems at interfaces will be studied as well as the spectroscopy of traps in quantum wells. Charging of quantum dots and coupled quantum dots will be studied using the subsurface charge accumulation technique. Dangling bond states at the Si/SiO(2) interface will also be investigated using the SECS technique. The investigator will further develop the time resolved capacitance technique and apply it to several tunneling problems.
Progress:
A single electron transistor has been integrated on top of a quantum
dot in which the number of electrons moving off and on the dot can be
controlled one by one. The SET acts as an extremely sensitive electro-meter which senses the charge in motion in buried structures beneath the SET. This method has the potential to study charge motion in defects and impurities in semiconductor heterostructures, buried beneath the SET.

Title: THEORY AND APPLICATIONS OF MICROSCOPIC
PROPERTIES OF SEMICONDUCTOR INTERFACES
PI: Milan Jaros
UNIVERSITY OF NEWCASTLE UPON TYNE
Research Services Unit
Address: 6 Kensington Terrace
NewcastleUponTyneNE1 7RU, TX
Funding Agency: Office of Naval Research
PR Number: 00PR00614-00
Award Number: N0001490J1644
Current End Date: 30-Nov-2000
Scientific Officer: Larry Cooper

Objective:
The design and analysis of novel electron and optical devices in semi-conductor microstructures requires sophisticated calculations. These calculations will be used to probe new concepts for nonlinear materials and explain experimental results.
Approach:
The investigator will continue to develop the pseudopotential
techniques for application to semiconductor microstructures.
Structures of interest include heterojunctions with Type II band offsets, disorder effects at interfaces, and systems of reduced dimensionality, such as quantum wires and boxes. Structures will be explored which predict enhanced optical nonlinearities in the infrared range of wavelengths. These tasks will be chosen in order to explain the complex optical spectra observed in these structures.
Progress:
Transport calculations have been carried out for electrons moving in
the plane of InAs/GaSb heterojunctions. The scattering lifetimes are
determined for a variety of interface imperfection models. A full
perturbed Hamiltonian is used in a T-matrix based scattering calculation. The results indicate clearly that Sb atoms on As sites at the interface have a much stronger scattering rate than for As on Sb sites. This indicates efforts should focus on eliminating such Sb defects in the growth of the materials. The estimated difference in rates is a factor of 30x. Consideration of larger defect islands was also made. In one case involving 49 Sb atoms, the lifetime reduction factor is over 1000.

Title: Monte Carlo Approach to Quantum Transport
in Mesoscopic Systems Based on Electron
Wigner Paths
PI: Carlo Jacoboni
INSTITUTO NAZIONALE DI FISICA DELLA
MATERIA
Address: Via Dell'Acciaio, 139
Genova Italy, TX 45553
(616) 958-6046
Funding Agency: Office of Naval Research
PR Number: 00PR00615-01
Award Number: N000149810777
Current End Date: 30-Jun-2003
Scientific Officer: Larry Cooper

Objective:
To develop a theoretical basis and a computer modeling code which can be used in the simulation of quantum effect nanoelectronic devices in support of electron device development programs.
Approach:
Based on previous work, the Wigner trajectory concept will be extended and developed for implementation using Monte Carlo methods. Phonon scattering will be included and consideration will be given to the issue of open contacts and the effects of the boundaries. The code will be optimized for efficient computer usage to include many scattering events.
Progress:
The mathematical formalism to implement quantum transport of electrons in open nanostructures has been completed and implemented in a numerical simulation code. Computer limitations allow for no more than 2 electron-phonon scattering events, which means that trajectories can be followed for about 100 femtoseconds. Computer optimization will be needed.

Title: DEFECT PROCESSES IN WIDE BANDGAP
SEMICONDUCTORS
PI: George Watkins
LEHIGH UNIVERSITY
Department of Physics
Address: 526 BRODHEAD AVENUE
BETHLEHEM, PA 18015
(610) 758-3961
Funding Agency: Office of Naval Research
PR Number: 00PR00616-00
Award Number: N000149410117
Current End Date: 31-Oct-2000
Scientific Officer: Larry Cooper

Objective:
To understand the role of defects and impurities in wide bandgap semi-conductors which control the conductivity and the degradation in devices.
Approach:
Various spectroscopic techniques will be applied to studies of impurities and defects in the wide bandgap II-VI and III-V semiconductor
materials. These will include EPR, DLTS,FTIR and ODMR. The issues
involved include doping efficiency, donor and acceptor identification,
role of native defects (induced by high energy electron beam irradiation
at low temperature) and various complex defects. Hydrogen will be implanted to examine the effects of complex defects associated with
hydrogen. In-situ electron irradiation at varible temperature will probe
the motion of induced defects such as vacancies and interstitials. These
will be correlated with optical characterization results. Emphasis will be placed on various GaN epitaxial materials, including the LEO materials, and on bulk AlN samples.
Progress:
It has been shown that the processing of GaN devices, such as
formation of dielectrics, plasma etching, wet etching, etc., results in the in-diffusion of hydrogen at low temperatures, which readily passivates acceptor impurities. The outdiffusion and hydrogen trapping-detrapping processes in much more complex in heterostructure samples. While post process annealing is used to activate p-type doping, experiments involving deuterium show that the H(2) is removed much more readily from the surface regions than from the deeper (bulk) regions. Significant removal of H(2) requires temperatures above 800 C. IR spectroscopy was used to probe hydrogen related defects by measuring local mode vibrational frequencies. By comparing these frequencies with theoretical predictions for various types of defect-hydrogen pairs, it is concluded that hydrogen couples to gallium vacancies and not to nitrogen vacancies in implanted samples.

Title: Developing Functionality in Quantum Dots
PI: Jonothan Bird
ARIZONA STATE UNIVERSITY
Dept of Electrical Engineering
Address: Box 871603
Tempe, AZ 852871603
(602) 965-7421
Funding Agency: Office of Naval Research
PR Number: 00PR00618-00
Award Number: N000149910326
Current End Date: 30-Apr-2002
Scientific Officer: Larry Cooper

Objective:
To devise various quantum dot and coupled quantum dot structures and to investigate the transport of electrons in such structures which could form the basis for future nanoelectronic devices and circuits.
Approach:
Quantum dot and coupled quantum dot devices will be fabricated on
semiconductor heterostructures and the transport of electrons into and
through such structures measured as a function of temperature, voltage
and magnetic field. The fundamental quantum effects of dephasing of
the electron wavefunction due to environmental effects will be explored.
Separately, an external electrode configuration will be used to effect a
nonlocal control of the resonant quantum states in the dots to study the
possibility of a transistor effect, by nonlocal controlled switching.
Progress:
A localization effect has been observed in open quantum dots formed in
the split gate structures on GaAs/AlGaAs heterojunctions. Low
temperature measurements of electron conductance through the dots as
a function of temperature and gate bias indicate that there is a
localization effect which causes an extra resistance. The authors
conclude that remnant disorder in the dot, with contributions from
random impurities and scattering from interface roughness features, are
causing the effect. Additionally, the gate voltage dependence indicates
that part of the increased resistance is attributed to backscattering
effects on electrons at the entrance and exit to the dot.

Title: EXTENSIONS AND APPLICATIONS OF MAGNETIC
RESONANCE FORCE MICROSCOPY
PI: Daniel Rugar
INTERNATIONAL BUSINESS MACHINE RESEARCH
LAB
Address: 650 Harry Road
San Jose, ca 951206099
(408) 927-2027
Funding Agency: Office of Naval Research
PR Number: 00PR00619-00
Award Number: N0001498C0070
Current End Date: 31-Mar-2000
Scientific Officer: Larry Cooper

Objective:
To develop a highly sensitive magnetic resonance force microscope
(MRFM) and demonstrate the capability of this tool to identify individual defects in electronic structures.
Approach:
Microcantilevers will be employed which have force sensitivities of 1
aN or better. Sharp ferromagnetic tips will be used with tip diameters of 50 nm or smaller, and the magnetic field gradients of these tips will be carefully measured using MRFM techniques. The MRFM will be operated at temperatures approaching 1 K. The enhanced MRFM will be used to detect single electron spins associated with defects in a silicon dioxide sample. The detection of individual defects in semiconductor structures will also be investigated.
Progress:
Microcantilevers made in silicon, silicon nitride and polysilicon have
been studied to determine the factors affecting the mechanical Q factors
of such structures, in preparation for their use in measuring small
forces in various atomic force microscopies. It has been found that Q
decreases as the thickness of the cantilever decreases. Measurements at
low pressures, 0.001 milliliter and below indicate that surface effects
can take place where contamination or oxidation of silicon can affect
the mechanical properties. Generally, there are surface mechanisms
which are a dominating factor in reducing Q, and so surface treatments must be considered for optimizing performance.

Title: ELECTRON TRANSPORT IN SEMICONDUCTOR
HETEROSTRUCTURES & IN MESOSCOPIC SYSTEMS
PI: Karl Hess
THE BOARD OF TRUSTEES OF THE UNIVERSITY
OF ILLINOIS AT URBANA CHAMPAIGN
Beckman Institute
Address: 109 Coble Hall
Champaign, IL 618206242
(217) 333-2186
Funding Agency: Office of Naval Research
PR Number: 00PR00621-00
Award Number: N000149810604
Current End Date: 30-Nov-2000
Scientific Officer: Larry Cooper

Objective:
To develop computer simulation methods to study the operation of
quantum based lasers and electron transport devices. Physical
mechanisms which influence the performance limitations of both
optoelectronic and electronic devices will be illuminated.
Approach:
Semiclassical and quantum transport theory methods will be developed for investigation of electronic transport phenomena and problems related to the collection of charge in quantum wells, wires and dots under lasing conditions. Particular attention is directed toward the effects of phonons in these systems, as they influence the electron distributions and resultant gain processes. The limitations on modulation rates will be determined and alternate device concepts proposed. Hot electron degradation in silicon based, short channel FET structures will be studied in concert with deuterium substitution for hydrogen as the passivation species at Si/SiO(2) interfaces. Both high energy (6 eV) and low energy (<3 eV) electron processes will be investigated. The multi-electron vibrational mode excitation mechanism will be studied.
Progress:
MINILASE II, the laser simulation code has been extended so that it can
now accurately model Separate Confinement Heterostructure lasers, and their frequency modulation properties. This code bypasses the usual rate equation approach by calculating physics based simulations of both electron and hole transport consistently with solutions of the Helmholtz equation for the photons to determine carrier distributions in both space and time and to evaluate the gain functions throughout the device. Comparisons with available data for modulation of quantum well lasers is very good, and it is now possible to explore the various aspects of the device which determine its performance, i.e., limitations in modulation response, materials influence, etc. It can now be used as a design tool in a workstation environment.

Title: Research in Microstructure Electronics
PI: David Ferry
ARIZONA STATE UNIVERSITY
Electrical Engineering
Address: Box 871603
Tempe, AZ 852871603
(602) 965-2750
Funding Agency: Office of Naval Research
PR Number: 00PR00623-00
Award Number: N000149610110
Current End Date: 31-Oct-2001
Scientific Officer: Larry Cooper

Objective:
To develop theoretical and computer simulation methods to analyze the
physical performance of ultrasmall semiconductor devices and to
understand the nature of transport processes in nanometer scale
structures.
Approach:
Quantum transport theories will be developed which include short-time and non-equilibrium effects in nanometer scale semiconductor structures. Two particle and two time Green's functions analysis will be developed in order to deal with ultrasmall structures in which random spatial distributions of impurities are accounted for and in which all phase interference effects are included. Waveguiding effects and single
electron, or charge granularity, effects will be accounted for by
developing methods to deal with many body interactions in a realistic
fashion. The effects of the environment, contacts and material fluctuations will also be considered. Silicon and GaAs systems will be
addressed.
Progress:
As electron devices become smaller in dimensions, quantum effects become large and directly influence the design and operation of devices, or the devices are essentially quantum effect dominated. In addition, when such devices are close enough together, the question of quantum interactions between devices has to be answered. In order to describe and evaluate such effects in real devices, there must be formalism and simulation method which can address the question of where dissipation and deco-herence of electron wavefunctions occurs, i.e., in the contacts. A new approach to this problem has been formulated using non-Hermitian imaginary potentials in the form of time dependent density matrix tech-niques. This formalism allows for trapping and detrapping, and the decay of the wavefunctions in the region between the coherent region and the contact or decoherence region. It will now be possible to develop device simulation methods which correctly include the contacts. Decoherence and dissipation can now be taken into account in a realistic way.

Title: NOVEL DEVICES FOR NOVEL COMPUTATIONAL
PI: Thomas McGill
CALIFORNIA INSTITUTE OF TECHNOLOGY
Department of Applied Physics
Address: 1200 E. California Boulevard
Pasadena, CA 91125
(626) 395-4849
Funding Agency: Office of Naval Research
PR Number: 00PR00624-00
Award Number: N000149810567
Current End Date: 31-Mar-2001
Scientific Officer: Larry Cooper

Objective:
To explore semiconductor heterojunction materials and devices in
which quantum phenomena can be exploited in novel devices for
computation and signal processing.
Approach:
A variety of device structures will be fabricated based on hetero-junction materials made from InAs/AlSb/GaSb thin film semiconductors. These materials will explore novel device concepts such as, velocity modulated transistors, static random access memory, quantum dots, and spin transistors. Materials will be grown and characterized as appropriate. Device simulations as well as circuit simulations for incorporation of such quantum devices will be carried out.
Progress:
Modeling and simulation of tunneling devices is very difficult since it
involves a coupling of quantum transport effects with semiclassical
descriptions. The exploration of the Tunnel Switched Diode device for
possible applications as a Transistorless SRAM, as a photodetector,
chemical-sensitive switching and as an element of a neural network,
requires better understanding of its operation, and the effects of
different materials, layer thicknesses, doping effects, etc. The new
results on this project were determined by the development of a new
approach to the simulation problem, by coupling the Drift-Diffusion
method with Quantum Transmitting Boundary conditions. The method
has been applied to the tunneling problem in MOS structures and
correctly predict the transport properties and the development of
depletion and inversion layers. The case for the TSD is more difficult,
since the bistability is very sensitive to choices of carrier lifetime terms, layer thicknesses and the fact that both electron and hole tunneling have to be taken into account. However, it is shown that much of the operation of these devices can be described, although the values chosen for the material parameters is very critical if the bistable properties are to be explained.

Title: DEVELOPMENT OF GaN MOSFETS AND MISFETS
PI: Cammy Abernathy
UNIVERSITY OF FLORIDA
COLLEGE OF ENGINEERING
Address: 417 WEIL HALL
GAINESVILLE, FL 32611
(352) 392-0693
Funding Agency: Office of Naval Research
PR Number: 00PR00643-00
Award Number: N000149810204
Current End Date: 31-Dec-2000
Scientific Officer: John Zolper

Objective:
Study formation of insulating layers, including GdGaO and AlNV, on
SiC and GaN.
Approach:
Insulating materials will be deposited by MOMBE on SiC and GaN.
Structural and electrical properties will be characterized.
Progress:
The following was accomplished: 1) installation a gas-source molecular
beam epitaxy system for depostion of oxide dielectrics, 2) development of a pre-deposition cleaning procedure for reduced interfacial leakage, and 3) demonstration of the first GaN MOSFET. This depletion mode
MOSFET exhibited improved breakdown performance relative to Schottky devices and showed a unity current gain cut-off frequency of 3.1 GHz and a maximum oscillation frequency of 9.1 GHz at Vds = 25 V and Vg = - 20V.

Title: Theory of Surface Processes and Interface
Formation in Semiconductors
PI: Jerzy Bernholc
NORTH CAROLINA STATE UNIVERSITY
Dept. of Physics
Address: BOX 7514
RALEIGH, NC 276957514
(919) 737-3126
Funding Agency: Office of Naval Research
PR Number: 00PR00657-00
Award Number: N000149610161
Current End Date: 14-Dec-2001
Scientific Officer: Larry Cooper

Objective:
Theoretical modelling and computer simulation methods will be developed and applied to various problems in epitaxial growth of semiconductor films and interface formation.
Approach:
Theoretical methods including computer simulation techniques for
parallel supercomputing environments will be developed and applied to
various problems in surface processes and interface formation in semi-conductors. Problems of interest include: semiconductor growth mechanisms; passivation and etching; formation and electronic properties of heterojunctions. The GW approach will be developed which will be used to calculate the optical properties of the RDS response for various semiconductor surfaces. These will be used to evaluate the experimental results being obtained for in-situ characterization of various growing layers.
Progress:
Significant progress has been made in developing ab initio calculations
for describing Reflectance Difference Spectra for the MOCVD growth of
InP. Comparison of calculated optical reflectance spectra for the several postulated surface structures of the InP surface, for In-rich to P-rich conditions are in good qualitative agreement with measured spectra. The shapes and energies are unique for the atomic structures suggested. Whether In-In or P-P bonding arrangements or the In-P bonding
dominates can be determined, as the spectral signatures are unique.
Comparison with experiment is difficult since the surface may have a
mix of different structures, depending upon defects, temperature,
kinetic effects, etc. These results are an important step in the direction of eventually being able to observe in real-time and in-situ, the structure of a growing film.

Title: A THEORETICAL PROBE INTO THE ELECTRONIC,
GEOMETRIC, AND DYNAMICAL PROPERTIES OF
SEMICONDUCTORS
PI: John Joannopoulos
MASSACHUSETTS INSTITUTE OF TECHNOLOGY
Research Laboratory of Electronics
Address: 77 Massachusetts Avenue
Cambridge, MA 021394307
(617) 253-4806
Funding Agency: Office of Naval Research
PR Number: 00PR00658-00
Award Number: N000149710545
Current End Date: 30-Sep-2000
Scientific Officer: Larry Cooper

Objective:
To develop ab initio theory for studying heteoepitaxial films of
semiconductor materials which will produce improved substrate
materials for electronic devices.
Approach:
Ab initio theoretical techniques will be used to address the issue of
lattice matching in heteroepitaxial semiconductor systems. The
geometric structure and quasiparticle structure for interface systems will be calculated. Systematic studies of a new approach to forming
optimized mismatched systems will be made. The idea of creating a new
class of "pseudo" materials by choosing atoms from the II, III, IV and V
groups to simultaneously optimize both charge (in the bonds) and ion
size will be evaluated. Total energy optimization techniques will be used to find the best cases for growing III-V layers on Si substrates. One emphasis will be to formulate growth of a III-V alloy with direct optical gap at 1.5 microns.
Progress:
The growth of many semiconductor heterostructures is constrained by
the requirement of matching lattice constants, and in the case of
hetervalent systems, controlling the charge transfer across interfaces
which can lead to large internal electric fields. Using ab initio
calculation methods, a new approach has been proposed, in which the
effective bandgap of the material is constrained to a preset value at the same time as the lattice mismatch problem is minimized. This is an
example of computer design of materials. For the example of designing a
direct gap semiconductor grown lattice matched to Silicon with a
bandgap for use in the 1.55 micron optical devices, the interface layer
involves combinations of either group V and group II, or of group III and group VI. These are chosen to control the charge exchange. Elements
are chosen which have appropriate ionic radii. For the example chosen,
the lattice mismatch to silicon is 0.08%, thermal expansion mismatch is
zero at 350K and the bandgap is equivalent to a wavelength of 1.59
microns.

Title: WIDEBAND TRANSFERRED SUBSTRATE AlGaN-GaN
HETEROJUNCTION BIPOLAR TRANSISTORS FOR
MICROWAVE POWER APPLICATIONS
PI: Mark Rodwell
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA SANTA BARBARA
Department of Electrical and Computer
Engineering
Address: CHEADLE HALL ROOM 3227
Santa Barbara, CA 93106
(805) 893-3244
Funding Agency: Office of Naval Research
PR Number: 00PR00676-00
Award Number: N000149810061
Current End Date: 30-Sep-2000
Scientific Officer: John Zolper

Objective:
The Navy operates multiple radar systems on its vessels with carrier
frequencies in the 6-22 GHz range and with 100 - 1000 W per phased
array antenna desired. For this application, solid state-power amplifiers are desirable due to their reliabilitiy. The power amplifiers then must have high linearity and 6-22 GHz bandwidth. The proposed program addresses the development of high-power microwave transistors for this application.
Approach:
AlGaN microwave field effect transistors (FETs) with 50-100 GHz
f(max) and 100-200 V breakdown have been demonstrated. While AlGaN/GaN heterojunction bipolar transistors (HBTs) may compete with such FETs for 6-22 GHz power applications. The program will develop AlGaN/GaN HBTs with 50-200 V breakdown voltages and 100-500 GHz f(max). To this end, substrate transfer processes, low-resistance p-Ohmic contacts, and wafer fusion will be explored.
Progress:
During this period, the first AlGaN/GaN heterojunction bipolar
transistor was demonstrated. The structure was grown by MOCVD on a
sapphire substrate. Preliminary measurements showed a DC current
gain of 3. A Si doped (N-type) GaN sub-collector was followed by an
undoped collector and a Mg doped (P-type) base. The Si doped emitter
(n~ 5 x 10 18 /cm3) was grown with an Al0.1Ga0.9N barrier layer to
increase emitter injection efficiency into the strongly doped base. In an effort to reduce extrinsic base resistance associated with a high
p-contact resistance and high bulk resistivity, selective regrowth was
used to create a thick Mg doped pad for the base contacts. The additional extrinsic base thickness is intended to reduce bulk resistivity under the contact and repair damage caused by a chlorine dry etch. The common emitter IV characteristics suggested a high early voltage due to acceptor doping in the base of approximately 4 x 1019/ cm3. The present thrust is focused on fixing base contact problems, introducing a graded base for improved transit efficiency, and developing submicron emitter technology to be used with RF devices.

Title: High Resolution Transferred-Substrate HBT
Microwave / RF ADCs
PI: Mark Rodwell
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA SANTA BARBARA
Department of Electrical and Computer
Engineering
Address: CHEADLE HALL ROOM 3227
Santa Barbara, CA 93106
(805) 893-3244
Funding Agency: Office of Naval Research
PR Number: 00PR00683-00
Award Number: N000149810068
Current End Date: 14-Nov-2000
Scientific Officer: Max Yoder

Objective:
Seeks to exploit low parasitic heterojunction bipolar transistor
technology using a transferred substrate approach so as to obtain digital logic devices operating at 100 GHz that are capable of direct digital synthesis of signals as well as integral phase and frequency modulation.
Approach:
A transferred substrate approach will be used to create low parasitic
heterojuncion bipolar transistors wherein the base to collector parasitic capacitance is greatly reduced and in which these transistors will scale in two dimensions so as to operate at extremely low power.
Progress:
The low parasitic transferred substrate process has been developed from
the point of being a single-transistor process to the point where ICs of a few hundred transistors can be fabricated. Two generations of analog
ICs have been demonstrated in the process, including amplifiers of record 85 GHz bandwidth and record 360 GHz gain-bandwidth product. Extremely fast first-generation digital ICs (master-slave latches) have been demonstrated in the process with 48 GHz clock frequencies; 2:1 multiplexers and demultiplexers, W-band VCOs, and 30 GHz digital phase-lock-loops and are fabricated (but not yet tested). Designs for 100 GHz master-slave flip-flops have been completed and await fabrication. Initial design of 50 GHz adder-accumulators (for DDS) have been completed, and also await fabrication.

Title: BONDING DEFECTS AT SEMICONDUCTOR/INSULATOR
INTERFACES III
PI: Gerald Lucovsky
NORTH CAROLINA STATE UNIVERSITY
College of Physical & Math Sciences
Address: Box 8202
Raleigh, NC 276958202
(919) 515-3301
Funding Agency: Office of Naval Research
PR Number: 00PR00684-00
Award Number: N000149810562
Current End Date: 31-Mar-2001
Scientific Officer: Larry Cooper

Objective:
To develop technology and understanding of the formation of dielectric films on silicon with emphasis on the formation of interface bonds and related defect formation which affects nanoscale electron devices.
Approach:
Real-time linear and nonlinear optical characterization systems will
be built and applied to the study of various semiconductor/insulator
interfaces for in-situ growth studies. These will be carried out in
conjunction with experiments, modeling and theory to address interface
planarity, defects and defect precursors at the atomistic level. Silicon, GaN, AlGaN, and SiC will be among the systems under study. Insulators will include oxides, nitrides and oxynitrides.
Progress:
Using a variety of experimental techniques to probe the interface be-tween insulator films and silicon substrates, it is shown that enhanced performance for p-mos and n-mos transistors can be obtained when nitrogen is added to the processing. A 5 % monolayer addition to the first oxygen-silicon interface, followed by a thin SiO-2 film and a
final oxynitride film can reduce tunneling currents by factors up to a
hundred over normal thermal oxide insulators. These new insulators are
compatible with the remote plasma processing techniques developed by
the P.I., who has demonstrated that device quality insulators can be
prepared at ultra low processing temperatures of about 300 degrees centigrade rather than the usual thermal oxides formed at 1000 degrees
C.

Title: Development of a Superconducting
Semiconductor
PI: John Dow
ARIZONA STATE UNIVERSITY
Dept. of Physics & Astronomy
Address: ASB 210
Tempe, AZ 852871504
(602) 423-8540
Funding Agency: Office of Naval Research
PR Number: 00PR00690-03
Award Number: N000149410147
Current End Date: 30-Nov-2000
Scientific Officer: Larry Cooper
Objective:
To understand the atomic-scale phenomena involved in the interfacial formation of ferromagnetic metals on semiconductors and on high temperature superconductors and to determine their effects on spin injected electronics. The origin of superconductivity in the cuprate oxides will be studied.
Approach:
Low temperature STM measurments will be made on cleaved oxide super-conductor materials. Chemical and defect/impurity effects on the
nature of the superconducting properties will be studied. Theoretical
studies of the processes of spin polarized electrons interacting with
dimensionally confined magnon states in thin film metals on semicon-ductors will be made. In addition, spin flip scattering processes
at imperfect interfaces and with magnetic impurities in semiconductors
will be studied using first principle calculations of the materials.
Progress:
There is further evidence to indicate that the model for High Temperature Superconductivity in which the conductivity is due to
hypocharged oxygen and not the the cuprate planes. This model has
predicted superconductivity for several rare-earth substituted homologues of a variety of cuprate plane materials. The results indicate
that when magnetic ions are coupled with the cuprate planes, supercon-ductivity is not affected. Magnetic ions will cause Cooper pair breaking in the superconducting current. Thus, the planes are not the source of superconductivity. In the case of the PrBa(2)Cu(3)O(7), the usual theories indicate that this material is not a superconductor. However, there are now many experiments indicating that it does superconduct, if the Pr ion is not on the Ba site, which is the site nearest the hypo-charged chains.

Title: INNOVATIVE NANOTECHNOLOGY AND NANODEVICES
PI: Stephen Chou
THE TRUSTEES OF PRINCETON UNIVERSITY
Electrical Engineering Department
Address: E-Quad
Princeton, NJ 085445263
(612) 624-5599
Funding Agency: Office of Naval Research
PR Number: 00PR00693-00
Award Number: N000149810234
Current End Date: 30-Nov-2000
Scientific Officer: Larry Cooper
Objective:
To explore innovative nanofabrication technology and various nanoscale electron devices which can form the foundation of advanced electronic and optical systems.
Approach:
Novel nanofabrication technologies will be explored and developed
including nanoimprint lithography and various patterned substrate
approaches which includes self assembly aspects. Nanoelectronic
devices such as stacked quantum dot transistors and Aharonov-Bohm
ring transistors will be fabricated in silicon and their electronic
properties determined. The AB ring will be studied in terms of its
magnetic field sensitivity. Patterned substrates, using nanoimprint
lithography methods, will be used to explore formation of new materials.
This will be followed by studies which show intelligent or controlled
growth or self-assembly.
Progress:
Nanoimprint lithography techniques have been used to prepare a pattern of small mesas on a silicon surface. Subsequently, Ge atoms are deposited on the surface and allowed to migrate and self assemble into
quantum dot structures. AFM is used in-situ to characterize the size,
shape and position of the dots. The new result is that while lattice
mismatched strain (between silicon and germanium) causes the self
assembly, the mesa pattern controls the positioning of the dots. Further, the size and shape of the mesas controls the size and shape of the dots. This is an excellent demonstration of the patterning approach to controlling self-assembled quantum dots with contribution of Nano-imprint Lithography for positioning the dots. This is an important step toward developing quantum dot lasers and detectors, and perhaps a way to create circuits based on Quantum Dot Cellular Automata.

Title: CHARACTERIZATION OF MAGNETIC INTERFACES
PI: Yves Idzerda
NAVAL RESEARCH LABORATORY
Materials Science and Technology
Division
Address: NRL 6345
Washington, DC 203755320
(202) 767-3603
Funding Agency: Office of Naval Research
PR Number: 00PR00695-00
Award Number: N0001400WR20038
Current End Date: 30-Sep-2000
Scientific Officer: Larry Cooper
Objective:
To develop x-ray scattering based techniques for studying magnetic
materials and to apply them to the study of various magnetic multilayer
materials which are under consideration for new magnetoelectronic
applications.
Approach:
Circularly polarized soft x-rays from the Brookhaven synchrotron will
be used in the development of the X-Ray Magnetic Scattering method
and in XMCD, to investigate a variety of heteromagnetic materials.
Materials of interest include ferromagnetic films deposited on oxides,
semiconductors, colossal magneto-resistive materials, high temperature
superconducting materials, normal metals and other ferromagnetic
materials. Issues of interest are the nature of magnetic roughness at
interfaces, the correlation with chemical roughness or interdiffusion,
quantifying the correlation of domain structure between layers, and the
role of alloying between layers. These studies will be carried out in
coordination with other studies, elsewhere, on issues of spin transport,
spin tunneling and spin filtering effects in such materials.
Progress:
Using circularly polarized synchrotron radiation and spin polarized
photoelectron scattering techniques, the local order of magnetic
moments and the effects of thermal vibrations on such moments in thin
films of iron can be characterized. By measuring the temperature
dependence of the magnetic EXAFS signal and comparing the results
with theoretical analysis, it can be concluded that in addition to the
thermal vibrational effects there is the probability of magnetic
fluctuations affecting the local (atomic) magnetic moments of the iron
atoms which affect the scattering paths of the photoelectrons. This
technique has the potential for characterizing the local magnetic
structure in ferromagnetic metals and magnetic semiconductors.

Title: SPIN INJECTION & PROPAGATION IN HYBRID
MAGNETIC/SEMICONDUCTOR QUANTUM STRUCTURES
PI: Nitin Samarth
THE PENNSYLVANIA STATE UNIVERSITY
Department of Physics
Address: 110 TECHNOLOGY CENTER BUILDING
UNIVERSITY PARK, PA 168027000
(814) 863-0136
Funding Agency: Office of Naval Research
PR Number: 00PR00712-00
Award Number: N000149910071
Current End Date: 31-Oct-2001
Scientific Officer: Larry Cooper

Objective:
The fundamental processes associated with the injection and transport of spin polarized carriers in hybrid semiconductor/magnetic quantum structures will be explored and used to devise a novel and new class of devices for applications in nanoelectronics.
Approach:
Various heterojunction materials systems will be grown using II-VI
and III-V semiconductors in quantum well configurations; in addition,
magnetic components will be added by incorporating Mn ions into the
materials as well as the growth of ferromagnetic films on top of the
heterostructures. The injection of spin carriers by injection through
contacts or by optical pulse absorption will be attempted and the
transport in various fields will be studied. Picosecond pulse techniques
will be used along with NSOM technology. Spin FETs and RTDs will be
fabricated.
Progress:
Methods for growing quantum wells in modulation doped ZnTe/CdMnSe
materials have been developed. These thin film materials are shown to
have a high mobility 2 Dimensional Electron Gas. The inclusion of Mn
ions results in spin dependent transport phenomena, and in these
samples, there is little effect of the Mn ions on the 2DEG mobility. There are results to show that the magnetoresistance of the 2DEG can be
modulated by the external field.

Title: Superconducting RF Systems for Navy
Applications
PI: Anna Leese
SPACE AND NAVAL WARFARE SYSTEMS CENTER
SAN DIEGO
Code D721
Address: SPAWAR
(619) 553-2619
Funding Agency: Office of Naval Research
PR Number: 00PR00719-00
Award Number: N0001400WR20092
Current End Date: 30-Sep-2000
Scientific Officer: Deborah Van Vechten

Objective:
To continue the progress begun in fy99 toward demonstrating the
benefit of superconducting out of band rejection filters, both for existing FRPA GPS antennas (for potential near term insertion on AV8B and F18) and to protect the new Lm band from intentional jamming of the
C/A band. Determine whether Navy systems' needs, e.g., for a low Bit
Error Rate (BER) in digital communications links such as Link 16, and
for SIGINT functions can be significantly better served by
superconducting filters.
Approach:
The phase 1 program was so successful that Darpa has agreed to fund
an optimization of its cryocooler in fy00 with the goal of reducing the
heat load, weight and volume to the point where it is easy to insert it
between the FRPA antenna and the GPS EA-4 AEU and MAGR receiver, without lengthening the cool-down time of 2 filters to more than 30 min. Filter design methods will be sought to reduce differential group delay at band edges without degrading rejection possibilities. GPS JPO will be briefed on Darpa funded design of new Lm band filters and experimental results of testing phase 1 unit.

Title: Spin Injection & Propogation in Hybrid
Magnetic Semiconductor Quantum Structures
PI: David Awschalom
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA SANTA BARBARA
Address: Santa Barbara, CA 931065100
(805) 893-2121
Funding Agency: Office of Naval Research
PR Number: 00PR00738-00
Award Number: N000149910077
Current End Date: 31-Oct-2001
Scientific Officer: Larry Cooper
Objective:
To develop hybrid magnetic/semiconductor materials and device structures and to explore the physical processes of injection and transport of spin polarized carriers in such materials.
Approach:
Various semiconductor-magnetic metal and semiconductor-magnetic
semiconductor materials will be prepared and investigated using
transport and optical characterization techniques. The physics of spin
injection via low resistance contact or via optical injection will be
studied. Coherent spin propagation on nanosecond timescales will be
studied along with methods to control the drift of the carriers. Both
electric and gradient magnetic fields will be used. The materials will
include both II-VI and III-V semiconductors. Mn doped III-V nano-structures will be developed for use as spin injection contacts.
Progress:
Optical techniques have been used to probe the spin coherence in quantum structures based on ZnSe/ZnCdSe double quantum well films. Linearized pump-probe experiments of the spin coherence of the an injected spin polarized electron and hole distribution were made in both Faraday and Voigt geometries. The Faraday rotation of the propagating light oscillates in time. However, for the Faraday geometry the oscillations decay in a few picoseconds. For the Voigt geometry it takes 20 times longer. From this it is deduced that the holes, constrained by the geometry, are shown to spin scatter much more rapidly than the electrons. This means the electrons in the conduction band are free to
process independently for much longer times.

Title: HIGH SPEED LOGIC FOR ELECTRONIC BEAM
PI: Joseph Jensen
HUGHES AIRCRAFT COMPANY
Address: 3011 MALIBU CANYON ROAD
MALIBU, CA 90265
(310) 317-5250
Funding Agency: Office of Naval Research
PR Number: 00PR00746-00
Award Number: N0001498C0081
Current End Date: 27-Apr-2001
Scientific Officer: Max Yoder

Objective:
This work seeks to exploit low parasitic HBT technology to achieve a
direct digital synthesizer capable of synthesizing signals from audio
through X-band and modulating same with frequency or phase modulation.
Approach:
Low parasitic heterojunction bipolar transistors will be used to develop direct digital synthesizers.
Progress:
Simulations are being performed on the 4-to-1 mux for the delta-sigma DAC and the initial schematics of the 12-bit DAC design have been completed to the scaled lower parasitic process. The critical sub-circuits (e.g., Type D, master-slave flip-flop) have been demonstrated to operate at 70 GHz clock speed.

Title: Wideband Digital Delay Elements for True
Time Delay Beam Steering
PI: Kenneth Elliott
HRL LABORATORIES LLC
Address: 3011 Malibu Canyon Road
Malibu, CA 90265
(301) 317-5450
Funding Agency: Office of Naval Research
PR Number: 00PR00748-00
Award Number: N0001499C0159
Current End Date: 03-May-2002
Scientific Officer: Max Yoder

Objective:
Seeks digital means of providing differential intra-clock-pulse delay from zero to 7 nanoseconds with increments of 0.25 picoseconds in an
integrated circuit compatible with direct digitally synthesized signals for purposes of electromagnetic beam steering.
Approach:
Low parasitic heterojunction bipolar transistors will be used to design
low phase noise switched linear and non-linear differential delay lines
compatible for use in 100 GHz logic circuits.

Title: QUANTUM TRANSPORT AND ELECTRIC FIELD
DEPENDENT PROCESSES
PI: Gerald IAFRATE
UNIVERSITY OF NOTRE DAME
DEPARTMENT OF ELECTRICAL ENGINEERING
Address: UNIVERSITY OF NOTRE DAME
NOTRE DAME, in 46556
(219) 631-8673
Funding Agency: Office of Naval Research
PR Number: 00PR00758-00
Award Number: N000149910364
Current End Date: 31-Jan-2002
Scientific Officer: Larry Cooper

Objective:
To develop a theoretical formalism which can be used to describe the
phenomena of quantum transport effects in semiconductor nanostructures, in order to explain the performance of such nanoelectronic devices.
Approach:
A complete theory of Bloch oscillations will be developed and used to
study radiation output from such oscillations. This analysis will include the effects of elastic and inelastic scattering processes on dephasing and delocalization in nanostructures. The full density matrix will be used. Further, a detailed theory describing the influence of static and time dependent electric fields on threshold phenomena pertinent to the operation of nanoelectronic devices, i.e., optical absorption, Auger scattering, resonant tunneling, etc. will be developed. The nonlinear dependence of electric field strength will be investigated in tunneling through band engineered structures.
Progress:
Various problems of quantum transport have been set up in which the
Liouville equation for the one particle density matrix including time
dependent and homogeneous field conditions are included. A time
varying basis for the wave functions is used, so that Zener tunneling and memory effects can be properly accounted for. Multiband models for
semiconductors are being used to study Bloch dynamics in
multi-quantum well and superlattice device structures, such as Bloch
oscillators, QWIPs, etc.
Progress:
New start. No progress to report.

Title: Origins of Nonlinear Microwave Response of
HTS materials & Devices
PI: Ronald Ono
U S DEPARTMENT OF COMMERCE NATIONAL
INSTITUTE OF STANDARDS AND TECHNOLOGY
Cryoelectronic Metrology Group
Address: 325 Broadway
Boulder, CO 80303
(303) 497-3988
Funding Agency: Office of Naval Research
PR Number: 00PR00759-00
Award Number: N0001400F0007
Current End Date: 30-Sep-2002
Scientific Officer: Deborah Van Vechten

Objective:
To investigate the source of nonlinear behavior in HTS microwave films
and devices and improve the quality of commercially available state-of-the-art films. Non-linear behavior occurs in all HTS microwave devices, although isn't severe until power levels become significant-IP3 is above 40 dBm. Thus by determining the materials causes of the intermodulation distortion, how to optimize HTS filters for a wider range of practical applications -from today's low power, receive only filters to wide dynamic range filters of use in AMRFS- will be clearer. Moreover, methods of screening material before device fabrication can be de-veloped. This should lower costs, as well as improve performance,
of fielded high performance devices.
Approach:
The previously observed relationship between the geometry-independent figure of merit, the nonlinear scaling current density J0, and the nonlinear response of the patterned transmission lines will be further investigated and the correlations to the behavior of the microwave surface resistance and dc current dependent penetration depth explored. Different HTS film processes (such as ozone annealing), and different film growth methods will reveal the systematics of Jo and determine how to raise it a factor of 2 without degrading Rs. Most samples will come from collaborations with industry partners and other ONR-funded research groups, including the group investigating the effect of dynamic antifer-romagnetic stripes. The abilities to measure Rs(J, B) and harmonic pro-duction at low power levels will be improved.

Title: Characterization of the Inductive
Nonlinearity of Thin Oxide Superconducting
Films
PI: John Claassen
NAVAL RESEARCH LABORATORY
Code 6345 Materials Physics Branch
Funding Agency: Office of Naval Research
PR Number: 00PR00767-00
Award Number: N0001400WR20064
Current End Date: 30-Sep-2000
Scientific Officer: Deborah Van Vechten
Objective:
To prove the ability of low frequency magnetic penetration depth
measurements on unpatterned films to predict the intermodulation
distortion and IP3 of the same films, once patterned, at microwave
frequencies. This ability would provide a way of prescreening material
before the construction of microwave filters and a simple handle for
optimizing the material. Improved performance filters for use in Navy
Sigint receivers, and possibly multi-function systems such as AMRFS,
should result.
Approach:
To improve the existing magnetic penetration depth measurement system to remove a large thermal artifact. Measure samples provided by ONR supported PI. Collaborate with Drs. Ono and Booth of NIST, Boulder on developing the interpretation of the measurements.

Title: Novel Superconductor ADC Capable of
Operating in Interleave Mode
PI: Vasili SEMENOV
THE RESEARCH FOUNDATION OF THE STATE
UNIVERSITY OF NEW YORK AT STONY BROOK
DEPARTMENT OF PHYSICS AND ASTRONOMY
Address: STATE UNIVERSITY OF NEW YORK
STONY BROOK, NY 117943800
(516) 632-8931
Funding Agency: Office of Naval Research
PR Number: 00PR00770-00
Award Number: N000140010026
Current End Date: 30-Sep-2002
Scientific Officer: Deborah Van Vechten

Objective:
To demonstrate the benefit of separating the comparitor function and
the DAC function of a sigma delta class ADC by building a time interleaved ADC. Exceptional speed and accuracy will be obtained which
may allow direct reception at rf. Technologies to transfer signals
between chips will also be demonstrated, e.g., the signal will be
demultiplexed and the decimation function performed on a different
chip at a slower clock speed.
Approach:
Design, implement, and test and ADC based on a non-destructive
comparitor and separate phase generator. Time interleave at least 4
quantizer units and demux the data stream. Use a generic, separate
chip for a slower speed programmable decimation filter. Effective sample
rates in excess of 100 GSps are expected, especially in years 2 and 3
where finer lithography (1.5 micron and less) will be used and the basic
clock speed will be increased past 20 GHz.

Title: GaN Power Devices
PI: Steven Binari
NAVAL RESEARCH LABORATORY
Electronics Science and Technology
Division
Address: 4555 Overlook Avenue , S.W.
Washington, DC 203755320
(202) 767-2535
Funding Agency: Office of Naval Research
PR Number: 00PR00786-00
Award Number: N0001400WR20043
Current End Date: 30-Sep-2000
Scientific Officer: John Zolper
Objective:
To develop microwave devices and circuits based on wide bandgap refractory materials with emphasis on GaN and related AlGaIn/N
materials. The work is in-house at NRL.
Approach:
The effort shall focus on the design, fabrication, testing and
optimization of several highpower, microwave, discrete GaN devices.
These will include but not limited to MESFETs, HEMTs and HBTs. A
major output of the approach is the generation of a continuously
evolving S&T base for GaN and related materials which supports future
designs of these power devices which can transition to a product-oriented environment.
Progress:
A power density of 2.3 W/mm has been demonstrated at 3 GHz with a
AlGaN/GaN HEMT grown at NRL. Ungated drain currents up to 1 A/mm have been achieved. Detailed studies of trapping effects in AlGaN/GaN HEMTs have been performed using pulsed I/V characterization. Initial results suggest the traps are associated with the GaN buffer layer and not the surface or AlGaN barrier. Improvements in GaN HEMT materials and device design led to an fT of 52 GHz for a 0.2 um gate length. HEMT power performance was also improved. At 3.8 GHz, a power density of 2.9 W/mm with 30% PAE and 9.8 dB gain was measured for 150 um gate-width devices. At 9.5 GHz, 2.0 W/mm was obtained. The microwave power output was found to be correlated with the degree of gate lag.

Title: Computation as a Means of Understanding the
Operation of Future Devices
PI: Dragica Vasileska
ARIZONA STATE UNIVERSITY
Department of Electrical Engineering
Address: P. O. Box 875706
Tempe, AZ 852875706
(602) 965-6651
Funding Agency: Office of Naval Research
PR Number: 00PR00787-00
Award Number: N000149910318
Current End Date: 28-Feb-2002
Scientific Officer: Larry Cooper

Objective:
To develop computational methods to provide descriptive and predictive capability for semiconductor device performance.
Approach:
Computation methods will be extended and new advances incorporated for the modeling of ultrashort channel FET devices and of quantum dot structures. The effects of random numbers of impurities and their location in the channel will be determined using physics based models. Quantum effects due to confinement in narrow channels and quantum dots will be studied. New methods such as 2D and 3D Green' Function implementations will be developed to include the effects of intra-collisional field effects and interference phenomena associated with scattering from defects and impurities will be included in the codes. Monte Carlo models will be extended to 2Da nd 3D with full inclusion of electron-electron and electron-impurity interactions, also, with full band structure models to account for strain effects and other constraints.

Title: Equipment Expansion: Continuing Research on
Mechanisms & Control of Semiconductor
Growth & Deposition Experiment
PI: David Aspnes
NORTH CAROLINA STATE UNIVERSITY
Department of Physics
Address: Box 7514
Raleigh, NC 276958202
(919) 515-4261
Funding Agency: Office of Naval Research
PR Number: 00PR00788-01
Award Number: N000149310255
Current End Date: 31-Oct-2001
Scientific Officer: Larry Cooper

Objective:
To develop optical and analytic techniques for monitoring the atomic
scale processes of Organo-Metallic Chemical Vapor Deposition epitaxial
crystal growth.
Approach:
A dual purpose spectral-ellipsometer/reflection-difference-spectrometer will be used in the realtime, in situ investigation of heteroepitaxy of various heterojunction systems. Combined with closed loop control capability, the composition, strain and ordering of alloys will be monitored and controlled for OMCVD growth of these semiconductor systems. Correlating the RD spectra, which can be taken in real time, with light scattering experiments to measure surface/interface roughness, the optimiztion of film growth will monitor the onset of roughness and attempt to control or overcome such effects. A data base for RD spectra in alloys of the system InGaAsP will be determined. This material will be used as a vehicle to validate this system approach to controlled growth of semiconductors. A separate issue is that of strain determination in combination with interface chemistry and surface reconstruction. Efforts will be made to combine the measurements in a manner to allow control of the strain in the growth, as the film is growing.

Title: SPIN INJECTION AND TRANSPORT IN METAL /
SEMICONDUCTOR HETEROSTRUCTURES

PI: Berend Jonker
NAVAL RESEARCH LABORATORY
Materials Physics Branch
Address: ATTN CODE 3310
WASHINGTON, DC 203755320
(202) 404-8015
Funding Agency: Office of Naval Research
PR Number: 00PR00789-00
Award Number: N0001400WR20042
Current End Date: 30-Sep-2000
Scientific Officer: Larry Cooper

Objective:
Methods will be developed to form magnetic contacts to various semi-conductor materials and the effects of spin injected currents on the
optical and electronic properties of device structures will be studied for possible applications in optoelectronics and electronics.
Approach:
Magnetic material contacts will be formed on various semiconductors
including GaAs, ZnSe, ZnMnSe and Si. Contact materials will include
Fe, Co, MnGa and MnAl. Experiments in which spin polarized electrons
are injected into various semiconductor structures, such as quantum
well and 2DEG layers will be carried out to investigate the magnetic field effects on magneto-optical properties such as polarization, emission, and Faraday rotation. Spin lifetimes will be measured. Spin scattering at interfaces and spin diffusion lengths will be studied.

Title: Monolithically Integrated 1.3 um Emitting
Transceivers on GaAs Substrates
PI: P. Dapkus
UNIVERSITY OF SOUTHERN CALIFORNIA
Dept Contracts & Grants
Address: University Park
Los Angeles, CA 900891147
(213) 740-4414
Funding Agency: Office of Naval Research
PR Number: 00PR00790-00
Award Number: N000149910305
Current End Date: 28-Feb-2002
Scientific Officer: Yoon Park

Objective:
To develop monolithic transceivers operating at 1.3um for application to
ultrahigh bandwidth fiber optic data communications networks and analog RF systems. The proposed monolithic integration and the use of vertical cavity lasers in the transceivers will reduce system cost, increase bandwidth and improve reliability. Active regions for lasers and detectors on GaAs substrates that emit and detect light at 1.3 um will be developed and they will be incorporated with field effect transistors into monolithically integrated transcievers.
Approach:
The program will seek to develop new active region materials based on
quantum dots and novel heterostructures with oscillator strength at 1.3
um sufficient to support the operation of lasers and efficient detectors. These active regions will be incorporated into vertical cavity lasers and resonant cavity detectors and integrated with field effect transistors using the AlAs oxide integration technology. The integrated transcievers will be tested for application to digital and analog systems.

Title: Intensified Photo-Diode (IPD) Detector
Development
PI: V. Contarino
NAVAL AIR WARFARE CENTER AIRCRAFT
DIVISION
Code 4.5.5.6 EO Sensors Branch
Address: Naval Air Warfare Center
Patuxent River, md 206701161
(301) 342-2022
Funding Agency: Office of Naval Research
PR Number: 00PR00813-00
Award Number: N0001400WX20229
Current End Date: 30-Sep-2000
Scientific Officer: Yoon Park

Objective:
To extend lifetime and reduce signal induced noise in the IPD (Intensified Photo-Diode) detector.
Approach:
To increase the lifetime of the photo-cathode in pulsed LIDAR systems,
several methods will be devised to prevent the ions and X-rays from
getting back to the photocathode,thus preventing the damage and
afterpulse. Design a curved focusing path that would allow a fieldstop
to block both the ions and electrons. An electro-static focusing approach will be employed, and /or add a grid just behind the photocathode to reduce the energy a photoelectron would need to exit.

posted 06-07-2002 02:24 PM            

Title: Transport in GaN Materials & Devices
PI: Stephen Goodnick
ARIZONA STATE UNIVERSITY
Department of Electrical Engineering
Address: Box 875706
Tempe, AZ 852875706
(602) 965-3424
Funding Agency: Office of Naval Research
PR Number: 00PR00823-01
Award Number: N000149910385
Current End Date: 30-Apr-2002
Scientific Officer: Larry Cooper

Objective:
To measure the transport of electrons in GaN and AlGaN/GaN epitaxial
materials and to correlate these measurements with computer simulation models.
Approach:
High field and low field measurements of the transport of electrons
in GaN and GaAlN/GaN epitaxial films will be carried out using Schottky gated structures and microwave time of flight techniques. The goal is to obtain velocity-field curves for various materials and to correlate these properties with Monte Carlo simulations of transport in these materials. The effects of various inhomogeneities in the materials
will be studied, i.e. defects such as dislocations. Carrier relaxation
mechanisms will be investigated using fast pulse optical measurements.
Progress:
Low field velocity-field curves have been measured and will soon be
extended to the high field region. Full band Monte Carlo simulations
have been initiated. Electron-phonon interactions have been calculated
based on the calculated Density of States. A deformation potential has
been derived.

Title: QUANTUM CIRCUITS
PI: Robert Westervelt
THE PRESIDENT AND FELLOWS OF HARVARD
COLLEGE
Division of Applied Sciences
Address: Holyoke Center Room 440
Cambridge, MA 02138
(617) 495-3296
Funding Agency: Office of Naval Research
PR Number: 00PR00826-00
Award Number: N000149910347
Current End Date: 31-Jan-2002
Scientific Officer: Larry Cooper
Objective:
To investigate the behavior of coupled quantum devices and explore
their potential applications in ultra-low power circuit implementations.
Approach:
Quantum dot structures will be formed on semiconductor heterojunction materials with various gate control capability. Coupling between dots occurs either by quantum tunneling or by electromagnetic field inter-actions. Coulomb trap memory elements will be investigated. The coupled dots will be treated as basic elements of a quantum circuit which includes quantum phase coherence and entanglement for possible consideration in quantum computing. All devices will be fabricated with nanometer scale dimensions.
Progress:
Quantum tunneling has been studied in two coupled quantum dots. Electrostatic gates on the surface of a GaAs/AlGaAs heterostructure were used to create the dots. An adjustable quantum point contact between the dots allowed for variable coupling. In a high magnetic field the Quantum Hall Effect is observed with the transport occuring through edge states running around the edge of each dot. A new effect has not been explained, it is the observation that interdot energy is dependent upon the interdot conductance.

Title: Novel Approaches to the Study of Transport
in Nanometer-Scale Semiconductor Devices
PI: Fausto Rossi
INSTITUTO NAZIONALE DI FISICA DELLA
MATERIA
INFM - Dipartimento di Fisica
Address: Corso Duca degli Abruzzi 24
Funding Agency: Office of Naval Research
PR Number: 00PR00828-00
Award Number: N000149910462
Current End Date: 31-Dec-2000
Scientific Officer: Larry Cooper

Objective:
To develop Quantum Monte Carlo simulation methods which will be used to describe various nanoelectronic devices.
Approach:
This project has two tasks, one is to develop a Quantum Monte Carlo
approach to solve the quantum kinetic equations which represent open
quantum structures with both coherent and dissipative processes;
second, to calculate the electronic states of nanostructures, such as
silicon quantum dots, where the effectvie mass approximation breaks
down. In each case realistic band structure effects must be considered.
Thus, Tight Binding bandstructure calculations will be made for
inclusion in the transport modeling.
Progress:
In preparation for the transport calculations, a fully three
dimensional set of basis states has been derived. For the case of a one
dimensional quantum problem, such as for tunneling through a barrier,
the scattering states are defined, based on the transfer matrix method.
These are much more realistic than the use of plane waves and are more
natural when realistic boundary conditions are included. The boundary
conditions are critical and are currently being introduced within a
constant potential injection model.

Title: Microscopic Properties of Defects &
Interfaces in III-V Semiconcuctors with 6.1
A Lattice Constants
PI: Craig Taylor
UNIVERSITY OF UTAH
Office of Sponsored Programs
Address: 1471 FEDERAL WAY
SALT LAKE CITY, UT 84102
(801) 581-8751
Funding Agency: Office of Naval Research
PR Number: 00PR00829-00
Award Number: N000149910361
Current End Date: 28-Feb-2000
Scientific Officer: Larry Cooper

Objective:
To use a variety of optical spectroscopies to investigate the properties
of InAs/GaSb/AlSb heterojunction materials and to determine the effects of defects, impurities and interface inhomogeneities on such properties.
Approach:
Microscopic characterization of defects in bulk materials and at buried interfaces in InAs/GaSb/AlSb binary and ternary heterojunction materials will be made using a variety of optical spectroscopies, including Photo-luminescence, ODMR, FEL based internal photoemission (to obtain bandoffsets), etc. The strain in such heteroepitaxy materials will be determined using NMR techniques in collaboration with NRL scientists. Microwave Modulated PL will be used to measure surface recombination velocities at buried interfaces and correlated with the defect studies.
Progress:
Using the technique of microwave modulated Photoluminescence, the surface recombination velocity for InAs/GaSb heterojunction materials has been measured.

Title: Optical Studies of the Influence of
Microscopic Structure on the Optoelectronic
Properties of 6.1-Angstrom III-V Binary
Superlattices
PI: Thomas Hasenberg
UNIVERSITY OF IOWA
Divsion of Sponsored Programs
Address: 100 Gilmore Hall
Iowa City, IO 52242
(319) 335-1119
Funding Agency: Office of Naval Research
PR Number: 00PR00830-00
Award Number: N000149910379
Current End Date: 31-Jan-2000
Scientific Officer: Larry Cooper

Objective:
To grow semiconductor epitaxial films based on InAs/GaSb/AlSb
compounds and to investigate their properties using optical techniques
and provide information for optimizing these materials for device
applications.
Approach:
MBE will be used to grow a variety of two layer superlattice materials
in the 6.1 Angstrom family of semiconductors. Their structural properties will be measured to determine effects of strain and defects
at the interface. Carrier lifetimes and transport properties will be measured using optical techniques coupled with fast pulse injection.
Measurements will be made of recombination, transport and on spin
relaxation in superlattices. Theoretical support will provide band-structure information for the superlattice structures and models of
spin relaxation provided to help deduce the processes involved.
Progress:
Spin lifetimes for carriers in bulk GaAs and InAs as well as for
GaAs/AlGaAs and InGaAs/InP quantum wells using a 14 bulk band
wavefunction basis. The D'yakonov-Perel scattering mechanism is
considered for calculating the lifetimes. The theoretical results are in excellent agreement with the measured values.

Title: Nanoelectronic Circuit Technologies
PI: Richard Kiehl
UNIVERSITY OF MINNESOTA
Department of Electrical & Computer
Engineering
Address: 4-174 EE/CSCI Bldg
Minneapolis, MN 55455
Funding Agency: Office of Naval Research
PR Number: 00PR00837-00
Award Number: N000149910367
Current End Date: 31-Mar-2002
Scientific Officer: Larry Cooper

Objective:
To develop technology, devices and materials to support concepts of
nanoelectronic circuits based on single electron tunneling and its
application to high density, low power electronics.
Approach:
Analysis will be made of multiple valued Tunneling Phase Logic
circuitry and attempts to validate the concept in simple circuits to
implement a Residual Number System logic. The logic gates will be
formed in silicon using metal particles which form at sites controlled
by strain. Stressor patterns will be prepared and the self-assembly of metal dots will be investigated for various stressor geometries. Patterns in the form of Quantum Cellular Automata cells will be prepared.
Progress:
Progress has been made in determining the most useful operation
modes for single electron tunneling phase logic gates. A detailed
analysis has been made for how the mapping between the sum of the
input signals and the final output state of a multiple valued TPL gate
affects its functionality.

Title: Broadband Isolators for Multifunction
PI: Denis Webb
NAVAL RESEARCH LABORATORY
Code 6850
Address: 4555 Overlook Avenue
(202) 767-3312
Funding Agency: Office of Naval Research
PR Number: 00PR00909-00
Award Number: N0001400WR20059
Current End Date: 30-Sep-2000
Scientific Officer: John Zolper

Objective:
Develop simulation and testing capability for wideband circulator and
isolators.
Approach:
Simulation capabilities for circulators and isolators will be expanded to handle 6-port analysis, non-round geometries, and thermal
considerations. NRL will analyze simulation and design data from an
ONR contractor (EMA) who is developing circulators and isolators for
AMRFS. Small signal and high power testing of supplied components to
be performed.
Progress:
EMA's results for specific round circulators with radially-varying
properties were replicated using NRL's Green's function code. The
integral-equation method-of-moments code for treating the transmission-line isolator configuration has been tested and is now capable of analyzing microstrip circuits on simple magnetically biased gyrotropic material. Propagation constant vs. frequency examples have been run for the case of zero loss. The existing 2DFE code was modified to provide field plotting capability. Field plot results for a standard circulator were calculated, compared identically with the Green's function solver, and presented at the ONR AMRFS Workshop. Coding efforts were begun to generalize our existing 2DFE solver to allow for several enhancements needed to study new wideband circulator designs. The code is being rewritten to allow multiple and variable port locations, allowing employment of additional degrees of freedom in optimizing the wideband design of the isolator.

Title: Chemical Beam Epitaxy of High Quality GaN &
InGaN
PI: Phillip Cohen
UNIVERSITY OF MINNESOTA
Department of Electrical and Computer
Engineering
Address: 200 Union Street, S.E.
Minneapolis, MN 55455
(612) 625-5517
Funding Agency: Office of Naval Research
PR Number: 00PR00946-00
Award Number: N000149710063
Current End Date: 30-Sep-2002
Scientific Officer: Colin Wood

Objective:
To improve understanding of atomic scale processes of epitaxial
growth of Wide gap semiconductor epitaxial films.
Approach:
The proposed research will improve understanding and thence quality of epitaxial thin film crystal growth by use of a novel in situ scanning tunneling microscope at elevated temperatures.
Progress:
Quantitative surface structure measurements of GaN continue. PI
has reported the first observation of macrostep formation and layer-by-layer sublimation of GaN. These measurements were possible using a new octupole RHEED system and exceptionally smooth, epitaxial films grown on bulk GaN crystals obtained from Unipress (Poland). The quantitative electron diffraction data are now being compared to theory to obtain the atomic positions of surface atoms. Using atomic force microscopy 2-3 nm highmacrosteps were observed under low Ga fluxes. Large (1000 nm), atomically smooth hillocks were observed under excess Ga. These indicate the step edge barriers depend on NH3 flux and the diffusion of Ga over 1000 nm distances.

Title: Fundamental Limits to Small Scale
Magnetoresistive Memory and Sensors
PI: Peter Levy
NEW YORK UNIVERSITY
Department of Physics
Address: 15 WASHINGTON PLACE APT H-1
NEW YORK, NY 10003
(212) 998-7737
Funding Agency: Office of Naval Research
PR Number: 00PR00959-00
Award Number: N000149611207
Current End Date: 30-Nov-2001
Scientific Officer: Larry Cooper

Objective:
To investigate the effects of nanometer dimensions on the magnetic and magnetoelectronic properties of thin film magnetic materials and of magnetic device structures, and to establish a fundamental base of knowledge and understanding for advanced device development.
Approach:
Single magnetic metal films and multilayer films will be grown with
varying thicknesses; spin valve structures will be included. The effects of thickness on domain properties will be studied and correlated with
magnetostatic and magnetoelectronic properties. Arrays of such structures will be fabricated to study the effects of inter-device coupling. Nanofabrication methods will be applied to polycrystalline and single crystal metal multilayers and to magnetic tunnel junctions. This
includes electron beam lithography techniques in order to achieve
dimensions as small as tens of nanometers. Materials characterization
techniques will include Kerr microscopy, Near-Field Kerr microscopy,
Magnetic Force Microscopy, and Photoelectron Emission Microscopy.
Appropriate electron transport measurements will be made in correlation with the above characteristics. Theory will address the basic scattering mechanisms in these complex materials. Computer simulation of micro-magnetic models will be carried out to understand the magnetostatic properties of these structures and to explore the effects of inter-device coupling.
Progress:
The effects of shape and size of GMR film structures on the exchange
biasing effects have been studied in CoFe/IrMn and NiFe/IrMn elements produced by ion beam sputtering. Electron beam lithography and ion milling are used to produce regular arrays of submicron elements and transport structures. Magnetization processes have been probed using MOKE, MFM, and transport measurements.

Title: Studies of Deep Levels and Optimization of
MBE and MOCVD Grown GaN , AlGaN, and InGaN
for HEMTs
PI: James Speck
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA SANTA BARBARA
Materials Department
Address: Santa Barbara, CA 93106
(805) 893-8005
Funding Agency: Office of Naval Research
PR Number: 00PR00968-00
Award Number: N000140010063
Current End Date: 31-Dec-2002
Scientific Officer: John Zolper
Objective:
Optimize the growth and characterize deep level traps in GaN, InGaN,
and AlGaN for high electron mobility transistors.
Approach:
GaN, InGaN, and AlGaN will be grown by MBE and MOCVD for application to HEMTs. Detailed studies of trap density and energy levels will be carried out using controlled growth experiments in collaboration with Prof Ringel at Ohio State. InGaN growth will be further optimized for use as the channel in high power HEMTs.

Title: Investigations of Deep Levels & their
Physical Sources in GaN and Related Alloys
PI: Steven Ringel
OHIO STATE UNIVERSITY RESEARCH
FOUNDATION
Dept. of Electrical Engineering
Address: 2015 Neil Avenue
Columbus, OH 432101272
(614) 292-6904
Funding Agency: Office of Naval Research
PR Number: 00PR00970-00
Award Number: N000140010055
Current End Date: 31-Dec-2002
Scientific Officer: John Zolper

Objective:
Quantify traps in GaN, AlGaN, InGaN, and related materials grown
under various conditions.
Approach:
Deep level optical spectroscopy (DLOS), secondary ion mass spectroscopy (SIMS), electron beam induced current (EBIC), and Hall effect, among other techniques, will be used to study deep trap levels in the wide bandgap III-Nitride semiconductors. The studies will be closely coupled to controlled growth experiments at UCSB (Prof Speck and DenBaars) to correlate growth conditions and trap cross sections and concentration with device results.

Title: Third Workshop on Surfaces & Interfaces of
Mesoscopic Devices
PI: Karl Hess
THE BOARD OF TRUSTEES OF THE UNIVERSITY
OF ILLINOIS AT URBANA CHAMPAIGN
Beckman Institute
Address: 109 Coble Hall
Champaign, IL 618206242
(217) 333-2186
Funding Agency: Office of Naval Research
PR Number: 00PR01007-00
Award Number: N000140010059
Current End Date: 30-Nov-2000
Scientific Officer: Larry Cooper
Objective:
To provide a forum to discuss the latest advances and issues in the area
of mesoscopic devices and materials.
Approach:
A special workshop will be held in Maui, Hawaii on 13-17 December
1999 with invited speakers and contributed papers presented in the
areas of quantum dots, lithography for 10 nm devices, nanoscale
interconnects, single electron devices, quantum circuitry, STM
processing and nano-optics.

Title: Twenty-seventh Annual Conference on the
Physics and Chemistry of Semiconductor
Interfaces
PI: C. Schulte
INSTITUTE FOR POSTDOCTORAL STUDIES
Address: PO Box 10146
Scottsdale, AZ 852710146
(602) 423-8540
Funding Agency: Office of Naval Research
PR Number: 00PR01018-00
Award Number: N000140010058
Current End Date: 30-Sep-2000
Scientific Officer: Larry Cooper

Objective:
To organanize a conference and provide a forum to discuss the
advancements and issues involved in development of semiconductor
electronics.
Approach:
The 27th Annual Conference on the Physics and Chemistry of
Semiconductor Interfaces will be organized in Salt Lake City, Utah for
16-20 January 2000. Topics to be discussed include heterojunctions,
contacts, insulators, and a variety of materials such as silicon, III-V
semiconductors, and dilute magnetic semiconductors.

Title: JSEP FELLOWSHIP
PI: James Harris
THE BOARD OF TRUSTEES OF THE LELAND
STANFORD JUNIOR UNIVERSITY
Department of Electrical Engineering
Address: 125 Panama Street
Stanford, CA 943054125
(415) 723-9775
Funding Agency: Office of Naval Research
PR Number: 00PR01167-00
Award Number: N000149810107
Current End Date: 31-Oct-2000
Scientific Officer: Colin Wood

Objective:
The Fellow will examine the limits of micromachined tunnel devices
for feedback control of accurate micro-miniature MEMs positioners.
Approach:
Tunnel devices offer extreme sensitivty to applied pressure. These
will be studied for extremely fine manipulator feedback control.
Progress:
Kevin Gilbert completed his second year in the Ph.D. program in the
Department of Electrical Engineering. His coursework this year focuses
on areas of advanced semiconductor devices, processing and circuit
design. Kevin's coursework this year has continued to focus in the
areas of semiconductor devices and circuits. In the winter, Kevin passed the qualifying exams to enter candidacy in the doctoral program at Stanford. For his research into micromachined cantilevers, much of this year has been spent on finite element modeling of the electrical and mechanical response of the cantilevers. A mask set has been designed and built and he is currently working on developing the cantilever fabrication process.

Title: MICROSCOPIC STUDIES OF INTERFACES,
SURFACES, AND FILMS OF WIDE BANDGAP
MATERIALS USING BALLISTIC ELECTRON EMISSION
MICROSCOPY
PI: Jonathan Pelz
OHIO STATE UNIVERSITY RESEARCH
FOUNDATION
Department of Physics
Address: 1960 Kenny Road
Columbus, OH 432101063
(614) 292-8388
Funding Agency: Office of Naval Research
PR Number: 00PR01170-00
Award Number: N000149310607
Current End Date: 31-Oct-2000
Scientific Officer: Colin Wood
Objective:
To develop a new technique for inspecting the quality of buried
interfaces in metal/semiconductor and metal/insulator/semiconductor
structures with nanometer spatial resolution.
Approach:
Ballistic electron emission microscopy (BEEM) will be used to monitor
the conduction band structure in the base semiconductor, to
characterize the spatial variations of interface properties, to investigate hot-electron-induced interface modification, and to study the dependence of interface electronic properties on the atomic-scale
structure and chemistry of the interface, all with nanometer spatial
resolution. These techniques will be applied to the various polytypes of SiC and wide bandgap nitride semiconductors.
Progress:
The first BEEM measurements made on Pd/4H-SiC samples show two
distinct voltage thresholds. This indicates the existence of a
higher-lying conduction band minimum (CBM) which has never before
been seen experimentally. There is a recent theoretical prediction of
such a higher-lying CBM at approximately 0.11 to 0.13 eV above the
lowest CBM. The BEEM value is 0.14 eV. BEEM measurements on Pd
and Pt contacts on 6H-SiC indicate a single threshold and a spatial
uniformity of better than 0.03 eV, unlike the much wider spread seen in
conventional measurements. These measurements will be continued
and extended to other polytypes of SiC.

Title: A NEW APPROACH FOR FABRICATION AND
OPTOELECTRONIC INTEGRATION OF WIDE-BANDGAP
MATERIALS
PI: Mohamed-Ali Hasan
UNIVERSITY OF NORTH CAROLINA AT
CHARLOTTE
CC Cameron Applied Research Center
Address: Charlotte, NC 28223
(704) 510-6414
Funding Agency: Office of Naval Research
PR Number: 00PR01179-00
Award Number: N000149810572
Current End Date: 01-Apr-2001
Scientific Officer: Colin Wood
Objective:
To reduce cost and effort of producing large area (6" dia. ) GaN and SiC
semiconductor layer structures.
Approach:
Porous silicon will be used as a lateral epitaxial overgrowth (LEO)
template.
Progress:
A major investment was made on setting up and cleaning the
molecular beam epitaxy (MBE)/gas-source MBE (GS-MBE) facility for
the proposed work. For 3C-SiC carbide, the deposition was carried out
using two approaches. In the first, methane was used to convert porous
Si into SiC. This method resulted in partial conversion but the structure remained porous. FTIR showed clear but small SiC signal. While this structure is usable for devices such as gas detectors, radiation detectors, and solarcells, it is clearly useless for devices requiring planar and multilayer structures. In the second method, trimethylsilane was used. In this case, the top portion of the porous Si structure was converted and filled with the formation of a continuous overlayer of SiC on the structure. FTIR showed a strong and well defined SiC signal. Secondary ion mass-spectrometry (SIMS) results indicated a stoichiometric SiC with very low content of oxygen (as low as in the Si substrate-possibly the SIMS resolution limit) or other contamination. However, due to the high surface area of porous Si and its exposure to air prior to growth of SiC, the oxygen signal rose abruptly in the porous portion of the SIMS profile defining the boundaries of the underlying porous layer. At the same time the SIMS count rate of Si and C decreased gradually, as expected, with increasing depth in the porous layer. The gradual decrease indicates a filling and conversion of the top portion of the porous layer. Atomic force microscopy (AFM) showed large flatterraces separated by steep and high steps. Preparations for the growth of group III-nitrides are essentially complete. A RF atomic source with modified plasma zones as well as an effusion cell for Al were purchased and installed in the system. The capability for transmission electron microscopy (TEM) including sample preparation and a dark room for film/image processing were also completed.

Title: Nanostructured Wide Band Gap Semiconductors
PI: Wilson Ho
CORNELL UNIVERSITY
Department of Physics
Address: Clark Hall
Ithaca, NY 148532501
(607) 255-3555
Funding Agency: Office of Naval Research
PR Number: 00PR01180-00
Award Number: N000149910967
Current End Date: 30-Jun-2002
Scientific Officer: Colin Wood
Objective:
Investigate growth of high crystalline perfection GaN on Si.
Approach:
The reduced plastic flow temperature associated with nano-structured Si substrate surfaces will allow dislocations to be formed in the Si rather than in the much 'harder' GaN during epitaxial overgrowth.
Progress:
New start. No progress to report.

Title: MBE InN/InAlN HEMTs.
PI: William Schaff
CORNELL UNIVERSITY
Department of Electrical Engineering
Address: 415 Phillips Hall
Ithaca, NY 14853
(607) 255-3974
Funding Agency: Office of Naval Research
PR Number: 00PR01186-00
Award Number: N000149910936
Current End Date: 30-Jul-2002
Scientific Officer: Colin Wood

Objective:
To demonstrate superior power microwave performance from an InN based HEMT.
Approach:
Molecular Beam Epitaxy will be used to determine if low carrier
concentration InN and InAlN alloys with less than 5% Al can be deposited with good electrical (low background impurity) structural and optical properties. These will be processed into discrete high power microwave devices, and tested for DC to high frequency power microwave.

Title: MOCVD of InN/AlInN HEMTs
PI: Steven Denbaars
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA SANTA BARBARA
Materials Dept. College of Engineering
Address: Cheadle Hall, Room 3227
Santa Barbara, CA 93106
(805) 893-8511
Funding Agency: Office of Naval Research
PR Number: 00PR01187-00
Award Number: N000149910934
Current End Date: 31-Jul-2000
Scientific Officer: Colin Wood
Objective:
To investigate the use of indium nitride active layers for most efficient power microwave HEMTs.
Approach:
Indium nitride/aluminum indium nitride will be grown by MOVPE and
processed into high electron mobility 2DEG structure FETs.
Progress:
New start. No progress to report.

Title: Alternative Approaches to p-type Doping of
GaN
PI: Gary Wicks
UNIVERSITY OF ROCHESTER
The Institute of Optics
Address: Rochester, NY 14627
(716) 275-4867
Funding Agency: Office of Naval Research
PR Number: 00PR01190-00
Award Number: N000149611061
Current End Date: 30-Jul-2002
Scientific Officer: Colin Wood

Objective:
The PI seeks to prepare Boron Nitride and Phosphide cubic films for
UV detectors, emitters, and low electron affinity electron emitters.
Approach:
The proposer shall develop and employ an evaporation source for boron which is suitable, together with super heated nitrogen and, or ammonia for growth of BN by molecular beam epitaxy.
Progress:
The elemental boron effusion cell was used extensively this FY. The
solubility of B in GaN is found to be ~2% and that in AlN greater than
6%. The upper limit is yet to be determined. A crack-free nucleation
process for GaN on 3" Si was developed in conjunction with the BMDO
funded effort at RTI.

Title: GaN Piezoelectric Microwave Devices
PI: Michael Wojtowicz
TRW INCORPORATED SPACE AND TECHNOLOGY
DIVISION
Space and Electronics
Address: R6/2573 One Space Park
Redondo Beach, CA 90278
(310) 814-1713
Funding Agency: Office of Naval Research
PR Number: 00PR01192-00
Award Number: N000149830019
Current End Date: 25-Sep-2000
Scientific Officer: Colin Wood

Objective:
To demonstrate High power heterojunction bipolar transistors in nitride semiconductor films.
Approach:
Molecular beam epitaxy will be used to grow precisely defined epitaxial
group III nitride heterojunctions with built in strain fields in the c-plane of sapphire substrates. The strain field will cause a charge separation at the emitter base heterojunction. The assocated field will create the necessary 1e 14 cm-2 holes for low base resistance.
Progress:
Equipment and staff have been acquired for the program. Student at
GaTech identified and initial experimental growths and modeling
started.

Title: Wide Band Gap Bipolar & Heterojunction
Bipolar Transistors
PI: Michael Shur
RENSSELAER POLYTECHNIC INSTITUTE
Address: Thornton Hall
Charlottesville, VA 22903
(804) 942-4270
Funding Agency: Office of Naval Research
PR Number: 00PR01193-00
Award Number: N000149610682
Current End Date: 30-Sep-2000
Scientific Officer: John Zolper
Objective:
Seeks to better understand and exploit unique properties of
nitride-based semiconductor materials. Emphasis will be on new
transistor structures including HBTs and Induced Base Transistors.
Approach:
The large piezoelectric constants found in nitrides will be used to
model the effects on strain at interfaces. Dislocation density problems
currently encountered will be addressed to determine how they create
dipole fields within the lattice. Deformation tensors will be determined. Optimum designs for microwave transistors will be developed.
Progress:
New device concepts were developed based in polarization induced holes
for AlGaN/GaN HBTs. Initial studies of Induced Base Transistors (IBTs)
were developed for the AlGaN/GaN system and look promising as an all
n-type alternative to HBTs.

Title: SYNTHESIS OF SINGLE CRYSTALS OF GROUP III
NITRIDES IN SUPERCRITICAL AMMONIA
PI: Joseph Kolis
CLEMSON UNIVERSITY
Department of Chemistry
Address: Box 345702
Clemson, SC 296345702
(864) 656-4739
Funding Agency: Office of Naval Research
PR Number: 00PR01194-00
Award Number: N000149810834
Current End Date: 14-Aug-2001
Scientific Officer: Colin Wood

Objective:
The PI will develop a process for growth of GaN bulk crystals.
Approach:
Crystal boules will be crystalized from high temperature, high
pressure liquid ammonia solutions of GaN, using metal amides as
electrolyte solubilizers. This process is analogous to the hydrothermal process used for preparation of oscillator grade quartz.
Progress:
PI has made impressive headway in solubilizing GaN in high pressure ammonia solution at high pressures. He has been able to nucleate spontaneously GaN buk crystals on the order of 0.1 mm in dimension.

Title: Fabrication of AlGaN-GaN-InN High Electron
Mobility Transistors
PI: Umesh Mishra
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA SANTA BARBARA
Office of Research
Address: Rm 3227 Cheadle Hall
Santa Barbara, CA 931062050
(805) 893-4036
Funding Agency: Office of Naval Research
PR Number: 00PR01203-00
Award Number: N000149611024
Current End Date: 30-Sep-2002
Scientific Officer: Colin Wood

Objective:
The PI seeks to prepare films of GaN with radically reduced point and
extended defect densities.
Approach:
The PI will use lateral Molecular beam epitaxial overgrowth seeded
through etched holes in oxide films deposited on GaAs or similar
substrates.
Progress:
Lateral overgrowth on the order of 50 microns has been demonstrated. A growth system based upon Chloride vapor transport for more equilibrium and faster deposition has been constructed, and will be used to increase the lateral to vertical growth rate ratio. This will allow much larger islands of defect free GaN films.

Title: Investigation of Long Range Order in AlGaN
Films (Growth of GaN by Ionized Nitrogen
Cluster Beam Epitaxy)
PI: Theodore Moustakas
THE TRUSTEES OF BOSTON UNIVERSITY
College of Engineering
Address: 44 Cummington St, 4th Floor
Boston, MA 02215
(617) 353-5431
Funding Agency: Office of Naval Research
PR Number: 00PR01210-00
Award Number: N000149810213
Current End Date: 30-Sep-2002
Scientific Officer: Colin Wood

Objective:
To investigate presence, occurance, and possible elimination of
polytype inclusions in hexagonal nitride semiconductors.
Approach:
Scanning probe techniques will be used on cross sections of MBE
films prepared under different nucleation and growth conditions.
Progress:
PI will divert much of the ordering effort to investigate the growth of
nitride semiconductors from elemental gallium and nitrogen cluster
beams with energy per molecule tuned from 1000 to 1 electron volt. In
this way enormous growth rates of high crystal perfection semiconductor
group III nitride epitaxial films, and possibly bulk substrates may be
possible. PI has found that ordering in the nitride alloy systems
GaN/AlN depends strongly upon the growth temperature, pressure and
growth rate. Ordering was found to reduce the band gap narrowing up
to 500meV. Photo conductive detectors fabricated from these partially
ordered alloys had gains several orders of magnitude higher than
detectors fabricated on pure GaN films. Monte Carlo simulations are
used to describe the mechanism of ordering in the absorption-limited
growth regime.

Title: LOCALIZED ELECTRONIC STATES AT GaN
HETEROJUNCTION INTERFACES
PI: Leonard Brillson
OHIO STATE UNIVERSITY RESEARCH
FOUNDATION
Joseph C. Wilson Center of Technology
Address: 800 PHILLIPS ROAD W114
WEBSTER, NY 14580
(716) 422-6468
Funding Agency: Office of Naval Research
PR Number: 00PR01211-00
Award Number: N000140010042
Current End Date: 30-Sep-2002
Scientific Officer: Colin Wood

Objective:
To understand depth distribution of defects in Nitride power
semiconductor epitaxial films.
Approach:
High spatial and energy resolution cathodoluminescence inside
scanning electron (transmission) microscope.

Title: Nanolithographically Controlled Nucleation
of GaN and Growth of InGaN Quantum Dots on
Foreign and Compliant Substrates
PI: P. Dapkus
UNIVERSITY OF SOUTHERN CALIFORNIA
Dept Contracts & Grants
Address: University Park
Los Angeles, CA 900891147
(213) 740-4414
Funding Agency: Office of Naval Research
PR Number: 00PR01276-00
Award Number: N000149810598
Current End Date: 30-Oct-2001
Scientific Officer: Colin Wood

Objective:
PI will optimize the crystal perfection of GaN and AlN epitaxial films
for microwave and opto-electronic applications.
Approach:
PI will determine the optimum growth parameters for Lateral
Epitaxial Overgrown by modeling and metal organic chemical vapor
phase epitaxial growth on nanolithographically patterned substrates.
Progress:
Low defect GaN has been grown by epitaxial lateral overgrowth on
sapphire and Si/AlOx substrates. Pyramidal faceted overgrowths merge
without defects at the interface. The reactor has been modified to allow
the facet angle to be closed after merging. Current efforts are devoted to reducing the size of ELO openings to submicron dimensions by e-beam
and block copolymer lithography.

posted 06-07-2002 02:26 PM            

Objective:
To design and fabricate transmitters for application in very high speed
small signal and large signal optical communication systems. Lasers
based on InP/InGaAsP technology will be integrated monolithically with
modulators to provide high speed, low chirp modulation. A novel scheme using a multi-laser gain-switched system will be demonstrated to produce large signal optical modulation. Finally, designs for long-wavelength microcavity lasers for very low threshold output will be studied.
Approach:
Programs are geared to providing high speed light emission and
modulation. Device design and fabrication will be carried out to use
state-of-the-art growth and processing to achieve a laser-driver chip for internal modulation of lasers. An OEIC is designed to couple
monolithically a laser with a Starke effect external modulator.
Integration of up to 10 gain-switched lasers will be carried out to
produce large signal modulation of lasers. The architecture will produce up to 40 Gbps signals.

Title: A Proposal for the Organization of the
Sixth Workshop on Wide Bandgap Nitrides
PI: Hadis Morkoc
VIRGINIA COMMONWEALTH UNIVERSITY
Dept. of Electrical Engineering &
Physics
Address: 601 West Main Street
Richmond, VA 23284
(217) 333-0722
Funding Agency: Office of Naval Research
PR Number: 00PR01409-00
Award Number: N000140010062
Current End Date: 31-Dec-2000
Scientific Officer: Yoon Park

Objective:
To bring together experts from over the world to address issues and
determine where group III-nitride materials and device technology is
moving. Specific goals to identify problems facing III-nitirde technology and make recommendations on promising routes for resolution.
Approach:
In this meeting scientists and engineers from all over the world will
discuss the broad subjects coverng technology of III-Nitrides.

Title: International Workshop on ZnO
PI: David Look
WRIGHT STATE UNIVERSITY
Physics
Address: Office of Grants & Contracts
Dayton, OH 45435
(937) 255-1725
Funding Agency: Office of Naval Research
PR Number: 00PR01417-00
Award Number: N000149911054
Current End Date: 30-Sep-2000
Scientific Officer: Yoon Park
Objective:
To assess the state of the art in ZnO bulk and epitaxial materials and
the future possibilities of producing superior electronic and photonic
frm these materials.
Approach:
Approximately 50-75 participants from the USA and several foreign
countries are expected to attend to discuss the state of the art in ZnO
materials and devices.
Progress:
New start. No progress to report.

Title: All-fiber Integral High Speed Modulator &
Source for Compact, Lightweight,
Electro-Optic Systems
PI: Kerry Vahala
CALIFORNIA INSTITUTE OF TECHNOLOGY
Dept. of Appied Physics
Address: MAIL STOP 213-6
PASADENA, CA 91125
(818) 395-2144
Funding Agency: Office of Naval Research
PR Number: 00PR01420-00
Award Number: N000140010072
Current End Date: 30-Sep-2002
Scientific Officer: Yoon Park

Objective:
To demonstrate a multi-length addressable all-fiber modulator based on
control of critical coupling and integrate this device with fiber DFB
lasers to create all-fiber multi-wavelength source consisting of a single strand of optical fiber.
Approach:
Employ highly efficient coupling to silica micro-sphere whispering
gallery modes using a single mode optical fiber in which a fiber optic
taper has been prepared. The taper is fabricated by heating a portion of the fiber in a flame while pulling the unheated fiber sections to either side of this portion in opposing directions to achieve a narrow neck (typically 5 microns). A glass micro-sphere (typically 200-300 microns in diameter) is then attached to the taper to achieve coupling to WGMs.

Title: Large Adaptive Two-Color IR Sensors
PI: L. Kozlowski
ROCKWELL SCIENCE CENTER LLC
Address: 1049 Camino Dos Rios
Thousand Oaks, CA 91360
(805) 373-4267
Funding Agency: Office of Naval Research
PR Number: 00PR01421-00
Award Number: N0001499C0227
Current End Date: 30-Apr-2002
Scientific Officer: Yoon Park

Objective:
To develop large, high performance two-color IR focal plane arrays at
lowest possible risk. This program will yield successive breakthroughs in the performance and size of two color FPAs by exploiting the latest
silicon multiplexer and HgCdT detector technologies.
Approach:
Based on the adaptive multiplexer development at 18 um pixel pitch in
0.25um CMOS, an adaptive 1024x640 two-color FPA at 25um pixel pitch
will be developed and a 1280 x1024 array will be designed.

Title: Symposium J: Advanced Materials and
Techniques for Nanolithography
PI: Robert Pachavis
MATERIALS RESEARCH SOCIETY
Director of Finance
Address: 506 Keystone Drive
Warrendale, PA 15086
(724) 779-8313
Funding Agency: Office of Naval Research
PR Number: 00PR01588-00
Award Number: N000140010065
Current End Date: 30-Sep-2000
Scientific Officer: Larry Cooper
Objective:
To organize the Symposium on Advanced Materials and Techniques for
Nanolithography for the purpose of having open discussion on the latest
advances in the technology of fabricating nanoscale electron devices.
Approach:
The symposium will be held in conjunction with the Fall Meeting of
MRS in Boston, MA on 29 Nov to 3 December. Papers will be presented
to cover such topics as: advanced lithographies; advanced resists and
characterization; electron, ion and photon beam soft lithography; new
concepts in materials design; and nonconventional methods.

Title: 4 Gbit/in^2 Non-Volatile RAM
PI: K. Bussmann
NAVAL RESEARCH LABORATORY
NRL 6345
Funding Agency: Office of Naval Research
PR Number: 00PR01609-00
Award Number: N0001400WX20397
Current End Date: 30-Sep-2000
Scientific Officer: Ingham Mack

Objective:
Demonstrate an ultra high density non-volatile random access
memory test vehicle based upon vertical giant magneto resistance
memory elements and determine the ultimate limits in density and
operating speed for this technology.
Approach:
Utilize advancements in Si-based technology to realize high density
non-volatile memories compatible with Si processing. Memory
characteristics including transport parameters and switching
characterisitics using mininum feature sizes of 200nm, 100nm, and
75nm will be investigated.

Title: Retargeting LSI Rapid Single Flux Quantum
Circuits to a Sub-micron Fabrication
PI: Darren Brock
HYPRES INC
Address: 175 Clearbrook Rd
Elmsford, NY 10523
(914) 592-1190
Funding Agency: Office of Naval Research
PR Number: 00PR01712-00
Award Number: N0001400C0024
Current End Date: 30-Sep-2001
Scientific Officer: Deborah Van Vechten
Objective:
To make existing superconducting design methodologies compatible
with accepted semiconductor IC industry CAD file formats/design
artifacts, so as to be able to use these tools in designing
superconducting circuits, and increase the level of design automation.
At the same time, the new effects impacting ultra-compact physical
layouts with minimum geometries below 1 mm will be investigated and
the results incorporated into the design rules. These improvements will
facilitate the ability to develop full-function radio frequency integrated circuits operating at and above 100 GHz in military systems (radar, EW, comms) front ends.
Approach:
The benchmark digital speed circuit has run 10x faster (750 GHz) in
superconducting technology than in any semiconductor material and
>100x faster than silicon. The approach is thus to develop ways to utilize semiconductor CAD tools to design more general superconducting
circuits, incorporating the required sub-micron features and
non-linearities of Josephson devices. This requires reconstruction of
some of the tools designed specifically for superconductors to make the
design data set format consistent. Investigation of issues, especially
electromagnetic interactions among elements, that will become
important as circuit shrink is also planned.

Title: High Resolution STM Imaging & Spectroscopy
of Static Stripes in High Temperature
Superconductors
PI: James Davis
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA BERKELEY
Department of Physics
Address: 366 Le Conte Hall
Berkeley, CA 94720
(510) 642-4505
Funding Agency: Office of Naval Research
PR Number: 00PR01721-00
Award Number: N000140010066
Current End Date: 30-Sep-2000
Scientific Officer: Deborah Van Vechten

Objective:
To use a high spatial resolution STM to find experimental evidence of
static charge/spin stripes in a perovskite superconductor. Such stripes
have been hypothesized to be responsible for microwave loss by some
and, in dynamic form, as a fundamental causal mechanism for
superconductivity. If found, their characteristics should much more
severely constrain theories of HTS and allow their material nonlinear
characteristics to be improved. This will benefit Navy applications,
especially in high performance rf filters where currently the IMD limits
wide band applications.
Approach:
Use a high spatial resolution Scanning Tunneling Microscope to look for
static stripes in oxygen under doped YBCO, Zn doped BSCCO, and Nd-doped LSCO at concentrations where other measurements have suggested they should occur. Spatially periodic fluctuations in the energy gap and amplitude of the coherence peak will be sought. STM is an ideal tool given its ability to image topography on atomic scale, measure the local density of states at any given point, and map the density at a specific energy across the surface. Samples will be prepared by low temperature cleaving in the STM instrument.

Title: Optical Electronic & Optoelectronic
Material & Device Research
PI: A. Yariv
CALIFORNIA INSTITUTE OF TECHNOLOGY
Department of Electrical Eng and
Applied Physics
Address: Mail Stop 213-6
Pasadena, CA 91125
(818) 405-0928
Funding Agency: Office of Naval Research
PR Number: 00PR01841-00
Award Number: N000140010104
Current End Date: 31-Oct-2002
Scientific Officer: Yoon Park

Objective:
To conduct promising research in terms of basic importance and
potential applications, and, in large part, a new and largely innovative
set of projects which are both conceptually and technologically in the
forefront of today's optical communication research.
Approach:
Selected research areas of both theoretical and practical importance will be pursued. Areas include mode-locked lasers for high-speed A/D
sampling, amplitude-phase correlation effects in semiconductor lasers
and their effect on signal and noise propagation in fiber, high-order
polarization mode dispersion and its control, and mode conversion
phenomenon and devices based on optical gratings in fibers.

Title: Study of Replacement of Surface Navy Tube
Transmitters with Solid State Alternatives
PI: Joe Smolko
RAYTHEON COMPANY
Address: P.O. Box 1201
Tewksbury, MA 018764169
(978) 858-4169
Funding Agency: Office of Naval Research
PR Number: 00PR01906-00
Award Number: N0001400M0004
Current End Date: 23-Dec-1999
Scientific Officer: John Zolper

Objective:
Determine the potential for replacement of vacuum tube transmitters
with solid state alternatives in surface Navy systems.
Approach:
A study will be performed to access the potential improvement in system
performance, reduced maintainance, and cost for replacing vacuum
tube transmitters with solid state alternative in surface Navy systems.

Title: Solid State Transmitter Replacement Study
for SPY-1 adn MK-99 Transmitters
PI: Mahesh Kumar
LOCKHEED MARTIN GOVERNMENT ELECTRONIC
SYSTEMS
Government Electronic Systems
Address: 199 Borton Landing Rd
Moorestown, NJ 080570927
Funding Agency: Office of Naval Research
PR Number: 00PR01907-03
Award Number: N0001400M0006
Current End Date: 31-Mar-2000
Scientific Officer: John Zolper

Objective:
Perform a study to determine the potential for replacing vacuum tube
transmitters with solid state modules in SPY-1 and MK-99.
Approach:
A detailed trade study will be perfrom to quantifiy the potential for
replacing vaccum tube transmitters in 2 key Navy systems (SPY-1 and
MK-99).

Title: ACI program for the Lateral Epitaxial
Overgrowth of GaN on Si
PI: Ian FERGUSON
EMCORE CORPORATION
Address: SOMERSET, NJ 08873
(732) 271-9090
Funding Agency: Office of Naval Research
PR Number: 00PR01955-00
Award Number: N0001499C0337
Current End Date: 30-Dec-2001
Scientific Officer: Colin Wood

Objective:
To create a viable industrial supply of inexpensive semiconductor GaN
films.
Approach:
Films will be grown by metal organic vapor phase deposition on Si
substrates using the technology developed at UC Santa Barbara under
phase 1 of this ACI program, under the AMRFS umbrella.

Title: Characterization of Local Electronic
Properties in Nitride Semiconductors
PI: Edward Yu
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA SAN DIEGO 0934
Electrical & Computer Engineering
Address: 9500 Gilman Drive
La Jolla, CA 920930407
(619) 534-6619
Funding Agency: Office of Naval Research
PR Number: 00PR02043-00
Award Number: N000140010135
Current End Date: 30-Sep-2001
Scientific Officer: Colin Wood

Objective:
To determine the defect density distribution and electrical (energy level) characteristics in GaN emiconductors.
Approach:
A scanning capacitance probe will be used to measure local surface
electric fields associated with dislocations and point defects.

Title: A Plan to Verify and Determine the Source
of Intense Heater Induced ELF and VLF
Signals in the Ionosphere
PI: Michael Kelley
CORNELL UNIVERSITY
Electrical Engineering
Address: Electrical Engineering Department
Ithaca, NY 14853
(607) 255-2944
Funding Agency: Office of Naval Research
PR Number: 00PR02138-00
Award Number: N000149910248
Current End Date: 30-Sep-2001
Scientific Officer: Edward Kennedy

Objective:
The Navy must maintain vital communiation links to fleet elements. The
submarine force uses frequencies in the ELF/VLF range to achieve
strategic connectivity. Existing communication transmitting facilities
require large spaces to support the necessary antenna installation. The
objective is to study a potentially new approach for generation of
ELF/VLF communication signals through ionospheric modification. If
successful, improvements in physical assets and annual operating cost
may be possible.
Approach:
ELF/VLF generation experiments are regularly conducted at several
active ionospheric modification research facilities in the US and
elsewhere. Known techniques for signal generation are currently less
than sufficient to be competitive on a technical performance basis with
the existing Naval installations (although there are proposed theoretical techniques for improving on this). The work in this effort will determine if data previously acquired under a cooperative experiment may indicate a new, unidentified mechanism for ionospherically generated ELF/VLF, and, if so, develop a theory that can be evaluated and proven experimentally under controlled conditions.
Progress:
Rocket data from the Coqui Dos campaign at Arecibo continues to be evaluated. There is strong evidence that ELF fluctuations were created by amplitude modulation of the heater beam. Recent efforts have led to a scheme for demodulation of the HF signal detected on the rocket below the reflection point. It is very clear that an ELF component (below 20 Hz) is present in the demodulated data. The current effort is to compare this to the simultaneous ELF signal directly measured by the electric field receivers. The AM modulation was recorded using a heterodyned system and the magnetic field signal from a search coil. Results of this work will be published during the next year.Additional experiments are being designed to reproduce these results. A prototype experiment was performed in August 1999 using the FAST satellite. Working with Dr. Zwi at the HAARP site and Dr. Carlson of U.C. Berkeley, the HAARP heater was modulated at ELF during two passes of FAST below 1500 km. The data from that experiment are currently being analyzed.

Title: Linear Wide Band Vacuum Electronic Power
Amplifier
PI: Phil Ballagh
LITTON SYSTEMS INC
Electron Devices Division
Address: 960 Industrial Rd
San Carlos, CA 940704194
(650) 591-2513
Funding Agency: Office of Naval Research
PR Number: 00PR02271-00
Award Number: N000140030017
Current End Date: 14-Apr-2001
Scientific Officer: Ingham Mack

Objective:
Develop a linear, wideband booster TWT that with only modest modifi-cations to electrical design parameters and/or operating voltages
and currents, that can be used in ECM, radar, and communication
applications.
Approach:
Modeling and simulation tools will be employed with prototype tubes
built, tested, and fully characterized. External linearization methods
will be studied and incorporated as necessary.

Title: Development & Validation of Multi-Frequency
Design Codes for Linear High Power
PI: David Chernin
SCIENCE APPLICATIONS INTERNATIONAL CORP
P.O. Box 1303
Address: 10260 Campus Point Drive
San Diego, CA 92121
(703) 734-5808
Funding Agency: Office of Naval Research
PR Number: 00PR02274-00
Award Number: N000140020006
Current End Date: 30-Sep-2002
Scientific Officer: Baruch Levush

Objective:
Develop simulation technology for traveling wave tubes and
klystrons.
Approach:
Extend 1D simulation codes to 2D for TWT's and klystrons and
validate codes by comparison with experiment.

Title: To Organize the ONR Superconducting
Electronics Program Review and Conference
PI: S. Sridhar
NORTHEASTERN UNIVERSITY
Distinguished Professor of Physics
Address: Physics Dept.
Boston,, MA 02115
(617) 373-2930
Funding Agency: Office of Naval Research
PR Number: 00PR02401-00
Award Number: N000140010118
Current End Date: 15-Apr-2000
Scientific Officer: Deborah Van Vechten

Objective:
To organize logistics for the program review of the ONR
superconducting electronics program, including the invitational
workshop on antiferromagnetic stripes in mixed valance oxides. The
program review helps to unify the PIs and allow more facile coordination
of their efforts in behalf of the Navy. Both 6.1 and 6.2 program PIs
attend.
Approach:
To support the conference through deposits that are required by the
hotel and help with administrative costs. To cover travel costs for 8
people not currently supported by ONR who will be invited to speak.

Title: 100 GHz DUAL CHANNEL PM/AM NOISE
MEASUREMENT SYSTEM
PI: Fred Walls
U S DEPARTMENT OF COMMERCE NATIONAL
INSTITUTE OF STANDARDS AND TECHNOLOGY
NIST 847.30
Address: 325 Broadway
(303) 497-3207
Funding Agency: Office of Naval Research
PR Number: 00PR02417-00
Award Number: N0001499F0373
Current End Date: 30-Jun-2000
Scientific Officer: Deborah Van Vechten

Objective:
This award will allow the time and frequency (standards) division of NIST to establish a first in the nation phase and amplitude noise
measurement system in the frequency range 75-110 GHz. Such measurements are needed to determine the relative noise performance of candidate digital signal processing technologies and both oscillators and amplifiers in this frequency range. Low noise performance is critical
to the performance of advanced rf systems such as AMRFS.
Approach:
The award will purchase equipment necessary to construct a dual
channel measurement system in which a cross-correlation spectrum
analyzer is used to reduce the noise level of the measurements by
averaging the independent results of the two channels. Calibration of
the system and initial measurements on 4 ONR selected 100 GHz
circuits are also included.
Progress:
The required pair of precision 10 GHz sources have been ordered and
will be delivered in Feb, 2000. The definition of the less critical
components has begun.

Title: PM/AM Noise Measurements in Support of 100
GHz Research
PI: Fred Walls
U S DEPARTMENT OF COMMERCE NATIONAL
INSTITUTE OF STANDARDS AND TECHNOLOGY

Address: 325 Broadway
(303) 497-3207
Funding Agency: Office of Naval Research
PR Number: 00PR02417-01
Award Number: N0001400F0415
Current End Date: 30-Sep-2002
Scientific Officer: Deborah Van Vechten

Objective:
This award will allow the time and frequency (standards) division of NIST to utilize the just established phase and amplitude noise measurement system in the frequency range 75-110 GHz to provide feedback on the success of components constructed for application in AMRFS systems. Such measurements will determine the relative noise performance of candidate digital signal processing technologies and both oscillators and amplifiers in this frequency range. NIST's expertise in these
measurements will also be passed to the industrial community via a
NIST sponsored workshop to be held in the summer of 2000 in Boulder
on phase and amplitude noise measurements.
Approach:
The renewal of this award will fund additional dual channel AM/PM
noise measurements with reduced noise level via cross-correlation
averaging the independent results of the two spectrum analyzer
channels. In addition, a workshop on noise measurement techniques
will be held at NIST in summer of FY00. Vendors of the AMRFS program
will receive consulting advice on phase noise if there is a demand for
such instead of for calibrations.
Progress:
The required pair of precision 10 GHz sources to build a 100 GHz
system have been delivered and how to construct the less critical
components has been determined. Measurement capacity should be in
place before the end of the base award in June 2000.

Title: Laser Annealing of Ferroelectric Thin Films
PI: James Horwitz
NAVAL RESEARCH LABORATORY
Interactions with Surfaces
Address: University of Rhode Island
Kingston, RI 028810801
Funding Agency: Office of Naval Research
PR Number: 00PR02499-00
Award Number: N0001400RC20016
Current End Date: 30-Sep-2000
Scientific Officer: Deborah Van Vechten

Objective:
Microwave loss in ferroelectrics has been shown to correlate to film
stress by NRL and oxygen vacancies are the presumed cause. Laser
annealing is known from the semiconductor industry to allow structural
defect annealing without long range dopant diffusion or interface
reactions. This award will help fund an effort to see if laser annealing in an oxygen environment will correct the oxygen deficiency or otherwise reduce the stress in ferroelectric thin films. Films are used in high performance rf filters to provide voltage controllable tuning of the filter characteristics.
Approach:
Collaborate with researchers at the Ashtarak (Armenia) Institute for
Physical Research to modify a laser patterning system developed in
FY98-99 to perform laser annealing in the IR. Use this system to attempt
laser annealing of ferroelectric thin films. Measure the changes in stress and microwave loss induced by the processing. Use these funds to cost share the non-U S expenses in a NICOP proposal on this topic.

Title: JOINT SERVICES GRADUATE FELLOWSHIP PROGRAM
PI: Jonathan Allen
MASSACHUSETTS INSTITUTE OF TECHNOLOGY
Research Laboratory
Address: RM E19 702 77 MASSACHUSETTS AVE
Cambridge, MA 021394307
(617) 253-2509
Funding Agency: Office of Naval Research
PR Number: 00PR02591-00
Award Number: N000149810039
Current End Date: 14-Oct-2000
Scientific Officer: Colin Wood
Objective:
To improve methods for generation and study of Bose Einstein
condensates.
Approach:
Experimental methodology will be tightened up by redesign of equipment for more uniform constraining magnetic fields, and freedom from vibration, faster cool down and better temperature control, etc.
Progress:
Research assistant Stamper Kurn has made extremely good progress
on Bose Einstein condensate research: specifically, he has observed a Freshbach resonance, which modifies resonance in Bose
Einstein condensates; he has created BE condensates above the BE
temperature by application of IR; and developed and demonstrated a new
kind of quantum fluid - a 3 componentspinor Bose condensate.

Title: Ohmic Contacts to P-Type SiC
PI: John Crofton
MURRAY STATE UNIVERSITY
Dept. of Physics & Engineering Physics
Funding Agency: Office of Naval Research
PR Number: 00PR02638-00
Award Number: N000149910785
Current End Date: 31-Aug-2000
Scientific Officer: John Zolper

Objective:
Develop low specific resistance ohmic contacts to p-SiC for bipolar
devices.
Approach:
The PI will study alloys of Al/Ti and Al/Si to develop ohmic contacts
to p-SiC with the low specific contact resistance reported for Al alone but with improved morphology and reduced spiking.
Progress:
We are looking at different Al to Ti ratios and the effect they have on
ohmic contacts to p-type SiC. In addition, the effect of introducing small amounts of Si is also being studied. Reducing the Al concentration in an Al-Ti alloy does not appear to hurt the contact's electrical properties. In addition, preliminary results indicate that the intro-duction of a few weight percent of Si to Al does not adversely affect the electrical properties of the contact. Further tests are underway to see if the reduction of Al and or the introduction of Si may help prevent the large degree of Al penetration into the SiC material.

Title: Workshop on Polarization Effects in
Semiconductors
PI: Shari Allwood
ALLWOOD AND ASSOCIATES INC
Address: 8279 Midland Rd
Mentor, OH 44060
(440) 951-1380
Funding Agency: Office of Naval Research
PR Number: 00PR02660-00
Award Number: N000140010134
Current End Date: 30-Nov-2000
Scientific Officer: Colin Wood

Objective:
Conduct a Meeting of world experts to challenge prolems of polarization
effects in power microwave devices for AMRFS.

Title: Microstructure & Electronic Properties of
InGaN Quantum Wells
PI: Fernando Ponce
ARIZONA STATE UNIVERSITY
Physics & Astronomy
Address: PO Box 871504
Tempe, AZ 852871504
(480) 727-6260
Funding Agency: Office of Naval Research
PR Number: 00PR02703-00
Award Number: N000140010133
Current End Date: 31-Dec-2000
Scientific Officer: Colin Wood

Objective:
To determine the charge state and density of threading dislocations in
nitride semiconductors.
Approach:
Electron beam holography in transmission electron microscope will
image and quantify charge centers in semiconductor thin films.

Title: ONR-312 Electronics Program Triennial
PI: Bette Treadwell
DANIEL EKE AND ASSOCIATES PC
Address: 818 Roeder Road, Suite 702
Silver Spring, MD 20910
(301) 589-6963
Funding Agency: Office of Naval Research
PR Number: 00PR03028-00
Award Number: N0001498D04180006
Current End Date: 31-Dec-1999
Scientific Officer: Max Yoder
Objective:
To provide logistic support and management services for Ocean
Atmosphere and Space Department internal reviews.
Approach:
Contractor will prepare and distribute information packets; maintain
and update appropriate mailing lists; arrange for audio-visual
equipment; and create and maintain event database and provide
administrative support on-site.

Title: ONR-312 Electronics Program Triennial
PI: Bette Treadwell
DANIEL EKE AND ASSOCIATES PC
Address: 818 Roeder Road, Suite 702
Silver Spring, MD 20910
(301) 589-6963
Funding Agency: Office of Naval Research
PR Number: 00PR03028-01
Award Number: N0001498D04180007
Current End Date: 31-Dec-1999
Scientific Officer: John Zolper

Objective:
To provide logistic support and management services for ONR 312,
Electronics, AMRFS 2000 Gathering.
Approach:
Contractor will prepare and distribute information packets; maintain
and update appropriate mailing lists; arrange for audio-visual
equipment; and create and maintain event database and provide
administrative support on-site, such as nametags, scoresheets and
folders for panel, and final report.

Title: Workshop on Next Generation MM-Wave Solid
State Power: Materials, Devices & Systems
PI: Shari Allwood
ALLWOOD AND ASSOCIATES INC
Address: 8279 Midland Rd
Mentor, OH 44060
(440) 951-1380
Funding Agency: Office of Naval Research
PR Number: 00PR03085-00
Award Number: N000140010150
Current End Date: 31-Dec-2000
Scientific Officer: John Zolper

Objective:
Convene experts to explore new approaches to generating mm-wave (>30
GHz) solid state power.
Approach:
A topical workshop will be held where experts will discuss the material
and device challenges to increasing power available from solid state
sources at mm-wave frequencies.

Title: Low Defect Density GaN Substrates from GaN
Boules
PI: Robert Vaudo
ADVANCED TECHNOLOGY MATERIALS INC
Address: 7 Commerce Dr.
Danbury, ct 06810
(203) 207-9368
Funding Agency: Office of Naval Research
PR Number: 00PR03219-00
Award Number: N000140030013
Current End Date: 31-Dec-2002
Scientific Officer: Ingham Mack

Objective:
Develop a manufacturing process that yields 2" diameter (minimum),
semi-insulating GaN substrates with defect densities < 1x104 / cm2 and
prototype substrates with 2.5" diameter (minimum).
Approach:
Commercially-viable GaN substrates will first be developed by growing
HVPE GaN boules on lattice matched GaN seed crystals. HVPE LEO
seeds will also be investigated to reduce the defect density. The most
promising aspects of the HVPE-optical liftoff, HVPE boule growth, and
HVPE LEO processes will then be combined to produce the final wafer
product. Wafer manufacturing, including slicing, sizing, flatting,
polishing, and final surface finishing of the GaN wafers will be an
integral part of the program.

Title: Synthesis of P-type ZnO Films & p-n
PI: Henry White
UNIVERSITY OF MISSOURI COLUMBIA
Dept of Physics & Astronomy
Funding Agency: Office of Naval Research
PR Number: 00PR03564-00
Award Number: N000149910288
Current End Date: 31-Jul-2000
Scientific Officer: Yoon Park

Objective:
The primary goal of this program is to grow and characterize high quality p-type and n-type ZnO films with high carrier concentrations on single crystal substrates, and to fabricate p-n junctions. Secondary goals are the development of materials processing for bandgap modulation, and the development of optical devices such as LEDs and laser diodes. The suitability of several growth techniques to obtain ZnO films with high optical quality and low defect density will be explored.
Approach:
P-type ZnO films will be grown. Films will be characterized by x-ray,
Hall probe, photoluminescence, and atomic force microscopy. The
technique used for growth will be developed further and several
enhancements and other approaches will be explored. Pulsed laser
deposition using ZnO targets will be used to create Zn, O and ZnO
molecules as a precursors to film formation. The impact of oxygen
plasma environments on the growth of ZnO film will be investigated. MBE techniques will also be employed for ZnO film growth.

Title: Bulk Single Crystal Growth of Group III
Nitrides in Supercritical Ammonia
PI: Joseph Kolis
CLEMSON UNIVERSITY
Department of Chemistry
Address: Box 345702
Clemson, SC 296345702
(864) 656-4739
Funding Agency: Office of Naval Research
PR Number: 00PR03597-01
Award Number: N000140010200
Current End Date: 31-Dec-2002
Scientific Officer: Colin Wood

Objective:
To develop a technology for growth of 2" and larger diameter substrates
for power microwave electronics.
Approach:
PI will determine conditions for optimized growth rate and crystal quality of GaN growth from super critical ammonia solutions.
Progress:
PI has determined a phase spce data base for temperature, pressure,
and solubilizing salts for aminothermal growth of GaN.

Title: Growth of Single Crystals and Fabrication
of GaN and AlN wafers
PI: Zlatko Sitar
NORTH CAROLINA STATE UNIVERSITY
MATERIALS SCIENCE AND ENGINEERING
Address: CAMPUS BOX 7919
RALEIGH, nc 276957919
(919) 515-8637
Funding Agency: Office of Naval Research
PR Number: 00PR03598-00
Award Number: N000140010192
Current End Date: 30-Dec-2000
Scientific Officer: Colin Wood

Objective:
To generate procedures and techniques for industrial preparation of
nitride semiconductor sustrates.
Approach:
Sublimation of Ga, and Al under nitrogen atmosphere with additional
ammonia in the case of GaN.

Title: 4 Gbit/in(2) NVRAM Deposition and Testing
PI: Dexin Wang
NONVOLATILE ELECTRONICS INC
Address: 11409 Valley View Dr.
Eden Prairie, MN 55344
(612) 996-1608
Funding Agency: Office of Naval Research
PR Number: 00PR03618-00
Award Number: N0001400C0100
Current End Date: 31-Jan-2003
Scientific Officer: Larry Cooper

Objective:
To provide circuit design and testing of a novel form of Magnetic Random
Access Memory from storage elements designed at NRL.
Approach:
NVE will design the appropriate circuit layouts for the current control of the read and write functions on the Vertical GMR elements designed at
NRL. 2 kilobit memory circuits will be designed, fabricated and tested.
Fabrication will include deposition of metals as per the NRL design,
processing for circuit layout of control wires and readout. Testing will
include wafer validation, single bit and multiple bit sensing. Switching
time effects will be determined.

Title: 11th International Winterschool on New
Developments in Solid State Physics
"Low-Dimensional Systems: Fundamentals and
Applications"
PI: Helmut Heinrich
UNIVERSITY OF LINZ
Institut fur Experimentalphysik
Address: A-4040 Linz
Linz, AZ 22217
(703) 696-4248
Funding Agency: Office of Naval Research
PR Number: 00PR03620-00
Award Number: N000140010236
Current End Date: 31-Jan-2001
Scientific Officer: Larry Cooper

Objective:
To provide a forum for discussions of the latest understanding of the
electronic properties of low dimensional electron devices.
Approach:
The 11th International Winterschool on New Developments in Solid
State Physics-Low Dimensional Systems: Fundamentals and
Applications will be organized on 21-25 February 2000 in Mauterndorf,
Austria. Lectures and discussions will address topics such as phonon
assisted tunneling in nanodevices, spin systems for quantum
computing, terahertz frequency processes in semiconductor
nanostructures, and optical properties of quantum dots.

Title: 2 Inch Bulk GaN Single Crystal Growth from
Liquid Phase
PI: Vladimir DMITRIEV
TECHNOLOGIES AND DEVICES INTERNATIONAL
INC
Address: 8660 DAKOTA DRIVE
GAITHERSBURG, MD 20877
(301) 208-8342
Funding Agency: Office of Naval Research
PR Number: 00PR03621-00
Award Number: N0001400C0168
Current End Date: 14-Feb-2001
Scientific Officer: Colin Wood

Objective:
2 inch diameter single crystal GaN will be grown.
Approach:
PI will seed and grow bulk GaN crystals from atmospheric nitrogen
saturated Ga + other metal alloy solution.

Title: Magnetism & Transport in Semiconductors
PI: Mark Van Schilgaarde
U S DEPARTMENT OF ENERGY SANDIA
NATIONAL LABORATORY
Computational Materials Science
Address:
Albuquerque, NM 871850151
(925) 294-3794
Funding Agency: Office of Naval Research
PR Number: 00PR03634-00
Award Number: N0001499F0152
Current End Date: 31-Mar-2001
Scientific Officer: Larry Cooper

Objective:
To provide ab initio theory for the bandstructure of various semi-conductors, semiconductor heterojunctions and for ferromagnetic
semiconductor-metal heteromaterials. To calculate transport properties
in support of device concepts based on spin polarized electron transport.
Approach:
An all electron GW code will be developed and applied to calculations
of bandstructure for various materials, including III-V compound
semiconductors with accurate band gap determinations. Additional
calculations will address the same materials doped or alloyed with Mn or
Fe to investigate the ferromagnetic properties of these materials. These
calculations will provide the basis for studying the processes of
exchange interactions and spin dynamics in these materials. Transport
of spin polarized carriers in these heterojunction materials will be
assessed, with emphasis on spin flip scattering mechanisms. Separate
code development will lead to calculations of magneto optical properties
for Mn doped III-V compounds.
Progress:
Initial results for LDA calculations for Mn and Fe impurities in GaN
have been obtained. At the 1% level of doping, there is a definite
appearance of majority spin electrons in the gap, and the minority
electrons resonant with the conduction band. At the 3% level, the
majority levels are pushed down into the valence band and since there
are 4 electrons available to fill 5 states, the result is an acceptor state, and the material is metallic in nature. With Fe doping, because there are only 4 states to fill, the material is insulating. More work is needed in order to get bandgap widths correct (always underestimated in LDA) which will affect the spin splitting and thus change the effect of doping on the conductivity.

Title: Magnetic Nanostructure: Support of the
Gordon Research Conference
PI: Carlyle Storm
GORDON RESEARCH CONFERENCES
Director of Gordon Conferences
Address:
West Kingston, RI 028920984
(401) 783-4011
Funding Agency: Office of Naval Research
PR Number: 00PR03638-00
Award Number: N000140010191
Current End Date: 31-Jan-2001
Scientific Officer: Larry Cooper

Objective:
To provide a forum for discussing the latest developments in the physics
and material properties of magnetic nanostructures.
Approach:
The Gordon Research Conference on Magnetic Nanostructures will be
organized and administered on 13-18 February 2000 in Ventura,
California. Topics for discussion include: nanoscale magnetism,
multilayered magnetic films, spin dependent tunneling, new materials,
magnetic sensors, and others.

posted 06-07-2002 02:27 PM            

Title: Quantum 1/f Noise and Decoherence Effects
Applied to Low Dimensionalality
Nanostructures, UHF and Low-Power
PI: Peter Handel
UNIVERSITY OF MISSOURI
341 Woods Hall
Address: 8001 Natural Bridge Rd
St. Louis, MO 63121
(314) 553-5021
Funding Agency: Office of Naval Research
PR Number: 00PR03673-00
Award Number: N000140010199
Current End Date: 31-Jan-2001
Scientific Officer: Larry Cooper

Objective:
To develop an understanding of the sources of 1/f noise in quantum
devices and to provide direction for the improvement of the noise and
decoherence properties of nanoelectronic devices.
Approach:
The concepts of quantum 1/f noise generation in electron devices will be
used to study the various noise sources in Resonant Tunneling Diodes
and in spin polarized electron transport devices. The decoherence
mechanisms which impact on quantum tunneling and on spin flip
processes will be studied. These results will be used to predict the noise performance of such devices and to correlate such results with the
materials and geometries of relevant devices. In particular, phase noise
and amplitude noise will be monitored as they impact on digital
switching devices.

Title: A Study of the Switching Speed of
Magnetoquenched Superconductive Devices &
Their Applicability to Practical
Superconductive Electronics
PI: Steven Kaplan
HYPRES INC
Address: 175 Clearbrook Rd
Elmsford, NY 10523
(914) 592-1190
Funding Agency: Office of Naval Research
PR Number: 00PR03749-01
Award Number: N0001400C0311
Current End Date: 14-Apr-2002
Scientific Officer: Deborah Van Vechten

Objective:
To continue to determine the applicability of mesoscopic
magnetoquenched superconducting valve (MMSV) logic devices to
niobium based Josephson junction technological needs for memory and
field programmable devices in conjunction with the Naval Research
Laboratory (NRL). This technology is a good candidate for the custom
high speed digital processors needed in future generations of rf
multi-function systems.
Approach:
HYPRES will collaborate with NRL in the design, fabrication and test of
MMSV devices to determine their characteristics and switching speed.
The switching speed will be measured using sample probes fabricated
for this project, along with a 1 GHz pattern generator and digital
oscilloscope. The resolution of this measurement should be less than
150 ps. The threshold curve of SQUIDs will be measured, to determine
how the magnetic field of one device affects others. The I-V curve of
quenched devices will be modeled with a resistively-shunted junction
model. In fy00 this will be done with pure Nb devices and in fy01 with
bilayers with lower transition temperatures.

Title: Sb-Based III-V Quantum Devices and Circuits
for Ultra-High Frequency Digital Signal
Processing Applications
PI: David Chow
HRL LABORATORIES LLC
Dept. of Electrical Engineering
Address: 3011 MALIBU CANYON ROAD
MALIBU, CA 902654737
(310) 317-5330
Funding Agency: Office of Naval Research
PR Number: 00PR03836-00
Award Number: N000149830010
Current End Date: 31-Dec-2000
Scientific Officer: Larry Cooper
Objective:
To develop a novel new digital signal processing circuit technology
with speed-power product capability which is orders of magnitude better
than can be expected using conventional silicon technology.
Approach:
The unique properties of Resonant Interband Tunneling Diodes(RITDs) based on InAs/AlSb/GaSb heterojunctions will be used in the development of ultra-high frequency Digital Signal Processing circuits. Optimization procedures for the growth of the materials will be developed. Stacked devices will be designed and tested in circuit simulation programs. Various basic circuits will be evaluated, such as ADCs, digital multipliers and RITD logic gates for FFTs. Particular attention will address the issues of controlled interface morphology in the hetero-junction system which must be improved. Circuits will be fabricated and tested.
Progress:
The physics based RTD model has been optimized by fitting to real
device parameters. The InAs HFET model has also been developed for
use in the SPICE simulations. Several growth runs have been completed
for developing the IC fabrication and processing. The structures are
based on the NRL HFET designs. At Notre Dame, the processing schemes for etching and formation of ohmic contacts are undergoing continuing development. Improvements in the e-beam system have been made and will be used in the gate formation of the HFETs. Equipment for high speed digital measurments has been installed for measurements up to 50 GHz. One main issue has yet to be overcome. Nonuniformity of HFET performance across the chip has not been resolved.

Title: High Speed Resonant Tunneling Circuits
PI: Gary Frazier
RAYTHEON COMPANY DBA RAYTHEON SYSTEMS
COMPANY
Address: 13588 North Central Expwy.
Dallas, TX 752430246
(972) 995-2844
Funding Agency: Office of Naval Research
PR Number: 00PR03837-00
Award Number: N000149830013
Current End Date: 31-Dec-2000
Scientific Officer: Larry Cooper

Objective:
To develop novel Multi-gigahertz digital signal processing circuits for
insertion into various digital systems. These novel circuits will utilize the unique speed and power advantages of Resonant Tunneling Diodes to achieve enhanced level of digital performance.
Approach:
Resonant Tunneling Diodes coupled with Heterojunction Field Effect
Transistors will be combined into novel digital signal processing
circuits. A complete development program will be undertaken in which
the design, fabrication, and testing of the devices and circuits will be
completed. Specific circuits will include shift registers, data latches, and multiplexers. These circuits will be integrated with True Time Delay
networks, code generators, FFT, Data Multiplexers, and Ultra-low power
microwave memory for consideration in the AMRFS system, ATM and broadband wireless networks. III-V semiconductor materials based on
InP and InGaAs layers will be grown for proper integration of RTDs and
HFETs. Various digital circuits operating at 25 GHz will be designed and
fabricated. Circuits will be designed using SPICE codes and advanced
codes provided by the University of Michigan. Circuits will include
on-chip test circuits for testing at the higher digital frequencies.
Progress:
Shift registers and latches that operate at 10 GHz were designed,
fabricated and tested. Based on these results the design of the 25GHz
circuits was completed. S-parameter measurments were made on test
structures at 100 GHz and the results used SPICE modeling of the 25
GHz circuits. Latch circuits were tested at frequencies up to 40 GHz with only 325 microwatts of static power. 1Kbit SRAM were designed,
fabricated and tested. The memory cell requires an area of only 200
square microns and operated up to 3.5 GHz. Compared to CMOS
memory, the TSRAM operates 30 times faster at 3 times lower power.

Title: Nanoscale Interface Characterization by UHV
STM Spectroscopy
PI: Joseph Lyding
THE BOARD OF TRUSTEES OF THE UNIVERSITY
OF ILLINOIS AT URBANA CHAMPAIGN
Beckman Institute-Advanced
Science/Technology
Address: 801 SOUTH WRIGHT STREET
CHAMPAIGN, IL 618204262
(217) 333-8370
Funding Agency: Office of Naval Research
PR Number: 00PR03846-00
Award Number: N000140010234
Current End Date: 31-Dec-2002
Scientific Officer: Larry Cooper

Objective:
To develop improved techniques for characterizing the atomic scale
imaging of semiconductor surfaces and to apply it to several problems
involving the adsorption of various atoms and molecules to these
surfaces.
Approach:
STM based CITS and EELS will be developed for application to surface
imaging and surface spectroscopy of metal films forming on
semiconductor surfaces. UHV capability will allow for experiments of
single atoms adsorbed on silicon surfaces. Electronic properties will
be determined by CITS and chemical properties by EELS. Magnetic atoms
and carbon-60 molecules will be the systems of interest.

Title: Spin Carrier Injection and Oxide Growth at
Interfaces
PI: Norman Tolk
VANDERBILT UNIVERSITY
Departemtn of Physics and Astronomy
Address: Center for Molecular and Atomic
Studies at Su
Nashville, TN 37235
(615) 322-2786
Funding Agency: Office of Naval Research
PR Number: 00PR03852-00
Award Number: N000140010238
Current End Date: 31-Dec-2000
Scientific Officer: Larry Cooper

Objective:
To advance understanding of the effects of interface phenomena in
semiconductor heterostructures using advanced laser light sources.
Materials will be chosen for their potential for advanced devices.
Approach:
The properties of the heterointerfaces of several electronic material
systems will be characterized using the advanced laser facilities at
Vanderbilt. The FEL and other short pulse lasers will be used to
determine band offsets, carrier lifetimes, optical recombination, spin flip scattering times, and others. Using the SHG approach, the properties of charge effects on the silicon-silicon dioxide interface properties will be measured. In-situ characterization is important so that the effects can be monitored as the insulator film begins to form. Magnetic semiconductor films will be studied in magnetic fields to characterize the effects of field controlled band offsets and spin flip scattering events.

Title: Dual Use Bandpass Modulators for RF Signal
Conversion
PI: John Przybysz
NORTHROP GRUMMAN CORPORATION ELECTRONIC
SENSORS AND SYSTEMS DIVISION
Electronic Sensors and Systems Division
Address: 1745A WEST NURSERY RD
Linthicum, MD 210900000
(410) 765-7652
Funding Agency: Office of Naval Research
PR Number: 00PR04121-00
Award Number: N000140030022
Current End Date: 19-Mar-2003
Scientific Officer: Deborah Van Vechten
Objective:
To prove that a superconducting, oversampled ADC can outperform its
semiconductor competition in conventional narrow band, low pass
versions and can be generalized in a straight-forward manner into
revolutionary narrow band, bandpass designs. The first realization of the latter will be matched to the GPS 1.5 GHz band and serve to provide
jamming resistance to this militarily critical signal. Commercialization
will be first pursued at the technically easier, lower wireless
communications frequencies. Demonstration of a pass band adc at these
frequencies will enable construction of ultra-wide band receivers which
do not down-convert the signal, separate digitization and output signal
generation functions, and are truly multi-functional.
Approach:
In the first year, the existing second order, low pass, sigma delta ADC
design will be iterated and fabricated in >3X reduced line width to allow clock speeds above the demonstrated 2.5 GHz. Export of data to
semiconducting electronics at sampling speed will be worked. The issues
involved in shifting to a band pass design will be investigated via
software simulations. Experimental fabrication and testing of the band
pass design will begin in the second year and culminate at the end of
this funding with a test of noise shaping and the SNR and SFDR
achieved in the GPS 1.5 GHz band. Initially the fabrication will be done at UC Berkeley under a separate ONR award, but later the new, reduced line width process at NG will take over. NG will also collaborate with another ONR award participants at SUNY SB (which will develop the digital resampling filters needed for the wide band receiver architecture) to define the signal interfaces and extent of preprocessing of the data in the ADC digitizers.

Title: Ultrafast Optoelectronic Input-Output
Interface for Superconducitng Digital
Electronics
PI: Roman Sobolewski
UNIVERSITY OF ROCHESTER
Dept of EE & Laboratory for Laser
Energies

Funding Agency: Office of Naval Research
PR Number: 00PR04124-00
Award Number: N000140010237
Current End Date: 30-Sep-2001
Scientific Officer: Deborah Van Vechten

Objective:
Superconducting digital electronics represents one of the prime
contenders for the role of high speed signal conversion and digital
processing in Navy direct rf reception systems due to their suitability for use in 100 GHz or higher logic circuits. However, there are currently difficulties with getting the processed signals out of the low temperature environment at high speed without large heat loads (3X that of processor) thanks to the losses and thermal conductivity of copper leads. Reciprocally, optical communications systems need help with switching and routing, simple computational tasks. (It is estimated that by the year 2006, nearly 13% of developed world households will be connected to interactive broadband fiber services, requiring very high capacity networks with complex switchboards and routers.) The system concept that is being explored is the combination of low loss optical fiber data transmission with superconducting logic. This will complete work on optical to electronic conversion using hot electron bolometers and explore a new class of electrical to optical converters, magneto-optical modulators (MO). By the end of the work, it should be clear if MO are a good choice for data transmission at speeds to 100 GHz per optical channel with low thermal loading.
Approach:
The MO modulator has distinct advantages over EO devices since MO are
current not voltage driven, just like superconducting circuits. Currents
of the required 1 mA magnitude flowing in a microwave microstrip line (MSL) built on a polarization-sensitive MO active medium and interacting with cw light delivered to low temperature by an optical fiber is expected to achieve at least 10% phase modulation for a single pass
of SFQ signals with band widths above 100 GHz. EuSe or EuS biased at
4K are both expected to be suitable MO materials when a commercial
green light laser is used. A Mach-Zehnder interferometer on the output
will convert the phase modulation to amplitude modulation and strip off
the unmodulated light signal. The MO modulators will be characterized
in the frequency domain using GHz-range microwave sources and a
50-GHz bandwidth oscilloscope. Time-domain characterization will
include analysis of the device optical response as the current pulse
propagates in the MO transmission line using a unique femtosecond
Ti:Sapphire laser/amplifier system and a cryogenic electro-optic (EO)
sampler. TRW will be a collaborator.

Title: Lumped Josephson Junction Arrays for Low
Phase Noise Arbitrary Waveform Synthesizers
PI: Samuel Benz
U S DEPARTMENT OF COMMERCE NATIONAL
INSTITUTE OF STANDARDS AND TECHNOLOGY
Electromagnetic Technology Division
Address: 325 BROADWAY
BOULDER, CO 80303
(303) 497-5258
Funding Agency: Office of Naval Research
PR Number: 00PR04125-00
Award Number: N0001400F0154
Current End Date: 30-Sep-2001
Scientific Officer: Deborah Van Vechten

Objective:
The next innovation in rf transmitters will use a digital pulse train to
represent the desired output signal until just before the signal is
actually transmitted. The performance of the system when used in a
Doppler radar mode is a very strong function of the phase and amplitude purity of the waveform. Passing the pulse train through an array of Josephson junctions is known to improve this purity by >40 dB.This work will continue the development of electrically lumped versions of these arrays that are expected to be much easier to use than distributed arrays and more wide band in their response.
Approach:
Large numbers of junctions (>10^4) must be in the array if it is to
produce a sizable voltage. For its response to be lumped at the highest
frequency used, all the devices must be located within a small fraction of a wavelength at the highest frequency. Thus junctions must be less
than 100 nm apart. Both vertically stacked SNS arrays (Nb/Ti/Nb? and
NbN/MgO/NbN? are being tried) and laterally arrayed junctions
(suitable for YBCO devices) are being investigated.

Title: Solid State Module & Components II
PI: Jeff Lynch
NORTHROP GRUMMAN CORPORTION
Electronic Sensors & Systems Sector
Address: PO Box 17319
Baltimore, MD 21203
(410) 765-4972
Funding Agency: Office of Naval Research
PR Number: 00PR04206-00
Award Number: N0001400C0152
Current End Date: 24-Jan-2001
Scientific Officer: John Zolper

Objective:
To increase the upper frequency limit of a high power SiC static
induction transistor.
Approach:
An inverted SiC SIT structure will be studied that employs an implanted
p-gate. The inverted device has lower parasitic capacitance and hence
should exhibit a higher cut off frequency.

Title: Gordon Research Conference:Chemistry and
Physics of Nanostructure Fabrication
PI: Carlyle Storm
GORDON RESEARCH CONFERENCES
Director of Gordon Conferences

Funding Agency: Office of Naval Research

PR Number: 00PR04220-00
Award Number: N000140010235
Current End Date: 31-May-2001
Scientific Officer: Larry Cooper
Objective:
To provide a forum to discuss the latest results in the methods of the
fabrication of nanoscale electronic devices.
Approach:
The Gordon Conference on Chemistry and Physics of Nanostructure
Fabrication will be organized in Tilton College, New Hampshire on 23-28
July 2000. A forum will be provided to discuss results in the methods
for fabrication of nanostructure electronic devices. Topics will include: proximal probe fabrication, manipulation and measurement; single electron phenomena; quantum devices; novel devices; chemical and
biological nanostructures.

Title: A Variable Digital Time Delay Element
PI: S. Kent
RAYTHEON COMPANY DBA RAYTHEON SYSTEMS
COMPANY
Address: 3100 W Lomita Blvd
Torrance, CA 905092999
(310) 517-6256
Funding Agency: Office of Naval Research
PR Number: 00PR04226-00
Award Number: N0001499C0180
Current End Date: 30-Apr-2000
Scientific Officer: John Zolper

Objective:
Develop a circuit design for a variable digital time delay element in
accordance with the AMRFS low (1-5 GHz) and high (4-20 GHz) bands.
Approach:
The contractor will perform a design study to develop a digital
variable time delay element in accordance with the AMRFS low and high
bands. Implementation of the design in SiGe, InP and GaAs based
circuit technology will be examined. A complete circuit design and
recomendation for implementation will be delivered.
Progress:
The major tasks completed include System Requirements & Program
Development, which was used to establish the primary system
requirements. The development of filter coefficients has progressed as
planned, producing methods for generating coefficients. The filter
structures have been examined. The basic FIR structure has been
examined, and it presents a proven approach to filter-implemented
delays. Development of the Farrow structure is underway and its
effectiveness is being assessed. Preliminary results indicate a modified structure is preferred and increased attention to coefficient design is necessary.

Title: MEMs Tunable Planar Micromachined & Bulk
Acoustic Waver Filters
PI: Peter Petre
HRL LABORATORIES LLC
Address: 3011 Malibu Canyon Rd
Malibu, CA 90265
(310) 317-5919
Funding Agency: Office of Naval Research
PR Number: 00PR04230-00
Award Number: N0001499C0178
Current End Date: 30-Apr-2002
Scientific Officer: John Zolper

Objective:
Develop a discretely tunable pre-select filter module for the 4-20
GHz frequency band and a 3- to 5- channel integrated filter module for
the 1 - 5 GHz frequency band compatible with AMRFS specifications.
Approach:
Contractor will develop a Microelectromechanical System-based (MEMs) discretely tunable 32-channel integrated pre-select filter module for the high frequency (4 to 20 GHz) AMRFS system and a MEMS discretely tunable 3- to 5-channel Bulk Acoustic Wave (BAW) integrated filter module for the low frequency (1 to 5 GHz) AMRFS.
Progress:
A new MEMs switch is designed and is being fabricated that is modeled
to have switching speeds approaching 1 ms. Material development of
high quality thin film AlN for SAW filters is completed. Packaging
technology for integration of miniature filter banks is under
development, including substrate vias.

Title: Low Noise Amplifiers
PI: Armand Poirier
SANDERS A LOCKHEED MARTIN COMPANY
Microwave Space & Mission Electronics
Division
Address: 65 Spit Brook Rd
Nashua, NH 030610868
(603) 885-5090
Funding Agency: Office of Naval Research
PR Number: 00PR04235-00
Award Number: N0001499C0164
Current End Date: 30-Mar-2001
Scientific Officer: John Zolper

Objective:
Demonstrate a low noise amplifier over 4 to 20 GHz to achieve the
AMRFS goals of NF = 1.0 dB, TOI > 32 dBm, SOI > 40 dB, gain = 20 dB,
and DC power = 0.6 W.
Approach:
The contractor will develop enhanced linearity PHEMTs and
throroughly characterize the devices for nonlinear and low noise
behavior. Advanced circuit techniques, including a wide band balun,
will be employed to achieve the required second and third order
intercepts for linearity.
Progress:
New start. No progress to report.

Title: Wideband GaAs Metamorphic HEMT LNA for
Advanced Multifunction RF Systems
PI: William Hoke
RAYTHEON SYSTEMS COMPANY
Address: Advanced Device Center
Andover, MA 01810
(978) 470-9592
Funding Agency: Office of Naval Research
PR Number: 00PR04236-00
Award Number: N0001499C0177
Current End Date: 31-May-2002
Scientific Officer: John Zolper

Approach:
The contractor will advance the state-of-the-art of metamorphic high
electron mobility transistors (MHEMT) for use in a 4-20 GHz low noise
amplifier (LNA) in accordance with the AMRFS system specifications.
Both device and circuit level innovations, including an active cold load, will be explored to achieve the noise figure, gain, and bandwidth
Progress:
The progam was started 21 July 1999. Initial circuit implentation of an
active cold load were realized in 1-5 GHz LNA with an effective load
temperature of 80 K realized. This technique is being applied to circuits designed for 4-20 GHz operation. New device structures are being explored to improve linearity by increasing the transistor breakdown.

Title: Interfacial Magnetospectroscopy of Advanced
Magnetic Layered Systems
PI: Yves Idzerda
NAVAL RESEARCH LABORATORY
Materials Science and Technology
Division
Address: NRL 6345
Washington, DC 203755320
(202) 767-3603
Funding Agency: Office of Naval Research
PR Number: 00PR04246-00
Award Number: N0001400WR20242
Current End Date: 30-Sep-2000
Scientific Officer: Larry Cooper

Objective:
To investigate the magnetic properties of the interface between various
electronic materials which determine the transport spin polarized
carriers.
Approach:
Polarized synchrotron radiation sources will be used to characterize the
magnetic properties of various electronic materials in thin film form. Metal-semiconductor and insulator-semiconductor films will be included. X-ray Magnetic Circular Dichroism and X-ray Resonant Magnetic Scattering techniques will be used to determine the chemical specific sources of magnetic properties at these interfaces.

Title: Surfaces and Interfaces in InxGa1-xAs in
Single Quantum Wells and in
PI: Harry Wieder
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA SAN DIEGO 0934
Electrical & Computer Engineering
Address: 9500 Gilman Drive, USCD
La Jolla, CA 920930407
(619) 534-2486
Funding Agency: Office of Naval Research
PR Number: 00PR04261-00
Award Number: N000140010328
Current End Date: 31-Jan-2001
Scientific Officer: Larry Cooper

Objective:
To determine and control the effects of alloying in InGaAs/InP
heterojunctions leading to optimization of the transport properties of
these materials.
Approach:
Heterojunction materials of InGaAs/InP thin films will be grown with
various levels of In. Electronic and transport measurements will be made
to understand the role of surface states and their contribution to the
accumulation of electrons at the interface. Varying the In content will be used to deduce the relationship between the surface state levels and
the location of the Fermi level.

Title: ADMINISTRATIVE & ENGINEERING SERVICES IN
SUPPORT OF THE ADVISORY GROUP ON ELECTRON
DEVICES (AGED)
PI: Mark Pacer
WRIGHT PATTERSON AFB
Address: 2241 AVIONICS CIRCLE
WPAFB, OH 454337322
(937) 255-4831
Funding Agency: Office of Naval Research
PR Number: 00PR04277-00
Award Number: N0001400MP20052
Current End Date: 30-Sep-2000
Scientific Officer: Ingham Mack

Objective:
To provide technical and management support for the DoD Advisory
Group on Electron Devices, the AGED Executive Director, and the
Electronics portion DoD Reliance Technology Panel for Sensors,
Electronics, and Battlespace Environments. The function of AGED is to
provide technical advice to assist the DoD, Military Departments, and
NASA plan and direct electronic device programs to meet present and
future system needs.
Approach:
The AGED Main Group and Working Groups, which consists of
representatives from each of the Services as well as private industry,
hold meetings on a regular basis to plan and hold Special Technology
Area Reviews to help determine future directions of the Services'
Electronics programs. Through the DoD Reliance Panel on Sensors,
Electronics, and Battlespace Environments, the AGED Secretariat
assists in gathering the appropriate technical and financial information
so that a jointly-planned Electronics program can be more effectively
implemented.
Progress:
During FY99 the contractor prepared for, assisted in running, and
performed the necessary follow-up on the following: 6 Meetings each of
the AGED Main Group, Working Groups A, B, and C, TPED, and the
1999 TARA. Three STARs were conducted on the subjects of Reliability,
Packaging, and Low Cost Lasers. In addition, the contractor assisted in
providing information and material for meeting the needs of DDR&E,
AGED, and TPED.

Title: ADMINISTRATIVE & ENGINEERING SERVICES IN
SUPPORT OF THE ADVISORY GROUP ON ELECTRON
DEVICES (AGED)
PI: Mark Pacer
AIR FORCE MATERIAL COMMAND
Address: 2241 AVIONICS CIRCLE
WPAFB, OH 454337322
(937) 255-4831
Funding Agency: Office of Naval Research
PR Number: 00PR04279-00
Award Number: N0001400MP20054
Current End Date: 30-Sep-2000
Scientific Officer: Ingham Mack

Objective:
To provide technical and management support for the DoD Advisory
Group on Electron Devices, the AGED Executive Director, and the
Electronics portion DoD Reliance Technology Panel for Sensors,
Electronics, and Battlespace Environments. The function of AGED is to
provide technical advice to assist the DoD, Military Departments, and
NASA plan and direct electronic device programs to meet present and
future system needs.
Approach:
The AGED Main Group and Working Groups, which consists of
representatives from each of the Services as well as private industry,
hold meetings on a regular basis to plan and hold Special Technology
Area Reviews to help determine future directions of the Services'
Electronics programs. Through the DoD Reliance Panel on Sensors,
Electronics, and Battlespace Environments, the AGED Secretariat
assists in gathering the appropriate technical and financial information so that a jointly-planned Electronics program can be more effectively implemented.

Title: Electronics and Magnetism at the Nanometer
Scale
PI: Joseph Stroscio
U S DEPARTMENT OF COMMERCE NATIONAL
INSTITUTE OF STANDARDS AND TECHNOLOGY
Electron and Optical Physics Division
Address: OFFICE OF COMPTROLLER BLDG 101 A807
Gaithersburg, MD 20899
(301) 975-3716
Funding Agency: Office of Naval Research
PR Number: 00PR04293-00
Award Number: N0001400F0278
Current End Date: 30-Sep-2002
Scientific Officer: Larry Cooper
Objective:
To determine the magnetic and structural properties of nanometer
scale structures fabricated on semiconductor and metal surfaces and
determine the device implications.
Approach:
A novel low noise scanning tunneling microscope will be used to
image the atomic structure of semiconducting and metallic surfaces and
to identify the surface atoms using spectroscopic techniques. This
information will be correlated with magnetic properties determined by
SMOKE and SEMPA. Novel new techniques will be explored for determining the magnetic properties of such films. One approach will be spin dependent tunneling. Another approach will be polarization analysis of luminescence caused by spin dependent tunneling.
Progress:
STM measurements on Mn deposited on Fe surfaces have been made as a function of Mn thickness. Mn islands form as coverage increases
with a unique development of various size islands. SEMPA measurements of the interlayers exchange coupling show clearly the switching between negative and positive coupling as the number of layers changes between odd and even values. These observations are in agreement with the Sloncewski torsion model.

Title: Support for Advisory Group on Electron
Devices (AGED) and DoD Technology Panel on
Electron Devices (TPED)
PI: Ted Reiss
US ARMY RESEARCH LABORATORY
Sensors & Electron Devices Directorate
Address: 2800 Powder Mill Road
Adelphi, MD 207831197
(301) 394-1193
Funding Agency: Office of Naval Research
PR Number: 00PR04320-01
Award Number: N0001400MP20089
Current End Date: 30-Sep-2000
Scientific Officer: Ingham Mack

Objective:
To provide technical and management support for the DoD Advisory
Group on Electron Devices, the AGED Executive Director, and the
Electronics portion DoD Reliance Technology Panel for Sensors,
Electronics, and Electronic Warfare. The function of AGED is to provide
technical advice to assist the DoD, Military Departments, and NASA plan
and direct electronic device programs to meet present and future
system needs.
Approach:
The AGED Main Group and Working Groups, which consists of represen-tatives from each of the Services as well as private industry, holds meetings on a regular basis to plan and hold Special Technology Area Reviews to help determine future directions of the Services' Electronics programs. Through the DoD Reliance Panel on Sensors, Electronics, and Electronic Warfare, the AGED Secretariat assists in gathering the appropriate technical and financial information so that a jointly-planned and executed program can be more effectively implemented.
Progress:
New start. No progress to report.

Title: Programmable Digital Re-Sampling Filter for
a Generic Wide-Band AMRFS Receiver Element
PI: Joseph Jensen
HRL LABORATORIES LLC
Address: 3011 MALIBU CANYON ROAD
MALIBU, CA 90265
(310) 317-5250
Funding Agency: Office of Naval Research
PR Number: 00PR04447-00
Award Number: N0001400C0167
Current End Date: 30-Nov-2000
Scientific Officer: Deborah Van Vechten

Objective:
To conceptualize and evaluate alternative architectures for a novel class of digital filter units that will enable the AMRFS goal of making the entire sampled rf spectrum available to an arbitrary number of
simultaneous users via an unrestrained number of beams. The Navy
needs high speed, large dynamic range RF receivers and supporting
digital processors in high performance radars to provide ship
self-defense and more generally needs multiple simultaneous beams
and reallocatable functionality beams to create affordable, high
performance rf systems for future platforms.
Approach:
The architectural study of the filter units considered for this application will address the AMRFS requirements of angular resolution of the center line of incoming wave-fronts, sharpness in the passband edges of multiple passbands, decimation, and minimization of circuit complexity. The resulting design should be largely optimized for realization behind every array element and in any 100 GHz digital technology.

Title: Cooperative Research on a Novel Josephson
Junction Structure for High Speed Digital
Applications
PI: John Ketterson
NORTHWESTERN UNIVERSITY
Department of Physics and Astronomy
Address: 633 Clark Street - Room 2-502
Evanston, IL 60208
(312) 491-5468
Funding Agency: Office of Naval Research
PR Number: 00PR04558-00
Award Number: N000140010025
Current End Date: 30-Dec-2002
Scientific Officer: Deborah Van Vechten

Objective:
Superconducting digital electronics is a promising 100 GHz capable
digital technology which could find Navy application in wide band,
multi-function rf systems. However, it is not clear that the device
geometry used for the past 10 yrs is optimal for such high clock speeds.
This work will insure international collaboration and thereby aid in the
investigation of whether a promising alternative structure (SINIS) is in
fact easier to fabricate with little variation among devices.
Approach:
Support twice yearly meetings of the 2 ONR sponsored U.S. groups with
the 3 E.U. sponsored groups and a Ukranian theorist actively studying
the alternative device structure to discuss recent progress and technical issues.

Title: Solar Blind Detector Array Program
PI: Bruce Baran
LOCKHEED MARTIN CORPORATION
IR Imaging Systems
Address: 2 Forbes Rd
Lexington, MA 021737393
(781) 863-3574
Funding Agency: Office of Naval Research
PR Number: 00PR04579-00
Award Number: N0001499C0138
Current End Date: 09-May-2002
Scientific Officer: Yoon Park
Objective:
The goal is to develop the technologies necessary to produce AlGaN photodetectors which are suitable for vehicle self-protection systems. The application requires UV focal plane arrays which are capable of counting photons.
Approach:
A consortium consisting of Lockheed Martin, Epitronics, Emcore and
University consultants will be formed. The contractor will attack
issuses involved in materials, device design and systems engineering in developing the vehicle self-production technology. Low noise
Avalanche Photodiodes, with internal gain, will be developed. All
devices fabricated to date have noise characteristics many orders of
magnitude away from the established needs. Issues to improve gain
and noise will be addressed in this program. The program will address
the issues such as (1) the improvement of the material quality, (2) the
development of low damage etch processes and (3) the design and
development of an ultra-low noise readout structure. A 128 x 128 AlGaN
focal plane array wiil be fabricated.
Progress:
New start. No progress to report.
Title: Advanced Physical Vapor Transport Growth of
Pure & Modified AIN Crystals
PI: N. Singh
NORTHROP GRUMMAN CORPORATION ELECTRONIC
SENSORS AND SYSTEMS DIVISION
Science & Technology Center
Funding Agency: Office of Naval Research
PR Number: 00PR04588-00
Award Number: N0001400C0214
Current End Date: 30-Sep-2001
Scientific Officer: Colin Wood
Objective:
To use the high surface mobility of haloenated group IV molecules in
increasing the growth rate and reducing defect densities of SiC bulk
crystal growth for wide gap semiconductor electronics.
Approach:
PI will use halogenated vapor sources of carbon and silicon for growth of SiC boules.

Title: Growth of Bulk Gan by LPE
PI: Michael Spencer
CORNELL UNIVERSITY
Department of Electrical Engineering
Address: 120 Day Hall
Ithaca, NY 14852
(607) 255-6271
Funding Agency: Office of Naval Research
PR Number: 00PR04592-00
Award Number: N000149810071
Current End Date: 30-Mar-2003
Scientific Officer: Colin Wood

Objective:
Preparation of semiconductor grade GaN bulk crystals as substrates
for high quality epitaxial films.
Approach:
GaN will be recrystalized from molten metalic solutions.
Progress:
All first round modifications to equipment are placed. Early growth runs
have shown remarkably improved crystal quality. However the seed
crystal problem is not resolved. PI will try to procure small seeds from
the High Pressure Institute in Poland.

Title: Ultra Wideband, High Power, Isolators for
AMRFS Proposal
PI: J. Adam
NORTHROP GRUMMAN CORPORATION ELECTRONIC
SENSORS AND SYSTEMS DIVISION
Electronic Sensors & Systems Division
Funding Agency: Office of Naval Research
PR Number: 00PR04615-00
Award Number: N0001400C0173
Current End Date: 30-Sep-2000
Scientific Officer: John Zolper

Objective:
To model, design, and fabricate a prototype 1-5 GHz isolator with < 0.5
dB insertion loss and > 20 dB isolation.
Approach:
The approach will be to first perform extensive modeling and design
comparisons of potential isolator designs, down select the best
approach, and then fabricate a prototype part.

Title: Robust AlGaN/GaN MODFET LNA's
PI: Mehran Matloubian
HRL LABORATORIES LLC
Address: 3011 Malibu Canyon Road
Malibu, CA 90265
(310) 317-5363
Funding Agency: Office of Naval Research
PR Number: 00PR04616-00
Award Number: N0001400C0174
Current End Date: 31-Mar-2001
Scientific Officer: John Zolper

Objective:
To study the trade-offs between survivability and low
noise performance of AlGaN MODFETs and hybrid amplifiers.
Approach:
Various AlGaN MODFET structures will be grown, fabricated, and
characterizated for survivability and microwave noise at 10 GHz. Device
circuit and large signal models will be developed to determine the
controlling device factors for the noted performance.

Title: Ultra-Wideband AlGaN Amplifier Development
PI: Rowan Messham
NORTHROP GRUMMAN CORPORATION
Funding Agency: Office of Naval Research
PR Number: 00PR04660-00
Award Number: N0001495C0171
Current End Date: 31-Jul-2001
Scientific Officer: John Zolper

Objective:
The research will focus on the development of an ultra-wideband
AlGaN/GaN amplifier. This expands on the small signal amplifier task
of the orginal contract. An amplifier will be fabricated from AlGaN/GaN
high electron mobility transistors (HEMT) grown on SiC substrates.
Material will be prepared both via a low dislocation density laterial
epitaxial overgrowth (LEO) process and conventional direct epitaxy on
SiC. Device performance goals include power density > 4 W/mm ay 10
and 18 GHz with breakdown voltages > 50 V. A distributed amplifer will
be designed and fabricated to produce 3 W over the full 1 - 18 GHz
bandwidth. As a preliminary task, a 1 W, 1 - 18 GHz amplifer will be
produced as a drop in replacement for the present GaAs power amplifier in the microwave power module (MPM) under development by Northrup Grummond for The Naval Research Laboratory. The final phase of the contract will involve designing a power combining amplifer to deliver >50 W of power over 1 - 18 GHz.
Approach:
AlGaN/GaN HEMTs wafers will be grown by Prof. Bob Davis at NCSU
and delivered to Northrup Grumman for processing. Device modeling
will be done by Prof Michael Shur at RPI. Both LEO and conventional
epitaxial structures will be studied. At least 2 process runs of 0.25
micron HEMTs will be made. Various surface passivation techniques,
including dielelectric and undoped GaN surface layers, will be studied
to improved high frequency gain. High voltage passive components will
be developed. Source inductance will be reduced through wafer
vias. Via holes will also be used under inductors, along with airbridge
interconnects, to reduce the capacitance under biasing inductors.
Progress:
0.7 micron gate length AlGaN/GaN HEMTs grown on SiC have achieved
2 W at 10 GHz. The HEMT had an fmax of 35 GHz and Imax of 1.2
A/mm. A hybrid distributed SiC amplfier delivered a record 6.8 W over
band from 3-9 GHz. Initial studies of an undoped GaN passsivation
layer to reduce trapping effects were performed and reduced trapping
was achieved.

Title: HVPE Growth of Semi-Insulating GaN Buffer
Layers for Microwave Device Applications
PI: R. Molnar
HANSCOM AIR FORCE BASE
Funding Agency: Office of Naval Research
PR Number: 00PR04662-00
Award Number: N0001400MP20070
Current End Date: 30-Sep-2000
Scientific Officer: Colin Wood

Objective:
To generate a low cost electronic grade substrate supply for lattice
matched nitride semiconductor high power electronics.
Approach:
PI will introduce boron nitride liners to the reaction tube to reduce Si
and O concentrations/electrical conductivity of these films, and will
develop laser induced substrate-epilayer separation.

Title: Low Temperature Preparation of 4H SiC
(0001) Surfaces for Epitaxial Growth
Utilizing a Novel Atomic Hydrogen Source
PI: John Wolan
MISSISSIPPI STATE UNIVERSITY
Chemical Engineering
Address: PO Box 6156
Mississippi State, ms 39762
(601) 325-8249
Funding Agency: Office of Naval Research
PR Number: 00PR04667-00
Award Number: N000140010276
Current End Date: 30-Mar-2003
Scientific Officer: Colin Wood

Objective:
Very high crystal perfection SiC surfaces for low breakdown leakage
devices.
Approach:
Low temperature atomic hydrogen beams in vacuum will impinge upon
SiC surfaces, thus etching away surface through sub-surface residual
damage from cutting and polishing of bulk SiC crystals, without
introducing macroscopic damage.

Title: Heteroepitaxy of Device Quality B-GaN on
B-SiC Conversion Layers
PI: Charter Stinespring
WEST VIRGINIA UNIVERSITY RESEARCH
CORPORATION ON BEHALF OF WEST VIRGINIA
UNIVERSITY
Department of Chemical Engineering
Address: PO BOX 6845 617 N SPRUCE STREET
MORGANTOWN, WV 265066845
(304) 293-2111
Funding Agency: Office of Naval Research
PR Number: 00PR04671-00
Award Number: N000140010293
Current End Date: 28-Feb-2001
Scientific Officer: Colin Wood

Objective:
To develop a supply of cubic wide gap semiconductor heterojunctions for
high power semiconductor electronic components.
Approach:
Silicon surfaces will be coated by methyl radicals to form silicon carbide monolayers. The silicon carbide will then be used to nucleate beta GaN epitaxial thin firms for HBTs.

Title: Engineered Interface Electronic Structures
of III-Nitride Heterostructures
PI: Robert Nemanich
NORTH CAROLINA STATE UNIVERSITY
Department of Physics
Address: Campus Box 8202
Raleigh, NC 276958202
(919) 515-3225
Funding Agency: Office of Naval Research
PR Number: 00PR04813-00
Award Number: N000140010292
Current End Date: 31-Dec-2000
Scientific Officer: Larry Cooper

Objective:
To use in-situ surface analysis techniques for investigations of the
growth of heterojunction materials involving SiC and GaN with the goal
of optimizing the properties of such materials by engineering the
interface between the dissimilar materials.
Approach:
Photo Electron Emission Microscopy will be used to monitor the
electronic and structural properties of the growth of thin GaN films on
SiC substrates. Tunable radiation from a Free Electron Laser will be
used as a probe of the chemical/electronic nature of the buried
interfaces. The spectroscopic equipment will be used in-situ with a UHV
growth chamber for real-time characterization of the growing film.
Spatial resolution for monitoring surface morphology will achieve 10
nanometers.

Title: Strain and Oxygen Stoichiometry Effects on
High Temperature Superconductor Thin Films
and Devices
PI: Xiaoxing Xi
THE PENNSYLVANIA STATE UNIVERSITY
Department of Physics
Address: 104 Davey Laboratory
University Park, PA 16802
(814) 863-5350
Funding Agency: Office of Naval Research
PR Number: 00PR04822-00
Award Number: N000140010294
Current End Date: 30-Sep-2000
Scientific Officer: Deborah Van Vechten

Objective:
To determine whether the formation of spatial stripes of differing
electron density in mixed valency compounds is impacted by the global
stress in the film and to define the effect of such stripes on the electrical properties of the materials.
Approach:
Fabricate thin film samples of La2-x SrxCuO4-delta on vicinal substrates
that have separately varied stress and oxygen content. Personally
investigate the impact of these 2 parameters and the degree of in-plane
order on the transition temperatures in the superconducting state and
into a low temperature tetragonal phase. Distribute as agreed (after
consultation with ONR PO) samples to other researchers who will
examine other aspects of their electrical properties.

Title: Integrated Electronics for Vertical (CPP)
GMR MRAM
PI: John Anderson
NONVOLATILE ELECTRONICS INC
Address: 11409 Valley View Rd
Eden Prairie, MN 553443617
(612) 829-9217
Funding Agency: Office of Naval Research
PR Number: 00PR04875-00
Award Number: N0001400C0236
Current End Date: 31-Aug-2002
Scientific Officer: Larry Cooper

Objective:
To develop the technology and designs to implement a magnetic memory
concept for high density, non-volatile circuits for both commercial and
military applications.
Approach:
CMOS circuit designs will be made to support the control (read/write) of
vertical MRAM elements. CMOS circuits will be fabricated at a foundry
and returned for further processing of MRAM memory circuits as a
separate process. Processing will include mask development, deposition
of metal layers and read/write metalization followed by chemical-mechanical polishing and packaging will follow. Testing of memory function for small modular memory blocks, and then for multiple modules, will be followed by full chip level integration of a 2 Kilobit memory demonstration.
Progress:
This is an SBIR effort.

Title: High Speed Quantum Devices and Circuits
PI: Harold Grubin
SCIENTIFIC RESEARCH ASSOCIATES INC
Division of Marine Biology and
Address: 50 NYE ROAD PO BOX 1058
GLASTONBURY, CT 06033
(203) 659-0333
Funding Agency: Office of Naval Research
PR Number: 00PR04876-00
Award Number: N0001400C0237
Current End Date: 31-May-2002
Scientific Officer: Larry Cooper

Objective:
To develop a computer simulation code for the design of semiconductor
tunneling devices which can provide data necessary for the design of
quantum-device based, high frequency circuits.
Approach:
Quantum transport models for quantum tunneling in semiconductor
devices based on the Wigner Function. Transport equations will be
developed to include large signal switching effects. The modeling will be applied to resonant tunneling relaxation oscillations as a demonstration of the design capability of the simulator. The RTRO will be optimized for 100+ Gigahertz clock applications. Noise sources will be studied and the effects of circuit designs which can reduce 1/f noise will be considered. The simulator will be optimized for commercial marketing, and will require development of appropriate user interfaces. Simulations will be validated with comparisons to device performance obtained from various groups performing experiments on approved device models.
Progress:
This is an SBIR effort.

Title: Workshop on Wide Bandgap Bipolar Devices -
Proceedings Distribution
PI: Shari Allwood
ALLWOOD AND ASSOCIATES INC
Address: 8279 Midland Rd
Mentor, OH 44060
(440) 951-1380
Funding Agency: Office of Naval Research
PR Number: 00PR04903-00
Award Number: N000140010318
Current End Date: 09-Jul-2000
Scientific Officer: John Zolper
Objective:
Dessiminate information on progress in wide bandgap bipolar devices.
Approach:
A workshop was held in February 1999 on wide bandgap bipolar devices
and manuscripts were submitted by attendees to a special issue of Solid
State Electronics. The issue is now being distributed to the workshop
attendees.

Title: Interfacing Magnetoelectronics with
Biochemistry Processes
PI: Jeffrey Byers
NAVAL RESEARCH LABORATORY
Materials Science and Technology
Address: NRL 6345
Washington, DC 203755320
(202) 767-6147
Funding Agency: Office of Naval Research
PR Number: 00PR05198-00
Award Number: N0001400WX21069
Current End Date: 30-Sep-2000
Scientific Officer: Larry Cooper

Objective:
To develop novel nanoscale magnetic devices and use them to
manipulate receptor-ligand interactions in biomolecular systems.
Further, the technique of using magnetic nanoparticles, coupled to
biomolecular species, as a method to control biomolecular processes will
be validated.
Approach:
Nanometer scale magnetic devices will be fabricated so that the fringing
fields can be controlled. Magnetic multilayer structures will be tailored to engineer the fringing field of the device. Magnetic nanoparticles will be biofunctionalized with appropriate ligands for study of controlled ligand-receptor processes. AFM techniques, coupled with DNA molecules tethered to solid surfaces will manipulate the nanoparticles for attachment to the DNA. Magnetic field manipulation of the nanoparticles by the fringing field devices will then permit exploration of controlled biomolecular processes. One study will use avidin (with a fluorescein group) as the protein receptor and the molecule biotin as the ligand. Then flourescence measurments can resolve the competition of the biotin and the fluorescein binding for the receptor site.

Title: A Cryogenic Loop for Cooling Spatially
Separate Electronics
PI: Jeffery Didion
NATIONAL AERONAUTICS AND SPACE
ADMINISTRATION
Address: Mail Code 545
Greenbelt, MD 207710000
(301) 286-4363
Funding Agency: Office of Naval Research
PR Number: 00PR05201-00
Award Number: N0001400F0216
Current End Date: 30-Sep-2000
Scientific Officer: Deborah Van Vechten

Objective:
Determine whether and how efficiently nitrogen may be pumped using
a static electric field. The answers will strongly impact whether localized spot cooling can be used to reduce the total refrigeration cost of advanced superconducting circuits that require cryogenic conditions. Such a reduction will make more facile the actual fielding of such circuits in rf systems where their superior performance would be highly useful.
Approach:
ATEC is building a static E field pump for use in testing N in both gas
and liquid phase. NASA Goddard will supply a testing facility capable of
achieving operating temperatures between 20 and 80K with which to test the ATEC apparatus. NASA will also provide well skilled personnel to both help design and evaluate the results of the experiment and operate the apparatus.

posted 06-07-2002 02:29 PM            

Title: Advanced Multifunction RF System
Architecture Concepts
PI: Ron Kasparek
TRW INCORPORATED SPACE AND TECHNOLOGY
DIVISION
Space & Electronics Group
Address: One Space Park
Redondo Beach, CA 90278
(310) 813-5612
Funding Agency: Office of Naval Research
PR Number: 00PR05301-00
Award Number: N000140020005
Current End Date: 14-Apr-2002
Scientific Officer: Max Yoder

Objective:
This work seeks to parametrically investigate new component and
circuitry technologies with Navy electromagnetic system requirements
and provide the basis for new RF architectures, their projected life cycle costs, optimized insertion times, and impact on platform performance on 21st century Naval combatants.
Approach:
New component technologies such as ultra stable clocks, 100 GHz logic,
efficient, highpower, broadband, linear solid state microwave and
millimeter wave amplifiers will be parametrically compared in
architectures necessary for 21st century platform performance.
Multifunctional simultaneous signal capability with low radar cross
section are among the system performance objectives.

Title: Solid State vs. Tube Based Transmit RF
System Study
PI: Mike Fitelson
NORTHROP GRUMMAN CORPORTION
Electronic Sensors and Systems Group
Address: 7323 Aviation Blvd
Linthicum, MD 210900000
(410) 765-2547
Funding Agency: Office of Naval Research
PR Number: 00PR05311-00
Award Number: N0001400C0241
Current End Date: 31-Jul-2000
Scientific Officer: Max Yoder

Objective:
This work seeks to compare the relative merits of solid state vs. vacuum
tube technology for new systems and for modifications of old systems.
Approach:
A comparative analysis will be conducted using various functionality
parameters (e.g., EW, radar, Communications) vs. the projected
capabilities of vacuum tubes and wide bandgap solid state devices to
fulfill the performance needed for the various functionalities.

Title: New RF Architectures for AMRFS Effort
PI: William Mulqueen
LOCKHEED MARTIN GOVERNMENT ELECTRONIC
SYSTEMS
Government Electronic Systems
Address: P.O. Box 1027, 199 Borton Landing Road
Moorestown, NJ 080570927
(856) 722-2991
Funding Agency: Office of Naval Research
PR Number: 00PR05315-00
Award Number: N0001400C0210
Current End Date: 14-Apr-2002
Scientific Officer: Max Yoder

Objective:
This work seeks to parametrically investigate new component and
circuitry technologies with Navy electromagnetic system requirements
and provide the basis for new RF architectures, their projected life cycle costs, optimized insertion times, and impact on platform performance on 21st century Naval combatants.
Approach:
New component technologies such as ultra stable clocks, 100 GHz logic,
efficient, highpower, broadband, linear solid state microwave and
millimeter wave amplifiers will be parametrically compared in
architectures necessary for 21st century platform performance.
Multifunctional simultaneous signal capability with low radar cross
section are among the system performance objectives.

Title: High Performance MEMS Tunable Filters for
AMRFS
PI: Andrew Brown
M SQUARED TECHNOLOGIES LLC
Address: 305 N. Holbrook
Plymouth, MI 48170
(734) 647-1794
Funding Agency: Office of Naval Research
PR Number: 00PR05419-00
Award Number: N0001400C0235
Current End Date: 14-Jun-2001
Scientific Officer: John Zolper

Objective:
To investigate, design, build, and test novel tunable filters based on
MEMS switches and high-Q fixed capacitors.
Approach:
The approach is based on a novel "combinational" MEMS
switch/capacitor design that results in a wide tuning range with very
fine frequency control in a small physical space.

Title: Development of High Power, Wide Bandwidth
MMIC Amplifier Using AlGaN/GaN HEMT
Technology on Semi-insulating 4H-SiC
PI: Scott Sheppard
CREE INC
Address: 4600 Silicon Drive
Durham, NC 27703
(919) 361-5709
Funding Agency: Office of Naval Research
PR Number: 00PR05423-00
Award Number: N0001499C0172
Current End Date: 09-Sep-2002
Scientific Officer: John Zolper

Objective:
Demonstrate a 4-20 GHz power amplifier based on AlGaN/GaN
HEMTs for the AMRFS high band system.
Approach:
The contractor will advance the state-of-the-art high power
AlGaN/GaN HEMTs on semi-insulating 4H SiC substrates over the 4-20
GHz frequency range. This will involve studies of the optimum epitaxial
device structure and device configuration. Process modules (e.g.
through wafer vias) will be demonstrated to facilitate broad band
amplifier designs. Device reliability will be accessed at Cree and at NRL on parts supplied by Cree. Two circuit approaches will be examined
including reactively matched and a distribtured amplifier to maximize
power, gain, efficiency, and linearity (intermodulation) over the
frequency band.
Progress:
The contract was signed in 8 September 1999. The first device process
runs have been initiated and a kick-off meeting was held at the
contractors site.

Title: Development of High Power, Broadband SiC
MESFET MMICs
PI: Scott Allen
CREE INC
Address: 4022 Stirrup Creek Drive
Durham, NC 27713
(919) 361-5709
Funding Agency: Office of Naval Research
PR Number: 00PR05424-00
Award Number: N0001499C0173
Current End Date: 25-Aug-2002
Scientific Officer: John Zolper

Objective:
The contractor will develop SiC MESFET and MMIC technology for
the AMRFS 1-5 GHz transmit array.
Approach:
The contractor will demonstrate a hybrid 300 W SiC MESFET class B
push-pull power amplifier opeating over 1-5 GHz in accordance with the
AMRFS specifications for gain, efficiency, linearity, and physcial size.
Discrete SiC MESFETs will also be supplied to NRL for reliability testing.

Progress:
The contract was signed on 24 August 1999. A kick-off meeting was
held at the contractors site in October. The first transistor lots are
underway and circuit design has started.

Title: Fabrication and Properties of Free
Standing Nitride Semiconductor Films
Deposited by a Novel Low Temperature
PI: Jaime Freitas
NAVAL RESEARCH LABORATORY
CODE 6874
Address: 4555 OVERLOOK AVENUE S. W.
WASHINGTON, DC 203755347
(202) 404-4536
Funding Agency: Office of Naval Research
PR Number: 00PR05514-00
Award Number: N0001400RC20040
Current End Date: 30-Sep-2000
Scientific Officer: Colin Wood

Objective:
This NICOP collaborative program will optimize the electronic
properties of Group III nitride semiconductor films.
Approach:
Epitaxial GaN and other group III nitride films will be deposited by
plasma assisted and simultaneous optical energy assisted techniques.

Title: Measurement of the Electromagnetic
Compatibility of an Electrohydrodynamic
Pump with High Tc Squid Based Magnetic
PI: Ted Clem
COASTAL SYSTEMS STATION DAHLGREN
DIVISION
Dahlgren
Funding Agency: Office of Naval Research
PR Number: 00PR05551-00
Award Number: N0001400WR20276
Current End Date: 30-Sep-2000
Scientific Officer: Deborah Van Vechten

Objective:
The proven performance of SQUID gradiometers in finding buried mines
would be much more accessible for autonomous mine field mapping if
the packaging can be shrunk down until it closely approximates the size
of the sensor. Doing that requires a method of circulating refrigerant in narrow tubing that surrounds the sensor without introducing
interferring electromagnetic noise. The objective is to determine the magnitude of the problem when a macroscopic scale electro-hydro-dynamical pump is used.

Approach:
To take the inch scale EHD pump built for proving that liquid nitrogen can be pumped to the lab at Panama City Fl that has developed all the SQUID magnetic anomoly sensors. Noise spectral power curves will be taken as a function of EHD drive voltage levels and spatial separation and an estimate made of the minimum separation of the pump from the HTS sensors in a redesigned dewar if the EHD pump is providing the refri-gerant circulation.

Title: 100 GHz Low Phase Noise Clock Expansion
PI: Jerome Luine
TRW INCORPORATED SPACE AND TECHNOLOGY
DIVISION
Funding Agency: Office of Naval Research
PR Number: 00PR05576-01
Award Number: N000149820013
Current End Date: 31-Oct-2000
Scientific Officer: Deborah Van Vechten

Objective:
To establish the feasibility of and demonstrate a 100 GHz, low phase
noise clock integrated circuit which is based on superconducting SFQ
logic. The proposed circuit requires the achievement of coherent
oscillation of many Josephson junctions connected in parallel and the
maintenance of the signal purity through several subsequent circuit
functions. The most mature fabrication technology, Nb, will be used
along with custom InP output amplifiers developed for other programs
by TRW. The work will demonstrate a circuit that is generally useful for
high speed signal processing, including A/D and D/A, and in doing
digital true time delay beam steering. Both are needed by the Navy in
the context of ship self-defense and AMRFS.
Approach:
The approach will do circuit designs using SFQ logic, optimize the
designs by simulation, fabricate them in Nb technology, and test the
resultant chips. Each component of the circuit will be separately
designed, built, and tested before the combined circuit is attempted.

Title: High-Performance Waveform Generators for
Advanced Radar
PI: John Przybysz
NORTHROP GRUMMAN CORPORATION ELECTRONIC
SENSORS AND SYSTEMS DIVISION
Electronic Sensors and Systems Division
Address: 1745A WEST NURSERY RD
Linthicum, MD 210900000
(410) 765-7652
Funding Agency: Office of Naval Research
PR Number: 00PR05609-00
Award Number: N0001499C0632
Current End Date: 31-May-2001
Scientific Officer: Deborah Van Vechten
Objective:
To provide ship self defense, there is a strong technological need for
large spur free dynamic range, low phase noise waveform generators.
These capabilities will help find and identify small and stealthy targets and provide considerable enhancement to target detection in the
presence of clutter. This program will compare 4 technologies
potentially capable of delivering such signal generators and allow the
Navy a clear choice of the best technology for future advanced systems.
Approach:
The phase 1 program develops HBTs, transferred substrate HBTs, and
Josephson superconductive circuits for the purpose of demonstrating
the best spur free dynamic range (SFDR) and lowest phase noise. In
addition, GaAs MESFETs will be measured to provide COTS performance
comparisons. Northrop Grumman will also examine waveform generator
protocols to maximize overall system agility, including the generation of simultaneous beams with an array antenna.

Title: Support for IEEE/Cornell Conference August
7-9, 2000
PI: Gerald Witt
AIR FORCE OFFICE OF SCIENTIFIC RESEARCH
Physics & Electronics
Address: 801 North Randolph Street Rm 732
Arlington, VA 22203
(703) 696-8571
Funding Agency: Office of Naval Research
PR Number: 00PR05633-00
Award Number: N0001400MP20084
Current End Date: 30-Sep-2000
Scientific Officer: John Zolper

Objective:
Increase student participation in the Cornell Conference on High
Performance Devices.
Approach:
The funds will go to supporting student travel and registration fees for
the Cornell Conference on High Performance Devices. There will be
matching funds from AFOSR.

Title: Compact High Power Multiplexers for AMRFS
PI: Jeffrey Pond
NAVAL RESEARCH LABORATORY
Microwave Technology
Address: Code 6850
washington, DC 20375
(202) 767-2862
Funding Agency: Office of Naval Research
PR Number: 00PR06109-00
Award Number: N0001400WR20283
Current End Date: 30-Sep-2000
Scientific Officer: John Zolper

Objective:
To develop a compact, highpower filter for uses in a multiplexer or
channelizer.
Approach:
A Mobias strip resonator will be developed which will reduce the
resonator size by 4 times while maintaining highpower capabilitiy. This
is accomplished by taking advantage of the phase shift associated with a
resonator based on Mobias strip configuration. A 2-channel prototype
diplexer with 4-pole channel filters will be implemented in the first year.

Title: Developing Design Tools for the Fabrication
of RTD-Based Cellular Neural Networks
PI: Leon Chua
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA BERKELEY
Electrical Engineering & Computer
Science
Address: 336 Sproul Hall
Berkeley, CA 94720
(510) 642-3209
Funding Agency: Office of Naval Research
PR Number: 00PR06182-00
Award Number: N000140010507
Current End Date: 30-Apr-2001
Scientific Officer: Larry Cooper

Objective:
To develop simulation software which can be used by developers for
designing CNN circuits to be used in image processing applications.
Approach:
A SPICE based simulation program will be developed in which the RTD
device is implemented as the nonlinear element in the CNN cell design.
The SPICE parameters will be selected which allows for optimization of
the circuits. A template design module will be developed which can be
used for mapping retinal functions into the CNN simulations. Cell
designs will be explored for evaluation of the RTD-CNN as a potential
artificial retina.

Title: Real Time CNN Image Processing System for
Challenging Military Imaging Applications &
Implementation of Biocentric Algorithms
PI: Leon Chua
TERAOPS
Address: 1051 Cragmont Avenue
Berkeley, CA 94708
(510) 848-7652
Funding Agency: Office of Naval Research
PR Number: 00PR06183-00
Award Number: N0001400C0295
Current End Date: 31-Dec-2002
Scientific Officer: Larry Cooper

Objective:
To devise Cellular Nonlinear Network designs to implement retina
inspired algorithms for image processing applications, and to provide
hardware processors for testing.
Approach:
Computer hardware will be developed in which to demonstrate the CNN
algorithms for image processing based on digital computation. Retina
studies will provide such bio-inspired algorithms. This hardware will be
tested on platforms at China Lake. Based on these studies, key features
required of an analog CNN processor will be determined. These features
will be the basis for implementing complex spatio-temporal image
processing in such areas as image fusion, motion detection, and target
recognition. Key components for the analog circuitry will be designed,
fabricated and tested.

Title: International Specialist Meeting on Bulk
Nitride Growth and Related Techniques
PI: Shari Allwood
ALLWOOD AND ASSOCIATES INC
Address: 8279 Midland Rd
Mentor, OH 44060
(440) 951-1380
Funding Agency: Office of Naval Research
PR Number: 00PR06190-00
Award Number: N000140010505
Current End Date: 30-Apr-2001
Scientific Officer: Colin Wood

Objective:
To increase U.S. knowledge and expertise on bulk nitride substrate
preparation, and more rapid commercialization.

Title: Silicon Carbide Materials Research &
Technology Development
PI: Tangali Sudarshan
SOUTH CAROLINA RESEARCH INSTITUTE
College of Engineering
Address: Office of Research
Columbia, SC 29208
(803) 777-7302
Funding Agency: Office of Naval Research
PR Number: 00PR06243-00
Award Number: N000140010563
Current End Date: 31-Dec-2001
Scientific Officer: Colin Wood

Objective:
To determine and establish a sound technology for SiC crystal growth,
epitaxy and high voltage device fabrication.
Approach:
Modelling of growth and epitaxy environments will enable improved SiC
bulk crystal growth and wafering.

Title: 2000 Core Electronics Program Planning and
Assessment Review Support
PI: Charles Chamberlain
CACI TECHNOLOGIES INC
Address: 14151 Park Meadow Drive
(703) 679-3184
Funding Agency: Office of Naval Research
PR Number: 00PR06513-00
Award Number: N0001499D05180002
Current End Date: 30-Apr-2000
Scientific Officer: Ingham Mack

Objective:
Provide technical and management services to the ONR Electronics
Applied Research program.
Approach:
A Program Assessment and Planning Meeting will be held from
11-14 April 2000. The contractor will facilitate the review by providing a meeting space to accomodate a minumum of 50 people, prepare and
provide an evaluation book for each of 12 evaluators, summarize the
written comments and numerical scores from each evaluator, and
provide the results to ONR within ten days of the review. These results will have a very strong influence on the projects to be selected for FY 2001 funding.

Title: 2000 RF Requirements and S&T Opportunities
Workshops Support
PI: Charles Chamberlain
CACI TECHNOLOGIES INC
Address: 14151 Park Meadow Drive
(703) 679-3184
Funding Agency: Office of Naval Research
PR Number: 00PR06513-01
Award Number: N0001499D05180003
Current End Date: 14-Sep-2000
Scientific Officer: Ingham Mack

Objective:
Provide technical and management services to the ONR Electronics
Applied Research program.
Approach:
Two workshops will be held at NRL - one on 10-11 May and the other
on 25-27 July 2000. The contractor will facilitate the review by making
arrangements for the agendas, notifying invitees, maintaining a record
of presentations, and providing analysis and sorting of written and oral
material presented at the workshops. The results of the worhshops are
expected to l have a strong influence on the future of the ONR Vacuum/Solid State Electronics Applied Research Program.

Title: Modeling, Optimization, and Testing of Plse
Tube Refrigerators
PI: Ray Radebaough
U S DEPARTMENT OF COMMERCE NATIONAL
INSTITUTE OF STANDARDS AND TECHNOLOGY
Physical & Chemical Properties Division
M.S. 838.09
Address: 325 Broadway
Boulder, CO 80303
(303) 497-3710
Funding Agency: Office of Naval Research
PR Number: 00PR06541-00
Award Number: N0001400F0323
Current End Date: 30-Mar-2002
Scientific Officer: Deborah Van Vechten

Objective:
In order to win fleet acceptance of superconducting electronics, it is very necessary that it be packaged in such a way that the user need not be aware that the chips are operating at cryogenic temperatures and that
only electricity is added to the box to make the unit operational for
years at a time. This award will provide detailed state of the art
theoretical guidance to a fledgling vendor supported under an ONR
SBIR phase 2 as to whether and how pulse tube coolers can supply the Navy's needs for both small (electronics) and large (electric ship motor) systems at 4 and 10K temperatures using commercial refrigerator
compressors (cheap). If successful, these will be among the first pulse
tubes (no cold working parts, long MTFB) to operate at such low
temperatures and the only ones with an appropriate heat lift for
electronics. Single 10" high, rack mounted units are expected to result
from the combined effort, ca. a 10x volume reduction from current units.
Approach:
Consult heavily with pulse tube vendor (ART) regarding design details and measurements, do simulations of performance using NIST developed
software, measure laboratory demonstration units. Help define Navy
requirements and insure they will be met by final system designs.

Title: Fabrication and Properties of Free
Standing Nitride Semiconductor Films
Deposited by a Novel Low Temperature
PI: Jaime Freitas
NAVAL RESEARCH LABORATORY
CODE 6874
Address: 4555 OVERLOOK AVENUE S. W.
WASHINGTON, DC 203755347
(202) 404-4536
Funding Agency: Office of Naval Research
PR Number: 00PR06564-00
Award Number: N0001400WX21026
Current End Date: 30-Sep-2001
Scientific Officer: Colin Wood

Objective:
This NICOP collaborative program will optimize the electronic
properties of Group III nitride semiconductor films.
Approach:
Epitaxial GaN and other group III nitride films will be deposited by
plasma assisted and simultaneous optical energy assisted techniques.

Title: High Speed Magnetic Switching at Low Power
for Thin Film Magnetic Devices
PI: Jian-Gang Zhu
CARNEGIE MELLON UNIVERSITY
Department of Elec. & Comp. Eng.
Funding Agency: Office of Naval Research
PR Number: 00PR06704-00
Award Number: N000140010602
Current End Date: 30-Mar-2003
Scientific Officer: Larry Cooper

Objective:
To develop and apply computer simulation methods for describing high
speed switching processes in nanomagnetic structures being considered
for digital electronic applications.
Approach:
Numerical methods for describing the magnetization phenomena in thin
film magnetic structures will be extended to include dynamic switching
processes. The Landau-Lifshitz-Gilbert equations will be the basis for
calculating the magnetization of structures which include effects of size, shape, edge effects, exchange coupling, and materials parameters.
Various switching modes will be considered and the effects of energy
damping. The effect of spin polarized currents on switching speed will be modeled.

Title: Collaborative Investigations of IDFS for
Naval Applications
PI: Elie Baghdady
ADCOM SYSTEMS TECHNOLOGY INC
Address: ADCOM SYSTEMS TECHNOLOGY INC
PEABODY, MA 01960
(781) 899-5905
Funding Agency: Office of Naval Research
PR Number: 00PR06708-00
Award Number: N0001400M0147
Current End Date: 30-Dec-2000
Scientific Officer: Deborah Van Vechten
Objective:
To formulate an experimentally validated simulation model of the IDFS
concept and confirm that it has the properties claimed for it. If proven, this concept will enable a digital array to preferentially listen in specific directions independent of the number of interfering, in band signals coming from other directions. This capability will be very useful in securing the communications links on which CEC rests.
Approach:
The approach is to develop, in collaboration with Don Bowling, Navy
employee at NAWC, a MathCad simulation of the IDFS concept and define experiments for Mr Bowling to perform that will verify the simulation. The issues to be addressed include dechopping of unidirectional commutated, multiple signals and wideband signals, plus issues such as the relationship between data sample rate and the size of the angular acceptance cone around the desired signal and effect of IFDS on encoded signals and our ability to resolve them. The experimental work is to be done at NAWC-CL using existant government owned hardware. Four one week visits by Dr Baghdady are planned and frequent email communication will be used to exchange simulation programming, results, and discussions of technical issues.

Title: Superconducting Cable Design and Test
PI: Andrew Smith
TRW INCORPORATED SPACE AND TECHNOLOGY
DIVISION
Address: TRW Space & Electronics Group
Redondo Beach, ca 902780000
(310) 814-6792
Funding Agency: Office of Naval Research
PR Number: 00PR06713-00
Award Number: N0001400C0350
Current End Date: 30-Sep-2002
Scientific Officer: Deborah Van Vechten
Objective:
To supplement the materials development effort performed at Neocera
under an ONR SBIR phase 2 award and collaboratively develop a low
thermal and electrical loss ribbon cable for use with superconducting
components. For 4-10 K digital systems, these cables will be used to
transfer analog signals in and digital out with minimal heat load. For the 77K microwave community these cables will provide lower power
dissipation interconnects and allow co-located components such as
semiconductor LNA to self-bias to somewhat warmer temperatures. The
cables will be an enabling technology for superconducting electronics by
easing the fabrication of the required cryogenic packaging.
Approach:
The approach is provide technical guidance as to the design of ribbon
cables and testing of the thermal and microwave performance of
completed prototypes. TRW will also address the issue of end
connectors. Neocera, funded separately under 00pr06467-00, will focus
on the materials and fabrication technology development side of the
effort.

Title: Class D/E Delta-Sigma Switched Mode Power
Amplifiers
PI: Mark Rodwell
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA SANTA BARBARA
Department of Electrical and Computer
Engineering
Address: CHEADLE HALL ROOM 3227
Santa Barbara, CA 93106
(805) 893-3244
Funding Agency: Office of Naval Research
PR Number: 00PR06740-00
Award Number: N000140010653
Current End Date: 30-May-2003
Scientific Officer: John Zolper

Objective:
Develop a high power pulse mode amplifier at 5 GHz for amplification of
a digital pulse stream and subsequent integration to generate an
arbitrary analog waveform.
Approach:
A current controlled class D amplifier and/or class E amplifier will be
designed and built using AlGaN HEMTs to amplify digital pulse streams
for synthesis of analog wave forms up to 5 GHz.

Title: High Power Channelizer Filters
PI: Peter Petre
HRL LABORATORIES LLC
Address: 3011 Malibu Canyon Rd
Malibu, CA 90265
(310) 317-5919
Funding Agency: Office of Naval Research
PR Number: 00PR06811-00
Award Number: N0001400C0347
Current End Date: 30-May-2001
Scientific Officer: John Zolper

Objective:
Develop high power channelizer filters to cover the AMRFS bands of 1-5
GHz. Design a channelizer filter for 4-20 GHz.
Approach:
A 4-channel, highpower, channelizer will be developed to cover 1-5
GHz. A miniature version will also be designed that will meet the size
constraints of the AMRFS system. A 6-channel, high power channizer,
will also be designed to cover 4-20 GHz.

Title: Long Path VLF Diagnostics of Modified
D-Region for HAARP
PI: Umran Inan
THE BOARD OF TRUSTEES OF THE LELAND
STANFORD JUNIOR UNIVERSITY
Department of Electrical Eng./STAR
Laboratory
Address: 125 Panama Street
Stanford, CA 943054125
(415) 723-4994
Funding Agency: Office of Naval Research
PR Number: 00PR06815-00
Award Number: N000140010643
Current End Date: 28-Feb-2003
Scientific Officer: Edward Kennedy

Objective:
To develop a more detailed understanding of the relationship between
physical processes occurring in the ionosphere, particularly the
D-region, and the propagation of communication signals in the ELF/VLF
bands.
Approach:
The propagation of communication signals in the ELF/VLF frequency
ranges is by a waveguide mechanism in which the earth's surface serves
as one wall and the ionospheric D or E regions serve as the upper wall.
Variations in the structure of the ionospheric boundary can affect the
amplitude and phase of signals received at long ranges. The approach
of this effort will be to use a unique diagnostic tool developed to take
advantage of Navy comm signals in the VLF band to develop data relating
both naturally occurring as well as artificially induced ionospheric
variations to the quality and reliability of such signals using sophisticated algorithms that, in turn, can provide insight into
improvements to signal and equipment design.

Title: A Simulation and Experimental Program to
Enhance the Efficiency of ELF/VLF
Generation at HAARP
PI: Harvey Rowland
NAVAL RESEARCH LABORATORY
Plasma Physics Division
Address: ATTN CODE 3310
Washington, DC 203755320
(202) 767-6644
Funding Agency: Office of Naval Research
PR Number: 00PR06824-00
Award Number: N0001400WR20300
Current End Date: 30-Sep-2000
Scientific Officer: Edward Kennedy

Objective:
To evaluate potentially dramatic improvements to the generation of
ELF/VLF signals through ionospheric interactions. These techniques,
which have been developed and studied both theoretically and using
computer models, will be evaluated experimentally at the HAARP
ionospheric interaction facility.
Approach:
This effort will follow the general approach of selecting promising
theoretical techniques, evaluating the optimum method using previously
developed computer models and converting the technique into an
experimental program to be conducted at the HAARP ionospheric
interaction facility. Expected improvements to the generation of
ELF/VLF will be evaluated by comparison of experimental results with
computer predictions and revision of experimental plan if warranted.
The effort will verify the predicted signal quality improvements in a
methodical manner, selecting the most promising techniques initially
and modifying the experimetal plan as results are obtained.

Title: Application of and Enhancement to Arctic
Infrastructure for the Study of Long-Term
Change in the Earth's Polar Mesosphere
PI: Michael Kelley
CORNELL UNIVERSITY
Electrical Engineering
Address: Electrical Engineering Department
Ithaca, NY 14853
(607) 255-2944
Funding Agency: Office of Naval Research
PR Number: 00PR06878-00
Award Number: N000140010658
Current End Date: 30-Apr-2005
Scientific Officer: Edward Kennedy
Objective:
To expand Naval knowledge of the Arctic upper atmosphere and
mesosphere, two regions that have not been studied extensively,
particularly in the areas of electrical characteristics and the resulting impact on modern Naval communication and surveillance systems. The research will utilize and capitalize on the availability of sophisticated diagnostic instruments installed at the HAARP ionospheric observatory in Alaska.
Approach:
The research will employ instruments installed at the HAARP
Observatory to detect and characterize the existence of mesospheric
features as they are created, drift and dissipate over multiple seasons.
There is evidence that the frequency and geographical extent of these
structures are correlated with global change and may have an increasing
impact on electromagnetic systems operating in the Arctic. The effort
will use existing or planned radar systems operating over a wide variety
of frequency ranges in the study. Coordination with other Arctic
facilities will be maintained to optimize the research plan and promote
synergistic results. It may also be possible to combine the electro-magnetic studies using HAARP with in-situ sampling using rockets from the Poker Flat research range in Fairbanks.

posted 06-07-2002 02:30 PM            

Title: Direction of Arrival Dependent Signal
Modulation Through Time-Varying Array
Patterns: A Preliminary, Mathematical Study
PI: Jeffrey Coleman
NAVAL RESEARCH LABORATORY
Radar Division Code 5341
Address: 4555 Overlook Ave SW
Washington, DC 203755336
(703) 404-8843
Funding Agency: Office of Naval Research
PR Number: 00PR07061-00
Award Number: N0001400WR20311
Current End Date: 30-Sep-2000
Scientific Officer: Deborah Van Vechten
Objective:
Ten years ago E. Baghdady introduced the concept of inducing an angle
of arrival dependent Doppler frequency shift to allow signals in the same as-radiated frequency band to be separated in a receiver. The ability of such a system to cope with jamming signals would be revolutionary, but the difficulty in realizing the concept using analog hardware has contributed to the absence of proof of concept despite 2 SBIR phase 2 awards. This award will generalize the equations which describe the translation of signals from individual elements in an antenna array into a final combined signal to deal with construction of composite signals representing moving phase centers. Once these linear but time dependent schemes of signal processing have been defined, evaluation of the optimal manner of using them to reject in-band signals based on their angle of arrival should be possible.
Approach:
Investigate the potential of time varying arrays (elements and their
processing software) realizable through application of existing digital
signal processing approaches. In particular, define how to realize a time varying FIR filter in the case where the antenna elements are identical.

Title: III-V Nitride Heterojunction Bipolar
Transistors for Power Amplifiers
PI: Russell Dupuis
THE UNIVERSITY OF TEXAS AT AUSTIN
Microelectronics Research Center
Funding Agency: Office of Naval Research
PR Number: 00PR07066-00
Award Number: N000149910479
Current End Date: 26-May-2001
Scientific Officer: John Zolper

Objective:
To model and fabricate an AlGaN/GaN heterojunction bipolar transistor (HBT) for microwave power amplifiers.
Approach:
To develop a detailed Monte Carlo model of the performance of AlGaN HBTs based on realistic material and processing parameters. The modeling will be used to guide an experimental demonstration of AlGaN
HBTs for microwave power amplifiers.
Progress:
Progress has been made on growing and processing AlGaN HBTs and
GaN BJT. Of particular note has been work on controlling the Mg dopig
profile at the base/emitter junction. Functional DC HBTs have been
demonstrated but with low current gain. Issues related to contact
spiking and their role on junction leakage are being examined.

Title: Gordon Research Conference on Point and
Line Defects in Semiconductors
PI: Carlyle Storm
GORDON RESEARCH CONFERENCES
Director of Gordon Conferences
Funding Agency: Office of Naval Research
PR Number: 00PR07164-00
Award Number: N000140010676
Current End Date: 31-May-2001
Scientific Officer: Larry Cooper

Objective:
To discuss research results and directions in the study of point and line defects in semiconductors which will lead to improved performance of electronic devices.
Approach:
The Gordon Research Conference on Point and Line Defects in
semiconductors will be organized to provide a forum for discussing
results and issues on the properties and effects of defects and impurities in various semiconductor materials. Topics will include: defects in ZnO; diffusion of impurities in Si; defects in Si/Ge; defects in compound semiconductors; defects in devices; extended defects and interfaces.

Title: Electronic Structure & Interfaces of
Narrow-Gap (6.1-A) III-V Semiconductors
PI: Donald Wolford
IOWA STATE UNIVERSITY
Dept. of Physics & Astronomy &
Microelectronics Research Center
Address: 211 Beardshear Hall
Ames, IA 50011
(515) 294-5769
Funding Agency: Office of Naval Research
PR Number: 00PR07167-00
Award Number: N000140010675
Current End Date: 30-Nov-2001
Scientific Officer: Larry Cooper

Objective:
To develop understanding of the electronic properties of various
heterostructure materials in the narrow gap III-V semiconductors which
will be developed into low power electronic devices.
Approach:
Optical spectroscopies, using short pulse lasers, will be used to
investigate the bandstructure, transport and radiative properties of
heteroepitaxial structures based on various combinations of InAs, GaSb,
and AlSb semiconductors. Diamond anvil cells will be used to modulate
the band gap of these materials in order to map out bandstructure,
defect states, and recombination mechanisms. Band offsets will be
measured. A wide variety of band gap engineered structures will be
investigated to explore differences due in Type I and Type II
heterojunctions.

Title: Spin Effects in Mesoscopic Systems
PI: Aron Pinczuk
THE TRUSTEES OF COLUMBIA UNIVERSITY IN
THE CITY OF NEW YORK
Dept. of Applied Physics and Applied
Mathmatics
Funding Agency: Office of Naval Research
PR Number: 00PR07367-00
Award Number: N000140010714
Current End Date: 31-Dec-2000
Scientific Officer: Larry Cooper

Objective:
To provide a forum to discuss the latest research progress in the area of spin polarized electrons in nanoscale devices.
Approach:
An International Conference on Spin Effects in Mesoscopic Systems will
he held in Cortona, Italy on 29 Jun-2 Jul 2000. Topics which address
the issues and problems in understanding and controlling the spin
degree of freedom of electrons in nanoscale devices. Topics will include spin coherence in low dimensional semiconductors; spin polarized transport; spin electronics in quantum computation; Kondo effect in quantum dots; metal-insulator transition; ferromagnetic
heterostructures; optical spectroscopy of low dimensional structures.

Title: 7th International Workshop on Computational
Electronics (IWCE-7)
PI: John Barker
THE UNIVERSITY OF GLASGOW
Nanoelectronics Research Centre

Funding Agency: Office of Naval Research

PR Number: 00PR07371-00
Award Number: N000140010713
Current End Date: 31-Dec-2000
Scientific Officer: Larry Cooper

Objective:
To provide a forum to discuss the latest results in the development of
methods for simulations of semiconductor device performance which are
to be used in the design of electronic devices.
Approach:
An international workshop will be organized with invited speakers
presenting their results on methods and solutions to problems in device
simulations. Topics of interest include: simulation of doping effects in
MOSFETS; 3D simulations of ultrasmall MOSFETs; optoelectronic device
simulation; Monte Carlo particle modeling; quantum transport methods
and results.

Title: Nanoimprint for T-Gate MESFET MMICs
PI: Stephen Chou
THE TRUSTEES OF PRINCETON UNIVERSITY
Electrical Engineering Department
Address: E-Quad
Princeton, NJ 085445263
(612) 624-5599
Funding Agency: Office of Naval Research
PR Number: 00PR07384-00
Award Number: N000140010711
Current End Date: 30-Jun-2001
Scientific Officer: John Zolper

Objective:
Demonstrated fully functional GaAs MESFETs with sub 0.5 micron
T-gates fabricated with nano-imprint lithography. This will enable rapid throughput manufacturing of microwave circuits by replacing the time consuming (>4 hours per wafer) electron beam process presently used for gate definition.
Approach:
A single step, full wafer, nano-imprint lithography process will be
developed for realizing the proper photoresist profile to produce low
resistance T-gates for microwave transistors. A nano-imprint process for
low parasitic air bridge interconnects will also demonstrated. The work will be done in collaboration with Anadigics with functional circuits demonstrated at the end of the program.

Title: Development of Porous SiC Buffer Layers for
SiC Bulk and Epitaxial Growth
PI: Vladimir DMITRIEV
TECHNOLOGIES AND DEVICES INTERNATIONAL
INC
Address: 8660 DAKOTA DRIVE
GAITHERSBURG, MD 20877
(301) 208-8342
Funding Agency: Office of Naval Research
PR Number: 00PR07398-00
Award Number: N0001400C0428
Current End Date: 30-Sep-2001
Scientific Officer: Colin Wood
Approach:
Use of Epitaxial SiC films on porous substrates as reduced defect
density seeds for bulk SiC crystal growth.

Title: Depth Profiling Analysis of Thin
Semiconductor Films of SiC, Diamond, and
III-V Nitrides by Trace Element Accelerator
Mass Spectrometry
PI: Floyd McDaniel
UNIVERSITY OF NORTH TEXAS
Research and Grants
Address: Avenue C & Chestnut
Denton, TX 752655936
(940) 565-3251
Funding Agency: Office of Naval Research
PR Number: 00PR07409-00
Award Number: N000140010760
Current End Date: 14-May-2002
Scientific Officer: Colin Wood

Objective:
Identify and elimiate unwanted and deleterious electrically active
impurities in wide gap semiconductors.
Approach:
PI will use the very high resolution Mass spectrometer system at University of North Texas.

Title: Fabrication Technology for Vertical
Magnetoresistive Random Access Memory based
on Nanoimprint Lithography
PI: Jian Wang
NANONEX CORPORATION
Address: 7 Foulet Drive
Princeton, NJ 08450
(609) 683-3973
Funding Agency: Office of Naval Research
PR Number: 00PR07428-00
Award Number: N0001400C0399
Current End Date: 31-Jul-2002
Scientific Officer: Daniel Purdy
Objective:
Demostrate decreased size, increased speed, and increased density of
the Non-Volatile RAM using nano-imprint lithography technology.
Approach:
Implement a unique approach utilizing NIL to obtain 10 nm wide posts
within the device.

Title: Development of Multi-layer Films for Non
Volatile Magnetic Random Access Memory
(MRAM) Applications
PI: Patrick Taylor
UNIVERSITY OF IDAHO
College of Mines & Earth Sciences
Address: Dept. of Materials, Metallurgical,
Mining & Geological Engineering
Moscow, ID 838443024
(208) 885-6769
Funding Agency: Office of Naval Research
PR Number: 00PR07461-00
Award Number: N000140010735
Current End Date: 30-Sep-2001
Scientific Officer: Larry Cooper

Objective:
To establish facilities for the processing of magnetic device materials and to develop processing technologies for the fabrication of magnetic
memory elements.
Approach:
Various equipment will be purchased and installed including e-beam
lithography, plasma enhanced CVD deposition system, and sputtering
systems. GMR based metals will be deposited and processed for implementing a magnetic memory device in which current is transported perpendicular to the films. Electro-deposition, plasma etching and CVD methods will be developed and optimized. Materials will be characterized for magnetic and structural properties including Auger Emission Spectro-scopy to monitor impurity incorporation and STM/AFM to monitor structural properties of interfaces.

Title: Investigation of the Thermodynamic &
Kinetic Factors Involved in Synthesis of
III-N Thin Films
PI: Nathan Newman
ARIZONA STATE UNIVERSITY
Chemical Biological and Materials
Engineering
Funding Agency: Office of Naval Research
PR Number: 00PR07497-00
Award Number: N000140010783
Current End Date: 30-May-2001
Scientific Officer: Colin Wood

Objective:
To improve the understanding of the parameters limiting the growth
of thin films of GaN by molecular beam epitaxy.
Approach:
Reflection electron diffraction and desorption mass spectrometry will
be used to determine the kinetics, and energetics of MBE deposition
from activated nitrogen and group III elemental beams.
Progress:
A reactive III-N MBE growth/plasma-characterization system has
been successfully designed, assembled and fully-tested (7/98). The
system is able to synthesize III-N material with mono-energetic beams of
activated nitrogen at substrate temperatures as high as 1800 C.
Methods have been developed (1) to produce high-flux (>1015 cm-2s-1)
mono-energetic beams of atomic nitrogen (utilizing Penning ionization
in N2/noble gas plasmas) and (2) to tune the kinetic energy of high-flux
(>10^15 cm-2s-1) mono-energetic molecular nitrogen beams between 1
and 40 eV. In the upcoming year, kinetic and thermodynamic barriers
of III-N synthesis will be investigated under meta-stable growth
conditions. Growth of AlN under these ultra-high temperature conditions (>~1700 C) has been initiated to facilitate unprecedented growth rates and improved film quality.The thermochemistry of AlN Selective Energy Epitaxy was investigated using 1-50 eV activated-nitrogen beams and 1000-1400 C substrate temperatures. AlN films with <2 arc minute (0002) rocking curve widths are routinely synthesized using >30 eV kinetic energy and ~1075 C substrate temp. Higher temperatures (>1150 C) result in sticking coefficients (<0.05). In-situ anneals (1350 C) improve film quality, albeit with a moderate decomposition rate(~200 Angstroms/hr). The mosaic nature of the initial seed layer is optimized using elevated substrate temp. (>1150 C) and SiC substrates.

Title: Compound Semiconductor Roadmap for Defense
Electronics
PI: Gary Westling
COMPUTER SYSTEMS CENTER INC
Address: 6225 Brandon Ave
Springfield, VA 22150
(703) 866-4000
Funding Agency: Office of Naval Research
PR Number: 00PR07640-00
Award Number: N0001400A0001
Current End Date: 30-Jun-2003
Scientific Officer: Colin Wood

Objective:
Increase efficiency and application/direction of federal research funds in semiconductor electronics.
Approach:
Develop and maintain web site for national semiconductor research,
with help and input from all potential recipients of such funding.

Title: Advanced Fabrication Technology for
Nonvolatile Magnetic Memory
PI: Gary Prinz
NAVAL RESEARCH LABORATORY
Materials Science & Technology Branch
Funding Agency: Office of Naval Research
PR Number: 00PR07648-00
Award Number: N0001400WX21155
Current End Date: 30-Sep-2000
Scientific Officer: Larry Cooper
Objective:
To develop technologies for the wafer scale fabrication of VRAM elements
using lithography, deposition and etching processes.
Approach:
Deep UV contact printing will be developed at NRL in order to fabricate
0.2 micron scale VRAM devices. Electroplating techniques will be
developed to overcome the limitations to sputtering approaches.

Title: Switching-Mode Microwave Amplifiers for
Complex RF Signals
PI: Peter Asbeck
THE REGENTS OF THE UNIVERSITY OF
CALIFORNIA SAN DIEGO 0934
Department of Electrical Engineering
Address: 9500 GILMAN DRIVE
La Jolla, ca 920930407
(619) 534-6713
Funding Agency: Office of Naval Research
PR Number: 00PR07667-00
Award Number: N000140010784
Current End Date: 14-Jun-2002
Scientific Officer: John Zolper

Objective:
Develop high efficiency, high linearity pulse mode microwave amplifiers.
Approach:
Refine signal encoding algorithms for switching mode amplifiers with
complex rf signals to minimize digital noise generation. A low frequency(0.1 to 0.5 Ghz) class D amplifier will be demonstrated with complex signals using GaAs PHEMTS to validate the approach. In year two, higher power, 5 GHz pulse mode amplifiers will be demonstrated with
AlGaN HEMTs.

Title: High Temp Epitaxial Growth of Silicon
Carbide Layers & Structures
PI: Marek Skowronski
CARNEGIE MELLON UNIVERSITY
Dept. of Metallurgical Engineering
Funding Agency: Office of Naval Research
PR Number: 00PR07749-00
Award Number: N000140010786
Current End Date: 30-May-2001
Scientific Officer: Colin Wood

Objective:
Lower dislocation densities in Bulk and epitaxial Silicon Carbide.
Approach:
Build and commission a high temperature furnace system for growth on
porous SiC. The fulfilment of this program will depend upon DURIP
capital equipment grant for second growth furnace.

Title: Influence of Seed Preparation on the
Quality of SiC Bulk Grown Crystals
PI: Yuri Khlebnikov
BANDGAP TECHNOLOGIES INC
President
Address: 800 N Lucas ST Apt U7
West Columbia, SC 29169
(803) 794-3125
Funding Agency: Office of Naval Research
PR Number: 00PR07760-00
Award Number: N0001400C0441
Current End Date: 30-Jun-2001
Scientific Officer: Colin Wood

Objective:
Two order of magnitude reduction in SiC substrate threading dislocation
density.
Approach:
Porous SiC surfaces will be used as seed crystals for sublimation (PVT)
growth of bulk SiC crystal boules.

Title: High Temperature Epitaxial Growth of SIC
PI: Tangali Sudarshan
UNIVERSITY OF SOUTH CAROLINA
College of Engineering
Address: Office of Research
Columbia, SC 29208
(803) 777-7302
Funding Agency: Office of Naval Research
PR Number: 00PR07782-00
Award Number: N000140010812
Current End Date: 31-May-2001
Scientific Officer: Colin Wood

Objective:
To reduce the surface topography and improve purity of epitaxial SiC
semiconductor films.
Approach:
Modified heating elements and reactor design/control will be used to
allow 300 centigrade degree increase in operating temperature with
good temperature uniformity.

Title: Interfacing Magnetoelectronics with
Biochemistry Processes
PI: Jeffrey Byers
NAVAL RESEARCH LABORATORY
Materials Science and Technology
Address: NRL 6345
Washington, DC 203755320
(202) 767-6147
Funding Agency: Office of Naval Research
PR Number: 00PR07816-00
Award Number: N0001400WR20327
Current End Date: 30-Sep-2000
Scientific Officer: Larry Cooper

Objective:
To develop an AFM based nanolithographic process for organizing DNA
structures with nanomagnetic devices.
Approach:
The dip-pen method for controlling the assembly of DNA to a substrate
will be developed in which DNA strands will be tethered to magnetic
structures fabricated by nanolithographic processes.