| Rare-Earth Doped Gallium Nitride (GaN)- An Innovative Path Toward Area-scalable Solid-state High Energy Lasers Without Thermal Distortion |
Apr-2009 |
22 pages |
| Authors:
Michael Wraback; Mark Dubinskiy; ARMY RESEARCH LAB ADELPHI MD SENSORS AND ELECTRON DEVICES DIRECTORATE
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 | We have demonstrated, for the first time, in situ neodymium (Nd) doping of gallium nitride GaN by plasma-assisted molecular beam epitaxy (PA-MBE). The Nd doping is controlled by the GaN growth conditions and the Nd effusion cell temperature. The Rutherford backscattering spectroscopy (RBS) and secondary ion mass spectrometry (SIMS) data indicated Nd doping as high as 8 at. %, with no evidence of phase segregation identified by x-ray diffraction (XRD) ... |
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| A New Method for Growth and Analysis of Next-generation Infrared (IR) Detector Materials |
Mar-2009 |
20 pages |
| Authors:
John D Demaree; Stefan Svensson; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
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| This report describes the development of a new analysis and crystal growth method for next generation infrared materials, namely, dilute nitride III-V semiconductors, which may be used in future low-cost night vision systems. The key to this method is isotopic enrichment of nitrogen-15 during material growth via molecular beam epitaxy, which allows enhanced detection of nitrogen using resonant nuclear reaction analysis. We synthesized films of gallium arsenide nitride (GaAsN) using ... |
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| Chemistry and Physics of Analyte Identification in Integrated Nanosensors |
05-Feb-2009 |
21 pages |
| Authors:
Ivan K Schuller; William Trogler; CALIFORNIA UNIV SAN DIEGO LA JOLLA OFFICE OF CONTRACT AND GRANT ADMINISTRATION
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| This supplement was dedicated to the development and modeling of phthalocyanine based chemical sensors. We used Organic Molecular Beam Epitaxy (OMBE) to prepare phthalocyanine based sensors. We lithographically patterned special electrode configurations and mounted them on a universal commercial carrier chip thus facilitating manufacturability in actual field testable devices closer to reality. Two types of metallo-phthalocyanine (M-Pc) based sensors were prepared; Co-MPc films 12 monolayer thick and 3 different kinds ... |
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| Study of Residual Background Carriers in Midinfrared InAs/GaSb Superlattices for Uncooled Detector Operation (POSTPRINT) |
19-Feb-2008 |
5 pages |
| Authors:
H J Haugan; S Elhamri; F Szmulowicz; B Ullrich; G J Brown; W C Mitchel; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH MATERIALS AND MANUFACTURING DIRECTORATE
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| The midinfrared 7 ML InAs/8 ML GaSb superlattices (SLs) were grown by molecular beam epitaxy at growth temperatures between 370 and 430 deg C in order to study the intrinsic characteristic of background carriers. Grown SLs were all residual p type with carrier densities in the low 10(exp 11)/sq cm, and a minimum density of 1.8 x 10(exp 11)/sq cm was obtained from the SL grown at 400 deg C. ... |
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| Multifunctional Oxide Films for Advanced Multifunction RF Systems |
14 SEP 2007 |
33 pages |
| Authors:
Volker D. Heydemann; PENN STATE ELECTRO-OPTICS CENTER FREEPORT PA
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| The Electro-Optics Center of the Pennsylvania State University procured and established a custom-designed molecular beam epitaxy (MBE) system and commenced growth of oxide (TiO2, STO, BTO, BST and MgO) and III-nitride (AIN, GaN) thin films, The growth parameters and layer properties of these films were investigated by various in-situ and ex-situ characterization techniques under the aspect of developing a AIGaN HEMT epitaxy process, a BST varactor epitaxy process and aiding ... |
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| Observation and Study of Dislocation Etch Pits in Molecular Beam Epitaxy Grown Gallium Nitride With the Use of Phosphoric Acid and Molten Potassium Hydroxide |
JUN 2007 |
18 pages |
| Authors:
Fred Semendy; Unchul Lee; ARMY RESEARCH LAB ADELPHI MD
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| Defects continue to challenge the functionality and reliability gallium nitride (GaN)-based devices. GaN grown on sapphire by molecular beam epitaxy was investigated by wet etching in hot phosphoric acid (H3PO4) and molten potassium hydroxide (KOH). Hexagonally shaped etch pits were formed on the etched sample surfaces. Etched samples were characterized with the use of atomic force microscopy (AFM) and scanning electron microscopy (SEM) and SEM cathode luminescence (SEM-CL). AFM images ... |
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| Growth and Characterization of Low Density InAs/GaAs Quantum Dots for Quantum Information Processes |
12 MAY 2007 |
12 pages |
| Authors:
Won J. Choi; KOREA INST OF SCIENCE AND TECHNOLOGY SEOUL
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| The work demonstrated growth of low density QDs and optimized of growth parameters for low density In"Ga"As/GaAs QDs with enhanced molecular beam epitaxy "MEMBE". The work also included characterization of wetting layer in low density QDs with a macro-PL measurement and development of -PL measurement for a single QD spectroscopy at low temperature ~ 4 K. |
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| Optical and magnetic properties of Eu-doped GaN |
29 SEP 2006 |
4 pages |
| Authors:
J. Hite; G. T. Thaler; R. Khanna; C. R. Abernathy; S. J. Pearton; J. H. Park; A. J. Steckl; J. M. Zavada; FLORIDA UNIV GAINESVILLE DEPT OF MATERIALS SCIENCE AND ENGINEERING
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| GaN films were doped with Eu to a concentration of ~0.12 at. % during growth at 800 C by molecular beam epitaxy, with the Eu cell temperature held constant at 470 C. All samples were postannealed at 675 C. The films exhibited strong photoluminescence PL in the red 622 nm whose absolute intensity was a function of the Ga flux during growth, which ranged from 3.0 10 7 to 5.4 ... |
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| Molecular Beam Epitaxy on Aligned Carbon Nanotube Arrays for Nanoelectronic Applications |
26 AUG 2006 |
11 pages |
| Authors:
Jong C. Woo; SEOUL NATIONAL UNIV (REPUBLIC OF KOREA) SCHOOL OF PHYSICS
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| The result on molecular beam epitaxy of GaAs and AlGaAs using carbon nanotubes (CNTs) as a crystalline seed is reported. At the growth temperature T sub G >or= 600 C, GaAs wraps around CNTs forming wirelike configuration, while Al composites form dot-like formation. At T sub G < 550 C, both GaAs and AlGaAs form dot-like droplets along CNTs. Raman and XRD show the dots and wires of III-arsenide on ... |
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| The Relationship of Microscopic Material Characteristics & Physical Behavior of Quantum Dots |
25 AUG 2006 |
4 pages |
| Authors:
Shan Torng; Y-C Fang; L. Hsu; CHUNG-SHAN INST OF SCIENCE AND TECHNOLOGY TAO-YUAN (TAIWAN) MATERIAL AND ELECTRO-OPTICS DIV
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| This research collected and analyzed the composition, structure and microstructure information at microscopic scales for the self-organized InAs/GaAs quantum dots through development of proper characterization techniques. |
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| Stress-Engineered Quantum Dots for Multispectral Infra-Red Detector Arrays |
30 JUN 2006 |
9 pages |
| Authors:
A. Madhukar; A. Konkar; J. C. Campbell; Y. C. Chang; W. I. Wang; UNIVERSITY OF SOUTHERN CALIFORNIA LOS ANGELES DEPT OF MATERIALS SCIENCE AND ENGINEERING
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| During the above-noted period of this Final Technical Report, the following salient milestones were reached: (1) Introduced and demonstrated the concept of injecting electrons into the quantum dot (OD) active infra-red absorbing region from bracketing doped contact layers (to suppress unwanted dark current) leaving the QD region undoped; (2) Introduced and demonstrated the benefits of the concepts of (a) strain-relieving OD capping layers, (b) current blocking layers, and (c) lateral ... |
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| Oxide Films RF Applications |
JUN 2006 |
11 pages |
| Authors:
Marek Skowronski; P. Salvador; CARNEGIE-MELLON UNIV PITTSBURGH PA OFFICE OF SPONSORED RESEARCH
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| TiO2 films were grown using a reactive molecular beam epitaxy system equipped with high-temperature effusion cell for Ti and ozone. The growth mode, characterized in-situ by reflection high-energy electron diffraction (RHEED), as well as the phase assemblage, structural quality, and surface morphology, characterized ex-situ by X-ray diffraction and atomic force microscopy (AFM), depended on the choice of substrate, growth temperature, and ozone flux. Films deposited on (100) surfaces of SrTiO3, ... |
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| Growth and Characterization of Large Diameter CdNzTe Crystals |
MAY 2006 |
27 pages |
| Authors:
Pavel Hoeschl; CHARLES UNIV PRAGUE (CZECH REPUBLIC) INST OF PHYSICS
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| The report summarizes the activities during the whole contract period. Parts of the results were presented in Progress Reports No. 1 and 2 and will not be repeated in detail. The goal of the effort was aimed to test the middle-pressure setup after completion and modification. Several boules were grown, wafers with dimensions 10x10 sq mm were fabricated and delivered to NVESD. New wafers with dimensions 10x10 sq mm and ... |
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| Indium Gallium Nitride/Gallium Nitride (InGaN/GaN) Nanorods Superlattice (SL) |
29 MAR 2006 |
16 pages |
| Authors:
Tea W. Kang; DONGGUK UNIV SEOUL (KOREA)
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| The growth condition, electrical, and optical properties of GaN nanorods grown on Si(111) substrates are investigated. The GaN nanorods were grown with a different growth time by using rf-plasma assisted molecular-beam epitaxy. It is clearly demonstrated that the critical diameter for defects-free GaN nanorods is determined to be below ~140 nm under the N-rich condition. Magnesium-doped GaN nanorods were also grown with the same growth condition. Two emission lines corresponding ... |
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| A1GaAs/GaAs Heterostructure Solar Cells Grown by Molecular Beam Epitaxy |
14 FEB 2006 |
5 pages |
| Authors:
Suwaree Suraprapapich; Supachok Thainoi; Montri Sawadsaringkarn; Somsak Panyakeow; CHULALONGKORN UNIV BANGKOK (THAILAND) DEPT OF ELECTRICAL ENGINEERING
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| The contractor shall investigate the integration of quantum dots to the heterostructure of solar cells and the self alignment of quantum dots grown on high-index GaAs substrates for future nano-electronic device applications |
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| Molecular Beam Epitaxy Growth and Characterization of Mid-IR Type-II "W" Diode Lasers |
07-Jun-2005 |
7 pages |
| Authors:
C L Canedy; W W Bewley; G I Boishin; C S Kim; I Vurgaftman; M Kim; J R Meyer; L J Whitman; NAVAL RESEARCH LAB WASHINGTON DC OPTICAL SCIENCES DIV
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| Type II 'W' diodes designed for emission at the spectral line of methane (3.31 micrometer) when operated near 80 K were grown on a compact 2IT RIBER molecular beam epitaxy system. Photoluminescence and cross-sectional scanning tunneling microscopy were used as tools to improve the growth quality of these structures. The diodes exhibited very low housing thresholds at T=80 K (24-40 A/cm(2)), although further development will be required to enhance the ... |
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| Systematic Studies of Carbon Doping in High Quality GaN Grown by Molecular Beam Epitaxy |
DEC 2004 |
17 pages |
| Authors:
James S. Speck; CALIFORNIA UNIV SANTA BARBARA DEPT OF MATERIALS
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| For the final contract period September 1, 2003 - December 31, 2004, we have completed the following tasks: * Sucessfully incorporated carbon into all MBE-grown HEMTs (in conjunction with the DARPA Wide Bandgap Semiconductor program) and realized record power non-field-plated GaN HEMTs (for both MBE and MOCVD. * In collaboration with Prof. Steve Ringel's group at Ohio State (under ONR support), completed an initial study of deep level optical studies ... |
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| Etching Characteristics and Surface Analysis of Molecular Bean Epitaxy Grown P-Type Aluminum Gallium Nitride With Boron Trichloride/Chlorine Gases in Inductively Coupled Plasma (ICP) Dry Etching |
NOV 2004 |
21 pages |
| Authors:
Fred Semendy; Phillip Boyd; Unchul Lee; ARMY RESEARCH LAB ADELPHI MD SENSORS AND ELECTRON DEVICES DIRECTORATE
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| Dry etching of magnesium doped p-type aluminum gallium nitride grown by molecular beam epitaxy (MBE) has been carried for the first time by inductively coupled plasma (ICP) system via the boron trichloride/chlorine (BCl3/Cl2) gas system with variations in chuck power, ICP power, chlorine (Cl2) ratio in Cl2/BCl3 and process pressure. Processed samples were cleaned by standard techniques, depths were measured, and etching rates and selectivity were calculated. Surface morphology of ... |
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| Ohio State University Cooperative Research and Development Agreement (CRDA). Crystal Growth by Molecular Beam Epitaxy (MBE) and Characterization of Optoelectronic Devices |
OCT 2003 |
15 pages |
| Authors:
William J. Siskaninetz; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH SENSORS DIRECTORATE
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| This is the final report for the Ohio State University CRDA, Project Number CRDE9501. The objective of this research project was two-fold: (1) develop improved knowledge regarding (but not limited to) Molecular Beam Epitaxy (MBE) Crystal Growth and Characterization for application to optoelectronic and other devices; (2) make available government facilities and expertise to help the OSU Research Foundation perform research and testing requested by industrial firms and other governmental ... |
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| Controlled Nucleation and Growth in Semiconductor Epitaxy |
30 JUN 2003 |
15 pages |
| Authors:
Chia-Gee Wang; NANO DYNAMICS INC NEW YORK
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| During Phase 1 support two types of ultrasonic transducers were designed and fabricated. These transducers were utilized for ultrasonically assisted deposition of silicon under Molecular Beam Epitaxy (MBE). Epitaxial Si growth on (100) Si wafers has been observed at reduced substrate heater temperatures when accompanied by simultaneous ultrasonic agitation of the substrate during deposition. |
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| Large Area Si Substrates for InP Based Electronics and Optical Device Manufacturing |
18 JUN 2003 |
29 pages |
| Authors:
Peter Chow; SVT ASSOCIATES INC EDEN PRAIRIE MN
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| InP-based materials enable optoelectronic and high speed devices. InP structures are limited in a real size, which greatly adds to the cost of InP devices. Conversely, silicon wafers are an order of magnitude larger and less costly. This STTR program seeks to create device quality InP layers on silicon substrates. The lattice mismatch between Si and InP would normally create defects in the crystal and result in poor material quality. ... |
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| Control of Semiconductor Epitaxy by Application of an External Field |
11 JUN 2003 |
25 pages |
| Authors:
Debasis Sengupta; Dimitris Pavlidis; CFD RESEARCH CORP HUNTSVILLE AL
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| With the growing demand for reduction in size of semiconductor devices, understanding the chemistry and physics at the atomistic level is becoming an essential part of the design of devices based on electronic materials. One of the major challenges in this area is to obtain desired surface morphology of a thin film by controlling external parameters, such as temperature and pressure. The smoothness of a thin-film surface depends on the ... |
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| Molecular Beam Epitaxy of Nitrides: Theoretical Modeling and Process Simulation |
22 MAY 2003 |
74 pages |
| Authors:
Rama Venkat; NEVADA UNIV LAS VEGAS DEPT OF ELECTRICAL AND COMPUTER ENGINEERING
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| A rate equation approach is proposed based on physically sound surface processes to investigate the molecular beam epitaxy growth and doping of III-N using ammonia and EC plasma source. A surface-riding layer of Ga/In/Mg and ammonia or N plasma species with several associated physical and chemical processes is included in this model. In the case of ammonia, the simulated Ga incorporation rate as a function of ammonia pressure and substrate ... |
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| Nonthermionic Cathode Development |
OCT 2002 |
60 pages |
| Authors:
M. A. Hasan; NORTH CAROLINA UNIV AT CHARLOTTE DEPT OF ELECTRICAL ENGINEERING
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| This project focused on developing methods for fabrication of nonthermionic cold cathodes based on a lattice-matched material system consisting of a conducting substrate (source of electrons), a wide-bandgap semiconductor (conduction band closer to the vacuum level), and a low-work function material (to facilitate high emission of electrons). A material system fulfilling these requirements was found in indium phosphide (InP) as a substrate, cadmium sulfide (CdS) as the wide-bandgap semiconductor, and ... |
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| The Role of Nitrogen-Induced Localization and Defects in InGaAsN (2% N): Comparison of InGaAsN Grown by Molecular Beam Epitaxy and Metal-Organic Chemical Vapor Deposition |
JAN 2002 |
8 pages |
| Authors:
Steven R. Kurtz; A. A. Allerman; J. F. Klem; R. M. Sieg; C. H. Seager; SANDIA NATIONAL LABS ALBUQUERQUE NM
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| Nitrogen vibrational mode spectra, Hall mobilities, and minority carrier diffusion lengths are examined for InGaAsN (approx. 1.1 eV bandgap) grown by molecular beam epitaxy (MBE) and metal-organic chemical vapor deposition (MOCVD). Independent of growth technique, annealing promotes the formation of In-N bonding, and lateral carrier transport is limited by large scale (>> mean free path) material inhomogeneities. Comparing solar cell quantum efficiencies for devices grown by MBE and MOCVD, we ... |
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| High Luminescence Efficiency from GaAsN Layers Grown by MBE with RF Nitrogen Plasma Source |
JAN 2002 |
6 pages |
| Authors:
Victor M. Ustinov; Nikolai A. Cherkashin; Nikolai A. Bert; Andrei F. Tsatsul'nikov; Alexei R. Kovsh; RUSSIAN ACADEMY OF SCIENCES SAINT PETERSBURG IOFFE PHYSICAL-TECHNICAL INST
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| (In)GaAsN based heterostructures have been found to be promising candidates for the active region of 1.3 micron VCSELs. However (In)GaAsN bulk layers and quantum wells usually demonstrate lower photoluminescence intensity than their nitrogen-free analogues. Defects associated with lower temperature growth and N-related defects due to plasma cell operation and possible nonuniform distribution of nitrogen enhance the non-radiative recombination in N-contained layers. We studied the photoluminescence intensity of GaAsN layers as ... |
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| InAsN Grown by Plasma-Assisted Gas Source MBE |
JAN 2002 |
6 pages |
| Authors:
Ding-Kang Shih; Hao-Hsiung Lin; Tso-Yu Chu; T. R. Yang; NATIONAL TAIWAN UNIV TAIPEI
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| We report the structural, electrical and optical properties of bulk InAsN alloy with various nitrogen contents deposited on (100) InP substrates by using plasma-assisted gas source molecular beam epitaxy. It is found that the fundamental absorption edge of InAsN, as compared to that of InAs, shifts to higher energy due to Burstein-Moss effect. A dramatic increase of the electron effective mass in a nitrogen-containing III-V alloy is also observed from ... |
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| InP/InGaAs Heterojunction Bipolar Transistors Grown on Ge/P Co-implanted InP Substrates by Metal-Organic Molecular Bean Epitaxy |
2002 |
3 pages |
| Authors:
W. J. Sung; R. F. Kopf; D. J. Werder; C. T. Liu; Y. K. Chen; CALIFORNIA UNIV LOS ANGELES
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| InP/InGaAs Heterojunction Bipolar Transistors (HBTs) have demonstrated excellent high- frequency performance 1-4 and are widely used for optical fiber transmission 5-7. However; the current mesa HBT structure utilizes a very thick, highly doped n+InGaAs layer for the subcollector contact. This added mesa height makes multilevel interconnection processes more difficult, which impedes the capability of fabricating compact integrated circuits. In addition, rip has a much higher thermal conductivity than InGaAs, so ... |
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| Barrier Roughness Effects in Resonant Interband Tunnel Diodes |
15 DEC 2001 |
6 pages |
| Authors:
R. Magno; A. S. Bracker; B. R. Bennett; B. Z. Nosho; L. J. Whitman; NAVAL RESEARCH LAB WASHINGTON DC PLASMA PHYSICS DIV
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| Peak current densities of InAs/AlSb/GaSb/AlSb/InAs resonant interband tunneling diodes (RITD) grown by molecular beam epitaxy have been measured as a function of the growth temperature. The growth procedures were designed to produce nominally identical AlSb tunneling barriers. The variations observed in the peak current for positive bias are consistent with the barrier on the substrate side of the RITD becoming effectively thicker for diodes grown at high temperatures. Plan-view in ... |
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| Heteroepitaxy on Compliant Substrates for Vertical and Horizontal Integration of Multi-Functional Devices |
10 OCT 2001 |
49 pages |
| Authors:
G. L. Olson; J. A. Roth; T. J. de Lyon; J. E. Jensen; J. S. Speck; HRL LABS LLC MALIBU CA
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| This report presents the results of research on compliant substrate behavior in III-V semiconductors grown by molecular beam epitaxy (MBE) on thin (50-80A) InGaAs layers on GaAs, and in II-VI semiconductors (HgCdTe, CdTe, ZnTe) grown on thin Si(211) layers on Si(100). A comprehensive experimental study was conducted utilizing spectroscopic ellipsometry, transmission electron microscopy, and atomic force microscopy at various stages in the fabrication and processing of the compliant layers and ... |
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| Growth and Characterization of High Frequency Materials |
15 SEP 2001 |
19 pages |
| Authors:
R. E. Camley; Z. Celinski; COLORADO UNIV AT COLORADO SPRINGS DEPT OF PHYSICS
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| This instrumentation award had following objectives: (1) Obtain a sputtering deposition system (2) Upgrade a UHV system to a Molecular Beam Epitaxy system (3) Build new FMR (ferromagnetic resonance) systems (4) Upgrade BLS (Brillouin Light Scattering) system. All of these objectives have been accomplished. We purchase a sputtering system equipped with 5 guns and E-beam system. We upgraded deposition system to a single chamber MBE system. We built four FMR ... |
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| Advanced RHEED Instrumentation for the Analysis of the Initial Stages of MBE Quantum Dot Growth for Semiconductor Lasers |
10 AUG 2001 |
4 pages |
| Authors:
Luke F. Lester; NEW MEXICO UNIV ALBUQUERQUE CENTER FORHIGH TECHNOLOGY MATERIALS
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| The Staib Instruments EK-15-R RHEED System purchased on this DURIP grant has been mounted in the University of New Mexico's (UNM) Vacuum Generators VH80 MBE system and used extensively for RHEED studies during the growth of antimony-bearing semiconductors. The beam rocking feature in this unit has been critical in establishing the exact angle of incidence needed for clear observation of reconstruction patterns during the growth of bulk and digital alloy ... |
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| Optimum Er Concentration for In situ Doped GaN Visible |
06 AUG 2001 |
4 pages |
| Authors:
D. S. Lee; J. Heikenfeld; A. J. Steckl; U. Hommerich; J. T. Seo; A. Braud; J. Zavada; CINCINNATI UNIV OH NANOELECTRONICS LAB
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| GaN thin films have been doped with varying Er concentrations (0.01 -10 at.%) during molecular-beam- epitaxy growth. As expected, the visible and infrared (IR) emissions, from photoluminescence (PL) and electroluminescence (EL), are a strong function of Er concentration. We report on the determination of an optimum Er doping level for PL and EL intensity. Secondary ion mass spectroscopy and Rutherford backscattering measurements showed that the Er concentration in GaN increased ... |
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| Molecular Beam Epitaxy (MBE) of Quantum Devices |
JUN 2001 |
1 pages |
| Authors:
A. Y. Cho; D. L. Sivco; H. M. Ng; C. Gmachl; A. Tredicucci; LUCENT TECHNOLOGIES INC MURRAY HILL NJ
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| Evolution of RHEED Intensity in the Simulated Homoepitaxial Growth of GaAs(OOl) |
JUN 2001 |
4 pages |
| Authors:
M. Itoh; T. Ohno; OSAKA UNIV (JAPAN) DEPT OF PHYSICS
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| The influence of surface reconstruction on the homoepitaxial growth of GaAs 100 has been studied by the Monte Carlo simulations. In the model both Ga and As species are deposited onto a GaAs 001 - beta2(2x4) reconstructed surface simultaneously at T about 580 C as this corresponds to the ordinary growth condition of molecular beam epitaxy. The growth mechanism of the beta2(2 x 4) structure has been identified; also studied ... |
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| Surface Segregation in Epitaxy of III-V Compounds |
JUN 2001 |
4 pages |
| Authors:
S. Yu. Karpov; Yu. N. Marakov; SOFT-IMPACT LTD SAINT PETERSBURG (RUSSIA)
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| Surface segregation in III-V compound heterostrucures grown by Molecular Beam Epitaxy (MBE) and Metal-Organic Vapor Phase Epitaxy (MOVPE) is studied theorencally. The suggested model treats segregation as a transient process resulting in a delayed highly-volatile species incorporation into the crystal accompanied by its accumulation on the growth surface. Specific features of In segregation in InGaAs and InGaN are discussed with respect to control of the composition profile and efficiency of ... |
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| E-Beam Irradiation Effect on CdSe/ZnSe QDs Formation by MBE |
JUN 2001 |
5 pages |
| Authors:
V. I. Kozlovsky; Yu. G. Sadofyev; Ya. K. Skasyrsky; RUSSIAN ACADEMY OF SCIENCES MOSCOW (RUSSIA) LEBEDEV INST
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| The strong influence of th%e RHEED e-beam irradiation on formation of CdSe QDs by MBE has been found. Large difference in CL spectia between inside the e-beam trace and outside it was observed. Probably the e-beam stimulates the adatoms diffusion along the growth surface and or plays role of a catalyst of chemical reaction between Cd and Se. |
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| A Technique for Fabricating InGaAs/GaAs Nanotubes of Precisely Controlled Length |
JUN 2001 |
4 pages |
| Authors:
V. Ya. Prinz; A. V. Chehovskiy; V. V. Preobrazenski; B. R. Semyagin; RUSSIAN ACADEMY OF SCIENCES NOVOSIBIRSKINST OF SEMICONDUCTOR PHYSICS
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| Single-crystal nanotubes of precisely controlled length were produced on a (110) cleaved facet of heterostruture. The selective MBE growth of a strained InGaAs/GaAs snip and its subsequent self-rolling were used. The proposed technique is capable of ensuring good reproducibility of all sizes and exact positioning of nanotubes. |
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| Anion Incorporation in AlGaAsSb Alloys Grown by MBE |
JUN 2001 |
4 pages |
| Authors:
A. N. Semenov; V. A. Solov'ev; B. Ya. Mel'tser; V. S. Sorokin; S. V. Ivanov; RUSSIAN ACADEMY OF SCIENCES SAINT PETERSBURG IOFFE PHYSICAL-TECHNICAL INST
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| An influence of MBE growth parameters (substrate temperature, total group V flux, and As/Sb flux ratio) on a composition of Al(x)Ga(1-x)As(y)Sb(i-y) alloys (x = 0.5) as well as their structural quality have been studied in detail. Using these data, As and Sb incorporation coefficients have been calculated in two different ways. An effect of the unintentional Sb incorporation in InAs layers is also discussed. |
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| Nitrogen-Activated Phase Separation in InGaAsN/GaAs Heterostructures Grown by MBE |
JUN 2001 |
4 pages |
| Authors:
I. P. Soshnikov; N. N. Ledentsov; B. V. Volovik; A. Kovsh; N. A. Maleev; RUSSIAN ACADEMY OF SCIENCES SAINT PETERSBURG IOFFE PHYSICAL-TECHNICAL INST
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| InGaAsN insertions in a GaAs matrix grown by molecular beam epitaxy (MBE) demonstrate a pronounced effect of phase separation even at relatively low indium and nitrogen concentrations. Cross-section high-resolution transmission electron microscopy (TEM) images processed using a specially developed software demonstrated an effect of nitrogen decomnon of InAs-rich regions in the structures studied. Formation of ordered structures of compositional domains has been revealed in plan-view TEM images. |
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| X-ray Diffraction Study of CdSe/BeTe Nanostructures Grown by MBE with Stressor-Controlled Interfaces |
JUN 2001 |
3 pages |
| Authors:
R. N. Kyutt; T. V. Shubina; S. V. Sorokin; S. V. Ivanov; P. S. Kop'ev; RUSSIAN ACADEMY OF SCIENCES SAINT PETERSBURG IOFFE PHYSICAL-TECHNICAL INST
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| This report documents a detailed XRD study of the novel type-II CdSe/BeTe nanostructures formed by stressor-assisted self-formation. High sensitivity of the diffraction curves to interface types is revealed. The model developed for a sinmilation of rocking curves includes spontaneous formation of BeSe enriched interface formation when the smaller amount of CdTe FM stressor as compared to that corresponding to a maximum RHEED SSI is intentionally deposited. |
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| X-Ray Characterization of Quaternary Antimonide Materials for Mid-IR lasers |
08 FEB 2001 |
4 pages |
| Authors:
Luke F. Lester; NEW MEXICO UNIV ALBUQUERQUE CENTER FORHIGH TECHNOLOGY MATERIALS
|
| The new mid-IR PL/optical pumping setup has been invaluable in the study of GaInAsSb and AlInAsSb materials that are MBE grown on a GaSb substrate. A PL intensity plot vs. wavelength for GaInAsSb grown at the University of New Mexico is displayed on the last page of the report. This PL trace was generated using the equipment purchased with the grant money. We believe that new alloys constructed from AlInAsSb ... |
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| Process for Automated, Safe MBE Start and Flux Calibration |
FEB 2001 |
27 pages |
| Authors:
Stefan Svensson; ARMY RESEARCH LAB ADELPHI MD
|
| A command procedure has been developed for the U.S. Army Research Laboratory (ARL) molecular beam epitaxy (MBE) computer control system that allows a user to set up the system for an automated, unattended start each morning. The automated sequence consists of- 1. A system safety check to determine if cell ramping should be allowed. 2. A cell temperature ramp to an outgassing temperature. 3. An outgassing of cells. 4. A ... |
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| MBE Growth and Properties of GaN, InGaN and GaN/InGaN Quantum Well Structures for Laser Diode Applications |
24 JAN 2001 |
25 pages |
| Authors:
J. F. Schetzina; NORTH CAROLINA STATE UNIV AT RALEIGH
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| The program topic was changed to growth of III-V nitrides by MBE by mutual agreement with J. Zavada of ARO. Growth of III-V nitrides by molecular beam epitaxy (NIBE) has been studied using rf nitrogen plasma sources. Plasma sources from three different vendors have been tested. All three of the sources have been used to grow high quality GaN. However, the EPI rf source produces an optical emission spectrum that ... |
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| Procedure for Substrate Temperature Control Using the Pyrometer During MBE Growth |
OCT 2000 |
28 pages |
| Authors:
Stefan Svensson; ARMY RESEARCH LAB ADELPHI MD
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| Command procedures have been developed for the Army Research Laboratory molecular beam epitaxy (MBE) computer control system that allow a user to automatically outgas and desorb the oxide from substrates before growth, as well as set substrate temperatures based on pyrometer readings during growths. These procedures allow completely unattended growth of structures once suitable temperatures have been determined. |
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| Epitaxial Growth and Characterization of MnAs/Si(111) Nanoscale Magnetoelectronic Heterostructures |
23 JUN 2000 |
4 pages |
| Authors:
A. G. Banshchikov; R. V. Pisarev; A. A. Rzhevsky; N. S. Sokolov; Ahsan M. Nazmul; RUSSIAN ACADEMY OF SCIENCES SAINT PETERSBURG IOFFE PHYSICAL-TECHNICAL INST
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| Molecular beam epitaxy was used to grow thin (6-12 nm) ferromagnetic MnAs films on a Si(111) substrate. The characterization of the film structural and magnetic properties was carried out using X-ray. RHEED. AFM and magneto-optical methods. |
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| Photoluminescence Studies on InAs/InSb Nanostructures Grown by MBE |
23 JUN 2000 |
3 pages |
| Authors:
Ya V. Terent'ev; A. A. Toropov; B. Ya. Mel'tser; V. A. Solov'ev; S. V. Ivanov; RUSSIAN ACADEMY OF SCIENCES SAINT PETERSBURG IOFFE PHYSICAL-TECHNICAL INST
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| Band Alignment in ZnCdTe/ZnTe and ZnCdSe/ZnSe SQW Structures Grown on GaAs(100) by MBE |
23 JUN 2000 |
5 pages |
| Authors:
V. I. Kozlovsky; Yu. G. Sadofyev; V. G. Litvinov; RUSSIAN ACADEMY OF SCIENCES MOSCOW (RUSSIA) LEBEDEV INST
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| MBE-grown ZnTe/CdZnTe/ZnTe and ZnSe/ZnCdSe/ZnSe strained single quantum well (SQW) structures with non-doping layers were investigated by cathodoluminescence (CL) and deep level transient spectroscopy (DLTS). Obtained DLTS and CL results were used for the estimation of the conduction band offset parameter Qc. |
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| Optical Properties and Structure of Si/InAs/Si Layers Grown by MBE on Si Substrate |
23 JUN 2000 |
4 pages |
| Authors:
N. D. Zakharov; P. Werner; U. Goesele; V. M. Ustinov; G. E. Cirlin; RUSSIAN ACADEMY OF SCIENCES SAINT PETERSBURG IOFFE PHYSICAL-TECHNICAL INST
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| Epitaxial Si/InAs/Si heterostructure grown on (001) Si substrate by molecular beam epitaxy (MBE) and annealed at 8OO degrees C was investigated by High Resolution Transmission Electron Microscopy (HRTEM). Extensive interdiffusion leads to the formation of an InAs solid solution in the Si cap layer. Additionally, InAs-enriched regions with extensions of 6mm, which exhibit two kinds of ordering are observed. The ordering of InAs molecules has occurred. The sample show photoluminescence ... |
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| MBE Grown Ge Nanostructures on CaF(2)/Si(111) |
23 JUN 2000 |
3 pages |
| Authors:
O. P. Pchelyakov; L. V. Sokolov; M. M. Moisseeva; N. S. Sokolov; RUSSIAN ACADEMY OF SCIENCES NOVOSIBIRSKINST OF SEMICONDUCTOR PHYSICS
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| Germanium nanocrystals were grown on CaF(2)/Si( 111) by molecular beam epitaxy. Specific features of Ge and CaF(2) growth have been analyzed in this work using electron diffraction and atomic force microscopy Well-pronounced Ge quantum dots were observed in case of growth on thick CaF(2) buffer. |
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Reports by Keyword(s)
*MOLECULAR BEAM EPITAXY
