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651.  Well Resolved Room Temperature Photovoltage Spectra of GaAs-GaInP Quantum Wells and Superlattices
Xiaoguang He and Manijeh Razeghi
Applied Physics Letters 62 (6)-- February 8, 1993
We report the first well resolved room‐temperature photovoltage spectra due to the sublevel transitions in the GaInP‐GaAs superlattices and multiquantum wells grown by low pressure metalorganic chemical vapor deposition. Sharp well resolved peaks attributed to exciton absorption of the electron‐to‐light hole and electron‐to‐heavy hole have been observed at room temperature. This indicates that GaAs‐GaInP is a promising material for the application of the modulators, optical switches, and optical bistable divices. Satisfactory agreements between experimental measurements and theoretical results have been obtained. These results demonstrate that photovoltage spectroscopy is a simple, but very powerful tool to study quantum confinement structures.   reprint
652.  Intermixing of GaInP/GaAs Multiple Quantum Wells
C. Francis, M.A. Bradley, P. Boucaud, F.H. Julien and M. Razeghi
Applied Physics Letters 62 (2)-- January 11, 1993
The intermixing of GaInP‐GaAs superlattices induced by a heat treatment is investigated as a function of the annealing temperature and duration. Photoluminescence experiments reveal a large red shift of the effective band gap of the annealed quantum wells thus indicating a dominant self‐diffusion of the group III atoms which is confirmed by secondary ion mass spectroscopic measurements. For long enough annealing durations, the red shift saturates and even decreases due to the competing slower self‐diffusion of the group V atoms. Experiments are well understood based on a simple diffusion model. reprint
653.  Finite-Size Scaling in the Dissipative Transport Regime Between Quantum Hall Plateaus
Razeghi M., S. Koch, R.J. Hang, K.V. Klitzing, K. Ploog
-- January 1, 1993
654.  Splitting of the Landau Level Coincidence: A Novel Phase Transition in Tilted Magnetic Fields
Razeghi M., S. Koch, R.J. Hang, K.V. Klitzing
-- January 1, 1993
655.  Growth of InSb/GaAs layers on YIG-coated GGG substrate
C. Jelen, S. Charriere, M. Razeghi, and V.J. Leppert
-- January 1, 1993
656.  High Power 0.98 μm GaInAs/GaAs/GaInP Multiple Quantum Well Laser
K. Mobarhan, M. Razeghi, G. Marquebielle and E. Vassilaki
Journal of Applied Physics 72 (9)-- November 1, 1992
We report the fabrication of high quality Ga0.8In0.2As/GaAs/Ga0.51In0.49P multiple quantum well laser emitting at 0.98 μm grown by low pressure metalorganic chemical vapor deposition. Continuous wave operation with output power of 500 mW per facet was achieved at room temperature for a broad area laser with 130 μm width and 300 μm cavity length. This is an unusually high value of output power for this wavelength laser in this material system. The differential quantum efficiency exceeded 75% with excellent homogeneity and uniformity. The characteristic temperature, T0 was in the range of 120–130 K. reprint
657.  High Quality InSb Epitaxial Film Grown by Low Pressure Metalorganic Chemical Vapor Deposition
Y.H. Choi, R. Sudharsanan, C. Besikci, E. Bigan, and M. Razeghi
-- November 1, 1992
658.  Optical Investigations of GaAs-GaInP Quantum Wells Grown on the GaAs, InP, and Si Substrates
H. Xiaoguang, M. Razeghi
Applied Physics Letters 61 (14)-- October 5, 1992
We report the first photoluminescence investigation of GaAs‐Ga0.51In0.49P lattice matched multiquantum wells grown by the low pressure metalorganic chemical vapor deposition simultaneously in the same run on GaAs, Si, and InP substrates. The sharp photoluminescence peaks indicate the high quality of the samples on three different substrates. The temperature dependence of the photoluminescence indicates that the intrinsic excitonic transitions dominate at low temperature and free‐carrier recombinations at room temperature. The photoluminescence peaks of the samples grown on Si and InP substrates shift about 15 meV from the corresponding peaks of the sample grown on the GaAs substrate. Two possible interpretations are provided for the observed energy shift. One is the diffusion of In along the dislocation threads from GaInP to GaAs and another is the localized strain induced by defects and In segregations. reprint
659.  Frontiers of Monolithic Integration of Semiconductor III-V Optoelectronic Devices with Si Technology
M. Razeghi, R. Sudharsanan, and J.C.C. Fan
-- August 1, 1992
660.  GaInAs/GaAs/GaInP Buried Ridge Structure Single Quantum Well Laser Emitting at 0.98 μm
K. Mobarhan, M. Razeghi and R. Blondeau
-- July 30, 1992
661.  Evaluation of the Band Offsets of GaAs-GaInP Multilayers by Electroreflectance
Razeghi M., D. Yang, J.W. Garland, Z. Zhang, D. Xue
SPIE Proceedings, Vol. 1676, pp. 130-- January 1, 1992
We report the first band offset measurement of GaAs/Ga0.51In0.49P multiquantum wells and superlattices by electrolyte electroreflectance spectroscopy. The conduction and valence band discontinuities (Delta) Ec equals 159 ± 4 meV and (Delta) Ev equals 388 ± 6 meV have been measured. The values found for the conduction band, heavy-hole and light-hole masses in the GaInP barriers and GaAs wells and for the split-off well mass are in excellent agreement with the literature. The intraband, intersubband transition energies, which are important for III - V infrared detection devices, also were directly measured. reprint
662.  Caracterisation optique des semiconducteurs III-V par ellipsometrie et reflectance differentielle spectroscopique
Acher O., Omnes F., Razeghi M., Drevillion B.
-- September 1, 1991
663.  Incorporation of Impurities in GaAs Grown by MOCVD
Razeghi M., and M.A. di Forte-Poisson
-- September 1, 1991
664.  Etude du dopage de type n et p des materiaux GaAs et GaInP
Omnes F., Defour M., Razeghi M.
-- September 1, 1991
665.  GaAs-GaInP Multipayers for High Performance Electronic Devices
Omnes F., and Razeghi M.
-- September 1, 1991
666.  A Review of the Band Offsets Measurements in the GaAs/Ga0.49In0.51P System
Omnes F., and Razeghi M.
-- September 1, 1991
667.  Optical Investigations of GaAs-GaInP Quantum Wells and Superlattices Grown by Metalorganic Chemical Vapor Deposition
Omnes F., and Razeghi M.
Applied Physics Letters 59 (9), p. 1034-- May 28, 1991
Recent experimental results on the photoluminescence and photoluminescence excitation of GaAs‐Ga0.51In0.49P lattice‐matched quantum wells and superlattices are discussed. The full width at half maximum of a 10‐period GaAs‐GaInP superlattice with Lz=90 Å and LB=100 Å is 4 meV at 4 K. The photoluminescence excitation exhibits very sharp peaks attributed to the electron to light‐hole and electron to heavy‐hole transitions. The GaInP‐GaAs interface suffers from memory effect of In, rather than P or As elements. reprint
668.  Defects in Organometallic Vapor-Phase Epitaxy-Grown GaInP Layers
Feng S.L., Bourgoin J.C., Omnes F., and Razeghi M.
Applied Physics Letters 59 (8), p. 941-- May 28, 1991
Non-intentionally doped metalorganic vapor‐phase epitaxy Ga1−x InxP layers, having an alloy composition (x = 0.49) corresponding to a lattice matched to GaAs, grown by metalorganic chemical vapor deposition, have been studied by capacitance‐voltage and deep-level transient spectroscopy techniques. They are found to exhibit a free‐carrier concentration at room temperature of the order of 1015 cm−3. Two electron traps have been detected. The first one, at 75 meV below the conduction band, is in small concentration (∼1013 cm−3) while the other, at about 0.9 eV and emitting electrons above room temperature, has a concentration in the range 1014–1015 cm−3. reprint
669.  InGaAs(P)/InP MQW Mixing by Zn Diffusion Ge and S Implantation for Optoelectronic Applications,
Julien F.H., Bradley M., Rao E.V.K., Razeghi M., Goldstein L.
-- November 30, 1990
670.  Defects in High Purity GaAs Grown by Low Pressure Metalorganic Chemical Vapor Deposition
Feng S.L., Bourgoin J.C., and Razeghi M.
-- November 30, 1990
671.  Recent Advances in MOCVD Growth of GaAs/GaInP System for OEICs Applications
Razeghi M.
-- November 30, 1990

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