Surface-acoustic-wave study of defects in GaAs grown by molecular-beam epitaxy at 220 degree C

Journal Article · Sat Feb 15 00:00:00 EST 1992 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.45.4258· OSTI ID:7282424

Khachaturyan, K; Weber, E R ^[1]; White, R M ^[2]

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1. Department of Materials Science and Mineral Engineering, University of California, Berkeley, California 94120 (United States) Materials Science Division, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States)
2. Berkeley Sensor Actuator Center, Electronics Research Laboratory, Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, California 94720 (United States)

Surface acoustic waves (SAW's) were used to study the influence of defects on the elastic properties of epitaxial films of semiconductors. The object of this study was As-rich GaAs grown by molecular-beam-epitaxy at 220 {degree}C. The SAW velocity on 0.3-wavelength-thick epilayers was 1.2% smaller than on the substrate alone. That velocity difference decreased after loss of some excess As as a result of 350 {degree}C--435 {degree}C anneals. A persistent increase as much as 0.4% of the SAW velocity at low temperatures was observed after illumination; this increase could be quenched by annealing at 120--130 K. This behavior is caused by the metastable transition of EL2-like As{sub Ga} defects and constitutes the direct experimental proof of the illumination-induced large lattice relaxation of this defect. The SAW velocity increase was correlated with the persistent bleaching of EL2-related optical absorption. The spectral dependence of rate of illumination-induced SAW velocity increase was measured.

• OSTI ID: 7282424
• Journal Information: Physical Review, B: Condensed Matter; (United States), Vol. 45:8; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
GALLIUM ARSENIDES
CRYSTAL DEFECTS
ANNEALING
MECHANICAL PROPERTIES
MOLECULAR BEAM EPITAXY
OPTICAL PROPERTIES
TEMPERATURE RANGE 0400-1000 K
ARSENIC COMPOUNDS
ARSENIDES
CRYSTAL STRUCTURE
EPITAXY
GALLIUM COMPOUNDS
HEAT TREATMENTS
PHYSICAL PROPERTIES
PNICTIDES
TEMPERATURE RANGE
360602* - Other Materials- Structure & Phase Studies