Defects with deep levels in GaAs induced by plastic deformation and electron irradiation

• Published in: Japanese Journal of Applied Physics Vol. 27; no. 10; pp. 1929 - 1936
• Main Authors: HAGA, T, SUEZAWA, M, SUMINO, K
• Format: Journal Article
• Language: English
• Published: Tokyo Japanese journal of applied physics 01.10.1988
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electron states; Exact sciences and technology; Impurity and defect levels; Physics; Complex defect; Temperature; Heat treatment; Semiconductor materials; Defect level; Infrared absorption; Plastic deformation; Experimental study; Inorganic compound; Gallium Arsenides; Radiation dose; Electronic structure; Irradiation; Electrons; Deep level
• ISSN: 0021-4922; 1347-4065
• DOI: 10.1143/JJAP.27.1929

Defects with deep electronic energy levels induced by plastic deformation at 450degC or electron irradiation at room temperature in boat-grown GaAs crystals are investigated by means of optical absorption. The optical absorption spectra associated with the induced defects are compared with that of grown-in defects EL2. Thermal stabilities of the defects are studied by tracing the changes in the absorption spectra due to isochronal annealing of the specimens. The defects induced by the above two procedures are identified not to be EL2, even though some part of the defects gives rise to absorption similar to that caused by EL2 in the spectral shape. The absorptions in both the deformed and the irradiated samples are mostly photo-unquenchable. Deformation-induced defects responsible for this absorption are found to be As Ga antisite-related defects which are less thermally stable than EL2. Irradiation-induced defects giving rise to this kind of absorption are far more unstable in comparison with the deformation-induced defects, and are mostly eliminated by annealing at temperatures lower than 300degC.