Effect of plastic deformation on electronic properties of GaAs

Abstract

A systematic study of plastically deformed (in compression) GaAs was carried out employing deep-level spectroscopies, optical absorption, and electronic transport measurements. Deformation-induced changes in the free-carrier concentration, the mobility, and occupation of deep levels were associated with a deep acceptor defect. Changes of the optical absorption in deformed samples were found to be due to a localized stress field of dislocations rather than transitions via localized levels. No evidence was found of any meaningful increase (>2×1015 cm−3) of the concentration of EL2 or other midgap donors for deformation up to about 3%. Thus, it is evident that the enhancement of the electron paramagnetic resonance signal of the arsenic antisite AsGa in deformed semi-insulating GaAs must be due to the increased ionization of AsGa rather than the generation of new antisite defects.