Effects of strain and local charge on the formation of deep defects in III-V ternary alloys

The effects of external and internal strains and of defect charges on the formation of gallium vacancies and arsenic antisites in GaAs and In0.5Ga0.5As have been investigated by ab initio density functional methods. Present results show that a proper understanding of strain and defect charge permits the development of a defect engineering of semiconductors. Specifically, they predict that arsenic antisites in InGaAs ternary alloys can form, upon p-type doping in the presence of an arsenic overpressure, even in the case of high-temperature epitaxial growths.