STRUCTURE AND STABILITY OF THE DX-CENTERS IN GAAS AND INP

Abstract

We review some of the recent theoretical studies on the atomic structure, the stability, and the vibrational modes of donor-induced defect levels in GaAs and InP. For Si and S donors, the microscopic origin of the DX center is investigated and a review is given of the shallow-to-deep DX level transition under hydrostatic pressure. We also discuss the band structure and the chemical bonding effects on the stability of donor impurities, which are associated with broken-bond and breathing-mode lattice relaxations.