R. Krauserehberg et al., EVIDENCE FOR A VACANCY-RELATED GROUND-STATE OF THE DX CENTER IN ALXGA1-XSB - A POSITRON-ANNIHILATION STUDY, Physical review. B, Condensed matter, 48(16), 1993, pp. 11723-11725
A vacancy-related defect center is observed by positron annihilation i
n AlxGa1-xSb (x = 0.5). This center appears at a concentration that is
equal to the DX-center concentration observed by deep-level transient
spectroscopy (DLTS). At low temperatures, the vacancy exhibits a meta
stable behavior after light illumination. The recovery kinetics of thi
s center agrees with the established properties of the DX center with
an activation energy of E(a) = (85 +/- 10) meV. In agreement with theo
retical predictions, it was concluded that the vacancy is part of the
ground state of the DX center. The results are in line with DLTS, the
Hall effect, and photoconductivity experiments.