Native vacancies in Te-doped (5 x 1016 to 5 x 1015/cm3) material were investigated by using positron lifetime and Doppler-broadening coincidence spectroscopy. The experimental data were related to theoretical calculations of the positron lifetime and annihilation momentum distribution. Monovacancies were observed in all of the Te-doped samples. It was shown that they could be identified as being Ga-vacancy plus TeAs-donor complexes. These complexes were the predominant type of vacancy defect for the present doping range.

Microscopic Identification of Native Donor Ga-Vacancy Complexes in Te-Doped GaAs J.Gebauer, M.Lausmann, T.E.M.Staab, R.Krause-Rehberg, M.Hakala, M.J.Puska: Physical Review B, 1999, 60[3], 1464-7