Nature of compensating luminescence centers in Te-diffused and -doped GaSb

Abstract

Diffusion of tellurium in undoped p-GaSb has been carried out. Using the cathodoluminescence and photoluminescence techniques, the luminescence centers in Te-diffused samples have been identified and compared with the Te-doped bulk GaSb. Fundamental differences in the radiative levels are observed between the diffused and the as-grown doped samples. Evidence for self-compensating acceptor complexes are seen in diffused samples. With short and moderate diffusion times, a compensating acceptor complex VGaGaSbTeSb is observed. For long diffusion times, the dominant acceptor center has been attributed to the antisite defect GaSb or related complex. The reasons for the formation of various acceptor centers have been discussed.