INFRARED QUENCHING AND THERMAL RECOVERY OF THERMALLY STIMULATED CURRENT SPECTRA IN GAAS

Thermally stimulated current (TSC) spectra stimulated by infrared (hv less-than-or-equal-to 1.12 eV) light at 90 K have been used to study the photoquenching and thermal recovery of several dominant TSC peaks in Ga-rich, semi-insulating GaAs. The filling-pulse-length dependence of the quenching for these traps, and the temperature dependence of their recovery are clearly identified with the ground-to-metastable state transition of EL2. The data are consistent with the traps having a direct association with EL2 or EL2* rather than an indirect association which could result from a change in the dominant-free carriers as EL2 transforms to EL2*. If so, they likely are various point defects or impurities complexed with the arsenic antisite.