Electron-paramagnetic-resonance study of the isolated arsenic antisite in electron irradiated GaAs and its relation to the EL2 center

Arsenic antisites produced in GaAs by room‐temperature electron irradiation (RTEI) are examined by electron paramagnetic resonance (EPR). For the first time, this RTEI antisite, which has been believed to be the isolated antisite, is found to be metastable. The most efficient photon energy for photoquenching is found to be approximately 1.15 eV, which is very close to that observed for the well‐known EL2 center in undoped semi‐insulating GaAs. However, the thermal recovery temperature is about 200–250 K, much higher than that for the EL2 center.