Metastable transformation of EL2 in semi-insulating GaAs: The role of the actuator level and the photoionization of EL2

Abstract

The metastable transformation of EL2 is modeled in terms of an additional acceptor level, whose role is the activation of the metastable transformation of EL2. This level, called the actuator of the metastability, enables the metastable transformation after capturing a hole. Thermal emission of this hole at 80–85 K renders the metastable transformation of EL2 quite ineffective above this temperature. The double acceptor 78/203 meV is proposed as a possible actuator.