Optically detected magnetic resonance, and magnetic circular dichroism of optical absorption, methods were used to investigate As antisite-related defects. Irradiation with 1MeV electrons at 4.2K produced the Ga vacancy and some new As antisite-related defects. Annealing was performed at 77K or above. At 77K, the isolated As antisite defect was detected when semi-insulating material was irradiated. At temperatures of between 200 and 300K, the Ga vacancy decayed. This decay was related to the formation of an anti-structure pair. A second annealing step was found, at about 520K, where the anti-structure pair decayed. It was found that EL2 was formed at that temperature in irradiated semi-insulating material. However, this EL2 formation was not related to the antistructure pair decay. Magneto-optical measurements were also used to demonstrate the metastability of the three As antisite-related defects.

F.K.Koschnick, K.Krambrock, M.Hesse, J.M.Spaeth: Applied Physics A, 1995, 60[6], 551-5