Investigation of EL2 defect in 10MeV electron irradiated undoped semi-insulating LEC GaAs

The induced defects and especially the EL2 defect in 10 MeV electron irradiated undoped semi-insulating (SI) LEC GaAs samples were investigated by using optical transient current spectroscopy (OTCS) technique. The results indicate that the density of EL2 defect of irradiated GaAs decreases and the density of EL6 defect increases at lower fluence levels. At higher fluences, an increase in density of the EL2 level was observed. However, the density of the EL6 was decreased. It is suggested that on lower fluences, 10 MeV electron irradiation causes the dissociation of the EL2 defect, and may be used to decrease the main donor level EL2 in SI-GaAs.