Current oscillations in semi-insulating GaAs associated with field-enhanced capture of electrons by the major deep donor EL2

Current oscillations thermally activated by the release of electrons from deep levels in undoped semi-insulating GaAs were observed for the first time. They were attributed to electric field-enhanced capture of electrons by the dominant deep donor EL2 (antisite AsGa defect). This enhanced capture is due to the configurational energy barrier of EL2, which is readily penetrated by hot electrons.