Evidence for two energy levels associated with EL2 trap in GaAs

Abstract

By photocapacitance technique, applied to n-type LEC-grown GaAs, two energy levels:E v +0.45 eV andE c −0.75 eV are identified, for the first time, as being associated with the EL2 trap. As follows from the analysis of photo-EPR results on highly resistive GaAs crystals, the same energy levels can be attributed to the arsenic antisite defect, AsGA. In view of these findings, it is argued that the occupied EL2 level corresponds to the neutral charge state of AsGa defect.