10 MeV proton damage in beta-Ga2O3 Schottky rectifiers

Abstract

The electrical performance of vertical geometry Ga2O3 rectifiers was measured before and after 10MeV proton irradiation at a fixed fluence of 10(14) cm(-2), as well as subsequent annealing up to 450 degrees C. Point defects introduced by the proton damage create trap states that reduce the carrier concentration in the Ga2O3, with a carrier removal rate of 235.7cm(-1) for protons of this energy. The carrier removal rates under these conditions are comparable to GaN-based films and heterostructures. Even annealing at 300 degrees C produces a recovery of approximately half of the carriers in the Ga2O3, while annealing at 450 degrees C almost restores the reverse breakdown voltage. The on/off ratio of the rectifiers was severely degraded by proton damage and this was only partially recovered by 450 degrees C annealing. The minority carrier diffusion length decreased from similar to 340 nm in the starting material to similar to 315 nm after the proton irradiation. The reverse recovery characteristics showed little change with values in the range 20-30 ns before and after proton irradiation. Published by the AVS.