Co-60 Gamma Ray Damage in Homoepitaxial beta-Ga2O3 Schottky Rectifiers

Abstract

beta-Ga2O3 Schottky rectifiers consisting of thick (10 mu m) epitaxial drift regions on conducting substrates are shown to have a high tolerance to Co-60 gamma ray irradiation. This is due to the low carrier removal rate of <1 cm(-1) for gamma rays, which contrasts to values of 300-500 cm(-1) for MeV protons and alpha particles in the same rectifier structures. Changes in diode ideality factor, Schottky barrier height, on-resistance, on-off ratio, and reverse recovery time are all minimal for fluences up to 2 x 10(16) cm(-2) (absorbed dose of 100 kGy (Si)). These results are consistent with previous reports on gamma-irradiation of Ga2O3 metal oxide semiconductor field effect transistors (MOSFETs) where changes were ascribed to damage in the gate dielectric and not to the Ga2O3 itself. (c) The Author(s) 2019. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License.