Electrical characterization of 60Co gamma radiation-exposed InAlN/GaN high electron mobility transistors

Abstract

In0.17Al0.83N/GaN high electron mobility transistors (HEMTs) were cumulatively subjected to 60Co gamma-ray irradiation doses up to 500 Mrad. Source–drain current–voltage characteristics (IDS-VDS) showed little change after lower dose gamma-ray irradiations (<200 Mrad). However, the electrical properties were significantly degraded after 500 Mrad irradiations, indicating that the radiation-induced damage near the active region of the devices was severe. The saturation current level at VGS = 0 V was degraded by 48% after 500 Mrad irradiation. The effective carrier removal rate was not linear with dose, but was 0.54 × 1010 cm−2 Mrad−1 in the range from 200 to 500 Mrad. The cumulative gamma-ray irradiation of In0.17Al0.83N/GaN HEMTs caused much larger reductions in drain–source current compared to AlGaN/GaN devices exposed under the same conditions.