Effect of proton irradiation energy on SiNx/AlGaN/GaN metal-insulator semiconductor high electron mobility transistors

Abstract

The effects of proton irradiation energy on the electrical properties of SiNx/AlGaN/GaN metal-insulator semiconductor high electron mobility transistors (MISHEMTs) using in situ grown silicon nitride as the gate dielectric were studied. The SiNx/AlGaN/GaN MISHEMT devices were irradiated with protons at energies of 5, 10, or 15 MeV at a fixed fluence of 2.5 x 10(14) cm(-2). The largest amount of device degradation was shown in the samples irradiated with the lowest irradiation energy of 5 MeV. The DC saturation current was reduced by 10.4%, 3.2%, and 0.5% for MISHEMTs irradiated with proton energies of 5, 10, and 15 MeV, respectively. Device performance degradation was more pronounced in the irradiated samples under high-frequency operation. At a frequency of 100 kHz, the percent saturation drain current reduction at a gate voltage of 3 V was 40%, 19%, and 17% after proton irradiation at 5, 10, and 15 MeV, respectively. The carrier removal rates for the MISHEMT devices were in the range of 21-144 cm(-1) for the proton irradiation energies studied. The measured DC degradation and carrier removal rates are lower than the values reported for AlGaN/GaN metal-gate high electron mobility transistor devices irradiated at similar conditions, which can be attributed to the SiNx insulating layer reducing the total damage on the AlGaN surface. Published by the AVS.