Effects of proton irradiation on dc characteristics of InAlN/GaN high electron mobility transistors

Abstract

The effects of proton irradiation on the dc characteristics of InAlN/GaN high electron mobility transistors were investigated. In this study we used 5 MeV protons with doses varying from 2 × 1011 to 2 × 1015 cm−2. The transfer resistance and contact resistivity suffered more degradation as compared to the sheet resistance. With irradiation at the highest dose of 2 × 1015 cm−2, both forward- and reverse-bias gate currents were increased after proton irradiation. A negative threshold-shift and reduction of the saturation drain current were also observed as a result of radiation-induced carrier scattering and carrier removal. Devices irradiated with doses of 2 × 1011 to 2 × 1015 cm−2 exhibited minimal degradation of the saturation drain current and extrinsic transconductance. These results show that InAlN/GaN high electron mobility transistors are attractive for space-based applications when high-energy proton fluxes are present.