Proton irradiation effects on buffer-free gallium nitride on silicon carbide high electron mobility transistor-based radio frequency power amplifier

Abstract

In this work, a comprehensive technology computer aided design-based investigation of a buffer-free high electron mobility transistor under proton radiation is presented. With a 37.55% thinner architecture (without thick and highly doped Fe buffer) grown on silicon carbide substrate, this device design improves the two-dimensional electron gas (2DEG) confinement and helps to eliminate the various dispersion effects and buffer leakage. To gain better insight into the buffer-free device architecture, direct current (DC), thermal, and radio frequency (RF) studies are carried out. To establish the various prospects of this device in high-power and space applications, the performance of the device under 1.8 MeV proton radiation environment is systematically studied. A comparison demonstrates that the buffer-free structure under proton radiation with fluence shows a current degradation of 18.68% compared with 72.7% in the case of conventional architecture. The excellent capability of the buffer-free device to confine 2DEG more precisely even under radiation environments can be concluded from the various DC and RF parameters studied. An extensive study of the effects of proton fluences and biases on the RF power amplifier figures of merit was also conducted by carrying out harmonic balance simulations for different radiation setups, which demonstrates excellent performance of the buffer-free structure.