Influence of traps on the gate reverse characteristics of normally-off high-electron-mobility transistors with regrown p-GaN gate

The influence of traps on the reverse gate leakage has been studied for two kinds of normally-off high-electron-mobility transistors with regrown p-GaN gate. Different acceptor traps in the p-GaN/AlGaN/GaN junction dramatically impact carrier behaviors, affecting the leakage mechanisms. The reverse gate current of the normal devices with a low density of traps which located at EV + 0.6 eV is dominated by Poole–Frenkel process. For the abnormal devices, a high density of new traps have been confirmed with an energy level of ∼0.8 eV, resulting in a trap-assisted tunneling thus a relatively high reverse gate leakage.