Improvement of $V_{rm th}$ Instability in Normally-Off GaN MIS-HEMTs Employing ${rm PEALD}hbox{-}{rm SiN}_{rm x}$ as an Interfacial Layer

摘要

In this letter, reduction of threshold voltage instability in gate recessed normally-off GaN metal insulator semiconductor high electron mobility transistors with ${rm SiN}_{rm x}$ gate insulator was investigated. A plasma enhanced atomic layer deposition technique was successfully employed for very thin ${rm SiN}_{rm x}$ (5 nm) as an interfacial layer. The hysteresis and drift of threshold voltage in transfer curve and the forward biased gate leakage current were effectively reduced.