Enhance Gate Reliability and Threshold Voltage Stability of p-GaN Gate High-Electron-Mobility Transistors

Gate reliability and threshold voltage instability issues were investigated in the enhancement-mode pGaN gate high-electron-mobility transistors (HEMTs). A n- GaN/p- GaN gate structure is proposed to effectively reduce the gate leakage and enlarge the gate swing of the p-GaN gate HEMTs. The VTH tunability and stability of the p-GaN gate HEMTs are also systematically investigated. With a p-FET bridge, wide range VTH can be achieved, as well as eliminated hole-deficiency-induced VTH shifts.