Threshold Voltage Instability After Double Pulse Test Under Different OFF-State Drain Voltages and ON-State Drain Currents in p-GaN Gate AlGaN/GaN HEMT

This study investigated threshold voltage (VTH) instability in a Schottky p-GaN gate AlGaN/GaN high-electron-mobility transistor (HEMT) by using the double pulse test (DPT) with a 1-µs pulse width in the ON-state and OFF-state. OFF-state drain biases (VDS,OFF) of 100–400 V and ON-state drain currents of ID,ON 1–16 A were applied in the DPT to observe the post-DPT VTH shift. The ON-state currents did not strongly influence the device's characteristics after the DPT. However, the OFF-state voltages, particularly VDS,OFF = 100 and 200 V, exerted notable effects. A TCAD simulation was conducted to investigate the mechanism underlying the VTH shift after the DPT at various VDS,OFF and ID,ON levels.