Analysis of Instability Behavior and Mechanism of E-Mode GaN Power HEMT with p-GaN Gate under Off-State Gate Bias Stress

In this study, we investigate the degradation characteristics of E-mode GaN High Electron Mobility Transistors (HEMTs) with a p-GaN gate by designed pulsed and prolonged negative (VGS) bias stress. Device transfer transconductance, output, gate-leakage were studied in detail, before after each VGS We found that gradual electrical parameters, such as threshold voltage (VTH) shift, on-state resistance (RDS-ON) increase, transconductance max (Gm, max) decrease, leakage current (IGS-Leakage) is caused stress time evolution magnitude voltage. The significance electron trapping effects was revealed from VTH shift or instability other parameter under different voltages. mechanism behind DC could be assigned to formation hole deficiency at region process p-GaN/AlGaN hetero-interface, which induces change electric potential distribution region. design application power devices still need reliability investigation for significant credibility.