Analysis of VTH Degradation and Recovery Behaviors of p-GaN Gate HEMTs Under Forward Gate Bias

In this work, detailed
${V}_{\text {TH}}$
degradation and recovery behaviors of p-GaN gate high electron mobility transistors (HEMTs) are studied under forward gate bias and elevated temperatures. Based on multiple time-evolving stress/recovery experiments, the abrupt negative
$\Delta {V}_{\text {TH}}$
behavior at initial recovery time at low
${V}_{\text {GS}}$
level as well as the suppressed
${V}_{\text {TH}}$
shift at high temperature have been observed. It is experimentally found that trapped electrons are more rapid-recoverable than the holes, and the carrier trapping effect is mitigated due to the strengthened carrier emission and recombination process across the AlGaN barrier at elevated temperatures. The ON-resistance (
${R}_{ \mathrm{\scriptscriptstyle ON}}{)}$
degradation behavior is also investigated within the same experiment, and the trapped holes at the passivation/AlGaN interface result in a decrease in
${R}_{ \mathrm{\scriptscriptstyle ON}}$
.