Impact of high temperature reverse bias (HTRB) stress on the degradation of AlGaN/GaN HEMTs

High temperature reverse bias (HTRB) stress experiments were carried out on industrial GaN HEMTs. Several degradation characteristics of DC parameters such as drain current degradation, transconductance reduction, and threshold voltage shift were identified. It was interesting that the devices showed a considerable decrease in gate leakage current after HTRB stress. The results showed that conventional trapped-electron related mechanisms failed to explain current degradation in the devices, while the current degradation may be related to surface pitting.