Stability of <i>V</i>_TH and <i>R</i>_ON in p‐GaN Schottky‐Gate AlGaN/GaN High‐Electron‐Mobility Transistors under Reverse and Gate Bias Stress: Impact of Gate Offset

Herein, the impact of the gate‐to‐p‐GaN offset on the performance of normally off p‐GaN Schottky‐gate AlGaN/GaN high‐electron‐mobility transistors under continuous reverse and gate bias stress is investigated for the first time. Devices with varying offsets are fabricated and analyzed. Large‐offset device features high threshold voltage ( V TH ), large subthreshold swing, low peak transconductance, and exhibits severe V TH instability under reverse bias stresses, demonstrating a weaker gate control. Besides, a negative V TH shift under gate bias stress is observed on large‐offset devices, which could be attributed to the increased hole accumulation at the offset region. Technology computer aided design simulations further verify this mechanism.