Excellent Stability of GaN-on-Si High Electron Mobility Transistors with 5 µm Gate–Drain Spacing Tested in Off-State at a Record Drain Voltage of 200 V and 200 °C

AlGaN/GaN high electron mobility transistors (HEMTs) were electrically stressed in pinch-off condition at a drain voltage up to 200 V for 200 h at an ambient temperature of 200 °C. The tested transistors which were grown and processed on 4-in. silicon substrate showed negligible degradation. This proves that a combination of a high quality AlGaN/GaN/AlGaN double heterostructure, the in-situ Si3N4 deposition technique and an accurately optimized gate technology result in excellent device stability under harsh conditions.