The 15th IEEE International Conference on Electron Devices and Solid-State Circuits (EDSSC)

520 / 2019-03-06 11:09:00

The origin of on-state stress degradation of T-gate AlGaN/GaN HEMTs: experimental and first-principles insights

GaN HEMT,defects,reliability

Plenary track > Device and Circuit Reliability

In this work, we investigate the on-state stress degradation of T-gate AlGaN/GaN high electron mobility transistors (HEMTs), which is critical to the application of AlGaN/GaN HEMTs in microwave power amplifiers. It is found that on-sate gate stress causes the negative shift of the threshold voltage (Vth) of the T-gate AlGaN/GaN HEMT. The negative shift of Vth is found to originate from the defect configuration evolution of oxygen from VGa-ON to ON-H and the associated charge redistribution in the GaN channel. Our results indicated that the strengthening of VGa-ON complex during the device-fabrication would be a good choice to improve the reliability of AlGaN/GaN HEMTs.