Threshold Voltage Shift Model for P-Gan Gate Enhancement Mode HEMT

In this paper, we based on the gate structure of p-GaN HEMT connected with Schottky diode and PIN diode and analyzed the threshold voltage shift mechanism under the influence of gate voltage. Based on the carrier transport mechanism, the electron injection current and hole injection current of the p-GaN layer is discussed and calculated, while the gate current model and threshold voltage shift model of the p-GaN HEMT are analyzed. The accuracy of the model is verified by comparing with the experimental data. The effects of p-GaN doping concentration, AlGaN barrier layer thickness and Al component on the gate current and VTH shift are discussed based on the model. By optimizing the device structure and process parameters, the gate current of HEMT can be reduced and the stability of VTH can be improved.