A Physically Analytical Hybrid Model for P-GaN/AlGaN/GaN HEMTs

A physically analytical hybrid model is proposed for p-GaN/AlGaN/GaN high electron mobility transistors (HEMTs) in this paper. The model is developed by analyzing the relationship between the 2-D electron gas and the potential drop across each layer. It considers the doping effects and physical mechanisms of the p-GaN gate, and combines them with the core drain current model from the Advanced SPICE Model for GaN devices (ASM-GaN) to derive the analytical equation for drain current. Furthermore, the nonlinear capacitance is characterized using a current-controlled current source, leading to an analytical function describing the relationship between the nonlinear capacitance and voltage. The model is implemented using Verilog-A and extract model parameters in ICCAP. Comparison between test data and simulated data demonstrates fitting curve errors of within 4% for DC characteristics and 0.6% for dynamic capacitance models, confirming the accuracy of the model.