We propose a surface potential (SP)-based compact model of p-GaN gate high electron mobility transistors (HEMTs) which solves the Poisson equation. The model includes all possible charges in the GaN channel layer, including the unintended Mg doping density caused by out-diffusion. The SP equation and its analytical approximate solution provide a high degree of accuracy for the SP calculation, from which the closed-form I-V equations are derived. The proposed model uses physical parameters only and is implemented in Verilog-A code.
Keywords: compact model; p-GaN gate high-electron mobility transistors; physics-based models; surface potential.