A physical Charge-based Model for threshold voltage of p-GaN Gate HEMTs

This paper proposes a physics-based analytical model for threshold voltage of p-GaN gate HEMT. Based on the EPFL HEMT model, the electric potential obtained by the Poisson's equations is combined with the discontinuity of the interface displacement vector to get the analytical threshold voltage model, considering the total negative polarization induced charge density at the p-GaN/AlGaN interface and the Mg out-diffusion of the p-GaN gate layer. Additionally, the resulting threshold voltage transients are explained using technology computer-aided design (TCAD) simulations, and good results verify the correctness of our derivation.