Theoretical analytic model for RESURF AlGaN/GaN HEMTs**Project supported by the National Basic Research Program of China (Grant No. 2015CB351906), the National Natural Science Foundation of China (Grant No. 61774114), the Key Program of the National Natural Science Foundation of China (Grant No. 61334002), and the 111 Project, China (Grant No. B12026).

Abstract

In this paper, we propose a two-dimensional (2D) analytic model for the channel potential and electric field distribution of the RESURF AlGaN/GaN high electron mobility transistors (HEMTs). The model is constructed by two-dimensional Poissonʼs equation with appropriate boundary conditions. In the RESURF AlGaN/GaN HEMTs, we utilize the RESURF effect generated by doped negative charge in the AlGaN layer and introduce new electric field peaks in the device channels, thus, homogenizing the distribution of electric field in channel and improving the breakdown voltage of the device. In order to reveal the influence of doped negative charge on the electric field distribution, we demonstrate in detail the influences of the charge doping density and doping position on the potential and electric field distribution of the RESURF AlGaN/GaN HEMTs with double low density drain (LDD). The validity of the model is verified by comparing the results obtained from the analytical model with the simulation results from the ISE software. This analysis method gives a physical insight into the mechanism of the AlGaN/GaN HEMTs and provides reference to modeling other AlGaN/GaN HEMTs device.