RESURF Principle in AlGaN/GaN HEMTs: Accurate 1-D Modeling on Off-State Avalanche Breakdown Behavior via Effective Concentration Profile

Abstract

We present a simple but accurate 1-D methodology of modeling for AlGaN/GaN High Electron Mobility Transistors (HEMTs), and by which means study its Reduced Surface Field (RESURF) effect. By using the Effective Concentration Profile Concept, the proposed methodology accounts the interactions between each layer and electric field crowding induced by gate/drain electrodes simultaneously without introducing any simulation results and correction factors. The proposed model indicates that same as that in silicon-based lateral power devices, the RESURF effect is also present in AlGaN/GaN HEMTs. Thus, the channel layer doping of AlGaN/GaN HEMTs plays a leading role in determining the devices' off-state characteristics. Owing to the veracity and simplicity of the proposed model, in this paper, the devices' breakdown voltage and RESURF criterion are analytically obtained via a 1-D approach for the first time. The good agreements between the analytical model, experimental results, and 2-D simulations verify the validity of the proposed methodology.