Design Optimization of High Breakdown Voltage AlGaN/GaN High Electron Mobility Transistor with Insulator Dielectric Passivation Layer

Abstract

AlGaN/GaN high electron mobility transistors (HEMTs) possess favorable material properties and are compatible with largescale manufacturing, making them promising as a next-generation power device. However, there is a lack of information available on the effect of an insulator dielectric passivation layer on the breakdown voltage (V br ) of AlGaN/GaN HEMTs. This study utilizes technology computer aided design to investigate the impact of different insulator dielectric passivation layers, such as SiO 2 , SiN, Al 2 O 3 , and HfO 2 , on V br of AlGaN/GaN HEMTs. Furthermore, the study optimizes the parameters of the field plate length (L FP ) and insulator thickness to maximize V br of AlGaN/ GaN HEMTs. Results indicate that HEMTs with a field plate (FP-HEMTs) have greater V br than HEMTs without a field plate (N-HEMTs). With the optimized conditions of a 1.8 µm L FP and a 0.95 µm insulator thickness with HfO 2 passivation, V br of 1120 V is achieved. The findings suggest that the field plate (FP) and passivation layer can significantly improve the efficiency and reliability of AlGaN/GaN HEMTs while the impact of AlGaN/GaN heterostructure parameters on V br is minimal.