Characteristics of Triple Material Gate AlGaN/GaN High Electron Mobility Transistor

A two dimensional simulation study has been executed to explore the characteristics of a newly proposed AlGaN/GaN High Electron Mobility Transistor (HEMT) device with triple material gate (TMG) structure. Surface potential and electric field distribution along the device channel are comprehensively examined and compared with those of dual material gate (DMG) and single material gate (SMG) HEMT. TMG HEMT shows better suppression of drain induced barrier lowering (DIBL) and hot carrier effect (HCE) due to the formation of two steps screening effect in channel potential and less amount of electric field peak at the drain terminal. Effect of different device parameters e.g. individual channel length related to different gate material, total channel length and externally applied voltage on the surface potential and electric field are also explored and proper choice of the device parameters and bias voltages is optimized to improve device performance, achieve high speed and reduce short channel effects (SCE) effectively.