Effects of Variation in Gate Material on Enhancement Mode P-GaN AlGaN/GaN HEMTs

Abstract

A Enhancement type/Normally-OFF AlGaN/GaN High Electron Mobility Transistor (HEMT) is used in power devices because gallium nitride (GaN) has advantages over silicon. GaN-based HEMTs have proven to be excellent devices for applications requiring high frequency, high strength, and high temperature. Without any gate bias, a AlGaN/GaN HEMT device will work in depletion mode because of 2D electron gas formation at the interface of GaN and AlGaN. In this chapter, we have studied the effects of variation in gate material on the performance of enhancement mode a P-GaN-based AlGaN/GaN HEMT. P-GaN HEMT creates a depletion region at the channel or at the interface of AlGaN and GaN. Due to the formation of the depletion region, the proposed device will work in normally-off mode. In this proposed work, different gate materials have been used to achieve optimized drain current, trans-conductance and cut-off frequency. The gate materials vary from 3.9eV to 5.93eV with a gate length of 1μm.