Impact of gate engineering in enhancement mode n++GaN/InAlN/AlN/GaN HEMTs

Abstract This paper illustrate the effect of gate material engineering on the performance of enhancement mode n ++ GaN/InAlN/AlN/GaN high electron mobility transistors (HEMTs). A comparative analysis of key device parameters is discussed for the Triple Material Gate (TMG), Dual Material Gate (DMG) and the Single Material Gate (SMG) structure HEMTs by considering the same device dimensions. The simulation results shows that an significant improvement is noticed in the key analysis parameters such as drain current (I d ), transconductance (g m ), cut off frequency (f T ), RF current gain, maximum cut off frequency (f max ) and RF power gain of the gate material engineered devices with respect to SMG normally off n ++ GaN/InAlN/AlN/GaN HEMTs. This improvement is due to the existence of the perceivable step in the surface potential along the channel which successfully screens the drain potential variation in the source side of the channel for the gate engineering devices. The analysis suggested that the proposed TMG and DMG engineered structure enhancement mode n ++ GaN/InAlN/AlN/GaN HEMTs can be considered as a potential device for future high speed, microwave and digital application.