[IEEE 2018 Iranian Conference on Electrical Engineering (ICEE) - Mashhad (2018.5.8-2018.5.10)] Electrical Engineering (ICEE), Iranian Conference on - Investigating a Novel Normally-On AlGaN/GaN Capped PHEMT and the Effects of Cap Layers Thickness on its Gate Leakage Current

摘要： In this paper the effects of cap layers thickness in the AlGaN/GaN capped pseudomorphic high electron mobility transistor (PHEMT) are investigated using Atlas/Silvaco Simulator. The proposed structure improves the prior AlGaN/GaN capped HEMT reported in the literature by insertion of an In0.15Ga0.85N layer between the AlN spacer and the GaN buffer layers and optimization of the different layers dimensions, in order to minimize gate leakage current. Simulation results demonstrate a gate leakage current of 10-14 (A) and an Ion/Ioff of higher than 11 orders of magnitude, so that it is 3 orders of magnitude higher than that of the prior non-optimal structure.