Performance of AlN/GaN Heterostructure Metal Insulator Semiconductor Field Effect Transistor Based on Two-dimensional Monte Carlo Simulation

Abstract

We performed a two-dimensional Monte Carlo simulation of an AlN/GaN heterostructure metal insulator semiconductor field effect transistor (hetero-MIS-FET). The vertical structure of the FET is AlN(6 nm)/GaN, and the gate length, the gate-to-source length and the gate-to-drain length are 0.2 µm, 0.2 µm and 0.4 µm, respectively. We assume that GaN and AlN are wurtzite structures and are grown along the c-axis. We took account of the total electric polarization of AlN of 3×10-6 C cm-2 due to piezoelectric and spontaneous polarization. Three valley models for the conduction band of GaN and AlN are employed. The maximum value of the cutoff frequency fT and the transconductance Gm are about 100 GHz (Id=2 A/mm) and 2 S/mm (Vg=0.5 V), respectively. The high fT and Gm values and high Id value when fT is at the maximum strongly suggest that the AlN/GaN hetero-MIS-FET has high potential as a high-frequency, high-power device.