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

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 f T and the transconductance G m are about 100 GHz (I d=2 A/mm) and 2 S/mm (V g=0.5 V), respectively. The high f T and G m values and high I d value when f T is at the maximum strongly suggest that the AlN/GaN hetero-MIS-FET has high potential as a high-frequency, high-power device.