High performance multi-channel MOSFET on InGaAs for RF amplifiers

In this paper, we propose a multi-channel MOSFET (MC-MOSFET) on In0.53Ga0.47As for the first time by utilising trenches in the conventional planar MOSFET (CP-MOSFET) for RF amplifier applications. The proposed multi-channel MOSFET (MC-MOSFET) has two vertical-gates placed in trenches creating multiple channels in p-body for parallel conduction of drain current. High-k Al2O3 having thickness of 2 nm is used as gate dielectric in the proposed device. The TaN gate electrodes are placed in two different trenches in the p-type InGaAs layer where multiple n-channels are formed. Simultaneous conduction from multiple channels enhances the drain current (ID) and gives higher transconductance (gm) leading to improvement in overall frequency response. Two-dimensional (2D) numerical simulations of both MC-MOSFET and CP-MOSFET are performed by using ATLAS device simulator and their different performance parameters are compared. The proposed multi-channel structure provides 6.79 times higher ID, 5.57 times improvement in gm, 2.5 times increase in unity current gain (ft), 15.85% higher unilateral power gain (fmax) and suppress the short-channel effects (SCEs) as compared with the CP-MOSFET.