A new RF trench-gate multi-channel laterally-diffused MOSFET on InGaAs

Abstract

In this work, a new RF power trench-gate multi-channel laterally-diffused MOSFET (TGMC-LDMOS) on InGaAs is proposed. The gate-electrodes of the new structure are placed vertically in the trenches built in the drift layer. Each gate results in the formation of two channels in the p-body region of the device. The drain metal is also placed in a trench to take contact from the n+-InGaAs region located over the substrate. In a cell length of , the TGMC-LDMOS structure has seven channels, which conduct simultaneously to carry drain current in parallel. The formation of multi-channels in the proposed device increases the drive current ( leading to a large reduction in the specific on-resistance ( . Due to better control of gates on the drain current, the new structure exhibits substantially higher transconductance ( resulting in significant improvement in cut-off frequency ( and oscillation frequency ( . Using two-dimensional numerical simulations, a 55 V TGMC-LDMOS is demonstrated to achieve 7 times higher , 6.2 times lower , 6.3 times higher peak , 2.6 times higher , and 2.5 times increase in in comparison to a conventional device for the identical cell length.