ABSTRACTA new radio frequency (RF) laterally diffused semiconductor field-effect transistor (MOSFET) (LDMOS) structure called multi-channel trench-gate (MCTG-LDMOS) is proposed on silicon-on-insulator. The MCTG-LDMOS structure consists of identical trenches in the drift region in which gate-electrodes are placed vertically. An n+-Si layer over buried-oxide serves as drain region which is connected to drain metal placed in a trench. Each gate-electrode creates two channels vertically in p-base on either side of its trench. In this study, four gate-trenches are built in a cell pitch of 5 µm resulting in formation of eight channels which carry current in parallel from drain to source electrodes. Based on two-dimesional simulations results, a 50 V MCTG-LDMOS is demonstrated to achieve 6.1 times higher drive current, 2.2 times reduction in specific on-resistance, 6.9 times improvement in transconductance, 2.1 times increase in cut-off frequency, and 3.2 times higher maximum oscillation frequency when compared with a 50 V conventional LDMOS for same cell pitch.