Using TCAD Simulation, we present a systematic analysis and comparison of a new vertical GaN split gate trench MOSFET (SGT-MOSFET) with a conventional trench gate MOS-FET for 600 V switching applications. We have calibrated our simulation models to match the experimental data as available in the literature. We show that the SGT-MOSFET exhibits 7 times lower HF-FOM (Crss ×Ron) and 3 times lower HF-FOM (QGD × Ron) without increase in the specific on-resistance, when compared to that of conventional MOSFET. We, also have presented the main process steps required for the fabrication of the proposed device. These improvements are important for reducing the conduction and switching losses, and making high frequency power conversion more efficient. © 2020 IEEE.