Way of operation to improve performance for advanced split-gate resurf stepped oxide UMOSFET

In this study, a way of operating a double split-gate resurf stepped oxide (DSGRSO) UMOS has been proposed. The n-drift region is divided into two parts by the double split-gate: the upper one and the lower one, which enhances the resurf active effect and binges in an electric field peak in the middle of the n-drift region, and decreases the width of split-gate trench, resulting in an increase of figure of merit (FOM). The simulation results show that the DSGRSO UMOS has improved the saturated breakdown voltage by 25.7% and FOM by 108% as compared with SGRSO UMOS at the certain aspect ratio.