Experimental Comparison of a New 1.2 kV 4H-SiC Split-Gate MOSFET with Conventional SiC MOSFETs in Terms of Reliability Robustness

Abstract

In this paper, we compare a new 1.2 kV rated 4H-SiC split-gate (SG) MOSFET with the conventional planar-gate (PG) MOSFETs. Both structures were fabricated with the same design rules and process platform. Therefore, the structures have similar electrical parameters, such as ON-state drain-source resistance (RON), breakdown voltage (BV), threshold voltage (Vth), and body diode forward voltage (VSD). It is shown that the Ciss/Coss/Crss capacitances of the SG-MOSFET can be reduced by 7%/8%/17%, respectively, compared with PG-MOSFET. It is also shown that the SG-MOSFET has the potential to reduce switching losses without compromising the static performance. Moreover, it maintains the robustness of the device, and an optimized layout design with spaced holes in the gate poly is adopted. Therefore, there is no obvious degradation between the SG-MOSFET and the PG-MOSFET in terms of avalanche and short-circuit endurance capabilities.