Self-aligned 6H-SiC MOSFETs withimproved current drive

Surface-channel n-MOSEET devices in 6H-SiC are fabricated with n+-polysilicon gates on 80 nm thick gate oxide using a self-aligned process. The mobility and subthreshold slope, 40 cm2/Vs and 500 mV/decade, are comparable to MOSFETs fabricated with a non-self-aligned process. These MOSFETs exhibit a saturation drain current of 18 mA/mm at 340°C when the gate is 9 V above threshold. This current density is approximately three times higher than the best self-aligned 6H-SiC MOSFETs reported to date, and approximately five times higher if scaled to the same oxide thickness.