Materials Science Forum, Vol.483, 797-800, 2005
4H-SiC DMOSFETs for high speed switching applications
Due to the high critical field in 4H-SiC, the drain charge and switching loss densities in a SiC power device are approximately 10X higher than that of a silicon device. However, for the same voltage and resistance ratings, the device area is much smaller for the 4H-SiC device. Therefore, the total drain charge and switching losses are much lower for the 4H-SiC power device. A 2.3 kV, 13.5 M&UOmega;-cm(2) 4H-SiC power DMOSFET with a device area of 2.1 mm x 2.1 mm has been demonstrated. The device showed a stable avalanche at a drain bias of 2.3 W, and an on-current of 5 A with a V-GS of 20 V and a V-DS of 2.6 V. Approximately an order of magnitude lower parasitic capacitance values, as compared to those of commercially available silicon power MOSFETs, were measured for the 4H-SiC power DMOSFET. This suggests that the 4H-SiC DMOSFET can provide an order of magnitude improvement in switching performance in high speed switching applications.