980 V, 33A Normally-Off 4H-SiC Buried Gate Static Induction Transistors

Abstract

In this work, we succeeded in developing high performance normally-off SiC buried gate static induction transistors (SiC-BGSITs). To achieve the normally-off characteristics, design parameters around the channel region were optimized and process conditions were improved to realize these parameters. The off-state characteristic of the SiC-BGSIT showed an avalanche breakdown voltage of VBR=980 V at a gate voltage of VG=0 V. Furthermore, the leakage current at VD=950 V is lower than 0.5 μA. These results indicate that the BGSIT has a good normally-off characteristic. At VG=2.5 V, an on-resistance of 28.0 mΩ corresponding to the specific on-resistance of 1.89 mΩ•cm2 was obtained and the current rating was calculated as 33 A at a power density of 200 W/cm2 in the on-state characteristic.