一种4H-SiC 1.7 kV额定嵌入式TMBS UMOSFET

A novel Trench MOS Barrier Schottky (TMBS) diode embedded UMOSFET in 4H-SiC is proposed and demonstrated in this work. MOSFETs with TMBS/UMOS ratio of 0, 1/3, and 1/2 are fabricated and evaluated. A UMOSFET where the trench depth is 1.5~ m and the mesa width is 1.6~ m shows a R _ on, {sp} of 5.8 m cm2 and a BV of 2040 V. Devices with TMBS cells embedded show no breakdown voltage degradation, and slightly increased R _ on, {sp} of 6.9 and 7.3 m cm2 for devices with TMBS/UMOS ratios of 1/3 and 1/2 respectively. The third quadrant reverse conduction voltage VSD is reduced from 6.3 V to 4.2 V and 3.5 V at a JD of 200 A/cm2 for devices with TMBS/UMOS =1/3 and 1/2, respectively. DC characteristics at elevated temperatures are measured, from which the temperature dependence of R _ on, {sp} and VTH in the first quadrant and VSD in the third quadrant can be extracted. Finally, the maximum unipolar operating voltage and current are extracted to provide guidelines for operation without bipolar degradation.