Switching and Short-Circuit Performance of 27 nm Gate Oxide, 650 V SiC Planar-Gate MOSFETs with 10 to 15 V Gate Drive Voltage

In this paper, the switching and short-circuit performance of 650 V (BV=850V) 4H-SiC planar-gate MOSFETs with a gate oxide thickness of 27 nm are reported for the first time. The switching and short-circuit withstand times (t
SC
) of devices with gate oxide thickness of 55 nm and 27 nm have been compared at various gate voltages. The R
on,sp
for the 27 nm device at V
gs
= 15 V is 1.7x smaller than that for the conventional 55 nm device at V
gs
=20 V while their total switching energy loss (E
total
) is the same. The t
SC
for the 27 nm device at V
gs
= 10 V is 1.5x better than the 55 nm device at V
gs
=20 V. It is demonstrated for the first time that a much better trade-off can be obtained between shortcircuit capability and the specific on-resistance (R
on,sp
) by reducing the gate oxide thickness from 55 to 27 nm.