A 10-kV Monolithic Darlington Transistor With $\beta _{ \rm forced}$ of 336 in 4H-SiC

4H-SiC bipolar Darlington transistors with a record-high current gain have been demonstrated. The dc forced current gain was measured up to 336 at 200 W/cm² ( J _C = 35 A/cm² at V _CE = 5.7 V) at room temperature. The current gain exhibits a negative temperature coefficient and remains as high as 135 at 200degC. The specific on-resistance is 140 mOmegamiddotcm² at room temperature and increases at elevated temperatures. An open-emitter breakdown voltage (BV _CBO) of 10 kV was achieved at a leakage current density of < 1 mA/cm². The device exhibits an open-base breakdown voltage (BV _CEO) of 9.5 kV. The high current gain of SiC Darlington transistors can significantly reduce the gate-drive power consumption with the same forward-voltage drop as that of 10-kV SiC bipolar junction transistors, thus making the device attractive for high-power high-temperature applications.