High power 4H-SiC thyristors

For very high voltage, high current devices (>3 kV, >100 A), the use of bipolar SiC devices will be required because of their much higher current densities. These devices have applications in the area of traction control and power transmission. In this report, higher voltage and higher current npnp 4H-SiC thyristors have been achieved. The npnp device is the most promising thyristor structure to date because it allows the use of a low resistivity n-type substrate. A mesa structure was utilized, with all of the doping being done in situ during epitaxy. The device periphery was terminated using a reactive ion etched mesa, and the gate was contacted by performing a trench etch, again with reactive ion etching.