Silicon carbide power devices for high temperature, high power density switching applications

Silicon carbide (SiC) can produce high performance power devices capable of operating at high temperature. Its avalanche breakdown field and bandgap are higher than silicon and its thermal conductivity is higher than copper at room temperature. Packaging and cooling requirements, and thermal expansion coefficient mismatches of the SiC and the device packaging may be the ultimate limitations to the high current density operation of SiC thyristors, but operation at 10 kA/cm² is feasible with cooling and packaging improvements. By taking advantage of the thermal properties of lower voltage SiC devices with thin blocking layers and operating at 8 kA/cm², a 60% reduction in device size and weight can be realized at the expense of a 17% increase in losses.