Development of a 250°C 15kV Supercascode switch using SiC JFET technology

Tetra Corporation is developing a pulsed power drilling system for the geothermal industry. The system requires a high temperature switching technology to replace the existing technology based on Si thyristors with a temperature limit of 150°C. This work focuses on the development of such switch based on a Supercascode configuration using SiC JFET technology. The development presented contains thermal models, packaging design and processes, circuit simulations and prototypes of both the Supercascode switch and the high temperature packaged SiC JFETs.