Current Sensing for SiC Power Devices

Abstract

High voltage, high current capabilities of SiC based devices has been already proved, and high current SiC devices working at high temperature are likely to be on the market soon. SiC power integration will have to be considered as a further development step to discrete power devices. Packaging and device integrated protections remain the main constraints for high temperature operation and system integration. In case of short-circuit or over-current, SiC devices can reach high temperature values, and the die might be subjected to high stresses. In order to address such critical requirements, current sensing and real time temperature monitoring are mandatory. The structure proposed in this paper, derived from Si technology, provides a protection feature to SiC power devices to get reliable high temperature electronics. Concretely, an integrated current sensor has been implemented in a vertical power SiC JFET and its fabrication is reported for the first time. The current sensor layout and process technology are presented. An experimental current sensing validation is also reported.