Bond Wire Failure Monitoring of SiC MOSFETs Based on the Body Diode Voltage

Bond wire failure is one of the most critical aging forms of silicon carbide (SiC) MOSFETs. Currently, the existing electrical parameter condition monitoring methods are generally coupled with junction temperature and gate-oxide degradation, making it challenging to accurately monitor bond wire failure. This article introduces a new monitoring method for bond wire failure in SiC MOSFETs based on the body diode voltage under the −10-V gate-source voltage and a specific monitoring current. This condition monitoring method relies on the temperature-independent intersection in the output characteristic of the third-quadrant (3rd-quad) of SiC MOSFETs, which can decouple the coupling effects of junction temperature and the gate-oxide degradation and accurately monitor the failure state of the bond wire. The effectiveness and feasibility of the proposed condition monitoring method are verified in the double-pulse experimental platform in this article.