Reliability Challenges for SiC Power Devices in Systems and the Impact on Reliability Testing

The reliability of SiC devices remains to be a field of hectic activity because it is one of the obstacles for the ubiquitous application of SiC devices. Without decades of field experience, reliability testing, especially accelerated testing, is the only way to obtain information on reliability during the projected lifespan of the devices. For silicon devices, such tests exist and they are canonized in internationally recognized test standards. For SiC devices, these standards have to be revised and/or supplemented with tests to capture SiC specific degradation mechanisms. On the one hand, this requires a detailed knowledge about the mechanisms but on the other hand, this also requires the mission profile of the devices. In fact, it is not the mission profile of the device that determines its reliability but the mission profile of the chip. This contribution reviews the standard silicon tests useful for SiC devices and looks into additional, SiC specific tests that have been proposed but not yet been recognized as standards.