Failure analysis in power devices using lock-in infrared thermography

摘要

In this work, the Infrared Lock-in Thermography (IR-LIT) is reported as a powerful tool for power devices diagnosis. They are monitored by thermal means after being biased in the frequency domain to activate and locate the weak spots responsible for their misbehaviour. As case studies, three different power devices are analysed: i) a Vertical Double Diffused MOS (VDMOS) presenting an elevated gate leakage current; ii) a SiC Schottky Barrier Diode with Tungsten contact (W-SBD) featuring a Schottky barrier modification by metal contact change; and iii) a Rad-Hard V-JFET with a lower breakdown voltage and a higher gate leakage current than expected.