Analysis of concurrent failure mechanisms in IGBT structures during active power cycling tests

Die attach degradation and bond wire damage are common failure modes in power electronics components. Power cycling testing is an effective way to trigger them, and combined with effective measurement technologies also to track their development while the pulses are applied. In both cases the assessment can be done based on voltage measurements. In case of bond wire degradation the collector-emitter voltage of the devices will increase, however in case of degradation of the thermal path, a similar elevation in the same voltage parameter can be expected. In this article we will show examples of both degradation types and also a simple method to distinguish between the two if they develop in the same time.