Effects of Creep Failure Mechanisms on Thermomechanical Reliability of Solder Joints in Power Semiconductors

This article deals with the effects of creep failure mechanism on thermomechanical reliability of power semiconductors. Regarding power semiconductors' working conditions, fatigue and creep failure mechanisms are the two most critical failure origins in power semiconductors. Here, we propose an approach to show the role of creep event on the creep-fatigue failure mechanism of a power semiconductor. The results show that 34% difference in the lifetime prediction appears when the creep is considered in the estimations. This indicates that the extra effect of creep on fatigue evolution of power systems can markedly decrease the lifetime, which is ignored in many cases. Moreover, a logarithmic trend for thermal resistance and on-state voltage drop upon increase in number of thermomechanical cycles implies the accelerated aging of power semiconductor.