Reliability evaluation on deterioration of power device using coupled electrical-thermal-mechanical analysis

Abstract

This paper presents a fundamental method to evaluate thermal fatigue life of power module. Coupled electrical-thermal analysis was performed to obtain the distribution of temperature due to electric current. Then, thermo-mechanical analysis was carried out to calculate inelastic strain range generated in a solder joint. Crack path simulation technique was used to evaluate total fatigue life and rise in temperature. Fatigue crack initiates under Al bonding wire for the IGBT module. Crack propagation induces the change in thermal properties of power devices. Total fatigue life changes with configuration of model.