Bonding wire fatigue life prediction of power module in thermal cycling test

In this paper, 3-D finite element (FE) models were established to investigate the fatigue lives of bonding wire in different power packages in thermal cycling test. Meanwhile, three types of packages were tested. Bonding wire lift-off and neck failures took place during test, which were caused by the coefficient of thermal expansion (CTE) mismatch between wire and chip. Finally, a strain-based life prediction relation for thermal cycling test was proposed by combining the experiment results with simulation data.