Life prediction of bonding interface in power module under thermal cycling loading
                                         GUO Yuan qi1, GAO Tao2, XU Yang jian1, LIANG Li hua1, LIU Yong1
(1.College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310014, China；2.China United Engineering Corporation, Hangzhou 310052, China)

Abstract: Aiming at the fatigue failure problem of the wire bonding parts of power module under thermal cycling, the fatigue life of power module under thermal cycling loading was studied, thermal cycling tests were carried out by using the power modules with three different packaging materials with the help of thermal cycling test chamber. Combining with the sub model technique, the finite element simulation was conducted to determine the dangerous locations in the wire bonding parts and their life predictions was performed by using the Coffin Manson fatigue life prediction theory. At the same time, based on the cohesive zone model and damage evolution theory, using of ABAQUS user defined program interface UEL, a life prediction method was developed and the fatigue lives of the bonding interface were further predicted by using our own program. The results indicate that these two types of life prediction methods are both suitable for life prediction of wire bonding. The method of cyclic cohesive zone model can yield more matched results in comparison with the experiments and can reproduce the failure progress of wire bonding interfaces.

Key words: thermal cycling; wire bonding; life prediction; cyclic cohesive zone model