Thermal stress analysis and optimization for a power controller SiP module

In this paper, the finite element analysis method is used to investigate the thermal-mechanical behaviors of a power controller SiP module under power load. The effects of die attach (DA) material and epoxy molding compound (EMC) on the maximum temperature and maximum stress in the die are investigated. The packaging materials and geometry parameters of the module are optimized according to the simulation results. The results illustrate that the maximum temperature of die decreases with increase in EMC thickness or DA material thickness. The maximum stress is located at the corner of die, and the thickness of DA material and the CTE of EMC have different influence on the thermal-mechanical stress induced in the die. After optimizing, the maximum temperature could decrease about 3.437 K, and the maximum equivalent stress and shear stress could decrease by 25.7% and 33.4%, respectively.