Effects of Packaging Materials on the Reliability of System in Package

System in package (SiP) has the ability to integrate other components, such as passive component and antenna, into a single package to realize complete system functions. However, there are many electrical and mechanical reliability issues including the reliability issue for embedded structures. A mismatch of thermal coefficients of expansion among packaging materials and devices can lead to warping or delamination in the package. In tins study, the effect of material properties of underfill and EMC, such as Young's modulus and CTE are investigated through FEM simulation. In the FEM analysis, the warpage of the package, the maximum principle stress in the die and the maximum shear stress on the interface between the substrate, undefill and EMC's surface are considered. Experimental investigation on the warpage measurement of the package is carried out to verify the simulation results. In addition, some geometry parameters, such as the underfill"s profile and EMC thickness, are also considered as the influencing parameters for the reliability of the package. Process optimization study. i.e.. replacing underfill with EMC is also carried out to improve the manufacturing process. The results show that the reliability of the system in package is closely related to the material properties and the geometry structures of underfill and EMC. The replacement of underfill with EMC improves the reliability performance of the package significantly. Results of this study provide a good guidance for the structure/process design and material selection when developing a SiP module.