Solder Crack Simulation using SPH Particle Method with Sub-modeling Technique

In order to improve the mechanical reliability of IC packages crack generation and its propagation which are caused by such as Chip Package Interaction (CPI) are being investigated by various simulation methods. In this study, Smoothed-particle hydrodynamics (SPH) were first applied to analyze the crack propagation in a solder ball in a Flip Chip Ball Grid Array (FCBGA). SPH simulation is a meshless Lagrangian technique which is appealing as a possible alternative to techniques currently used to analyze complicated structures, fracture of materials and high deformation events. In this study, the SPH algorithm has been developed to elasto-plastic analysis and fracture analysis in the field of semiconductor structural dynamics. Then, heat conduction analysis and structural analysis using SPH theory were performed to analyze thermal stresses in FCBGA. Also sub-modeling approach was used to simulate crack propagation in solder balls which links the deformation from the package level to the solder ball level. The results show the crack initiation and crack propagation in solder balls clearly. SPH method is suite for computing fracture of solid materials because of the meshless algorithm and successfully applicable to crack propagation problems of semiconductors.