Comparative Study of Solder Strength Characterization for BGA Packages

Ball Grid Array (BGA) packaging market is observing vibrant growth because of the increasing demand of electronic packaging in recent years. The dimension and functionality of the solder interconnection has been moving toward smaller form factor. In the study, four types of mechanical characterization method (Ball shear, cold bump pull, hot bump pull, and epoxy-encapsulated bump pull) will be applied on three kinds of lead-free solder (SAC305, SAC302, and LF35). The force value and failure mode will be compared in the study. In force value perspective, hot bump pull test method has higher standard deviation value than other methods. In terms of failure mode, pad peeling is likely to occur in hot bum pull. Intermetallic compound layer crack and mixed failure mode are two majority of failure modes in all three lead-free solders.