Thermo-Mechanical Modeling of Plastic-Core Solder Balls in LTCC/BGA Assemblies

In this paper, a reliability modeling methodology for BGA solder joints with plastic-core solder balls (PCSBs) has been presented. The methodology is applied to predict the board-level reliability of LTCC/BGA modules under accelerated thermal cycling conditions. The model takes into account both time- and temperature-dependent as well as time-independent plasticity and provides a detailed number of cycles needed to crack initiation, propagation and eventual solder joint failure. To assess the feasibility of the presented modeling procedure, the model is validated against experimental temperature cycling data obtained from LTCC/BGA module assemblies on a printed wiring board. The results demonstrate that this procedure can be used for life-time prediction of BGA solder joints with PCSBs