Numerical evaluation of thermal cycling reliability of high performance flip-chip package assembly using submodeling analysis

This paper applies the submodeling technique in analyzing thermal cycling reliability of high performance flip-chip ball grid array package assemblies. The packages have one-piece tunnel-type heat spreaders with different lead widths, connected to chips using different thermal interface materials. The global model contains no solder bumps to simplify the analysis. The calculated displacement field of the global model is then interpolated on the boundary of the submodel that contains the critical solder bump. The submodel is solved using the prescribed displacement boundary conditions together with external thermal loads to evaluate thermomechanical reliability of the critical solder bump.