Application of submodeling technique to transient drop impact analysis of board-level stacked die packages

The objective of this research is to investigate the effects of board-level drop test based on the support excitation scheme incorporated with the submodel technique for stacked-die packages. This paper also demonstrates the transient dynamic response for lead-free SAC405 (95.5Sn4Ag0.5Cu) solder balls subject to JEDEC pulse-controlled board-level drop test standard JESD22-B110A Condition B. To evaluate the structure of the interested area, a strip model sliced from the full test vehicle is used in this research. In addition, the submodel region is particularly chosen with strip model by performing the cut boundary interpolation. The envelope of equivalent stress for the outermost solder joint off the end of the strip model is plot to show the potential solder failure mode and mechanism. The cut boundary of submodel is verified and the mesh density of submodel is examined. For a refinery mesh of submodel, parametric studies are carried out to study the reliability of the outermost solder joint, and the results are summarized as design rules for the development of stacked-die packages.