Thermomechanical reliability of high density wiring substrates

The thermomechanical response of multi-layered high density wiring (HDW) substrates is influenced by various material and geometrical parameters. This study aims at understanding the role and interaction of various dielectric and base substrate materials on different failure mechanisms. Experimental thermals cycling results are presented and the failure modes observed in test samples are discussed. Nonlinear finite element models are developed to estimate the warpage of the substrate, stresses in the dielectric layer and solder bump strains. The input factors for the analysis are grouped under material properties and geometry, and a selection technique is used to identify important factors. Based on the study, a response surface is generated to understand the role and interaction of input parameters on various failure mechanisms, and such a response surface will be used to tailor material properties for the High Density Wiring (HDW) structures.