Stress analysis for fracturing potential of blind via in a build-up substrate

Purpose ‐ The submodeling technique is incorporated in a finite element analysis to investigate the stress state of blind vias of different structural configurations. Design/methodology/approach ‐ The test vehicle is a multi-chip module plastic ball grid array comprised of a four-layer build-up substrate. The calculated displacement field from the global model for the entire package is interpolated on the boundaries of the submodel, which involved the detailed structure of a blind via structure. Through the analysis, the potential of fracturing on the blind via is examined. Findings ‐ From the analysis it was found that filled blind vias in general have a smaller potential for delamination compared to the unfilled ones. Moreover, symmetric blind via layouts with a blind via located at the center of the through hole appear to be the most appropriate design for this particular test vehicle. Originality/value ‐ The value of the paper lies in its ability to provide insights into the prevention of fracturing of blind vias in a build-up substrate through a novel numerical analysis using the submodeling technique.