Reliability simulation with the finite element analysis (Fea) of redistribution layer in fan-out wafer level packaging

In order to improve the performance and reliability of the package, the interlayer dielectric (Polymer) must not be delaminated and materials should not fracture due to thermal stresses during the operation or the manufacturing process, and the insulation performance between the wiring layers must not be decreased. The critical energy release rate (Gc) of the photosensitive polymer film (2-types of polyimides, polybenzoxazole, and phenolic resin) on the copper were evaluated by the Peel Test. We created material-specific master curves (time–temperature superposition) by considering the measurement results of the Peel Test at the Cu/Polymer interface and the mechanical properties of polymer. In addition, we calculated the energy release rate (G) from finite element analysis (FEA) in FOWLP structure. As a result, the new innovative reliability simulation was made possible by normalizing Gc and G. This study has made it possible to simulate the delamination possibility of Cu/Polymer interface at arbitrary temperatures and displacement rates from basic material data and FEA analysis of the FOWLP structure.