A Characterization Method for Interfacial Delamination of Copper/Epoxy Mold Compound Specimens under Mixed Mode I/III Loading

The objective of this work is to develop a combined mode I and mode III characterization method and to use this test method to study Copper (Cu) / Epoxy mold compound (EMC) interfacial delamination from near-mode I to nearmode III global loading. Using the developed test method, a series of experiments are done with varying loading mode conditions from near-mode I to near-mode III and successful delamination of the Cu/EMC interface is observed in many cases. Three-dimensional finite-element analysis is carried out to get compliance vs crack length relationship for different loading conditions and is used to determine the crack length indirectly. The experiments indicate that as the mode mixity increases from mode I towards mode III, the critical load increases for a given crack length, and thus, the interfacial fracture energy increases with the increasing mode mixity.