In this study, we developed a system allowing interfacial adhesion
measurements as a function of mode-mixity, from pure tension to pure shear.
Results show that the debonding energy increases, by a factor of 3 to 10, as
the amount of shear stress increases, approaching mode II conditions. For
low k dielectrics, the debonding energy was found to decrease with
increasing porosity and increase with increasing plasticity. The crack
propagation is also dependent on mode-mixity.