Seal Rings Toughness Characterization by Numerical and Experimental Approaches

We present a device that provides in-situ optical observations of interface delamination along a heterogeneous surface with various interface strengths, namely chips with "crack stops" in their perimeters. We adopt a four-point bending test in which a glass plate is used that allows for the optical tracking of the crack advances. Because the interface strength is heterogeneous, drops in the force-displacement curve are observed, corresponding to a non-uniform crack advance. This is confirmed with a 2D finite elements simulation of the four-point bending test; the heterogeneous interface being described with a cohesive model. Results show that the method is reproducible and is able to detect the crack front in a complex interconnect environment. The coupling between force-displacement curve and observations provide insight on the crack propagation sequence. Based on this, some assumptions have been drawn, even if further work investigation is necessary. However, this new experimental approach is seen as a promising method for future characterization of crack growth.