Micromechanical adhesion experiments and simulation on Cu-damascene processed test devices

A novel experimental setup for testing interface properties of single copper interconnect structures is presented. The method is based on in-situ SEM nanoindentation experiments, utilized to probe customized copper structures manufactured by the Dual Damascene process. In this way the testing structures resemble product-like length-scales and properties. For the investigation of interface properties, the experimental loaddisplacement data is reviewed. Focused ion beam (FIB) cross sections are performed to validate the delaminated interface. FEM-simulations, based on the measured load-displacement data are used to determine the stress state in the test structures and to derive values for the interface fracture strength of the investigated interface.