Adhesion strength of the interface between Cu film and SiCN cap layer for IC metallization system was evaluated by a technique developed by the authors. In this technique, microscopic specimens with the in-plane dimension less than 10 μm were fabricated by focused ion beam system and loaded directly by a sharp diamond stylus with submicron tip radius. By comparing the crack extension behavior with the three-dimensional numerical simulation, the interface adhesion energy was evaluated to be 5 J/m2. The same interface was subjected also to the four-point bending experiment, which is widely applied to interface adhesion measurement. The evaluation results by the two techniques agreed reasonably well with each other.