The goal of a measurement technique is to create a stress in the adhesive bond and then measure the response of the film to this stress. Regions of the film having weak bonding forces will produce a different response than the regions having strong bonding forces. Surface acoustic waves (SAW) are used to introduce the stresses and the change in the velocity of the waves is measured. The waves are excited on the substrate with a high numerical aperture cylindrical lens. The V(Z) response of the film system is then obtained and processed to extract the SAW velocity. The results of these measurements on a film system with known regions of strong and weak adhesion are presented. These measurements are compared to simulations of the change in surface wave velocity as the bond stiffness between the film and substrate is changed.
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