Static and dynamic mechanical properties measurement of micro-nano metal thin film using cantilever beam deflection

A technique for studying the mechanical behavior of thin metal films is presented. The test specimen was designed to deposit on a novel triangle shape “paddle” beam in order to provide uniform plane strain distribution. Standard clean room processing was used to prepare the sample. The experiments were operated by using the electrostatic deflection on the “paddle” cantilever beam and measure the thin films on top by laser reflected into the position sensor. The measured strain was converted through a simple geometry calculation for the deflection of the cantilever. The static testing results on the Young's modulus of different thickness Al films were obtained in this research. The dynamic properties of thin film were also studied using the dynamic frequency response of the paddle structure generated by electrostatic force under different vacuum pressure. The results indicated the vacuum pressure affect the paddle sample free damping time. In addition, loss mechanism of dynamic response gives potential evidences of grain boundary motion or dislocation motion in the film.