Piezoelectric micro-flextensional actuator

This paper presents a novel micro flextensional actuator design consisting of bulk PZT bonded to a silicon microbeam. The fabrication process includes boron doping, EDP etching, dicing, and bonding to produce actuators with large displacements (8.7 μm) and gain factors (32) at 100V. The theoretical model predicts that a thin beam with properly designed initial imperfection maximizes the actuator displacement and gain factor. For large PZT displacement, small imperfection maximizes gain factor but may not gaurantee, the desired (up or down) displacement direction. For small PZT displacement, large initial imperfection improves performance and guarantees displacement in the (desired) direction of the initial imperfection. The theoretical model, based on the measured initial beam shape, predicts the experimentally measured direction and magnitude of beam displacement for two devices.