ANALYSIS OF BENDING DISPLACEMENT OF LEAD-ZIRCONATE-TITANATE THIN-FILMSYNTHESIZED BY HYDROTHERMAL METHOD

Lead zirconate titanate solid-solution (PZT) films with various thickn esses were synthesized on titanium substrates by repeated hydrothermal treatments. Young's modulus and the density of the PZT film were meas ured by the vibrating-reed technique and Archimedes' method, respectiv ely, and they were lower than those of PZT ceramic. We fabricated bimo rph-type bending actuators using those films and analyzed the displace ment induced by the electric field. It was found that the piezoelectri c constant and electromechanical coupling factor of the PZT film were comparable to those of the ceramic, and also that the displacement was caused by the piezoelectric effect. The actuators were bent by applie d voltage without poling, because the polar axes in the as-deposited f ilm were aligned in the direction from the film surface to the substra te.