Piezoelectric device

Abstract

A piezoelectric device comprising a substrate having a cavity, a piezoelectric film covering the cavity and being supported by the substrate, and electrodes disposed so as to sandwich the piezoelectric film. The piezoelectric film has a convex-shaped or concave-shaped vibrating region disposed on the cavity. The vibrating region is configured by a single-layer piezoelectric film including a first region composed of a first piezoelectric material and a second region composed of a second piezoelectric material having a piezoelectric constant larger than that of the first piezoelectric material. A first electrode and a second electrode are disposed so as to sandwich the second region of the piezoelectric film, a first input signal is converted to a first output signal based on displacement at the second region of the piezoelectric film between these electrodes, and a piezoelectric device comprising a convex-shaped vibrating region with high power and high sensitivity is provided.

Dependencies are inferred from the claim text.