DIELECTRIC THIN FILM ELEMENT, PIEZOELECTRIC ACTUATOR AND LIQUID DISCHARGE HEAD, AND METHOD FOR MANUFACTURING THE SAME

摘要

In piezoelectric thin films constituting crystalline dielectric thin film elements used for a piezoelectric actuator of a liquid discharge head, stress is generated in the crystallization step by heating due to the lattice misfit. Given this fact, by interposing between a substrate and intermediate layer which has a twin structure that absorbs the stress, film peeling and deterioration of the piezoelectric properties of the piezoelectric thin films are prevented. The intermediate layer is of a multi-layer structure which has a first intermediate layer comprising a twin structure thin film and a second intermediate layer which is the lower electrode, and because the substrate also serves as a lower electrode, the intermediate layer has a single layer structure comprising a twin structure thin film.