Thin film piezoelectric element, method of manufacturing the same, and actuator

DETAILED DESCRIPTION The present invention aims to improve the reproducibility of the shape of piezoelectric elements in etching, to prevent failures, e.
g.
short circuits between the electrodes sandwiching a piezoelectric thin film, and to provide a thin film piezoelectric element having excellent piezoelectric characteristics and few variations.
The present invention also aims to provide a method of manufacturing the piezoelectric element, and an actuator using the piezoelectric element.
According to one aspect of the present invention, there is provided a thin film piezoelectric element.
The thin film piezoelectric element includes a structure in which a first piezoelectric thin film, which is sandwiched (disposed) between a first main electrode layer and a first opposite electrode layer, and a second piezoelectric thin film, which is sandwiched between a second main electrode layer and a second opposite electrode layer, are coupled so that the first opposite electrode layer and the second opposite electrode layer are opposed to each other and are physically and electrically connected to each other.
The thin film piezoelectric elements also includes an insulating layer covering the outer periphery along the thickness of the structure.
The first main electrode layer in an electrode leading area has a first main electrode layer projection that partially extends from the first piezoelectric thin film.
A first connection wiring for connecting the first main electrode layer projection and the second main electrode layer is disposed via a first opening that is formed through the insulating layer on the first main electrode layer projection.
The second main electrode layer, the second piezoelectric thin film, and the second opposite electrode layer in the electrode leading area are formed narrower than the first opposite electrode layer so as to provide a region in which the insulating layer is provided on the first opposite electrode layer.
A second connection wiring for establishing an electrical connection to the first opposite electrode layer is provided via a second opening that is formed through the insulating layer in this region