An electromechanical transducer includes a first electrode; a silicon oxide film disposed on the first electrode; and a vibration film including a silicon nitride film disposed on the silicon oxide film with a space therebetween and a second electrode disposed on the silicon nitride film so as to oppose the first electrode.

Layer structures for RF filters can be fabricated using rare earth oxides and epitaxial aluminum nitride, and methods for growing the layer structures. A layer structure can include an epitaxial crystalline rare earth oxide (REO) layer over a substrate, a first epitaxial electrode layer over the crystalline REO layer, and an epitaxial piezoelectric layer over the first epitaxial electrode layer. The layer structure can further include a second electrode layer over the epitaxial piezoelectric layer. The first electrode layer can include an epitaxial metal. The epitaxial metal can be single-crystal. The first electrode layer can include one or more of a rare earth pnictide, and a rare earth silicide (RESi).

A piezoelectric element includes a first electrode; a piezoelectric layer, placed on or above the first electrode, containing potassium, sodium, niobium, titanium, and oxygen; and a second electrode placed on or above the piezoelectric layer.

A manufacturing method of an epitaxial thin film piezoelectric element includes: providing a substrate; forming a bottom electrode layer on the substrate by epitaxial growth process; forming a first piezoelectric layer that has c-axis orientation on the bottom electrode layer by epitaxial growth process; forming a second piezoelectric layer that has c-axis orientation and different phase structure from the first piezoelectric layer on the first piezoelectric layer by epitaxial growth process; and forming a top electrode layer on the second piezoelectric layer. The thin film piezoelectric element has good thermal stability, low temperature coefficient and high piezoelectric constant.

A piezoelectric device used in a liquid ejecting head that ejects liquid from a nozzle includes a flow path forming substrate in which an individual liquid chamber that communicates with the nozzle, and a liquid supply chamber that communicates with the individual liquid chamber are formed, a vibration plate formed at a position corresponding to the individual liquid chamber and the liquid supply chamber of the flow path forming substrate, a plurality of liquid supply ports formed in the liquid supply chamber, and a piezoelectric element including a first electrode, a piezoelectric layer, and a second electrode, the piezoelectric element being formed at a position on the vibration plate corresponding to the individual liquid chamber. A metal layer is stacked at a position on the vibration plate corresponding to the liquid supply chamber. The liquid supply ports are provided so as to penetrate the vibration plate and the metal layer.

A film structure body has: a substrate that is a silicon substrate including an upper surface composed of a plane; an orientation film including a zirconium oxide film that is cubic crystal-oriented on the upper surface; and a conductive film including a platinum film that is cubic crystal-oriented on the orientation film.

Provided is a piezoelectric element including: a first electrode; a piezoelectric layer which is provided over the first electrode; and a second electrode provided on a side of the piezoelectric layer opposite to the first electrode, in which the second electrode includes a first layer which is provided on the piezoelectric layer side, and a second layer which is provided on a side of the first layer opposite to the piezoelectric layer, and the second layer does not contain platinum and covers an end portion of the first layer.

A method of fabricating a monocrystalline piezoelectric layer, wherein the method comprises: supplying a donor substrate of the piezoelectric material, supplying a receiving substrate, transferring a layer called a seed layer from the donor substrate onto the receiving substrate, and implementing an epitaxy of the piezoelectric material on the seed layer until a required thickness for the monocrystalline piezoelectric layer is obtained.

Provided is a liquid ejecting head that ejects a liquid in a pressure chamber by a piezoelectric device, the piezoelectric device including a vibration plate, a piezoelectric layer containing lead, a first electrode provided between the vibration plate and the piezoelectric layer, and a second electrode provided on a side opposite to a side of the first electrode as viewed from the piezoelectric layer. The piezoelectric layer is preferentially oriented in a (100) plane, a lattice constant c defined by a crystal plane of the piezoelectric layer parallel to a film surface of the piezoelectric layer and a lattice constant a defined by a crystal plane perpendicular to the film surface satisfy 0.9945?c/a?1.012, and the thickness of the piezoelectric device is twice or more the thickness t (t<5 ?m) of the piezoelectric layer.

An electromechanical transducer element including a lower electrode, an electromechanical transducer film and an upper electrode formed on the electromechanical transducer film.