A method of manufacturing a piezoelectric element includes: forming a patterned mask layer over a substrate, in which the patterned mask layer has an opening exposing a portion of the substrate; forming a piezoelectric element in the opening; and removing the patterned mask layer to obtain the piezoelectric element, in which the piezoelectric element has a central portion and a peripheral portion adjacent to the central portion, and the peripheral portion has a maximum height greater than a height of the central portion.

A hybrid structure for a surface acoustic wave device comprises a useful layer of piezoelectric material having a first free surface and a second surface disposed on a support substrate that has a lower coefficient of thermal expansion than that of the useful layer, wherein the useful layer comprises an area of nanocavities.

A method for manufacturing a substrate for a radiofrequency filter by joining a piezoelectric layer to a carrier substrate via an electrically insulating layer, wherein the method comprises depositing the electrically insulating layer by spin coating an oxide belonging to the family of SOGs (spin-on glasses) on the surface of the piezoelectric layer to be joined to the carrier substrate, followed by an anneal for densifying the electrically insulating layer before joining the piezoelectric layer to the carrier substrate via the electrically insulating layer.

A piezoelectric element in which a first electrode, a piezoelectric layer, and a second electrode are stacked on a substrate is provided. The piezoelectric element is a piezoelectric element in which the first electrode, the piezoelectric layer, and the second electrode are stacked in order on the substrate and includes an orientation control layer that is provided between the piezoelectric layer and the first electrode and that controls orientation of the piezoelectric layer and a titanium layer that is provided between the first electrode and the orientation control layer and that contains at least Ti.

There is provided a piezoelectric film, being a polycrystalline film comprised of potassium sodium niobate; containing at least one metal element selected from a group consisting of Cu and Mn; and having 1.0 or less ratio of a concentration B of the metal element at grain boundaries of crystals, with respect to a concentration A of the metal element in a matrix phase of the crystals.

A piezoelectric sensor and a manufacturing method thereof, a method for recognizing a fingerprint, and an electronic device are disclosed. The piezoelectric sensor includes a first electrode layer and a second electrode layer which are opposite to each other and a piezoelectric layer. The piezoelectric layer is between the first electrode layer and the second electrode layer and includes a plurality of piezoelectric units arranged at intervals and an insulation layer between adjacent piezoelectric units of the plurality of piezoelectric units. The first electrode layer includes a plurality of sub-electrodes corresponding to the plurality of piezoelectric units, or the second electrode layer includes a plurality of sub-electrodes corresponding to the plurality of piezoelectric units; or both the first electrode layer and the second electrode layer include a plurality of sub-electrodes corresponding to the plurality of piezoelectric units.

A vibration device includes a tubular body with a cavity, a first opening end surface, and a second opening end surface, a piezoelectric device joined to the first opening end surface, and a translucent cover joined to the second opening end surface. The tubular body and the piezoelectric device are joined to each other with a first adhesive layer, and the tubular body and the translucent cover are joined to each other with a second adhesive layer.

The present disclosure relates to a method of forming a device. The method includes depositing a first layer of getter material on a substrate. A first electrode is formed in a first conductive layer deposited on the first layer of getter material. An insulator element is formed in a piezoelectric layer deposited on the first electrode. A second electrode is formed in a second conductive layer deposited on the insulator element. A first input-output electrode is formed to be conductively connected to the first layer of getter material and a second input-output electrode is formed to be conductively connected to the second electrode.

A piezoelectric thin-film element includes a first electrode layer, a piezoelectric thin film stacked on the first electrode layer, and a second electrode layer stacked on the piezoelectric thin film. A performance index P of the piezoelectric thin film is defined as (d.sub.33,f).sup.2?Y/?. d.sub.33,f is a piezoelectric strain constant of thickness longitudinal vibration of the piezoelectric thin film. Y is a Young's modulus of the piezoelectric thin film. ? is a permittivity of the piezoelectric thin film. The performance index P is from 10% to 80.1%.

Methods for improving the electromechanical coupling coefficient and bandwidth of micromachined ultrasonic transducers, or MUTs, are presented as well as methods of manufacture of the MUTs improved by the presented methods.