Growth of single crystals of lead zirconate titanate (PZT) and other perovskites is accomplished by liquid phase epitaxy onto a substrate of suitable structural and lattice parameter match. A solvent and specific growth conditions for stable growth are required to achieve the desired proportions of Zr and Ti.

A piezoelectric sensor, a manufacturing method thereof and an electronic device are provided. The piezoelectric sensor includes a substrate, an active layer, the active layer being disposed at a side of the substrate: a first electrode, the first electrode being disposed at a side of the active laver a wav from the substrate, and the first electrode including a plurality of sub-electrodes disposed at intervals: a piezoelectric layer, the piezoelectric layer being disposed at a side of the first electrode away from the active layer; and a second electrode, the second electrode being disposed at a side of the piezoelectric layer away from the first electrode. The active layer is configured to be capable of switching between an insulating state and a conducting state, and in the conducting state the active layer is capable of conducting the plurality of sub-electrodes.

A method for producing a ferroelectric polymer element includes: disposing one electrode on a substrate; applying polymer solution in which a polyvinylidene fluoride-based polymer is dissolved in a solvent including an aprotic polar solvent onto the one electrode by forme-based printing; firing the polymer solution to crystallize the polyvinylidene fluoride-based polymer, so that a ferroelectric layer is formed; and disposing the other electrode on the ferroelectric layer.

A method for forming a dielectric elastomer transducer of the present invention includes: a first electrode layer fixing step of fixing a first electrode layer to a target object; a dielectric elastomer layer fixing step of fixing a dielectric elastomer layer to the first electrode layer; and a second electrode layer fixing step of fixing a second electrode layer to the dielectric elastomer layer. This configuration ensures that the dielectric elastomer transducer highly conforms to the target object.

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.

Provided is a method for forming a ferroelectric film of a metal oxide having a fluorite-type structure at a low temperature of lower than 300° C., and a ferroelectric film obtained at a low temperature. The present invention provides a production method of a ferroelectric film comprising a crystalline metal oxide having a fluorite-type structure of an orthorhombic crystal phase, which comprises using a film sputtering method comprising sputtering a target at a substrate temperature of lower than 300° C., to deposit on the substrate a film of a metal oxide which is capable of having a fluorite-type structure of an orthorhombic crystal phase, and having a subsequent thermal history of said film of lower than 300° C.; or applying an electric field to said film after said deposition or after said thermal history of lower than 300° C. Also provided are the ferroelectric film, which is formed on an organic substrate, glass, or metal substrate, which can be used only at low temperatures, and a ferroelectric element and a ferroelectric functional element or device using the ferroelectric film.

A feature recognition structure provided by the embodiments of the present disclosure comprises: a plurality of first electrodes and a plurality of second electrodes disposed on a base substrate, wherein orthogonal projections of the plurality of first electrodes and of the plurality of second electrodes on the base substrate intersect each other to form a plurality of overlap regions; and a plurality of functional patterns disposed between one or more of the plurality of first electrodes and corresponding one or more of the plurality of second electrodes, wherein an orthogonal projection of each of the plurality of functional patterns on the base substrate is located in a corresponding one of the plurality of overlap regions; the functional patterns comprise at least one piezoelectric material, and have at least two types of sub-patterns, and different types of the sub-patterns have substantially different piezoelectric coefficients.

A method and structure for a transfer process for an acoustic resonator device. In an example, a bulk acoustic wave resonator (BAWR) with an air reflection cavity is formed. A piezoelectric thin film is grown on a crystalline substrate. Patterned electrodes are deposited on the surface of the piezoelectric film. An etched sacrificial layer is deposited over the electrodes and a planarized support layer is deposited over the sacrificial layer. The device can include temperature compensation layers (TCL) that improve the device TCF. These layers can be thin layers of oxide type materials and can be configured between the top electrode and the piezoelectric layer, between the bottom electrode and the piezoelectric layer, between two or more piezoelectric layers, and any combination thereof. In an example, the TCLs can be configured from thick passivation layers overlying the top electrode and/or underlying the bottom electrode.

A piezoelectric device includes: a base having at least one hole, a heat conductive portion disposed in the at least one hole and in contact with a wall of the at least one hole, and at least one piezoelectric sensor disposed on the base. A thermal conductivity of the heat conductive portion is greater than a thermal conductivity of the base. Each piezoelectric sensor includes: a first electrode, a piezoelectric pattern made of a piezoelectric material and a second electrode that are sequentially stacked in a thickness direction of the base.

A bulk acoustic wave (BAW) resonator includes a solidly mounted reflector, for example, a Bragg-type reflector, a piezoelectric layer, and first and second electrodes on first and second surfaces, respectively, of the piezoelectric layer. A filter device or filter system includes at least one BAW resonator. Related methods of fabrication include forming the BAW resonator.