A method for preparing a piezoelectric film includes: coating a solution containing a piezoelectric polymer and a solvent on a substrate to obtain a film, wherein the piezoelectric polymer is a copolymer of vinylidene fluoride and trifluoroethylene; and annealing the film at a temperature ranging from 122° C. to 133° C., to obtain the piezoelectric film.

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.

A piezoelectric element includes a first electrode layer, a piezoelectric layer, and a second electrode layer. The first electrode layer, the piezoelectric layer, and the second electrode layer are stacked in sequence on one another. The first electrode layer has a first part overlapping the piezoelectric layer in a plan view, and a second part at least partially separated from the first part and not overlapping the piezoelectric layer in the plan view. The second electrode layer has a third part overlapping the piezoelectric layer in the plan view, and a fourth part separated from the third part. The fourth part is in contact with the first part and the second part.

A piezoelectric element includes a first electrode layer, a piezoelectric layer, and a second electrode layer. The first electrode layer, the piezoelectric layer, and the second electrode layer are stacked in sequence on one another. The first electrode layer has a first part overlapping the piezoelectric layer in a plan view, and a second part at least partially separated from the first part and not overlapping the piezoelectric layer in the plan view. The second electrode layer has a third part overlapping the piezoelectric layer in the plan view, and a fourth part separated from the third part. The fourth part is in contact with the first part and the second part.

A method for forming an electroactive device may include (i) depositing a curable material onto a primary electrode, (ii) curing the deposited curable material to form an electroactive polymer element comprising a cured elastomer material, and (iii) depositing an electrically conductive material onto a surface of the electroactive polymer element opposite the primary electrode to form a secondary electrode. The cured elastomer material may have a Poisson's ratio of between approximately 0.1 and approximately 0.35. Various other devices, methods, and systems are also disclosed.

There is disclosed a transducer and a method for generating the transducer. The transducer is formed on a substrate layer. The transducer includes a first electrode layer, a first piezoelectric layer on the first electrode layer, and a second electrode layer on the first piezoelectric layer. The first electrode layer is connected to a first electrical connector and the second electrode layer is connected to a second electrical connector. The transducer can be configured to act as an acoustic sensor or an electric potential sensor.

There is disclosed a transducer and a method for generating the transducer. The transducer is formed on a substrate layer. The transducer includes a first electrode layer, a first piezoelectric layer on the first electrode layer, and a second electrode layer on the first piezoelectric layer. The first electrode layer is connected to a first electrical connector and the second electrode layer is connected to a second electrical connector. The transducer can be configured to act as an acoustic sensor or an electric potential sensor.

A method of generating a piezoelectric actuator includes: forming a piezoelectric member upon a rigid substrate; and removing one or more portions of the rigid substrate to form one or more gaps in the rigid substrate, thus defining at least one deformable portion of the piezoelectric member and at least one rigid portion of the piezoelectric member.

A method of generating a piezoelectric actuator includes: forming a piezoelectric member upon a rigid substrate; and removing one or more portions of the rigid substrate to form one or more gaps in the rigid substrate, thus defining at least one deformable portion of the piezoelectric member and at least one rigid portion of the piezoelectric member.

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.