An electromechanical transducer element includes a base substrate, a first electrode on the base substrate, a piezoelectric body on the first electrode, and a second electrode on the piezoelectric body. The base substrate has a void area opposite to the piezoelectric body via the first electrode, and a width of the void area on a cross section cut along a layer direction of the electromechanical transducer element satisfies 0.65≤Pw/Cw≤0.95, where Cw represents the width of the void area, and Pw represents a width of the piezoelectric body on the cross section.

A compact system for optimizing energy harvesting efficiency using of very thin (less than 10 μm thickness) PVDF films. The system is comprised of a flexible substrate such as polypropylene (PP) or Polydimethylsiloxane (PDMS) that supports PVDF thin films sandwiched between two aluminum electrode sheets. The PVDF films may be fabricated at different selected thicknesses by increasing spin rates. The PVDF films may also be fabricated in various different stacking arrangements in order to further allow the electrode to more efficiently produce energy.

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 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. A first patterned electrode is deposited on the surface of the piezoelectric film. An etched sacrificial layer is deposited over the first electrode and a planarized support layer is deposited over the sacrificial layer, which is then bonded to a substrate wafer. The crystalline substrate is removed and a second patterned electrode is deposited over a second surface of the film. The sacrificial layer is etched to release the air reflection cavity. Also, a cavity can instead be etched into the support layer prior to bonding with the substrate wafer. Alternatively, a reflector structure can be deposited on the first electrode, replacing the cavity.

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.

An object of the present invention is to improve the piezoelectricity of a PVT having the VDF ratio of 82 to 90% represented by a copolymer, in which copolymerization of vinylidene fluoride VDF and trifluoroethylene TrFe is 85 versus 15 (this is written as PVT85/15, and which is excellent in resistance to deformation, and heat resistance, etc. And therefore, it is also to obtain a piezoelectric film having piezoelectricity exceeding a PVT of less than 82 mol % of VDF represented by a PVT75/25, which conventionally shows the highest piezoelectricity, and a method of producing the same.

A piezoelectric film is made of a mixture of two kinds (for example, a first copolymer is PVT85/15 and a second copolymer is PVT75/25) having different polymerization ratios of vinylidene fluoride VDF and trifluoroethylene TrFE.

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.

An electroactive device may include a primary electrode, a secondary electrode overlapping at least a portion of the primary electrode, and a tertiary electrode overlapping at least a portion of the secondary electrode. The electroactive device may also include (i) a first electroactive polymer element including a first elastomer material disposed between and abutting the primary electrode and the secondary electrode, and (ii) a second electroactive polymer element including a second elastomer material disposed between and abutting the secondary electrode and the tertiary electrode. Various other devices, methods, and systems are also disclosed.

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 functional vehicle component and related methods include a functional leather assembly fixed over a vehicle component. The functional leather assembly includes a leather sheet, a flexible electronic circuit arranged on a first surface of the leather sheet that faces away from the vehicle component to thereby define an outermost surface of the leather sheet, and including a piezoelectric switch that can be actuated to make or break a conductive path in the circuit; and a pigmented coating arranged over the circuit. Upon actuation of the piezoelectric switch to make or break the conductive path in the circuit, the piezoelectric switch provides a haptic signal that indicates the actuation of the piezoelectric switch.