A piezo-electric element includes a substrate; a lower electrode formed on the substrate; a piezo-electric film formed on the lower electrode; and an upper electrode formed on the piezo-electric film, wherein the upper electrode is formed on a surface on which a planarization process is performed.

An actuator device includes: an actuator including first contacts arranged in a first direction; and a wire member including second contacts and joined to the actuator. The second contacts are arranged in the first direction and respectively connected to the first contacts. Each of particular contacts as the first contacts or the second contacts has a protruding and recessed portion including: at least two protrusions; and a recess between the at least two protrusions. The particular contacts include: at least one central-region contact disposed on a central region in the first direction; and at least one end-region contact disposed nearer to an end region than to the central region in the first direction. The protruding and recessed portion of each of the at least one central-region contact is different in shape from the protruding and recessed portion of each of the at least one end-region contact.

A liquid ejection head includes a substrate in which a pressure generating chamber that communicates with a nozzle opening is formed; and a piezoelectric element having a piezoelectric layer, a first electrode that is formed on a surface of the piezoelectric layer on a side of the substrate so as to correspond to the pressure generating chamber, and a second electrode that is formed on a surface of the piezoelectric layer opposite to the side on which the first electrode is formed so as to extend over a plurality of the pressure generating chambers, wherein the second electrode is formed to extend to an outside of the pressure generating chamber in a longitudinal direction of the pressure generating chamber.

A sensor includes a first film, a first sensor portion, and a first element portion. The first film is deformable. The first sensor portion is provided at the first film. The first sensor portion includes a first magnetic layer, a second magnetic layer provided between the first film and the first magnetic layer, and a first intermediate layer provided between the first magnetic layer and the second magnetic layer. The first element portion includes a first piezoelectric layer fixed to the first film.

A structural health management system may include a structural health management apparatus including a carbon nanotube element configured to generate an electrical output in response to a deformation of the carbon nanotube element, a piezoelectric element configured to actuate in response to an electrical voltage applied to the piezoelectric element, electrode elements coupled to the carbon nanotube element and the piezoelectric element, and a controller communicatively coupled to the structural health management apparatus, wherein the controller is configured to convert the electrical output into data representing a measurement value of a structural abnormality and to initiate application of the electrical voltage to the piezoelectric element to counter the structural abnormality upon the measurement value being equal to or greater than a predetermined threshold value.

A piezoelectric element includes a first electrode, a second electrode, and a thin piezoelectric layer. The thin piezoelectric layer is provided between the first electrode and the first electrode, and is formed of a perovskite type compound oxide which contains potassium, sodium, and niobium. In the piezoelectric layer, in an X-ray diffraction pattern obtained by ??2? measurement, peaks derived from a (002) plane and a (200) plane are provided in a range in which 2? is from 45? to 47?, a peak position of the peak on a high angle side among the peaks satisfies 46.0??2??46.5?, and a difference of 2? between the peak on the high angle side and the peak on a low angle side is greater than 0.60?.

What is described is a MEMS device comprising a piezoelectric actuator, which includes a film of piezoelectric material. The film is penetrated by a plurality of holes.

An inkjet printing head 1 includes a piezoelectric element 6 having a lower electrode 7, a piezoelectric film 8 formed above the lower electrode 7, and an upper electrode 9 formed above the piezoelectric film 8, a hydrogen barrier film 13 covering an entirety of a side surface of the upper electrode 9 and the piezoelectric film 8, and an interlayer insulating film 14 that has an opening 17 at an upper surface center of the upper electrode 9, is laminated on the hydrogen barrier film 13, and faces the entirety of the side surface of the upper electrode 9 and the piezoelectric film 8 across the hydrogen barrier film 13.

A piezoelectric device comprising a substrate having a cavity, a piezoelectric film covering the cavity and being supported by the substrate, and electrodes disposed so as to sandwich the piezoelectric film. The piezoelectric film has a convex-shaped or concave-shaped vibrating region disposed on the cavity. The vibrating region is configured by a single-layer piezoelectric film including a first region composed of a first piezoelectric material and a second region composed of a second piezoelectric material having a piezoelectric constant larger than that of the first piezoelectric material. A first electrode and a second electrode are disposed so as to sandwich the second region of the piezoelectric film, a first input signal is converted to a first output signal based on displacement at the second region of the piezoelectric film between these electrodes, and a piezoelectric device comprising a convex-shaped vibrating region with high power and high sensitivity is provided.

An ultrasonic piezoelectric transducer device includes a transducer array consisting of an array of vibrating elements, and a base to which the array of vibrating elements in the transducer array are attached. The base include integrated electrical interconnects for carrying driving signals and sensed signals between the vibrating elements and an external control circuit. The base can be an ASIC wafer that includes integrated circuitry for controlling the driving and processing the sensed signals. The interconnects and control circuits in the base fit substantially within an area below the array of multiple vibrating elements.