In an angular velocity sensor, a pair of support parts are separated from each other in an x-axis direction in an orthogonal coordinate system xyz. A main part extends along the x-axis. A pair of extension parts connect two ends of the main part and inner sides of the support parts. The driving arms extend from the main part alongside each other in a y-axis direction separated from each other in the x-axis direction. The detecting arm extends from the main part in the y-axis direction at a position which is between the pair of driving arms. The driving circuit supplies voltages so that the pair of driving arms vibrate so as to bend to inverse sides from each other in the x-axis direction. The detecting circuit detects the signal generated due to bending deformation of the detecting arm in the z-axis direction.

An ultrasonic sensor includes a piezoelectric body including first and second surfaces. First and second electrodes are respectively provided on the first and second surfaces. The second electrode is opposed to the first electrode with the piezoelectric body interposed therebetween. A third electrode is provided on the second surface. The third electrode is spaced apart from the second electrode. The third electrode is electrically connected to the first electrode. When viewed from a thickness direction in which the first surface and the second surface are arranged, the second electrode extends to both end edges of the second surface in a first direction and is spaced apart from both end edges of the second surface in a second direction orthogonal to the first direction.

As a temperature measurement apparatus using a surface acoustic wave of a piezoelectric substrate that performs temperature measurement wirelessly and without power supply, the temperature measurement apparatus accurately measures the temperature of the thermocouple tip end by analyzing the frequency characteristics of the surface acoustic wave propagating on the piezoelectric substrate and including temperature information of the piezoelectric substrate, and detecting change in propagation time of the surface acoustic wave of the piezoelectric substrate that is changed by the electromotive force of the thermocouple.

An electronic device includes a substrate layer having a front surface and a back surface opposite the front surface, a plurality of ultrasonic transducers formed on the front surface of the substrate layer, wherein the plurality of ultrasonic transducers generate backward waves during operation, the backward waves propagating through the substrate layer, and a plurality of substrate structures formed within the back surface of the substrate layer, the plurality of substrate structures configured to modify the backward waves during the operation.

A piezoelectric actuator includes a first electrode, a first piezoelectric body disposed at one side of the first electrode in a thickness direction of the first electrode, an individual electrode disposed at one side of the first piezoelectric body in the thickness direction, a second piezoelectric body disposed at one side of the individual electrode in the thickness direction, a second electrode disposed at one side of the second piezoelectric body in the thickness direction, a wiring that electrically connects to the individual electrode, a first contact, and a second contact. At the first and the second contacts, the first electrode and the second electrode electrically connect to each other. The first contact is disposed at one side of the individual electrode in a perpendicular direction perpendicular to the thickness direction. The second contact is disposed at the other side of the individual electrode in the perpendicular direction.

A micro crystal oscillator includes: a tank body including a tank bottom and a side wall, the tank bottom including an inner surface and an outer surface, wherein the side wall is disposed on a periphery of the inner surface of the tank bottom to form a recess together with the tank bottom; a plurality of patterned electrodes arranged on the outer surface; a first patterned circuit arranged on the side wall; a plurality of vias disposed in the tank body for electrically connecting at least one of the patterned electrodes to the first patterned circuit; an oscillating chip arranged on the inner surface and located in the recess; and a plurality of connecting wires located in the recess and respectively connected to the oscillating chip and the first patterned circuit in a wire bonding manner; wherein the micro crystal oscillator is of millimeter level.

In some embodiments, a piezoelectric device is provided. The piezoelectric device includes a semiconductor substrate. A first electrode is disposed over the semiconductor substrate. A piezoelectric structure is disposed on the first electrode. A second electrode is disposed on the piezoelectric structure. A heating element is disposed over the semiconductor substrate. The heating element is configured to heat the piezoelectric structure to a recovery temperature for a period of time, where heating the piezoelectric structure to the recovery temperature for the period of time improves a degraded electrical property of the piezoelectric device.

Provided is an energy conversion film excellent in charge retention performance and suppressed in deterioration of piezoelectricity even if it is exposed to a high temperature environment and an energy conversion element and the like using the film. An energy conversion element comprising: an energy conversion film at least comprises a charged resin film consisting of a resin film at least containing a thermoplastic resin and a metal soap; and an electrode provided on at least one of the two surfaces of the energy conversion film.

A piezoelectric micromachined ultrasound transducer (PMUT) array may comprise PMUT devices with respective piezoelectric layers and electrode layers. Parasitic capacitance can be reduced when an electrode layer is not shared across PMUT devices but may expose the devices to electromagnetic interference (EMI). A conductive layer located within the structural layer or on a shared plane with the electrode layers may reduce EMI affecting the PMUT array operation.

A piezoelectric actuator comprises a substrate, an insulator layer on the substrate, and a piezo actuator stack on the insulator layer. The piezo actuator stack comprises an insulator-adjacent electrode on the insulator layer. A piezo layer having a tapered sidewall resides on a portion of the insulator-adjacent electrode. An insulator-distal electrode on the piezo layer having a taper-adjacent edge offset from an intersection of the tapered sidewall of the piezo layer and the insulator-adjacent electrode.