A piezoelectric element includes a piezoelectric body layer, a first electrode, a second electrode, a third electrode, and a conductor. The piezoelectric body layer has rectangular first and second principal surfaces opposing each other, and includes a piezoelectric material. The first electrode is provided on the first principal surface. The second electrode is provided on the first principal surface in such a way that the second electrode is separated from the first electrode. The third electrode is provided on the second principal surface in such a way that the third electrode opposes the first electrode. The conductor is connected to the second electrode and the third electrode. The first electrode has a round corner being rounder than a corner part of the piezoelectric body layer when seen in an opposing direction of the first and second principal surfaces.

The disclosure provides a piezoelectric element and a method for manufacturing a piezoelectric element. The disclosure provides the piezoelectric element comprising: a base layer, a piezoelectric layer which is disposed on one surface of the base layer, and in which upwardly curved convex portions and downwardly curved concave portions are continuously disposed along a first direction; and contact members which are disposed on the concave portions of the piezoelectric layer and on the one surface of the base layer to connect the piezoelectric layer to the base layer.

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.

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.

A piezo-resistor sensor includes a diffusion of a first conductivity type in a well of an opposite second type, contacts with islands in the diffusion, interconnects with the contacts, and a shield covers the diffusion between the contacts and extends over side walls of the diffusion between the contacts. Each interconnect covers the diffusion at the corresponding contact and extends over edges of the diffusion, and each island is at a side covered by its interconnect. A guard ring of the second type is around the diffusion. The shield covers the well between the diffusion and the ring and the edge of the ring facing the diffusion. If a gap between the shield and the interconnect is present, the ring bridges this gap, and/or the edges of the diffusion are completely covered by the combination of the shield and the interconnects.

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.

A radial type ultrasound transducer is arranged in an ultrasound endoscope including a bending portion on a distal end side of an insertion portion. The ultrasound transducer includes: a plurality of piezoelectric elements arranged at predetermined intervals in a circumferential manner and configured to transmit and receive ultrasound waves; a plurality of electrodes arranged in the respective piezoelectric elements; and a flexible printed circuit electrically connected to each of the electrodes. The flexible printed circuit includes a plurality of wires that extend such that at least parts of the wires cross a direction perpendicular to an arrangement direction of the piezoelectric elements, and the plurality of wires are electrically connected to the respective electrodes of the piezoelectric elements at positions where at least parts of the wires cross the direction perpendicular to the arrangement direction of the piezoelectric elements.

A piezoelectric component that has a piezoelectric element including a piezoelectric ceramic layer and a sintered metal layer on at least a first main surface of the piezoelectric ceramic layer and containing a non-precious metal, and a protective layer containing an elastic body covering first and second opposed main surfaces of the piezoelectric element. The piezoelectric ceramic layer contains 90 mol % or more of a perovskite compound that contains niobium, an alkali metal, and oxygen. A thickness of the piezoelectric element is 100 μm or less.

A method of manufacturing a semiconductor device includes: forming a first substrate includes a membrane stack over a first dielectric layer, the membrane stack having a first electrode, a second electrode over the first electrode and a piezoelectric layer between the first electrode and the second electrode, a third electrode over the first dielectric layer, and a second dielectric layer over the membrane stack and the third electrode; forming a second substrate, including: a redistribution layer (RDL) over a third substrate, the RDL having a fourth electrode; and a first cavity on a surface of the RDL adjacent to the fourth electrode; forming a second cavity in one of the first substrate and the second substrate; and bonding the first substrate to the second substrate.