Abstract: An ultrasonic MEMS acoustic transducer formed in a body of semiconductor material having first and second surfaces opposite to one another. A first cavity extends in the body and delimits at the bottom a sensitive portion, which extends between the first cavity and the first surface of the body. The sensitive portion houses a second cavity and forms a membrane that extends between the second cavity and the first surface of the body. An elastic supporting structure extends between the sensitive portion and the body and is suspended over the first cavity.

Abstract: A brake mechanism for a brake caster is disclosed. In various embodiments, the brake mechanism includes a roller cylinder having a hollow interior and an inner cylindrical surface; a brake shaft disposed within the hollow interior of the roller cylinder and having an outer cylindrical surface; a piezoelectric disk disposed within the hollow interior of the roller cylinder; and a rotor disk disposed adjacent the piezoelectric disk.

Abstract: A surface acoustic wave device comprises a substrate and an interdigital transducer (IDT) electrode disposed on the substrate. The IDT electrode includes a lower electrode layer having a lower surface in contact with an upper surface of the substrate and an upper electrode layer having a lower surface defining a base in contact with an upper surface of the lower electrode layer. Side surfaces of the lower electrode layer are substantially perpendicular to the upper surface of the substrate. Side surfaces of the upper electrode layer are disposed at an acute angle relative to the upper surface of the substrate.

Abstract: An electro-acoustic resonator comprises a piezoelectric substrate on which an electrode structure is disposed. The electrode structure comprises a metal layer of aluminum and copper, a barrier layer forming a barrier against the diffusion of copper and another metal layer disposed on the barrier layer comprising aluminum. An AlCu intermetallic phase formed after an anneal is restricted to the portion beneath the barrier layer so that Galvano-corrosion of the electrode structure is avoided.

Abstract: Circuitry for estimating a displacement of a piezoelectric transducer in response to a drive signal applied to the piezoelectric transducer, the circuitry comprising: monitoring circuitry configured to be coupled to the piezoelectric transducer and to output a sense signal indicative of an electrical signal associated with the piezoelectric transducer as a result of the drive signal; wherein the circuitry is configured to generate a difference signal based on the drive signal and the sense signal; and wherein the circuitry further comprises processing circuitry configured to apply at least one transfer function to the difference signal to generate a signal indicative of the displacement of the piezoelectric transducer.

Abstract: A piezoelectric device includes a base portion and a membrane portion. The membrane portion is indirectly supported by the base portion, and is located on the upper side relative to the base portion. The membrane portion includes a plurality of layers. The membrane portion does not overlap with the base portion, and includes a single crystal piezoelectric layer, an upper electrode layer, and a lower electrode layer. The membrane portion is provided with a through-groove penetrating in the up-down direction. The through-groove includes a first step portion provided in the thickest layer among the plurality of layers defining the membrane portion. The width of the through-groove is narrower on a lower side than on an upper side with the first step portion as a boundary.

Abstract: An assembly including an electrical connection substrate formed of material having a Young's modulus of less than about 10 MPa, an acoustic device die having opposite end portions mounted on and electrically connected to the electrical connection substrate and a mold compound layer encapsulating the acoustic device die and interfacing with the substrate.

Abstract: A device includes a superconductor layer and a piezoelectric layer positioned adjacent to the superconductor layer. The piezoelectric layer is configured to apply a first strain to the superconductor layer in response to receiving a first voltage that is below a predefined voltage threshold and to apply a second strain to the superconductor layer in response to receiving a second voltage that is above the predefined voltage threshold. While the device is maintained below a superconducting threshold temperature for the superconductor layer and is supplied with current below a superconducting threshold current for the superconductor layer, the superconductor layer is configured to 1) operate in a superconducting state when the piezoelectric layer applies the first strain to the superconductor layer and 2) operate in an insulating state when the piezoelectric layer applies the second strain to the superconductor layer.

Abstract: Acoustic wave devices based on epitaxially grown heterostructures comprising appropriate combinations of epitaxially grown metallic transition metal nitride (TMN) layers, epitaxially grown Group III-nitride (III-N) piezoelectric semiconductor thin film layers, and epitaxially grown perovskite oxide (PO) layers. The devices can include bulk acoustic wave (BAW) devices, surface acoustic wave (SAW) devices, high overtone bulk acoustic resonator (HBAR) devices, and composite devices comprising HBAR devices integrated with high-electron-mobility transistors (HEMTs).

Abstract: A surface-launched acoustic wave sensor tag system for remotely sensing and/or providing identification information using sets of surface acoustic wave (SAW) sensor tag devices is characterized by acoustic wave device embodiments that include coding and other diversity techniques to produce groups of sensors that interact minimally, reducing or alleviating code collision problems typical of prior art coded SAW sensors and tags, and specific device embodiments of said coded SAW sensor tags and systems. These sensor/tag devices operate in a system which consists of one or more uniquely identifiable sensor/tag devices and a wireless interrogator. The sensor device incorporates an antenna for receiving incident RF energy and re-radiating the tag identification information and the sensor measured parameter(s). Since there is no power source in or connected to the sensor, it is a passive sensor. The device is wirelessly interrogated by the interrogator.

Abstract: An acoustic wave device uses a longitudinal acoustic wave, and includes a piezoelectric layer including first and second principal surfaces opposite to each other, an IDT electrode directly or indirectly on the first principal surface, and a high acoustic velocity member directly or indirectly on the second principal surface and including a 4H-type or 6H-type crystal polytype silicon carbide.

Abstract: Various methods and systems are provided for a multi-frequency transducer array. In one example, the transducer array includes an element formed of one or more sub-elements, at least one sub-element having a different resonance frequency. A frequency range of the transducer array may thereby be broadened.

Abstract: Provided in accordance with the herein described exemplary embodiments are piezo micro-machined ultrasonic transducers (pMUTs) each having a first electrode that includes a first electrode portion and a second electrode portion. The second electrode portion is separately operable from the first electrode portion. A second electrode is spaced apart from the first electrode and defines a space between the first electrode and the second electrode. A piezoelectric material is disposed in the space. Also provided are arrays of pMUTs wherein individual pMUTs have first electrode portions operably associated with array rows and second electrode portions operably associated with array columns.

Abstract: Planar phased ultrasound transducer including a first layer including a sheet of piezoelectric material, a piezo frame surrounding an outer perimeter of the sheet of piezoelectric material, and an epoxy material placed between the piezo frame and the sheet of piezoelectric material. The transducer includes a flex frame secured to a back side of the first layer.

Abstract: The present disclosure provides an acoustic transduction unit, a manufacturing method thereof and an acoustic transducer. The acoustic transduction unit includes a substrate, and a first electrode, a vibrating film and a second electrode sequentially arranged on the substrate, a cavity is formed between the first electrode and the vibrating film, orthographic projections of the first electrode, the cavity, the vibrating film and the second electrode on the substrate are at least partially overlapped with each other at a first overlapping region, and a hollowed-out pattern is formed in the vibrating film, and the orthographic projection of the hollowed-out pattern on the substrate and the orthographic projection of the cavity on the substrate are overlapped with each other, and the orthographic projection of the hollowed-out pattern on the substrate is distributed in a discontinuous manner around the first overlapping region.

Abstract: The present disclosure provides a high frequency surface acoustic wave resonator and a method for making the same. The high frequency surface acoustic wave resonator includes: a high wave velocity supporting substrate, a piezoelectric film disposed on a top surface of the high wave velocity supporting substrate, and a top electrode disposed on a top surface of the piezoelectric film; a velocity of a body wave propagating in the high wave velocity supporting substrate is greater than a velocity of a target elastic wave propagating in the piezoelectric film. The conductivity of the high wave velocity supporting substrate is greater than 1E3 ?·cm. The high frequency surface acoustic wave resonator and the method for making the same of the present disclosure solve the problem that the operating frequency of the traditional surface acoustic wave resonator is low.

Abstract: There are provided a method for manufacturing a substrate excellent in heat dissipation with a small loss in radio frequencies with no need of a high temperature process in which a metal impurity is diffused, and a substrate of high thermal conductivity. A composite substrate according to the present invention is a composite substrate having a piezoelectric single crystal substrate, a support substrate, and an intermediate layer provided between the piezoelectric single crystal substrate and the support substrate. The intermediate layer is a film formed of an inorganic material, and at least a part of the film is thermally synthesized silica. The intermediate layer may be separated into at least two layers along the bonding surface of the composite substrate. The first intermediate layer in contact with the support substrate may be a layer including thermally synthesized silica.

Abstract: Various embodiments include a mechanical amplification mechanism in a compact power unit of an electricity generator containing at least one piezoelectric element. The power units can be used singly but are also designed to be stacked, serially and/or in parallel with each other, and to be mounted within or under a substrate (e.g., a roadway or aircraft runway) such that the system achieves ultra-high-density of electricity production per unit area. Embodiments of the disclosed subject matter are therefore directed to a mechanical-to-electrical power generator, an accompanying power electronic-circuit, and power transmission and/or power saving into an energy-storage device. Therefore, the generated electrical power can be conditioned for, for example, transmitting to an electrical grid or for charging batteries of electrical vehicles. Other methods of formation of the power units and related systems are disclosed.

Abstract: A bonded body includes a supporting substrate; a piezoelectric material substrate composed of a material selected from the group consisting of lithium niobate, lithium tantalate and lithium niobate-lithium tantalate; and a bonding layer bonding the supporting substrate and piezoelectric material substrate and contacting a main surface of the piezoelectric material substrate. At least one of a bonding surface of the supporting substrate and a bonding surface of the piezoelectric material substrate, as measured by spectral ellipsometry with ? being assigned to a difference of phases of p-polarized light and s-polarized light of a reflected light, has a difference of the maximum and minimum values of the difference ? of the phases in a wavelength range of 400 nm to 760 nm of 70° or lower.

Abstract: A bonded body includes a supporting substrate; a piezoelectric material substrate composed of a material selected from the group consisting of lithium niobate, lithium tantalate and lithium niobate-lithium tantalate; and a bonding layer bonding the supporting substrate and the piezoelectric material substrate and contacting a main surface of the piezoelectric material substrate. It is provided that at least one of a bonding surface of the supporting substrate and a bonding surface of the piezoelectric material substrate is measured by X-ray reflectivity method and that 1 is assigned to a signal intensity in the case of total reflection. A relative intensity I of a reflected light from the bonding surface is approximated by the following formula (1) in a range of 1.0×10?4 or larger and 1.0×10?1 or smaller. I=a(2?)?b??(1) (? represents an incident angle of an X-ray with respect to the bonding surface, a is 1.0×10?5 or larger and 2.0×10?3 or smaller, and b is 5.0 or larger and 9.0 or smaller.