Abstract: Provided is a piezoelectric device and an MEMS device whose size can be reduced. The piezoelectric device includes: a first substrate that includes a first surface on which a piezoelectric element and a first electrode coupled to the piezoelectric element are disposed; a second substrate that includes a second surface on which a second electrode configured to be coupled to a control circuit is disposed; and a third substrate that is disposed between the first substrate and the second substrate, and includes a third surface bonded to the first surface and a fourth surface facing the second surface, in which the third substrate has a through hole passing through from the third surface to the fourth surface, and a third electrode provided in the through hole and coupled to the first electrode, and the second electrode is coupled to the third electrode and is electrically coupled to the first electrode via the third electrode.

Abstract: A piezoelectric actuator includes an electrode layer including a trunk portion and a plurality of branch portions branched from the trunk portion. The trunk portion includes a plurality of junction points from each of which a corresponding branch portion of the plurality of branch portions are branched, an end spaced from the plurality of junction points, and a second through hole positioned between the plurality of junction points and the end of the trunk portion. A plurality of first through holes are grouped into a first group and a second group. The first group overlaps, in a first direction, a particular area defined between the end of the trunk portion and the second through hole and the second group overlaps, in the first direction, another particular area defined between the second through hole and the plurality of junction points.

Abstract: An acoustic resonator and a method of manufacturing the same are provided. The acoustic resonator includes a resonating part including a first electrode, a second electrode, and a piezoelectric layer; and a plurality of seed layers disposed on one side of the resonating part.

Abstract: A dielectric elastomer power generation system A1 includes a dielectric elastomer power generation element 3 having a dielectric elastomer layer 31 and a pair of electrode layers 32 sandwiching the dielectric elastomer layer 31. The dielectric elastomer power generation system A1 further includes a piezoelectric element 1 and a multi-stage voltage multiplier/rectifier circuit 2 that boosts and rectifies the voltage generated by the piezoelectric element 1 and applies the resulting voltage as an initial voltage to the dielectric elastomer power generation element 3. This configuration enables the system to be constructed at a lower cost and increase the amount of power generation.

Abstract: An electromechanical device comprising: first and second electrodes each comprising a metal layer; an active layer comprising at least one ferroelectric polymer and disposed between the first and the second electrode. The first electrode and the second electrode each comprise an interface layer comprising poly(3,4-ethylenedioxythiophene). Each interface layer is interposed between the active layer and the corresponding metal layer. The invention further relates to a method for manufacturing such a device.

Abstract: A sensor device that includes an integrated sensor assembly having a surface acoustic wave (SAW) sensor disposed on a piezoelectric substrate. The SAW sensor is adapted to measure an environmental condition of an environment in response to an RF signal. The SAW sensor includes an interdigitated transducer (IDT) formed on a substrate having at least a layer of a piezoelectric material. The SAW sensor includes either one or more SAW reflectors of a second IDT formed on the piezoelectric material. The SAW sensor further includes an RF antenna formed on the piezoelectric material. The SAW sensor and the RF antenna are integrated with one another on the piezoelectric material.

Abstract: A light-emitting module structure comprises a support substrate and a micro-module disposed on or in the support substrate that extends over only a portion of the support substrate. The micro-module comprises a rigid module substrate, an inorganic light-emitting diode, a power source, and a control circuit. The inorganic light-emitting diode, the power source, and the control circuit are disposed on or in the module substrate and the control circuit receives power from the power source to control the inorganic light-emitting diode to emit light. A light conductor is disposed on or in the support substrate and in alignment with the micro-module so that the inorganic light-emitting diode is disposed to emit light into the light conductor and the light conductor conducts the light beyond the micro-module to emit the light from the light conductor.

Abstract: A PMUT includes a substrate, a stopper, and a multi-layered structure, where the substrate includes a corner, and a cavity is disposed in the substrate. The stopper is in contact with the corner of the substrate and the cavity. The multi-layered structure is disposed over the cavity and attached to the stopper and the multi-layered structure includes at least one through hole in contact with the cavity.

Abstract: Ultrasound transducer assemblies and associated systems and method are disclosed herein. In one embodiment, an ultrasound transducer assembly includes at least one matching layer overlies a transducer layer. A plurality of kerfs extends at least into the matching layer. In some aspects, the kerfs are at least partially filled with a filler material that includes microballoons and/or microspheres.

Abstract: Laser-marked packaged surface acoustic wave devices are provided. The laser-marked packaged surface acoustic wave device may include a package structure encapsulating a surface acoustic wave device on a first side of a piezoelectric substrate. The opposite side of the piezoelectric substrate can be directly marked using a laser. The laser may be a deep ultraviolet laser. By directly marking the piezoelectric substrate itself, the use of a separate marking film can be avoided, making the packaged surface acoustic wave device thinner. When the laser has a wavelength readily absorbed by the piezoelectric substrate, a relatively shallow marking may be made in the piezoelectric substrate. The markings can extend less than 1 micrometer into the piezoelectric substrate, so as not to affect the structural integrity of the piezoelectric substrate or the operation of the packaged surface acoustic wave device.

Abstract: A piezoelectric actuator includes a square suspension plate, an outer frame, a plurality of brackets and a square piezoelectric ceramic plate. The outer frame is arranged around the suspension plate. A second surface of the outer frame and a second surface of the suspension plate are coplanar with each other. Each of the plurality of brackets has two ends, a first end is perpendicular to and connected with the suspension plate, and a second end is perpendicular to and connected with the outer frame for elastically supporting the suspension plate. Each bracket has a length in a range between 1.22 mm and 1.45 mm and a width in a range between 0.2 mm and 0.6 mm. A length of the piezoelectric ceramic plate is not larger than a length of the suspension plate. The piezoelectric ceramic plate is attached on a first surface of the suspension plate.

Abstract: An acoustic wave device includes a silicon oxide film, a lithium tantalate film, an IDT electrode, and a protection film that are laminated on a support substrate made of silicon. A wavelength normalized film thickness of a lithium tantalate film is denoted by TLT, an Euler angle is ?LT, a wavelength normalized film thickness of the silicon oxide film is TS, a wavelength normalized film thickness of the IDT electrode in terms of aluminum thickness is TE, a wavelength normalized film thickness of a protection film is TP, a propagation direction in the support substrate is ?Si, and a wavelength normalized film thickness of the support substrate is TSi. Values of TLT, ?LT, TS, TE, TP, and ?Si are set such that Ih corresponding to an intensity of a response of a spurious response represented by Formula (1) is greater than about ?2.4 in a spurious response.

Abstract: A resonance device that includes a MEMS substrate including a resonator, an upper lid, and a bonding portion bonding the MEMS substrate and the upper lid to seal a vibration space of the resonator. The bonding portion includes a eutectic layer containing a eutectic alloy as a main component thereof. The eutectic alloy is composed of a first metal containing aluminum as a main component thereof, a second metal of germanium or silicon, and a third metal of titanium or nickel.

Abstract: A resonance device that includes a lower cover, an upper cover joined to the lower cover, a resonator having vibrating arms that bend and vibrate in a vibration space between the lower cover and the upper cover, and particles attached to tip portions of the vibrating arms. When a median size of the particle is defined as D50, a specific gravity of the particle is defined as A, and a resonant frequency of the resonator is defined as X, D50?189/(X×?A).

Abstract: An ultrasonic device includes a base material that has an opening, a vibration plate that is provided on the base material and closes the opening, and a piezoelectric element that is provided on the vibration plate, in which the vibration plate has a first layer provided on the base material, and a second layer that is disposed between the first layer and the piezoelectric element and that suppresses diffusion of a component contained in the piezoelectric element, and a bending rigidity of the second layer is equal to or larger than a bending rigidity of the first layer.

Abstract: A micro-machined ultrasonic transducer is proposed. The micro-machined ultrasonic transducer includes a membrane element for transmitting/receiving ultrasonic waves, during the transmission/reception of ultrasonic waves the membrane element oscillating, about an equilibrium position, at a respective resonance frequency. The equilibrium position of the membrane element is variable according to a biasing electric signal applied to the membrane element. The micro-machined ultrasonic transducer further comprises a cap structure extending above the membrane element; the cap structure identifies, between it and the membrane element, a cavity whose volume is variable according to the equilibrium position of the membrane element. The cap structure comprises an opening for inputting/outputting the ultrasonic waves into/from the cavity. The cap structure and the membrane element act as tunable Helmholtz resonator, whereby the resonance frequency is variable according to the volume of the cavity.

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.