Abstract: An acoustic wave resonator comprises a piezoelectric material formed of aluminum nitride (AlN) doped with calcium (Ca) to enhance performance of the acoustic wave resonator.

Abstract: A piezoelectric resonator includes a vibrating part having a pair of principal surfaces in an obverse-reverse relationship, and a side surface configured to couple the pair of principal surfaces to each other, and a protruding part which is provided to the vibrating part, and is configured to transmit a drive force generated by a vibration of the vibrating part to a driven part, wherein the vibrating part has a pair of vibrating plates including a first vibrating plate and a second vibrating plate stacked on one another in afirst direction in which the pair of principal surfaces are arranged side by side, the first vibrating plate has a flexural vibrating piezoelectric element configured to flexurally vibrate the vibrating part in a third direction perpendicular to a second direction in which the driven part and the protruding part are arranged side by side in a plan view of the principal surfaces, either one or both of the first vibrating plate and the second vibrating plate have a stretching vibrating piezo

Abstract: A bulk acoustic wave resonator includes a substrate, a support layer disposed on the substrate, the support layer including a cavity having a polygon shape with more than three sides in a plane crossing a first direction from the substrate to the support layer, a piezoelectric layer disposed on the support layer, a bottom electrode disposed below the piezoelectric layer, partially overlapping the cavity, and extending across a first side of the cavity, and a top electrode disposed above the piezoelectric layer, partially overlapping the cavity, and extending across a second side of the cavity. The bulk acoustic wave resonator further includes at least one release hole formed in the piezoelectric layer and overlapping a portion of the cavity.

Abstract: A multilayer piezoelectric element includes a ceramic body formed by a piezoelectric ceramic, and having first and second end face facing a longitudinal direction, first and second principal faces facing a thickness direction perpendicular to the longitudinal direction. A pair of external electrodes cover the first and second end faces, extend from the first and second end faces onto the first principal face via ridge parts connecting the end faces with the principal faces, and project in the thickness direction on the first principal face. Multiple internal electrodes are stacked inside the ceramic body and are connected alternately to the pair of external electrodes along the thickness direction. A surface electrode is provided on at least one of the first and second principal faces, and connected to the external electrode different from the one to which the internal electrode adjacent in the thickness direction is connected.

Abstract: A piezoelectric device includes a diaphragm provided on a side of one surface of a substrate, and a piezoelectric actuator having a first electrode, a piezoelectric body layer, and a second electrode which are stacked in a first direction on a side of a surface opposite to the substrate of the diaphragm, in which when one area far from an end portion of the second electrode is a first area and one area near the end portion of the second electrode is a second area, of two areas of the second electrode in a second direction intersecting the first direction, the second electrode has a stiffness of 17,000 N/m or more in the second area in the first direction, which is higher than a stiffness in the first area in the first direction, and a length in the second area in the first direction is equal to or less than a length of the piezoelectric body layer in the second area in the first direction.

Abstract: A production method for a surface acoustic wave device comprises the following steps: a step of providing a piezoelectric substrate comprising a transducer arranged on the main front face; a step of depositing a dielectric encapsulation layer on the main front face of the piezoelectric substrate and on the transducer; and a step of assembling the dielectric encapsulation layer with the main front face of a support substrate having a coefficient of thermal expansion less than that of the piezoelectric substrate. In additional embodiments, a surface acoustic wave device comprises a layer of piezoelectric material equipped with a transducer on a main front face, arranged on a substrate support of which the coefficient of thermal expansion is less than that of the piezoelectric material. The transducer is arranged in a dielectric encapsulation layer, between the layer of piezoelectric material and the support substrate.

Abstract: Provided is a piezoelectric ceramics including crystal grains each including: a first region that is formed of a perovskite-type metal oxide having a crystal structure in which a central element of a unit cell is located at an asymmetrical position; and a second region that is formed of a perovskite-type metal oxide having a crystal structure in which a central element of a unit cell is located at a symmetrical position, and that is present inside the first region, wherein a ratio of a cross-sectional area of the second region to a cross-sectional area of the piezoelectric ceramics is 0.1% or less.

Abstract: A bulk acoustic wave filter includes: a first bulk acoustic wave resonator including, in an order from bottom to top, a first cavity, a first bottom electrode, a first segment of a piezoelectric layer, and a first top electrode; a second bulk acoustic wave resonator disposed adjacent to the first bulk acoustic wave resonator, and including, in the order from bottom to top, a second cavity, a second bottom electrode, a second segment of the piezoelectric layer, and a second top electrode; a boundary structure surrounding the first cavity and the second cavity, the boundary structure including a boundary portion extending between and separating the first cavity and the second cavity, and the boundary portion being disconnected at a disconnection region; and a first release hole formed in the piezoelectric layer, and overlapping the disconnection region.

Abstract: A front-end module (FEM) for a 6.1 GHz Wi-Fi acoustic wave resonator RF filter circuit. The device can include a power amplifier (PA), a 6.1 GHz resonator, and a diversity switch. The device can further include a low noise amplifier (LNA). The PA is electrically coupled to an input node and can be configured to a DC power detector or an RF power detector. The resonator can be configured between the PA and the diversity switch, or between the diversity switch and an antenna. The LNA may be configured to the diversity switch or be electrically isolated from the switch. Another 6.1 GHZ resonator may be configured between the diversity switch and the LNA. In a specific example, this device integrates a 6.1 GHz PA, a 6.1 GHZ bulk acoustic wave (BAW) RF filter, a single pole two throw (SP2T) switch, and a bypassable LNA into a single device.

Abstract: The present invention relates to a filter circuit (100) comprising a first and a second bulk acoustic wave resonator (2, 3), the first resonator (2) having a first piezoelectric layer (4) structured such that the first resonator (2) has a lower resonant frequency than the second resonator (3), wherein the first piezoelectric layer (4) is structured by recesses (14) passing through the first piezoelectric layer (4), the first resonator (2) and the second resonator (3) as series resonators (102, 105) connected in series with a signal path of the filter circuit (100) or wherein the first resonator (2) and the second resonator (3) as parallel resonators (103, 106) are connected to the signal path of the filter circuit (100) in such a way that in each case one electrode of the resonators is connected to the signal path.

Abstract: A bulk-acoustic wave resonator includes a substrate, a first electrode disposed on the substrate, a piezoelectric layer, of which at least a portion is disposed on the first electrode, a second electrode disposed on the piezoelectric layer, and a passivation layer disposed to cover the first electrode and the second electrode. Either one or both of the first electrode and the second electrode includes an aluminum alloy layer. Either one or both of the piezoelectric layer and the passivation layer has aluminum nitride, or aluminum nitride added with a doping material, having a ratio of an out-of-plane lattice constant “c” to an in-plane lattice constant “a” (c/a) of less than 1.58.

Abstract: A ladder filter comprises a plurality of series arm bulk acoustic wave resonators electrically connected in series between an input port and an output port of the ladder filter and a plurality of shunt bulk acoustic wave resonators electrically connected in parallel between adjacent ones of the plurality of series arm bulk acoustic wave resonators and ground, at least one of the plurality of shunt bulk acoustic wave resonators including raised frame regions having a first width, at least one of the plurality of series arm bulk acoustic wave resonators having one of raised frame regions having a second width less than the first width or lacking raised frame regions.

Abstract: A high Q acoustic BAW resonator with high coupling and improved spurious mode suppression is given. The BAW resonator comprises an active resonator region (AR) formed by an overlap of the three layers bottom electrode (BE), piezoelectric layer (PL) and top electrode layer (TE). An inner-flap (IF) is formed by a dielectric 3D structure sitting on a marginal region (MR) of the active resonator region (AR) or adjacent thereto, extending inwardly towards the center thereof and having a section that runs in parallel and distant to the top surface of the resonator keeping an inner gap (IG) thereto or an angle ?.

Abstract: A bulk-acoustic wave resonator includes: a substrate; a lower electrode disposed on the substrate; a piezoelectric layer at least partially covering the lower electrode; and an upper electrode at least partially covering the piezoelectric layer. On a surface of the bulk-acoustic wave resonator, a centroid of an active area in which the lower electrode, the piezoelectric layer, and the upper electrode all overlap each other is aligned with a center of a rectangle defining an aspect ratio of the active area. The active area has a shape of a polygon symmetrical with respect to at least one axis passing through the center of the rectangle defining the aspect ratio. The aspect ratio is greater than or equal to 2 and less than or equal to 10.

Abstract: A bulk-acoustic wave resonator includes: a substrate; a seed layer disposed on the substrate, and having a hexagonal crystal structure; a bottom electrode disposed on the seed layer; a piezoelectric layer at least partially disposed on the bottom electrode; and a top electrode disposed on the piezoelectric layer, wherein either one or both of the bottom electrode and the top electrode includes a scandium (Sc)-containing aluminum alloy layer.

Abstract: A liquid discharge head to discharge a liquid includes a piezoelectric body, a first electrode layer disposed at least partly on the piezoelectric body in a stacking direction, and a first wiring disposed on the first electrode layer in the stacking direction, the first wiring being more likely to cause ion migration than the first electrode layer, in which the piezoelectric body, the first electrode layer, and the first wiring are stacked in the stacking direction. When a predetermined area on the piezoelectric body is a first area, and a predetermined area adjacent to the first area on the piezoelectric body is a second area, both the first wiring and the first electrode layer are disposed in the first area, and the first wiring is not disposed while the first electrode layer is disposed in the second area.

Abstract: Methods for forming a film bulk acoustic resonator (FBAR) are provided. In the method, formation of several mutually overlapped and hence connected sacrificial material layers above and under a resonator sheet facilitates the removal of the sacrificial material layers. Cavities left after the removal overlap at a polygonal area with non-parallel sides. This reduces the likelihood of boundary reflections of transverse parasitic waves causing standing wave resonance in the FBAR, thereby enhancing its performance in parasitic wave crosstalk. Further, according to the disclosure, the FBAR is enabled to be integrated with CMOS circuitry and hence exhibits higher reliability.

Abstract: A resonator device includes a quartz crystal substrate, a resonator element including a first excitation electrode arranged on a first surface of the quartz crystal substrate, a second excitation electrode arranged on a second surface of the quartz crystal substrate in opposition to the first excitation electrode, and first and second pad electrodes that are arranged on the first surface and are coupled to the first and second excitation electrodes, a base including a substrate and first and second interconnects arranged on the substrate, a first bonding member bonding the first pad electrode to the first interconnect, and a second bonding member bonding the second pad electrode to the second interconnect. The first and second bonding members are arranged such that a first imaginary line that passes through a centroid of the resonator element and is parallel to an X axis is interposed between the first and second bonding members.

Abstract: The present disclosure provides a tensile force detecting device including a piezoelectric element to generate an electrical signal by a load, the elastic thread connected to the piezoelectric element to support the load applied to the piezoelectric element, and a sewing thread connected to the piezoelectric element to transmit the load to the piezoelectric element.

Abstract: An artificial tongue is provided. The artificial tongue includes tongue tissue formed by a bioprinting process, an antenna embedded within the tongue tissue and configured to wirelessly receive power from an external device, a processor embedded within the tongue tissue and operatively coupled to the antenna, and a piezoelectric element embedded within the tongue tissue and operatively coupled to the processor. The piezoelectric element is configured to deform in response to an applied electric bias, and the processor is configured to cause the electric bias to be applied to the piezoelectric element based on the power received by the antenna.

Abstract: An ultrasonic transducer includes a carrier with a first surface and a second surface which are opposite to each other, a piezoceramic element attached on the first surface of the carrier, a first acoustic matching layer with a third surface and a fourth surface which are opposite to each other, the third surface is attached on the second surface of the carrier, wherein the first acoustic matching layer includes a mesh with openings, and the thickness of first acoustic matching layer is smaller than ¼ wavelength of an ultrasonic wave emitted by the piezoceramic element in the first acoustic matching layer in an operating frequency, and a total area of the openings of mesh is larger than 30% area of the third surface of first acoustic matching layer, and a second acoustic matching layer disposed on the fourth surface of the first acoustic matching layer.

Abstract: A backing includes a plurality of backing plates that are laminated. Each backing plate includes a lead row and a backing material. Each lead includes a lead wire and an insulating coating. The insulating coating is integrated with the backing material, and an adhesive layer between them does not exist. Short-circuit between the leads may be prevented or reduced by the insulating coating. The backing plate is manufactured by a screen printing method.

Abstract: A tactile reproduction device, a method for driving the same, and a tactile reproduction apparatus. Tactile reproduction device may simulate textures to implement tactile reproduction. tactile reproduction device includes a plurality of piezoelectric units, includes: first electrode, piezoelectric section, and second electrode which are laminated, wherein the second electrode includes: first comb electrode and second comb electrode; the first comb electrode includes: a plurality of first comb-teeth electrodes and a first comb-shank electrode connecting the plurality of first comb-teeth electrodes; the second comb electrode includes: a plurality of second comb-teeth electrodes and a second comb-shank electrode connecting the plurality of second comb-teeth electrodes; the plurality of first comb-teeth electrodes and the plurality of second comb-teeth electrodes are mutually intersected; the first electrode includes a plurality of electrode units which are not connected to each other.

Abstract: An acoustic wave device includes a piezoelectric substrate, a pair of interleaved interdigital transducer electrodes disposed on the piezoelectric substrate, and a dielectric film including silicon oxynitride covering the pair of interleaved interdigital transducer electrodes. The dielectric film exhibits a temperature coefficient of velocity of substantially zero throughout an operating temperature range of the acoustic wave device of between ?55° C. and 125° C.

Abstract: There is provided a piezoelectric actuator, including: a vibration plate; a first piezoelectric body; a second piezoelectric body; a first electrode disposed on a first surface of the first piezoelectric body; a second electrode disposed on a second surface of the second piezoelectric body; an intermediate electrode disposed on an intermediate surface of the first piezoelectric body and overlapping with the first and second electrodes; an intermediate trace connected to the intermediate electrode on the intermediate surface and drawn out to one side in a first direction beyond the first piezoelectric body and the second piezoelectric body; a first trace overlapping with the intermediate trace in the thickness direction and being conducted with the intermediate trace; and a second trace overlapping with the intermediate trace in the thickness direction and being conducted with the intermediate trace.

Abstract: 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.

Abstract: A piezoelectric actuator assembly is described. The assembly including a first layer including a top and a bottom surfaces. The assembly including a second layer having a top and a bottom surfaces, the bottom surface of the second layer is disposed over the top surface of the first layer. The assembly including a third layer having a top and a bottom surfaces, the bottom surface of the third layer is disposed over the top surface of the second layer. The assembly includes a first electrode, a second electrode, a third electrode, and a fourth electrode. The third electrode is configured to be shorter than the second electrode such that the active PZT length of the second layer and the third layer is shorter than the active PZT length of the first layer.

Abstract: The present disclosure provides a fingerprint recognition module, a driving method thereof, a manufacturing method thereof, and a display device. The fingerprint recognition module includes a receiving electrode layer, a piezoelectric material layer, and a driving electrode layer. The receiving electrode layer includes a plurality of receiving electrodes arranged in an array along a first direction and a second direction. The piezoelectric material layer is disposed on a side of the receiving electrode layer. The driving electrode layer is disposed on a side of the piezoelectric material layer remote from the receiving electrode layer and includes a plurality of driving electrodes arranged along the second direction. Each driving electrode is a strip electrode extending along the first direction, and overlaps with multiple receiving electrodes arranged along the first direction.

Abstract: Vertical packaging configurations for ultrasound chips are described. Vertical packaging may involve use of integrated interconnects other than wires for wire bonding. Examples of such integrated interconnects include edge-contact vias, through silicon vias and conductive pillars. Edge-contact vias are vias defined in a trench formed in the ultrasound chip. Multiple vias may be provided for each trench, thus increasing the density of vias. Such vias enable electric access to the ultrasound transducers. Through silicon vias are formed through the silicon handle and provide access from the bottom surface of the ultrasound chip. Conductive pillars, including copper pillars, are disposed around the perimeter of an ultrasound chip and provide access to the ultrasound transducers from the top surface of the chip. Use of these types of packaging techniques can enable a substantial reduction in the dimensions of an ultrasound device.

Abstract: Provided is a piezoelectric substrate including: an elongate conductor; and an elongate first piezoelectric material helically wound in one direction around the conductor, in which the first piezoelectric material includes an optically active helical chiral polymer (A), the lengthwise direction of the first piezoelectric material and the principal orientation direction of the helical chiral polymer (A) included in the first piezoelectric material are substantially parallel to each other, and the first piezoelectric material has an orientation degree of F. in a range of from 0.5 to less than 1.0, determined from X-ray diffraction measurement by the following Formula (a): orientation degree F.=(180°??)/180°??(a) (in Formula (a), ? represents a half width of a peak derived from orientation).

Abstract: A piezoelectric substrate, comprising: a conductor cord that has a core material and a conductor disposed around the core material; and an elongated piezoelectric body that is disposed around the conductor cord in a spiral manner, unidirectionally along an axial direction of the conductor cord, wherein: the piezoelectric body comprises an optically active helical chiral polymer, a lengthwise direction of the piezoelectric body and a main orientation direction of the helical chiral polymer in the piezoelectric body are substantially parallel to each other, the piezoelectric body has an orientation degree F. of from 0.5 to less than 1.0, and the conductor cord satisfies Formula (b): ?Dmax<tpmin, wherein ?Dmax is a maximum value of a difference in height between a division A that is selected from plural divisions and a division B that is adjacent to the division A, and tpmin is a minimum thickness of the piezoelectric body.

Abstract: An actuator device includes: an actuator including piezoelectric elements arranged in a first direction and first contacts arranged in the first direction; a protector including a first wall opposed to the piezoelectric elements and a second wall coupled to the first wall and joined to a region of the actuator at which the first contacts are disposed; first connection terminals disposed on the first; and first through electrodes formed in the second wall to bring the first contacts and the first connection terminals into conduction with each other. A distance between two of the first through electrodes which respectively correspond to two of the piezoelectric elements which are adjacent to each other in the first direction is greater than a distance in the first direction between the two of the piezoelectric elements which are adjacent to each other in the first direction.

Abstract: A thin-film piezoelectric-material element includes a laminated structure part having a lower electrode film, a piezoelectric-material film laminated on the lower electrode film and an upper electrode film laminated on the piezoelectric-material film. The piezoelectric-material film includes a size larger than the upper electrode film, a riser end-surface and step-surface formed on a top-surface of the upper electrode film side. The riser end-surface connects smoothly with a peripheral end-surface of the upper electrode film and vertically intersects with the top-surface. The step-surface intersects vertically with the riser end-surface.

Abstract: A method of manufacturing an electrode assembly includes positioning a layer stack comprising an electrode positioned between an electrode insulator and a support polymer in a vacuum bag, removing air from the vacuum bag thereby vacuum coupling the electrode to the electrode insulator, and removing the layer stack from the vacuum bag, where upon removal of the layer stack from the vacuum bag, the electrode remains vacuum coupled to the electrode insulator and the electrode insulator is in direct contact with the electrode, thereby forming an electrode assembly.

Abstract: A piezoelectric transformer that includes a vibration portion assembly having an output electrode, an output-side intermediate electrode, an input-side intermediate electrode, and an input electrode. The vibration portion assembly includes n vibration portions. The input electrode includes one to n input electrode pieces. The output electrode includes one to n output electrode pieces. Wiring lines are arranged such that voltages of opposite phases can be respectively applied to a first input electrode piece group of the input electrode pieces corresponding to odd-numbered vibration portions, and a second input electrode piece group of the input electrode pieces corresponding to even-numbered vibration portions. The second output electrode piece and the first output-side intermediate electrode piece are superposed with each other in the thickness direction.

Abstract: A dielectric elastomer driving sensor system includes: a dielectric elastomer transducer portion including a dielectric elastomer layer and a pair of electrode layers that sandwich the dielectric elastomer layer, where the pair of electrode layers include a driving region and a sensor region that are partitioned from each other; a power supply unit that applies a voltage to the driving region; a detection unit that detects a change in capacitance in the sensor region; and a control unit that controls the power supply unit and the detection unit. With this configuration, both the driving function and the sensor function can be performed.

Abstract: An electro-mechanical transducer includes a diaphragm plate on a substrate, a first electrode on the diaphragm plate, an electro-mechanical transducer film on the first electrode, and a second electrode on the electro-mechanical transducer film. One of the first electrode and the second electrode is a common electrode. Another of the first electrode and the second electrode is an individual electrode. At least a portion of the common electrode is laminated on and in contact with the diaphragm plate. The common electrode has a plurality of holes penetrating the common electrode in a lamination direction.

Abstract: An electrical connection structure for connecting a piezoelectric element and an electrical circuit to each other with a conductive adhesive is described. The electrical connection structure includes an epoxy, a conductive component surrounded by the epoxy, and a trace feature implemented on top of the electrical connection structure.

Abstract: A hybrid ultrasonic transducer and a method of manufacturing the same are provided. A method of manufacturing a semiconductor device includes the forming of a first substrate and a second substrate. The forming of the first substrate includes: depositing a membrane stack over a first dielectric layer; forming a third electrode over the first dielectric layer; and depositing a second dielectric layer over the membrane stack and the third electrode. The forming of the second substrate includes: forming a redistribution layer (RDL) having a fourth electrode; and etching a first cavity on a surface of the RDL adjacent to the fourth electrode. The method further includes: forming a second cavity in one of the first substrate and the second substrate; and bonding the first substrate to the second substrate.

Abstract: The present disclosure relates to electrically controllable surgical tools. In general, surgical devices are provided having an electrically controllable, fingered operating end for use in angiography, endovascular and/or neurological surgery. The finger(s) at the operating end can be made from ionic polymer metal composite (IPMC) material to facilitate control of the finger(s).

Abstract: A method for manufacturing a pressure-sensitive sensor includes providing an extruder that includes a cylindrical die, a mandrel arranged inside the die and having plural helical grooves on an outer circumferential surface, and an annular outlet sandwiched between the die and the mandrel, and by using the extruder, performing simultaneous extrusion-molding of an elastic insulating material and an elastic conductive material by supplying the elastic conductive material into not less than two of the grooves from the inside of the mandrel while extruding the elastic insulating material, so as to form a pressure-sensitive sensor. The sensor includes a tubular body including an elastic insulation and having a hollow portion along a longitudinal direction, and not less than two conductive ribs including an elastic conductor and helically provided along an inner circumferential surface of the hollow portion of the tubular body so as to protrude inward from the inner circumferential surface.

Abstract: A piezoelectric thin film resonator includes: a substrate; a piezoelectric film located on the substrate; a lower electrode and an upper electrode facing each other across at least a part of the piezoelectric film; and a wiring layer located on the upper electrode, the wiring layer having a thickness equal to or greater than 0.8 ?m and equal to or less than 3.0 ?m, at least a part of the wiring layer overlapping in plan view with a resonance region in which the lower electrode and the upper electrode face each other across the piezoelectric film, a distance between an outline of the resonance region and an edge of a lower surface located within the resonance region and farthest from the outline being greater than 0 ?m and less than 2 ?m.

Abstract: A liquid ejecting head includes a flow path forming substrate in which a pressure generating chamber which communicates with a nozzle which ejects a liquid is formed by a partitioning wall, and a piezoelectric actuator in which a first electrode, a piezoelectric layer, and a second electrode are laminated, in which the piezoelectric layer includes a region which is interposed between the first electrode and the second electrode in a lamination direction, and in which when viewed in plan view from the lamination direction, the region overlaps at least a portion of the edges of each side of an opening of the pressure generating chamber on the piezoelectric actuator side and does not overlap one of the first electrode and the second electrode in at least a portion of the opening.

Abstract: A bulk acoustic wave resonator device includes: a substrate; a lower electrode disposed on the substrate; a piezoelectric layer disposed over a portion of the lower electrode; an upper electrode disposed on the piezoelectric layer; and a shape control layer covering an edge of a cavity disposed between the substrate and the lower electrode, wherein tensile stress is applied to the shape control layer during formation of the shape control layer.

Abstract: A multi-layer ceramic capacitor includes: a multi-layer unit including a capacitance forming unit including internal electrodes laminated in a first direction, a drawn portion extending from the capacitance forming unit in a second direction, and a cover that covers the capacitance forming unit and the drawn portion in the first direction, the multi-layer unit having a main surface facing in the first direction, an end surface facing in the second direction, and a side surface facing in a third direction; and a side margin provided to the side surface, the side surface including a first straight portion including an outer edge of the main surface and extending in the second direction, a second straight portion including an outer edge of the end surface and extending in the first direction, and a corner portion that connects the first and second straight portions with each other, the corner portion being curved.

Abstract: A method for fabricating bulk acoustic wave resonator with mass adjustment structure, comprising following steps of: forming a sacrificial structure mesa on a substrate; etching the sacrificial structure mesa such that any two adjacent parts have different heights, a top surface of a highest part of the sacrificial structure mesa is coincident with a mesa top extending plane; forming an insulating layer on the sacrificial structure mesa and the substrate; polishing the insulating layer to form a polished surface; forming a bulk acoustic wave resonance structure including a top electrode, a piezoelectric layer and a bottom electrode on the polished surface; etching the sacrificial structure mesa to form a cavity; the insulating layer between the polished surface and the mesa top extending plane forms a frequency tuning structure, the insulating layer between the mesa top extending plane and the cavity forms a mass adjustment structure.

Abstract: A transducer that converts electrical energy to mechanical energy, the transducer includes a dielectric layer; a first electrode that is provided on one surface of the dielectric layer; and a second electrode that is provided on another surface of the dielectric layer. At least one of the first electrode and the second electrode becomes an insulator, before the dielectric layer suffers insulation breakdown by voltage that is applied between the first electrode and the second electrode.

Abstract: A crystal resonator includes a flat plate-shaped crystal element and excitation electrodes. The crystal element has principal surfaces parallel to an X?-axis and a Z?-axis. The X?-axis is an axis of rotating an X-axis in a range of 15 to 25 degrees around a Z-axis. The Z?-axis is an axis of rotating the Z-axis in a range of 33 to 35 degrees around the X?-axis. The excitation electrodes are formed on the respective principal. The excitation electrodes include a first region with a circular outer shape and a second region. The second region is formed at a peripheral area of the first region. The second region has a thickness thinner than the first region and has an elliptical outer shape. The elliptical shape has a long axis extending in a direction in a range of ?5 to +15 degrees with respect to a direction that the X?-axis extends.

Abstract: An electronic device such as a pair of headphones may be provided with left and right speakers for playing audio to a user. Control circuitry in the electronic device may play audio through the speakers in an unreversed configuration in which left channel audio is played through a first of the speakers that is adjacent to a left ear of the user and right channel audio is played through a second of the speakers that is adjacent to a right ear of the user or a reversed configuration in which these channel assignments are reversed. The headphones may have ear cups that house the speakers. Capacitive touch sensors, force sensors, and other sensors on the ear cups may measure ear shapes and finger grip positions on the ear cups to determine whether to operate in the unreversed or reversed configuration. Sensors may gather gestures and other user touch input.

Abstract: A piezoelectric thin film resonator includes: an acoustic reflection layer including an air gap or an acoustic mirror; lower and upper electrodes facing each other in a stacking direction, at least a part of each of the lower and upper electrodes being located on or above the acoustic reflection layer; a piezoelectric film sandwiched between the lower and upper electrodes and including lower and upper piezoelectric films, at least a part of an end face of the piezoelectric film in a film thickness direction being located between outer outlines of the resonance region and the acoustic reflection layer in at least a part of a region surrounding a resonance region; and an insertion film inserted between the lower and upper piezoelectric films, located in at least a part of an outer peripheral region within the resonance region, and not located in a center region of the resonance region.