Abstract: In an embodiment, a thermal stress resistant resonator is disclosed. The thermal stress resistant resonator may include or comprise a piezoelectric member having one or more non-linear piezoelectric support members extending there from.

Abstract: A method of manufacturing a piezoelectric device includes the steps of bonding a first substrate to a second substrate having a toughness greater than that of the first substrate, forming a first though-hole through the first substrate from the side opposite to the side on which the second substrate is bonded, and forming a second through-hole through the second substrate at a location corresponding to the first through-hole by a formation method different from that used to form the first through-hole from the side opposite to the side on which the first substrate is bonded.

Abstract: A piezoelectric device includes first and second piezoelectric resonators each including a piezoelectric thin film, an upper electrode provided on one main surface of the piezoelectric thin film, and a lower electrode provided on another main surface of the piezoelectric thin film. In the piezoelectric resonators, portions in which the upper and lower electrodes are superposed on each other with the piezoelectric thin film therebetween define piezoelectric vibrating portions that are acoustically isolated from a substrate. The first and second piezoelectric resonators are connected in series or parallel between an input terminal and an output terminal such that polarization directions of corresponding portions of the piezoelectric thin film are opposite to each other when seen from the input terminal. The first piezoelectric resonator and the second piezoelectric resonator are arranged to have different resonant frequencies of a transverse vibration mode.

Abstract: An autonomous, self-powered device includes a radioisotope-powered current impulse generator including a spring assembly comprising a cantilever, and a piezoelectric-surface acoustic wave (P-SAW) structure connected in parallel to the current impulse generator. Positive charges are accumulated on an electrically isolated 63Ni thin film due to the continuous emission of ?-particles (electrons), which are collected on the cantilever. The accumulated charge eventually pulls the cantilever into the radioisotope thin-film until electrical discharge occurs. The electrical discharge generates a transient magnetic and electrical field that can excite the RF modes of a cavity in which the electrical discharge occurs. A piezoelectric-SAW resonator is connected to the discharge assembly to control the RF frequency output.

Abstract: A piezoelectric resonator includes a resonator substrate having a resonating body with a thickness that is associated with a resonant frequency, a conductor disposed on the resonating body and having a body electrode, a base having a groove aligned with the body electrode and defined by a groove-defining wall, a base electrode disposed on the groove-defining wall and cooperating with the body electrode and the base to form a capacitor load, and a cap disposed on the resonator substrate in a manner that the resonator substrate is sandwiched between the cap and the base.

Abstract: An acoustic wave device includes: a first piezoelectric thin film resonator including a first lower electrode, a first upper electrode and a first piezoelectric film sandwiched between the first lower and upper electrodes; a decoupler film provided on the first upper electrode; and a second piezoelectric thin film resonator provided on the decoupler film and including a second lower electrode, a second upper electrode and a second piezoelectric film sandwiched between the second lower and upper electrodes, wherein the first piezoelectric film and the second piezoelectric film comprise aluminum nitride and include an element increasing a piezoelectric constant of the aluminum nitride.

Abstract: The invention relates to a resonator of the harmonic bulk acoustic resonator HBAR type, comprising a piezoelectric transducer (6) clamped between two electrodes (4, 8) with a strong electroacoustic coupling, cut according to a first cutting angle ?1, and an acoustic substrate (10) with a working frequency acoustic quality coefficient at least equal to 5·1012, cut according to a second cutting angle ?2 with at least one shearing vibration mode. The transducer and the substrate are arranged in such a way that the polarization direction of the shearing mode of the transducer and the polarization direction of the shearing of the substrate are aligned, and the second cutting angle ?2 is such that the temperature coefficient of the frequency of the first order CTFB1 corresponding to the shearing mode and to the second cutting angle ?2 is zero with inversion of the sign thereof on either side of, or equal to, a bias.

Abstract: A crystal resonator comprises a first vibrating region provided on a crystal wafer, a second vibrating region provided on the crystal wafer, the second vibrating region having a different thickness and positive/negative orientation of the X-axis from those of the first vibrating region, and excitation electrodes which are provided respectively on the first vibrating region and the second vibrating region for causing the vibrating regions to vibrate independently. Frequencies that change by different amounts from each other relative to a temperature change can be retrieved from one vibrating region and the other vibrating region. Thus, based on an oscillating frequency of the vibrating region in which a clear frequency change occurs relative to the temperature, the oscillating frequency of the other vibrating region can be controlled. Thereby, increases in the complexity of the crystal oscillator can be suppressed.

Abstract: Piezoelectric vibrating devices are disclosed that lack base through-holes and that can be manufactured on a wafer scale. Also disclosed are methods for making same. An exemplary piezoelectric device has a package base having first and second opposing main surfaces. On the second (outer) first main surface is formed a pair of external electrodes. The first (inner) main surface defines a first recess and a peripheral first bonding surface. A pair of connecting electrodes are provided for connecting to the respective external electrodes via respective edge surfaces of the package base that extend between the first and second main surfaces. A piezoelectric vibrating piece is mounted in and contained within the package base. The vibrating piece includes a pair of excitation electrodes electrically connected to respective connecting electrodes. A package lid comprises first and second main surfaces, of which the second (inner) main surface defines a second recess that is larger than the first recess.

Abstract: The various embodiments of the present disclosure relate generally bulk-acoustic-wave resonators. An exemplary embodiment of the present invention provides a bulk-acoustic-wave resonator comprising an acoustic reflector, a substantially c-axis oriented hexagonal crystal structure, and a plurality of electrodes. The crystal structure is solidly-mounted to the acoustic reflector. The bulk-wave resonator resonates in at least two non-harmonically-related operational modes.

Abstract: The invention relates to a resonator of the high bulk acoustic resonator HBAR type, for operating at a pre-determined working frequency, comprising: a piezoelectric transducer (6), an acoustic substrate (10), a counter-electrode (8) formed by a metal layer adhering to a first face of the transducer (6) and a face of the acoustic substrate (10), and an electrode (4) arranged on a second face of the transducer (6) facing away from the first face of the transducer (6) and the substrate (10).

Abstract: In a representative embodiment, a bulk acoustic wave (BAW) resonator, comprises: a first electrode disposed over a substrate; a first piezoelectric layer disposed over the first electrode, the first piezoelectric layer having a first c-axis oriented along a first direction; a second electrode disposed over the first piezoelectric layer; and a second piezoelectric layer disposed over the first electrode and adjacent to the first piezoelectric layer, wherein the second piezoelectric layer has a second c-axis oriented in a second direction that is substantially antiparallel to the first direction.

Abstract: AT-cut quartz-crystal vibrating pieces and corresponding quartz-crystal devices are disclosed each having a vibrating portion surrounded by a frame portion across a through-slot configured to provide a wide vibrating portion. An exemplary vibrating piece has a quartz-crystal vibrating portion that vibrates when electrically energized, a frame portion surrounding the vibrating portion, and a through-slot defined between the vibrating portion and the frame portion. The through-slot includes a first through-slot extending in the X-axis direction along +Z?-edge of the vibrating portion, and a second through-slot extending in the X-axis direction along the ?Z?-edge of the vibrating portion. The first through-slot has a different width than the second through-slot.

Abstract: A piezoelectric thin film resonator includes: a substrate; a piezoelectric film located on the substrate; a lower electrode and an upper electrode located to sandwich the piezoelectric film; a load film formed from patterns in a resonance region in which the lower electrode and the upper electrode face each other across the piezoelectric film, wherein the patterns are formed so as to surround a center of the resonance region and intersect with a pathway extending from the center to an outer periphery of the resonance region.

Abstract: A piezoelectric resonator element includes a piezoelectric substrate formed of an AT-cut quartz crystal substrate in which the thickness direction thereof is a direction parallel to the Y? axis; and excitation electrodes disposed so as to face vibrating regions on both front and rear principal surfaces of the piezoelectric substrate. The piezoelectric substrate includes a rectangular excitation portion in which sides parallel to the X axis are long sides thereof, and sides parallel to the Z? axis are short sides thereof; and a peripheral portion having a smaller thickness than the excitation portion and formed around the excitation portion. Each of side surfaces of the excitation portion extending in a direction parallel to the X axis is present in one plane, and each of side surfaces of the excitation portion extending in a direction parallel to the Z? axis has a step.

Abstract: A crystal resonator includes a mesa-type crystal element, a pair of excitation electrodes, and a deformed portion. The mesa-type crystal element has a principal surface portion and a peripheral edge portion. The peripheral edge portion surrounds the principal surface portion and has a smaller thickness than the principal surface portion. The pair of excitation electrodes are formed at the principal surface portion on one surface side and the principal surface portion on an other surface side of the crystal element, respectively. The deformed portion is configured to reduce a vibration different from a main vibration and confine energy to the principal surface portion.

Abstract: A method of manufacturing a ladder filter including first and second resonators includes: forming a piezoelectric film on an entire surface of a substrate that has respective lower electrodes of the first and second resonator formed thereon, an conductive film on the piezoelectric film, and a second film on the conductive film; forming a pattern of the second film in a prescribed region in the second area; forming a first film on an entire surface of the substrate; etching the first film, forming a pattern of the first film, the second film and the conductive film in the second area, and forming a pattern of the first film and the conductive film in the first area, to form respective upper electrodes from the conductor film; and thereafter, etching the piezoelectric film to form respective patterns of the piezoelectric film in the first and second areas, respectively.

Abstract: A resonance coupler includes transmission-side resonant wiring provided on a transmission substrate and connected to a transmission ground between a connection point of first transmission wiring to the transmission-side resonant wiring and a connection point of second transmission wiring to the transmission-side resonant wiring, and reception-side resonant wiring provided on a reception substrate and connected to a reception ground between a connection point of first reception wiring to the reception-side resonant wiring and a connection point of second reception wiring to reception-side resonant wiring. When viewed in a direction perpendicular to a main surface of the transmission substrate, the transmission substrate and the reception substrate are provided facing each other so that the transmission-side resonant wiring and the reception-side resonant wiring are symmetric about a point and have matching contours.

Abstract: A method of producing an acoustic wave device includes: forming an interdigital electrode on a piezoelectric substrate; forming a barrier film so as to cover the interdigital electrode; forming a medium on the barrier film; measuring a frequency characteristic of an acoustic wave excited by the interdigital electrode; and forming, in an excitation region, an adjustment region having a thickness different from other portions by patterning the barrier film or further providing an adjustment film. When forming the adjustment region, an area T of the adjusting area is adjusted in accordance with the measured frequency characteristic.

Abstract: An electromagnetic resonance coupler including: a transmitting resonator provided on a transmission substrate and having an open loop shape having an opening, first wiring provided on the transmission substrate and connected to a first connection point on the transmitting resonator, a receiving resonator provided on the reception substrate, second wiring provided on the reception substrate and connected to a second connection point on the receiving resonator, and third wiring provided on the reception substrate and connected to a third connection point on the receiving resonator. When viewed in a direction perpendicular to a main surface of the transmission substrate, the transmission substrate and the reception substrate are provided facing each other so that the transmitting resonator and the receiving resonator are symmetric about a point and have matching contours.

Abstract: A variety of micromachined structures are disclosed for use in DC-tunable ultrasound transducers.

Abstract: A mesa-shaped piezoelectric resonator element including a resonator section having a thicker thickness than a peripheral section on the board surface of a piezoelectric substrate formed in a rectangular shape, wherein, when the length of the long side of the piezoelectric substrate is x and the board thickness of the resonator section is t, etching depth y of a level-difference section is set to fulfill a relationship in the following equation, based on the board thickness t. y = - 1.

Abstract: A method of manufacturing a boundary acoustic wave device includes the steps of forming an electrode on a first medium layer, forming a second medium layer so as to cover the electrode on the first medium layer, and forming a sound absorbing layer on an external surface of the second medium layer. The sound absorbing layer has an acoustic velocity of transverse waves that is lower than an acoustic velocity of transverse waves of the second medium layer.

Abstract: A periodic signal generator is configured to generate high frequency signals characterized by relatively low temperature coefficients of frequency (TCF). This generator may include an oscillator containing a pair of equivalent MEMs resonators therein, which are configured to support bulk acoustic wave and surface wave modes of operation at different resonance frequencies. Each resonator includes a stack of layers including a semiconductor resonator body (e.g., Si-body), a piezoelectric layer (e.g., AIN layer) on the resonator body and interdigitated drive and sense electrodes on the piezoelectric layer. The oscillator is configured to support the generation of first and second periodic signals having unequal first and second frequencies (f1, f2) from first and second resonators within the pair. These first and second periodic signals are characterized by respective first and second temperature coefficients of frequency (TCf1, TCf2), which may differ by at least about 10 ppm/° C.

Abstract: A piezoelectric thin film resonator of the present has a substrate 1, an intermediate layer 7 disposed on the substrate 1 and is formed of an insulator, a lower electrode 3 disposed on the intermediate layer 7, a piezoelectric film 4 disposed on the lower electrode 3, and an upper electrode 5 disposed on a position facing the lower electrode 3 with the piezoelectric film 4 interposed therebetween, in which, in a resonant region 8 where the lower electrode 3 and the upper electrode 5 face each other, a space 6 is formed in the substrate 1 and the intermediate layer 7 or between the lower electrode 3 and the intermediate layer 7 and the region of the space 6 is included in the resonant region 8. With the structure, the dissipation of the vibrational energy to the substrate from the resonance portion can be suppressed, thereby improving the quality factor.

Abstract: In one general aspect, various embodiments are directed to an ultrasonic surgical instrument that comprises a transducer configured to produce a standing wave of vibrations along a longitudinal axis having a node and an anti-node at a predetermined frequency. In various embodiments, an ultrasonic blade extends along the longitudinal axis and is coupled to the transducer. In various embodiments, the ultrasonic blade includes a body having a proximal end and a distal end, wherein the distal end is movable relative to the longitudinal axis by the vibrations produced by the transducer. In one general aspect, various embodiments are directed to a method of assembling the transducer for the ultrasonic surgical instrument. In various embodiments, the method comprises selecting piezoelectric elements and arranging the piezoelectric elements relative to the node to minimize the difference in magnitude between the currents drawn by the piezoelectric elements.

Abstract: A vibrating element includes: an element plate that has a vibrating portion that performs thickness-shear vibration, a peripheral portion that is integrally formed with the vibrating portion, and a protruding portion that is provided at the peripheral portion; and an excitation electrode that is provided at the vibrating portion. When a side length of the vibrating portion is Mx, when a side length of the excitation electrode is Ex, and when a wavelength of flexure vibrations of the element plate is ?, the relationship of (Mx?Ex)/2=?/2, and Mx/2={(A/2)+(¼)}? (where, A is a positive integer) is satisfied, and when a length of the protruding portion is Dx, and when a distance between the vibrating portion and the protruding portion is Sx, the relationship of Dx=?/2)×m, and (?/2)×n?0.1??Sx?(?/2)×n+0.1? (where m and n are positive integers) is satisfied.

Abstract: A component (1) is proposed wherein the suspension of the component (1) is effected in a stress-reduced manner. The component (1) can rest on a membrane (4) or be held by a spring element (2). The membrane (4) or the spring element (2) is situated above a depression (6) or an opening (7) partially spanned by the membrane (4). Preferably, the membrane (4) has a modulus of elasticity that is less than or equal to the modulus of elasticity of the component (1) or of the substrate (3). The component (1) can be covered with metal electrodes (10) wholly or partially over the area on two sides.

Abstract: In one aspect of the invention, an acoustic wave device includes a substrate, and at least one acoustic wave resonator having a bottom electrode adjacent to the substrate, a top electrode, a piezoelectric layer sandwiched between the bottom and top electrodes, a passivation layer formed on the top electrode, and a mass load layer sandwiched between the substrate and the bottom electrode, or between the bottom electrode and the piezoelectric layer.

Abstract: A stacked bulk acoustic resonator includes a first piezoelectric layer stacked on a first electrode, a second electrode stacked on the first piezoelectric layer; a second piezoelectric layer stacked on the second electrode, and a third electrode stacked on the second piezoelectric layer. The stacked bulk acoustic resonator further includes an inner raised region formed in an inner portion on a surface of at least one of the first, second and third electrodes, and an outer raised region formed along an outer perimeter on the surface of the at least one of the first, second or third electrodes. The outer raised region surrounds the inner raised region and defines a gap between the inner raised region and the outer raised region.

Abstract: In an embodiment, a piezoelectric resonator configured for parametric amplification is disclosed. The piezoelectric resonator may include or comprise a piezoelectric member, and first and second resonator electrodes associated with the piezoelectric member and positioned to enable a first electric field to be generated in a first direction. The piezoelectric resonator may also include or comprise a parametric drive electrode associated with the piezoelectric member and positioned to enable a second electric field to be generated in a second direction.

Abstract: The present invention is directed to monolithic integrated circuits incorporating an oscillator element that is particularly suited for use in timing applications. The oscillator element includes a resonator element having a piezoelectric material disposed between a pair of electrodes. The oscillator element also includes an acoustic confinement structure that may be disposed on either side of the resonator element. The acoustic confinement element includes alternating sets of low and high acoustic impedance materials. A temperature compensation layer may be disposed between the piezoelectric material and at least one of the electrodes. The oscillator element is monolithically integrated with an integrated circuit element through an interconnection. The oscillator element and the integrated circuit element may be fabricated sequentially or concurrently.

Abstract: An electromagnetic resonance coupler includes a transmission resonator provided on the transmission substrate and having a shape obtained by opening a loop shape including an inwardly recessed portion in part to make a transmission resonator slit, transmission wiring connected to the transmission resonator, a reception substrate, a reception resonator provided on the reception substrate and having the same size and shape as the transmission resonator, and reception wiring connected to the reception resonator. The transmission and reception resonators are symmetric with respect to a point and face each other so that their contours match. In the transmission resonator, at least part of wiring constituting the recessed portion is close to wiring other than the at least part of wiring at a distance less than or equal to four times the wiring width of the transmission resonator.

Abstract: A piezoelectric resonator includes: a piezoelectric plate having a vibrating portion surrounded by a peripheral portion; and an excitation electrode on the piezoelectric plate, wherein long sides of the vibrating portion and excitation electrode are parallel to a piezoelectric plate long side. Assuming a piezoelectric plate long side length X, a vibrating portion thickness t, a vibrating portion long side length Mx, an excitation electrode long side length Ex, and a piezoelectric plate flexure vibration wavelength ?, ?/2=(1.332/f)?0.0024 (piezoelectric resonator resonance frequency f), (Mx?Ex)/2=?/2, Mx/2={(A/2)+(1/4)}? (where, A is a positive integer), and X?20t. A protruding portion is disposed on a vibrating portion extension line and parallel to a vibrating portion short side. Assuming a protruding portion length Dx, Dx=(?/2)×m (where, m is a positive integer). Assuming a distance Sx between the vibrating and protruding portions, Sx=(?/2)×n±0.1? (where, n is a positive integer).

Abstract: A tunable acoustic resonator device has a piezoelectric medium as a first thin film layer and a tunable crystal medium as a second thin film layer. The tunable crystal medium has a first acoustic behavior over an operating temperature range under a condition of relatively low applied stress and a second acoustic behavior under a condition of relatively high applied stress. The acoustic behaviors are substantially different and, consequently, the different levels of applied stress are used to tune the acoustic resonator device. Compared with the tunable resonator device consisting of only tunable crystal medium, a device having both the piezoelectric and tunable crystal medium has advantages such as larger inherent bandwidth and less nonlinearity with AC signals. The device also requires a smaller applied stress (i.e. bias voltage) to achieve the required frequency tuning.

Abstract: Microelectromechanical resonators include a resonator body having a first piezoelectric layer on a upper surface thereof, which is configured to support actuation and sensing through a transverse piezoelectric effect (e31), and a second piezoelectric layer on at least a portion of a first sidewall thereof, which is configured to support actuation and sensing through a longitudinal piezoelectric effect (e33), where e33 is greater than e31. These resonators may further include a first bottom electrode extending between the first piezoelectric layer and the upper surface of the resonator body and a second bottom electrode extending between the second piezoelectric layer and the first sidewall of the resonator body. These first and second bottom electrodes may be contiguous as a single bottom electrode and the first and second piezoelectric layers may be contiguous as a single piezoelectric layer.

Abstract: Mechanical resonating structures and related methods are described. The mechanical resonating structures may provide improved efficiency over conventional resonating structures. Some of the structures have lengths and widths and are designed to vibrate in a direction approximately parallel to either the length or width. They may have boundaries bounding the length and width dimensions, which may substantially align with nodes or anti-nodes of vibration.

Abstract: A bulk acoustic wave resonator structure that isolates the core resonator from both environmental effects and aging effects. The structure has a piezoelectric layer at least partially disposed between two electrodes. The structure is protected against contamination, package leaks, and changes to the piezoelectric material due to external effects while still providing inertial resistance. The structure has one or more protective elements that limit aging effects to at or below a specified threshold. The resonator behavior is stabilized across the entire bandwidth of the resonance, not just at the series resonance. Examples of protective elements include a collar of material around the core resonator so that perimeter and edge-related environmental and aging phenomena are kept away from the core resonator, a Bragg reflector formed above or below the piezoelectric layer and a cap formed over the piezoelectric layer.

Abstract: A transverse acoustic wave resonator includes a base, a resonator component, a number of driving electrodes fixed to the base and a number of fixing portions connecting the base and the resonator component. The resonator component is suspended above a top surface of the base and is perpendicular to the base. The driving electrodes are coupling to side surfaces of the resonator component. The resonator component is formed in a shape of an essential regular polygon. The driving electrodes and the resonator component jointly form an electromechanical coupling system for converting capacitance into electrostatic force. Besides, a capacitive-type transverse extension acoustic wave silicon oscillator includes the transverse acoustic wave resonator and a method of fabricating the transverse acoustic wave resonator are also disclosed.

Abstract: A dual mode vibrator is disclosed. There are available two vibrating units to enable obtainment of a variety of vibrations. Each lateral portion of the first and second vibrating units respectively supported by the first and second elastic members is supported by the first and second support bars secured at the housing for rotatable installation. Therefore, although the first and second vibrating units may rotate about the first and second support bars, the first and second vibrating units are not allowed to deviated or disengaged from the first and second support bars, whereby the plastic deformation of the first and second elastic members is prevented, and the first and second vibrating units can be positioned at predetermined positions at all times to enhance reliability of product.

Abstract: A piezoelectric thin-film resonator includes a substrate, a lower electrode provided on the substrate, a piezoelectric film provided on the substrate and the lower electrode, an upper electrode provided on the piezoelectric film, and an additional pattern, a cavity being formed between the lower electrode and the substrate in a resonance portion in which the lower electrode and the upper electrode face each other through the piezoelectric film, the additional pattern being provided in a position that is on the lower electrode and includes an interface between the resonance portion and a non-resonance portion.

Abstract: An acoustic resonator device includes a composite first electrode on a substrate, a piezoelectric layer on the composite electrode, and a second electrode on the piezoelectric layer. The first electrode includes a buried temperature compensating layer having a positive temperature coefficient. The piezoelectric layer has a negative temperature coefficient, and thus the positive temperature coefficient of the temperature compensating layer offsets at least a portion of the negative temperature coefficient of the piezoelectric layer.

Abstract: Piezoelectric vibrating pieces are disclosed having selectively roughened surfaces. An exemplary piece is made of a piezoelectric material configured as a piezoelectric substrate. The piece also includes at least one excitation electrode and at least one extraction electrode. The substrate has opposing main surfaces initially having low surface roughness. At least one main surface is formed in a mesa or reverse mesa manner, wherein the central region has a different thickness than the peripheral region. The central region has relatively low surface roughness (irregular unevenness), while the peripheral region has relatively high surface roughness. The excitation electrode is formed on the central region (mesa or reverse mesa) while the extraction electrode (connected to the excitation electrode) is formed on the peripheral region.

Abstract: A piezoceramic transducer (PZT transducer) and a method for manufacturing the same are provided. The PZT transducer includes a piezoceramic substrate and an electrode unit. The piezoceramic substrate has a first surface and a second surface opposite the first surface, and has a mechanical quality factor (Qm) greater than 1400. The electrode unit has a first electrode and a second electrode. The first electrode is disposed on the first surface and has a first diameter. The second electrode covers the second surface and extends to cover a part of the surface at a periphery of the first surface, and the part of the second electrode covering the second surface has a second diameter. The ratio of the first diameter to the second diameter is 0.498 to 0.502. The PZT transducer has a large mist amount and a long service life.

Abstract: A method of manufacturing a boundary acoustic wave device includes the steps of forming an electrode on a first medium layer, forming a second medium layer so as to cover the electrode on the first medium layer, and forming a sound absorbing layer on an external surface of the second medium layer. The sound absorbing layer has an acoustic velocity of transverse waves that is lower than an acoustic velocity of transverse waves of the second medium layer.

Abstract: A crystal resonator comprises a first vibrating region provided on a crystal wafer, a second vibrating region provided on the crystal wafer, the second vibrating region having a different thickness and positive/negative orientation of the X-axis from those of the first vibrating region, and excitation electrodes which are provided respectively on the first vibrating region and the second vibrating region for causing the vibrating regions to vibrate independently. Frequencies that change by different amounts from each other relative to a temperature change can be retrieved from one vibrating region and the other vibrating region. Thus, based on an oscillating frequency of the vibrating region in which a clear frequency change occurs relative to the temperature, the oscillating frequency of the other vibrating region can be controlled. Thereby, increases in the complexity of the crystal oscillator can be suppressed.

Abstract: A bulk acoustic wave (BAW) resonator, comprises: a first electrode formed on a substrate; a piezoelectric layer formed on the first electrode; a second electrode formed on the first piezoelectric layer; a non-piezoelectric layer formed on the first electrode and adjacent to the piezoelectric layer; and a bridge formed between the non-piezoelectric layer and the first or second electrode.

Abstract: An acoustic wave device includes a main resonator and a sub resonator each having a substrate, a lower electrode provided on the substrate, a piezoelectric film provided on the lower electrode, and an upper electrode provided on an upper side of the piezoelectric film. The sub resonator has a mass addition film on the upper electrode in a resonance area in which the upper electrode and the lower electrode face each other. At least one of the main resonator and the sub resonator is provided with a frequency control film on an upper side of the resonance area, and the frequency control film has a weight per unit area smaller than a weight of the mass addition film per unit area.

Abstract: In a representative embodiment, a bulk acoustic wave (BAW) resonator structure comprises: a first electrode disposed over a substrate; a first piezoelectric layer disposed over the first electrode; a second electrode disposed over the first piezoelectric layer, wherein c-axis orientations of crystals of the first piezoelectric layer are substantially aligned with one another; a second piezoelectric layer disposed over the second electrode; a non-piezoelectric layer; and a third electrode disposed over the second piezoelectric layer.

Abstract: The present invention is a piezoelectric crystal oscillator using parametric amplification to enhance the Q. Parametric amplification is accomplished by driving the same region of the crystal as used for the oscillator with an overtone of the crystal resonator.