Abstract: A single-crystal bulk acoustic wave resonators with better performance and better manufacturability and a process for fabricating the same are described. A low-acoustic-loss layer of one or more single-crystal and/or poly-crystal piezoelectric materials is epitaxially grown and/or physically deposited on a surrogate substrate, followed with the formation of a bottom electrode and then a support structure on a first side of the piezoelectric layer. The surrogate substrate is subsequently removed to expose a second side of the piezoelectric layer that is opposite to the first side. A top electrode is then formed on the second side of the piezoelectric layer, followed by further processes to complete the BAW resonator and filter fabrication using standard wafer processing steps. In some embodiments, the support structure has a cavity or an acoustic mirror adjacent the first electrode layer to minimize leakage of acoustic wave energy.

Abstract: A multiplexer includes a band pass filter configured to pass a signal in a predetermined frequency band between a first terminal and a common terminal connected to an antenna, and a band elimination filter configured to attenuate a signal in the predetermined frequency band between a second terminal and the common terminal and includes resonators connected in series with a line between the second terminal and the common terminal. The resonators include a first resonator having a lowest resonant frequency and a second resonator disposed on a side of the common terminal from the first resonator.

Abstract: A microelectromechanical resonator device is provided having two-dimensional resonant rods. The resonator device has a piezoelectric layer formed with a plurality of alternating rods and trenches. A bottom electrode is in contact with a bottom surface of the piezoelectric layer. A top electrode metal grating of conductive strips is aligned in contact with corresponding rods of the piezoelectric layer.

Abstract: An air-gap type film bulk acoustic resonator (FBAR) is provided. The air-gap type FBAR includes a substrate which comprises an air gap portion having a substrate cavity formed in a top surface, a lower electrode formed on the substrate, a piezoelectric layer which is formed on the lower electrode and has one side forming an edge portion in the vicinity of a virtual edge according to vertical projection of the air gap portion, an upper electrode formed on the piezoelectric layer, a first electrode frame which comprises an open ring structure in plane, the open ring structure surrounding a part of a periphery of the piezoelectric layer on the lower electrode, and a second electrode frame positioned on the upper electrode and adjacent to an open portion of the open ring structure.

Abstract: An acoustic filter circuit for noise suppression outside resonance frequency is provided. The acoustic filter circuit includes a first filter branch and a second filter branch. The first filter branch and the second filter branch are both configured to resonate at a resonance frequency to pass a radio frequency (RF) signal, but in opposite phases. The acoustic filter circuit also includes a shunt circuit coupled between the first filter branch and the second filter branch. As discussed in various embodiments in the detailed description, the shunt circuit can be configured to protect the RF signal located inside the resonance frequency and suppress noises located outside the resonance frequency. As such, the acoustic filter circuit can provide improved noise rejection and reduce insertion loss.

Abstract: A BAW resonator (BAWR) with improved power durability and improved heat resistance is provided. The resonator comprises a layer stack with a piezoelectric material (PM) between a bottom electrode (ELI) and a top electrode (EL2) and a shunt path parallel (PCPP) to the layer stack provided to enable an RF signal to bypass the layer stack, e.g. to ground (GND). The shunt path (PCPP) has a temperature dependent conductance with a negative temperature coefficient, NTC, of resistance. When the temperature of the device rises due to high power operation, currents that would otherwise permanently damage the device are shunted to ground or another dedicated terminal by the temperature dependent shunt path. Upon cooling down normal operation is resumed.

Abstract: A front end module (FEM) for a 5.6/6.6 GHz Wi-Fi acoustic wave resonator RF filter circuit. The device can include a power amplifier (PA), a 5.6/6.6 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 5.6/6.6 GHZ resonator may be configured between the diversity switch and the LNA. In a specific example, this device integrates a 5.6/6.6 GHz PA, a 5.6/6.6 GHZ bulk acoustic wave (BAW) RF filter, a single pole two throw (SP2T) switch, and a bypassable LNA into a single device.

Abstract: A resonator includes a silicon substrate, a bottom electrode stacked on a portion of the silicon substrate, a piezoelectric layer covering the bottom electrode and another portion of the silicon substrate, a top electrode stacked on the piezoelectric layer, and a Bragg reflecting ring. The Bragg reflecting ring is formed on a side of the piezoelectric layer connected to the top electrode and surrounds the top electrode. The Bragg reflecting ring includes a Bragg high-resistivity layer and a Bragg low-resistivity layer alternately arranged along the radial direction of the Bragg reflecting ring. An acoustic impedance of the Bragg high-resistivity layer is greater than an acoustic impedance of the Bragg low-resistivity layer. The Bragg reflecting ring forms reflection surfaces to reflect the laterally propagating clutter waves, thereby suppressing the parasitic mode in the working frequency band, improving the frequency response curve of the resonator and the overall performance of the resonator.

Abstract: A TF-SAW resonator with improved quality factor is provided. The resonator has its piezoelectric material in the form of a thin film and an electrode structure arranged on the piezoelectric layer. Pitch (P) and metallization ratio (n) are chosen to maximize the quality factor (Q).

Abstract: Techniques for improving Bulk Acoustic Wave (BAW) resonator structures are disclosed, including filters, oscillators and systems that may include such devices. First and second layers of piezoelectric material may be acoustically coupled with one another to have a piezoelectrically excitable resonance mode. The first layer of piezoelectric material may have a first piezoelectric axis orientation, and the second layer of piezoelectric material may have a second piezoelectric axis orientation that opposes the first piezoelectric axis orientation of the first layer of piezoelectric material. A top acoustic reflector including a first pair of top metal electrode layers may be electrically and acoustically coupled with the first layer of piezoelectric material to excite the piezoelectrically excitable main resonance mode at a resonant frequency.

Abstract: The invention provides a film bulk acoustic resonator including a layered structure composed of a top electrode, a piezoelectric layer and a bottom electrode, and a substrate; a reflective interface is arranged between the bottom electrode and the substrate; and by defining the shape of all or part of the layered structure, the purpose of suppressing the lateral mode can be achieved, and without adding new process, the manufacturing cost of the device can be controlled, and the benefit of product development can be maximized.

Abstract: A resonator includes a substrate, an acoustic Bragg mirror disposed above the substrate, and a bottom metal layer disposed above the acoustic Bragg mirror. The resonator also includes a piezoelectric plate disposed above the bottom metal layer. The resonator further includes a top metal layer disposed above the piezoelectric plate. The top metal layer comprises multiple fingers within a single plane and the width of each of the fingers is between 75%-125% of a thickness of the piezoelectric plate.

Abstract: A bulk acoustic wave resonator includes: a substrate; a membrane layer forming a cavity together with the substrate; a lower electrode disposed on the membrane layer; a piezoelectric layer disposed on a flat surface of the lower electrode; and an upper electrode covering a portion of the piezoelectric layer and exposing a side of the piezoelectric layer to air, wherein the piezoelectric layer includes a step portion extended from the side of the piezoelectric layer and disposed on the flat surface of the lower electrode.

Abstract: An acoustic wave device includes: a piezoelectric substrate; electrodes sandwiching the piezoelectric substrate and exciting a thickness shear vibration in the piezoelectric substrate; and an edge region that is a region surrounding a center region of a resonance region, wherein a first region of the edge region is located on both sides of the center region in a first direction substantially parallel to a displacement direction of a thickness shear vibration, a second region of the edge region is located on both sides of the center region in a second direction substantially perpendicular to the first direction, a width of the second region is different from a width of the first region, and acoustic velocities of acoustic waves in the piezoelectric substrate in the first and second regions are less than that in the piezoelectric substrate in the center region.

Abstract: An acoustic resonator comprises a substrate, a resonant portion disposed on the substrate and in which a first electrode, a piezoelectric layer, and a second electrode are stacked, a protective layer disposed on an upper portion of the resonant portion, and a hydrophobic layer formed on the protective layer, and the protective layer comprises a first protective layer stacked on the second electrode and a second protective layer stacked on the first protective layer, wherein a density of the second protective layer is higher than a density of the first protective layer.

Abstract: An example integrated circuit package includes an acoustic wave resonator, the acoustic wave resonator including a Fresnel surface. In some examples, the Fresnel surface includes a plurality of recessed features and/or protruding features at different locations on the Fresnel surface, each of the plurality of features to confine main mode acoustic energy from a respective portion of the Fresnel surface in a central portion of the acoustic wave resonator.

Abstract: A device employing the generation and enhancement of surface acoustic waves on a highly doped p-type III-V semiconductor substrate (e.g., GaAs, GaSb, InAs, or InGaAs). The device includes two SiO2/ZnO islands, each including a SiO2 buffer layer deposited on the doped p-type III-V semiconductor substrate and a ZnO layer deposited on the SiO2 buffer layer. An input interdigital transducers (IDT) and an output IDT are each patterned on one of the SiO2/ZnO islands. The IDTs generates surface acoustic waves along an exposed surface of the highly doped p-type III-V semiconductor substrate. The surface acoustic waves improve the photoelectric and photovoltaic properties of the device. The device is manufactured using a disclosed technique for propagating strong surface acoustic waves on weak piezoelectric materials. Also disclosed is a photodetector developed using that technique.

Abstract: Aspects of this disclosure relate to acoustic wave filters that include a Lamb wave resonator and a second acoustic wave resonator that is a different type of acoustic wave resonator than the Lamb wave resonator. The different type of resonator can be a film bulk acoustic wave resonator for example. Some embodiments of this disclosure relate to an acoustic wave filter that includes the Lamb wave resonator and the second acoustic wave resonator. Some embodiments of this disclosure related to different respective acoustic wave filters including the Lamb wave resonator and the second acoustic wave resonator, in which the Lamb wave resonator and the second acoustic wave resonator are implemented on a common substrate.

Abstract: A resonator that includes a substrate with a cavity that extends in a principal surface thereof and a vibrating resonator above the principal surface of the substrate and including bottom and top electrodes with a piezoelectric layer disposed therebetween. Moreover, a silicon dioxide layer is provided above the substrate and below the vibrating resonator to cover the cavity of the substrate, and a silicon layer is provided between the silicon dioxide layer and the vibrating resonator. The bottom electrode, the top electrode and the piezoelectric layer of the vibrating resonator each have a thickness configured to accommodate substantially a half wavelength ?/2 of the resonator, and the silicon layer has a thickness that accommodates substantially multiple of the half wavelength ?/2 of the resonator.

Abstract: A resonator circuit device. This device can include a piezoelectric layer having a front-side electrode and a back-side electrode spatially configured on opposite sides of the piezoelectric layer. Each electrode has a connection region and a resonator region. Each electrode also includes a partial mass-loaded structure configured within a vicinity of its connection region. The front-side electrode and the back-side electrode are spatially configured in an anti-symmetrical manner with the resonator regions of both electrodes at least partially overlapping and the first and second connection regions on opposing sides. This configuration provides a symmetric acoustic impedance profile for improved Q factor and can reduce the issues of misalignment or unbalanced boundary conditions associated with conventional single mass-loaded perimeter configurations.

Abstract: An acoustic wave filter device includes resonance portions, first and second metal pads. The resonance portions each includes a lower electrode disposed on a substrate, a piezoelectric layer disposed on at least a portion of the lower electrode, and an upper electrode disposed on at least a portion of the piezoelectric layer. The first metal pads are connected to one of the upper electrode and the lower electrode of a corresponding resonance portion among the resonance portions. The second metal pads are disposed outwardly of an active region and connected to the other one of the upper electrode and the lower electrode of adjacent resonant portions among the resonance portions. A ring portion is disposed outwardly of the active region in which the lower electrode, the piezoelectric layer, and the upper electrode overlap is disposed only on a portion of any one of the first and second metal pads.

Abstract: Bulk acoustic wave resonators having a phononic crystal acoustic mirror are disclosed. An example integrated circuit package includes a bulk acoustic wave (BAW) resonator including a phononic crystal acoustic mirror (PCAM), the PCAM including a first arrangement of a first plurality of members in a first region, and a second arrangement of a second plurality of members in a second region, the first arrangement different from the second arrangement.

Abstract: Embodiments of the invention include a waveguide structure that includes a first piezoelectric transducer that is positioned in proximity to a first end of a cavity of an organic substrate. The first piezoelectric transducer receives an input electrical signal and generates an acoustic wave to be transmitted with a transmission medium. A second piezoelectric transducer is positioned in proximity to a second end of the cavity. The second piezoelectric transducer receives the acoustic wave from the transmission medium and generates an output electrical signal.

Abstract: A bulk acoustic wave (BAW) resonator includes: a plurality of acoustic reflectors disposed in a substrate; a lower electrode disposed over the plurality of acoustic reflectors; a piezoelectric layer disposed over the lower electrode; and a plurality of upper electrodes, disposed over the piezoelectric layer. One of the plurality of upper electrodes is formed over a respective one of the plurality of acoustic reflectors. Each of the plurality of upper electrodes, the piezoelectric layer, the lower electrode, and each of the acoustic reflectors form an individual active area.

Abstract: An acoustic resonator is provided in which loss of acoustic waves in a transverse direction may be reduced through a cavity formed in an acoustic resonance unit including a first electrode, a piezoelectric layer, and a second electrode, and in which acoustic waves in a longitudinal direction may be reduced by forming an air gap between the acoustic resonance unit and a substrate. Whereby, a quality factor may be improved.

Abstract: The invention relates to an electronic component having a layer sequence, which comprises at least a first electrode (10), a second electrode (20) and an active region (30) and contains monoatomic carbon layers at least in sub-regions.

Abstract: The various technologies presented herein relate to various hybrid phononic-photonic waveguide structures that can exhibit nonlinear behavior associated with traveling-wave forward stimulated Brillouin scattering (forward-SBS). The various structures can simultaneously guide photons and phonons in a suspended membrane. By utilizing a suspended membrane, a substrate pathway can be eliminated for loss of phonons that suppresses SBS in conventional silicon-on-insulator (SOI) waveguides. Consequently, forward-SBS nonlinear susceptibilities are achievable at about 3000 times greater than achievable with a conventional waveguide system. Owing to the strong phonon-photon coupling achievable with the various embodiments, potential application for the various embodiments presented herein cover a range of radiofrequency (RF) and photonic signal processing applications. Further, the various embodiments presented herein are applicable to applications operating over a wide bandwidth, e.g. 100 MHz to 50 GHz or more.

Abstract: An apparatus comprises a thin-film bulk acoustic resonator such as including an acoustic mirror, a piezoelectric region acoustically coupled to the acoustic mirror, and first and second conductors electrically coupled to the piezoelectric region. In an example, an integrated circuit substrate can include an interface circuit connected to the first and second conductors of the resonator, the integrated circuit substrate configured to mechanically support the resonator. An example can include an array of such resonators co-integrated with the interface circuit and configured to detect a mass change associated with one or more of a specified protein binding, a specified antibody-antigen coupling, a specified hybridization of a DNA oligomer, or an adsorption of specified gas molecules.

Abstract: An oscillating device for a fill-level measurement system includes a drive element in operative connection with a diaphragm. The drive housing receives the drive element at an open-ended front side and includes a first housing part and a second housing part in an operative axially interfitting arrangement proximate the drive element. A flexible conductor in operative connection joins the drive element and extends in a sung-fit arrangement between the first housing part and the second housing part providing improved operative performance.

Abstract: An acoustic resonator includes a substrate and a first composite electrode disposed over the substrate. The first composite electrode includes first and second electrically conductive layers and a first temperature compensating layer disposed between the first and second electrically conductive layers. The second electrically conductive layer forms a first electrical contact with the first electrically conductive layer on at least one side of the first temperature compensating layer, and the first electrical contact electrically shorts a first capacitive component of the first temperature compensating layer.

Abstract: A method of forming a double bulk acoustic resonator structure comprises forming a first electrode on a substrate, forming a first piezoelectric layer on the first electrode, forming a second electrode on the first piezoelectric layer, forming a second piezoelectric layer on the second electrode, and forming a third electrode on the second piezoelectric layer. The first and second piezoelectric layers are formed by a sputter deposition process using at least one sputter target comprising a combination of scandium and aluminum.

Abstract: A microelectromechanical (MEM) resonator includes a resonant cavity disposed in a first layer of a first solid material disposed on a substrate and a first plurality of reflectors disposed in the first layer in a first direction with respect to the resonant cavity and to each other. Each of the first plurality of reflectors comprises an outer layer of a second solid material and an inner layer of a third solid material. The inner layer of each of the first plurality of reflectors is adjacent in the first direction to the outer layer of each reflector and to either the outer layer of an adjacent reflector or the resonant cavity.

Abstract: A bulk acoustic wave (BAW) resonator is constructed to reduce phase and amplitude ripples in a frequency response. The BAW resonator is fabricated on a substrate 400 ?m thick or less, preferably approximately 325 ?m, having a first side and a polished second side with a peak-to-peak roughness of approximately 1000 A. A Bragg mirror having alternate layers of a high acoustic impedance material, such as tungsten, and a low acoustic impedance material is fabricated on the first side of the substrate. A BAW resonator is fabricated on the Bragg mirror. A lossy material, such as epoxy, coats the second side of the substrate opposite the first side. The lossy material has an acoustic impedance in the range of 0.01× to 1.0× the acoustic impedance of the layers of high acoustic impedance material.

Abstract: A thin film bulk acoustic resonator (FBAR) includes a first electrode stacked on a substrate over a cavity, a piezoelectric layer stacked on the first electrode, and a second electrode stacked on the piezoelectric layer. Multiple lateral features are formed on a surface of the second electrode, the lateral features including multiple stepped structures.

Abstract: Provided are low pass filters using a bulk acoustic wave resonator (BAWR). A low pass filter may include an input terminal configured to be connected with a first radio frequency (RF) device, an output terminal configured to be connected with a second RF device, a parallel segment including a first BAWR, a third BAWR, and a fifth BAWR that may be connected in parallel with each other to a reference potential, a first series segment having a second BAWR and a first inductor, and a second series segment having a fourth BAWR and a second inductor, and connected in series with the first series segment.

Abstract: An acoustic resonator comprises a substrate having a trench with lateral boundaries, a first electrode formed on the substrate over the trench and having lateral edges that are laterally offset from the lateral boundaries of the trench by a first distance, a first piezoelectric layer formed on the first electrode, a second electrode formed on the first piezoelectric layer and having edges that are laterally aligned inside the lateral boundaries of the trench, a second piezoelectric layer located on the second electrode, and a third electrode located on the second piezoelectric layer and having edges that are laterally offset from the edges of the second electrode.

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: In one aspect of the invention, an acoustic device has a first coupled resonator filter (CRF) and a second CRF electrically coupled to one another in series. Each CRF has an input port, an output port, a bottom film bulk acoustic resonator (FBAR), an acoustic decoupler formed on the bottom FBAR, and a top FBAR formed on the acoustic decoupler. Each FBAR has a bottom electrode, a piezoelectric layer formed on the bottom electrode, and a top electrode formed on the piezoelectric layer. The decoupling layer capacitance arising between the two electrodes enclosing the acoustic decoupler in a CRF is configured to achieve targeted filter response. A compensating capacitance is introduced to improve the amplitude and phase imbalance performance of an unbalanced to balanced CRF by eliminating the existence of asymmetric port-to-ground or feedback capacitance at the balanced output port produced by the decoupling layer capacitance.

Abstract: A filter includes a first port, a second port, a first fractal curve based filter element coupled to the first port, and a second fractal curve based filter element coupled to the second port. The first fractal curve based filter element has first electromagnetic properties and the second fractal curve based filter element has second electromagnetic properties. The first fractal curve based filter element is electromagnetically coupled to the second fractal curve based filter element to filter radio frequency (RF) signals.

Abstract: An acoustic wave bandpass filter comprises at least two bulk acoustic wave resonators, laterally coupled to each other acoustically, each resonator including a film of piezoelectric material and at least a first electrode and/or a second electrode, said bulk waves propagating in a direction perpendicular to the plane of the film of piezoelectric material, characterized in that: it further comprises at least a first phononic crystal structure between said resonators such that the transmission coefficient of the lateral acoustic waves can be decreased in a direction parallel to the plane of the piezoelectric film; and the first phononic crystal structure is formed in a matrix of dielectric material or with patterns made from dielectric material.

Abstract: Methods of reducing phase and amplitude ripples in a BAW resonator frequency response by providing a substrate, fabricating a Bragg mirror having alternate layers of a high acoustic material and a low acoustic material on a first surface of the substrate, fabricating a BAW on the Bragg mirror, and coating a second side of the substrate opposite the first side with a lossy material having an acoustic impedance in the range of 0.01× to 1.0× the acoustic impedance of the layers of high impedance material, the second surface of the substrate being a polished surface. Various embodiments are disclosed.

Abstract: A device includes: a first electrode having a first electrode thickness; a first acoustic propagation layer disposed on the first electrode, the first piezo-electric layer having a first acoustic propagation layer thickness; a second electrode having a second electrode thickness; a second piezo-electric layer disposed on the first electrode, the second piezo-electric layer having a second acoustic propagation layer thickness; and a third electrode having a third electrode thickness, wherein the second electrode thickness is between 1.15 and 1.8 times the first electrode thickness. The first and third electrode thicknesses may be equal to each other, and the first and second piezo-electric layer thicknesses may be equal to each other. The first and third electrodes may be connected together to provide two acoustic resonators in parallel with each other.

Abstract: A branching filter includes a ladder-type elastic wave filter unit connected between an antenna terminal and a transmission signal terminal and a longitudinally coupled resonator-type elastic wave filter unit connected between an antenna terminal and first and second balanced reception signal terminals while maintaining the isolation characteristics between the transmission signal terminal and the first and second reception signal terminals. In a duplexer, a transmission signal propagation direction is perpendicular or substantially perpendicular to each of a first reception signal propagation direction and a second reception signal propagation direction.

Abstract: Disclosed herein is a resonator including, a vibrating portion having a conductor portion, and three or more insulating portions provided so as to electrically separate the conductor portion into a plurality of blocks, wherein when a potential difference is caused across both ends in each of the three or more insulating portions, the vibrating portion carries out a resonance vibration based on a longitudinal vibration in accordance with a frequency of an A.C. signal inputted to each of corresponding ones of the plurality of blocks in the conductor portion.

Abstract: In accordance with a representative embodiment, a bulk acoustic wave (BAW) resonator structure, comprises: a first BAW resonator comprising a first lower electrode, a first upper electrode and a first piezoelectric layer disposed between the first lower electrode and the first upper electrode; a second BAW resonator comprising a second lower electrode, a second upper electrode and a second piezoelectric layer disposed between the second lower electrode and the second upper electrode; an acoustic coupling layer disposed between the first BAW resonator and the second BAW resonator; and a bridge disposed between the first lower electrode of the first BAW resonator and the second upper electrode of the second BAW resonator. An inner raised region or an outer raised region, or both are disposed over the second upper electrode.

Abstract: In a representative embodiment, a bulk acoustic wave (BAW) resonator comprises: a cavity provided in a first layer and having a perimeter bordering an active region of the BAW resonator; a distributed Bragg reflector (DBR) bordering the cavity, wherein the first layer is one of the layers of the DBR; a first electrode disposed over the substrate; a first piezoelectric layer disposed over the first electrode; a second electrode disposed over the first piezoelectric layer; a second piezoelectric layer disposed over the second electrode; a third electrode disposed over the second piezoelectric layer; and a bridge disposed between the first electrode and the third electrode.

Abstract: A film bulk acoustic resonator (FBAR) structure includes a first electrode disposed over a substrate, a piezoelectric layer disposed over the first electrode, and a second electrode disposed over the first piezoelectric layer. A bridge is disposed between the first electrode and the piezoelectric layer.

Abstract: In accordance with a representative embodiment, a bulk acoustic wave (BAW) resonator structure, comprises: a first BAW resonator comprising a first lower electrode, a first upper electrode and a first piezoelectric layer disposed between the first lower electrode and the first upper electrode; a second BAW resonator comprising a second lower electrode, a second upper electrode and a second piezoelectric layer disposed between the second lower electrode and the second upper electrode; an acoustic coupling layer disposed between the first BAW resonator and the second BAW resonator; and a bridge disposed between the first lower electrode of the first BAW resonator and the second upper electrode of the second BAW resonator.

Abstract: A bulk acoustic wave (BAW) structure includes a first electrode disposed over a substrate, a piezoelectric layer disposed over the first electrode, and a second electrode disposed over the first piezoelectric layer. A bridge is formed within the piezoelectric layer, where the bridge is surrounded by piezoelectric material of the piezoelectric layer.

Abstract: The present invention in one aspect relates to an acoustic wave resonator having an acoustic reflector, a piezoelectric layer, a composite structure having a first electrode, a temperature compensation layer formed on the first electrode, having one or more vias or trenches formed therein, and a second electrode formed on the temperature compensation layer and electrically connected to the first electrode at least through the one or more vias or trenches, and a third electrode, where the composite structure is disposed under the piezoelectric layer, on the piezoelectric layer, or inside the piezoelectric layer.