Abstract: A surface acoustic wave (SAW) filter package structure includes a dielectric substrate having a dielectric layer, a first patterned conductive layer, a second patterned conductive layer, and a conductive connection layer. The conductive connection layer is electrically connected between the first patterned conductive layer and the second patterned conductive layer, which are disposed at opposite sides of the dielectric layer. The second patterned conductive layer has a finger electrode portion. An active surface of a chip is faced toward the finger electrode portion. A polymer sealing frame is disposed between the chip and the dielectric substrate and surrounds the periphery of the chip to form a chamber together with the chip and the dielectric substrate. The mold sealing layer is disposed on the dielectric substrate and covers the chip and the polymer sealing frame. A manufacturing method of the SAW filter package structure is also disclosed.

Abstract: Multiplexers are disclosed. A multiplexer can include a first filter and a second filter that are coupled to a common node. The second filter can include a first type of acoustic wave resonators (e.g., bulk acoustic wave resonators) and a series acoustic wave resonator of a second type (e.g., a surface acoustic wave resonator) that is coupled between the acoustic wave resonators of the first type and the common node. The first filter can provide a single-ended radio frequency signal. In certain embodiments, the first filter can be a receive filter and the second filter can be a transmit filter.

Abstract: An acoustic wave device includes a (111)-oriented silicon substrate, a silicon nitride layer, a silicon oxide layer, a lithium tantalate layer, and an IDT electrode on the lithium tantalate layer. When the wavelength determined by the electrode finger pitch of the IDT electrode is ?, the thickness of the silicon nitride layer, SiN [?], the thickness of the silicon oxide layer, SiO2 [?], the thickness of the lithium tantalate layer, LT [?], and one of the Euler angles of the lithium tantalate layer, LT? [deg.], are thicknesses and an angle in ranges in which the phase of a first higher-order mode is about ?20° or less.

Abstract: An improved SAW (SAWR) resonator having an improved power durability and heat resistance and a protection to prevent device failure is provided. The SAW resonator has a carrier substrate (S) and an electrode structure (ES, EF) on a piezoelectric material (PM, PL). Further, the resonator has a shunt path (PCPP) parallel to the electrode structure and provided to enable an RF signal to bypass the electrode structure. The shunt path has a temperature dependent conductance with negative temperature coefficient of resistance.

Abstract: Aspects of this disclosure relate to an acoustic wave resonator with transverse mode suppression. The acoustic wave resonator can include a piezoelectric layer, an interdigital transducer electrode, a temperature compensation layer, and a mass loading strip. The mass loading strip can be a conductive strip. The mass loading strip can overlap edge portions of fingers of the interdigital transducer electrode. A layer of the mass loading strip can have a density that is at least as high as a density of a material of the interdigital transducer electrode. The material of the interdigital transducer can impact acoustic properties of the acoustic wave resonator.

Abstract: A bulk acoustic wave (BAW) resonator includes a substrate, a piezoelectric layer disposed above the substrate, a first electrode disposed below the piezoelectric layer, a second electrode disposed above the piezoelectric layer, a first dielectric layer, a second dielectric layer, and a third dielectric layer disposed between the substrate and the piezoelectric layer, and a bonding layer disposed between the third dielectric layer and the substrate. The first dielectric layer is disposed below the piezoelectric layer and includes a cavity. The third dielectric layer is disposed below the first dielectric layer and includes a protruding structure protruding towards the piezoelectric layer. The second dielectric layer overlays the third dielectric layer including the protruding structure, the second dielectric layer and the protruding structure of the third dielectric layer constituting a double-wall boundary structure surrounding the cavity.

Abstract: A multiplexer includes a transmission-side filter electrically connected to a common terminal and a transmission input terminal, and a transmission-side filter electrically connected to the common terminal and a transmission input terminal. The transmission-side filter includes a plurality of series arm resonators and a plurality of parallel arm resonators. Capacitance elements are respectively electrically connected in parallel to the series arm resonator and the parallel arm resonator, which are connected most proximately to the common terminal. IDT electrodes of a series arm resonator and a parallel arm resonator connected most proximately to the common terminal do not include a thinning electrode, and others of the series arm resonators and the parallel arm resonators include thinning electrodes.

Abstract: An RF circuit device using modified lattice, lattice, and ladder circuit topologies. The devices can include four resonator devices and four shunt resonator devices. In the ladder topology, the resonator devices are connected in series from an input port to an output port while shunt resonator devices are coupled the nodes between the resonator devices. In the lattice topology, a top and a bottom serial configurations each includes a pair of resonator devices that are coupled to differential input and output ports. A pair of shunt resonators is cross-coupled between each pair of a top serial configuration resonator and a bottom serial configuration resonator. The modified lattice topology adds baluns or inductor devices between top and bottom nodes of the top and bottom serial configurations of the lattice configuration. These topologies may be applied using single crystal or polycrystalline bulk acoustic wave (BAW) resonators.

Abstract: A method for packaging chips includes: flip-chip bonding a plurality of filter chips to be packaged on a substrate to be packaged; applying a first mold material layer on the filter chips to be packaged; applying a second mold material layer on a side of the first mold material layer away from the filter chip to be packaged, the first mold material layer and the second mold material layer forming a first mold layer; thinning the first mold material layer and the second mold material layer to expose substrates of the filter chips to be packaged, and thinning the substrates of the filter chips to be packaged to a preset thickness; applying a second mold layer on the exposed substrates of the filter chips to be packaged to obtain a mold structure; and cutting the mold structure into a plurality of particle chips.

Abstract: An RF circuit device using modified lattice, lattice, and ladder circuit topologies. The devices can include four resonator devices and four shunt resonator devices. In the ladder topology, the resonator devices are connected in series from an input port to an output port while shunt resonator devices are coupled the nodes between the resonator devices. In the lattice topology, a top and a bottom serial configurations each includes a pair of resonator devices that are coupled to differential input and output ports. A pair of shunt resonators is cross-coupled between each pair of a top serial configuration resonator and a bottom serial configuration resonator. The modified lattice topology adds baluns or inductor devices between top and bottom nodes of the top and bottom serial configurations of the lattice configuration. These topologies may be applied using single crystal or polycrystalline bulk acoustic wave (BAW) resonators.

Abstract: A filter device includes a first path, a second path, and a capacitor. The first path includes at least one ladder filter circuit and connects a first terminal and a second terminal. The at least one ladder filter circuit includes a parallel arm resonator connected to a ground terminal. The second path includes a grounded resonator and is connected in parallel with any of the at least one ladder filter circuit. One end of the capacitor is connected to the second path, and the other end of the capacitor is connected to a third path which connects the parallel arm resonator and the ground terminal.

Abstract: Techniques are disclosed for forming high frequency film bulk acoustic resonator (FBAR) devices having multiple resonator thicknesses on a common substrate. A piezoelectric stack is formed in an STI trench and overgrown onto the STI material. In some cases, the piezoelectric stack can include epitaxially grown AlN. In some cases, the piezoelectric stack can include single crystal (epitaxial) AlN in combination with polycrystalline (e.g., sputtered) AlN. The piezoelectric stack thus forms a central portion having a first resonator thickness and end wings extending from the central portion having a different resonator thickness. Each wing may also have different thicknesses. Thus, multiple resonator thicknesses can be achieved on a common substrate, and hence, multiple resonant frequencies on that same substrate. The end wings can have metal electrodes formed thereon, and the central portion can have a plurality of IDT electrodes patterned thereon.

Abstract: There are disclosed matrix filters having an input port and sub-filters connected between the input port and respective output ports. Each of the sub-filters includes a ladder circuit with n transversely-excited film bulk acoustic resonator (XBAR) series elements and n?1 capacitor shunt elements, where n, the order of the sub-filter, is an integer greater than 2. The sub-filters having noncontiguous passbands.

Abstract: A multiplexer includes: first and second substrates overlapping with each other with an air gap interposed therebetween; a first filter disposed on the first substrate and including first series resonators connected in series with a first path, and first parallel resonators; and a second filter disposed on the second substrate and including second series resonators connected in series with a second path, and second parallel resonators connected between the second path and a ground, each of the second series resonators and the second parallel resonators including a piezoelectric film, a first electrode interposed between the piezoelectric film and the second substrate, a second electrode interposed between the piezoelectric film and the air gap, and a resonance region, in at least one second parallel resonator, the first electrode being coupled to the second path, the second electrode being coupled to the ground, the resonance region overlapping with the first path.

Abstract: The invention provides a filter device, an RF front-end device and a wireless communication device. The filter device comprises a substrate, at least one resonance device, a passive device and a connector, wherein the at least one resonance device has a first side and a second side opposite to the first side, the substrate is located on the first side, and the passive device is located on the second side. The at least one resonance device is connected to the passive device through the connector. The RF filter device formed by integrating the resonance device (such as an SAW resonance device or a BAW resonance device) and the passive device (such as an IPD) in one die can broaden the passband width, has a high out-of-band rejection, and occupies less space in an RF front-end chip.

Abstract: An RF filter comprising a resonator element and a polymer composition is provided. The polymer composition contains an aromatic polymer and has a melting temperature of about 240° C. or more. The polymer composition exhibits a dielectric constant of about 5 or less and dissipation factor of about 0.05 or less at a frequency of 10 GHz.

Abstract: The present invention relates to a surface acoustic wave device package and a method of manufacturing the same, and more specifically, to a method of manufacturing a miniaturized surface acoustic wave device package.

Abstract: In an acoustic wave device, an interdigital transducer electrode is disposed on a piezoelectric substrate with a reverse velocity surface having an elliptic shape, and a dielectric film is disposed to cover the interdigital transducer electrode. Assuming an electrode density (%) of the interdigital transducer electrode to be y (%) and a wavelength-normalized film thickness 100h/? (%) of the interdigital transducer electrode to be x (%), the wavelength-normalized film thickness x of the interdigital transducer electrode takes a value not less than x satisfying y=0.3452x2?6.0964x+36.262 depending on the electrode density of the interdigital transducer electrode.

Abstract: An RF circuit device using modified lattice, lattice, and ladder circuit topologies. The devices can include four resonator devices and four shunt resonator devices. In the ladder topology, the resonator devices are connected in series from an input port to an output port while shunt resonator devices are coupled the nodes between the resonator devices. In the lattice topology, a top and a bottom serial configurations each includes a pair of resonator devices that are coupled to differential input and output ports. A pair of shunt resonators is cross-coupled between each pair of a top serial configuration resonator and a bottom serial configuration resonator. The modified lattice topology adds baluns or inductor devices between top and bottom nodes of the top and bottom serial configurations of the lattice configuration. These topologies may be applied using single crystal or polycrystalline bulk acoustic wave (BAW) resonators.

Abstract: A filter device, an RF front-end device and a wireless communication device are provided. The filter device includes a substrate, a passive device and at least one resonance device, wherein the passive device has a first side and a second side opposite to the first side, the substrate is located on the first side, and the at least one resonance device is located on the second side. The RF filter device formed by integrating the resonance device (such as an SAW or BAW resonance device) and the passive device (such as an IPD) can broaden the pass-band width, has a high out-of-band rejection, and occupies less space in an RF front-end chip.

Abstract: A method for producing an adjustable bulk acoustic wave resonator comprising a transducer stack (E1) and a tuning stack (E2). According to the invention, transducer stack (E1) includes two defined electrodes (4, 6) and piezoelectric material (2), and stack (E2) includes a layer of piezoelectric material (8) and two defined electrodes (10, 12). The method includes: a) production of the transducer stack; b) formation of an electrically insulating layer on an electrode (6) of the transducer stack; c) formation of a defined electrode (10) of the tuning stack on the electrically insulting layer such that it is aligned with the electrodes of the transducer stack; d) assembly, on the electrode (10), of a substrate of piezoelectric material; e) fracturing of the substrate of piezoelectric material; and f) formation of the other defined electrode (12) of the tuning stack, aligned with the defined electrode (10).

Abstract: A surface acoustic wave filter includes series and parallel arm resonance sections. The series arm resonance section is in a series arm. The parallel arm resonance section is in a parallel arm. The series arm resonance section includes one or more surface acoustic wave devices. Each surface acoustic wave device includes a first resonator group and a second resonator group. The first and second resonator groups are connected in parallel and include surface acoustic wave resonators. The first resonator group includes at least one surface acoustic wave resonator. The second resonator group includes a greater number of surface acoustic wave resonators than the at least one surface acoustic wave resonator in the first resonator group. The resonant frequency of the surface acoustic wave resonator in the first resonator group is higher than the resonant frequency of the surface acoustic wave resonators in the second resonator group.

Abstract: A film bulk acoustic wave resonator (FBAR) comprises a recessed frame region including an undulating perimeter.

Abstract: An electronic device comprises a first substrate having a first surface bonded to a first surface of a second substrate, one or more acoustic wave devices disposed on the first surface of each of the first substrate and the second substrate, and a thermally conductive layer disposed on a second surface of the first substrate opposite the first surface of the first substrate. The thermally conductive layer has a higher thermal conductivity than a material of which the first substrate is formed to reduce an operating temperature of the first substrate.

Abstract: RF filtering circuitry comprises a first node, a second node, and a series signal path between the first node and the second node. A number of acoustic resonators are coupled to one or more of the first node and the second node via the series signal path. A first one of the acoustic resonators is associated with a first quality factor and a first electromechanical coupling coefficient. A second one of the acoustic resonators is associated with a second quality factor and a second electromechanical coupling coefficient. The first quality factor is different from the second quality factor and the first electromechanical coupling coefficient is different from the second electromechanical coupling coefficient.

Abstract: An acoustic structure is provided. The acoustic structure includes an acoustic resonator structure configured to resonate in a series resonance frequency (e.g., passband frequency) to pass a signal, or cause a series capacitance to block the signal in a parallel resonance frequency (e.g., stopband frequency). The parallel resonance frequency may become higher than the series resonance frequency when the tunable capacitance is lesser than or equal to two times of the series capacitance (CTune?2C0), or lower than the series resonance frequency when the tunable capacitance is greater than two times of the series capacitance (CTune>2C0). In this regard, the acoustic structure can be configured to include a tunable reactive circuit to generate the tunable capacitance (CTune) to adjust the parallel resonance frequency. As such, it may be possible to flexibly configure the acoustic resonator structure to block the signal in desired stopband frequencies.

Abstract: Embodiments of this disclosure relate to methods of manufacturing acoustic wave components that include acoustic wave resonators that share a substrate. Laser light can be applied to alter a region of the substrate that is located between two of the acoustic wave resonators. Altering the region with laser light can reduce coupling between the two acoustic resonators through the substrate. The substrate can be monolithic after laser the light is applied.

Abstract: An acoustic resonator includes: a substrate; a resonant region including a first electrode, a piezoelectric layer, and a second electrode disposed on the substrate, and a reflective layer disposed along a periphery of the resonant region; and a connection electrode extending from the second electrode. The reflective layer includes a second section disposed between the resonant region and the connection electrode, and a first section, and a cross-sectional area of the first section is different than a cross-sectional area of the second section.

Abstract: A filter circuit includes a plurality of first resonators provided in a series arm, a plurality of second resonators provided in a parallel arm, and at least one or more third resonators that are electrically connected in series with each other and are electrically connected in parallel with the first resonators in the series arm. An anti-resonant frequency of the third resonators is lower than an anti-resonant frequency of the second resonators. A combined capacitance of the at least one or more third resonators electrically connected in series with each other is smaller than an electrostatic capacitance of the second resonators.

Abstract: A multiplexer includes a common terminal, a first terminal, a second terminal, a first filter device including acoustic wave resonators including series resonators and parallel resonators, an inductor provided between an acoustic wave resonator and the first terminal, and a second filter device. The first filter device further includes a first ground terminal to which a parallel resonator is electrically connected, a second ground terminal to which the parallel resonators are electrically connected, and a wiring provided between the inductor and an acoustic wave resonator. In the first filter device, the wiring is electrically connected to the first ground terminal, and the first ground terminal is not connected to the second ground terminal.

Abstract: A bulk-acoustic wave resonator includes: a first electrode; a piezoelectric layer at least partially disposed on an upper portion of the first electrode; and a second electrode disposed to cover at least a portion of the piezoelectric layer. The second electrode includes a frame disposed at an edge of an active region of the bulk-acoustic wave resonator, and the first electrode, the piezoelectric layer and the second electrode are disposed to overlap one another at the edge of the active region. The frame includes a wall disposed at the edge of the active region and a trench formed on an internal side of the wall. An internal boundary line of the trench has a concave-convex shape in a plane parallel to an upper surface of the frame.

Abstract: A filter module includes an inductor, a filter including first wiring, and second wiring between the inductor and the first wiring and being a direct-current floating potential. The inductor and the first wiring are magnetically coupled, the inductor and the second wiring are magnetically coupled, and the first wiring and the second wiring are capacitively coupled.

Abstract: Disclosed is a Bulk Acoustic Wave (BAW) filter structure with a conductive bridge forming an electrical loop with an electrode for reduced electrical losses. In exemplary aspects disclosed herein, the BAW filter structure includes a transducer with electrodes, a piezoelectric layer between the electrodes, and at least one conductive bridge offset from at least a portion of one of the electrodes by an insulating volume. The conductive bridge forms a first electrical loop between a medial end and a distal end of the electrode. Such a configuration reduces electrical resistance, heat resistance, and/or ohmic losses for improved electrical loss of the BAW filter structure.

Abstract: An acoustic wave filter includes a first signal terminal, an antenna terminal, a ladder-type filter connected between the first signal terminal and the antenna terminal and including one or more serial resonators and one or more parallel resonators connected in a ladder shape, and a capacitor part and an inductor part which are connected in series between the first signal terminal and a reference potential.

Abstract: A transmission filter is arranged in a first filter region and has one or more acoustic wave resonators, a plurality of terminal electrodes, and a plurality of wires. A reception filter is arranged in a second filter region and has one or more acoustic wave resonators, a plurality of terminal electrodes, and a plurality of wires. The first filter region and the second filter region are arranged adjacently to each other and have at least sides constituting a pair and opposing to each other. At least either one of the first filter region and the second filter region has no wire extending along one side in a forbidden region that is defined by a width including a terminal electrode nearest to the one side, along the one side and over the one side opposing to the other filter region.

Abstract: A transmit filter circuit includes an input terminal, an output terminal, plural series arm resonators, and a parallel arm resonator. The input terminal receives a transmit signal. The output terminal is electrically connected to an antenna. The plural series arm resonators are electrically connected in series with each other on a line between the input and output terminals. The plural series arm resonators include first and second series arm resonators. The first series arm resonator is closest to the output terminal. The second series arm resonator is second closest to the output terminal. A first end of the parallel arm resonator is electrically connected to a node between the first and second series arm resonators. A reference potential is provided to a second end of the parallel arm resonator. The resonant frequency of the first series arm resonator is higher than that of the second series arm resonator.

Abstract: Acoustic resonator devices and filters. An acoustic resonator includes a substrate having a surface and a lithium niobate plate. A back surface of the lithium niobate plate is attached the substrate except for a portion of the lithium niobate plate forming a diaphragm that spans a cavity in the substrate. An interdigital transducer (IDT) is formed on a front surface of the lithium niobate plate such that interleaved fingers of the IDT are disposed on the diaphragm. The IDT and the lithium niobate plate configured such that a radio frequency signal applied to the IDT excites a shear primary acoustic mode within the diaphragm. Euler angles of the lithium niobate plate are [0°, ?, 0°], where ? is greater than or equal to 40° and less than or equal to 70°.

Abstract: A longitudinally coupled resonator elastic wave filter is disposed on a piezoelectric substrate. IDT electrodes include first and second busbars. An inorganic insulating layer is provided on at least one side in a direction perpendicular or substantially perpendicular to an elastic wave propagation direction to cover the first or second busbars, and a first wiring line is disposed on the inorganic insulating layer to extend in the elastic wave propagation direction. A second wiring line three-dimensionally crosses the first wiring line with the inorganic insulating layer interposed therebetween. The first wiring line is connected to busbars, which are connected to the same potential, by extending through the inorganic insulating layer.

Abstract: Embodiments of this disclosure relate to reducing coupling between acoustic wave resonators. An isolation region of a substrate can be located between acoustic wave resonators. The isolation region can reduce capacitive coupling through the substrate between the acoustic wave resonators. In certain embodiments, the isolation region can be located between acoustic wave resonators of different filters to thereby increase isolation between the filters.

Abstract: A laterally excited bulk acoustic wave device is disclosed. The laterally excited bulk acoustic wave device can include a support substrate, a solid acoustic mirror on the support substrate, a piezoelectric layer on the solid acoustic mirror, and an interdigital transducer electrode on the piezoelectric layer. The interdigital transducer electrode is arranged to laterally excite a bulk acoustic wave.

Abstract: An RF circuit device using modified lattice, lattice, and ladder circuit topologies. The devices can include a plurality of resonator devices and a plurality of resonator devices. In the ladder topology, the resonator devices are connected in series from an input port to an output port while shunt resonator devices are coupled the nodes between the resonator devices. In the lattice topology, a top and a bottom serial configurations each includes a pair of resonator devices that are coupled to differential input and output ports. A pair of shunt resonators is cross-coupled between each pair of a top serial configuration resonator and a bottom serial configuration resonator. The modified lattice topology adds baluns or inductor devices between top and bottom nodes of the top and bottom serial configurations of the lattice configuration. These topologies may be applied using single crystal or polycrystalline bulk acoustic wave (BAW) resonators.

Abstract: An RF circuit device using modified lattice, lattice, and ladder circuit topologies. The devices can include a plurality of resonator devices and a plurality of resonator devices. In the ladder topology, the resonator devices are connected in series from an input port to an output port while shunt resonator devices are coupled the nodes between the resonator devices. In the lattice topology, a top and a bottom serial configurations each includes a pair of resonator devices that are coupled to differential input and output ports. A pair of shunt resonators is cross-coupled between each pair of a top serial configuration resonator and a bottom serial configuration resonator. The modified lattice topology adds baluns or inductor devices between top and bottom nodes of the top and bottom serial configurations of the lattice configuration. These topologies may be applied using single crystal or polycrystalline bulk acoustic wave (BAW) resonators.

Abstract: An acoustic wave device includes: a Y-cut X-propagation lithium tantalate substrate having a cut angle of 5° or greater and 18° or less; and a grating electrode that is formed of one or more metal films stacked on the lithium tantalate substrate, a number of the one or more metal films being n (n is a natural number), excites an acoustic wave, and meets a condition: 0.16 ? ? ? ? i = 1 n ? ? ( hi × ? ? ? i ? ? ? 0 ) ? 0.24 ? ? where ?i represents a density of each metal film of the one or more metal films, hi represents a film thickness of the each metal film, ?0 represents a density of Mo, and ? represents a pitch.

Abstract: An acoustic wave filter includes series arm resonators each including an IDT electrode on a piezoelectric substrate. Resonant frequencies of the series arm resonators are positioned within the pass band of the acoustic wave filter. The IDT electrode includes a pair of comb-shaped electrodes. Each of the comb-shaped electrodes includes electrode fingers and a busbar electrode. The electrode fingers extend in a direction intersecting a propagation direction of acoustic waves and are parallel with each other. One end of an electrode finger and one end of another electrode finger are connected with each other by the busbar electrode. The IDT electrode of the series arm resonator with the lowest anti-resonant frequency includes two or more withdrawal-weighted floating electrodes without any of the electrode fingers of one of the comb-shaped electrodes interposed therebetween.

Abstract: A SAW filter is a high-frequency filter including a common terminal, a transmission terminal and a reception terminal through which high-frequency signals are inputted and outputted. The SAW filter includes: a first filter circuit having a first frequency band as a pass band, and connected to the common terminal and the transmission terminal; a second filter circuit having a second frequency band different from the first frequency band as a pass band, and connected to the common terminal and the reception terminal; an antenna connected to the common terminal; and at least one inductor connected in series between the common terminal and the first filter circuit or the second filter circuit.

Abstract: Aspects of this disclosure relate to an acoustic wave resonator having at least two resonant frequencies. An acoustic wave filter can include series acoustic wave resonators and shunt acoustic wave resonators together arranged to filter a radio frequency signal. A first shunt resonator of the shunt acoustic wave resonators can include an interdigital transducer electrode and have at least a first resonant frequency and a second resonant frequency. Related acoustic wave resonators, multiplexers, wireless devices, and methods are disclosed.

Abstract: A bulk acoustic resonator includes: a substrate; a first electrode disposed on the substrate; a piezoelectric layer disposed to cover at least a portion of the first electrode; a second electrode disposed to cover at least a portion of the piezoelectric layer; and an insertion layer disposed below a partial region of the piezoelectric layer. A thickness of the first electrode in an active region in which the first electrode, the piezoelectric layer, and the second electrode overlap one another is less than a thickness of a region outside the active region. An angle of inclination of an internal side surface of the insertion layer is different from an angle of inclination of an external side surface of the insertion layer.

Abstract: A film bulk acoustic wave resonator (FBAR) includes a piezoelectric film disposed in a central region defining a main active domain in which a main acoustic wave is generated during operation and in recessed frame regions disposed laterally on opposite sides of the central region, and an electrode disposed on an upper surface of the piezoelectric film, the electrode having a lesser thickness in the recessed frame regions than the thickness of the electrode in the central region to increase a quality factor of the FBAR.

Abstract: A surface acoustic wave device includes a substrate, a first electrode and a second electrode formed on the substrate to extend along a first direction, wherein the first electrode and the second electrode are alternately disposed along the second direction, one end of the first electrode on one side of the first direction is aligned along the second direction, and one end of the second electrode on the other side of the first direction is aligned along the second direction, a temperature compensation film which covers the first electrode and the second electrode, a first additional film formed on the temperature compensation film to vertically overlap a partial region from the one end of the first electrode on the one side of the first direction, and a second additional film formed on the temperature compensation film to vertically overlap a partial region from the one end of the second electrode.

Abstract: The invention combines two filter technologies on a single device using the same substrate there for. On this substrate a filter circuit is arranged that has a ladder-type or a lattice arrangement of series and parallel impedance elements to provide a hybrid filter having for example a band pass function. The impedance elements are chosen from BAW resonators and LC elements.