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.

A crystal resonator plate according to one or more embodiments may include: a vibrating part; an external frame part surrounding the outer periphery of the vibrating part; and a support part connecting the vibrating part to the external frame part. A first excitation electrode is formed on a first main surface of the vibrating part. A second excitation electrode is formed on a second main surface of the vibrating part. The second excitation electrode includes a pair of parallel sides parallel to each other. The first excitation electrode includes protruding parts that protrude outward from a part between the parallel sides the second excitation electrode in plan view. The protruding parts each have an outer edge shape that is not along the parallel sides in plan view.

An RF triplexer 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 to 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.

A method and structure for a transfer process for an acoustic resonator device. In an example, a bulk acoustic wave resonator (BAWR) with an air reflection cavity is formed. A piezoelectric thin film is grown on a crystalline substrate. One or more patterned electrodes are deposited on the surface of the piezoelectric film. An etched sacrificial layer is deposited over the one or more electrodes and a planarized support layer is deposited over the sacrificial layer. The support layer is etched to form one or more cavities overlying the electrodes to expose the sacrificial layer. The sacrificial layer is etched to release the cavities around the electrodes. Then, a cap layer is fusion bonded to the support layer to enclose the electrodes in the support layer cavities.

In a crystal resonator plate (2), a support part (24) extends from only one corner part positioned in the +X direction and in the −Z′ direction of a vibrating part (22) to an external frame part (23) in the −Z′ direction. The vibrating part (22) and at least part of the support part (24) form an etching region (Eg) having a thickness thinner than a thickness of the external frame part (23). A stepped part is formed at a boundary of the etching region (Eg), and a first lead-out wiring (223) is formed over the support part (24) to the external frame part (23) so as to overlap with the stepped part. At least part of the stepped part that is superimposed on the first lead-out wiring (223) is formed so as not to be parallel to the X axis in plan view.

Among a plurality of electrodes for mounting purpose, all of the electrodes for mounting purpose but two paired ones of the electrodes for mounting purpose that are connected to driving electrodes each have a wiring pattern for use in electrical connection between terminals for external connection and mounting terminals of IC. These wiring patterns each have a constricted portion smaller in width than the other portions that prevents the conduction of heat.

In a crystal oscillator accordance to an embodiment, a crystal resonator plate is bonded to, via laminated bonding patterns, a first sealing member covering a first excitation electrode of the crystal resonator plate; and a second sealing member covering a second excitation electrode of the crystal resonator plate. An internal space is formed, which hermetically seals a vibrating part including the first and second excitation electrodes of the crystal resonator plate. The laminated bonding patterns include a laminated sealing pattern annularly formed to surround the vibrating part in plan view so as to hermetically seal the internal space, and a laminated conductive pattern establishing conduction between wiring and electrodes. The laminated conductive pattern is disposed within a closed space surrounded by the laminated sealing pattern. To the laminated sealing pattern, GND potential is applied when the crystal oscillator operates.

A resonator is provided that includes a vibrating section that vibrates in a contour vibration mode, a frame that surrounds at least a portion of the vibrating section, supporting sections extending along a Y-axis direction and connecting the vibrating section and the frame. The vibrating section includes a through hole that extends along an X-axis direction perpendicular to the Y-axis direction such that a coupling section is disposed between the through hole and each of the supporting sections. The length SL of the through hole in the X-axis direction is longer than the length Sd of the coupling section in the Y-axis direction.

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 to 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.

A crystal vibration element that includes a crystal piece that has a prescribed crystal orientation, and a first direction and a second direction in a plan view thereof; and excitation electrodes that are respectively provided on front and rear surfaces of the crystal piece in order to excite a thickness shear vibration in the crystal piece upon application of an alternating electric field. A vibration distribution of the crystal piece has a vibration region that extends in a band-like shape in the second direction of the crystal piece and non-vibration regions that are adjacent to opposed sides of the vibration region in the first direction of the crystal piece.