Abstract: An acoustic wave filter device includes a substrate, first and second acoustic impedance layers, a piezoelectric layer, first and second interdigital transducer electrodes, an input terminal, an output terminal, ground terminals, a series arm circuit, and a parallel arm circuits. The first interdigital transducer electrode at least partially overlaps the first acoustic impedance layer in the plan view. The second interdigital transducer electrode at least partially overlaps the second acoustic impedance layer in the plan view. The series arm circuit is provided on a first path connecting the input terminal and the output terminal and includes the first and second interdigital transducer electrodes. A conductive layer in the first acoustic impedance layer and a conductive layer in the second acoustic impedance layer are electrically insulated from each other.

Abstract: Aspects of this disclosure relate to an acoustic wave resonator with a patterned conductive layer. The acoustic wave resonator can include a piezoelectric layer, an interdigital transducer electrode over the piezoelectric layer, and a temperature compensation layer over the interdigital transducer electrode. The interdigital transducer electrode can include a bus bar and fingers extending from the bus bar. The fingers can each include an edge portion and a body portion. The patterned conductive layer can overlap the edge portions of the fingers. The patterned conductive layer can conductive portions that are spaced apart from each other. A portion of the temperature compensation layer can be positioned between the patterned conductive layer and the interdigital transducer electrode.

Abstract: A tunable bulk acoustic wave (BAW) resonator includes: a first electrode adapted to be coupled to an oscillator circuit; a second electrode adapted to be coupled to the oscillator circuit; and a piezoelectric layer between the first electrode and the second electrode; and a Bragg mirror. The Bragg mirror has: a metal layer; and a dielectric layer between the metal layer and either of the first electrode or the second electrode. The tunable BAW resonator also includes: a radio-frequency (RF) signal source having a first end and a second end, the first end coupled to the first electrode, and the second end coupled to the second electrode; and an amplifier circuit between either the first electrode or the second electrode and the Bragg mirror metal layer.

Abstract: Disclosed is a film bulk acoustic resonator (FBAR) including a substrate, a lower electrode formed above the substrate, a piezoelectric layer formed above the lower electrode, an upper electrode formed above the piezoelectric layer, and a first protection layer formed above the upper electrode. Here, the first protection layer covers the upper electrode while extending downward along a side surface of one end of the upper electrode to cover a certain area of the piezoelectric layer.

Abstract: An acoustic wave device includes a piezoelectric layer, a first electrode, a second electrode, a first divided resonator, a second divided resonator, and a support substrate. The support substrate includes first and second energy confinement layers. The first energy confinement layer at least partially overlaps with a first region of the piezoelectric layer. The second energy confinement layer at least partially overlaps with a second region of the piezoelectric layer. The first and second energy confinement layers are integrally provided in the support substrate.

Abstract: An impedance matching device includes a first dielectric substrate; a first transmission line circuit; a first conductive pad which extends toward the first transmission line circuit on the first dielectric substrate to at least partially vertically overlap the first transmission line circuit: a first reference potential layer; and a first matching load which is electrically connected to the first conductive pad and has a first resistance. An area where the first conductive pad vertically overlaps the first transmission line circuit has a size configured such that a load reactance associated with the first transmission line circuit is equal to or less than a predetermined threshold and an absolute value of a difference between a load resistance associated with the first transmission line circuit and the first resistance is equal to or less than a predetermined resistance threshold.

Abstract: A surface acoustic wave resonator device, its manufacturing method, and a filter are disclosed. The device includes a piezoelectric substrate, and an interdigital transducer on a side of the substrate, having an interdigital electrode region, and including a first interdigital electrode and a first interdigital electrode lead-out part connected to each other, and a second interdigital electrode and a second interdigital electrode lead-out part connected to each other. The first and second interdigital electrodes are located in the interdigital electrode region, extending along a first direction and alternately arranged in a second direction. The first and second interdigital electrode lead-out parts are located on opposite sides of the interdigital electrode region. A first conductive structure and a second conductive structure overlap with end portions of the interdigital electrodes and are electrically connected to the corresponding interdigital electrodes, respectively.

Abstract: Acoustic resonator devices and acoustic filter devices. An acoustic resonator includes a piezoelectric plate having front and back surfaces. A portion of the back surface is attached to a substrate. The piezoelectric plate comprises a diaphragm spanning a cavity. A conductor pattern is formed on the front surface. The conductor pattern includes a multi-mark interdigital transducer (IDT), with fingers of the IDT on the diaphragm.

Abstract: Aspects of this disclosure relate bulk acoustic wave resonators with a patterned mass loading layer at least contributing to a difference in mass loading between a main acoustically active region of the bulk acoustic wave resonator and a recessed frame region of the bulk acoustic wave resonator. Related methods of manufacturing can involve forming the patterned mass loading layer in the main acoustically active region and the recessed frame region in a common processing step such that the patterned mass loading layer has a higher density in the main acoustically active region than in the recessed frame region.

Abstract: Acoustic resonator devices and methods are disclosed. An acoustic resonator device includes a substrate having a surface and a single-crystal piezoelectric plate having front and back surfaces. A back-side dielectric layer is formed on the back surface. An etch-stop layer is sandwiched between the surface of the substrate and the back-side dielectric layer. A portion of the piezoelectric plate, the back-side dielectric layer, and the etch-stop layer forms a diaphragm spanning a cavity in the substrate. An interdigital transducer (IDT) is formed on the front surface of the single-crystal piezoelectric plate with interleaved fingers of the IDT disposed on the diaphragm. The etch-stop layer is impervious to an etch process used to form the cavity.

Abstract: Acoustic resonators and filter devices, and methods of making acoustic resonators and filter devices. An acoustic resonator includes a substrate having a surface and a single-crystal piezoelectric plate having front and back surfaces, the back surface attached to the surface of the substrate except for a portion of the plate forming a diaphragm that spans a cavity in the substrate. An interdigital transducer (IDT) is formed on the front surface with interleaved fingers of the IDT on the diaphragm. The plate and the IDT are configured such that a radio frequency signal applied to the IDT excites a primary shear acoustic mode in the diaphragm. The fingers include a first layer proximate the diaphragm, and a second layer over the first layer. The first and second layers are different metals. A transverse acoustic impedance of the second layer is higher than a transverse acoustic impedance of the first layer.

Abstract: An acoustic wave device that has a better TCF and can improve a resonator Q or impedance ratio is provided. The acoustic wave device includes a substrate 11 containing 70 mass % or greater of silicon dioxide (SiO2), a piezoelectric thin film 12 including LiTaO3 crystal or LiNbO3 crystal and disposed on the substrate 11, and an interdigital transducer electrode 13 disposed in contact with the piezoelectric thin film 12.

Abstract: An acoustic wave device includes an energy confinement layer, a piezoelectric film, and an IDT electrode laminated on a support substrate. Acoustic velocity adjustment films are at least partially provided between the piezoelectric film and the support substrate and are made of a material different from that of the piezoelectric film.

Abstract: A circuit for matching impedance and regulating a voltage of a high radio frequency line across a low voltage device that includes a differential input port, the high radio frequency lines, an internally routed line, a singled ended peak detection circuit, and a single-ended programmable variable impedance using a single-ended programmable variable impedance. The differential input port receives a differential high radio frequency signal using driver buffers. The internally routed line boosts the received differential high-frequency RF signal. The single-ended peak detection circuit detects peak voltages of the differential high-frequency RF signal. Depending on the peak value obtained at the output of the single-ended peak detection circuit, the single-ended programmable variable impedance that matches the impedance of each of high radio frequency lines and regulates the voltage of high radio frequency lines across said low voltage device to a pre-defined voltage.

Abstract: An acoustic wave device includes a support substrate, a piezoelectric film, a functional electrode, and a support. The support substrate includes a cavity. The piezoelectric film is provided on the support substrate to cover the cavity. The functional electrode is provided on the piezoelectric film to overlap the cavity when viewed in a plan view. The support is in the cavity of the support substrate to support the piezoelectric film. The functional electrode includes electrodes arranged in a direction crossing the thickness direction of the piezoelectric film. The electrodes include a first electrode and a second electrode. The first electrode and the second electrode oppose each other in a direction crossing the thickness direction of the piezoelectric film and are connected to different potentials. Adjacent ones of the electrodes overlap each other in a direction orthogonal to a longitudinal direction of the first electrode.

Abstract: Power dividers (or splitters) and power combiners may be implemented using distributed lossy transmission lines that dissipate radio frequency (RF) and other electromagnetic (EM) signal energy. By taking advantage of natural PCB board loss at high operating frequencies, N-way power dividers with matched outputs and good isolation may be implemented without the use of discrete resistors. In one embodiment, a N-way power divider may be at least partially implemented on buried printed circuit board (PCB) layers (e.g., partially embedded) and, in a further embodiment a N-way may be implemented in a manner that is completely internal to the PCB (e.g., completely embedded), without the use of discrete resistors.

Abstract: An electronic device comprises a first surface acoustic wave (SAW) resonator and a second SAW resonator, each including interleaved interdigital transducer (IDT) electrodes, the first and second SAW resonators being formed on a same piezoelectric substrate, the first SAW resonator having IDT electrodes with a different finger pitch than the IDT electrodes of the second SAW resonator; a dielectric material layer disposed on the IDT electrodes of the first and second SAW resonators; and a high velocity layer disposed within the dielectric material layer disposed on the IDT electrodes of the first SAW resonator, the second SAW resonator lacking a high velocity layer disposed within the dielectric material layer disposed on the IDT electrodes.

Abstract: Acoustic resonator devices and filters are disclosed. An acoustic resonator includes a piezoelectric plate having front and back surfaces and an interdigital transducer (IDT). The IDT has a first pitch/mark zone with interleaved fingers having a pitch equal to a first pitch value P1 and a mark equal to a first mark value M1, and a second pitch/mark zone with interleaved fingers having a pitch equal to a second pitch value P2 and a mark equal to a second mark value M2. A radio frequency signal applied to the IDT causes excitation of a same shear primary acoustic mode by both the first pitch/mark zone and the second pitch/mark zone. P1, M1, P2, and M2, are selected such that an amplitude of spurious modes is reduced as compared to a device having a same primary acoustic mode and a single pitch/mark zone.

Abstract: A first transmission line and a third transmission line are disposed at different positions in a thickness direction of a substrate. The third transmission line includes a first end portion connected to one end portion of the first transmission line, and a second end portion that is grounded. The first transmission line is electromagnetically coupled to the third transmission line. The first transmission line has a coil pattern and the third transmission line has a partially open loop pattern.

Abstract: Aspects of coaxial to microstrip transitional housings are described. In one example, a transitional housing includes a channel comprising sidewalls formed into the housing, and an opening formed at an end of the channel. The transitional housing also includes a plug that is fitted into the opening at an end of the channel. The plug has a flat surface positioned at the end of the channel, extending between the sidewalls of the channel, and an undercut below the flat surface. The transitional housing also includes a coaxial conductor aperture that extends from outside the housing, into the housing, into the plug, through the flat surface and undercut of the plug, and into the channel. Use of the plug offers a manufacturing solution for the mechanical and electrical transition between a coaxial feedthrough to a PCB microstrip secured within the housing. The solution helps to eliminate unwanted mismatches of the transition.