Abstract: An acoustic resonator is provided that includes a substrate; a piezoelectric layer having a portion that forms a diaphragm over a cavity; and IDT on the piezoelectric layer that includes a first conductor level including first and second busbars disposed on respective portions of the piezoelectric layer, a first set of elongated fingers extending from the first bus bar onto the diaphragm, and a second set of elongated fingers extending from the second bus bar onto the diaphragm, the second set of elongated fingers interleaved with the first set of elongated fingers. The acoustic resonator also includes a second conductor level over the piezoelectric layer and covering at least portions of the first and second busbars.

Abstract: A radio frequency filter includes at least a first sub-filter and a second sub-filter connected in parallel between a first port and a second port. Each of the sub-filters has a piezoelectric plate having front and back surfaces, the back surface attached to a substrate, and portions of the piezoelectric plate forming diaphragms spanning respective cavities in the substrate. A conductor pattern is formed on the front surface of the plate, the conductor pattern includes interdigital transducers (IDTs) of a respective plurality of resonators, with interleaved fingers of each IDT disposed on a respective diaphragm of the plurality of diaphragms. A thickness of the portions of the piezoelectric plate of the first sub-filter is different from a thickness of the portions of the piezoelectric plate of the second sub-filter.

Abstract: An apparatus for filtering radio frequency signals is provided. The apparatus includes a substrate and a membrane coupled to the substrate that includes piezoelectric material. The apparatus also includes an interdigital transducer (IDT) coupled to the membrane and includes a plurality of interleaved fingers. The apparatus also includes a lid, in which the membrane is arranged between the substrate and the lid with a first cavity having a first height between the lid and a first main surface of the membrane and a second cavity having a second height between the substrate and a second main surface of the membrane that opposes the first main surface. Moreover, the first height between the lid and the first main surface of the membrane is greater than a pitch of at least one pair of interleaved fingers of the plurality of interleaved fingers and at most four times greater than the second height.

Abstract: An acoustic resonator device with low thermal impedance has a substrate and a single-crystal piezoelectric plate having a back surface attached to a top surface of the substrate via a bonding oxide (BOX) layer. An interdigital transducer (IDT) formed on the front surface of the plate has interleaved fingers disposed on the diaphragm. The piezoelectric plate and the BOX layer are removed from a least a portion of the surface area of the device to provide lower thermal resistance between the conductor pattern and the substrate.

Abstract: Acoustic resonators are disclosed. An acoustic resonator includes a substrate having a surface and a single-crystal piezoelectric plate having front and back surfaces. The back surface is attached to the surface of the substrate except for a portion of the piezoelectric plate forming a diaphragm spanning a cavity in the substrate. An interdigital transducer (IDT) is formed on the front surface of the piezoelectric plate. The IDT includes: a first busbar and a second busbar disposed on respective portions of the piezoelectric plate other than the diaphragm; a first set of elongate fingers extending from the first bus bar onto the diaphragm; and a second set of elongate fingers extending from the second bus bar onto the diaphragm, the second set of elongate fingers interleaved with the first set of elongate fingers.

Abstract: An acoustic resonator device with low thermal impedance has a substrate and a single-crystal piezoelectric plate having a back surface attached to a top surface of the substrate via a bonding oxide (BOX) layer. An interdigital transducer (IDT) formed on the front surface of the plate has interleaved fingers disposed on the diaphragm. The piezoelectric plate and the BOX layer are removed from a least a portion of the surface area of the device to provide lower thermal resistance between the IDT and the substrate.

Abstract: An acoustic resonator is provided that includes a substrate; a piezoelectric layer supported by the substrate; and an interdigital transducer (IDT) at a surface of the piezoelectric layer. The IDT includes a pair of busbars and a plurality of electrode fingers extending from the first and second busbars to be interleaved with each other. The respective widths of at least a portion of the electrode fingers increases in a direction from respective first ends of the first and second busbars to the respective second end of the first and second busbars. Moreover, a pitch of the portion of the electrode fingers decreases in the direction from the respective first ends of the first and second busbar to the respective second ends of the first and second busbars.

Abstract: A radio frequency filter includes at least a first sub-filter and a second sub-filter connected in parallel between a first port and a second port. Each of the sub-filters has a piezoelectric plate having front and back surfaces, the back surface attached to a substrate, and portions of the piezoelectric plate forming diaphragms spanning respective cavities in the substrate. A conductor pattern is formed on the front surface of the plate, the conductor pattern includes interdigital transducers (IDTs) of a respective plurality of resonators, with interleaved fingers of each IDT disposed on a respective diaphragm of the plurality of diaphragms. A thickness of the portions of the piezoelectric plate of the first sub-filter is different from a thickness of the portions of the piezoelectric plate of the second sub-filter.

Abstract: A filter device is provided that includes a substrate having a surface and a piezoelectric plate supported by the substrate. A plurality of interdigital transducers (IDTs) for multiple resonators are provided that each have interleaved fingers at respective diaphragms of the piezoelectric plate disposed over one or more cavities. Moreover, a first resonator includes a first plurality of interleaved fingers having a first pitch and a second resonator includes a second plurality of interleaved fingers having a second pitch that is different than the first pitch. This configuration adjusts the resonance frequencies of each resonator. Moreover, a dielectric layer may be uniformly disposed over at least one surface of the respective diaphragms of the piezoelectric plate.

Abstract: A radio frequency filter includes at least a first sub-filter and a second sub-filter connected in parallel between a first port and a second port. Each of the sub-filters has a piezoelectric plate having front and back surfaces, the back surface attached to a substrate, and portions of the piezoelectric plate forming diaphragms spanning respective cavities in the substrate. A conductor pattern is formed on the front surface of the plate, the conductor pattern includes interdigital transducers (IDTs) of a respective plurality of resonators, with interleaved fingers of each IDT disposed on a respective diaphragm of the plurality of diaphragms. A thickness of the portions of the piezoelectric plate of the first sub-filter is different from a thickness of the portions of the piezoelectric plate of the second sub-filter.

Abstract: A filter may include a substrate and a rotated YX-cut piezoelectric plate coupled to the substrate. The filter also may include an interdigital transducer (IDT) formed on a portion of the rotated YX-cut piezoelectric plate forming a diaphragm that spans a cavity between the rotated YX-cut piezoelectric plate and the substrate. The IDT includes interleaved fingers that are disposed on the diaphragm. The IDT has an aperture that is less than or equal to 4 times a pitch of the interleaved fingers.

Abstract: An acoustic resonator has a piezoelectric plate having first and second surfaces, the second surface facing a substrate, and a diaphragm of the piezoelectric plate spanning a cavity. A conductor pattern is formed on at least one of the first and second surfaces and has an interdigital transducer (IDT) having interleaved fingers on the diaphragm portion of the piezoelectric plate. At least one of a pitch of the interleaved IDT fingers or a mark of the interleaved IDT fingers varies over an area of the IDT to compensate for process-induced distortion of the diaphragm portion of the piezoelectric plate.

Abstract: Acoustic resonator devices are disclosed. An acoustic resonator device includes a plurality of cells electrically connected in parallel. Each cell includes an interdigital transducer (IDT) on a piezoelectric plate, the IDT having at least 15 and not more than 35 interleaved fingers.

Abstract: An acoustic resonator has a substrate having a surface and a single-crystal piezoelectric plate, with a portion of the piezoelectric plate forming a diaphragm that spans a cavity in the substrate. An interdigital transducer (IDT) is formed on a surface of the single-crystal piezoelectric plate such that interleaved fingers of the IDT are disposed on the diaphragm. The ends of IDT interleaved fingers or inner surfaces of the opposing busbars have a curved shape. In some cases, gaps between ends of the interleaved fingers and opposing busbars have one of circular gap shapes or parabolic gap shapes. The cavity may be formed in an intermediate layer of the substrate.

Abstract: An acoustic resonator device includes a diaphragm a diaphragm comprising a portion of a piezoelectric plate spanning a cavity. A conductor pattern on a surface of the piezoelectric plate includes an interdigital transducer (IDT) with a first busbar, a second busbar, and a plurality of interleaved IDT fingers extending alternately from the first and second busbars. Overlapping portions of the plurality of interleaved fingers are on the diaphragm. The conductor pattern also includes a first reflector element on the diaphragm proximate and parallel to a first IDT finger, and a second reflector element on the diaphragm proximate and parallel to a last IDT finger. A center-to-center spacing of the first reflector element and the first IDT finger and the second reflector element and the last IDT finger is greater than an average center-to-center spacing between all adjacent pairs of IDT fingers.

Abstract: Acoustic resonator devices and acoustic filter devices. An acoustic resonator includes a piezoelectric plate having front and back surfaces. The back surface is attached to a surface of 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 multi-pitch interdigital transducer (IDT), wherein fingers of the IDT are on the diaphragm.

Abstract: A radio frequency filter includes at least a first sub-filter and a second sub-filter connected in parallel between a first port and a second port. Each of the sub-filters has a piezoelectric plate having front and back surfaces, the back surface attached to a substrate, and portions of the piezoelectric plate forming diaphragms spanning respective cavities in the substrate. A conductor pattern is formed on the front surface of the plate, the conductor pattern includes interdigital transducers (IDTs) of a respective plurality of resonators, with interleaved fingers of each IDT disposed on a respective diaphragm of the plurality of diaphragms. A thickness of the portions of the piezoelectric plate of the first sub-filter is different from a thickness of the portions of the piezoelectric plate of the second sub-filter.

Abstract: A radio frequency filter includes at least a first sub-filter and a second sub-filter connected in parallel between a first port and a second port. Each of the sub-filters has a piezoelectric plate having front and back surfaces, the back surface attached to a substrate, and portions of the piezoelectric plate forming diaphragms spanning respective cavities in the substrate. A conductor pattern is formed on the front surface of the plate, the conductor pattern includes interdigital transducers (IDTs) of a respective plurality of resonators, with interleaved fingers of each IDT disposed on a respective diaphragm of the plurality of diaphragms. A thickness of the portions of the piezoelectric plate of the first sub-filter is different from a thickness of the portions of the piezoelectric plate of the second sub-filter.

Abstract: An acoustic resonator device with low thermal impedance has a substrate and a single-crystal piezoelectric plate having a back surface attached to a top surface of the substrate via a bonding oxide (BOX) layer. An interdigital transducer (IDT) formed on the front surface of the plate has interleaved fingers disposed on the diaphragm, the overlapping distance of the interleaved fingers defining an aperture of the resonator device. Contact pads are formed at selected locations over the surface of the substrate to provide electrical connections between the IDT and contact bumps to be attached to the contact pads. The piezoelectric plate is removed from at least a portion of the surface area of the device beneath each of the contact pads to provide lower thermal resistance between the contact bumps and the substrate.

Abstract: An acoustic resonator device with low thermal impedance has a substrate and a single-crystal piezoelectric plate having a back surface attached to a top surface of the substrate via a bonding oxide (BOX) layer. An interdigital transducer (IDT) formed on the front surface of the plate has interleaved fingers disposed on the diaphragm, the overlapping distance of the interleaved fingers defining an aperture of the resonator device. Contact pads are formed at selected locations over the surface of the substrate to provide electrical connections between the IDT and contact bumps to be attached to the contact pads. The piezoelectric plate is removed from at least a portion of the surface area of the device beneath each of the contact pads to provide lower thermal resistance between the contact bumps and the substrate.