# US 12,119,798 B2 · Transversely-excited film bulk acoustic resonator package and method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,119,798 B2 - Document ID: US12119798B2 - Status: Granted - Kind: B2 - Application number: 18/153,741 - Filed: 2023-01-12 - Published: 2023-06-01 - Granted: 2024-10-15 - Earliest claimed: 2019-04-05 - Assignees: Murata Manufacturing Co., Ltd. - Applicants: Murata Manufacturing Co., Ltd. - Inventors: Patrick Turner; Mike Eddy; Andrew Kay; Ventsislav Yantchev; Charles Chung - Web page: https://patentgrep.com/patent/US12119798B2 ## CPC - H03H 3/02: for the manufacture of piezoelectric or electrostrictive resonators or networks (H03H3/08 takes precedence) - H03H 3/04: for obtaining desired frequency or temperature coefficient - H03H 9/02228: {Guided bulk acoustic wave devices or Lamb wave devices having interdigital transducers situated in parallel planes on either side of a piezoelectric layer} - H03H 9/02992: {Details of bus bars, contact pads or other electrical connections for finger electrodes} - H03H 9/0523: {for flip-chip mounting} - H03H 9/1035: {the enclosure being defined by two sealing substrates sandwiching the piezoelectric layer of the BAW device} - H03H 9/1042: {the enclosure being defined by a housing formed by a cavity in a resin} - H03H 9/105: {the enclosure being defined by a cover cap mounted on an element forming part of the BAW device} - H03H 9/1085: {the enclosure being defined by a non-uniform sealing mass covering the non-active sides of the SAW device} - H03H 9/25: Constructional features of resonators using surface acoustic waves {(devices for manipulating acoustic surface waves in general G10K11/36)} - H03H 9/586: {Means for mounting to a substrate, i.e. means constituting the material interface confining the waves to a volume} - H03H 9/6406: {Filters characterised by a particular frequency characteristic} - H03H 9/0514: {consisting of mounting pads or bumps} - H03H 2003/021: {the resonators or networks being of the air-gap type} - H03H 2003/023: {the resonators or networks being of the membrane type} - H03H: IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS (waveguides, resonators, lines or other devices of the waveguide type H01P) ## Abstract Acoustic resonator devices and filters are disclosed. A piezoelectric plate is attached to a substrate, a portion of the piezoelectric plate forming a diaphragm spanning a cavity in the substrate. A first conductor pattern is formed on a surface of the piezoelectric plate. The first conductor pattern includes interleaved fingers of an interdigital transducer disposed on the diaphragm, and a first plurality of contact pads. A second conductor pattern is formed on a surface of a base, the second conductor pattern including a second plurality of contact pads. Each pad of the first plurality of contact pads is connected to a respective pad of the second plurality of contact pads. A seal is formed between a perimeter of the piezoelectric plate and a perimeter of the base. ## Claims ### Claim 1 An acoustic resonator device comprising: an acoustic resonator chip comprising: a substrate; a piezoelectric layer having first and second opposing surfaces and that is above a surface of the substrate, such that a portion of the piezoelectric layer forms a diaphragm spanning a cavity between the piezoelectric layer and the substrate; and a first conductor pattern on at least one of the first and second surfaces of the piezoelectric layer, the first conductor pattern comprising an interdigitated transducer (IDT) having interleaved fingers on the diaphragm and a first contact pad; and an interposer having a planar surface facing the piezoelectric layer and a second conductor pattern with a second contact pad on the planar surface of the interposer, wherein at least a portion of the first conductor pattern is bonded to at least a portion of the second conductor pattern to form a seal that couples a perimeter of the piezoelectric layer of the acoustic resonator chip to a perimeter of the interposer. ### Claim 2 (depends on 1) The acoustic resonator device according to claim 1, wherein the first and second opposing surfaces of the piezoelectric layer are front and back surfaces, respectively, and the first conductor pattern is on the front surface of the piezoelectric layer. ### Claim 3 (depends on 1) The acoustic resonator device according to claim 1, further comprising a cap bonded to a back surface of the substrate. ### Claim 4 (depends on 1) The acoustic resonator device according to claim 1, wherein the seal is a hermetic seal that couples the piezoelectric layer to the interposer. ### Claim 5 (depends on 1) The acoustic resonator device according to claim 1, wherein the first conductor pattern further comprises a first metal, the second conductor pattern further comprises a second metal, and the seal is the first metal directly bonded to the second metal. ### Claim 6 (depends on 1) The acoustic resonator device according to claim 1, wherein the interposer is a printed circuit board that comprises a plurality of vias that connect the second contact pad to a third contact pad on a surface of the interposer opposite the planar surface of the interposer that faces the piezoelectric layer. ### Claim 7 (depends on 1) The acoustic resonator device according to claim 1, wherein the interposer further comprises a recess that faces the diaphragm. ### Claim 8 An acoustic resonator device comprising: a radio frequency filter comprising: a substrate; a piezoelectric layer attached to the substrate either directly or via one or more intermediate layers; and a first conductor pattern on the piezoelectric layer and including an interdigitated transducer (IDT) with interleaved fingers and a first contact pad on the piezoelectric layer opposite the substrate; and an interposer having a planar surface facing the piezoelectric layer and a second conductor pattern with a second contact pad on the planar surface of the interposer that faces the piezoelectric layer, wherein the first conductor pattern is bonded to the second conductor pattern to form a seal to prevent an intrusion of fluids to an interior of the radio frequency filter, and wherein the seal couples a perimeter of the piezoelectric layer to a perimeter of the interposer. ### Claim 9 (depends on 8) The acoustic resonator device according to claim 8, wherein the piezoelectric layer comprises front and back surfaces, respectively, and the first conductor pattern is on the front surface of the piezoelectric layer. ### Claim 10 (depends on 8) The acoustic resonator device according to claim 8, further comprising a cap bonded to a back surface of the substrate. ### Claim 11 (depends on 8) The acoustic resonator device according to claim 8, wherein the first conductor pattern further comprises a first metal, the second conductor pattern further comprises a second metal, and the seal is the first metal directly bonded to the second metal. ### Claim 12 (depends on 8) The acoustic resonator device according to claim 8, wherein the interposer is a printed circuit board that comprises a plurality of vias that connect the second contact pad to a third contact pad on a surface of the interposer opposite the planar surface of the interposer that faces the piezoelectric layer. ### Claim 13 (depends on 8) The acoustic resonator device according to claim 8, wherein the interposer further comprises a recess that faces the diaphragm. ### Claim 14 An acoustic resonator device comprising: a substrate; a piezoelectric layer above the substrate and including a diaphragm that is suspended over a cavity between the piezoelectric layer and the substrate; a first conductor pattern on the piezoelectric layer and including an interdigitated transducer (IDT) with interleaved fingers on the diaphragm and a first contact pad; an interposer having a planar surface facing the piezoelectric layer and a second conductor pattern with a second contact pad on the planar surface of the interposer that face the piezoelectric layer; and a metal seal formed by the first conductor pattern being bonded to the second conductor pattern and that couples the acoustic resonator chip to the interposer, wherein the interposer is a printed circuit board that comprises a plurality of vias that connect the second contact pad to a third contact pad on a surface of the interposer opposite the planar surface of the interposer that faces the piezoelectric layer. ### Claim 15 (depends on 14) The acoustic resonator device according to claim 14, wherein the piezoelectric layer comprises front and back surfaces, respectively, and the first conductor pattern is on the front surface of the piezoelectric layer. ### Claim 16 (depends on 14) The acoustic resonator device according to claim 14, wherein the metal seal is a hermetic continuous metal seal that couples a perimeter of the piezoelectric layer to a perimeter of the interposer. ### Claim 17 (depends on 14) The acoustic resonator device according to claim 14, wherein the first conductor pattern further comprises a first metal, the second conductor pattern further comprises a second metal, and the metal seal is the first conductor bonded to the second conductor. ### Claim 18 (depends on 14) The acoustic resonator device according to claim 14, wherein the interposer further comprises a recess that faces the diaphragm.