# US 12,119,804 B2 · Acoustic wave device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,119,804 B2 - Document ID: US12119804B2 - Status: Granted - Kind: B2 - Application number: 17/701,985 - Filed: 2022-03-23 - Published: 2022-07-07 - Granted: 2024-10-15 - Earliest claimed: 2019-09-27 - Assignees: Murata Manufacturing Co., Ltd. - Applicants: Murata Manufacturing Co., Ltd. - Inventors: Takashi Yamane; Sho Nagatomo; Tetsuya Kimura - Web page: https://patentgrep.com/patent/US12119804B2 ## CPC - H03H 9/02157: {Dimensional parameters, e.g. ratio between two dimension parameters, length, width or thickness} - 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 9/02015: {Characteristics of piezoelectric layers, e.g. cutting angles} - H03H 9/02102: {of temperature influence (cutting angles H03H9/02015)} - H03H 9/0211: {of reflections} - H03H 9/13: for networks consisting of piezoelectric or electrostrictive materials (for networks using surface acoustic waves H03H9/145) - H03H 9/132: {characterized by a particular shape} - H03H 9/174: {Membranes} - H03H 9/175: {Acoustic mirrors} - H03H 9/205: having multiple resonators (crystal tuning forks H03H9/21) - H03H 9/564: {implemented with thin-film techniques} - H03H 9/568: {consisting of a ladder configuration} - H03H: IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS (waveguides, resonators, lines or other devices of the waveguide type H01P) ## 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. ## Claims ### Claim 1 An acoustic wave device configured to use a thickness shear primary mode bulk wave, the acoustic wave device comprising: a piezoelectric layer; and a first electrode and a second electrode facing each other in a direction intersecting with a thickness direction of the piezoelectric layer; wherein a material of the piezoelectric layer is lithium niobate or lithium tantalate; multiple electrode portions including the first electrode and the second electrode are provided; a first divided resonator and a second divided resonator connected in series without another resonator being connected between the first divided resonator and the second divided resonator, or connected in parallel with each other to a same connection node on a path connecting an input terminal and an output terminal; a support substrate including a first main surface and a second main surface opposed to each other are provided; the first divided resonator includes a first electrode portion of the multiple electrode portions and a first installation portion of the piezoelectric layer including a first region in which the first electrode portion is provided; the second divided resonator includes a second electrode portion of the multiple electrode portions and a second installation portion of the piezoelectric layer including a second region in which the second electrode portion is provided; the piezoelectric layer is directly or indirectly provided on the support substrate; the support substrate includes: a first energy confinement layer at least partially overlapping with the first region of the piezoelectric layer in a plan view from the thickness direction of the piezoelectric layer; and a second energy confinement layer at least partially overlapping with the second region of the piezoelectric layer in a plan view from the thickness direction of the piezoelectric layer; and the first energy confinement layer and the second energy confinement layer are integrally provided with each other in the support substrate. ### Claim 2 (depends on 1) The acoustic wave device according to claim 1, wherein a thickness of the first divided resonator is a thickness of the first installation portion; a thickness of the second divided resonator is a thickness of the second installation portion; and the thickness of the first divided resonator and the thickness of the second divided resonator are different from each other. ### Claim 3 (depends on 1) The acoustic wave device according to claim 1, wherein a polarity of the first divided resonator and a polarity of the second divided resonator are different from each other. ### Claim 4 (depends on 1) The acoustic wave device according to claim 1, wherein the first energy confinement layer and the second energy confinement layer are acoustic reflection layers; the acoustic reflection layer includes: a high acoustic impedance layer; and a low acoustic impedance layer having an acoustic impedance lower than an acoustic impedance of the high acoustic impedance layer. ### Claim 5 (depends on 1) The acoustic wave device according to claim 1, wherein the first energy confinement layer and the second energy confinement layer include a cavity. ### Claim 6 (depends on 1) The acoustic wave device according to claim 1, wherein each of the first electrode and the second electrode is an electrode to have hot electric potential or ground electric potential. ### Claim 7 (depends on 1) The acoustic wave device according to claim 1, wherein the first energy confinement layer overlaps with the first electrode and the second electrode of the first electrode portion, and a portion of the piezoelectric layer between the first electrode and the second electrode of the first electrode portion, in a plan view from the thickness direction; and the second energy confinement layer overlaps with the first electrode and the second electrode of the second electrode portion, and a portion of the piezoelectric layer between the first electrode and the second electrode of the second electrode portion, in a plan view from the thickness direction. ### Claim 8 (depends on 1) The acoustic wave device according to claim 1, wherein the first electrode and the second electrode face each other on a same main surface of the piezoelectric layer. ### Claim 9 An acoustic wave device, comprising: a piezoelectric layer; and a first electrode and a second electrode facing each other in a direction intersecting with a thickness direction of the piezoelectric layer; wherein the first electrode and the second electrode are adjacent to each other; d/p is about 0.5 or less in any section along the thickness direction of the piezoelectric layer with a distance between center lines of the first electrode and the second electrode denoted as p, and a thickness of the piezoelectric layer denoted as d; a material of the piezoelectric layer is lithium niobate or lithium tantalate; multiple electrode portions including the first electrode and the second electrode are provided; a first divided resonator and a second divided resonator connected in series without another resonator being connected between the first divided resonator and the second divided resonator, or connected in parallel with each other to a same connection node on a path connecting an input terminal and an output terminal; a support substrate including a first main surface and a second main surface opposed to each other are provided; the first divided resonator includes a first electrode portion of the multiple electrode portions and a first installation portion of the piezoelectric layer including a first region in which the first electrode portion is provided; the second divided resonator includes a second electrode portion of the multiple electrode portions and a second installation portion of the piezoelectric layer including a second region in which the second electrode portion is provided; the piezoelectric layer is directly or indirectly provided on the support substrate; the support substrate includes: a first energy confinement layer at least partially overlapping with the first region of the piezoelectric layer in a plan view from the thickness direction of the piezoelectric layer; and a second energy confinement layer at least partially overlapping with the second region of the piezoelectric layer in a plan view from the thickness direction of the piezoelectric layer; and the first energy confinement layer and the second energy confinement layer are integrally provided with each other in the support substrate. ### Claim 10 (depends on 9) The acoustic wave device according to claim 9, wherein a thickness of the first divided resonator is a thickness of the first installation portion; a thickness of the second divided resonator is a thickness of the second installation portion; and the thickness of the first divided resonator and the thickness of the second divided resonator are different from each other. ### Claim 11 (depends on 9) The acoustic wave device according to claim 9, wherein a polarity of the first divided resonator and a polarity of the second divided resonator are different from each other. ### Claim 12 (depends on 9) The acoustic wave device according to claim 9, wherein the first energy confinement layer and the second energy confinement layer are acoustic reflection layers; the acoustic reflection layer includes: a high acoustic impedance layer; and a low acoustic impedance layer having an acoustic impedance lower than an acoustic impedance of the high acoustic impedance layer. ### Claim 13 (depends on 9) The acoustic wave device according to claim 9, wherein the first energy confinement layer and the second energy confinement layer include a cavity. ### Claim 14 (depends on 9) The acoustic wave device according to claim 9, wherein a distance between center lines in the first divided resonator and a distance between center lines in the second divided resonator are different from each other. ### Claim 15 (depends on 9) The acoustic wave device according to claim 9, wherein the d/p is about 0.24 or less. ### Claim 16 (depends on 15) The acoustic wave device according to claim 15, wherein the first electrode and the second electrode are adjacent to each other; the first electrode includes a first electrode main portion overlapping with the second electrode in a direction in which the first electrode and the second electrode face each other; the second electrode includes a second electrode main portion overlapping with the first electrode in the direction in which the first electrode and the second electrode face each other; the piezoelectric layer has a defined region in the piezoelectric layer that overlaps with both of the first electrode and the second electrode in the direction in which the first electrode and the second electrode face each other, and is positioned between the first electrode and the second electrode, in a plan view from a thickness direction of the piezoelectric layer; and in a plan view from a thickness direction of the piezoelectric layer; when an area of the first electrode main portion is denoted as S1; an area of the second electrode main portion is denoted as S2; an area of the defined region is denoted as S0; and a structural parameter defined by (S1+S2)/(S1+S2+S0) is denoted as MR; the acoustic wave device satisfies a condition MR≤1.75×(d/p)+0.075. ### Claim 17 (depends on 9) The acoustic wave device according to claim 9, wherein each of the first electrode and the second electrode is an electrode to have hot electric potential or ground electric potential. ### Claim 18 (depends on 9) The acoustic wave device according to claim 9, wherein the first energy confinement layer overlaps with the first electrode and the second electrode of the first electrode portion, and a portion of the piezoelectric layer between the first electrode and the second electrode of the first electrode portion, in a plan view from the thickness direction; and the second energy confinement layer overlaps with the first electrode and the second electrode of the second electrode portion, and a portion of the piezoelectric layer between the first electrode and the second electrode of the second electrode portion, in a plan view from the thickness direction. ### Claim 19 (depends on 9) The acoustic wave device according to claim 9, wherein the first electrode and the second electrode face each other on a same main surface of the piezoelectric layer.