Patents by Inventor Seiji Kai

Seiji Kai has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11245380
    Abstract: In an acoustic wave device, a piezoelectric body is directly or indirectly laminated on a silicon support substrate, and a functional electrode is provided on the piezoelectric body. A support layer is directly or indirectly laminated on the silicon support substrate, and the support layer is located outside the functional electrode when viewed in plan view. A silicon cover layer is provided on the support layer that includes an insulating material, and a space A is defined by the silicon support substrate, the support layer, and the silicon cover layer. The electric resistance of the silicon support substrate is higher than the electric resistance of the silicon cover layer.
    Type: Grant
    Filed: June 19, 2020
    Date of Patent: February 8, 2022
    Assignee: MURATA MANUFACTURING CO., LTD.
    Inventors: Makoto Sawamura, Seiji Kai, Yutaka Kishimoto, Yuzo Kishi
  • Patent number: 10958240
    Abstract: An elastic wave device includes a multilayer film stacked on a support substrate. A first support layer surrounds a region including interdigital transducer electrodes. A second support layer is disposed in the region surrounded by the first support layer. A cover is fixed on the first support layer and the second support layer so as to close a cavity defined by the first support layer. The multilayer film is partially disposed on the support substrate, and an insulating layer is disposed in at least a portion of a region in which the multilayer film is not disposed. At least one of the first support layer and the second support layer is disposed on the insulating layer.
    Type: Grant
    Filed: December 5, 2017
    Date of Patent: March 23, 2021
    Assignee: MURATA MANUFACTURING CO., LTD.
    Inventors: Masahiro Fukushima, Seiji Kai, Takuya Koyanagi
  • Patent number: 10862455
    Abstract: An elastic wave device includes a piezoelectric thin film provided on a low acoustic velocity film and an IDT electrode provided on the piezoelectric thin film, wherein the piezoelectric thin film is made of a piezoelectric single crystal and includes a first principal surface that is a positive surface in a polarization axis direction and a second principal surface that is a negative surface in the polarization axis direction. The first principal surface of the piezoelectric thin film faces the low acoustic velocity film, and the second principal surface faces the IDT electrode.
    Type: Grant
    Filed: December 7, 2017
    Date of Patent: December 8, 2020
    Assignee: MURATA MANUFACTURING CO., LTD.
    Inventors: Tsutomu Takai, Atsushi Tanaka, Seiji Kai
  • Publication number: 20200321938
    Abstract: In an acoustic wave device, a piezoelectric body is directly or indirectly laminated on a silicon support substrate, and a functional electrode is provided on the piezoelectric body. A support layer is directly or indirectly laminated on the silicon support substrate, and the support layer is located outside the functional electrode when viewed in plan view. A silicon cover layer is provided on the support layer that includes an insulating material, and a space A is defined by the silicon support substrate, the support layer, and the silicon cover layer. The electric resistance of the silicon support substrate is higher than the electric resistance of the silicon cover layer.
    Type: Application
    Filed: June 19, 2020
    Publication date: October 8, 2020
    Inventors: Makoto SAWAMURA, Seiji KAI, Yutaka KISHIMOTO, Yuzo KISHI
  • Publication number: 20200321937
    Abstract: An acoustic wave device includes a silicon support substrate that includes first and second main surfaces opposing each other, a piezoelectric structure provided on the first main surface and including the piezoelectric layer, an IDT electrode provided on the piezoelectric layer, a support layer provided on the first main surface of the silicon support substrate and surrounding the piezoelectric layer, a cover layer provided on the support layer, a through-via electrode that extending through the silicon support substrate and the piezoelectric structure, and a first wiring electrode connected to the through-via electrode and electrically connected to the IDT electrode. The piezoelectric structure includes at least one layer having an insulating property, the at least one layer including the piezoelectric layer. The first wiring electrode is provided on the layer having an insulating property in the piezoelectric structure.
    Type: Application
    Filed: June 19, 2020
    Publication date: October 8, 2020
    Inventors: Yuzo KISHI, Yutaka KISHIMOTO, Makoto SAWAMURA, Seiji KAI
  • Publication number: 20200321933
    Abstract: An acoustic wave device includes a piezoelectric substrate including a support substrate and a piezoelectric layer on the support substrate, the piezoelectric substrate including a first principal surface on the piezoelectric layer side, and a second principal surface on the support substrate side, an IDT electrode on the first principal surface, a support layer on the support substrate, a cover on the support layer, a through-via electrode provided through the support substrate and electrically connected to the IDT electrode, a first wiring electrode on the second principal surface of the piezoelectric substrate and electrically connected to the through-via electrode, and a protective film on the second principal surface to cover at least a portion of the first wiring electrode. The protective film is provided on an inner side of the support layer when viewed in a direction normal or substantially normal to the second principal surface.
    Type: Application
    Filed: June 19, 2020
    Publication date: October 8, 2020
    Inventors: Yutaka KISHIMOTO, Seiji KAI, Makoto SAWAMURA, Yuzo KISHI
  • Patent number: 10707830
    Abstract: An elastic wave device includes a piezoelectric substrate, functional electrodes on the piezoelectric substrate, a support layer on the piezoelectric substrate with a frame shape surrounding the functional electrodes, a cover member on the support layer to seal an opening of the support layer, the cover member including a first main surface facing the support layer, and a second main surface opposite to the first main surface. Recesses are located in the cover member and are open to the second main surface. Via holes extend through the support layer and to bottom surfaces of the recesses of the cover member, the via holes each including an opening that is open to the bottom surface. The area of the opening of each of the via holes is not more than the area of the bottom surface of the corresponding recess of the cover member. First via conductor portions are provided in the via holes and second via conductor portions are provided in the recesses of the cover member.
    Type: Grant
    Filed: December 13, 2016
    Date of Patent: July 7, 2020
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Taku Kikuchi, Seiji Kai, Motoji Tsuda, Mitsuyoshi Hira
  • Patent number: 10659002
    Abstract: An elastic wave device includes a lamination layer film including a piezoelectric thin film on a support substrate. The lamination layer film is not partially present in a region located in an outer side portion of a region where IDT electrodes are provided. A first insulation layer extends from at least a portion of a region where the lamination layer film is not present to an upper portion of the piezoelectric thin film. A wiring electrode has a width of about 6 ?m and extends from the upper portion of the piezoelectric thin film to an upper portion of the first insulation layer, and extends onto a section of the first insulation layer in the region.
    Type: Grant
    Filed: August 22, 2018
    Date of Patent: May 19, 2020
    Assignee: MURATA MANUFACTURING CO., LTD.
    Inventors: Koji Yamamoto, Tsutomu Takai, Seiji Kai, Hisashi Yamazaki, Yuji Miwa, Takashi Yamane, Noriyoshi Ota, Atsushi Tanaka
  • Patent number: 10659001
    Abstract: An elastic wave device includes a lamination layer film including a piezoelectric thin film on a support substrate. The lamination layer film is not partially present in a region located in an outer side portion of a region where IDT electrodes are provided. A first insulation layer extends from at least a portion of a region where the lamination layer film is not present to an upper portion of the piezoelectric thin film. A wiring electrode extends from the upper portion of the piezoelectric thin film to an upper portion of the first insulation layer, and extends onto a section of the first insulation layer in the region.
    Type: Grant
    Filed: December 5, 2017
    Date of Patent: May 19, 2020
    Assignee: MURATA MANUFACTURING CO., LTD.
    Inventors: Koji Yamamoto, Tsutomu Takai, Seiji Kai, Hisashi Yamazaki, Yuji Miwa, Takashi Yamane
  • Patent number: 10644669
    Abstract: Functional element units and a connection line electrically connecting the functional element units are formed on one principal surface of a piezoelectric motherboard. A resin support layer enclosing the functional element units is formed on the one principal surface of the motherboard. An elastic wave device with the functional units is obtained by dividing a multilayer body including the motherboard, the functional element units, and the support layer into a plurality of sections along a dicing line. The connection line includes a line main body positioned on the dicing line, and a connection unit in which the line main body and the functional element units are electrically connected. Prior to dividing the multilayer body, a retaining member made of resin which straddles the line main body in the width direction of the line main body is formed separate from the support layer on the motherboard.
    Type: Grant
    Filed: May 1, 2019
    Date of Patent: May 5, 2020
    Assignee: MURATA MANUFACTURING CO., LTD.
    Inventors: Mitsuyoshi Hira, Seiji Kai
  • Patent number: 10637432
    Abstract: An elastic wave device includes a support substrate, a film stack including a piezoelectric thin film, and an IDT electrode. The film stack is partially absent in a region outside a region where the IDT electrode is located in plan view. The elastic wave device further includes a support layer located on the support substrate in at least a portion of a region where the film stack is partially absent and surrounds a region where the film stack is located in plan view and a cover member located on the support layer. The cover member defines a hollow space facing the IDT electrode together with the piezoelectric thin film and the support layer.
    Type: Grant
    Filed: November 29, 2017
    Date of Patent: April 28, 2020
    Assignee: MURATA MANUFACTURING CO., LTD.
    Inventor: Seiji Kai
  • Patent number: 10622965
    Abstract: A surface acoustic wave device assembly includes a collective board, first circuit portions provided on the collective board and respectively including first hot terminals and first ground terminals, a second circuit portion provided on the collective board and including second hot terminals and second ground terminals, and a power supply wiring provided on the collective board so as to surround the periphery of the first circuit portions and the second circuit portion. The first circuit portions include surface acoustic wave devices defining band pass filters. The second circuit portion defines a band pass filter. The first ground terminals and first hot terminals, and the second ground terminal are connected to the power supply wiring, the second hot terminals are not connected to the power supply wiring, and pass bands of the surface acoustic wave devices and a pass band of the band pass filter defined by the second circuit portion are the same or substantially the same.
    Type: Grant
    Filed: July 17, 2017
    Date of Patent: April 14, 2020
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Toru Takeshita, Seiji Kai, Takashi Naka, Motoji Tsuda, Mitsuyoshi Hira
  • Publication number: 20190312559
    Abstract: An elastic wave device manufacturing method includes a preparing a piezoelectric wafer on which IDT electrodes are provided in elastic wave device forming portions, providing on a first main surface of the piezoelectric wafer support layers in the elastic wave device forming portions, bonding a cover member to cover the support layers to obtain a multilayer body, cutting the multilayer body in a first direction multiple times, cutting the multilayer body in a second direction orthogonal to the first direction to obtain elastic wave devices, in which a resin layer extends across a boundary between the elastic wave device forming portions adjacent to each other on the first main surface of the piezoelectric wafer, and the second cutting step is performed in a state in which the resin layer is present.
    Type: Application
    Filed: June 20, 2019
    Publication date: October 10, 2019
    Inventors: Makoto SAWAMURA, Seiji KAI
  • Publication number: 20190260341
    Abstract: Functional element units and a connection line electrically connecting the functional element units are formed on one principal surface of a piezoelectric motherboard. A resin support layer enclosing the functional element units is formed on the one principal surface of the motherboard. An elastic wave device with the functional units is obtained by dividing a multilayer body including the motherboard, the functional element units, and the support layer into a plurality of sections along a dicing line. The connection line includes a line main body positioned on the dicing line, and a connection unit in which the line main body and the functional element units are electrically connected. Prior to dividing the multilayer body, a retaining member made of resin which straddles the line main body in the width direction of the line main body is formed separate from the support layer on the motherboard.
    Type: Application
    Filed: May 1, 2019
    Publication date: August 22, 2019
    Inventors: Mitsuyoshi HIRA, Seiji KAI
  • Patent number: 10374142
    Abstract: In a surface acoustic wave device, a conductor pattern is located on a main surface of a piezoelectric substrate and includes a surface acoustic wave element pattern, a pad and a feed line that is electrically connected to the pad and extends up to an outer peripheral edge of the main surface. The piezoelectric substrate and a cover are bonded to each other with a support layer therebetween that includes a frame extending along the outer peripheral edge of the main surface so that a gap is provided between the frame and the outer peripheral edge and includes a pad adjacent portion on the pad. Thus, a closed space is surrounded by the piezoelectric substrate, the cover and the frame. The support layer further includes a reinforcement portion that intersects a feed line at or near an intersection portion in which a separated portion of the frame that is separated from the pad adjacent portion intersects the feed line.
    Type: Grant
    Filed: February 11, 2016
    Date of Patent: August 6, 2019
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Daisuke Ajima, Seiji Kai
  • Patent number: 10320355
    Abstract: Functional element units and a connection line electrically connecting the functional element units are formed on one principal surface of a piezoelectric motherboard. A resin support layer enclosing the functional element units is formed on the one principal surface of the motherboard. An elastic wave device with the functional units is obtained by dividing a multilayer body including the motherboard, the functional element units, and the support layer into a plurality of sections along a dicing line. The connection line includes a line main body positioned on the dicing line, and a connection unit in which the line main body and the functional element units are electrically connected. Prior to dividing the multilayer body, a retaining member made of resin which straddles the line main body in the width direction of the line main body is formed separate from the support layer on the motherboard.
    Type: Grant
    Filed: May 6, 2015
    Date of Patent: June 11, 2019
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Mitsuyoshi Hira, Seiji Kai
  • Patent number: 10243536
    Abstract: In an elastic wave device, a multilayer film including a piezoelectric thin film is provided on a support substrate, an interdigital transducer electrode is provided on one surface of the piezoelectric thin film, a wiring electrode is connected to the interdigital transducer electrode, the wiring electrode includes a lead electrode portion and a pad electrode portion, an external connection terminal is located above the pad electrode portion, the external connection terminal is electrically connected to the pad electrode portion, and the external connection terminal is bonded onto the pad electrode portion on the support substrate so that at least the piezoelectric thin film of the multilayer film is not present below the pad electrode portion.
    Type: Grant
    Filed: June 13, 2016
    Date of Patent: March 26, 2019
    Assignee: MURATA MANUFACTURING CO., LTD.
    Inventors: Shin Saijo, Hisashi Yamazaki, Koji Yamamoto, Seiji Kai, Munehisa Watanabe
  • Publication number: 20180358950
    Abstract: An elastic wave device includes a lamination layer film including a piezoelectric thin film on a support substrate. The lamination layer film is not partially present in a region located in an outer side portion of a region where IDT electrodes are provided. A first insulation layer extends from at least a portion of a region where the lamination layer film is not present to an upper portion of the piezoelectric thin film. A wiring electrode has a width of about 6 ?m and extends from the upper portion of the piezoelectric thin film to an upper portion of the first insulation layer, and extends onto a section of the first insulation layer in the region.
    Type: Application
    Filed: August 22, 2018
    Publication date: December 13, 2018
    Inventors: Koji YAMAMOTO, Tsutomu TAKAI, Seiji KAI, Hisashi YAMAZAKI, Yuji MIWA, Takashi YAMANE, Noriyoshi OTA, Atsushi TANAKA
  • Patent number: 10148245
    Abstract: An elastic wave device includes a support substrate and a laminated film disposed on the support substrate. A portion of the laminated film is removed in a region outside a region in which an interdigital transducer electrode is disposed and below a region to which an external connection terminal is joined. An insulating layer is disposed in at least a portion of the region in which the portion of the laminated film is removed. A support layer is disposed on the insulating layer so as to surround the region in which the interdigital transducer electrode is disposed. A main component of a material of which the support layer is made is about 50% or more identical to a main component of a material of which the insulating layer is made. A cover is secured to the support layer to seal a cavity defined by the support layer.
    Type: Grant
    Filed: June 9, 2016
    Date of Patent: December 4, 2018
    Assignee: MURATA MANUFACTURING CO., LTD.
    Inventor: Seiji Kai
  • Publication number: 20180102761
    Abstract: An elastic wave device includes a piezoelectric thin film provided on a low acoustic velocity film and an IDT electrode provided on the piezoelectric thin film, wherein the piezoelectric thin film is made of a piezoelectric single crystal and includes a first principal surface that is a positive surface in a polarization axis direction and a second principal surface that is a negative surface in the polarization axis direction. The first principal surface of the piezoelectric thin film faces the low acoustic velocity film, and the second principal surface faces the IDT electrode.
    Type: Application
    Filed: December 7, 2017
    Publication date: April 12, 2018
    Inventors: Tsutomu TAKAI, Atsushi TANAKA, Seiji KAI