Patents by Inventor Takayuki Naba

Takayuki Naba 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: 11948900
    Abstract: A bonded body according to an embodiment includes a substrate, a metal member, and a bonding layer. The bonding layer is provided between the substrate and the metal member. The bonding layer includes a first particle including carbon, a first region including a metal, and a second region including titanium. The second region is provided between the first particle and the first region. A concentration of titanium in the second region is greater than a concentration of titanium in the first region.
    Type: Grant
    Filed: September 2, 2021
    Date of Patent: April 2, 2024
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA MATERIALS CO., LTD.
    Inventors: Maki Yonetsu, Seiichi Suenaga, Sachiko Fujisawa, Takayuki Naba
  • Publication number: 20230380060
    Abstract: A ceramic circuit board includes a ceramic substrate and a metal plate bonded together via a bonding layer, wherein when the ceramic circuit board is observed through a cross-section defined by a thickness direction and lateral direction of the ceramic circuit board: a side surface of the metal plate has an inclined shape; and the bonding layer has a bonding-layer protruding portion which protrudes by 20 ?m or more and 150 ?m or less from an edge where the bonding layer is in contact with the side surface of the metal plate. The shape and Vickers hardness of the side surface of the metal plate are controlled. The ceramic substrate is preferably a silicon nitride substrate.
    Type: Application
    Filed: August 3, 2023
    Publication date: November 23, 2023
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA MATERIALS CO., LTD.
    Inventors: Takayuki NABA, Keiichi YANO, Hiromasa KATO
  • Publication number: 20230154826
    Abstract: According to one embodiment, a ceramic metal circuit board is a ceramic metal circuit board formed by bonding metal circuit plates to at least one surface of a ceramic substrate. At least one of the metal circuit plates has an area of not less than 100 mm2 and includes a concave portion having a depth of not less than 0.02 mm within a range of 1% to 70% of a surface of the at least one of the metal circuit plates. The concave portion is provided not less than 3 mm inside from an end of the metal circuit plate.
    Type: Application
    Filed: January 19, 2023
    Publication date: May 18, 2023
    Inventors: Takayuki NABA, Keiichi YANO, Hiromasa KATO
  • Patent number: 11594467
    Abstract: According to one embodiment, a ceramic metal circuit board is a ceramic metal circuit board formed by bonding metal circuit plates to at least one surface of a ceramic substrate. At least one of the metal circuit plates has an area of not less than 100 mm2 and includes a concave portion having a depth of not less than 0.02 mm within a range of 1% to 70% of a surface of the at least one of the metal circuit plates. The concave portion is provided not less than 3 mm inside from an end of the metal circuit plate.
    Type: Grant
    Filed: August 21, 2019
    Date of Patent: February 28, 2023
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA MATERIALS CO., LTD.
    Inventors: Takayuki Naba, Keiichi Yano, Hiromasa Kato
  • Publication number: 20220037225
    Abstract: A ceramic copper circuit board including a ceramic substrate, and a copper circuit part located on the ceramic substrate, wherein an arbitrary line parallel to a first direction at a cross section of the copper circuit part parallel to the first direction crosses multiple copper crystal grains, the first direction is from the ceramic substrate toward the copper circuit part, an average of multiple distances in a second direction between the line and edges of the copper crystal grains is not more than 300 ?m, and the second direction is perpendicular to the first direction.
    Type: Application
    Filed: September 7, 2021
    Publication date: February 3, 2022
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA MATERIALS CO., LTD.
    Inventors: Takayuki NABA, Hiromasa KATO, Keiichi YANO
  • Publication number: 20210398928
    Abstract: A bonded body according to an embodiment includes a substrate, a metal member, and a bonding layer. The bonding layer is provided between the substrate and the metal member. The bonding layer includes a first particle including carbon, a first region including a metal, and a second region including titanium. The second region is provided between the first particle and the first region. A concentration of titanium in the second region is greater than a concentration of titanium in the first region.
    Type: Application
    Filed: September 2, 2021
    Publication date: December 23, 2021
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA MATERIALS CO., LTD.
    Inventors: Maki YONETSU, Seiichi SUENAGA, Sachiko FUJISAWA, Takayuki NABA
  • Patent number: 10952317
    Abstract: A ceramic circuit board comprises: a ceramic substrate with a 1.0 mm thickness or less including a first surface and a second surface, the first surface including a first area and a second area; a first metal plate joined to the first area; and a second metal plate joined to the second surface. The second area has a first waviness profile along a first side of the first surface, the first waviness profile having one extreme value or less. The second area has a second waviness profile along a second side of the first surface, the second waviness profile has not less than two nor more than three extreme values.
    Type: Grant
    Filed: February 4, 2020
    Date of Patent: March 16, 2021
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA MATERIALS CO., LTD.
    Inventors: Takayuki Naba, Hiromasa Kato, Keiichi Yano
  • Patent number: 10872841
    Abstract: The present invention provides a ceramic metal circuit board including a ceramic substrate and metal plates bonded to both surfaces of the ceramic substrate through respective bonding layers, wherein a metal film is provided on a surface of one metal plate bonded to one surface of the ceramic substrate; and at least a part of another metal plate bonded to another surface of the ceramic substrate is not provided with the metal film. Preferably, a protruding portion is formed as a portion of the bonding layer so as to protrude from a side surface of each of the metal plates. According to the above-described configuration, it is possible to provide a ceramic circuit board which is easy to use according to the parts to be bonded and is excellent in heat-cycle resistance characteristics.
    Type: Grant
    Filed: June 1, 2016
    Date of Patent: December 22, 2020
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA MATERIALS CO., LTD.
    Inventors: Takayuki Naba, Hiromasa Kato, Noboru Kitamori
  • Patent number: 10790214
    Abstract: To improve a TCT characteristic of a circuit substrate. The circuit substrate comprises a ceramic substrate including a first and second surfaces, and first and second metal plates respectively bonded to the first and second surfaces via first and second bonding layers. A three-point bending strength of the ceramic substrate is 500 MPa or more. At least one of L1/H1 of a first protruding portion of the first bonding layer and L2/H2 of a second protruding portion of the second bonding layer is 0.5 or more and 3.0 or less. At least one of an average value of first Vickers hardnesses of 10 places of the first protruding portion and an average value of second Vickers hardnesses of 10 places of the second protruding portion is 250 or less.
    Type: Grant
    Filed: September 18, 2019
    Date of Patent: September 29, 2020
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA MATERIALS CO., LTD.
    Inventors: Takayuki Naba, Hiromasa Kato, Masashi Umehara
  • Publication number: 20200178387
    Abstract: A ceramic circuit board comprises: a ceramic substrate with a 1.0 mm thickness or less including a first surface and a second surface, the first surface including a first area and a second area; a first metal plate joined to the first area; and a second metal plate joined to the second surface. The second area has a first waviness profile along a first side of the first surface, the first waviness profile having one extreme value or less. The second area has a second waviness profile along a second side of the first surface, the second waviness profile has not less than two nor more than three extreme values.
    Type: Application
    Filed: February 4, 2020
    Publication date: June 4, 2020
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA MATERIALS CO., LTD.
    Inventors: Takayuki NABA, Hiromasa KATO, Keiichi YANO
  • Patent number: 10595403
    Abstract: A ceramic circuit board comprises: a ceramic substrate with a 1.0 mm thickness or less including a first surface and a second surface, the first surface including a first area and a second area; a first metal plate joined to the first area; and a second metal plate joined to the second surface. The second area has a first waviness profile along a first side of the first surface, the first waviness profile having one extreme value or less. The second area has a second waviness profile along a second side of the first surface, the second waviness profile has not less than two nor more than three extreme values.
    Type: Grant
    Filed: January 11, 2019
    Date of Patent: March 17, 2020
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA MATERIALS CO., LTD.
    Inventors: Takayuki Naba, Hiromasa Kato, Keiichi Yano
  • Publication number: 20200013696
    Abstract: To improve a TCT characteristic of a circuit substrate. The circuit substrate comprises a ceramic substrate including a first and second surfaces, and first and second metal plates respectively bonded to the first and second surfaces via first and second bonding layers. A three-point bending strength of the ceramic substrate is 500 MPa or more. At least one of L1/H1 of a first protruding portion of the first bonding layer and L2/H2 of a second protruding portion of the second bonding layer is 0.5 or more and 3.0 or less. At least one of an average value of first Vickers hardnesses of 10 places of the first protruding portion and an average value of second Vickers hardnesses of 10 places of the second protruding portion is 250 or less.
    Type: Application
    Filed: September 18, 2019
    Publication date: January 9, 2020
    Applicants: Kabushiki Kaisha Toshiba, Toshiba Materials Co., Ltd.
    Inventors: Takayuki NABA, Hiromasa KATO, Masashi UMEHARA
  • Patent number: 10515868
    Abstract: To improve a TCT characteristic of a circuit substrate. The circuit substrate comprises a ceramic substrate including a first and second surfaces, and first and second metal plates respectively bonded to the first and second surfaces via first and second bonding layers. A three-point bending strength of the ceramic substrate is 500 MPa or more. At least one of L1/H1 of a first protruding portion of the first bonding layer and L2/H2 of a second protruding portion of the second bonding layer is 0.5 or more and 3.0 or less. At least one of an average value of first Vickers hardnesses of 10 places of the first protruding portion and an average value of second Vickers hardnesses of 10 places of the second protruding portion is 250 or less.
    Type: Grant
    Filed: August 29, 2017
    Date of Patent: December 24, 2019
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Materials Co., Ltd.
    Inventors: Takayuki Naba, Hiromasa Kato, Masashi Umehara
  • Publication number: 20190385926
    Abstract: According to one embodiment, a ceramic metal circuit board is a ceramic metal circuit board formed by bonding metal circuit plates to at least one surface of a ceramic substrate. At least one of the metal circuit plates has an area of not less than 100 mm2 and includes a concave portion having a depth of not less than 0.02 mm within a range of 1% to 70% of a surface of the at least one of the metal circuit plates. The concave portion is provided not less than 3 mm inside from an end of the metal circuit plate.
    Type: Application
    Filed: August 21, 2019
    Publication date: December 19, 2019
    Inventors: Takayuki NABA, Keiichi YANO, Hiromasa KATO
  • Patent number: 10366938
    Abstract: The present invention provides a silicon nitride circuit board in which metal plates are attached on front and rear sides of a silicon nitride substrate having a three-point flexural strength of 500 MPa or higher, wherein assuming that a thickness of the metal plate on the front side is denoted by t1, and a thickness of the metal plate on the rear side is denoted by t2, a numerical relation: |t1?t2|?0.30 mm is satisfied, and a warp is formed in the silicon nitride substrate so that the silicon nitride substrate is convex toward the metal plate on one of the front side or the rear side; and warp amounts of the silicon nitride substrate in a long-side direction and a short-side direction both fall within a range from 0.01 to 1.0 mm. It is preferable that a longitudinal width (L1) of the silicon nitride substrate falls within a range from 10 to 200 mm, and a transverse width (L2) of the silicon nitride substrate falls within a range from 10 to 200 mm.
    Type: Grant
    Filed: September 6, 2018
    Date of Patent: July 30, 2019
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Materials Co., Ltd.
    Inventors: Hiromasa Kato, Noboru Kitamori, Takayuki Naba, Masashi Umehara
  • Publication number: 20190150278
    Abstract: A ceramic circuit board comprises: a ceramic substrate with a 1.0 mm thickness or less including a first surface and a second surface, the first surface including a first area and a second area; a first metal plate joined to the first area; and a second metal plate joined to the second surface. The second area has a first waviness profile along a first side of the first surface, the first waviness profile having one extreme value or less. The second area has a second waviness profile along a second side of the first surface, the second waviness profile has not less than two nor more than three extreme values.
    Type: Application
    Filed: January 11, 2019
    Publication date: May 16, 2019
    Applicants: Kabushiki Kaisha Toshiba, Toshiba Materials Co., Ltd.
    Inventors: Takayuki NABA, Hiromasa KATO, Keiichi YANO
  • Publication number: 20190006261
    Abstract: The present invention provides a silicon nitride circuit board in which metal plates are attached on front and rear sides of a silicon nitride substrate having a three-point flexural strength of 500 MPa or higher, wherein assuming that a thickness of the metal plate on the front side is denoted by t1, and a thickness of the metal plate on the rear side is denoted by t2, a numerical relation: |t1?t2|?0.30 mm is satisfied, and a warp is formed in the silicon nitride substrate so that the silicon nitride substrate is convex toward the metal plate on one of the front side or the rear side; and warp amounts of the silicon nitride substrate in a long-side direction and a short-side direction both fall within a range from 0.01 to 1.0 mm. It is preferable that a longitudinal width (L1) of the silicon nitride substrate falls within a range from 10 to 200 mm, and a transverse width (L2) of the silicon nitride substrate falls within a range from 10 to 200 mm.
    Type: Application
    Filed: September 6, 2018
    Publication date: January 3, 2019
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA MATERIALS CO., LTD.
    Inventors: Hiromasa KATO, Noboru KITAMORI, Takayuki NABA, Masashi UMEHARA
  • Patent number: 10109555
    Abstract: The present invention provides a silicon nitride circuit board in which metal plates are attached on front and rear sides of a silicon nitride substrate having a three-point flexural strength of 500 MPa or higher, wherein assuming that a thickness of the metal plate on the front side is denoted by t1, and a thickness of the metal plate on the rear side is denoted by t2, a numerical relation: |t1?t2|?0.30 mm is satisfied, and a warp is formed in the silicon nitride substrate so that the silicon nitride substrate is convex toward the metal plate on one of the front side or the rear side; and warp amounts of the silicon nitride substrate in a long-side direction and a short-side direction both fall within a range from 0.01 to 1.0 mm. It is preferable that a longitudinal width (L1) of the silicon nitride substrate falls within a range from 10 to 200 mm, and a transverse width (L2) of the silicon nitride substrate falls within a range from 10 to 200 mm.
    Type: Grant
    Filed: January 26, 2016
    Date of Patent: October 23, 2018
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Materials Co., Ltd.
    Inventors: Hiromasa Kato, Noboru Kitamori, Takayuki Naba, Masashi Umehara
  • Publication number: 20180190568
    Abstract: The present invention provides a ceramic metal circuit board including a ceramic substrate and metal plates bonded to both surfaces of the ceramic substrate through respective bonding layers, wherein a metal film is provided on a surface of one metal plate bonded to one surface of the ceramic substrate; and at least a part of another metal plate bonded to another surface of the ceramic substrate is not provided with the metal film. Preferably, a protruding portion is formed as a portion of the bonding layer so as to protrude from a side surface of each of the metal plates. According to the above-described configuration, it is possible to provide a ceramic circuit board which is easy to use according to the parts to be bonded and is excellent in heat-cycle resistance characteristics.
    Type: Application
    Filed: June 1, 2016
    Publication date: July 5, 2018
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA MATERIALS CO., LTD.
    Inventors: Takayuki NABA, Hiromasa KATO, Noboru KITAMORI
  • Publication number: 20180019182
    Abstract: The present invention provides a silicon nitride circuit board in which metal plates are attached on front and rear sides of a silicon nitride substrate having a three-point flexural strength of 500 MPa or higher, wherein assuming that a thickness of the metal plate on the front side is denoted by t1, and a thickness of the metal plate on the rear side is denoted by t2, a numerical relation: |t1?t2|?0.30 mm is satisfied, and a warp is formed in the silicon nitride substrate so that the silicon nitride substrate is convex toward the metal plate on one of the front side or the rear side; and warp amounts of the silicon nitride substrate in a long-side direction and a short-side direction both fall within a range from 0.01 to 1.0 mm. It is preferable that a longitudinal width (L1) of the silicon nitride substrate falls within a range from 10 to 200 mm, and a transverse width (L2) of the silicon nitride substrate falls within a range from 10 to 200 mm.
    Type: Application
    Filed: January 26, 2016
    Publication date: January 18, 2018
    Applicants: KABUSHIKI KAISHA TOSHIBA, TOSHIBA MATERIALS CO., LTD.
    Inventors: Hiromasa KATO, Noboru KITAMORI, Takayuki NABA, Masashi UMEHARA