Patents by Inventor Akihiro Hachigo

Akihiro Hachigo 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: 11094537
    Abstract: Provided are a group III nitride composite substrate having a low sheet resistance and produced with a high yield, and a method for manufacturing the same, as well as a method for manufacturing a group III nitride semiconductor device using the group III nitride composite substrate. A group III nitride composite substrate includes a group III nitride film and a support substrate formed from a material different in chemical composition from the group III nitride film. The group III nitride film is joined to the support substrate in one of a direct manner and an indirect manner. The group III nitride film has a thickness of 10 ?m or more. A sheet resistance of a group III-nitride-film-side main surface is 200 ?/sq or less.
    Type: Grant
    Filed: February 11, 2020
    Date of Patent: August 17, 2021
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Keiji Ishibashi, Akihiro Hachigo, Yuki Hiromura, Naoki Matsumoto, Seiji Nakahata, Fumitake Nakanishi, Takuya Yanagisawa, Koji Uematsu, Yuki Seki, Yoshiyuki Yamamoto, Yusuke Yoshizumi, Hidenori Mikami
  • Publication number: 20200176305
    Abstract: Provided are a group III nitride composite substrate having a low sheet resistance and produced with a high yield, and a method for manufacturing the same, as well as a method for manufacturing a group III nitride semiconductor device using the group III nitride composite substrate. A group III nitride composite substrate includes a group III nitride film and a support substrate formed from a material different in chemical composition from the group III nitride film. The group III nitride film is joined to the support substrate in one of a direct manner and an indirect manner. The group III nitride film has a thickness of 10 ?m or more. A sheet resistance of a group III-nitride-film-side main surface is 200 ?/sq or less.
    Type: Application
    Filed: February 11, 2020
    Publication date: June 4, 2020
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Keiji ISHIBASHI, Akihiro HACHIGO, Yuki HIROMURA, Naoki MATSUMOTO, Seiji NAKAHATA, Fumitake NAKANISHI, Takuya YANAGISAWA, Koji UEMATSU, Yuki SEKI, Yoshiyuki YAMAMOTO, Yusuke YOSHIZUMI, Hidenori MIKAMI
  • Patent number: 10600676
    Abstract: Provided are a group III nitride composite substrate having a low sheet resistance and produced with a high yield, and a method for manufacturing the same, as well as a method for manufacturing a group III nitride semiconductor device using the group III nitride composite substrate. A group III nitride composite substrate includes a group III nitride film and a support substrate formed from a material different in chemical composition from the group III nitride film. The group III nitride film is joined to the support substrate in one of a direct manner and an indirect manner. The group III nitride film has a thickness of 10 ?m or more. A sheet resistance of a group III-nitride-film-side main surface is 200 ?/sq or less.
    Type: Grant
    Filed: January 24, 2018
    Date of Patent: March 24, 2020
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Keiji Ishibashi, Akihiro Hachigo, Yuki Hiromura, Naoki Matsumoto, Seiji Nakahata, Fumitake Nakanishi, Takuya Yanagisawa, Koji Uematsu, Yuki Seki, Yoshiyuki Yamamoto, Yusuke Yoshizumi, Hidenori Mikami
  • Patent number: 10186451
    Abstract: A group III nitride composite substrate includes a group III nitride film and a support substrate formed from a material different in chemical composition from the group III nitride film. The group III nitride film has a thickness of 10 ?m or more. A sheet resistance of a-group III-nitride-film-side main surface of the group III nitride composite substrate is 200 ?/sq or less. A method for manufacturing a group III nitride composite substrate includes the steps of bonding the group III nitride film and the support substrate to each other; and reducing the thickness of at least one of the group III nitride film and the support substrate bonded to each other. Accordingly, a group III nitride composite substrate of a low sheet resistance that is obtained with a high yield as well as a method for manufacturing the same are provided.
    Type: Grant
    Filed: March 4, 2016
    Date of Patent: January 22, 2019
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Akihiro Hachigo, Keiji Ishibashi, Naoki Matsumoto
  • Publication number: 20180166325
    Abstract: Provided are a group III nitride composite substrate having a low sheet resistance and produced with a high yield, and a method for manufacturing the same, as well as a method for manufacturing a group III nitride semiconductor device using the group III nitride composite substrate. A group III nitride composite substrate includes a group III nitride film and a support substrate formed from a material different in chemical composition from the group III nitride film. The group III nitride film is joined to the support substrate in one of a direct manner and an indirect manner. The group III nitride film has a thickness of 10 ?m or more. A sheet resistance of a group III-nitride-film-side main surface is 200 ?/sq or less.
    Type: Application
    Filed: January 24, 2018
    Publication date: June 14, 2018
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Keiji ISHIBASHI, Akihiro HACHIGO, Yuki HIROMURA, Naoki MATSUMOTO, Seiji NAKAHATA, Fumitake NAKANISHI, Takuya YANAGISAWA, Koji UEMATSU, Yuki SEKI, Yoshiyuki YAMAMOTO, Yusuke YOSHIZUMI, Hidenori MIKAMI
  • Patent number: 9917004
    Abstract: Provided are a group III nitride composite substrate having a low sheet resistance and produced with a high yield, and a method for manufacturing the same, as well as a method for manufacturing a group III nitride semiconductor device using the group III nitride composite substrate. A group III nitride composite substrate includes a group III nitride film and a support substrate formed from a material different in chemical composition from the group III nitride film. The group III nitride film is joined to the support substrate in one of a direct manner and an indirect manner. The group III nitride film has a thickness of 10 ?m or more. A sheet resistance of a group III-nitride-film-side main surface is 200 ?/sq or less.
    Type: Grant
    Filed: September 4, 2013
    Date of Patent: March 13, 2018
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Keiji Ishibashi, Akihiro Hachigo, Yuki Hiromura, Naoki Matsumoto, Seiji Nakahata, Fumitake Nakanishi, Takuya Yanagisawa, Koji Uematsu, Yuki Seki, Yoshiyuki Yamamoto, Yusuke Yoshizumi, Hidenori Mikami
  • Publication number: 20160190001
    Abstract: A group III nitride composite substrate includes a group III nitride film and a support substrate formed from a material different in chemical composition from the group III nitride film. The group III nitride film has a thickness of 10 ?m or more. A sheet resistance of a-group III-nitride-film-side main surface of the group III nitride composite substrate is 200 ?/sq or less. A method for manufacturing a group III nitride composite substrate includes the steps of bonding the group III nitride film and the support substrate to each other; and reducing the thickness of at least one of the group III nitride film and the support substrate bonded to each other. Accordingly, a group III nitride composite substrate of a low sheet resistance that is obtained with a high yield as well as a method for manufacturing the same are provided.
    Type: Application
    Filed: March 4, 2016
    Publication date: June 30, 2016
    Inventors: Akihiro HACHIGO, Keiji ISHIBASHI, Naoki MATSUMOTO
  • Patent number: 9312340
    Abstract: A group III nitride composite substrate with a diameter of 75 mm or more includes a support substrate having a thickness ts of 0.1 mm or more and 1 mm or less and a group III nitride film having a thickness tf, thinner than the thickness ts, of 0.01 mm or more and 0.25 mm or less that are bonded to each other. An absolute value |??| of a difference ?? in thermal expansion coefficient determined by subtracting a thermal expansion coefficient ?s of the support substrate from a thermal expansion coefficient ?f of the group III nitride film is 2.2×10?6 K?1 or less. A Young's modulus Es and the thickness ts of the support substrate, a Young's modulus Ef and the thickness tf of the group III nitride film, and the difference ?? in thermal expansion coefficient satisfy a relation: ts2/tf?6Ef·|??|/Es.
    Type: Grant
    Filed: September 4, 2014
    Date of Patent: April 12, 2016
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Makoto Kiyama, Keiji Ishibashi, Akihiro Hachigo, Naoki Matsumoto, Fumitake Nakanishi
  • Patent number: 9312165
    Abstract: A group III nitride composite substrate includes a group III nitride film and a support substrate formed from a material different in chemical composition from the group III nitride film. The group III nitride film has a thickness of 10 ?m or more. A sheet resistance of a-group III-nitride-film-side main surface of the group III nitride composite substrate is 200 ?/sq or less. A method for manufacturing a group III nitride composite substrate includes the steps of bonding the group III nitride film and the support substrate to each other; and reducing the thickness of at least one of the group III nitride film and the support substrate bonded to each other. Accordingly, a group III nitride composite substrate of a low sheet resistance that is obtained with a high yield as well as a method for manufacturing the same are provided.
    Type: Grant
    Filed: December 5, 2013
    Date of Patent: April 12, 2016
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Akihiro Hachigo, Keiji Ishibashi, Naoki Matsumoto
  • Patent number: 9252207
    Abstract: An epitaxial-deposition composite substrate, of more than about 50 mm diameter, in which a nitride-compound semiconductor first substrate is bonded together with a second substrate of either identical or different material. The first substrate is ion-implanted, and on its nitrogen-face side is coated with a special film of thickness within a predetermined range. On a bonding side of the second substrate a special coating of thickness within the predetermined range is formed. The join created by the coated nitrogen-face side of the first substrate being bonded to the coated bonding side of the second substrate occupies at least 90% of the surface area where the two substrates meet.
    Type: Grant
    Filed: December 18, 2013
    Date of Patent: February 2, 2016
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Yoko Maeda, Fumitaka Sato, Akihiro Hachigo, Seiji Nakahata
  • Publication number: 20150349063
    Abstract: A group III nitride composite substrate with a diameter of 75 mm or more includes a support substrate having a thickness ts of 0.1 mm or more and 1 mm or less and a group III nitride film having a thickness tf, thinner than the thickness ts, of 0.01 mm or more and 0.25 mm or less that are bonded to each other. An absolute value |??| of a difference ?? in thermal expansion coefficient determined by subtracting a thermal expansion coefficient ?s of the support substrate from a thermal expansion coefficient ?f of the group III nitride film is 2.2×10?6 K?1 or less. A Young's modulus Es and the thickness ts of the support substrate, a Young's modulus Ef and the thickness tf of the group III nitride film, and the difference ?? in thermal expansion coefficient satisfy a relation: ts2/tf?6Ef·|??|/Es.
    Type: Application
    Filed: September 4, 2014
    Publication date: December 3, 2015
    Inventors: Makoto KIYAMA, Keiji ISHIBASHI, Akihiro HACHIGO, Naoki MATSUMOTO, Fumitake NAKANISHI
  • Patent number: 9136337
    Abstract: A group III nitride composite substrate includes a support substrate and a group III nitride film. A ratio st/mt of a standard deviation st of the thickness of the group III nitride film, to a mean value mt of the thickness thereof is 0.001 or more and 0.2 or less, and a ratio so/mo of a standard deviation so of an absolute value of an off angle between a main surface of the group III nitride film and a plane of a predetermined plane orientation, to a mean value mo of the absolute value of the off angle thereof is 0.005 or more and 0.6 or less. Accordingly, there is provided a low-cost and large-diameter group III nitride composite substrate including a group III nitride film having a large thickness, a small thickness variation, and a high crystal quality.
    Type: Grant
    Filed: September 18, 2013
    Date of Patent: September 15, 2015
    Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Keiji Ishibashi, Akihiro Hachigo, Yuki Hiromura, Naoki Matsumoto, Seiji Nakahata, Fumitake Nakanishi, Yusuke Yoshizumi, Hidenori Mikami
  • Publication number: 20150194442
    Abstract: Provided are a group III nitride composite substrate having a low sheet resistance and produced with a high yield, and a method for manufacturing the same, as well as a method for manufacturing a group III nitride semiconductor device using the group III nitride composite substrate. A group III nitride composite substrate includes a group III nitride film and a support substrate formed from a material different in chemical composition from the group III nitride film. The group III nitride film is joined to the support substrate in one of a direct manner and an indirect manner. The group III nitride film has a thickness of 10 ?m or more. A sheet resistance of a group III-nitride-film-side main surface is 200 ?/sq or less.
    Type: Application
    Filed: September 4, 2013
    Publication date: July 9, 2015
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD
    Inventors: Keiji Ishibashi, Akihiro Hachigo, Yuki Hiromura, Naoki Matsumoto, Seiji Nakahata, Fumitake Nakanishi, Takuya Yanagisawa, Koji Uematsu, Yuki Seki, Yoshiyuki Yamamoto, Yusuke Yoshizumi, Hidenori Mikami
  • Patent number: 8884306
    Abstract: A semiconductor device includes a supporting substrate, a conductive layer placed on the supporting substrate, and at least one group III nitride semiconductor layer placed on the conductive layer. Of the group III nitride semiconductor layers, a conductive-layer-neighboring group III nitride semiconductor layer has n type conductivity, dislocation density of at most 1×107 cm?2, and oxygen concentration of at most 5×1018 cm?3. Thus, an n-down type device having a semiconductor layer of high crystallinity can be provided.
    Type: Grant
    Filed: January 19, 2012
    Date of Patent: November 11, 2014
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takashi Kyono, Kuniaki Ishihara, Akihiro Hachigo, Takahisa Yoshida, Masaki Ueno, Makoto Kiyama
  • Publication number: 20140225229
    Abstract: A group III nitride composite substrate includes a group III nitride film and a support substrate formed from a material different in chemical composition from the group III nitride film. The group III nitride film has a thickness of 10 ?m or more. A sheet resistance of a-group III-nitride-film-side main surface of the group III nitride composite substrate is 200 ?/sq or less. A method for manufacturing a group III nitride composite substrate includes the steps of bonding the group III nitride film and the support substrate to each other; and reducing the thickness of at least one of the group III nitride film and the support substrate bonded to each other. Accordingly, a group III nitride composite substrate of a low sheet resistance that is obtained with a high yield as well as a method for manufacturing the same are provided.
    Type: Application
    Filed: December 5, 2013
    Publication date: August 14, 2014
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Akihiro HACHIGO, Keiji ISHIBASHI, Naoki MATSUMOTO
  • Publication number: 20140103353
    Abstract: A group III nitride composite substrate includes a support substrate and a group III nitride film. A ratio st/mt of a standard deviation st of the thickness of the group III nitride film, to a mean value mt of the thickness thereof is 0.001 or more and 0.2 or less, and a ratio so/mo of a standard deviation so of an absolute value of an off angle between a main surface of the group III nitride film and a plane of a predetermined plane orientation, to a mean value mo of the absolute value of the off angle thereof is 0.005 or more and 0.6 or less. Accordingly, there is provided a low-cost and large-diameter group III nitride composite substrate including a group III nitride film having a large thickness, a small thickness variation, and a high crystal quality.
    Type: Application
    Filed: September 18, 2013
    Publication date: April 17, 2014
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Keiji ISHIBASHI, Akihiro HACHIGO, Yuki HIROMURA, Naoki MATSUMOTO, Seiji NAKAHATA, Fumitake NAKANISHI, Yusuke YOSHIZUMI, Hidenori MIKAMI
  • Publication number: 20140103358
    Abstract: An epitaxial-deposition composite substrate, of more than about 50 mm diameter, in which a nitride-compound semiconductor first substrate is bonded together with a second substrate of either identical or different material. The first substrate is ion-implanted, and on its nitrogen-face side is coated with a special film of thickness within a predetermined range. On a bonding side of the second substrate a special coating of thickness within the predetermined range is formed. The join created by the coated nitrogen-face side of the first substrate being bonded to the coated bonding side of the second substrate occupies at least 90% of the surface area where the two substrates meet.
    Type: Application
    Filed: December 18, 2013
    Publication date: April 17, 2014
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Yoko Maeda, Fumitaka Sato, Akihiro Hachigo, Seiji Nakahata
  • Patent number: 8664085
    Abstract: A composite-substrate manufacturing method is provided with: a step of carrying out implantation of ions through a surface of a bulk substrate composed of the nitride compound semiconductor; a step of setting said surface of the bulk substrate against the second substrate, and bonding the bulk substrate and the second substrate together to obtain a bonded substrate; a step of elevating the temperature of the bonded substrate to a first temperature; a step of sustaining the first temperature for a fixed time; and a step of producing a composite substrate by severing the remaining portion of the bulk substrate from the bonded substrate; characterized in that a predetermined formula as for the first temperature, the thermal expansion coefficient of the first substrate, and the thermal expansion coefficient of the second substrate is satisfied.
    Type: Grant
    Filed: October 17, 2012
    Date of Patent: March 4, 2014
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Yoko Maeda, Fumitaka Sato, Akihiro Hachigo, Seiji Nakahata
  • Publication number: 20130168693
    Abstract: A protective-film-attached composite substrate includes a support substrate, an oxide film disposed on the support substrate, a semiconductor layer disposed on the oxide film, and a protective film protecting the oxide film by covering a portion that is a part of the oxide film and covered with none of the support substrate and the semiconductor layer. A method of manufacturing a semiconductor device includes the steps of: preparing the protective-film-attached composite substrate; and epitaxially growing, on the semiconductor layer of the protective-film-attached composite substrate, at least one functional semiconductor layer causing an essential function of a semiconductor device to be performed. Thus, there are provided a protective-film-attached composite substrate having a large effective region where a high-quality functional semiconductor layer can be epitaxially grown, and a method of manufacturing a semiconductor device in which the protective-film-attached composite substrate is used.
    Type: Application
    Filed: February 13, 2012
    Publication date: July 4, 2013
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Issei Satoh, Hiroaki Yoshida, Yoshiyuki Yamamoto, Akihiro Hachigo, Hideki Matsubara
  • Publication number: 20130032928
    Abstract: A group III nitride composite substrate includes a support substrate, an oxide film formed on the support substrate, and a group III nitride layer formed on the oxide film. The oxide film may be a film selected from the group consisting of a TiO2 film and a SrTiO3 film, and an impurity may be added to the oxide film. Accordingly, the group III nitride composite substrate having a high bonding strength between the support substrate and the group III nitride layer is provided.
    Type: Application
    Filed: November 7, 2011
    Publication date: February 7, 2013
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Issei Satoh, Hiroaki Yoshida, Yoshiyuki Yamamoto, Akihiro Hachigo, Hideki Matsubara