Patents by Inventor Taisuke Sato

Taisuke Sato 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: 8809085
    Abstract: According to one embodiment, a method is disclosed for manufacturing a nitride semiconductor device. The method can include removing a growth substrate from a structure body by using a first treatment material. The structure body has the growth substrate, a buffer layer formed on the growth substrate, and the nitride semiconductor layer formed on the buffer layer. A support substrate is bonded to the nitride semiconductor layer. The method can include reducing thicknesses of the buffer layer and the nitride semiconductor layer by using a second treatment material different from the first treatment material after removing the growth substrate.
    Type: Grant
    Filed: August 31, 2011
    Date of Patent: August 19, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Taisuke Sato, Naoharu Sugiyama, Tomonari Shioda, Toshiki Hikosaka, Shinya Nunoue
  • Patent number: 8772800
    Abstract: According to one embodiment, a semiconductor light-emitting device includes: a first conductivity type first semiconductor layer containing a nitride semiconductor crystal and having a tensile stress in a (0001) surface; a second conductivity type second semiconductor layer containing a nitride semiconductor crystal and having a tensile stress in the (0001) surface; a light emitting layer provided between the first semiconductor layer and the second semiconductor layer, containing a nitride semiconductor crystal, and having an average lattice constant larger than the lattice constant of the first semiconductor layer; and a first stress application layer provided on a side opposite to the light emitting layer of the first semiconductor layer and applying a compressive stress to the first semiconductor layer.
    Type: Grant
    Filed: October 21, 2013
    Date of Patent: July 8, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Naoharu Sugiyama, Taisuke Sato, Kotaro Zaima, Jumpei Tajima, Toshiki Hikosaka, Yoshiyuki Harada, Hisashi Yoshida, Shinya Nunoue
  • Patent number: 8766297
    Abstract: According to one embodiment, a semiconductor light emitting device includes a stacked structural body, first and second electrodes, a high resistance layer and a transparent conductive layer. The stacked structural body includes first and second semiconductor layers and a light emitting layer. The first semiconductor layer is disposed between the first electrode and the second semiconductor layer. The second semiconductor layer is disposed between the second electrode and the first semiconductor layer. The second electrode has reflectivity with respect to luminescent light. The high resistance layer is in contact with the second semiconductor layer between the second semiconductor layer and the second electrode and includes a portion overlapping with the first electrode. The transparent conductive layer is in contact with the second semiconductor layer between the second semiconductor layer and the second electrode.
    Type: Grant
    Filed: February 18, 2011
    Date of Patent: July 1, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Toshihide Ito, Toshiyuki Oka, Kotaro Zaima, Taisuke Sato, Shinya Nunoue
  • Patent number: 8766311
    Abstract: According to one embodiment, a semiconductor light emitting device includes a p-type semiconductor layer, an n-type semiconductor layer, a light emitting layer, a p-side electrode and an n-side electrode. The p-type semiconductor layer includes a nitride semiconductor and has a first major surface. The n-type semiconductor layer includes a nitride semiconductor and has a second major surface. The light emitting layer is provided between the n-type semiconductor layer and the p-type semiconductor layer. The p-side electrode contacts a part of the p-type semiconductor layer on the first major surface. The n-side electrode contacts a part of the n-type semiconductor layer on the second major surface. The n-side electrode is provided outside and around the p-side electrode in a plan view along a direction from the p-type semiconductor layer to the n-type semiconductor layer.
    Type: Grant
    Filed: August 10, 2011
    Date of Patent: July 1, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Taisuke Sato, Shigeya Kimura, Kotaro Zaima, Koichi Tachibana, Shinya Nunoue
  • Patent number: 8759851
    Abstract: According to one embodiment, a nitride semiconductor device includes a foundation layer and a functional layer. The foundation layer is formed on an Al-containing nitride semiconductor layer formed on a silicon substrate. The foundation layer has a thickness not less than 1 micrometer and including GaN. The functional layer is provided on the foundation layer. The functional layer includes a first semiconductor layer. The first semiconductor layer has an impurity concentration higher than an impurity concentration in the foundation layer and includes GaN of a first conductivity type.
    Type: Grant
    Filed: July 29, 2013
    Date of Patent: June 24, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomonari Shioda, Hung Hung, Jongil Hwang, Taisuke Sato, Naoharu Sugiyama, Shinya Nunoue
  • Patent number: 8692287
    Abstract: According to one embodiment, a nitride semiconductor device includes: a stacked foundation layer, and a functional layer. The stacked foundation layer is formed on an AlN buffer layer formed on a silicon substrate. The stacked foundation layer includes AlN foundation layers and GaN foundation layers being alternately stacked. The functional layer includes a low-concentration part, and a high-concentration part provided on the low-concentration part. A substrate-side GaN foundation layer closest to the silicon substrate among the plurality of GaN foundation layers includes first and second portions, and a third portion provided between the first and second portions. The third portion has a Si concentration not less than 5×1018 cm?3 and has a thickness smaller than a sum of those of the first and second portions.
    Type: Grant
    Filed: August 31, 2011
    Date of Patent: April 8, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomonari Shioda, Hung Hung, Jongil Hwang, Taisuke Sato, Naoharu Sugiyama, Shinya Nunoue
  • Publication number: 20140048819
    Abstract: According to one embodiment, a semiconductor light-emitting device includes: a first conductivity type first semiconductor layer containing a nitride semiconductor crystal and having a tensile stress in a (0001) surface; a second conductivity type second semiconductor layer containing a nitride semiconductor crystal and having a tensile stress in the (0001) surface; a light emitting layer provided between the first semiconductor layer and the second semiconductor layer, containing a nitride semiconductor crystal, and having an average lattice constant larger than the lattice constant of the first semiconductor layer; and a first stress application layer provided on a side opposite to the light emitting layer of the first semiconductor layer and applying a compressive stress to the first semiconductor layer.
    Type: Application
    Filed: October 21, 2013
    Publication date: February 20, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Naoharu Sugiyama, Taisuke Sato, Kotaro Zaima, Jumpei Tajima, Toshiki Hikosaka, Yoshiyuki Harada, Hisashi Yoshida, Shinya Nunoue
  • Patent number: 8653498
    Abstract: According to one embodiment, a semiconductor light emitting device includes: a stacked structural body, a first electrode; and a second electrode. The stacked structural body includes a first semiconductor layer of n-type, a second semiconductor layer of p-type, and a light emitting portion provided therebetween. The first electrode includes a first contact electrode portion. The second electrode includes a second contact electrode portion and a p-side pad electrode. A sheet resistance of the second contact electrode portion is lower than a sheet resistance of the first semiconductor layer. The p-side pad electrode is provided farther inward than a circumscribed rectangle of the first contact electrode portion, and the first contact electrode portion is provided farther outward than a circumscribed rectangle of the p-side pad electrode.
    Type: Grant
    Filed: February 23, 2011
    Date of Patent: February 18, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shigeya Kimura, Taisuke Sato, Toshihide Ito, Takahiro Sato, Toshiyuki Oka, Shinya Nunoue
  • Patent number: 8643044
    Abstract: According to one embodiment, a semiconductor light emitting device includes: a stacked structure body, first and second electrodes, and a pad layer. The body includes first semiconductor layer of a first conductivity type, a light emitting layer, and a second semiconductor layer of second conductivity type. The first semiconductor layer has first and second portions. The light emitting layer is provided on the second portion. The second semiconductor layer is provided on the light emitting layer. The first electrode is provided on the first portion. The second electrode is provided on the second semiconductor layer and is transmittable to light emitted from the light emitting layer. The pad layer is connected to the second electrode. A transmittance of the pad layer is lower than that of the second electrode. A sheet resistance of the second electrode increases continuously along a direction from the pad layer toward the first electrode.
    Type: Grant
    Filed: August 31, 2011
    Date of Patent: February 4, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koichi Tachibana, Shigeya Kimura, Toshiki Hikosaka, Taisuke Sato, Toshiyuki Oka, Shinya Nunoue
  • Patent number: 8598605
    Abstract: According to one embodiment, a semiconductor light-emitting device includes: a first conductivity type first semiconductor layer containing a nitride semiconductor crystal and having a tensile stress in a (0001) surface; a second conductivity type second semiconductor layer containing a nitride semiconductor crystal and having a tensile stress in the (0001) surface; a light emitting layer provided between the first semiconductor layer and the second semiconductor layer, containing a nitride semiconductor crystal, and having an average lattice constant larger than the lattice constant of the first semiconductor layer; and a first stress application layer provided on a side opposite to the light emitting layer of the first semiconductor layer and applying a compressive stress to the first semiconductor layer.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: December 3, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Naoharu Sugiyama, Taisuke Sato, Kotaro Zaima, Jumpei Tajima, Toshiki Hikosaka, Yoshiyuki Harada, Hisashi Yoshida, Shinya Nunoue
  • Publication number: 20130306981
    Abstract: According to one embodiment, a nitride semiconductor device includes a foundation layer and a functional layer. The foundation layer is formed on an Al-containing nitride semiconductor layer formed on a silicon substrate. The foundation layer has a thickness not less than 1 micrometer and including GaN. The functional layer is provided on the foundation layer. The functional layer includes a first semiconductor layer. The first semiconductor layer has an impurity concentration higher than an impurity concentration in the foundation layer and includes GaN of a first conductivity type.
    Type: Application
    Filed: July 29, 2013
    Publication date: November 21, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Tomonari SHIODA, Hung HUNG, Jongil HWANG, Taisuke SATO, Naoharu SUGIYAMA, Shinya NUNOUE
  • Patent number: 8546178
    Abstract: According to one embodiment, a semiconductor light emitting device includes a substrate, a first semiconductor layer, a light emitting layer, a second semiconductor layer, and a translucent electrode. The substrate includes a first region provided along periphery of a first major surface and a second region provided on center side of the first major surface as viewed from the first region. The first semiconductor layer is provided on the first major surface of the substrate. The light emitting layer is provided on the first semiconductor layer. The second semiconductor layer is provided on the light emitting layer. The translucent electrode is provided on the second semiconductor layer. A reflectance in the second region is higher than a reflectance in the first region.
    Type: Grant
    Filed: July 12, 2011
    Date of Patent: October 1, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomoko Morioka, Takayoshi Fujii, Toshitake Kitagawa, Kazufumi Shiozawa, Taisuke Sato, Hidefumi Yasuda, Yuko Kato
  • Publication number: 20130248921
    Abstract: According to one embodiment, a semiconductor light emitting device includes a stacked structural body, a first electrode, and a second electrode. The stacked structural body includes a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, and a light emitting portion. The stacked structural body has a first major surface on a side of the second semiconductor layer. The first electrode is provided on the first semiconductor. The second electrode is provided on the second semiconductor layer. The first electrode includes a first pad portion and a first extending portion that extends from the first pad portion along a first extending direction. The first extending portion includes a first width-increasing portion. A width of the first width-increasing portion along a direction orthogonal to the first extending direction is increased from the first pad portion toward an end of the first extending portion.
    Type: Application
    Filed: May 13, 2013
    Publication date: September 26, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Shigeya KIMURA, Taisuke SATO, Toshihide ITO, Toshiyuki OKA, Shinya NUNOUE
  • Publication number: 20130244360
    Abstract: According to one embodiment, a method is disclosed for manufacturing a semiconductor light emitting element. The method can include bonding a stacked main body of a structural body to a substrate main body. The structural body includes a growth substrate and the stacked main body provided on the growth substrate. The stacked main body includes a first nitride semiconductor film, a light emitting film provided on the first nitride semiconductor film, and a second nitride semiconductor film provided on the light emitting film. The method can include removing the growth substrate. The method can include forming a plurality of stacked bodies. The method can include forming an uneven portion in a surface of a first nitride semiconductor layer. The method can include forming a plurality of the semiconductor light emitting elements.
    Type: Application
    Filed: August 31, 2012
    Publication date: September 19, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Taisuke SATO, Kotaro Zaima, Jumpei Tajima, Naoharu Sugiyama, Shinya Nunoue
  • Publication number: 20130234178
    Abstract: According to one embodiment, a semiconductor light emitting device includes a silicon substrate, a buffer layer, a foundation semiconductor layer, a first semiconductor layer, a light emitting unit and a second semiconductor layer. The buffer layer is provided on a part of a major surface of the silicon substrate. The foundation semiconductor layer is crystal-grown from an upper surface of the buffer layer, covers a non-formed region of the major surface where the buffer layer is not provided, and is spaced apart from the non-formed region. The first semiconductor layer is provided on the foundation semiconductor layer and has a first conductivity type. The light emitting unit is provided on the first semiconductor layer. The second semiconductor layer is provided on the light emitting unit and has a second conductivity type.
    Type: Application
    Filed: August 31, 2012
    Publication date: September 12, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Satoshi Mitsugi, Naoharu Sugiyama, Taisuke Sato, Shinya Nunoue
  • Publication number: 20130234106
    Abstract: According to one embodiment, a semiconductor light-emitting device includes: a first conductivity type first semiconductor layer containing a nitride semiconductor crystal and having a tensile stress in a (0001) surface; a second conductivity type second semiconductor layer containing a nitride semiconductor crystal and having a tensile stress in the (0001) surface; a light emitting layer provided between the first semiconductor layer and the second semiconductor layer, containing a nitride semiconductor crystal, and having an average lattice constant larger than the lattice constant of the first semiconductor layer; and a first stress application layer provided on a side opposite to the light emitting layer of the first semiconductor layer and applying a compressive stress to the first semiconductor layer.
    Type: Application
    Filed: August 31, 2012
    Publication date: September 12, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Naoharu Sugiyama, Taisuke Sato, Kotaro Zaima, Jumpei Tajima, Toshiki Hikosaka, Yoshiyuki Harada, Hisashi Yoshida, Shinya Nunoue
  • Patent number: 8525194
    Abstract: According to one embodiment, a nitride semiconductor device includes a foundation layer and a functional layer. The foundation layer is formed on an Al-containing nitride semiconductor layer formed on a silicon substrate. The foundation layer has a thickness not less than 1 micrometer and including GaN. The functional layer is provided on the foundation layer. The functional layer includes a first semiconductor layer. The first semiconductor layer has an impurity concentration higher than an impurity concentration in the foundation layer and includes GaN of a first conductivity type.
    Type: Grant
    Filed: August 31, 2011
    Date of Patent: September 3, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomonari Shioda, Hung Hung, Jongil Hwang, Taisuke Sato, Naoharu Sugiyama, Shinya Nunoue
  • Patent number: 8461615
    Abstract: According to one embodiment, a semiconductor light emitting device includes a stacked structural body, a first electrode, and a second electrode. The stacked structural body includes a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type, and a light emitting portion. The stacked structural body has a first major surface on a side of the second semiconductor layer. The first electrode is provided on the first semiconductor. The second electrode is provided on the second semiconductor layer. The first electrode includes a first pad portion and a first extending portion that extends from the first pad portion along a first extending direction. The first extending portion includes a first width-increasing portion. A width of the first width-increasing portion along a direction orthogonal to the first extending direction is increased from the first pad portion toward an end of the first extending portion.
    Type: Grant
    Filed: September 3, 2010
    Date of Patent: June 11, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shigeya Kimura, Taisuke Sato, Toshihide Ito, Toshiyuki Oka, Shinya Nunoue
  • Patent number: 8441023
    Abstract: According to one embodiment, in a light emitting device, a substrate is transparent to a wavelength of emitted light. A first dielectric layer is formed in a first region on the substrate, and has a refractive index smaller than a refractive index of the substrate. A second dielectric layer is formed in a second region on the substrate surrounding the first region, and has a refractive index larger than the refractive index of the substrate. A first semiconductor layer is formed on the first dielectric layer, the second dielectric layer and the substrate. A second semiconductor layer is formed on the first semiconductor layer, and includes an active layer having a PN junction.
    Type: Grant
    Filed: September 6, 2011
    Date of Patent: May 14, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Taisuke Sato, Masanobu Ando, Hajime Nago, Koichi Tachibana, Toshiyuki Oka, Shinya Nunoue
  • Patent number: 8436395
    Abstract: According to one embodiment, a semiconductor light emitting device includes a stacked structure unit, a transparent, p-side and n-side electrodes. The unit includes n-type semiconductor layer, a light emitting portion provided on a part of the n-type semiconductor layer and p-type semiconductor layer provided on the light emitting portion. The transparent electrode is provided on the p-type semiconductor layer. The p-side electrode is provided on the transparent electrode. The n-side electrode is provided on the n-type semiconductor layer. The transparent electrode has a hole provided between the n-side and p-side electrodes. A width of the hole along an axis perpendicular to an axis from the p-side electrode toward the n-side electrode is longer than widths of the n-side and p-side electrodes. A distance between the hole and the n-side electrode is not longer than a distance between the hole and the p-side electrode.
    Type: Grant
    Filed: February 27, 2012
    Date of Patent: May 7, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takahiro Sato, Shigeya Kimura, Taisuke Sato, Toshihide Ito, Koichi Tachibana, Shinya Nunoue