Patents by Inventor Katsufumi Kondo

Katsufumi Kondo 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: 11908972
    Abstract: A semiconductor light-emitting device includes a substrate having a first energy bandgap, a first semiconductor layers on the substrate, an active layer on the first semiconductor layer, and a second semiconductor layer on the active layer. The active layer includes a quantum well layer, and a first barrier layer between the first semiconductor layer and the quantum well layer. The first semiconductor layer has a second energy bandgap wider than the first energy bandgap. The quantum well layer has a third energy bandgap narrower than the first and second energy bandgaps. The second semiconductor layer has a fourth energy bandgap wider than the third energy bandgap. The substrate has a refractive index greater than a refractive index of the first semiconductor layer. The refractive index of the first semiconductor layer is not less than a refractive index of the first barrier layer.
    Type: Grant
    Filed: September 3, 2021
    Date of Patent: February 20, 2024
    Assignees: KABUSHIKI KAISHA TOSHIBA, TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION
    Inventors: Akira Tanaka, Hideto Sugawara, Katsufumi Kondo, Masanobu Iwamoto, Kenji Isomoto, Hiroaki Ootsuka
  • Publication number: 20220293817
    Abstract: A semiconductor light-emitting device includes a substrate having a first energy bandgap, a first semiconductor layers on the substrate, an active layer on the first semiconductor layer, and a second semiconductor layer on the active layer. The active layer includes a quantum well layer, and a first barrier layer between the first semiconductor layer and the quantum well layer. The first semiconductor layer has a second energy bandgap wider than the first energy bandgap. The quantum well layer has a third energy bandgap narrower than the first and second energy bandgaps. The second semiconductor layer has a fourth energy bandgap wider than the third energy bandgap. The substrate has a refractive index greater than a refractive index of the first semiconductor layer. The refractive index of the first semiconductor layer is not less than a refractive index of the first barrier layer.
    Type: Application
    Filed: September 3, 2021
    Publication date: September 15, 2022
    Inventors: Akira Tanaka, Hideto Sugawara, Katsufumi Kondo, Masanobu Iwamoto, Kenji Isomoto, Hiroaki Ootsuka
  • Patent number: 9666761
    Abstract: A light-emitting device includes a substrate that is capable of transmitting light, a conductive layer that includes a first conductive portion provided on the substrate and a second conductive portion which is provided on the substrate so as to be adjacent to the first conductive portion, The second conductive portion is thinner than the first conductive portion. A light emitting layer is provided on the first conductive portion. A first electrode is provided on the second conductive portion. A second electrode is provided on the light emitting layer. In some embodiments, a backside surface of the substrate may be processed to be optically rough so as to limit internal reflections.
    Type: Grant
    Filed: March 4, 2016
    Date of Patent: May 30, 2017
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Katsufumi Kondo, Kenji Fujimoto
  • Publication number: 20170077352
    Abstract: A light-emitting device includes a substrate that is capable of transmitting light, a conductive layer that includes a first conductive portion provided on the substrate and a second conductive portion which is provided on the substrate so as to be adjacent to the first conductive portion, The second conductive portion is thinner than the first conductive portion. A light emitting layer is provided on the first conductive portion. A first electrode is provided on the second conductive portion. A second electrode is provided on the light emitting layer. In some embodiments, a backside surface of the substrate may be processed to be optically rough so as to limit internal reflections.
    Type: Application
    Filed: March 4, 2016
    Publication date: March 16, 2017
    Inventors: Katsufumi KONDO, Kenji FUJIMOTO
  • Patent number: 9472713
    Abstract: An embodiment has an emission layer, a first electrode having a reflective metal layer, an insulating layer, first and second conductivity type layers, and a second electrode. The insulating layer is provided on the first electrode and has an opening where a portion of the first electrode is provided. The first conductivity type layer is provided between the insulating layer and the emission layer and has bandgap energy larger than that of the emission layer. The second conductivity type layer is provided on the emission layer and has a current diffusion layer and a second contact layer. The second contact layer is not superimposed on the opening of the insulating layer, and a thickness of the current diffusion layer is larger than that of the first contact layer. The second electrode has a pad portion and a thin portion extends from the pad portion onto the second contact layer.
    Type: Grant
    Filed: November 18, 2013
    Date of Patent: October 18, 2016
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koichi Genei, Tokuhiko Matsunaga, Katsufumi Kondo, Shinji Nunotani
  • Publication number: 20140248729
    Abstract: According to one embodiment, a semiconductor device includes a substrate and a stacked body on the substrate via a joining metal layer. The stacked body includes a device portion and a peripheral portion. The device portion includes from a bottommost layer to a topmost layer included in the stacked body. The peripheral portion surrounding and provided around the device portion; the peripheral portion is a portion of the bottommost layer to the topmost layer included in the stacked body and includes a portion of a semiconductor layer in contact with the joining metal layer.
    Type: Application
    Filed: May 15, 2014
    Publication date: September 4, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Akihiro Fujiwara, Takashi Hakuno, Tokuhiko Matsunaga, Kimitaka Yoshimura, Katsufumi Kondo
  • Patent number: 8816378
    Abstract: According to one embodiment, a light emitting element, includes: a semiconductor stacked body including a light emitting layer; a first upper electrode being connected directly to the semiconductor stacked body; at least one second upper electrode extending from the first upper electrode, the at least one second upper electrode being connected to the semiconductor stacked body via a first contact layer; a lower electrode; a transparent conductive layer; an intermediate film containing oxygen provided between the semiconductor stacked body and the transparent conductive layer; a light reflecting layer; and a current-blocking layer, at least one slit being provided selectively in the current-blocking layer as viewed from a direction perpendicular to a major surface of the light emitting layer.
    Type: Grant
    Filed: June 27, 2013
    Date of Patent: August 26, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shinji Nunotani, Yasuhiko Akaike, Kayo Inoue, Katsufumi Kondo, Tokuhiko Matsunaga
  • Patent number: 8759852
    Abstract: According to one embodiment, a semiconductor device includes a substrate and a stacked body on the substrate via a joining metal layer. The stacked body includes a device portion and a peripheral portion. The device portion includes from a bottommost layer to a topmost layer included in the stacked body. The peripheral portion surrounding and provided around the device portion; the peripheral portion is a portion of the bottommost layer to the topmost layer included in the stacked body and includes a portion of a semiconductor layer in contact with the joining metal layer.
    Type: Grant
    Filed: March 3, 2011
    Date of Patent: June 24, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akihiro Fujiwara, Takashi Hakuno, Tokuhiko Matsunaga, Kimitaka Yoshimura, Katsufumi Kondo
  • Publication number: 20140077221
    Abstract: An embodiment has an emission layer, a first electrode having a reflective metal layer, an insulating layer, first and second conductivity type layers, and a second electrode. The insulating layer is provided on the first electrode and has an opening where a portion of the first electrode is provided. The first conductivity type layer is provided between the insulating layer and the emission layer and has bandgap energy larger than that of the emission layer. The second conductivity type layer is provided on the emission layer and has a current diffusion layer and a second contact layer. The second contact layer is not superimposed on the opening of the insulating layer, and a thickness of the current diffusion layer is larger than that of the first contact layer. The second electrode has a pad portion and a thin portion extends from the pad portion onto the second contact layer.
    Type: Application
    Filed: November 18, 2013
    Publication date: March 20, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Koichi GENEI, Tokuhiko MATSUNAGA, Katsufumi KONDO, Shinji NUNOTANI
  • Publication number: 20130292729
    Abstract: According to one embodiment, a light emitting element, includes: a semiconductor stacked body including a light emitting layer; a first upper electrode being connected directly to the semiconductor stacked body; at least one second upper electrode extending from the first upper electrode, the at least one second upper electrode being connected to the semiconductor stacked body via a first contact layer; a lower electrode; a transparent conductive layer; an intermediate film containing oxygen provided between the semiconductor stacked body and the transparent conductive layer; a light reflecting layer; and a current-blocking layer, at least one slit being provided selectively in the current-blocking layer as viewed from a direction perpendicular to a major surface of the light emitting layer.
    Type: Application
    Filed: June 27, 2013
    Publication date: November 7, 2013
    Inventors: Shinji NUNOTANI, Yasuhiko AKAIKE, Kayo INOUE, Katsufumi KONDO, Tokuhiko MATSUNAGA
  • Publication number: 20130221378
    Abstract: An LED manufacturing method includes the steps of forming a first insulator film on a semiconductor layer, forming a laminated body including a mask layer and an electrode on the first insulator film, forming a second insulator film to cover the laminated body and a first region of the first insulator film where a laminated body is not formed, anisotropic etching the second insulator film to expose the top surface of the mask layer and a second region of the first insulator film, exposing the surface of a semiconductor layer by removing the first insulator film while keeping the first insulator film between the laminated body and the semiconductor layer, removing the mask layer, and forming a clear conducting layer on top of the exposed surface of the semiconductor layer and the electrode.
    Type: Application
    Filed: September 6, 2012
    Publication date: August 29, 2013
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tokuhiko MATSUNAGA, Katsufumi Kondo
  • Patent number: 8395172
    Abstract: According to one embodiment, a light emitting device includes a light emitting layer, a first conductivity type layer, a first electrode, a second conductivity type layer, a current blocking layer and a second electrode. The first conductivity type layer is provided on the light emitting layer. The first electrode is provided on the first conductivity type layer. The second conductivity type layer is provided under the light emitting layer. The current blocking layer is provided in contact with a partial region of a surface of the second conductivity type layer, and has an outer edge protruding from an outer edge of the first electrode. The second electrode is in contact with a surface of the current blocking layer on opposite side from the second conductivity type layer and a region of the surface of the second conductivity type layer not in contact with the current blocking layer.
    Type: Grant
    Filed: December 6, 2010
    Date of Patent: March 12, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akira Tanaka, Katsufumi Kondo, Tokuhiko Matsunaga
  • Patent number: 8384063
    Abstract: A light emitting device includes a stacked body including at least a light emitting layer made of Inx(AlyGa1-y)1-xP(0?x?1, 0?y?1), a p-type cladding layer made of Inx(AlyGa1-y)1-xP (0?x?1, 0?y?1), and a bonding layer made of a semiconductor; and a substrate in which deviation in a lattice constant at a bonding interface with the bonding layer is larger than deviation in lattice constants between the light emitting layer and the bonding layer. The p-type cladding layer is located more distant from the bonding interface than the light emitting layer, and the p-type cladding layer has a carrier concentration of 0.5×1017 cm?3 or more and 3×1017 cm?3 or less.
    Type: Grant
    Filed: January 9, 2012
    Date of Patent: February 26, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Katsufumi Kondo, Ryo Saeki
  • Patent number: 8299480
    Abstract: A semiconductor light emitting device includes: an upper growth layer including a light emitting layer; a transparent substrate through which a radiant light from the light emitting layer passes; and a foundation layer provided between the upper growth layer and the transparent substrate, the foundation layer having a surface-controlling layer and a bonding layer bonded with the transparent substrate. The surface-controlling layer is made of compound semiconductor including at least Ga and As. The upper growth layer is formed on an upper surface of the surface-controlling layer. A lattice constant difference at an interface between the surface-controlling layer and the upper growth layer is smaller than that at an interface between the bonding layer and the transparent substrate.
    Type: Grant
    Filed: February 24, 2009
    Date of Patent: October 30, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Ryo Saeki, Katsufumi Kondo, Yasuo Idei
  • Publication number: 20120119242
    Abstract: According to one embodiment, a light emitting device includes a support body, a first light emitting portion, a second light emitting portion, and a second reflector. The support body includes a first reflector. The first light emitting portion and the second light emitting portion are provided on the support body and include a light emitting layer. Downward directed light of emission light from the light emitting layer is capable of being reflected upward by the first reflector. The second reflector is interposed between the first light emitting portion and the second light emitting portion, provided on the support body, has a cross-sectional shape expanding downward, and includes a side surface metal layer provided on a side surface of the second reflector.
    Type: Application
    Filed: March 21, 2011
    Publication date: May 17, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Katsufumi Kondo
  • Publication number: 20120104357
    Abstract: A light emitting device includes a stacked body including at least a light emitting layer made of Inx(AlyGa1-y)1-xP(0?x?1, 0?y?1), a p-type cladding layer made of Inx(AlyGa1-y)1-xP (0?x?1, 0?y?1), and a bonding layer made of a semiconductor; and a substrate in which deviation in a lattice constant at a bonding interface with the bonding layer is larger than deviation in lattice constants between the light emitting layer and the bonding layer. The p-type cladding layer is located more distant from the bonding interface than the light emitting layer, and the p-type cladding layer has a carrier concentration of 0.5×1017 cm?3 or more and 3×1017 cm?3 or less.
    Type: Application
    Filed: January 9, 2012
    Publication date: May 3, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Katsufumi Kondo, Ryo Saeki
  • Patent number: 8115192
    Abstract: A light emitting device includes a stacked body including at least a light emitting layer made of Inx(AlyGa1-y)1-xP (0?x?1, 0?y?1), a p-type cladding layer made of Inx(AlyGa1-y)1-xP (0?x?1, 0?y?1), and a bonding layer made of a semiconductor; and a substrate in which deviation in a lattice constant at a bonding interface with the bonding layer is larger than deviation in lattice constants between the light emitting layer and the bonding layer. The p-type cladding layer is located more distant from the bonding interface than the light emitting layer, and the p-type cladding layer has a carrier concentration of 0.5×1017 cm?3 or more and 3×1017 cm?3 or less.
    Type: Grant
    Filed: May 1, 2009
    Date of Patent: February 14, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Katsufumi Kondo, Ryo Saeki
  • Publication number: 20120018752
    Abstract: According to one embodiment, a semiconductor device includes a substrate and a stacked body on the substrate via a joining metal layer. The stacked body includes a device portion and a peripheral portion. The device portion includes from a bottommost layer to a topmost layer included in the stacked body. The peripheral portion surrounding and provided around the device portion; the peripheral portion is a portion of the bottommost layer to the topmost layer included in the stacked body and includes a portion of a semiconductor layer in contact with the joining metal layer.
    Type: Application
    Filed: March 3, 2011
    Publication date: January 26, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Akihiro FUJIWARA, Takashi HAKUNO, Tokuhiko MATSUNAGA, Kimitaka YOSHIMURA, Katsufumi KONDO
  • Publication number: 20110291133
    Abstract: According to one embodiment, a light emitting device includes a light emitting layer, a first conductivity type layer, a first electrode, a second conductivity type layer, a current blocking layer and a second electrode. The first conductivity type layer is provided on the light emitting layer. The first electrode is provided on the first conductivity type layer. The second conductivity type layer is provided under the light emitting layer. The current blocking layer is provided in contact with a partial region of a surface of the second conductivity type layer, and has an outer edge protruding from an outer edge of the first electrode. The second electrode is in contact with a surface of the current blocking layer on opposite side from the second conductivity type layer and a region of the surface of the second conductivity type layer not in contact with the current blocking layer.
    Type: Application
    Filed: December 6, 2010
    Publication date: December 1, 2011
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Akira TANAKA, Katsufumi Kondo, Tokuhiko Matsunaga
  • Publication number: 20100065813
    Abstract: A light emitting device includes a stacked body including at least a light emitting layer made of Inx(AlyGa1-y)1-xP (0?x?1, 0?y?1), a p-type cladding layer made of Inx(AlyGa1-y)1-xP (0?x?1, 0?y?1), and a bonding layer made of a semiconductor; and a substrate in which deviation in a lattice constant at a bonding interface with the bonding layer is larger than deviation in lattice constants between the light emitting layer and the bonding layer. The p-type cladding layer is located more distant from the bonding interface than the light emitting layer, and the p-type cladding layer has a carrier concentration of 0.5×1017 cm?3 or more and 3×1017 cm?3 or less.
    Type: Application
    Filed: May 1, 2009
    Publication date: March 18, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Katsufumi Kondo, Ryo Saeki