Patents by Inventor Naoki Fukunaga

Naoki Fukunaga 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).

  • Publication number: 20100176418
    Abstract: An object of the present invention is to provide a gallium nitride-based compound semiconductor light emitting device having superior light extraction efficiency and light distribution uniformity. The inventive gallium nitride-based compound semiconductor light emitting device comprises a substrate and a gallium nitride-based compound semiconductor layer stacked on the substrate, wherein on at least one lateral surface of the light emitting device, the bottom (substrate side) of the semiconductor layer is a reverse taper inclined 5 to 85 degrees relative to the substrate main surface and the top of the semiconductor layer is a forward taper inclined 95 to 175 degrees relative to the substrate main surface.
    Type: Application
    Filed: November 8, 2007
    Publication date: July 15, 2010
    Applicant: SHOWA DENKO K.K.
    Inventors: Noritaka Muraki, Naoki Fukunaga
  • Publication number: 20100163886
    Abstract: The present invention provides a gallium nitride compound semiconductor light-emitting device that prevents an increase in the specific resistance of a p-type semiconductor layer due to hydrogen annealing and reduces the specific resistance of a translucent conductive oxide film to lower a driving voltage Vf, a method of manufacturing the same, and a lamp including the same. The method of manufacturing the gallium nitride compound semiconductor light-emitting device includes: forming a positive electrode 15 composed of a translucent conductive oxide film on a p-type GaN layer 14 of a gallium nitride compound semiconductor device; and a hydrogen annealing process of annealing the positive electrode 15 in a gas atmosphere including hydrogen (H2).
    Type: Application
    Filed: March 23, 2007
    Publication date: July 1, 2010
    Applicant: Showa Denko K.K.
    Inventors: Naoki Fukunaga, Hiroshi Osawa
  • Publication number: 20100090604
    Abstract: An LED drive circuit is an LED dive circuit that receives an alternating voltage to drive an LED, and includes a current remove portion that removes a current from a current supply line that supplies an LED drive current to the LED. If an input current to the LED drive circuit is an unnecessary current, the LED does not light because of current removal by the current remove portion. If the input current to the LED drive circuit turns into the LED drive current from the unnecessary current, the current remove portion decreases the amount of current removed.
    Type: Application
    Filed: August 11, 2009
    Publication date: April 15, 2010
    Inventors: Yasuhiro Maruyama, Hiroyuki Shoji, Mitsuru Mariyama, Masakazu Ikeda, Hirohisa Warita, Katsumi Inaba, Naoki Fukunaga
  • Publication number: 20100051981
    Abstract: There is provided a semiconductor light-emitting device having excellent light extraction efficiency and low wavelength unevenness, a manufacturing method thereof, and a lamp. A semiconductor light-emitting device includes an n-type semiconductor layer 12, a light-emitting layer 13, a p-type semiconductor layer 14, and a titanium oxide-based conductive film layer 15 laminated in this order, wherein a random concavo-convex surface 15 is formed on at least a part of the surface of the titanium oxide-based conductive film layer.
    Type: Application
    Filed: August 27, 2008
    Publication date: March 4, 2010
    Applicant: SHOWA DENKO K.K.
    Inventors: Hiroshi OSAWA, Naoki FUKUNAGA, Hironao SHINOHARA
  • Publication number: 20100052007
    Abstract: The present invention provides a light-emitting device comprising an n-type semiconductor layer, a light-emitting layer, a p-type semiconductor layer and a titanium oxide-based conductive film layer laminated in this order, wherein the titanium oxide-based conductive film layer comprises a first layer as a light extraction layer and a second layer as a current diffusion layer, the second layer being arranged on the p-type semiconductor layer side of the first layer, a method of manufacturing a light-emitting device, and a lamp.
    Type: Application
    Filed: August 27, 2008
    Publication date: March 4, 2010
    Applicant: SHOWA DENKO K.K.
    Inventors: Hiroshi OSAWA, Naoki FUKUNAGA, Hironao SHINOHARA
  • Publication number: 20090278158
    Abstract: The present invention provides a gallium nitride based compound semiconductor light-emitting device having high light emission efficiency and a low driving voltage Vf. The gallium nitride based compound semiconductor light-emitting device includes a p-type semiconductor layer, and a transparent conductive oxide film that includes dopants and is formed on the p-type semiconductor layer. A dopant concentration at an interface between the p-type semiconductor layer and the transparent conductive oxide film is higher than the bulk dopant concentration of the transparent conductive oxide film. Therefore, the contact resistance between the p-type semiconductor layer and the transparent conductive oxide film is reduced.
    Type: Application
    Filed: December 13, 2006
    Publication date: November 12, 2009
    Inventors: Naoki Fukunaga, Hironao Shinohara, Hiroshi Osawa
  • Publication number: 20090267109
    Abstract: A compound semiconductor light-emitting device which includes an n-type semiconductor layer, a light-emitting layer and a p-type semiconductor layer, that are made of a compound semiconductor, formed on a substrate, the n-type semiconductor layer and the p-type semiconductor layer are stacked so as to interpose the light-emitting layer therebetween, a first conductive transparent electrode and a second conductive electrode. The first conductive transparent electrode is made of an IZO film containing an In2O3 crystal having a bixbyite structure. Also discussed is a method of manufacturing the device.
    Type: Application
    Filed: December 6, 2007
    Publication date: October 29, 2009
    Applicant: SHOWA DENKO K.K.
    Inventors: Naoki Fukunaga, Hironao Shinohara
  • Publication number: 20090205707
    Abstract: The object of the present invention is to provide a solar cell which is industrially beneficial and has high light conversion efficiency; and a method for producing a solar cell; and the present invention provides a solar cell comprising a substrate, a power generation layer for converting received light into electrical power, a translucent electrode, and another electrode, when light travels through each member from a first surface thereof, a surface opposite to the first surface is defined as a second surface, the power generation layer is formed at a second surface side of the substrate, the translucent electrode is formed on one surface of the power generation layer, and another electrode is formed on the other surface of the power generation layer, wherein the translucent electrode comprises hexagonal In2O3 crystal.
    Type: Application
    Filed: February 18, 2009
    Publication date: August 20, 2009
    Applicant: SHOWA DENKO K.K.
    Inventors: Yoshiaki IKENOUE, Naoki Fukunaga, Hironao Shinohara, Hisayuki Miki, Kenzo Hanawa, Hiroaki Kaji, Hitoshi Yokouchi, Ryoko Konta
  • Publication number: 20090179220
    Abstract: The present invention provides a semiconductor light-emitting device capable of effectively emitting ultraviolet light and a method of manufacturing the same. A semiconductor light-emitting device 1 includes: a p-type semiconductor layer 14; a semiconductor layer that has an emission wavelength in at least an ultraviolet range; and a transparent electrode 15 that is formed on the p-type semiconductor layer 14. The transparent electrode 15 includes a crystallized IZO film.
    Type: Application
    Filed: April 13, 2007
    Publication date: July 16, 2009
    Applicant: SHOWA DENKO K.K.
    Inventors: Naoki Fukunaga, Hiroshi Osawa
  • Publication number: 20090090922
    Abstract: Provided are a method of manufacturing a gallium nitride-based compound semiconductor light-emitting device with a low driving voltage (Vf) and high light outcoupling efficiency, a gallium nitride-based compound semiconductor light-emitting device, and a lamp. In the method of manufacturing the gallium nitride-based compound semiconductor light-emitting device, a transparent conductive oxide film 15 including a dopant is laminated on a p-type semiconductor layer 14 of a gallium nitride-based compound semiconductor device 1. The transparent conductive oxide film 15 is subjected to a laser annealing process using a laser after the lamination of the transparent conductive oxide film 15.
    Type: Application
    Filed: April 23, 2007
    Publication date: April 9, 2009
    Applicant: SHOWA DENKO K.K.
    Inventors: Naoki Fukunaga, Hiroshi Osawa
  • Publication number: 20090008672
    Abstract: There is provided a light-emitting device having high reliability and excellent light extraction efficiency, a manufacturing method thereof, and a lamp. A light-emitting device includes a transparent electrode, wherein a titanium oxide-based conductive film is used for at least one layer of said transparent electrode, an emission wavelength is within a range of 300 to 550 nm, and a photocatalytic reaction-prevention layer is formed so as to cover said titanium oxide-based conductive film.
    Type: Application
    Filed: August 27, 2008
    Publication date: January 8, 2009
    Applicant: SHOWA DENKO K.K.
    Inventors: Hiroshi OSAWA, Naoki FUKUNAGA
  • Publication number: 20090001407
    Abstract: There is provided a semiconductor light-emitting device having excellent light extraction efficiency, a manufacturing method thereof, and a lamp. A semiconductor light-emitting device 1 includes: an n-type semiconductor layer 12, a light-emitting layer 13, a p-type semiconductor layer 14, a titanium oxide-based conductive film layer 15, and a translucent film layer 16 laminated in this order, and a concavo-convex surface is formed on at least a part of the surface of the titanium oxide-based conductive film layer 15.
    Type: Application
    Filed: August 27, 2008
    Publication date: January 1, 2009
    Applicant: SHOWA DENKO K.K.
    Inventors: Hiroshi OSAWA, Naoki FUKUNAGA
  • Publication number: 20070145484
    Abstract: A regulator circuit including an output-stage transistor for supplying a current to an external circuit has an electrostatic protection transistor formed in parallel with the output-stage transistor. The base of the electrostatic protection transistor is connected to, for example, the base of the output-stage transistor, or alternatively to a ground line or to the emitter of the electrostatic protection transistor itself.
    Type: Application
    Filed: November 2, 2006
    Publication date: June 28, 2007
    Inventors: Makoto Hosokawa, Toshihiko Fukushima, Naoki Fukunaga
  • Patent number: 7205880
    Abstract: A trimmer resistance component of the present invention has a trimmer resistor constructed of a p-type diffusion layer formed on the surface of an n-type epitaxial layer. A first electrode is connected to a portion located on one end side of this trimmer resistor, while a first connection portion, a second connection portion and a third connection portion of the second electrode are connected to portions located on the other end side. By cutting a portion of the first connection portion and a portion of the second connection portion by laser trimming, a resistance value between the first electrode and the second electrode can be trimmed without changing a parasitic capacitance between the trimmer resistor and the n-type epitaxial layer.
    Type: Grant
    Filed: November 23, 2004
    Date of Patent: April 17, 2007
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Naoki Fukunaga
  • Publication number: 20050110608
    Abstract: A trimmer resistance component of the present invention has a trimmer resistor constructed of a p-type diffusion layer formed on the surface of an n-type epitaxial layer. A first electrode is connected to a portion located on one end side of this trimmer resistor, while a first connection portion, a second connection portion and a third connection portion of the second electrode are connected to portions located on the other end side. By cutting a portion of the first connection portion and a portion of the second connection portion by laser trimming, a resistance value between the first electrode and the second electrode can be trimmed without changing a parasitic capacitance between the trimmer resistor and the n-type epitaxial layer.
    Type: Application
    Filed: November 23, 2004
    Publication date: May 26, 2005
    Applicant: SHARP KABUSHIKI KAISHA
    Inventor: Naoki Fukunaga
  • Patent number: 6873025
    Abstract: A photodiode includes a first conductivity type semiconductor substrate or a first conductivity type semiconductor layer; a second conductivity type semiconductor layer provided on the first conductivity type semiconductor substrate or the first conductivity type semiconductor layer; an anti-reflection film provided on a surface of a portion of the second conductivity type semiconductor layer which is in a light receiving area; a first conductive layer provided in an area in the vicinity of the light receiving area; and a passivation layer provided on the first conductive layer. Light incident on the photodiode is detected by a junction of the one of the first conductivity type semiconductor substrate and the first conductivity type semiconductor layer, and the second conductivity type semiconductor layer. The area in the vicinity of the light receiving area includes a window area having an opening in the passivation layer for partially exposing the first conductive layer.
    Type: Grant
    Filed: October 30, 2001
    Date of Patent: March 29, 2005
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Hideo Wada, Isamu Ohkubo, Kazuhiro Natsuaki, Naoki Fukunaga, Shigeki Hayashida
  • Patent number: 6600174
    Abstract: A corrosion-resistant conductive layer (TiW layer) formed of a corrosion-resistant material is formed to extend from a bonding pad portion to an interconnection portion of a light receiving element. A semiconductor laser device according to the present invention includes the light receiving element.
    Type: Grant
    Filed: January 11, 2001
    Date of Patent: July 29, 2003
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Isamu Ohkubo, Kazuhiro Natsuaki, Naoki Fukunaga, Masaru Kubo
  • Patent number: 6593165
    Abstract: A circuit-incorporating light receiving device includes an integrated circuit and a photodiode. The integrated circuit and the photodiode are provided on a single semiconductor substrate. The integrated circuit includes a transistor having a polycrystalline silicon as an emitter diffusion source and an electrode. Elements included in the integrated circuit are isolated from each other using local oxidization.
    Type: Grant
    Filed: May 23, 2002
    Date of Patent: July 15, 2003
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Takahiro Takimoto, Naoki Fukunaga, Isamu Ohkubo, Toshimitsu Kasamatsu, Mutsumi Oka, Masaru Kubo
  • Publication number: 20020137246
    Abstract: A circuit-incorporating light receiving device includes an integrated circuit and a photodiode. The integrated circuit and the photodiode are provided on a single semiconductor substrate. The integrated circuit includes a transistor having a polycrystalline silicon as an emitter diffusion source and an electrode. Elements included in the integrated circuit are isolated from each other using local oxidization.
    Type: Application
    Filed: May 23, 2002
    Publication date: September 26, 2002
    Applicant: Sharp Kabushiki Kaisha
    Inventors: Takahiro Takimoto, Naoki Fukunaga, Isamu Ohkubo, Toshimitsu Kasamatsu, Mutsumi Oka, Masaru Kubo
  • Patent number: 6433366
    Abstract: A circuit-incorporating light receiving device includes an integrated circuit and a photodiode. The integrated circuit and the photodiode are provided on a single semiconductor substrate. The integrated circuit includes a transistor having a polycrystalline silicon as an emitter diffusion source and an electrode. Elements included in the integrated circuit are isolated from each other using local oxidization.
    Type: Grant
    Filed: July 14, 2000
    Date of Patent: August 13, 2002
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Takahiro Takimoto, Naoki Fukunaga, Isamu Ohkubo, Toshimitsu Kasamatsu, Mutsumi Oka, Masaru Kubo