Patents by Inventor Taichiroo Konno

Taichiroo Konno 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: 20080093612
    Abstract: A plurality of semiconductor layers including an active layer 6 and a light extract layer 4, and a reflective metal film 11 are formed in a semiconductor light emitting device. The light extract layer 4 is formed of a plurality of layers 23, 24 having different composition ratios. An irregularity 22 is formed on the layers 23, 24 including an outermost layer to provide a main surface S as a rough-surface.
    Type: Application
    Filed: October 19, 2007
    Publication date: April 24, 2008
    Applicant: HITACHI CABLE, LTD.
    Inventors: Taichiroo Konno, Kazuyuki Iizuka, Masahiro Arai
  • Publication number: 20080093619
    Abstract: A first conductivity type cladding layer 2, a first side multilayer 9, an active layer 4, a second side multilayer 10, and a second conductivity type cladding layer 3 are provided in a semiconductor light emitting device. The first side multilayer 9 is provided between the first conductivity type cladding layer 2 and the active layer 4, and the second side multilayer 10 is provided between the active layer 4 and the second conductivity type cladding layer 3. Each of the multilayer 9, 10 is transparent with respect to the light generated at the active layer 4, having a bandgap larger than that of the active layer 4, and lattice-matched with the active layer 4.
    Type: Application
    Filed: October 18, 2007
    Publication date: April 24, 2008
    Applicant: Hitachi Cable, Ltd.
    Inventors: Taichiroo Konno, Takashi Furuya
  • Publication number: 20080083919
    Abstract: On a GaAs substrate 1, a light emitting part 4, an intermediate layer 5 of AlGaInP and a current spreading layer 6 are sequentially formed. The light emitting part 4 includes a first conductivity type AlGaInP based lower cladding layer 41, an AlGaInP based light emitting layer 42, and a second conductivity type AlGaInP based upper cladding layer 43 sequentially formed on the GaAs substrate 1. In each layer of the light emitting part 4, a hydrogen concentration is not more than 2×1017 cm?3, a carbon concentration is not more than 2×1016 cm?3, and an oxygen concentration is not more than 2×1016 cm?3. In a partial region or in a total region of the current-spreading layer 6, a hydrogen concentration is not more than 5×1017 cm?3, a carbon concentration is not more than 5×1017 cm?3, and an oxygen concentration is not more than 2×1016 cm?3.
    Type: Application
    Filed: August 31, 2007
    Publication date: April 10, 2008
    Inventors: Ken TAKAHASHI, Taichiroo Konno, Masahiro Arai
  • Patent number: 7230281
    Abstract: A semiconductor light emitting device has: a semiconductor substrate; a semiconductor layer having an n-type cladding layer, an active layer, a p-type cladding layer and a p-type contact layer, wherein the p-type contact layer is made of an As-based material and located at the top of the semiconductor layer and doped with a p-type dopant at a concentration of 1×1019/cm3 or more; a current spreading layer formed on the semiconductor layer and made of a metal oxide material; and a diffusion prevention layer formed between the p-type contact layer and the p-type cladding layer. The diffusion prevention layer is made of a group III–V semiconductor that has phosphorus as a group V element and has a crystal lattice mismatch ratio of within ±0.3% to the semiconductor substrate.
    Type: Grant
    Filed: June 24, 2005
    Date of Patent: June 12, 2007
    Assignee: Hitachi Cable, Ltd.
    Inventors: Masahiro Arai, Taichiroo Konno, Kazuyuki Iizuka
  • Publication number: 20070075321
    Abstract: A semiconductor light-emitting device having: a light-emitting portion formed on a semiconductor substrate, the light-emitting portion having an n-type clad layer, an active layer and a p-type clad layer; an As-based contact layer formed on the light-emitting portion, the contact layer being doped with a p-type dopant of 1×1019/cm3 or more; a current spreading layer formed on the contact layer, the current spreading layer being formed of a transparent conductive film of a metal oxide material; and a buffer layer formed between the contact layer and the p-type clad layer or formed being inserted inside of the p-type clad layer. The buffer layer is of an undoped group III/V semiconductor, and the group III/V semiconductor is of a group V element having P(phosphorus) as a main component thereof.
    Type: Application
    Filed: August 2, 2006
    Publication date: April 5, 2007
    Inventors: Taichiroo Konno, Kazuyuki Iizuka, Masahiro Arai
  • Publication number: 20070075327
    Abstract: A semiconductor light emitting device has a light-emitting portion formed on a semiconductor substrate, an As-based p-type contact layer formed thereon, a current spreading layer formed thereon of a metal oxide material, and a buffer layer formed between the p-type cladding layer and the p-type contact layer. The buffer layer has a group III/V semiconductor with a p-type conductivity and hydrogen or carbon included intentionally or unavoidably therein, and the buffer layer has a thickness equal to or greater than a diffusion length L of a dopant doped into the p-type contact layer.
    Type: Application
    Filed: July 13, 2006
    Publication date: April 5, 2007
    Inventors: Masahiro Arai, Taichiroo Konno, Kazuyuki Iizuka, Katsuya Akimoto
  • Publication number: 20070075328
    Abstract: A semiconductor light-emitting device has a semiconductor substrate, an n-type cladding layer, an active layer, a p-type cladding layer, a p-type buffer layer, a p-type contact layer, and a current spreading layer. A part or all of the p-type buffer layer has a low Mg concentration buffer layer with a Mg concentration of 3.0×1017/cm3 or less and a film thickness of 50 nm or more.
    Type: Application
    Filed: August 29, 2006
    Publication date: April 5, 2007
    Inventors: Kazuyuki Iizuka, Taichiroo Konno, Masahiro Arai
  • Publication number: 20070075319
    Abstract: A semiconductor light-emitting device with a transparent conductive film has: a light-emitting portion formed on a semiconductor substrate, the light-emitting portion having an n-type clad layer, an active layer and a p-type clad layer; an As-based contact layer formed on the light-emitting portion, the contact layer being doped with a p-type dopant of 1×1019/cm3 or more; a current spreading layer formed on the contact layer, the current spreading layer being formed of a transparent conductive film made of a metal oxide material; and a buffer layer formed between the contact layer and the p-type clad layer. The buffer layer has two or more buffer layer parts, and the adjacent buffer layer parts are different each other in material or composition.
    Type: Application
    Filed: July 13, 2006
    Publication date: April 5, 2007
    Inventors: Taichiroo Konno, Kazuyuki Iizuka, Masahiro Arai
  • Publication number: 20070023768
    Abstract: A semiconductor light emitting element has a first conductive-type cladding layer, an undoped active layer, a second conductive-type cladding layer, and a second conductive-type current spreading layer that are formed on a first conductive-type semiconductor substrate. The second conductive-type cladding layer has a first dopant suppressing layer formed at a portion in the second conductive-type cladding layer, the portion being not in contact with the active layer. The first dopant suppressing layer has a dopant concentration lower than a region in the vicinity of the first dopant suppressing layer.
    Type: Application
    Filed: November 23, 2005
    Publication date: February 1, 2007
    Applicant: Hitachi Cable, Ltd.
    Inventors: Taichiroo Konno, Kazuyuki Iizuka, Masahiro Arai, Takashi Furuya
  • Publication number: 20060220032
    Abstract: A semiconductor light emitting device has: a semiconductor substrate; a semiconductor layer having an n-type cladding layer, an active layer, a p-type cladding layer and a p-type contact layer, wherein the p-type contact layer is made of an As-based material and located at the top of the semiconductor layer and doped with a p-type dopant at a concentration of 1×1019/cm3 or more; a current spreading layer formed on the semiconductor layer and made of a metal oxide material; and a diffusion prevention layer formed between the p-type contact layer and the p-type cladding layer. The diffusion prevention layer is made of a group III-V semiconductor that has phosphorus as a group V element and has a crystal lattice mismatch ratio of within ±0.3% to the semiconductor substrate.
    Type: Application
    Filed: June 24, 2005
    Publication date: October 5, 2006
    Applicant: Hitachi Cable, Ltd.
    Inventors: Masahiro Arai, Taichiroo Konno, Kazuyuki Iizuka
  • Publication number: 20040227151
    Abstract: In a light emitting diode, a light-emitting region is including an active layer provided between a first conductivity type cladding layer formed on the semiconductor substrate and a second conductivity type cladding layer. A transparent conductive film made of a metal oxide is located over the light-emitting region. A layer for preventing exfoliation of the transparent conductive film, the preventing layer being made of a compound semiconductor contains at least aluminum and is located between the light-emitting region and the transparent conductive film. The layer for preventing exfoliation of the transparent conductive film contains a conductivity type determination impurity in a concentration of 1×1019 cm−3 or higher.
    Type: Application
    Filed: March 24, 2004
    Publication date: November 18, 2004
    Applicant: HITACHI CABLE, LTD.
    Inventors: Taichiroo Konno, Masahiro Arai