Patents by Inventor Shinichi Nagahama

Shinichi Nagahama 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: 20040004223
    Abstract: A nitride semiconductor device including a light emitting device comprises a n-type region of one or more nitride semiconductor layers having n-type conductivity, a p-type region of one or more nitride semiconductor layers having p-type conductivity and an active layer between the n-type region and the p-type region. In such devices, there is provided with a super lattice layer comprising first layers and second layers which are nitride semiconductors having a different composition respectively. The super lattice structure makes working current and voltage of the device lowered, resulting in realization of more efficient devices.
    Type: Application
    Filed: June 24, 2003
    Publication date: January 8, 2004
    Applicant: Nichia Chemical Industries, Ltd.
    Inventors: Shinichi Nagahama, Masayuki Senoh, Shuji Nakamura
  • Patent number: 6580099
    Abstract: A nitride semiconductor light-emitting device has an active layer of a single-quantum well structure or multi-quantum well made of a nitride semiconductor containing indium and gallium. A first p-type clad layer made of a p-type nitride semiconductor containing aluminum and gallium is provided in contact with one surface of the active layer. A second p-type clad layer made of a p-type nitride semiconductor containing aluminum and gallium is provided on the first p-type clad layer. The second p-type clad layer has a larger band gap than that of the first p-type clad layer. An n-type semiconductor layer is provided in contact with the other surface of the active layer.
    Type: Grant
    Filed: October 11, 2001
    Date of Patent: June 17, 2003
    Assignee: Nichia Chemical Industries, Ltd.
    Inventors: Shuji Nakamura, Shinichi Nagahama, Naruhito Iwasa, Hiroyuki Kiyoku
  • Publication number: 20030015724
    Abstract: A nitride semiconductor device has a nitride semiconductor layer structure. The structure includes an active layer of a quantum well structure containing an indium-containing nitride semiconductor. A first nitride semiconductor layer having a band gap energy larger than that of the active layer is provided in contact with the active layer. A second nitride semiconductor layer having a band gap energy smaller than that of the first layer is provided over the first layer. Further, a third nitride semiconductor layer having a band gap energy larger than that of the second layer is provided over the second layer.
    Type: Application
    Filed: August 28, 2002
    Publication date: January 23, 2003
    Applicant: Nichia Chemical Industries, Ltd.
    Inventors: Shuji Nakamura, Shinichi Nagahama, Naruhito Iwasa
  • Publication number: 20020167019
    Abstract: ? A nitride semiconductor light-emitting device has an active layer of a single-quantum well structure or multi-quantum well made of a nitride semiconductor containing indium and gallium. A first p-type clad layer made of a p-type nitride semiconductor containing aluminum and gallium is provided in contact with one surface of the active layer. A second p-type clad layer made of a p-type nitride semiconductor containing aluminum and gallium is provided on the first p-type clad layer. The second p-type clad layer has a larger band gap than that of the first p-type clad layer. An n-type semiconductor layer is provided in contact with the other surface of the active layer.
    Type: Application
    Filed: October 11, 2001
    Publication date: November 14, 2002
    Applicant: NICHIA CHEMICAL INDUSTRIES, LTD.
    Inventors: Shuji Nakamura, Shinichi Nagahama, Naruhito Iwasa, Hiroyuki Kiyoku
  • Publication number: 20010030318
    Abstract: A nitride semiconductor light-emitting device has an active layer of a single-quantum well structure or multi-quantum well made of a nitride semiconductor containing indium and gallium. A first p-type clad layer made of a p-type nitride semiconductor containing aluminum and gallium is provided in contact with one surface of the active layer. A second p-type clad layer made of a p-type nitride semiconductor containing aluminum and gallium is provided on the first p-type clad layer. The second p-type clad layer has a larger band gap than that of the first p-type clad layer. An n-type semiconductor layer is provided in contact with the other surface of the active layer.
    Type: Application
    Filed: March 16, 2001
    Publication date: October 18, 2001
    Inventors: Shuji Nakamura, Shinichi Nagahama, Naruhito Iwasa, Hiroyuki Kiyoku
  • Patent number: 6172382
    Abstract: A nitride semiconductor device including a light emitting device comprises a n-type region of one or more nitride semiconductor layers having n-type conductivity, a p-type region of one or more nitride semiconductor layers having p-type conductivity and an active layer between the n-type region and the p-type region. In such devices, there is provided with a super lattice layer comprising first layers and second layers which are nitride semiconductors having a different composition respectively. The super lattice structure makes working current and voltage of the device lowered, resulting in realization of more efficient devices.
    Type: Grant
    Filed: January 9, 1998
    Date of Patent: January 9, 2001
    Assignee: Nichia Chemical Industries, Ltd.
    Inventors: Shinichi Nagahama, Masayuki Senoh, Shuji Nakamura
  • Patent number: 5959307
    Abstract: A nitride semiconductor device has a nitride semiconductor layer structure. The structure includes an active layer of a quantum well structure containing an indium-containing nitride semiconductor. A first nitride semiconductor layer having a band gap energy larger than that of the active layer is provided in contact with the active layer. A second nitride semiconductor layer having a band gap energy smaller than that of the first layer is provided over the first layer. Further, a third nitride semiconductor layer having a band gap energy larger than that of the second layer is provided over the second layer.
    Type: Grant
    Filed: November 6, 1996
    Date of Patent: September 28, 1999
    Assignee: Nichia Chemical Industries Ltd.
    Inventors: Shuji Nakamura, Shinichi Nagahama, Naruhito Iwasa
  • Patent number: 5777350
    Abstract: A nitride semiconductor light-emitting device has an active layer of a single-quantum well structure or multi-quantum well made of a nitride semiconductor containing indium and gallium. A first p-type clad layer made of a p-type nitride semiconductor containing aluminum and gallium is provided in contact with one surface of the active layer. A second p-type clad layer made of a p-type nitride semiconductor containing aluminum and gallium is provided on the first p-type clad layer. The second p-type clad layer has a larger band gap than that of the first p-type clad layer. An n-type semiconductor layer is provided in contact with the other surface of the active layer.
    Type: Grant
    Filed: November 30, 1995
    Date of Patent: July 7, 1998
    Assignee: Nichia Chemical Industries, Ltd.
    Inventors: Shuji Nakamura, Shinichi Nagahama, Naruhito Iwasa, Hiroyuki Kiyoku