Patents by Inventor Hisashi Nakayama

Hisashi Nakayama 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: 7834366
    Abstract: A semiconductor device has a substrate, a first Group III nitride semiconductor layer formed on the substrate, a first oxide layer formed in proximity to the upper portions of defects present in the first Group III nitride semiconductor layer, and a second Group III nitride semiconductor layer including a positive layer and formed over each of the first Group III nitride semiconductor layer and the first oxide layer.
    Type: Grant
    Filed: July 24, 2006
    Date of Patent: November 16, 2010
    Assignee: Panasonic Corporation
    Inventors: Hisashi Nakayama, Tetsuzo Ueda, Masaaki Yuri
  • Patent number: 7795630
    Abstract: A semiconductor device, which includes an active layer made of a first semiconductor layer formed on a substrate, is designed so that a first oxidized area made of an oxide layer is formed on the active layer. The first oxidized area further aids in reducing a reactive current so that it becomes possible to achieve a semiconductor device having superior device characteristics.
    Type: Grant
    Filed: August 6, 2004
    Date of Patent: September 14, 2010
    Assignee: Panasonic Corporation
    Inventors: Hisashi Nakayama, Tetsuzo Ueda, Masaaki Yuri, Toshiyuki Takizawa
  • Patent number: 7713812
    Abstract: A substrate with a second semiconductor layer and a second mask film formed thereon is subjected to a heat treatment in an oxidizing atmosphere. Thus, second oxidized regions are formed through oxidization of the second semiconductor layer in regions of the second semiconductor layer that are not covered by the second mask film. At the same time, a second base layer is formed in each region that is interposed by the second oxidized regions. Then, the second mask film is removed, and a third semiconductor layer is selectively grown on the surface of the second base layer that is exposed between the second oxidized regions so as to cover the second oxidized regions, after which the first oxidized regions and the second oxidized regions covering the entire upper surface of the substrate are removed.
    Type: Grant
    Filed: January 12, 2006
    Date of Patent: May 11, 2010
    Assignee: Panasonic Corporation
    Inventors: Tetsuzo Ueda, Hisashi Nakayama, Masaaki Yuri
  • Patent number: 7711023
    Abstract: A semiconductor laser device has a multilayer structure including a first clad layer, an active layer, and a second clad layer stacked successively on a semiconductor substrate in order of increasing distance from the semiconductor substrate. At least one of the first clad layer and the second clad layer has a compressive distortion with respect to the semiconductor substrate. At least one of the first clad layer and the second clad layer includes a semiconductor layer having a tensile distortion with respect to the semiconductor substrate.
    Type: Grant
    Filed: March 26, 2007
    Date of Patent: May 4, 2010
    Assignee: Panasonic Corporation
    Inventors: Yasuhiro Fujimoto, Toru Takayama, Satoshi Murasawa, Hisashi Nakayama, Isao Kidoguchi
  • Patent number: 7704759
    Abstract: In a semiconductor laser device, a plurality of light-emitting elements emitting light with different wavelengths are integrated on a substrate. Each of the light-emitting elements includes, on the substrate, an active layer and cladding layers respectively provided on top and bottom of the active layer. One of the cladding layers provided on top of the active layer is an upper cladding layer having a mesa ridge portion. An etching stopper layer for forming the ridge portion is interposed between the ridge portion and the other portion of the upper cladding layer. The thickness of the etching stopper layer varies among the light-emitting elements.
    Type: Grant
    Filed: September 11, 2008
    Date of Patent: April 27, 2010
    Assignee: Panasonic Corporation
    Inventors: Toru Takayama, Satoshi Murasawa, Yasuhiro Fujimoto, Hisashi Nakayama, Isao Kidoguchi
  • Patent number: 7693202
    Abstract: In a monolithic dual wavelength laser device in which an infrared laser part 100 and a red laser part 130 are built on one n-type GaAs substrate 101, a p-type first cladding layer 105 of the infrared laser part 100 and a p-type first cladding layer 135 of the red laser part 130 are made of the same material and have different impurity concentrations.
    Type: Grant
    Filed: December 14, 2006
    Date of Patent: April 6, 2010
    Assignee: Panasonic Corporation
    Inventors: Satoshi Murasawa, Toru Takayama, Hisashi Nakayama, Yasuhiro Fujimoto, Isao Kidoguchi
  • Publication number: 20090086780
    Abstract: In a monolithic dual wavelength laser device in which an infrared laser part 100 and a red laser part 130 are built on one n-type GaAs substrate 101, a p-type first cladding layer 105 of the infrared laser part 100 and a p-type first cladding layer 135 of the red laser part 130 are made of the same material and have different impurity concentrations.
    Type: Application
    Filed: December 14, 2006
    Publication date: April 2, 2009
    Applicant: Systra
    Inventors: Satoshi Murasawa, Toru Takayama, Hisashi Nakayama, Yasuhiro Fujimoto, Isao Kidoguchi
  • Publication number: 20090017570
    Abstract: In a semiconductor laser device, a plurality of light-emitting elements emitting light with different wavelengths are integrated on a substrate. Each of the light-emitting elements includes, on the substrate, an active layer and cladding layers respectively provided on top and bottom of the active layer. One of the cladding layers provided on top of the active layer is an upper cladding layer having a mesa ridge portion. An etching stopper layer for forming the ridge portion is interposed between the ridge portion and the other portion of the upper cladding layer. The thickness of the etching stopper layer varies among the light-emitting elements.
    Type: Application
    Filed: September 11, 2008
    Publication date: January 15, 2009
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Toru TAKAYAMA, Satoshi Murasawa, Yasuhiro Fujimoto, Hisashi Nakayama, Isao Kidoguchi
  • Patent number: 7433380
    Abstract: In a semiconductor laser device, a plurality of light-emitting elements emitting light with different wavelengths are integrated on a substrate. Each of the light-emitting elements includes, on the substrate, an active layer and cladding layers respectively provided on top and bottom of the active layer. One of the cladding layers provided on top of the active layer is an upper cladding layer having a mesa ridge portion. An etching stopper layer for forming the ridge portion is interposed between the ridge portion and the other portion of the upper cladding layer. The thickness of the etching stopper layer varies among the light-emitting elements.
    Type: Grant
    Filed: August 28, 2006
    Date of Patent: October 7, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Toru Takayama, Satoshi Murasawa, Yasuhiro Fujimoto, Hisashi Nakayama, Isao Kidoguchi
  • Publication number: 20070223550
    Abstract: A semiconductor laser device has a multilayer structure including a first clad layer, an active layer, and a second clad layer stacked successively on a semiconductor substrate in order of increasing distance from the semiconductor substrate. At least one of the first clad layer and the second clad layer has a compressive distortion with respect to the semiconductor substrate. At least one of the first clad layer and the second clad layer includes a semiconductor layer having a tensile distortion with respect to the semiconductor substrate.
    Type: Application
    Filed: March 26, 2007
    Publication date: September 27, 2007
    Inventors: Yasuhiro Fujimoto, Toru Takayama, Satoshi Murasawa, Hisashi Nakayama, Isao Kidoguchi
  • Publication number: 20070147457
    Abstract: In a semiconductor laser device, a plurality of light-emitting elements emitting light with different wavelengths are integrated on a substrate. Each of the light-emitting elements includes, on the substrate, an active layer and cladding layers respectively provided on top and bottom of the active layer. One of the cladding layers provided on top of the active layer is an upper cladding layer having a mesa ridge portion. An etching stopper layer for forming the ridge portion is interposed between the ridge portion and the other portion of the upper cladding layer. The thickness of the etching stopper layer varies among the light-emitting elements.
    Type: Application
    Filed: August 28, 2006
    Publication date: June 28, 2007
    Inventors: Toru Takayama, Satoshi Murasawa, Yasuhiro Fujimoto, Hisashi Nakayama, Isao Kidoguchi
  • Publication number: 20060255350
    Abstract: A semiconductor device has a substrate, a first Group III nitride semiconductor layer formed on the substrate, a first oxide layer formed in proximity to the upper portions of defects present in the first Group III nitride semiconductor layer, and a second Group III nitride semiconductor layer including a positive layer and formed over each of the first Group III nitride semiconductor layer and the first oxide layer.
    Type: Application
    Filed: July 24, 2006
    Publication date: November 16, 2006
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Hisashi Nakayama, Tetsuzo Ueda, Masaaki Yuri
  • Patent number: 7091524
    Abstract: A semiconductor device has a substrate, a first Group III nitride semiconductor layer formed on the substrate, a first oxide layer formed in proximity to the upper portions of defects present in the first Group III nitride semiconductor layer, and a second Group III nitride semiconductor layer including a positive layer and formed over each of the first Group III nitride semiconductor layer and the first oxide layer.
    Type: Grant
    Filed: March 25, 2004
    Date of Patent: August 15, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hisashi Nakayama, Tetsuzo Ueda, Masaaki Yuri
  • Publication number: 20060121695
    Abstract: A substrate with a second semiconductor layer and a second mask film formed thereon is subjected to a heat treatment in an oxidizing atmosphere. Thus, second oxidized regions are formed through oxidization of the second semiconductor layer in regions of the second semiconductor layer that are not covered by the second mask film. At the same time, a second base layer is formed in each region that is interposed by the second oxidized regions. Then, the second mask film is removed, and a third semiconductor layer is selectively grown on the surface of the second base layer that is exposed between the second oxidized regions so as to cover the second oxidized regions, after which the first oxidized regions and the second oxidized regions covering the entire upper surface of the substrate are removed.
    Type: Application
    Filed: January 12, 2006
    Publication date: June 8, 2006
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Tetsuzo Ueda, Hisashi Nakayama, Masaaki Yuri
  • Patent number: 7008839
    Abstract: A substrate with a second semiconductor layer and a second mask film formed thereon is subjected to a heat treatment in an oxidizing atmosphere. Thus, second oxidized regions are formed through oxidization of the second semiconductor layer in regions of the second semiconductor layer that are not covered by the second mask film. At the same time, a second base layer is formed in each region that is interposed by the second oxidized regions. Then, the second mask film is removed, and a third semiconductor layer is selectively grown on the surface of the second base layer that is exposed between the second oxidized regions so as to cover the second oxidized regions, after which the first oxidized regions and the second oxidized regions covering the entire upper surface of the substrate are removed.
    Type: Grant
    Filed: March 7, 2003
    Date of Patent: March 7, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tetsuzo Ueda, Hisashi Nakayama, Masaaki Yuri
  • Publication number: 20050029531
    Abstract: A semiconductor device, which includes an active layer made of a first semiconductor layer formed on a substrate, is designed so that a first oxidized area made of an oxide layer is formed on the active layer.
    Type: Application
    Filed: August 6, 2004
    Publication date: February 10, 2005
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hisashi Nakayama, Tetsuzo Ueda, Masaaki Yuri, Toshiyuki Takizawa
  • Publication number: 20040188693
    Abstract: A semiconductor device has a substrate, a first Group III nitride semiconductor layer formed on the substrate, a first oxide layer formed in proximity to the upper portions of defects present in the first Group III nitride semiconductor layer, and a second Group III nitride semiconductor layer including a positive layer and formed over each of the first Group III nitride semiconductor layer and the first oxide layer.
    Type: Application
    Filed: March 25, 2004
    Publication date: September 30, 2004
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Hisashi Nakayama, Tetsuzo Ueda, Masaaki Yuri
  • Patent number: 6636541
    Abstract: A semiconductor laser device includes a substrate, a p-type cladding layer and a n-type cladding layer provided on the substrate, and an active layer provided between the p-type cladding layer and the n-type cladding layer, having at least two barrier layers and at least two well layers, the barrier layers and the well layers being disposed alternately. Band offsets in a conduction band between the barrier layers and the well layers are provided so as to increase from the n-type cladding layer aide toward the p-type cladding layer side.
    Type: Grant
    Filed: March 2, 2000
    Date of Patent: October 21, 2003
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hisashi Nakayama, Masahiro Kito, Masato Ishino, Yasushi Matsui
  • Publication number: 20030186475
    Abstract: A substrate with a second semiconductor layer and a second mask film formed thereon is subjected to a heat treatment in an oxidizing atmosphere. Thus, second oxidized regions are formed through oxidization of the second semiconductor layer in regions of the second semiconductor layer that are not covered by the second mask film. At the same time, a second base layer is formed in each region that is interposed by the second oxidized regions. Then, the second mask film is removed, and a third semiconductor layer is selectively grown on the surface of the second base layer that is exposed between the second oxidized regions so as to cover the second oxidized regions, after which the first oxidized regions and the second oxidized regions covering the entire upper surface of the substrate are removed.
    Type: Application
    Filed: March 7, 2003
    Publication date: October 2, 2003
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tetsuzo Ueda, Hisashi Nakayama, Masaaki Yuri