Patents by Inventor Tadao Toda

Tadao Toda 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: 20120108011
    Abstract: A semiconductor device capable of stabilizing operations thereof is provided. This semiconductor device comprises a substrate provided with a region having concentrated dislocations at least on part of the back surface thereof, a semiconductor element layer formed on the front surface of the substrate, an insulator film formed on the region of the back surface of the substrate having concentrated dislocations and a back electrode formed to be in contact with a region of the back surface of the substrate other than the region having concentrated dislocations.
    Type: Application
    Filed: December 30, 2011
    Publication date: May 3, 2012
    Applicant: Sanyo Electric Co., Ltd.
    Inventors: Masayuki HATA, Tadao TODA, Shigeyuki OKAMOTO, Daijiro INOUE, Yasuyuki BESSHO, Yasuhiko NOMURA, Tsutomu YAMAGUCHI
  • Patent number: 8101465
    Abstract: A semiconductor device capable of stabilizing operations thereof is provided. This semiconductor device comprises a substrate provided with a region having concentrated dislocations at least on part of the back surface thereof, a semiconductor element layer formed on the front surface of the substrate, an insulator film formed on the region of the back surface of the substrate having concentrated dislocations and a back electrode formed to be in contact with a region of the back surface of the substrate other than the region having concentrated dislocations.
    Type: Grant
    Filed: March 20, 2007
    Date of Patent: January 24, 2012
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Masayuki Hata, Tadao Toda, Shigeyuki Okamoto, Daijiro Inoue
  • Patent number: 7655484
    Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.
    Type: Grant
    Filed: April 26, 2005
    Date of Patent: February 2, 2010
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tadao Toda, Tsutomu Yamaguchi, Masayuki Hata, Yasuhiko Nomura
  • Patent number: 7629623
    Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.
    Type: Grant
    Filed: June 16, 2008
    Date of Patent: December 8, 2009
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tadao Toda, Tsutomu Yamaguchi, Masayuki Hata, Yasuhiko Nomura
  • Patent number: 7589357
    Abstract: A semiconductor device capable of stabilizing operations thereof is provided. This semiconductor device comprises a substrate provided with a region having concentrated dislocations at least on part of the back surface thereof, a semiconductor element layer formed on the front surface of the substrate, an insulator film formed on the region of the back surface of the substrate having concentrated dislocations and a back electrode formed to be in contact with a region of the back surface of the substrate other than the region having concentrated dislocations.
    Type: Grant
    Filed: October 30, 2007
    Date of Patent: September 15, 2009
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Masayuki Hata, Tadao Toda, Shigeyuki Okamoto, Daijiro Inoue, Yasuyuki Bessho, Yasuhiko Nomura, Tsutomu Yamaguchi
  • Publication number: 20080315221
    Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.
    Type: Application
    Filed: June 16, 2008
    Publication date: December 25, 2008
    Inventors: Tadao Toda, Tsutomu Yamaguchi, Masayuki Hata, Yasuhiko Nomura
  • Publication number: 20080179601
    Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.
    Type: Application
    Filed: October 30, 2007
    Publication date: July 31, 2008
    Inventors: Tadao TODA, Tsutomu Yamaguchi, Masayuki Hata, Yasuhiko Nomura
  • Patent number: 7372077
    Abstract: A semiconductor device capable of stabilizing operations thereof is provided. This semiconductor device comprises a substrate provided with a region having concentrated dislocations at least on part of the back surface thereof, a semiconductor element layer formed on the front surface of the substrate, an insulator film formed on the region of the back surface of the substrate having concentrated dislocations and a back electrode formed to be in contact with a region of the back surface of the substrate other than the region having concentrated dislocations.
    Type: Grant
    Filed: January 29, 2004
    Date of Patent: May 13, 2008
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Masayuki Hata, Tadao Toda, Shigeyuki Okamoto, Daijiro Inoue, Yasuyuki Bessho, Yasuhiko Nomura, Tsutomu Yamaguchi
  • Publication number: 20080073664
    Abstract: A semiconductor device capable of stabilizing operations thereof is provided. This semiconductor device comprises a substrate provided with a region having concentrated dislocations at least on part of the back surface thereof, a semiconductor element layer formed on the front surface of the substrate, an insulator film formed on the region of the back surface of the substrate having concentrated dislocations and a back electrode formed to be in contact with a region of the back surface of the substrate other than the region having concentrated dislocations.
    Type: Application
    Filed: October 30, 2007
    Publication date: March 27, 2008
    Applicant: Sanyo Electric Co., Ltd.
    Inventors: Masayuki Hata, Tadao Toda, Shigeyuki Okamoto, Daijiro Inoue, Yasuyuki Bessho, Yasuhiko Nomura, Tsutomu Yamaguchi
  • Publication number: 20080069162
    Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.
    Type: Application
    Filed: October 30, 2007
    Publication date: March 20, 2008
    Inventors: Tadao Toda, Tsutomu Yamaguchi, Masayuki Hata, Yasuhiko Nomura
  • Publication number: 20080067541
    Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.
    Type: Application
    Filed: October 30, 2007
    Publication date: March 20, 2008
    Inventors: Tadao Toda, Tsutomu Yamaguchi, Masayuki Hata, Yasuhiko Nomura
  • Publication number: 20070292979
    Abstract: A semiconductor device capable of stabilizing operations thereof is provided. This semiconductor device comprises a substrate provided with a region having concentrated dislocations at least on part of the back surface thereof, a semiconductor element layer formed on the front surface of the substrate, an insulator film formed on the region of the back surface of the substrate having concentrated dislocations and a back electrode formed to be in contact with a region of the back surface of the substrate other than the region having concentrated dislocations.
    Type: Application
    Filed: March 20, 2007
    Publication date: December 20, 2007
    Applicant: SANYO ELECTRIC CO., LTD.
    Inventors: Masayuki Hata, Tadao Toda, Shigeyuki Okamoto, Daijiro Inoue, Yasuyuki Bessho, Yasuhiko Nomura, Tsutomu Yamaguchi
  • Publication number: 20070235750
    Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.
    Type: Application
    Filed: June 4, 2007
    Publication date: October 11, 2007
    Inventors: Tadao Toda, Tsutomu Yamaguchi, Masayuki Hata, Yasuhiko Nomura
  • Publication number: 20070077669
    Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.
    Type: Application
    Filed: December 4, 2006
    Publication date: April 5, 2007
    Applicant: SANYO ELECTRIC CO., LTD.
    Inventors: Tadao Toda, Tsutomu Yamaguchi, Masayuki Hata, Yasuhiko Nomura
  • Publication number: 20060011946
    Abstract: A nitride semiconductor laser element capable of controlling the lateral confinement of light with a good reproducibility, the nitride semiconductor element comprising an n-type cladding layer (3), an MQW light emitting layer (4) formed on the cladding layer (3), a p-type cladding layer (5) and a p-type contact layer (6) formed on the light emitting layer (4), and an ion implantation light absorbing layer (7) formed, by introducing carbon, in regions other than a current passing region (8) in the cladding layer (5) and the contact layer (6).
    Type: Application
    Filed: February 28, 2003
    Publication date: January 19, 2006
    Inventors: Tadao Toda, Tsutomu Yamaguchi, Masayuki Hata, Yasuhiko Nomura, Masayuki Shouno, Yuuji Hishida, Keiichi Yodoshi, Daijiro Inoue, Takashi Kano, Nobuhiko Hayashi
  • Publication number: 20050191775
    Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.
    Type: Application
    Filed: April 26, 2005
    Publication date: September 1, 2005
    Applicant: SANYO ELECTRIC CO., LTD.
    Inventors: Tadao Toda, Tsutomu Yamaguchi, Masayuki Hata, Yasuhiko Nomura
  • Patent number: 6890779
    Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.
    Type: Grant
    Filed: September 9, 2004
    Date of Patent: May 10, 2005
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tadao Toda, Tsutomu Yamaguchi, Masayuki Hata, Yasuhiko Nomura
  • Publication number: 20050029539
    Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.
    Type: Application
    Filed: September 9, 2004
    Publication date: February 10, 2005
    Applicant: Sanyo Electric Co., Ltd.
    Inventors: Tadao Toda, Tsutomu Yamaguchi, Masayuki Hata, Yasuhiko Nomura
  • Publication number: 20040245540
    Abstract: A semiconductor device capable of stabilizing operations thereof is provided. This semiconductor device comprises a substrate provided with a region having concentrated dislocations at least on part of the back surface thereof, a semiconductor element layer formed on the front surface of the substrate, an insulator film formed on the region of the back surface of the substrate having concentrated dislocations and a back electrode formed to be in contact with a region of the back surface of the substrate other than the region having concentrated dislocations.
    Type: Application
    Filed: January 29, 2004
    Publication date: December 9, 2004
    Inventors: Masayuki Hata, Tadao Toda, Shigeyuki Okamoto, Daijiro Inoue, Yasuyuki Bessho, Yasuhiko Nomura, Tsutomu Yamaguchi
  • Patent number: 6791120
    Abstract: A method of fabricating a nitride-based semiconductor device capable of reducing contact resistance between a nitrogen face of a nitride-based semiconductor substrate or the like and an electrode is provided. This method of fabricating a nitride-based semiconductor device comprises steps of etching the back surface of a first semiconductor layer consisting of either an n-type nitride-based semiconductor layer or a nitride-based semiconductor substrate having a wurtzite structure and thereafter forming an n-side electrode on the etched back surface of the first semiconductor layer.
    Type: Grant
    Filed: March 24, 2003
    Date of Patent: September 14, 2004
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Tadao Toda, Tsutomu Yamaguchi, Masayuki Hata, Yasuhiko Nomura