Patents by Inventor Kenichi Tokano

Kenichi Tokano 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: 8431992
    Abstract: A single crystal semiconductor layer of a first conduction type is disposed on a surface of a semiconductor substrate. A plurality of trenches are provided in the semiconductor layer to form a plurality of first semiconductor regions of the first conduction type at intervals in a direction parallel to the surface. An epitaxial layer is buried in the plurality of trenches to form a plurality of second semiconductor regions of a second conduction type. The plurality of second semiconductor regions each includes an outer portion with a high impurity concentration formed against an inner wall of the trench, and an inner portion with a low impurity concentration formed inner than the outer portion.
    Type: Grant
    Filed: February 8, 2011
    Date of Patent: April 30, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kenichi Tokano, Tetsuo Matsuda, Wataru Saito
  • Publication number: 20110133278
    Abstract: A single crystal semiconductor layer of a first conduction type is disposed on a surface of a semiconductor substrate. A plurality of trenches are provided in the semiconductor layer to form a plurality of first semiconductor regions of the first conduction type at intervals in a direction parallel to the surface. An epitaxial layer is buried in the plurality of trenches to form a plurality of second semiconductor regions of a second conduction type. The plurality of second semiconductor regions each includes an outer portion with a high impurity concentration formed against an inner wall of the trench, and an inner portion with a low impurity concentration formed inner than the outer portion.
    Type: Application
    Filed: February 8, 2011
    Publication date: June 9, 2011
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Kenichi TOKANO, Tetsuo Matsuda, Wataru Saito
  • Patent number: 7936015
    Abstract: A single crystal semiconductor layer of a first conduction type is disposed on a surface of a semiconductor substrate. A plurality of trenches are provided in the semiconductor layer to form a plurality of first semiconductor regions of the first conduction type at intervals in a direction parallel to the surface. An epitaxial layer is buried in the plurality of trenches to form a plurality of second semiconductor regions of a second conduction type. The plurality of second semiconductor regions each includes an outer portion with a high impurity concentration formed against an inner wall of the trench, and an inner portion with a low impurity concentration formed inner than the outer portion.
    Type: Grant
    Filed: August 18, 2009
    Date of Patent: May 3, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kenichi Tokano, Tetsuo Matsuda, Wataru Saito
  • Patent number: 7898031
    Abstract: A single crystal semiconductor layer of a first conduction type is disposed on a surface of a semiconductor substrate. A plurality of trenches are provided in the semiconductor layer to form a plurality of first semiconductor regions of the first conduction type at intervals in a direction parallel to the surface. An epitaxial layer is buried in the plurality of trenches to form a plurality of second semiconductor regions of a second conduction type. The plurality of second semiconductor regions each includes an outer portion with a high impurity concentration formed against an inner wall of the trench, and an inner portion with a low impurity concentration formed inner than the outer portion.
    Type: Grant
    Filed: June 23, 2010
    Date of Patent: March 1, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kenichi Tokano, Tetsuo Matsuda, Wataru Saito
  • Publication number: 20100258854
    Abstract: A single crystal semiconductor layer of a first conduction type is disposed on a surface of a semiconductor substrate. A plurality of trenches are provided in the semiconductor layer to form a plurality of first semiconductor regions of the first conduction type at intervals in a direction parallel to the surface. An epitaxial layer is buried in the plurality of trenches to form a plurality of second semiconductor regions of a second conduction type. The plurality of second semiconductor regions each includes an outer portion with a high impurity concentration formed against an inner wall of the trench, and an inner portion with a low impurity concentration formed inner than the outer portion.
    Type: Application
    Filed: June 23, 2010
    Publication date: October 14, 2010
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Kenichi TOKANO, Tetsuo Matsuda, Wataru Saito
  • Patent number: 7714385
    Abstract: A semiconductor device, including a first semiconductor layer of the first conductivity type having a plurality of trenches formed therein. A second semiconductor layer of the second conductivity type composed of an epitaxial layer is buried in the trenches in the first semiconductor layer. The trench has surface orientations including a surface orientation of a sidewall at an upper stage made slower in epitaxial growth speed than a surface orientation of a sidewall at a lower stage.
    Type: Grant
    Filed: December 22, 2006
    Date of Patent: May 11, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kenichi Tokano, Hiroyuki Sugaya
  • Publication number: 20090302373
    Abstract: A single crystal semiconductor layer of a first conduction type is disposed on a surface of a semiconductor substrate. A plurality of trenches are provided in the semiconductor layer to form a plurality of first semiconductor regions of the first conduction type at intervals in a direction parallel to the surface. An epitaxial layer is buried in the plurality of trenches to form a plurality of second semiconductor regions of a second conduction type. The plurality of second semiconductor regions each includes an outer portion with a high impurity concentration formed against an inner wall of the trench, and an inner portion with a low impurity concentration formed inner than the outer portion.
    Type: Application
    Filed: August 18, 2009
    Publication date: December 10, 2009
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Kenichi TOKANO, Tetsuo Matsuda, Wataru Saito
  • Patent number: 7595530
    Abstract: A single crystal semiconductor layer of a first conduction type is disposed on a surface of a semiconductor substrate. A plurality of trenches are provided in the semiconductor layer to form a plurality of first semiconductor regions of the first conduction type at intervals in a direction parallel to the surface. An epitaxial layer is buried in the plurality of trenches to form a plurality of second semiconductor regions of a second conduction type. The plurality of second semiconductor regions each includes an outer portion with a high impurity concentration formed against an inner wall of the trench, and an inner portion with a low impurity concentration formed inner than the outer portion.
    Type: Grant
    Filed: March 1, 2006
    Date of Patent: September 29, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kenichi Tokano, Tetsuo Matsuda, Wataru Saito
  • Patent number: 7531871
    Abstract: A semiconductor element of this invention includes a drift layer of a first conductivity type formed on a semiconductor substrate of the first conductivity type, a well layer of a second conductivity type selectively formed in the surface of the drift layer, a source layer of the first conductivity type selectively formed in the surface of the well layer, a trench formed to reach at least the inside of the drift layer from the surface of the source layer through the well layer, a buried electrode formed in the trench through a first insulating film, and a control electrode formed on the drift layer, the well layer, and the source layer through a second insulating film.
    Type: Grant
    Filed: December 5, 2005
    Date of Patent: May 12, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Ichiro Omura, Wataru Saito, Tsuneo Ogura, Hiromichi Ohashi, Yoshihiko Saito, Kenichi Tokano
  • Patent number: 7488993
    Abstract: A semiconductor device, includes: a semiconductor substrate of 100 micrometers or less in thickness; an electrode pattern formed above the semiconductor substrate; and an insulation film of 50 micrometers or greater in thickness residing on parts of the upper surface side of the semiconductor substrate other than at least on the electrode pattern.
    Type: Grant
    Filed: February 28, 2005
    Date of Patent: February 10, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kenichi Tokano, Motoshige Kobayashi, Kazuyuki Saito
  • Patent number: 7423315
    Abstract: The present application provides a semiconductor device including a first-conductivity type semiconductor substrate, a pillar structure portion formed on the first-conductivity type semiconductor substrate and formed of five semiconductor pillar layers arranged in one direction parallel to a main surface of the first-conductivity type semiconductor substrate, and isolation insulating portions formed on the first-conductivity type semiconductor substrate and sandwiching the pillar structure portion between the isolation insulating portions, wherein the pillar structure portion is formed of a first first-conductivity type pillar layer, a second first-conductivity type pillar layer and a third first-conductivity type pillar layer which sandwich the first first-conductivity type pillar layer, a first second-conductivity type pillar layer provided between the first first-conductivity type pillar layer and the second first-conductivity type pillar layer, and a second second-conductivity type pillar layer provided b
    Type: Grant
    Filed: November 3, 2005
    Date of Patent: September 9, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideki Okumura, Hitoshi Kobayashi, Masanobu Tsuchitani, Satoshi Aida, Shigeo Kouzuki, Masaru Izumisawa, Satoshi Taji, Kenichi Tokano
  • Patent number: 7391077
    Abstract: Provided is a semiconductor device including a semiconductor substrate which includes a first semiconductor layer of a first conductivity and a pair of second semiconductor layers disposed on the first semiconductor layer and spaced apart from each other to form a trench therebetween, wherein the second semiconductor layer includes a first impurity-diffused region of the first conductivity extending from a lower surface toward an upper surface of the second semiconductor layer, and a second impurity-diffused region of a second conductivity which extends from the lower surface toward the upper surface and is adjacent to the first impurity-diffused region, an insulating layer covering a sidewall of the trench, and a cap layer which is in contact with the semiconductor substrate and covers an opening of the trench to form an enclosed space in the trench, a material of the cap layer being almost the same as that of the semiconductor substrate.
    Type: Grant
    Filed: November 9, 2004
    Date of Patent: June 24, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kenichi Tokano, Atsuko Yamashita, Koichi Takahashi, Hideki Okumura, Shingo Sato
  • Patent number: 7301202
    Abstract: A semiconductor substrate of a first conduction type is provided for serving as a common drain to a plurality of power MISFET cells. A middle semiconductor layer is formed on the semiconductor substrate and has a lower impurity concentration than that of the semiconductor substrate. Pillar regions are formed on the middle semiconductor layer and include semiconductor regions of the first conduction type having a lower impurity concentration than that of the middle semiconductor layer.
    Type: Grant
    Filed: June 14, 2005
    Date of Patent: November 27, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shigeo Kouzuki, Hideki Okumura, Wataru Saito, Masaru Izumisawa, Masahiko Shiomi, Hitoshi Kobayashi, Kenichi Tokano, Satoshi Yanagisawa, Hironori Yoshioka, Manabu Kimura
  • Publication number: 20070148931
    Abstract: The present invention provides a semiconductor device, which comprises a first semiconductor layer of the first conductivity type having a plurality of trenches formed therein. A second semiconductor layer of the second conductivity type composed of an epitaxial layer is buried in the trenches in the first semiconductor layer. The trench has surface orientations including a surface orientation of a sidewall at an upper stage made slower in epitaxial growth speed than a surface orientation of a sidewall at a lower stage.
    Type: Application
    Filed: December 22, 2006
    Publication date: June 28, 2007
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Kenichi Tokano, Hiroyuki Sugaya
  • Publication number: 20060197152
    Abstract: A single crystal semiconductor layer of a first conduction type is disposed on a surface of a semiconductor substrate. A plurality of trenches are provided in the semiconductor layer to form a plurality of first semiconductor regions of the first conduction type at intervals in a direction parallel to the surface. An epitaxial layer is buried in the plurality of trenches to form a plurality of second semiconductor regions of a second conduction type. The plurality of second semiconductor regions each includes an outer portion with a high impurity concentration formed against an inner wall of the trench, and an inner portion with a low impurity concentration formed inner than the outer portion.
    Type: Application
    Filed: March 1, 2006
    Publication date: September 7, 2006
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Kenichi Tokano, Tetsuo Matsuda, Wataru Saito
  • Patent number: 7075149
    Abstract: A semiconductor device comprises: a semiconductor layer of a first conductivity type; a first semiconductor pillar layer of the first conductivity type; a second semiconductor pillar layer of a second conductivity type; a third semiconductor pillar layer of the first conductivity type; a forth semiconductor pillar layer of the second conductivity type; a fifth semiconductor pillar layer of the first conductivity type provided on the major surface of the semiconductor layer; a first semiconductor base layer of the second conductivity type provided on the second semiconductor pillar layer; a second semiconductor base layer of the second conductivity type provided on the forth semiconductor pillar layer; first semiconductor region of the first conductivity type selectively provided on a surface of the first semiconductor base layer; second semiconductor region of the first conductivity type selectively provided on a surface of the second semiconductor base layer; gate insulating film provided on the first semico
    Type: Grant
    Filed: May 13, 2004
    Date of Patent: July 11, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shingo Sato, Atsuko Yamashita, Hideki Okumura, Kenichi Tokano
  • Publication number: 20060145230
    Abstract: A semiconductor element of this invention includes a drift layer of a first conductivity type formed on a semiconductor substrate of the first conductivity type, a well layer of a second conductivity type selectively formed in the surface of the drift layer, a source layer of the first conductivity type selectively formed in the surface of the well layer, a trench formed to reach at least the inside of the drift layer from the surface of the source layer through the well layer, a buried electrode formed in the trench through a first insulating film, and a control electrode formed on the drift layer, the well layer, and the source layer through a second insulating film.
    Type: Application
    Filed: December 5, 2005
    Publication date: July 6, 2006
    Inventors: Ichiro Omura, Wataru Saito, Tsuneo Ogura, Hiromichi Ohashi, Yoshihiko Saito, Kenichi Tokano
  • Publication number: 20060138536
    Abstract: A semiconductor substrate of a first conduction type is provided for serving as a common drain to a plurality of power MISFET cells. A middle semiconductor layer is formed on the semiconductor substrate and has a lower impurity concentration than that of the semiconductor substrate. Pillar regions are formed on the middle semiconductor layer and include semiconductor regions of the first conduction type having a lower impurity concentration than that of the middle semiconductor layer.
    Type: Application
    Filed: June 14, 2005
    Publication date: June 29, 2006
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Shigeo Kouzuki, Hideki Okumura, Wataru Saito, Masaru Izumisawa, Masahiko Shiomi, Hitoshi Kobayashi, Kenichi Tokano, Satoshi Yanagisawa, Hironori Yoshioka, Manabu Kimura
  • Patent number: 7067870
    Abstract: A semiconductor element of this invention includes a drift layer of a first conductivity type formed on a semiconductor substrate of the first conductivity type, a well layer of a second conductivity type selectively formed in the surface of the drift layer, a source layer of the first conductivity type selectively formed in the surface of the well layer, a trench formed to reach at least the inside of the drift layer from the surface of the source layer through the well layer, a buried electrode formed in the trench through a first insulating film, and a control electrode formed on the drift layer, the well layer, and the source layer through a second insulating film.
    Type: Grant
    Filed: February 3, 2004
    Date of Patent: June 27, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Ichiro Omura, Wataru Saito, Tsuneo Ogura, Hiromichi Ohashi, Yoshihiko Saito, Kenichi Tokano
  • Publication number: 20060108600
    Abstract: The present application provides a semiconductor device including a first-conductivity type semiconductor substrate, a pillar structure portion formed on the first-conductivity type semiconductor substrate and formed of five semiconductor pillar layers arranged in one direction parallel to a main surface of the first-conductivity type semiconductor substrate, and isolation insulating portions formed on the first-conductivity type semiconductor substrate and sandwiching the pillar structure portion between the isolation insulating portions, wherein the pillar structure portion is formed of a first first-conductivity type pillar layer, a second first-conductivity type pillar layer and a third first-conductivity type pillar layer which sandwich the first first-conductivity type pillar layer, a first second-conductivity type pillar layer provided between the first first-conductivity type pillar layer and the second first-conductivity type pillar layer, and a second second-conductivity type pillar layer provided b
    Type: Application
    Filed: November 3, 2005
    Publication date: May 25, 2006
    Inventors: Hideki Okumura, Hitoshi Kobayashi, Masanobu Tsuchitani, Satoshi Aida, Shigeo Kouzuki, Masaru Izumisawa, Satoshi Taji, Kenichi Tokano