Patents by Inventor Takashi Izumida

Takashi Izumida 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: 7662679
    Abstract: A method of manufacturing a semiconductor device includes forming a mask layer on a first-conductivity-type semiconductor substrate, etching the semiconductor substrate using the mask layer as a mask, thereby forming a projecting semiconductor layer, forming a first insulating layer on the semiconductor substrate to cover a lower portion of the projecting semiconductor layer, doping a first-conductivity-type impurity into the first insulating layer, thereby forming a high-impurity-concentration layer in the lower portion of the projecting semiconductor layer, forming gate insulating films on side surfaces of the projecting semiconductor layer which upwardly extend from an upper surface of the first insulating layer, and forming a gate electrode on the gate insulating films and on the first insulating film.
    Type: Grant
    Filed: August 15, 2005
    Date of Patent: February 16, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takashi Izumida, Sanae Ito, Takahisa Kanemura
  • Publication number: 20090289293
    Abstract: A semiconductor device of an example of the invention comprises a memory cell and a select gate transistor provided for the memory cell. A gate electrode of the select gate transistor has a Tri-gate structure in which an upper surface of a gate insulating film formed above a channel of the select gate transistor is set higher than a portion of an upper surface of an element isolation region of the select gate transistor.
    Type: Application
    Filed: May 21, 2009
    Publication date: November 26, 2009
    Inventors: Takashi IZUMIDA, Takahisa Kanemura, Nobutoshi Aoki
  • Publication number: 20090267155
    Abstract: A semiconductor device has a semiconductor substrate, a semiconductor fin which is formed on the semiconductor substrate, which has a long side direction and a short side direction, and which has a carbon-containing silicon film including an impurity and a silicon film formed on the carbon-containing silicon film, a gate electrode which is formed to face both side surfaces of the semiconductor fin in the short side direction, source and drain regions which are respectively formed in the semiconductor fin located in the direction of both sides in the long side direction of the semiconductor fin so as to sandwich the gate electrode, and an element isolation insulating film which is formed on the side surface of the semiconductor fin and between the gate electrode and the semiconductor substrate.
    Type: Application
    Filed: March 11, 2009
    Publication date: October 29, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Takashi IZUMIDA, Nobutoshi AOKI
  • Publication number: 20090152623
    Abstract: A fin transistor includes: a substrate; a plurality of semiconductor fins formed on the substrate; a gate electrode covering a channel region of the semiconductor fins; and a member as a stress source for the semiconductor fins included in a region of the gate electrode and the region provided between the semiconductor fins, and the member being made of a different material from the gate electrode.
    Type: Application
    Filed: December 16, 2008
    Publication date: June 18, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Masakazu GOTO, Nobutoshi AOKI, Takashi IZUMIDA, Kimitoshi OKANO, Satoshi INABA, Ichiro MIZUSHIMA
  • Publication number: 20090146203
    Abstract: In one aspect of the present invention, a nonvolatile semiconductor memory device may include a semiconductor substrate; a plurality of tunnel insulating films formed on the semiconductor substrate at predetermined intervals in a first direction; a plurality of floating gate electrodes each having a first portion and a second portion, the first portions being formed on the respective tunnel insulating films, the second portions being formed on the respective first portions and having smaller width than the first portions in the first direction; an inter-gate insulating film formed on the floating gate electrodes; and first and second control gate electrodes respectively formed on sidewalls, in the first direction, of the second portion of each of the plurality of floating gate electrodes with the inter-gate insulating film interposed therebetween.
    Type: Application
    Filed: December 3, 2008
    Publication date: June 11, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Takashi Izumida, Masaki Kondo
  • Patent number: 7535064
    Abstract: A semiconductor device includes a Fin, a source region and a drain region, a first extension region, a second extension region and a channel region. The Fin is formed on a major surface of a semiconductor substrate. The source region and drain region are formed at both end portions of the Fin. The first extension region is formed between the source region and the drain region within the Fin in contact with the source region. The second extension region is formed between the source region and the drain region within the Fin in contact with the drain region. The channel region is located between the first extension region and the second extension region within the Fin, a height of the Fin of the channel region being greater than a height of the Fin of each of the first extension region and the second extension region.
    Type: Grant
    Filed: April 12, 2006
    Date of Patent: May 19, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Takashi Izumida
  • Publication number: 20090101959
    Abstract: According to an aspect of the present invention, there is provided a nonvolatile semiconductor memory device including: a semiconductor substrate; memory cell transistors that are series-connected; and a select transistor that includes: a first diffusion region that is formed in the semiconductor substrate at one end of the memory cell transistors; a first insulating film that is formed on the semiconductor substrate at a side of the first diffusion region; a select gate electrode that is formed on the first insulating film; a semiconductor pillar that is formed to extend upward from the semiconductor substrate and to be separated from the select gate electrode; a second insulating film that is formed between the select gate electrode and the semiconductor pillar; and a second diffusion region that is formed on the semiconductor pillar.
    Type: Application
    Filed: October 9, 2008
    Publication date: April 23, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Takahisa KANEMURA, Takashi Izumida, Nobutoshi Aoki
  • Publication number: 20090101960
    Abstract: According to an aspect of the present invention, there is provided a semiconductor memory device including: a semiconductor substrate having: a contact region; a select gate region; and a memory cell region; a first element isolation region formed in the contact region and having a first depth; a second element isolation region formed in the select gate region and having a second depth; and a third element isolation region formed in the memory cell region and having a third depth which is smaller than the first depth.
    Type: Application
    Filed: October 9, 2008
    Publication date: April 23, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Nobutoshi AOKI, Takashi Izumida, Masaki Kondo, Fumitaka Arai
  • Publication number: 20090065869
    Abstract: A semiconductor device has a plurality of fins formed on a semiconductor substrate to be separated from each other, a first contact region which connects commonly one end side of the plurality of fins, a second contact region which connects commonly the other end side of the plurality of fins, a gate electrode arranged to be opposed to at least both side surfaces of the plurality of fins by sandwiching a gate insulating film therebetween, a source electrode including the first contact region and the plurality of fins on a side closer to the first contact region than the gate electrode, and a drain electrode including the second contact region and the plurality of fins on a side closer to the second contact than the gate electrode. The ratio Rd/Rs of a resistance Rd of each fin in the drain region to a resistance Rs of each fin in the source region is larger than 1.
    Type: Application
    Filed: September 9, 2008
    Publication date: March 12, 2009
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Tatsuya OHGURO, Takashi IZUMIDA, Satoshi INABA, Kimitoshi OKANO, Nobutoshi AOKI
  • Patent number: 7473964
    Abstract: A semiconductor device includes: an insulating layer; a semiconductor fin protruding from the insulating layer, extending in a first direction parallel to a major surface of the insulating layer, and having a source region, a channel section, and a drain region arranged in the first direction; a gate electrode opposed at least to a side face of the channel section in the semiconductor fin and extending in a second direction that is substantially orthogonal to the first direction and parallel to the major surface of the insulating layer; an insulating film interposed between the semiconductor fin and the gate electrode; a spacer layer provided on the channel section; a sidewall insulating layer provided adjacent to a side face of the spacer layer substantially parallel to the second direction; and a stress liner. The stress liner covers the sidewall insulating layer and the spacer layer and has an intrinsic stress for distorting the semiconductor fin.
    Type: Grant
    Filed: March 5, 2007
    Date of Patent: January 6, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Takashi Izumida
  • Publication number: 20080251854
    Abstract: In one aspect of the present invention, semiconductor device, may include a p-channel semiconductor active region, an n-channel semiconductor active region, an element isolation insulating layer which electrically isolates the p-channel semiconductor active region from the n-channel semiconductor active region, and an insulating layer made of a material different from that of the element isolation insulating layer, and being in contact with both ends, in its channel length direction, of the p-channel semiconductor active region to apply a compression stress in the channel length direction to a channel of the p-channel semiconductor active region, wherein the p-channel semiconductor active region is surrounded by the insulating layer, which is in contact with the both ends, in the channel length direction, of the p-channel semiconductor active region, and the p-channel semiconductor active region is surrounded by the element isolation insulating layer, which is in contact with the side surfaces, approximately
    Type: Application
    Filed: April 10, 2008
    Publication date: October 16, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yoshiaki SHIMOOKA, Takashi IZUMIDA, Hiroki OKAMOTO
  • Publication number: 20080246072
    Abstract: In a nonvolatile semiconductor memory device including a memory cell column formed by connecting in series a plurality of memory cells each having a structure in which a charge-storage layer and a control gate are stacked via an insulating layer on a semiconductor substrate, a first selection transistor formed on the semiconductor substrate and connected between one end of the memory cell column and a common source line, and a second selection transistor formed on the semiconductor substrate and connected between the other end of the memory cell column and a bit line, a recessed portion is formed on a surface of the semiconductor substrate between the first selection transistor and a memory cell adjacent to the first selection transistor, and an edge at a side of the first selection transistor in the recessed portion reaches an end portion at a side of the memory cell in a gate of the first selection transistor.
    Type: Application
    Filed: July 5, 2007
    Publication date: October 9, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Masaki Kondo, Takashi Izumida, Nobutoshi Aoki, Toshiharu Watanabe
  • Publication number: 20080179659
    Abstract: A nonvolatile semiconductor memory device relating to one embodiment of this invention includes a substrate, a plurality of memory strings formed on said substrate, said memory string having a first select gate transistor, a plurality of memory cells and a second select gate transistor, said first select gate transistor having a first pillar semiconductor, a first gate insulation layer formed around said first pillar semiconductor and a first gate electrode being formed around said first gate insulation layer; said memory cell having a second pillar semiconductor, a first insulation layer formed around said second pillar semiconductor, a storage layer formed around said first insulation layer, a second insulation layer formed around said storage layer and first to nth electrodes (n is a natural number 2 or more) being formed around said second insulation layer, said first to nth electrodes being spread in two dimensions respectively, said second select gate transistor having a third pillar semiconductor, a se
    Type: Application
    Filed: January 28, 2008
    Publication date: July 31, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Toshiyuki Enda, Hiroyoshi Tanimoto, Takashi Izumida
  • Publication number: 20070210355
    Abstract: A semiconductor device includes: an insulating layer; a semiconductor fin protruding from the insulating layer, extending in a first direction parallel to a major surface of the insulating layer, and having a source region, a channel section, and a drain region arranged in the first direction; a gate electrode opposed at least to a side face of the channel section in the semiconductor fin and extending in a second direction that is substantially orthogonal to the first direction and parallel to the major surface of the insulating layer; an insulating film interposed between the semiconductor fin and the gate electrode; a spacer layer provided on the channel section; a sidewall insulating layer provided adjacent to a side face of the spacer layer substantially parallel to the second direction; and a stress liner. The stress liner covers the sidewall insulating layer and the spacer layer and has an intrinsic stress for distorting the semiconductor fin.
    Type: Application
    Filed: March 5, 2007
    Publication date: September 13, 2007
    Inventor: Takashi Izumida
  • Publication number: 20070170509
    Abstract: A semiconductor device includes a Fin, a source region and a drain region, a first extension region, a second extension region and a channel region. The Fin is formed on a major surface of a semiconductor substrate. The source region and drain region are formed at both end portions of the Fin. The first extension region is formed between the source region and the drain region within the Fin in contact with the source region. The second extension region is formed between the source region and the drain region within the Fin in contact with the drain region. The channel region is located between the first extension region and the second extension region within the Fin, a height of the Fin of the channel region being greater than a height of the Fin of each of the first extension region and the second extension region.
    Type: Application
    Filed: April 12, 2006
    Publication date: July 26, 2007
    Inventor: Takashi Izumida
  • Publication number: 20070158720
    Abstract: A semiconductor device includes a semiconductor substrate, at least one trench capacitor which is buried into the surface area of the semiconductor substrate, and a first insulation film which is formed on the trench capacitor. The semiconductor device further includes at least one switching transistor provided on the surface of the semiconductor substrate which corresponds to the trench capacitor, the switching transistor having a body section set in an electrically floating state between source and drain regions, the first insulation film being interposed between the body section of the switching transistor and the trench capacitor opposed to one another, the trench capacitor being electrically connected to one of the source and drain regions of the switching transistor.
    Type: Application
    Filed: April 24, 2006
    Publication date: July 12, 2007
    Inventor: Takashi Izumida
  • Publication number: 20070063224
    Abstract: A semiconductor device includes a fin-shaped semiconductor layer, a gate electrode section formed in a widthwise direction of the semiconductor layer with a gate insulation film interposed therebetween, the gate electrode section including a plurality of electrode materials having different work functions and stacked one another, and a channel section formed adjacent to the gate insulation film in the semiconductor layer. The semiconductor device further includes source and drain regions formed adjacent to the channel section.
    Type: Application
    Filed: July 31, 2006
    Publication date: March 22, 2007
    Inventors: Takeshi Watanabe, Kimitoshi Okano, Takashi Izumida
  • Publication number: 20060244051
    Abstract: A method of manufacturing a semiconductor device includes forming a mask layer on a first-conductivity-type semiconductor substrate, etching the semiconductor substrate using the mask layer as a mask, thereby forming a projecting semiconductor layer, forming a first insulating layer on the semiconductor substrate to cover a lower portion of the projecting semiconductor layer, doping a first-conductivity-type impurity into the first insulating layer, thereby forming a high-impurity-concentration layer in the lower portion of the projecting semiconductor layer, forming gate insulating films on side surfaces of the projecting semiconductor layer which upwardly extend from an upper surface of the first insulating layer, and forming a gate electrode on the gate insulating films and on the first insulating film.
    Type: Application
    Filed: August 15, 2005
    Publication date: November 2, 2006
    Inventors: Takashi Izumida, Sanae Ito, Takahisa Kanemura
  • Patent number: 7115476
    Abstract: A method of manufacturing a semiconductor device includes forming a mask layer on a semiconductor substrate, etching the semiconductor substrate using the mask layer as a mask, thereby forming a semiconductor pillar, doping an impurity into the semiconductor substrate, thereby forming a first source/drain region in part of the semiconductor substrate, which is located under the semiconductor pillar, forming a gate insulating film on the semiconductor substrate, which contacts a side surface of the semiconductor pillar, forming a gate electrode on a side surface of the gate insulating film, forming a first insulating layer on the gate electrode, which contacts a side surface of the semiconductor pillar, and doping the impurity into the first insulating layer, thereby forming a second source/drain region in part of the semiconductor pillar, which is located on a side surface of the first insulating layer.
    Type: Grant
    Filed: August 11, 2005
    Date of Patent: October 3, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Takashi Izumida