Patents by Inventor Wataru Sakamoto

Wataru Sakamoto 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: 20160079253
    Abstract: A semiconductor device according to an embodiment includes two semiconductor pillars, a connection member connected between the two semiconductor pillars, and a contact connected to the connection member. There is not a conductive member disposed between the two semiconductor pillars.
    Type: Application
    Filed: March 11, 2015
    Publication date: March 17, 2016
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Mikiko MORI, Ryota SUZUKI, Tatsuya KATO, Wataru SAKAMOTO, Fumie KIKUSHIMA
  • Publication number: 20160071863
    Abstract: A method of manufacturing a semiconductor storage apparatus according to an embodiment includes forming an array of a plurality of memory cells. The method includes forming an interlayer insulating film that covers the memory cells. The method includes forming a first nitride film that covers an upper part of the interlayer insulating film. The method includes ion-implanting a first impurity into the first nitride film.
    Type: Application
    Filed: March 4, 2015
    Publication date: March 10, 2016
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Akio KANEKO, Wataru SAKAMOTO, Takeshi MURATA
  • Patent number: 9257443
    Abstract: According to an embodiment, a semiconductor memory device includes a semiconductor pillar, a first electrode film, a second electrode film, a first insulating film, a second insulating film, and a wiring film. The semiconductor member is extending in a first direction. The first electrode film is disposed at the lateral side of the semiconductor member away from the semiconductor member. The second electrode film is provided between the semiconductor member and the first electrode film. The first insulating film is provided between the semiconductor member and the second electrode film. The second insulating film is provided between the second electrode film and the first electrode film. The wiring film is disposed in a wiring lead-out region adjacent to the memory cell region. And the first electrode film is formed of a material different from a material of the wiring film, and being electrically connected to the wiring film.
    Type: Grant
    Filed: January 16, 2015
    Date of Patent: February 9, 2016
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Fumie Kikushima, Tatsuya Kato, Wataru Sakamoto, Fumitaka Arai
  • Publication number: 20160020225
    Abstract: A nonvolatile semiconductor memory device includes a plurality of memory strings including a plurality of memory transistors connected in series and a selection transistor disposed on either end of the plurality of memory transistors, which together form a memory cell. The memory transistors and the selection transistors each include a polysilicon layer formed on an insulating film as a channel region thereof. A drain region is in a first diffusion layer region in the polysilicon layer in a location adjacent to a selection transistor at a first end of the memory string, and a source region is in a second diffusion layer region in the polysilicon layer in a location adjacent to a selection transistor at a second end of the memory string. In at least one of the first and the second diffusion regions, the grain size of the polysilicon is smaller than in other portions of the polysilicon.
    Type: Application
    Filed: February 26, 2015
    Publication date: January 21, 2016
    Inventors: Wataru SAKAMOTO, Kenta YAMADA
  • Publication number: 20150263027
    Abstract: A nonvolatile semiconductor storage device is provided with a semiconductor substrate; a tunnel insulating film formed above the semiconductor substrate; a charge storing layer formed above the tunnel insulating film; a charge storing surface layer film being formed only above an upper surface of the charge storing layer and being provided with a metal film or a metal containing film having a work function higher than a work function of an n-type polysilicon (Si); an interelectrode insulating film being formed above the charge storing surface layer film and being provided with a laminate film being provided with either one of a silicon oxide film, a silicon nitride film, and a silicon oxynitride film, or being provided with two or more of the silicon oxide film, the silicon nitride film, and the silicon oxynitride film; and a control electrode formed above the interelectrode insulating film.
    Type: Application
    Filed: September 11, 2014
    Publication date: September 17, 2015
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Wataru SAKAMOTO
  • Publication number: 20150200199
    Abstract: According to one embodiment, a semiconductor memory device includes a substrate, a semiconductor pillar provided on the substrate to extend in a vertical direction, a plurality of first electrode films provided sideward of the semiconductor pillar to extend in a first direction. The plurality of first electrode films are disposed to be separated from each other along the vertical direction. The semiconductor memory device further includes a plurality of second electrode films provided between the semiconductor pillar and the first electrode films. The plurality of second electrode films are disposed to be separated from each other along the vertical direction. The semiconductor memory device further includes a first insulating film provided between the semiconductor pillar and the second electrode films, and a second insulating film provided between the second electrode film and the first electrode film.
    Type: Application
    Filed: March 11, 2014
    Publication date: July 16, 2015
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Wataru SAKAMOTO, Ryota Suzuki, Tatsuya Okamoto, Tatsuya Kato
  • Patent number: 9029933
    Abstract: According to an embodiment, a non-volatile memory device includes a memory cell including a semiconductor layer, a charge storage layer provided on the semiconductor layer, and a first insulating film provided between the semiconductor layer and the charge storage layer. The device also includes a first conductive layer provided on the charge storage layer, a second conductive layer provided between the charge storage layer and the first conductive layer, a second insulating film provided between the charge storage layer and the second conductive layer, and a third insulating film provided between the first conductive layer and the second conductive layer.
    Type: Grant
    Filed: September 5, 2013
    Date of Patent: May 12, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shinichi Sotome, Kenta Yamada, Wataru Sakamoto
  • Patent number: 9007846
    Abstract: According to one embodiment, there is provided a non-volatile semiconductor storage device including a memory cell and a control unit. The memory cell has a gate electrode including a control gate and a charge storage region on a semiconductor substrate and has a channel region under the gate electrode in the semiconductor substrate. The control unit, during an erase operation where electric charges written in the charge storage region are extracted to the channel region, periodically varies a voltage which is to be applied between the control gate and the channel region.
    Type: Grant
    Filed: February 4, 2013
    Date of Patent: April 14, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akio Kaneko, Wataru Sakamoto
  • Patent number: 8994090
    Abstract: A nonvolatile semiconductor storage device including a memory cell region including a memory cell having a charge storing layer above a gate insulating film and a control electrode above the charge storing layer via an interelectrode insulating film; and a peripheral circuit region including a peripheral element having a first polysilicon and a first insulating film above the first polysilicon; wherein the charge storing layer includes a polysilicon doped with P-type impurity including a first upper region contacting the interelectrode insulating film and having a first doped layer doped with carbon or nitrogen, and at least a portion of a region below the first doped layer is neither doped with carbon nor nitrogen, and wherein the first polysilicon includes a second upper region contacting the first insulating film and having a second doped layer doped with carbon or nitrogen, the first and the second doped layers having equal thickness.
    Type: Grant
    Filed: September 12, 2013
    Date of Patent: March 31, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Wataru Sakamoto, Kazuma Takahashi, Hideto Takekida
  • Publication number: 20150076578
    Abstract: A nonvolatile semiconductor storage device is provided with a memory-cell region; a peripheral-circuit region disposed adjacent to the memory-cell region a first memory-cell unit disposed in a first layer located in the memory-cell region; a second memory-cell unit disposed in a k-th layer of the memory-cell region where k is an integer equal to or greater than 2, the second memory-cell unit having an element region extending in a first direction and having a first width in a second direction crossing the first direction; and a peripheral-circuit element disposed in the first layer located in the peripheral-circuit region. Two or more dummy element each having a second width 2n+1 times greater than the first width in the second direction are disposed in the k-th layer located in the peripheral-circuit region where n is an integer equal to or greater than 0.
    Type: Application
    Filed: May 30, 2014
    Publication date: March 19, 2015
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Wataru SAKAMOTO, Kenta YAMADA
  • Publication number: 20150060995
    Abstract: Nonvolatile semiconductor storage device provided with first to fourth memory-cell unit each including a first select transistor, a second select transistor series connected to the first select transistor, a third select transistor, and memory-cell transistors series connected between the first and the second select transistors and the third select transistor. The memory-cell transistors have a stack structure including a charge storing layer and a control electrode above the charge storing layer via an insulating film. The first to third select transistors each has a stack structure substantially identical to the aforementioned stack structure. Threshold voltages of the first select transistors in the first and the fourth memory-cell unit and the second transistors in the second and third memory-cell unit differ from the threshold voltages of the second select transistors in the first and the fourth memory-cell unit and the first select transistors in the second and third memory-cell unit.
    Type: Application
    Filed: September 2, 2014
    Publication date: March 5, 2015
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Wataru SAKAMOTO, Ryota Suzuki
  • Patent number: 8969941
    Abstract: According to an embodiment, a semiconductor device, includes a semiconductor substrate, first and second transistors. The first transistor includes a first insulating film provided on the semiconductor substrate, a first conductive film provided on the first insulating film, a second insulating film provided on the first conductive film, and a second conductive film provided on the second insulating film. The second transistor is provided to be separated from the first transistor, the second transistor including a third insulating film provided on the semiconductor substrate, a third conductive film provided on the third insulating film, a fourth insulating film provided on the third conductive film, and a fourth conductive film provided on the fourth insulating film. The third conductive film is thicker than the first conductive film, and the second transistor has a through-portion piercing the fourth insulating film to connect the third conductive film and the fourth conductive film.
    Type: Grant
    Filed: February 21, 2013
    Date of Patent: March 3, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Wataru Sakamoto
  • Patent number: 8957469
    Abstract: A semiconductor storage device according to an embodiment comprises a memory cell string in which a plurality of memory cells each having a gate are serially connected to each other. A selective transistor is connected to an end memory cell at an end of the memory cell string. A sidewall film covers a side surface of a gate of the end memory cell and a side surface of a gate of the selective transistor between the end memory cell and the selective transistor. An air gap is provided between the sidewall film of the end memory cell and the sidewall film of the selective transistor.
    Type: Grant
    Filed: February 21, 2012
    Date of Patent: February 17, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Ryosuke Isomura, Wataru Sakamoto, Hiroyuki Nitta
  • Publication number: 20140332816
    Abstract: A semiconductor device includes a first insulating film formed on a memory cell region of the semiconductor substrate, a first polysilicon layer formed on the first insulating film, and memory cell transistors formed on the first polysilicon layer, each including a charge storage layer, an inter-electrode insulating film and a control gate electrode. The semiconductor device further includes a laminated structure formed on a peripheral circuit region of the semiconductor substrate that includes a second insulating film, a second polysilicon layer, a third insulating film, a third polysilicon layer, a fourth insulating film formed from the same material as a material of the inter-electrode insulating film, and a first electrode formed from the same material as a material of the control gate electrode. The third polysilicon layer, the fourth insulating film, and the first electrode are arranged in the peripheral circuit region to form a capacitance element.
    Type: Application
    Filed: February 7, 2014
    Publication date: November 13, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Wataru SAKAMOTO
  • Publication number: 20140264537
    Abstract: A nonvolatile semiconductor storage device including a memory cell region including a memory cell having a charge storing layer above a gate insulating film and a control electrode above the charge storing layer via an interelectrode insulating film; and a peripheral circuit region including a peripheral element having a first polysilicon and a first insulating film above the first polysilicon; wherein the charge storing layer includes a polysilicon doped with P-type impurity including a first upper region contacting the interelectrode insulating film and having a first doped layer doped with carbon or nitrogen, and at least a portion of a region below the first doped layer is neither doped with carbon nor nitrogen, and wherein the first polysilicon includes a second upper region contacting the first insulating film and having a second doped layer doped with carbon or nitrogen, the first and the second doped layers having equal thickness.
    Type: Application
    Filed: September 12, 2013
    Publication date: September 18, 2014
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Wataru SAKAMOTO, Kazuma Takahashi, Hideto Takekida
  • Patent number: 8837223
    Abstract: A nonvolatile semiconductor memory device according to an embodiment includes: a memory cell array in which a plurality of NAND cell units are arranged, the NAND cell units including a plurality of memory cells, and select gate transistors, the memory cell including a semiconductor layer, a gate insulating film, a charge accumulation layer, and a control gate; and a control circuit. The control circuit adjusts a write condition of each of the memory cells in accordance with write data to each of the memory cells and memory cells adjacent to the memory cells within the data to be written.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: September 16, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Wataru Sakamoto, Fumitaka Arai, Takashi Kobayashi, Ken Komiya, Shinichi Sotome, Tatsuya Kato
  • Patent number: 8755228
    Abstract: According to one embodiment, there is provided a writing method. The method includes setting potentials of a plurality of word lines to a first potential. The first potential is a potential to allow memory cells corresponding to a selective bit line to be in on state. The method also includes setting potentials of non-adjacent word lines to a second potential while maintaining potentials of adjacent word lines at a potential which allows the memory cells corresponding to the selective bit line to be in on state and setting a potential of a selective word line to a third potential. The second potential is a potential which is determined so as to allow the memory cells corresponding to the selective bit line to be in off state. The third potential is a potential where data is written in the selective memory cell corresponding to the selective bit line.
    Type: Grant
    Filed: February 6, 2013
    Date of Patent: June 17, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akio Kaneko, Wataru Sakamoto
  • Publication number: 20140070305
    Abstract: According to an embodiment, a non-volatile memory device includes a memory cell including a semiconductor layer, a charge storage layer provided on the semiconductor layer, and a first insulating film provided between the semiconductor layer and the charge storage layer. The device also includes a first conductive layer provided on the charge storage layer, a second conductive layer provided between the charge storage layer and the first conductive layer, a second insulating film provided between the charge storage layer and the second conductive layer, and a third insulating film provided between the first conductive layer and the second conductive layer.
    Type: Application
    Filed: September 5, 2013
    Publication date: March 13, 2014
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Shinichi SOTOME, Kenta Yamada, Wataru Sakamoto
  • Publication number: 20140071759
    Abstract: According to an embodiment, a nonvolatile memory device includes a plurality of memory cell strings disposed in parallel in a first direction, a bit line and a first contact plug. Each of the memory cell strings extends in a second direction orthogonal to the first direction and includes a plurality of memory cells disposed in parallel in the second direction. The bit line is shared by two adjacent memory cell strings of the memory cell strings, and the first contact plug is connected to the bit line and one of the two adjacent memory cell strings. The bit line includes a first transistor section controlling a current flowing in the one of the adjacent memory cell strings.
    Type: Application
    Filed: February 22, 2013
    Publication date: March 13, 2014
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Fumito NOMURA, Hideto Takekida, Wataru Sakamoto
  • Publication number: 20140043917
    Abstract: According to one embodiment, there is provided a non-volatile semiconductor storage device including a memory cell and a control unit. The memory cell has a gate electrode including a control gate and a charge storage region on a semiconductor substrate and has a channel region under the gate electrode in the semiconductor substrate. The control unit, during an erase operation where electric charges written in the charge storage region are extracted to the channel region, periodically varies a voltage which is to be applied between the control gate and the channel region.
    Type: Application
    Filed: February 4, 2013
    Publication date: February 13, 2014
    Applicant: Kabushiki Kaisha Toshiba Corporation
    Inventors: Akio KANEKO, Wataru Sakamoto