Patents by Inventor Tomoko Fujiwara

Tomoko Fujiwara 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: 8766446
    Abstract: A semiconductor memory device comprising a stacked unit, a semiconductor pillar, a charge storage layer, and a non-insulating film. The stacked unit includes first conductive layers and first insulating layers which are stacked alternately. The semiconductor pillar passes through the stacked body and the semiconductor pillar has a tubular structure. The charge storage layer is provided between the semiconductor pillar and each of the first conductive layers. The non-insulating film is provided inside the tubular structure and has a non-insulating member. The first effective impurity concentration of the non-insulating film is lower than a second effective impurity concentration of the semiconductor pillar.
    Type: Grant
    Filed: August 30, 2012
    Date of Patent: July 1, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Nobuhito Kuge, Naoki Yasuda, Yoshiaki Fukuzumi, Tomoko Fujiwara
  • Patent number: 8766351
    Abstract: According to one embodiment, a columnar semiconductor, a floating gate electrode formed on a side surface of the columnar semiconductor via a tunnel dielectric film, and a control gate electrode formed to surround the floating gate electrode via a block dielectric film are provided.
    Type: Grant
    Filed: May 20, 2011
    Date of Patent: July 1, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takeshi Imamura, Yoshiaki Fukuzumi, Hideaki Aochi, Masaru Kito, Tomoko Fujiwara, Kaori Kawasaki, Ryouhei Kirisawa
  • Patent number: 8767452
    Abstract: According to one embodiment, a semiconductor memory device includes a stacked body, a semiconductor pillar, a charge storage layer, a tunneling layer, a dividing trench and a first heating unit. The stacked body includes a plurality of first insulating films stacked alternately with a plurality of electrode films. The semiconductor pillar pierces the stacked body. The charge storage layer is provided between the electrode films and the semiconductor pillar. The tunneling layer is provided between the charge storage layer and the semiconductor pillar. The dividing trench is provided between the semiconductor pillars in one direction orthogonal to a stacking direction of the stacked body to divide the electrode films. The first heating unit is provided in an interior of the dividing trench.
    Type: Grant
    Filed: March 13, 2012
    Date of Patent: July 1, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masaru Kito, Tomoko Fujiwara, Hideaki Aochi
  • Patent number: 8760924
    Abstract: A memory cell comprises a first semiconductor layer, and a first conductive layer. The first semiconductor layer extends in a perpendicular direction with respect to a semiconductor substrate. The first conductive layer sandwiches a charge storage layer with the first semiconductor layer. A control circuit executes a first program operation and then executes a second program operation. The first program operation supplies a first voltage to the body of the memory cell and supplies a second voltage larger than the first voltage to the gate of the memory cell. The second program operation renders the body of the memory cell in a floating state and supplies a third voltage which is positive to the gate of the memory cell.
    Type: Grant
    Filed: March 22, 2012
    Date of Patent: June 24, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hitoshi Iwai, Tomoko Fujiwara, Hideaki Aochi, Masaru Kito
  • Patent number: 8748971
    Abstract: A nonvolatile semiconductor memory device includes: a semiconductor substrate; a stacked body provided on the semiconductor substrate, the stacked body having electrode films and insulating films being alternately stacked; a first and second semiconductor pillars; and a first and second charge storage layers. The first and second semiconductor pillars are provided inside a through hole penetrating through the stacked body in a stacking direction of the stacked body. The through hole has a cross section of an oblate circle, when cutting in a direction perpendicular to the stacking direction. The first and second semiconductor pillars face each other in a major axis direction of the first oblate circle. The first and second semiconductor pillars extend in the stacking direction. The first and second charge storage layers are provided between the electrode film and the first and second semiconductor pillars, respectively.
    Type: Grant
    Filed: April 5, 2013
    Date of Patent: June 10, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroyasu Tanaka, Hideaki Aochi, Ryota Katsumata, Masaru Kidoh, Masaru Kito, Yoshiaki Fukuzumi, Yosuke Komori, Megumi Ishiduki, Tomoko Fujiwara, Junya Matsunami, Ryouhei Kirisawa
  • Publication number: 20140117434
    Abstract: A nonvolatile semiconductor memory device, includes: a stacked structural unit including a plurality of insulating films alternately stacked with a plurality of electrode films in a first direction; a selection gate electrode stacked on the stacked structural unit in the first direction; an insulating layer stacked on the selection gate electrode in the first direction; a first semiconductor pillar piercing the stacked structural unit, the selection gate electrode, and the insulating layer in the first direction, a first cross section of the first semiconductor pillar having an annular configuration, the first cross section being cut in a plane orthogonal to the first direction; a first core unit buried in an inner side of the first semiconductor pillar, the first core unit being recessed from an upper face of the insulating layer; and a first conducting layer of the first semiconductor pillar provided on the first core unit to contact the first core unit.
    Type: Application
    Filed: January 8, 2014
    Publication date: May 1, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yoshiaki Fukuzumi, Ryota Katsumata, Masaru Kito, Masaru Kidoh, Hiroyasu Tanaka, Yosuke Komori, Megumi Ishiduki, Junya Matsunami, Tomoko Fujiwara, Hideaki Aochi, Ryouhei Kirisawa, Yoshimasa Mikajiri, Shigeto Oota
  • Patent number: 8654586
    Abstract: A nonvolatile semiconductor memory device includes a memory unit and a control unit. The memory unit includes a multilayer structure including electrode films and inter-electrode insulating films alternately stacked in a first direction; a semiconductor pillar piercing the multilayer structure in the first direction; a memory layer provided between the semiconductor pillar and the electrode films; an inner insulating film provided between the memory layer and the semiconductor pillar; an outer insulating film provided between the memory layer and the electrode films; and a wiring electrically connected to the first semiconductor pillar. In an erasing operation, the control unit sets the first wiring at a first potential and sets the electrode film at a second potential lower than the first potential, and then sets the first wiring at a third potential and sets the electrode film at a fourth potential higher than the third potential.
    Type: Grant
    Filed: January 9, 2013
    Date of Patent: February 18, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masaru Kito, Ryota Katsumata, Yoshiaki Fukuzumi, Masaru Kidoh, Hiroyasu Tanaka, Yosuke Komori, Megumi Ishiduki, Junya Matsunami, Tomoko Fujiwara, Hideaki Aochi, Ryouhei Kirisawa, Yoshimasa Mikajiri, Shigeto Oota
  • Patent number: 8653582
    Abstract: A nonvolatile semiconductor memory device, includes: a stacked structural unit including a plurality of insulating films alternately stacked with a plurality of electrode films in a first direction; a selection gate electrode stacked on the stacked structural unit in the first direction; an insulating layer stacked on the selection gate electrode in the first direction; a first semiconductor pillar piercing the stacked structural unit, the selection gate electrode, and the insulating layer in the first direction, a first cross section of the first semiconductor pillar having an annular configuration, the first cross section being cut in a plane orthogonal to the first direction; a first core unit buried in an inner side of the first semiconductor pillar, the first core unit being recessed from an upper face of the insulating layer; and a first conducting layer of the first semiconductor pillar provided on the first core unit to contact the first core unit.
    Type: Grant
    Filed: March 16, 2010
    Date of Patent: February 18, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki Fukuzumi, Ryota Katsumata, Masaru Kito, Masaru Kidoh, Hiroyasu Tanaka, Yosuke Komori, Megumi Ishiduki, Junya Matsunami, Tomoko Fujiwara, Hideaki Aochi, Ryouhei Kirisawa, Yoshimasa Mikajiri, Shigeto Oota
  • Patent number: 8643081
    Abstract: According to one embodiment, a semiconductor memory device comprises a first layer, a first conductive layer, a insulating layer, and a second conductive layer stacked on a substrate, a block insulating layer on inner surfaces of a pair of through-holes formed in the first conductive layer, the insulating layer, and the second conductive layer, and on an inner surface of a connecting hole connecting lower ends of the pair of through-holes, a charge storage layer on the block insulating layer, a second layer on the charge storage layer, and a semiconductor layer on the second layer. The second layer includes an air gap layer on the charge storage layer in the pair of through-holes, and a third conductive layer on the charge storage layer in the connecting hole.
    Type: Grant
    Filed: September 5, 2012
    Date of Patent: February 4, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomoko Fujiwara, Yoshiaki Fukuzumi, Hideaki Aochi
  • Patent number: 8629492
    Abstract: In one embodiment, a shift register memory includes a substrate, and a channel layer provided on the substrate, and having a helical shape rotating around an axis which is perpendicular to a surface of the substrate. The memory further includes at least three control electrodes provided on the substrate, extending in a direction parallel to the axis, and to be used to transfer charges in the channel layer.
    Type: Grant
    Filed: February 27, 2012
    Date of Patent: January 14, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki Fukuzumi, Hideaki Aochi, Tomoko Fujiwara
  • Patent number: 8598643
    Abstract: According to one embodiment, a nonvolatile semiconductor memory device comprises a first conductive layer, a second conductive layer, a first inter-electrode insulating film, and a third conductive layer stacked above the first conductive layer, a memory film, a semiconductor layer, an insulating member, and a silicide layer. The memory film and the semiconductor layer is formed on the inner surface of through hole provided in the second conductive layer, the first inter-electrode insulating film, and the third conductive layer. The insulating member is buried in a slit dividing the second conductive layer, the first inter-electrode insulating film, and the third conductive layer. The silicide layer is formed on surfaces of the second conductive layer and the third conductive layer in the slit. The distance between the second conductive layer and the third conductive layer along the inner surface of the slit is longer than that of along the stacking direction.
    Type: Grant
    Filed: September 18, 2011
    Date of Patent: December 3, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kaori Kawasaki, Yoshiaki Fukuzumi, Masaru Kito, Tomoko Fujiwara, Takeshi Imamura, Ryouhei Kirisawa, Hideaki Aochi
  • Patent number: 8541866
    Abstract: A nonvolatile semiconductor memory device, includes: a stacked structural unit including a plurality of stacked component units stacked in a first direction, each of the stacked component units including a first conducting film made of a semiconductor of a first conductivity type provided perpendicular to the first direction and a first insulating film stacked in the first direction with the first conducting film; a semiconductor pillar piercing the stacked structural unit in the first direction and including a conducting region of a second conductivity type, the semiconductor pillar including a first region opposing each of the first conducting films, and a second region provided between the first regions with respect to the first direction, the second region having a resistance different from a resistance of the first region; and a second insulating film provided between the semiconductor pillar and the first conducting film.
    Type: Grant
    Filed: March 12, 2010
    Date of Patent: September 24, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Ryota Katsumata, Masaru Kito, Yoshiaki Fukuzumi, Masaru Kidoh, Hiroyasu Tanaka, Yosuke Komori, Megumi Ishiduki, Hideaki Aochi, Ryouhei Kirisawa, Junya Matsunami, Tomoko Fujiwara
  • Publication number: 20130234233
    Abstract: According to one embodiment, a semiconductor memory device comprises a first layer, a first conductive layer, a insulating layer, and a second conductive layer stacked on a substrate, a block insulating layer on inner surfaces of a pair of through-holes formed in the first conductive layer, the insulating layer, and the second conductive layer, and on an inner surface of a connecting hole connecting lower ends of the pair of through-holes, a charge storage layer on the block insulating layer, a second layer on the charge storage layer, and a semiconductor layer on the second layer. The second layer includes an air gap layer on the charge storage layer in the pair of through-holes, and a third conductive layer on the charge storage layer in the connecting hole.
    Type: Application
    Filed: September 5, 2012
    Publication date: September 12, 2013
    Inventors: Tomoko FUJIWARA, Yoshiaki FUKUZUMI, Hideaki AOCHI
  • Publication number: 20130228928
    Abstract: According to one embodiment, a semiconductor device includes a stacked body, a second conductive layer, a second insulating layer, a tubular semiconductor pillar, an insulating film and an occlusion film. The second conductive layer is provided on the stacked body. The second insulating layer is provided on the second conductive layer. The tubular semiconductor pillar is provided in such a manner as to pass through the second insulating layer, the second conductive layer and the stacked body. The insulating film is provided between the semiconductor pillar, and the second insulating layer, the second conductive layer and the stacked body. The occlusion film occludes the tube in a lower portion of the portion passing through the second insulating layer in the semiconductor pillar. The tube below the occlusion film in the semiconductor pillar is an air gap.
    Type: Application
    Filed: August 30, 2012
    Publication date: September 5, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Nobuhito KUGE, Naoki Yasuda, Yoshiaki Fukuzumi, Tomoko Fujiwara
  • Publication number: 20130228850
    Abstract: A nonvolatile semiconductor memory device includes: a semiconductor substrate; a stacked body provided on the semiconductor substrate, the stacked body having electrode films and insulating films being alternately stacked; a first and second semiconductor pillars; and a first and second charge storage layers. The first and second semiconductor pillars are provided inside a through hole penetrating through the stacked body in a stacking direction of the stacked body. The through hole has a cross section of an oblate circle, when cutting in a direction perpendicular to the stacking direction. The first and second semiconductor pillars face each other in a major axis direction of the first oblate circle. The first and second semiconductor pillars extend in the stacking direction. The first and second charge storage layers are provided between the electrode film and the first and second semiconductor pillars, respectively.
    Type: Application
    Filed: April 5, 2013
    Publication date: September 5, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Hiroyasu TANAKA, Hideaki Aochi, Ryota Katsumata, Masaru Kidoh, Masaru Kito, Yoshiaki Fukuzumi, Yosuke Komori, Megumi Ishiduki, Tomoko Fujiwara, Junya Matsunami, Ryouhei Kirisawa
  • Patent number: 8440528
    Abstract: A nonvolatile semiconductor memory device includes: forming a stacked body by alternately stacking a plurality of interlayer insulating films and a plurality of control gate electrodes; forming a through-hole extending in a stacking direction in the stacked body; etching a portion of the interlayer insulating film facing the through-hole via the through-hole to remove the portion; forming a removed portion; forming a first insulating film on inner faces of the through-hole and the portion in which the interlayer insulating films are removed; forming a floating gate electrode in the portion in which the interlayer insulating films are removed; forming a second insulating film so as to cover a portion of the floating gate electrode facing the through-hole; and burying a semiconductor pillar in the through-hole.
    Type: Grant
    Filed: December 15, 2009
    Date of Patent: May 14, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masaru Kito, Masaru Kidoh, Tomoko Fujiwara, Yosuke Komori, Megumi Ishiduki, Hiroyasu Tanaka, Yoshiaki Fukuzumi, Ryota Katsumata, Ryouhei Kirisawa, Junya Matsunami, Hideaki Aochi
  • Patent number: 8436414
    Abstract: A nonvolatile semiconductor memory device includes: a semiconductor substrate; a stacked body provided on the semiconductor substrate, the stacked body having electrode films and insulating films being alternately stacked; a first and second semiconductor pillars; and a first and second charge storage layers. The first and second semiconductor pillars are provided inside a through hole penetrating through the stacked body in a stacking direction of the stacked body. The through hole has a cross section of an oblate circle, when cutting in a direction perpendicular to the stacking direction. The first and second semiconductor pillars face each other in a major axis direction of the first oblate circle. The first and second semiconductor pillars extend in the stacking direction. The first and second charge storage layers are provided between the electrode film and the first and second semiconductor pillars, respectively.
    Type: Grant
    Filed: February 16, 2010
    Date of Patent: May 7, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroyasu Tanaka, Hideaki Aochi, Ryota Katsumata, Masaru Kidoh, Masaru Kito, Yoshiaki Fukuzumi, Yosuke Komori, Megumi Ishiduki, Tomoko Fujiwara, Junya Matsunami, Ryouhei Kirisawa
  • Patent number: 8436415
    Abstract: A memory string comprises: a first semiconductor layer including a columnar portion extending in a stacking direction on a substrate; a first charge storage layer surrounding the columnar portion; and a plurality of first conductive layers stacked on the substrate so as to surround the first charge storage layer. A select transistor comprises: a second semiconductor layer in contact with an upper surface of the columnar portion and extending in the stacking direction; a second charge storage layer surrounding the second semiconductor layer; and a second conductive layer deposited above the first conductive layer to surround the second charge storage layer. The second charge storage layer is formed from a layer downward of the second conductive layer to an upper end vicinity of the second conductive layer, and is not formed in a layer upward of the upper end vicinity.
    Type: Grant
    Filed: March 15, 2010
    Date of Patent: May 7, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masaru Kidoh, Ryota Katsumata, Masaru Kito, Yoshiaki Fukuzumi, Hiroyasu Tanaka, Yosuke Komori, Megumi Ishiduki, Tomoko Fujiwara, Hideaki Aochi, Ryouhei Kirisawa, Yoshimasa Mikajiri, Shigeto Oota
  • Publication number: 20130075918
    Abstract: In one embodiment, a shift register memory includes a substrate, and a channel layer provided on the substrate, and having a helical shape rotating around an axis which is perpendicular to a surface of the substrate. The memory further includes at least three control electrodes provided on the substrate, extending in a direction parallel to the axis, and to be used to transfer charges in the channel layer.
    Type: Application
    Filed: February 27, 2012
    Publication date: March 28, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki FUKUZUMI, Hideaki AOCHI, Tomoko FUJIWARA
  • Patent number: 8400842
    Abstract: According to one embodiment, a nonvolatile semiconductor memory device includes a memory unit and a control unit. The memory unit includes a charge storage film, a first insulating film provided adjacent to one surface of the charge storage film, a second insulating film provided adjacent to one other surface of the charge storage film, a semiconductor portion provided adjacent to the first insulating film and a plurality of electrode portions provided adjacent to the second insulating film. The control unit performs a control of applying a first voltage to electrode portions adjacent to each other in one direction at different timing respectively, in an erasing. The erasing is performed by at least one selected from injecting electron holes into the charge storage film and removing electrons from the charge storage film. The first voltage is applied from one of the electrode portions to the charge storage film to be erased.
    Type: Grant
    Filed: February 1, 2011
    Date of Patent: March 19, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masaru Kito, Tomoko Fujiwara, Yoshimasa Mikajiri