Patents by Inventor Keisuke Nakatsuka

Keisuke Nakatsuka 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: 20200303395
    Abstract: A semiconductor storage device includes a first conductive layer, a second conductive layer, a third conductive layer, a contact plug, a memory trench extending between the second conductive layer and the third conductive layer. The memory trench is formed around the contact plug, and surrounds a first area in which the contact plug is disposed. A second area is separated from the first area and includes a pillar penetrating the first conductive layer. The second conductive layer extends between the first and second areas, and is connected to the first conductive layer. The third conductive layer is on the opposite side of the first area to the second area, and is connected to the first conductive layer.
    Type: Application
    Filed: September 3, 2019
    Publication date: September 24, 2020
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Keisuke NAKATSUKA, Yoshitaka KUBOTA, Tetsuaki UTSUMI, Yoshiro SHIMOJO, Ryota KATSUMATA
  • Publication number: 20200286828
    Abstract: According to one embodiment, a semiconductor memory device includes: a first semiconductor layer including first to third portions which are arranged along a first direction and differ in position from one another in a second direction; a conductive layer including a fourth portion extending in the second direction and a fifth portion extending in the first direction; a first insulating layer between the fourth portion and the first semiconductor layer and between the fifth portion and the first semiconductor layer; a first contact plug coupled to the fourth portion; a second contact plug coupled to the first semiconductor layer in a region where the first insulating layer is formed; a first interconnect; and a first memory cell apart from the fifth portion in the first direction and storing information between the semiconductor layer and the first interconnect.
    Type: Application
    Filed: September 9, 2019
    Publication date: September 10, 2020
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Keiji HOSOTANI, Fumitaka ARAI, Keisuke NAKATSUKA, Nobuyuki MOMO, Motohiko FUJIMATSU
  • Patent number: 10748920
    Abstract: According to one embodiment, a semiconductor memory device includes a plurality of electrode films, a semiconductor member, a tunneling insulating film, a charge storage member, and a blocking insulating film. The plurality of electrode films are arranged to be separated from each other along a first direction. The semiconductor member extends in the first direction. The tunneling insulating film is provided between the semiconductor member and the electrode films. The charge storage member is provided between the tunneling insulating film and the electrode films. The blocking insulating film is provided between the charge storage member and the electrode films. The blocking insulating film includes a first film contacting the charge storage film and including carbon-containing silicon oxide, and a second film contacting the electrode films and including hafnium oxide or aluminum oxide.
    Type: Grant
    Filed: September 10, 2018
    Date of Patent: August 18, 2020
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventor: Keisuke Nakatsuka
  • Publication number: 20200176033
    Abstract: According to one embodiment, a semiconductor memory device includes: a conductive layer including a first portion and a second portion electrically coupled to the first portion; a first contact plug electrically coupled to the first portion; a first semiconductor layer; a first insulating layer between the second portion and the first semiconductor layer, and between the first portion and the first semiconductor layer; a second contact plug coupled to the first semiconductor layer in a region in which the first insulating layer is formed; a first interconnect; and a first memory cell apart from the second portion in the second direction and storing information between the first semiconductor layer and the first interconnect.
    Type: Application
    Filed: September 5, 2019
    Publication date: June 4, 2020
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Keiji HOSOTANI, Fumitaka ARAI, Keisuke NAKATSUKA
  • Patent number: 10636809
    Abstract: A semiconductor memory device includes a plurality of electrode films and a plurality of first insulating films stacked alternately along a first direction, a semiconductor member extending in the first direction, a charge storage member provided between the semiconductor member and the electrode films, and a second insulating film provided between the charge storage member and the electrode films. At least one of the plurality of first insulating films includes one or more types of a first material selected from the group consisting of silicon nitride, hafnium oxide, silicon oxynitride, and aluminum oxide.
    Type: Grant
    Filed: September 10, 2018
    Date of Patent: April 28, 2020
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventor: Keisuke Nakatsuka
  • Publication number: 20200091183
    Abstract: A semiconductor memory device includes first structure bodies and second structure bodies arranged alternately along a first direction. The first structure body includes electrode films arranged along a second direction. The second structure body includes columnar members, first insulating members, and second insulating members. The columnar member includes a semiconductor member extending in the second direction and a charge storage member provided between the semiconductor member and the electrode film. The second insulating members are arranged along a third direction. Lengths in the first direction of the second insulating members are longer than lengths in the first direction of the first insulating members. Positions of the second insulating members in the third direction are different from each other between the second structure bodies adjacent to each other in the first direction. The columnar members and the first insulating members are arranged alternately between the second insulating members.
    Type: Application
    Filed: March 12, 2019
    Publication date: March 19, 2020
    Applicant: Toshiba Memory Corporation
    Inventor: Keisuke NAKATSUKA
  • Publication number: 20200090710
    Abstract: A data latch circuit includes a first n-channel transistor and a first p-channel transistor. A gate of the first n-channel transistor and a gate of the first p-channel transistor are a common gate.
    Type: Application
    Filed: March 18, 2019
    Publication date: March 19, 2020
    Applicant: Toshiba Memory Corporation
    Inventors: Keisuke NAKATSUKA, Tomoya SANUKI, Takashi MAEDA, Go SHIKATA, Hideaki AOCHI
  • Publication number: 20190333928
    Abstract: According to one embodiment, a semiconductor memory device includes: first and second signal lines; a first memory cell storing first information by applying voltage across the first signal line and a first interconnect layer; a second memory cell storing second information by applying voltage across the second signal line and a second interconnect layer; a first conductive layer provided on the first and second signal lines; third and fourth signal lines provided on the first conductive layer; a third memory cell storing third information by applying voltage across the third signal line and a third interconnect layer; and a fourth memory cell storing fourth information by applying voltage across the fourth signal line and a fourth interconnect layer.
    Type: Application
    Filed: March 11, 2019
    Publication date: October 31, 2019
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Satoshi NAGASHIMA, Keisuke NAKATSUKA, Fumitaka ARAI, Shinya ARAI, Yasuhiro UCHIYAMA
  • Publication number: 20190267392
    Abstract: A semiconductor memory device includes a plurality of electrode films and a plurality of first insulating films stacked alternately along a first direction, a semiconductor member extending in the first direction, a charge storage member provided between the semiconductor member and the electrode films, and a second insulating film provided between the charge storage member and the electrode films. At least one of the plurality of first insulating films includes one or more types of a first material selected from the group consisting of silicon nitride, hafnium oxide, silicon oxynitride, and aluminum oxide.
    Type: Application
    Filed: September 10, 2018
    Publication date: August 29, 2019
    Applicant: Toshiba Memory Corporation
    Inventor: Keisuke NAKATSUKA
  • Publication number: 20190259775
    Abstract: According to one embodiment, a semiconductor memory device includes a plurality of electrode films, a semiconductor member, a tunneling insulating film, a charge storage member, and a blocking insulating film. The plurality of electrode films are arranged to be separated from each other along a first direction. The semiconductor member extends in the first direction. The tunneling insulating film is provided between the semiconductor member and the electrode films. The charge storage member is provided between the tunneling insulating film and the electrode films. The blocking insulating film is provided between the charge storage member and the electrode films. The blocking insulating film includes a first film contacting the charge storage film and including carbon-containing silicon oxide, and a second film contacting the electrode films and including hafnium oxide or aluminum oxide.
    Type: Application
    Filed: September 10, 2018
    Publication date: August 22, 2019
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventor: Keisuke NAKATSUKA
  • Patent number: 10311929
    Abstract: According to an embodiment, a resistance change memory includes a semiconductor substrate, a transistor having a control terminal, a first terminal and a second terminal, the transistor provided on the semiconductor substrate, an insulating layer covering the transistor, a first conductive line connected to the first terminal and provided on the insulating layer, a second conductive line provided on the insulating layer, and a resistance change element connected between the second terminal and the second conductive line. The first conductive line has a width greater than a width of the second conductive line in a direction in which the first and second conductive lines are arranged.
    Type: Grant
    Filed: December 8, 2017
    Date of Patent: June 4, 2019
    Assignees: TOSHIBA MEMORY CORPORATION, SK HYNIX INC.
    Inventors: Hisanori Aikawa, Tatsuya Kishi, Keisuke Nakatsuka, Satoshi Inaba, Masaru Toko, Keiji Hosotani, Jae Yun Yi, Hong Ju Suh, Se Dong Kim
  • Patent number: 10049711
    Abstract: According to one embodiment, a magnetoresistive memory device includes a substrate having a first surface which includes a first direction; and memory elements each having a switchable resistance. A first column of memory elements lined up along the first direction is different from an adjacent second column of memory elements lined up along the first direction at positions of memory elements in the first direction.
    Type: Grant
    Filed: September 6, 2016
    Date of Patent: August 14, 2018
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Keisuke Nakatsuka, Tadashi Miyakawa, Katsuhiko Hoya, Takeshi Hamamoto, Hiroyuki Takenaka
  • Patent number: 10020040
    Abstract: According to one embodiment, a semiconductor memory device comprises: first to fourth memory cells, each of which is configured to have a first resistance state or a second resistance state; and a first circuit configured to output first data based on a first signal representing a resistance state of the first memory cell and a second signal representing a resistance state of the second memory cell, output second data based on the second signal and a third signal representing a resistance state of the third memory cell, and output third data based on the third signal and a fourth signal representing a resistance state of the fourth memory cell.
    Type: Grant
    Filed: March 10, 2017
    Date of Patent: July 10, 2018
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Keisuke Nakatsuka, Tsuneo Inaba, Yutaka Shirai
  • Publication number: 20180102156
    Abstract: According to an embodiment, a resistance change memory includes a semiconductor substrate, a transistor having a control terminal, a first terminal and a second terminal, the transistor provided on the semiconductor substrate, an insulating layer covering the transistor, a first conductive line connected to the first terminal and provided on the insulating layer, a second conductive line provided on the insulating layer, and a resistance change element connected between the second terminal and the second conductive line. The first conductive line has a width greater than a width of the second conductive line in a direction in which the first and second conductive lines are arranged.
    Type: Application
    Filed: December 8, 2017
    Publication date: April 12, 2018
    Applicants: TOSHIBA MEMORY CORPORATION, SK HYNIX INC.
    Inventors: Hisanori AIKAWA, Tatsuya KISHI, Keisuke NAKATSUKA, Satoshi INABA, Masaru TOKO, Keiji HOSOTANI, Jae Yun YI, Hong Ju SUH, Se Dong KIM
  • Patent number: 9934834
    Abstract: A magnetoresistive memory device includes a variable resistance element and a read circuit. The resistance element has a resistance state, which is one of switchable first and second resistance states. The first and second resistance states exhibit different resistances. Each of the first and second resistance states is reached by a current flowing through the variable resistance element in one of opposing first and second directions. The read circuit passes a read current through the variable resistance element autonomously in the first or second direction in accordance with the resistance state of the variable resistance element.
    Type: Grant
    Filed: August 26, 2016
    Date of Patent: April 3, 2018
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Keisuke Nakatsuka, Katsuhiko Hoya
  • Publication number: 20180075892
    Abstract: According to one embodiment, a semiconductor memory device comprises: first to fourth memory cells, each of which is configured to have a first resistance state or a second resistance state; and a first circuit configured to output first data based on a first signal representing a resistance state of the first memory cell and a second signal representing a resistance state of the second memory cell, output second data based on the second signal and a third signal representing a resistance state of the third memory cell, and output third data based on the third signal and a fourth signal representing a resistance state of the fourth memory cell.
    Type: Application
    Filed: March 10, 2017
    Publication date: March 15, 2018
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Keisuke NAKATSUKA, Tsuneo INABA, Yutaka SHIRAI
  • Patent number: 9887237
    Abstract: According to an embodiment, a magnetic storage device includes a semiconductor region including a trench; a gate electrode disposed in the trench; an insulation film covering the gate electrode and provided in a manner to fill the trench; and a magnetoresistive effect element including at least a first ferromagnetic layer, a second ferromagnetic layer, and a non-magnetic layer provided between the first ferromagnetic layer and the second ferromagnetic layer, the non-magnetic layer in a side surface of the magnetoresistive effect element including the non-magnetic layer being provided on a top surface of the insulation film.
    Type: Grant
    Filed: March 9, 2016
    Date of Patent: February 6, 2018
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Shintaro Sakai, Keisuke Nakatsuka, Hiroyuki Kanaya, Yoshinori Kumura, Katsuyuki Fujita
  • Patent number: 9773539
    Abstract: According to one embodiment, a logical operation circuit includes a magnetic tunnel junction (MTJ) element and driver. The MTJ element includes a first magnetic layer, a second magnetic layer, and an intermediate layer between the first and second magnetic layers. An orientation of magnetization of the second magnetic layer flips by a first current which flows through the MTJ element in a first state from the second magnetic layer to the first magnetic layer. The driver is coupled to the first magnetic layer without a magnetic layer interposed and coupled to the second magnetic layer, and passes a second current through the MTJ element in the first state from the second magnetic layer to the first magnetic layer. A magnitude of the second current is larger than 1.5 times a magnitude of the first current.
    Type: Grant
    Filed: December 18, 2015
    Date of Patent: September 26, 2017
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventor: Keisuke Nakatsuka
  • Patent number: 9728242
    Abstract: According to one embodiment, a memory device includes a spin transfer torque magnetoresistive element including a first magnetic layer, a second magnetic layer, and a nonmagnetic layer between the first magnetic layer and the second magnetic layer, a temperature detecting unit detecting an ambient temperature of the magnetoresistive element, and a write voltage generating unit generating a write voltage for the magnetoresistive element in accordance with the temperature detected by the temperature detecting unit.
    Type: Grant
    Filed: September 15, 2016
    Date of Patent: August 8, 2017
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventors: Motoyuki Sato, Kazumasa Sunouchi, Keisuke Nakatsuka
  • Publication number: 20170141157
    Abstract: According to an embodiment, a magnetic storage device includes a semiconductor region including a trench; a gate electrode disposed in the trench; an insulation film covering the gate electrode and provided in a manner to fill the trench; and a magnetoresistive effect element including at least a first ferromagnetic layer, a second ferromagnetic layer, and a non-magnetic layer provided between the first ferromagnetic layer and the second ferromagnetic layer, the non-magnetic layer in a side surface of the magnetoresistive effect element including the non-magnetic layer being provided on a top surface of the insulation film.
    Type: Application
    Filed: March 9, 2016
    Publication date: May 18, 2017
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Shintaro SAKAI, Keisuke NAKATSUKA, Hiroyuki KANAYA, Yoshinori KUMURA, Katsuyuki FUJITA