Patents by Inventor Kensuke Ota

Kensuke Ota 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: 20240087633
    Abstract: According to one embodiment, a memory device includes a pillar extending in a first direction through a first, second, and third conductive layers. The pillar includes ferroelectric layer. A first transistor is at an intersection of the pillar and the first conductive layer. A second transistor is at an intersection of the pillar and the second conductive layer. A ferroelectric memory cell is at an intersection with the third conductive layer and the pillar. A circuit supplies a read pulse to the memory cell in a read sequence. The read pulse has a first voltage value in a first period and has a second voltage value with the same polarity as the first voltage value in a second period after the first period. The second voltage value is lower than the first.
    Type: Application
    Filed: August 25, 2023
    Publication date: March 14, 2024
    Inventors: Reika TANAKA, Kensuke OTA, Masamichi SUZUKI
  • Publication number: 20230320093
    Abstract: A semiconductor memory device according to an embodiment includes a stacked body in which a gate electrode layer and a first insulating layer are alternately stacked in a first direction, a semiconductor layer in the stacked body and extending in the first direction, a second insulating layer between the semiconductor layer and the stacked body, a third insulating layer provided between the second insulating layer and the stacked body, and a first layer between the second insulating layer and the third insulating layer. The first layer contains silicon and nitrogen and includes a first region between the gate electrode layer and the semiconductor layer and a second region between the first insulating layer and the semiconductor layer, the first region contains or does not contain fluorine, the second region contains fluorine, and a fluorine concentration of the second region is higher than a fluorine concentration of the first region.
    Type: Application
    Filed: September 2, 2022
    Publication date: October 5, 2023
    Applicant: Kioxia Corporation
    Inventors: Harumi SEKI, Masamichi SUZUKI, Reika TANAKA, Kensuke OTA, Yusuke HIGASHI
  • Publication number: 20230298643
    Abstract: A semiconductor device according to an embodiment includes first to fifth interconnects, first to third memory cells, and a control circuit. The control circuit is configured to execute machine learning. Each of the first memory cells, the second memory cells, and the third memory cells includes a resistance changing element. In the machine learning, the control circuit is configured to: execute a write operation using a common write voltage to each of the second memory cells; and after the write operation, input input data to each of the first interconnects, and change a resistance value of at least one third memory cell of the third memory cells based on the input data and a signal output from each of the fifth interconnects based on the input data.
    Type: Application
    Filed: September 14, 2022
    Publication date: September 21, 2023
    Applicant: Kioxia Corporation
    Inventors: Kensuke OTA, Marina YAMAGUCHI, Masatoshi YOSHIKAWA
  • Patent number: 11737281
    Abstract: A semiconductor memory device according to an embodiment includes: a semiconductor layer extending in a first direction; a first gate electrode layer; a first insulating layer between the semiconductor layer and the first gate electrode layer; a second insulating layer between the first insulating layer and the first gate electrode layer, the second insulating layer having a first portion containing a ferroelectric material; and a first layer between the first insulating layer and the second insulating layer, the first layer containing silicon, nitrogen, and fluorine, the first layer having a first region and a second region between the first region and the second insulating layer, the first layer having a second atomic ratio of nitrogen to silicon in the second region higher than a first atomic ratio of nitrogen to silicon in the first region, and the first layer having fluorine concentration higher than the second region.
    Type: Grant
    Filed: December 20, 2021
    Date of Patent: August 22, 2023
    Assignee: Kioxia Corporation
    Inventors: Harumi Seki, Kensuke Ota, Masumi Saitoh
  • Patent number: 11605647
    Abstract: According to one embodiment, a semiconductor memory device includes a ferroelectric layer and a first semiconductor layer. The first semiconductor layer is electrically connected to a first electrode and a second electrode and includes an n-type oxide semiconductor. A third electrode is opposite the first semiconductor layer. The ferroelectric layer is between the third electrode and the first semiconductor layer. A second semiconductor layer includes at least one of a Group IV semiconductor material or a p-type oxide semiconductor material. The first semiconductor layer is between the ferroelectric layer and the second semiconductor layer.
    Type: Grant
    Filed: March 1, 2021
    Date of Patent: March 14, 2023
    Assignee: Kioxia Corporation
    Inventors: Yusuke Tanaka, Masumi Saitoh, Kensuke Ota
  • Patent number: 11574958
    Abstract: A memory device according to an embodiment includes a fluid layer extending in a first direction, a particle in the fluid layer, a first control electrode made of a first material, a first insulating film provided between the fluid layer and the first control electrode, a second control electrode made of a second material and provided to be spaced apart from the first control electrode in the first direction, a second insulating film provided between the fluid layer and the second control electrode, a third control electrode made of a third material different from the first material and the second material and provided between the first control electrode and the second control electrode, and a third insulating film provided between the fluid layer and the third control electrode.
    Type: Grant
    Filed: September 9, 2021
    Date of Patent: February 7, 2023
    Assignee: Kioxia Corporation
    Inventors: Daisuke Matsubayashi, Kensuke Ota
  • Publication number: 20220406796
    Abstract: A semiconductor memory device according to an embodiment includes: a semiconductor layer extending in a first direction; a first gate electrode layer; a first insulating layer between the semiconductor layer and the first gate electrode layer; a second insulating layer between the first insulating layer and the first gate electrode layer, the second insulating layer having a first portion containing a ferroelectric material; and a first layer between the first insulating layer and the second insulating layer, the first layer containing silicon, nitrogen, and fluorine, the first layer having a first region and a second region between the first region and the second insulating layer, the first layer having a second atomic ratio of nitrogen to silicon in the second region higher than a first atomic ratio of nitrogen to silicon in the first region, and the first layer having fluorine concentration higher than the second region.
    Type: Application
    Filed: December 20, 2021
    Publication date: December 22, 2022
    Applicant: Kioxia Corporation
    Inventors: Harumi SEKI, Kensuke OTA, Masumi SAITOH
  • Patent number: 11514970
    Abstract: A memory device according to an embodiment includes first and second interconnects, memory cells, and a control circuit. In a first process, the control circuit applies a write voltage of a first direction to a memory cell coupled to selected first and second interconnects, and applies a write voltage of a second direction to a memory cell coupled to the selected first interconnect and a non-selected second interconnect. In second processes of first to m-th trial processes, the control circuit applies the write voltage of the second direction to the memory cell coupled to the selected first and second interconnects, and omits a write operation in which the memory cell coupled to the selected first interconnect and the non-selected second interconnect is targeted.
    Type: Grant
    Filed: September 9, 2021
    Date of Patent: November 29, 2022
    Assignee: Kioxia Corporation
    Inventors: Marina Yamaguchi, Kensuke Ota, Kazuhiko Yamamoto, Masumi Saitoh
  • Publication number: 20220271093
    Abstract: A memory device according to an embodiment includes a fluid layer extending in a first direction, a particle in the fluid layer, a first control electrode made of a first material, a first insulating film provided between the fluid layer and the first control electrode, a second control electrode made of a second material and provided to be spaced apart from the first control electrode in the first direction, a second insulating film provided between the fluid layer and the second control electrode, a third control electrode made of a third material different from the first material and the second material and provided between the first control electrode and the second control electrode, and a third insulating film provided between the fluid layer and the third control electrode.
    Type: Application
    Filed: September 9, 2021
    Publication date: August 25, 2022
    Applicant: Kioxia Corporation
    Inventors: Daisuke MATSUBAYASHI, Kensuke OTA
  • Publication number: 20220262422
    Abstract: A memory device according to an embodiment includes first and second interconnects, memory cells, and a control circuit. In a first process, the control circuit applies a write voltage of a first direction to a memory cell coupled to selected first and second interconnects, and applies a write voltage of a second direction to a memory cell coupled to the selected first interconnect and a non-selected second interconnect. In second processes of first to m-th trial processes, the control circuit applies the write voltage of the second direction to the memory cell coupled to the selected first and second interconnects, and omits a write operation in which the memory cell coupled to the selected first interconnect and the non-selected second interconnect is targeted.
    Type: Application
    Filed: September 9, 2021
    Publication date: August 18, 2022
    Applicant: Kioxia Corporation
    Inventors: Marina YAMAGUCHI, Kensuke OTA, Kazuhiko YAMAMOTO, Masumi SAITOH
  • Publication number: 20220059570
    Abstract: According to one embodiment, a semiconductor memory device includes a ferroelectric layer and a first semiconductor layer. The first semiconductor layer is electrically connected to a first electrode and a second electrode and includes an n-type oxide semiconductor. A third electrode is opposite the first semiconductor layer. The ferroelectric layer is between the third electrode and the first semiconductor layer. A second semiconductor layer includes at least one of a Group IV semiconductor material or a p-type oxide semiconductor material. The first semiconductor layer is between the ferroelectric layer and the second semiconductor layer.
    Type: Application
    Filed: March 1, 2021
    Publication date: February 24, 2022
    Inventors: Yusuke TANAKA, Masumi SAITOH, Kensuke OTA
  • Patent number: 11195844
    Abstract: A semiconductor memory device includes a substrate, a plurality of conductive layers, a first semiconductor layer, a memory portion, and a drive circuit which drives the memory cell. The conductive layers are provided in a first region, a second region, and a third region different from the first region and the second region, and a portion positioned in the third region is insulated from a portion positioned in the first region and the second region. The drive circuit is provided in the third region, and includes a second semiconductor layer, and an insulating layer, and one end of the second semiconductor layer is connected to the conductive layers in the second region and the other end of the second semiconductor layer is connected to the substrate.
    Type: Grant
    Filed: February 28, 2020
    Date of Patent: December 7, 2021
    Assignee: Kioxia Corporation
    Inventors: Kensuke Ota, Masumi Saitoh, Kiwamu Sakuma
  • Publication number: 20210066316
    Abstract: A semiconductor memory device includes a substrate, a plurality of conductive layers, a first semiconductor layer, a memory portion, and a drive circuit which drives the memory cell. The conductive layers are provided in a first region, a second region, and a third region different from the first region and the second region, and a portion positioned in the third region is insulated from a portion positioned in the first region and the second region. The drive circuit is provided in the third region, and includes a second semiconductor layer, and an insulating layer, and one end of the second semiconductor layer is connected to the conductive layers in the second region and the other end of the second semiconductor layer is connected to the substrate.
    Type: Application
    Filed: February 28, 2020
    Publication date: March 4, 2021
    Applicant: Kioxia Corporation
    Inventors: Kensuke OTA, Masumi SAITOH, Kiwamu SAKUMA
  • Patent number: 10832742
    Abstract: A semiconductor storage device includes a first wire extending in a first direction from a first end to a second end, a plurality of second wires spaced from each other in the first direction and extending in a second direction intersecting the first direction, and a plurality of memory films spaced from each other along the first wire from the first end to the second end and respectively being between the first wire and a second wire of the plurality of second wires. A first memory film of the plurality is at position along the first wire that is between a position of a second memory film and the first end. A contact area between the second memory film and the first wire is greater than a contact area between the first memory film and the first wire.
    Type: Grant
    Filed: August 23, 2019
    Date of Patent: November 10, 2020
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Kensuke Ota, Masumi Saitoh, Kiwamu Sakuma
  • Publication number: 20200265872
    Abstract: A semiconductor storage device includes a first wire extending in a first direction from a first end to a second end, a plurality of second wires spaced from each other in the first direction and extending in a second direction intersecting the first direction, and a plurality of memory films spaced from each other along the first wire from the first end to the second end and respectively being between the first wire and a second wire of the plurality of second wires. A first memory film of the plurality is at position along the first wire that is between a position of a second memory film and the first end. A contact area between the second memory film and the first wire is greater than a contact area between the first memory film and the first wire.
    Type: Application
    Filed: August 23, 2019
    Publication date: August 20, 2020
    Inventors: Kensuke Ota, Masumi Saitoh, Kiwamu Sakuma
  • Patent number: 10658579
    Abstract: A storage device includes a first conductive layer and a second conductive layer, with an intermediate layer therebetween. The intermediate layer includes a first and second compound regions. The first compound region includes first and second adjacent portions and the second compound region includes third and fourth adjacent portions. Electrical resistance between the first and second conductive layers changes according to a polarity applied across the intermediate layer. In a first polarity state, a concentration of a first element in the first portion is higher than a concentration of the first element in the second portion of the first compound region. A thickness of the third portion in the first polarity state is greater than the thickness of the fourth portion in the first polarity state.
    Type: Grant
    Filed: March 1, 2019
    Date of Patent: May 19, 2020
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Kensuke Ota, Yoko Yoshimura, Yoshihiko Moriyama
  • Publication number: 20200020854
    Abstract: A storage device includes a first conductive layer and a second conductive layer, with an intermediate layer therebetween. The intermediate layer includes a first and second compound regions. The first compound region includes first and second adjacent portions and the second compound region includes third and fourth adjacent portions. Electrical resistance between the first and second conductive layers changes according to a polarity applied across the intermediate layer. In a first polarity state, a concentration of a first element in the first portion is higher than a concentration of the first element in the second portion of the first compound region. A thickness of the third portion in the first polarity state is greater than the thickness of the fourth portion in the first polarity state.
    Type: Application
    Filed: March 1, 2019
    Publication date: January 16, 2020
    Inventors: Kensuke OTA, Yoko Yoshimura, Yoshihiko Moriyama
  • Patent number: 10446227
    Abstract: According to one embodiment, a memory device includes: a memory cell including a variable resistance element and connected between a word line and a bit line; and a control circuit configured to control an operation of the memory cell. The variable resistance element includes: a first layer including a first compound including oxygen; a second layer including a second compound including oxygen; and a third layer between the first layer and the second layer.
    Type: Grant
    Filed: March 5, 2018
    Date of Patent: October 15, 2019
    Assignee: Toshiba Memory Corporation
    Inventors: Kensuke Ota, Masamichi Suzuki, Reika Ichihara
  • Patent number: 10347650
    Abstract: A semiconductor memory device includes: a substrate; a memory cell array including memory cells arranged in a first direction intersecting a surface of the substrate; an insulating layer covering the memory cell array; and a transistor provided on the insulating layer. The transistor includes: first and second semiconductor layers provided on the insulating layer; a gate electrode provided between the first and second semiconductor layers, one end in the first direction of the gate electrode being closer to the substrate than the first and second semiconductor layers; a gate insulating film provided on the one end and on side surfaces of the gate electrode; and a third semiconductor layer facing the one end and the side surfaces of the gate electrode. The third semiconductor layer includes a crystal grain larger than a shortest distance between the insulating layer and the gate insulating film.
    Type: Grant
    Filed: August 8, 2018
    Date of Patent: July 9, 2019
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Kiwamu Sakuma, Kensuke Ota, Masumi Saitoh
  • Patent number: 10312289
    Abstract: A semiconductor memory device comprises a substrate, a plurality of first wirings arranged in a first direction crossing a surface of the substrate, a second wiring extending in the first direction, a variable resistance film provided between the first wiring and the second wiring, a third wiring extending in a second direction crossing the first direction, a select transistor provided between an end of the second wiring and the third wiring. In addition, the semiconductor memory device comprises a chalcogen layer provided at at least a position between the end of the second wiring and the select transistor, and, a position between the third wiring and the select transistor.
    Type: Grant
    Filed: July 20, 2018
    Date of Patent: June 4, 2019
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Kensuke Ota, Masumi Saitoh