Patents by Inventor Tatsuo Izumi

Tatsuo Izumi 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: 11849586
    Abstract: A semiconductor device is provided, including: a substrate; a first stacked portion including a plurality of first electrode layers stacked in a first direction via a first insulator; a second stacked portion provided above the first stacked portion and including a plurality of second electrode layers stacked in the first direction via a second insulator; a connection portion provided between the first stacked portion and the second stacked portion, and including a third insulator; a column-shaped portion extending in the first stacked portion, the second stacked portion, and the connection portion in the first direction, and including a semiconductor body and a charge storage portion; and a semiconductor pillar provided between the substrate and the column-shaped portion, and in contact with the substrate and the semiconductor body of the column-shaped portion.
    Type: Grant
    Filed: October 3, 2022
    Date of Patent: December 19, 2023
    Assignee: Kioxia Corporation
    Inventors: Kaito Shirai, Hideto Takekida, Tatsuo Izumi, Reiko Shamoto, Takahisa Kanemura, Shigeo Kondo
  • Publication number: 20230395154
    Abstract: A semiconductor memory device includes a first wiring, a first memory transistor connected to the first wiring, a first transistor connected between the first wiring and the first memory transistor, a second transistor connected between the first wiring and the first transistor, and second to fourth wirings respectively connected to gate electrodes of the first memory transistor, the first transistor, and the second transistor. From a first timing to a second timing, a voltage difference between the first wiring and the third wiring is maintained at a predetermined value, a voltage difference between the third wiring and the fourth wiring is maintained at a predetermined value, a voltage of the first wiring becomes larger than a voltage of the third wiring, and the voltage of the third wiring becomes larger than a voltage of the fourth wiring.
    Type: Application
    Filed: August 17, 2023
    Publication date: December 7, 2023
    Applicant: KIOXIA CORPORATION
    Inventors: Yuki SAKAGUCHI, Tatsuo IZUMI, Masashi YOSHIDA
  • Patent number: 11769553
    Abstract: A semiconductor memory device includes a first wiring, a first memory transistor connected to the first wiring, a first transistor connected between the first wiring and the first memory transistor, a second transistor connected between the first wiring and the first transistor, and second to fourth wirings respectively connected to gate electrodes of the first memory transistor, the first transistor, and the second transistor. From a first timing to a second timing, a voltage difference between the first wiring and the third wiring is maintained at a predetermined value, a voltage difference between the third wiring and the fourth wiring is maintained at a predetermined value, a voltage of the first wiring becomes larger than a voltage of the third wiring, and the voltage of the third wiring becomes larger than a voltage of the fourth wiring.
    Type: Grant
    Filed: April 6, 2021
    Date of Patent: September 26, 2023
    Assignee: Kioxia Corporation
    Inventors: Yuki Sakaguchi, Tatsuo Izumi, Masashi Yoshida
  • Patent number: 11569253
    Abstract: A semiconductor memory device includes multiple first electrode layers stacked in a first direction, multiple second electrode layers stacked in the first direction, a first columnar body extending through the multiple first electrode layers in the first direction, a second columnar body extending through the multiple second electrode layers in the first direction, a connection part connecting the first columnar body and the second columnar body, and a spacer film having an island configuration surrounding the connection part. The multiple first electrode layers and the multiple second electrode layers are arranged in the first direction, and the connection part and the spacer film are provided between the multiple first electrode layers and the multiple second electrode layers.
    Type: Grant
    Filed: September 1, 2020
    Date of Patent: January 31, 2023
    Assignee: Kioxia Corporation
    Inventors: Takeshi Nagatomo, Tatsuo Izumi, Ryota Suzuki, Takuya Nishikawa, Yasuhito Nakajima, Daiki Takayama, Hiroaki Naito, Genki Kawaguchi
  • Publication number: 20230027173
    Abstract: A semiconductor device is provided, including: a substrate; a first stacked portion including a plurality of first electrode layers stacked in a first direction via a first insulator; a second stacked portion provided above the first stacked portion and including a plurality of second electrode layers stacked in the first direction via a second insulator; a connection portion provided between the first stacked portion and the second stacked portion, and including a third insulator; a column-shaped portion extending in the first stacked portion, the second stacked portion, and the connection portion in the first direction, and including a semiconductor body and a charge storage portion; and a semiconductor pillar provided between the substrate and the column-shaped portion, and in contact with the substrate and the semiconductor body of the column-shaped portion.
    Type: Application
    Filed: October 3, 2022
    Publication date: January 26, 2023
    Applicant: Kioxia Corporation
    Inventors: Kaito SHIRAI, Hideto TAKEKIDA, Tatsuo IZUMI, Reiko SHAMOTO, Takahisa KANEMURA, Shigeo KONDO
  • Patent number: 11502100
    Abstract: According to one embodiment, the stacked body includes a first stacked portion including a plurality of electrode layers, a second stacked portion including a plurality of electrode layers, and being disposed separately from the first stacked portion in the first direction, and a connection portion including a high dielectric layer provided between the first stacked portion and the second stacked portion and having a dielectric constant higher than a dielectric constant of the insulator. The column-shaped portion includes a first portion provided in the first stacked portion and extending in the first direction of the stacked body, a second portion provided in the second stacked portion and extending in the first direction, and an intermediate portion provided in the connection portion and connected the first portion to the second portion.
    Type: Grant
    Filed: September 3, 2020
    Date of Patent: November 15, 2022
    Assignee: Kioxia Corporation
    Inventors: Kaito Shirai, Hideto Takekida, Tatsuo Izumi, Reiko Shamoto, Takahisa Kanemura, Shigeo Kondo
  • Patent number: 11264061
    Abstract: According to one embodiment, a method of controlling a memory device includes supplying a second potential having a first value to a second electrode and simultaneously, or thereafter, supplying a third potential to a third electrode, and thereafter stopping supply of the third potential such that the potential of the third electrode decays while reducing the potential of the second electrode, and thereafter supplying a first potential to the first electrode.
    Type: Grant
    Filed: March 10, 2021
    Date of Patent: March 1, 2022
    Assignee: KIOXIA CORPORATION
    Inventors: Ryota Suzuki, Tatsuo Izumi
  • Publication number: 20210249440
    Abstract: A memory device includes a conductive layer, a plurality of first electrode layers, a first semiconductor layer extending through the plurality of first electrode layers in a first direction toward the plurality of first electrode layers from the conductive layer, a first insulating film including a tunneling insulator film, a charge-trapping film and a blocking insulator film, a second electrode layer, and a semiconductor base. The charge-trapping film is spaced along the first direction from the semiconductor base, a distance in the first direction between the charge-trapping film and the semiconductor base is larger than a thickness of the blocking insulator film in a second direction toward the plurality of first electrode layers from the first semiconductor layer.
    Type: Application
    Filed: April 28, 2021
    Publication date: August 12, 2021
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Reiko KOMIYA, Tatsuo IZUMI, Takaya YAMANAKA, Takeshi NAGATOMO, Karin TAKAGI
  • Publication number: 20210225449
    Abstract: A semiconductor memory device includes a first wiring, a first memory transistor connected to the first wiring, a first transistor connected between the first wiring and the first memory transistor, a second transistor connected between the first wiring and the first transistor, and second to fourth wirings respectively connected to gate electrodes of the first memory transistor, the first transistor, and the second transistor. From a first timing to a second timing, a voltage difference between the first wiring and the third wiring is maintained at a predetermined value, a voltage difference between the third wiring and the fourth wiring is maintained at a predetermined value, a voltage of the first wiring becomes larger than a voltage of the third wiring, and the voltage of the third wiring becomes larger than a voltage of the fourth wiring.
    Type: Application
    Filed: April 6, 2021
    Publication date: July 22, 2021
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Yuki SAKAGUCHI, Tatsuo IZUMI, Masashi YOSHIDA
  • Publication number: 20210193194
    Abstract: According to one embodiment, a method of controlling a memory device includes supplying a second potential having a first value to a second electrode and simultaneously, or thereafter, supplying a third potential to a third electrode, and thereafter stopping supply of the third potential such that the potential of the third electrode decays while reducing the potential of the second electrode, and thereafter supplying a first potential to the first electrode.
    Type: Application
    Filed: March 10, 2021
    Publication date: June 24, 2021
    Inventors: Ryota SUZUKI, Tatsuo Izumi
  • Patent number: 11024646
    Abstract: A memory device includes a conductive layer, a plurality of first electrode layers, a first semiconductor layer extending through the plurality of first electrode layers in a first direction toward the plurality of first electrode layers from the conductive layer, a first insulating film including a tunneling insulator film, a charge-trapping film and a blocking insulator film, a second electrode layer, and a semiconductor base. The charge-trapping film is spaced along the first direction from the semiconductor base, a distance in the first direction between the charge-trapping film and the semiconductor base is larger than a thickness of the blocking insulator film in a second direction toward the plurality of first electrode layers from the first semiconductor layer.
    Type: Grant
    Filed: November 26, 2019
    Date of Patent: June 1, 2021
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Reiko Komiya, Tatsuo Izumi, Takaya Yamanaka, Takeshi Nagatomo, Karin Takagi
  • Patent number: 10991431
    Abstract: A semiconductor memory device includes a first wiring, a first memory transistor connected to the first wiring, a first transistor connected between the first wiring and the first memory transistor, a second transistor connected between the first wiring and the first transistor, and second to fourth wirings respectively connected to gate electrodes of the first memory transistor, the first transistor, and the second transistor. From a first timing to a second timing, a voltage difference between the first wiring and the third wiring is maintained at a predetermined value, a voltage difference between the third wiring and the fourth wiring is maintained at a predetermined value, a voltage of the first wiring becomes larger than a voltage of the third wiring, and the voltage of the third wiring becomes larger than a voltage of the fourth wiring.
    Type: Grant
    Filed: September 12, 2019
    Date of Patent: April 27, 2021
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Yuki Sakaguchi, Tatsuo Izumi, Masashi Yoshida
  • Publication number: 20200403000
    Abstract: According to one embodiment, the stacked body includes a first stacked portion including a plurality of electrode layers, a second stacked portion including a plurality of electrode layers, and being disposed separately from the first stacked portion in the first direction, and a connection portion including a high dielectric layer provided between the first stacked portion and the second stacked portion and having a dielectric constant higher than a dielectric constant of the insulator. The column-shaped portion includes a first portion provided in the first stacked portion and extending in the first direction of the stacked body, a second portion provided in the second stacked portion and extending in the first direction, and an intermediate portion provided in the connection portion and connected the first portion to the second portion.
    Type: Application
    Filed: September 3, 2020
    Publication date: December 24, 2020
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Kaito SHIRAI, Hideto Takekida, Tatsuo Izumi, Reiko Shamoto, Takahisa Kanemura, Shigeo Kondo
  • Publication number: 20200395371
    Abstract: A semiconductor memory device includes multiple first electrode layers stacked in a first direction, multiple second electrode layers stacked in the first direction, a first columnar body extending through the multiple first electrode layers in the first direction, a second columnar body extending through the multiple second electrode layers in the first direction, a connection part connecting the first columnar body and the second columnar body, and a spacer film having an island configuration surrounding the connection part. The multiple first electrode layers and the multiple second electrode layers are arranged in the first direction, and the connection part and the spacer film are provided between the multiple first electrode layers and the multiple second electrode layers.
    Type: Application
    Filed: September 1, 2020
    Publication date: December 17, 2020
    Inventors: Takeshi NAGATOMO, Tatsuo Izumi, Ryota Suzuki, Takuya Nishikawa, Yasuhito Nakajima, Daiki Takayama, Hiroaki Naito, Genki Kawaguchi
  • Patent number: 10804290
    Abstract: According to one embodiment, the stacked body includes a first stacked portion including a plurality of electrode layers, a second stacked portion including a plurality of electrode layers, and being disposed separately from the first stacked portion in the first direction, and a connection portion including a high dielectric layer provided between the first stacked portion and the second stacked portion and having a dielectric constant higher than a dielectric constant of the insulator. The column-shaped portion includes a first portion provided in the first stacked portion and extending in the first direction of the stacked body, a second portion provided in the second stacked portion and extending in the first direction, and an intermediate portion provided in the connection portion and connected the first portion to the second portion.
    Type: Grant
    Filed: March 13, 2019
    Date of Patent: October 13, 2020
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Kaito Shirai, Hideto Takekida, Tatsuo Izumi, Reiko Shamoto, Takahisa Kanemura, Shigeo Kondo
  • Publication number: 20200286564
    Abstract: A semiconductor memory device includes a first wiring, a first memory transistor connected to the first wiring, a first transistor connected between the first wiring and the first memory transistor, a second transistor connected between the first wiring and the first transistor, and second to fourth wirings respectively connected to gate electrodes of the first memory transistor, the first transistor, and the second transistor. From a first timing to a second timing, a voltage difference between the first wiring and the third wiring is maintained at a predetermined value, a voltage difference between the third wiring and the fourth wiring is maintained at a predetermined value, a voltage of the first wiring becomes larger than a voltage of the third wiring, and the voltage of the third wiring becomes larger than a voltage of the fourth wiring.
    Type: Application
    Filed: September 12, 2019
    Publication date: September 10, 2020
    Applicant: Toshiba Memory Corporation
    Inventors: Yuki SAKAGUCHI, Tatsuo Izumi, Masashi Yoshida
  • Publication number: 20200098790
    Abstract: A memory device includes first electrode layers stacked in a first direction, a first semiconductor layer piercing the first electrode layers in a first direction, a first insulating film surrounding the first semiconductor layer, and a semiconductor base connected to the first semiconductor layer. The first insulating film includes a first film, a second film, and a third film provided in order in a second direction from the first semiconductor layer toward one of first electrode layers. Spacing in the first direction between the second film and the semiconductor base is wider than a film thickness of the third film in the second direction. A minimum width of an outer perimeter of the first semiconductor layer is substantially the same as a width of an outer perimeter at a portion of the first semiconductor layer piercing the most proximal first electrode layer.
    Type: Application
    Filed: November 26, 2019
    Publication date: March 26, 2020
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Reiko KOMIYA, Tatsuo IZUMI, Takaya YAMANAKA, Takeshi NAGATOMO, Karin TAKAGI
  • Patent number: 10593696
    Abstract: A semiconductor memory device includes a conductive layer; a first electrode layer provided above the conductive layer; a second electrode layer provided between the conductive layer and the first electrode layer; a first semiconductor channel body extending through the first electrode layer in a first direction from the conductive layer to the first electrode layer; a second semiconductor channel body provided between the conductive layer and the first semiconductor channel body, the second semiconductor channel body extending through the second electrode layer; and an insulating layer provided between the second semiconductor channel body and the second electrode layer. The second semiconductor channel body includes a first recessed portion in a lateral surface facing the second electrode layer, and the second electrode layer includes a second recessed portion in a surface facing the second semiconductor channel body.
    Type: Grant
    Filed: May 10, 2019
    Date of Patent: March 17, 2020
    Assignee: Toshiba Memory Corporation
    Inventors: Kazuharu Yamabe, Ryota Suzuki, Tatsuo Izumi, Masahiro Fukuda, Takuo Ohashi
  • Patent number: 10529735
    Abstract: A memory device includes first electrode layers stacked in a first direction, a first semiconductor layer piercing the first electrode layers in a first direction, a first insulating film surrounding the first semiconductor layer, and a semiconductor base connected to the first semiconductor layer. The first insulating film includes a first film, a second film, and a third film provided in order in a second direction from the first semiconductor layer toward one of first electrode layers. Spacing in the first direction between the second film and the semiconductor base is wider than a film thickness of the third film in the second direction. A minimum width of an outer perimeter of the first semiconductor layer is substantially the same as a width of an outer perimeter at a portion of the first semiconductor layer piercing the most proximal first electrode layer.
    Type: Grant
    Filed: September 11, 2018
    Date of Patent: January 7, 2020
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Reiko Komiya, Tatsuo Izumi, Takaya Yamanaka, Takeshi Nagatomo, Karin Takagi
  • Patent number: 10510417
    Abstract: According to one embodiment, a semiconductor memory device includes: a first memory unit including first and second memory cells; a second memory unit including third and fourth memory cells; a third memory unit including fifth and sixth memory cells; a first word line coupled to gates of the first, third, and fifth memory cells; and a second word line coupled to gates of the second, fourth, and sixth memory cells. In a write operation, the first memory cell, the third memory cell, the fifth memory cell, the sixth memory cell, the fourth memory cell, and the second memory cell are written in this order.
    Type: Grant
    Filed: August 13, 2018
    Date of Patent: December 17, 2019
    Assignee: Toshiba Memory Corporation
    Inventors: Kazuharu Yamabe, Tatsuo Izumi