Patents by Inventor Kiichi Tachi

Kiichi Tachi 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: 20240090239
    Abstract: A semiconductor device includes a metal layer disposed above a transistor on a first substrate. The metal layer includes a first region extending in a first direction and a second region that has a width in the first direction smaller than the first region and protrudes from the first region in a second direction, and has a first corner portion having an angle larger than 180° as viewed in a third direction between a proximal end portion of the second region and the first region. The metal layer includes a first portion that is disposed within the first region and has a lower surface at a first height, and a second portion that is disposed within the second region and has a lower surface at a second height lower than the first height.
    Type: Application
    Filed: March 1, 2023
    Publication date: March 14, 2024
    Applicant: Kioxia Corporation
    Inventors: Kiichi TACHI, Ryota NIHEI, Yoshikazu HOSOMURA
  • Patent number: 11915759
    Abstract: According to one embodiment, a memory system includes a semiconductor memory and a controller. The semiconductor memory includes: first memory cells, first word lines, a first row decoder, and a driver circuit. The first row decoder includes first transistors capable of coupling the first word lines to first signal lines, and a first block decoder supplying a first block selection signal to the first transistors. When the controller issues a data read command, the first block decoder asserts the first block selection signal to allow the first transistors to transfer a first voltage to a selected first word line, and a second voltage to unselected other first word lines. After data is read, the first block decoder continues asserting the first block selection signal, and the driver circuit transfers a third voltage.
    Type: Grant
    Filed: December 20, 2021
    Date of Patent: February 27, 2024
    Assignee: KIOXIA CORPORATION
    Inventors: Masanobu Shirakawa, Marie Takada, Tsukasa Tokutomi, Yoshihisa Kojima, Kiichi Tachi
  • Publication number: 20220262720
    Abstract: A semiconductor storage device includes a first stacked region, a second stacked region, and a connection region arranged between the first and second stacked regions. In the connection region, one of a plurality of conductor layers in an upper stepped portion is connected to one of the plurality of conductor layers in the first stacked region via one of the plurality of conductor layers in a bridge portion.
    Type: Application
    Filed: August 16, 2021
    Publication date: August 18, 2022
    Inventor: Kiichi TACHI
  • Publication number: 20220115070
    Abstract: According to one embodiment, a memory system includes a semiconductor memory and a controller. The semiconductor memory includes: first memory cells, first word lines, a first row decoder, and a driver circuit. The first row decoder includes first transistors capable of coupling the first word lines to first signal lines, and a first block decoder supplying a first block selection signal to the first transistors. When the controller issues a data read command, the first block decoder asserts the first block selection signal to allow the first transistors to transfer a first voltage to a selected first word line, and a second voltage to unselected other first word lines. After data is read, the first block decoder continues asserting the first block selection signal, and the driver circuit transfers a third voltage.
    Type: Application
    Filed: December 20, 2021
    Publication date: April 14, 2022
    Applicant: KIOXIA CORPORATION
    Inventors: Masanobu Shirakawa, Marie Takada, Tsukasa Tokutomi, Yoshihisa Kojima, Kiichi Tachi
  • Patent number: 11264102
    Abstract: A semiconductor storage device includes a bit line driver, and a control circuit configured to be able to execute a writing sequence for repeating at least one loop including a program operation for writing data into at least one of the plurality of memory cells and a verify operation for verifying the data a plurality of times while increasing a program voltage by a step-up voltage. The bit line driver can obtain a number of memory cells into which writing is completed or a number of memory cells into which writing is insufficient for each of the at least two consecutive loops from a result of the verify operation, and the control circuit can determine the step-up voltage in the subsequent loop based on a result obtained by the bit line driver.
    Type: Grant
    Filed: August 31, 2020
    Date of Patent: March 1, 2022
    Assignee: Kioxia Corporation
    Inventors: Kiichi Tachi, Takashi Hirotani
  • Patent number: 11238936
    Abstract: According to one embodiment, a memory system includes a semiconductor memory and a controller. The semiconductor memory includes: first memory cells, first word lines, a first row decoder, and a driver circuit. The first row decoder includes first transistors capable of coupling the first word lines to first signal lines, and a first block decoder supplying a first block selection signal to the first transistors. When the controller issues a data read command, the first block decoder asserts the first block selection signal to allow the first transistors to transfer a first voltage to a selected first word line, and a second voltage to unselected other first word lines. After data is read, the first block decoder continues asserting the first block selection signal, and the driver circuit transfers a third voltage.
    Type: Grant
    Filed: September 8, 2020
    Date of Patent: February 1, 2022
    Assignee: KIOXIA CORPORATION
    Inventors: Masanobu Shirakawa, Marie Takada, Tsukasa Tokutomi, Yoshihisa Kojima, Kiichi Tachi
  • Publication number: 20210125673
    Abstract: A semiconductor storage device includes a bit line driver, and a control circuit configured to be able to execute a writing sequence for repeating at least one loop including a program operation for writing data into at least one of the plurality of memory cells and a verify operation for verifying the data a plurality of times while increasing a program voltage by a step-up voltage. The bit line driver can obtain a number of memory cells into which writing is completed or a number of memory cells into which writing is insufficient for each of the at least two consecutive loops from a result of the verify operation, and the control circuit can determine the step-up voltage in the subsequent loop based on a result obtained by the bit line driver.
    Type: Application
    Filed: August 31, 2020
    Publication date: April 29, 2021
    Applicant: Kioxia Corporation
    Inventors: Kiichi TACHI, Takashi HIROTANI
  • Publication number: 20200402581
    Abstract: According to one embodiment, a memory system includes a semiconductor memory and a controller. The semiconductor memory includes: first memory cells, first word lines, a first row decoder, and a driver circuit. The first row decoder includes first transistors capable of coupling the first word lines to first signal lines, and a first block decoder supplying a first block selection signal to the first transistors. When the controller issues a data read command, the first block decoder asserts the first block selection signal to allow the first transistors to transfer a first voltage to a selected first word line, and a second voltage to unselected other first word lines. After data is read, the first block decoder continues asserting the first block selection signal, and the driver circuit transfers a third voltage.
    Type: Application
    Filed: September 8, 2020
    Publication date: December 24, 2020
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Masanobu SHIRAKAWA, Marie TAKADA, Tsukasa TOKUTOMI, Yoshihisa KOJIMA, Kiichi TACHI
  • Patent number: 10803953
    Abstract: According to one embodiment, a memory system includes a semiconductor memory and a controller. The semiconductor memory includes: first memory cells, first word lines, a first row decoder, and a driver circuit. The first row decoder includes first transistors capable of coupling the first word lines to first signal lines, and a first block decoder supplying a first block selection signal to the first transistors. When the controller issues a data read command, the first block decoder asserts the first block selection signal to allow the first transistors to transfer a first voltage to a selected first word line, and a second voltage to unselected other first word lines. After data is read, the first block decoder continues asserting the first block selection signal, and the driver circuit transfers a third voltage.
    Type: Grant
    Filed: November 27, 2019
    Date of Patent: October 13, 2020
    Assignee: Toshiba Memory Corporation
    Inventors: Masanobu Shirakawa, Marie Takada, Tsukasa Tokutomi, Yoshihisa Kojima, Kiichi Tachi
  • Publication number: 20200098431
    Abstract: According to one embodiment, a memory system includes a semiconductor memory and a controller. The semiconductor memory includes: first memory cells, first word lines, a first row decoder, and a driver circuit. The first row decoder includes first transistors capable of coupling the first word lines to first signal lines, and a first block decoder supplying a first block selection signal to the first transistors. When the controller issues a data read command, the first block decoder asserts the first block selection signal to allow the first transistors to transfer a first voltage to a selected first word line, and a second voltage to unselected other first word lines. After data is read, the first block decoder continues asserting the first block selection signal, and the driver circuit transfers a third voltage.
    Type: Application
    Filed: November 27, 2019
    Publication date: March 26, 2020
    Applicant: Toshiba Memory Corporation
    Inventors: Masanobu SHIRAKAWA, Marie TAKADA, Tsukasa TOKUTOMI, Yoshihisa KOJIMA, Kiichi TACHI
  • Patent number: 10541030
    Abstract: According to one embodiment, a memory system includes a semiconductor memory and a controller. The semiconductor memory includes: first memory cells, first word lines, a first row decoder, and a driver circuit. The first row decoder includes first transistors capable of coupling the first word lines to first signal lines, and a first block decoder supplying a first block selection signal to the first transistors. When the controller issues a data read command, the first block decoder asserts the first block selection signal to allow the first transistors to transfer a first voltage to a selected first word line, and a second voltage to unselected other first word lines. After data is read, the first block decoder continues asserting the first block selection signal, and the driver circuit transfers a third voltage.
    Type: Grant
    Filed: March 9, 2018
    Date of Patent: January 21, 2020
    Assignee: Toshiba Memory Corporation
    Inventors: Masanobu Shirakawa, Marie Takada, Tsukasa Tokutomi, Yoshihisa Kojima, Kiichi Tachi
  • Publication number: 20190088333
    Abstract: According to one embodiment, a memory system includes a semiconductor memory and a controller. The semiconductor memory includes: first memory cells, first word lines, a first row decoder, and a driver circuit. The first row decoder includes first transistors capable of coupling the first word lines to first signal lines, and a first block decoder supplying a first block selection signal to the first transistors. When the controller issues a data read command, the first block decoder asserts the first block selection signal to allow the first transistors to transfer a first voltage to a selected first word line, and a second voltage to unselected other first word lines. After data is read, the first block decoder continues asserting the first block selection signal, and the driver circuit transfers a third voltage.
    Type: Application
    Filed: March 9, 2018
    Publication date: March 21, 2019
    Applicant: Toshiba Memory Corporation
    Inventors: Masanobu SHIRAKAWA, Marie Takada, Tsukasa Tokutomi, Yoshihisa Kojima, Kiichi Tachi
  • Patent number: 10089241
    Abstract: According to one embodiment, a controller writes either processed data or preprocessing data and flags into each page included in m pages. The processed data is data after first data translation of write data to be written into a relevant page. The preprocessing data is data before the first data translation of the write data to be written into the relevant page. Each of the flag at least represents whether or not the first data translation is performed for write data to be written into the relevant page.
    Type: Grant
    Filed: September 12, 2016
    Date of Patent: October 2, 2018
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Tokumasa Hara, Osamu Torii, Kiichi Tachi, Susumu Tamon, Shigefumi Irieda, Juan Shi, Hironori Uchikawa, Kejen Lin, Akira Yamaga
  • Patent number: 9865338
    Abstract: A controller executes a first data conversion for write data to be written into a first page. The first data conversion includes increasing a ratio of a number of a first value to a total number of pieces of data. The controller executes a second data conversion for write data to be written into a second page. The second data conversion includes increasing a ratio of the number of the second value to the total number of pieces of data.
    Type: Grant
    Filed: March 3, 2016
    Date of Patent: January 9, 2018
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Tokumasa Hara, Kiichi Tachi, Susumu Tamon, Shigefumi Irieda
  • Publication number: 20170262379
    Abstract: According to one embodiment, a controller writes either processed data or preprocessing data and flags into each page included in m pages. The processed data is data after first data translation of write data to be written into a relevant page. The preprocessing data is data before the first data translation of the write data to be written into the relevant page. Each of the flag at least represents whether or not the first data translation is performed for write data to be written into the relevant page.
    Type: Application
    Filed: September 12, 2016
    Publication date: September 14, 2017
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Tokumasa HARA, Osamu Torii, Kiichi Tachi, Susumu Tamon, Shigefumi Irieda, Juan Shi, Hironori Uchikawa, Kejen Lin, Akira Yamaga
  • Publication number: 20170060482
    Abstract: According to one embodiment, a controller executes a first data conversion for write data to be written into a first page. The first data conversion includes increasing a ratio of a number of a first value to a total number of pieces of data. The controller executes a second data conversion for write data to be written into a second page.
    Type: Application
    Filed: March 3, 2016
    Publication date: March 2, 2017
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Tokumasa HARA, Kiichi TACHI, Susumu TAMON, Shigefumi IRIEDA
  • Patent number: 9478301
    Abstract: A semiconductor memory device according to an embodiment includes a control circuit, during data write to a memory cell, sequentially executing: an erasing stage in which a threshold value of the memory cell is transitioned into an erase distribution; a preliminary programming stage in which the threshold value is transitioned into a temporal distribution corresponding to write data; and a main programming stage in which the threshold value is transitioned into a program distribution corresponding to the write data, and the control circuit executing a main reading stage, during the data read to a first memory cell, which includes a main reading step of adjusting a read pass voltage to be applied to a neighboring word line based on a magnitude of a threshold value of the neighboring memory cell, and reading whether the first memory cell is an erase level.
    Type: Grant
    Filed: March 10, 2016
    Date of Patent: October 25, 2016
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventors: Kiichi Tachi, Masanobu Shirakawa, Masaki Yoshimura, Marie Takada, Yoshikazu Harada