Patents by Inventor Hidehiro Shiga

Hidehiro Shiga 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: 10910059
    Abstract: According to the present embodiment, a nonvolatile semiconductor memory device includes a memory string group including k stacked memory strings, each of the memory strings including a plurality of nonvolatile memory cells connected in series, a selection transistor group including k selection transistors, each of the k selection transistors corresponding to each of the k memory strings respectively, the selection transistor group divided into n selection transistor sub-groups, each of the n selection transistor sub-groups including k/n selection transistors, n bit lines arranged in parallel to each of the k memory strings, and n bit line contacts arranged perpendicularly, each of the n bit line contacts connected to each of the n bit lines, respectively, each of the n bit line contacts connected to the k/n selection transistors belonging to the each of the n selection transistor sub-group respectively.
    Type: Grant
    Filed: September 9, 2019
    Date of Patent: February 2, 2021
    Assignee: Toshiba Memory Corporation
    Inventor: Hidehiro Shiga
  • Patent number: 10896733
    Abstract: A semiconductor memory device comprises: a memory transistor; a first wiring connected to a gate electrode of the memory transistor; and a control device that executes a read operation to read data of the memory transistor and a write operation to write data in the memory transistor. In the read operation or the write operation, the control device: increases a voltage of the first wiring to a first voltage from a first timing to a second timing; and adjusts a length from the first timing to the second timing corresponding to at least one of a voltage of the first wiring, a current of the first wiring, and an amount of charge flowed through the first wiring.
    Type: Grant
    Filed: September 6, 2019
    Date of Patent: January 19, 2021
    Assignee: Toshiba Memory Corporation
    Inventors: Keita Kimura, Hidehiro Shiga
  • Publication number: 20200395084
    Abstract: A semiconductor storage device includes a first memory cell and a second memory cell which are connected to each other in series, a first word line which is connected to the first memory cell, a second word line which is connected to the second memory cell, and a control circuit. The control circuit is configured to charge a first node while applying a second voltage to the second word line and a first voltage to the first word line, to charge a second node on the basis of a voltage of the charged first node, to discharge the second node while applying the second voltage to the second word line and a third voltage to the first word line, and to read data from the first memory cell on the basis of voltages of the charged and discharged second node.
    Type: Application
    Filed: February 26, 2020
    Publication date: December 17, 2020
    Inventors: Rieko FUNATSUKI, Takashi MAEDA, Hidehiro SHIGA, Hiroshi MAEJIMA
  • Patent number: 10803950
    Abstract: According to one embodiment, a memory controller transmits a first instruction to a memory device. The memory device includes cell transistors; word lines coupled to gates of the cell transistors; a first data latch; and a second latch. The first instruction instructs application of a positive voltage to one of the word lines. The memory controller transmits a second instruction after the transmission of the first instruction and before transmitting a third instruction. The third instruction instructs output of data from the memory device. The second instruction is different from the third instruction and a fourth instruction instructing copy of data from the first data latch to the second data latch.
    Type: Grant
    Filed: May 23, 2019
    Date of Patent: October 13, 2020
    Assignee: Toshiba Memory Corporation
    Inventors: Yasuhiro Shimura, Tomoki Higashi, Sumito Ohtsuki, Junichi Kijima, Keisuke Yonehama, Shinichi Oosera, Yuki Kanamori, Hidehiro Shiga, Koki Ueno
  • Publication number: 20200294594
    Abstract: A semiconductor memory device comprises: a memory transistor; a first wiring connected to a gate electrode of the memory transistor; and a control device that executes a read operation to read data of the memory transistor and a write operation to write data in the memory transistor. In the read operation or the write operation, the control device: increases a voltage of the first wiring to a first voltage from a first timing to a second timing; and adjusts a length from the first timing to the second timing corresponding to at least one of a voltage of the first wiring, a current of the first wiring, and an amount of charge flowed through the first wiring.
    Type: Application
    Filed: September 6, 2019
    Publication date: September 17, 2020
    Applicant: Toshiba Memory Corporation
    Inventors: Keita KIMURA, Hidehiro SHIGA
  • Publication number: 20200294595
    Abstract: According to the present embodiment, a nonvolatile semiconductor memory device includes a memory string group including k stacked memory strings, each of the memory strings including a plurality of nonvolatile memory cells connected in series, a selection transistor group including k selection transistors, each of the k selection transistors corresponding to each of the k memory strings respectively, the selection transistor group divided into n selection transistor sub-groups, each of the n selection transistor sub-groups including k/n selection transistors, n bit lines arranged in parallel to each of the k memory strings, and n bit line contacts arranged perpendicularly, each of the n bit line contacts connected to each of the n bit lines, respectively, each of the n bit line contacts connected to the k/n selection transistors belonging to the each of the n selection transistor sub-group respectively.
    Type: Application
    Filed: September 9, 2019
    Publication date: September 17, 2020
    Applicant: Toshiba Memory Corporation
    Inventor: Hidehiro SHIGA
  • Publication number: 20190279716
    Abstract: According to one embodiment, a memory controller transmits a first instruction to a memory device. The memory device includes cell transistors; word lines coupled to gates of the cell transistors; a first data latch; and a second latch. The first instruction instructs application of a positive voltage to one of the word lines. The memory controller transmits a second instruction after the transmission of the first instruction and before transmitting a third instruction. The third instruction instructs output of data from the memory device. The second instruction is different from the third instruction and a fourth instruction instructing copy of data from the first data latch to the second data latch.
    Type: Application
    Filed: May 23, 2019
    Publication date: September 12, 2019
    Applicant: Toshiba Memory Corporation
    Inventors: Yasuhiro Shimura, Tomoki Higashi, Sumito Ohtsuki, Junichi Kijima, Keisuke Yonehama, Shinichi Oosera, Yuki Kanamori, Hidehiro Shiga, Koki Ueno
  • Patent number: 10347338
    Abstract: According to one embodiment, a memory controller transmits a first instruction to a memory device. The memory device includes cell transistors; word lines coupled to gates of the cell transistors; a first data latch; and a second latch. The first instruction instructs application of a positive voltage to one of the word lines. The memory controller transmits a second instruction after the transmission of the first instruction and before transmitting a third instruction. The third instruction instructs output of data from the memory device. The second instruction is different from the third instruction and a fourth instruction instructing copy of data from the first data latch to the second data latch.
    Type: Grant
    Filed: September 8, 2017
    Date of Patent: July 9, 2019
    Assignee: Toshiba Memory Corporation
    Inventors: Yasuhiro Shimura, Tomoki Higashi, Sumito Ohtsuki, Junichi Kijima, Keisuke Yonehama, Shinichi Oosera, Yuki Kanamori, Hidehiro Shiga, Koki Ueno
  • Publication number: 20180268906
    Abstract: According to one embodiment, a memory controller transmits a first instruction to a memory device. The memory device includes cell transistors; word lines coupled to gates of the cell transistors; a first data latch; and a second latch. The first instruction instructs application of a positive voltage to one of the word lines. The memory controller transmits a second instruction after the transmission of the first instruction and before transmitting a third instruction. The third instruction instructs output of data from the memory device. The second instruction is different from the third instruction and a fourth instruction instructing copy of data from the first data latch to the second data latch.
    Type: Application
    Filed: September 8, 2017
    Publication date: September 20, 2018
    Applicant: Toshiba Memory Corporation
    Inventors: Yasuhiro SHIMURA, Tomoki HIGASHI, Sumito OHTSUKI, Junichi KIJIMA, Keisuke YONEHAMA, Shinichi OOSERA, Yuki KANAMORI, Hidehiro SHIGA, Koki UENO
  • Patent number: 9817598
    Abstract: A memory device includes a first memory string including a first selection transistor and a first memory cell, a second memory string including a second selection transistor and a second memory cell, a bit line electrically connected to the first memory string and the second memory string, and a control circuit configured to perform a collective write operation on the first memory cell and the second memory cell by applying a voltage to turn on the first transistor, a voltage to turn on the second transistor, and then a program voltage at the same time to gates of the first and second memory cells.
    Type: Grant
    Filed: November 8, 2016
    Date of Patent: November 14, 2017
    Assignee: Toshiba Memory Corporation
    Inventors: Hidehiro Shiga, Masanobu Shirakawa, Tokumasa Hara
  • Patent number: 9805804
    Abstract: A semiconductor memory device includes a memory cell array including a plurality of groups of memory cells above a substrate, the groups including a first group and a second group, each of the first and second groups including a first memory string and a second memory string, the first memory string including first memory cells that are disposed in a first layer, the second memory string including second memory cell that are disposed in a second layer above the first layer, and a controller configured to perform an erasing operation on the memory cells, the erasing operation including a verifying operation on the memory cells to determine on a layer by layer basis whether the memory cells failed to erase data stored therein.
    Type: Grant
    Filed: May 27, 2016
    Date of Patent: October 31, 2017
    Assignee: Toshiba Memory Corporation
    Inventors: Hidehiro Shiga, Masanobu Shirakawa, Kenichi Abe
  • Patent number: 9767908
    Abstract: A non-volatile semiconductor memory device includes a first memory cell above a substrate and electrically connected to a first word line, a second memory cell above the first memory cell and electrically connected to a second word line, and a controller. The controller is configured to execute a write operation that includes a first step in which a first voltage is applied to a selected word line and to a non-selected word line, a second step after the first step in which a program voltage is applied to the selected word line, and a third step after the second step in which a second voltage higher than the first voltage is applied to the non-selected word line. A time period between a start of the second step and a start of the third step is different depending on whether the first or second memory cell is being written.
    Type: Grant
    Filed: February 26, 2016
    Date of Patent: September 19, 2017
    Assignee: Toshiba Memory Corporation
    Inventors: Sanad Bushnaq, Masanobu Shirakawa, Hidehiro Shiga
  • Publication number: 20170255410
    Abstract: A memory device includes a first memory string including a first selection transistor and a first memory cell, a second memory string including a second selection transistor and a second memory cell, a bit line electrically connected to the first memory string and the second memory string, and a control circuit configured to perform a collective write operation on the first memory cell and the second memory cell by applying a voltage to turn on the first transistor, a voltage to turn on the second transistor, and then a program voltage at the same time to gates of the first and second memory cells.
    Type: Application
    Filed: November 8, 2016
    Publication date: September 7, 2017
    Inventors: Hidehiro SHIGA, Masanobu SHIRAKAWA, Tokumasa HARA
  • Patent number: 9704584
    Abstract: A semiconductor memory device includes a first block including a first memory string that includes a first memory cell and a first select transistor, a second block including a second memory string that includes a second memory cell and a second select transistor, a source line that is connected to the first memory string and the second memory string, and a controller that applies a source line voltage to the source line and a first voltage to a gate of the second select transistor during a program operation in which data is written to the first memory cell, the first voltage being greater than ground voltage and less than or equal to the source line voltage.
    Type: Grant
    Filed: March 3, 2016
    Date of Patent: July 11, 2017
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Maejima, Yuya Suzuki, Hidehiro Shiga, Tomonori Kurosawa
  • Publication number: 20160276032
    Abstract: A semiconductor memory device includes a memory cell array including a plurality of groups of memory cells above a substrate, the groups including a first group and a second group, each of the first and second groups including a first memory string and a second memory string, the first memory string including first memory cells that are disposed in a first layer, the second memory string including second memory cell that are disposed in a second layer above the first layer, and a controller configured to perform an erasing operation on the memory cells, the erasing operation including a verifying operation on the memory cells to determine on a layer by layer basis whether the memory cells failed to erase data stored therein.
    Type: Application
    Filed: May 27, 2016
    Publication date: September 22, 2016
    Inventors: Hidehiro SHIGA, Masanobu SHIRAKAWA, Kenichi ABE
  • Publication number: 20160267990
    Abstract: A non-volatile semiconductor memory device includes a first memory cell above a substrate and electrically connected to a first word line, a second memory cell above the first memory cell and electrically connected to a second word line, and a controller. The controller is configured to execute a write operation that includes a first step in which a first voltage is applied to a selected word line and to a non-selected word line, a second step after the first step in which a program voltage is applied to the selected word line, and a third step after the second step in which a second voltage higher than the first voltage is applied to the non-selected word line. A time period between a start of the second step and a start of the third step is different depending on whether the first or second memory cell is being written.
    Type: Application
    Filed: February 26, 2016
    Publication date: September 15, 2016
    Inventors: Sanad BUSHNAQ, Masanobu SHIRAKAWA, Hidehiro SHIGA
  • Publication number: 20160267992
    Abstract: A semiconductor memory device includes a first block including a first memory string that includes a first memory cell and a first select transistor, a second block including a second memory string that includes a second memory cell and a second select transistor, a source line that is connected to the first memory string and the second memory string, and a controller that applies a source line voltage to the source line and a first voltage to a gate of the second select transistor during a program operation in which data is written to the first memory cell, the first voltage being greater than ground voltage and less than or equal to the source line voltage.
    Type: Application
    Filed: March 3, 2016
    Publication date: September 15, 2016
    Inventors: Hiroshi MAEJIMA, Yuya SUZUKI, Hidehiro SHIGA, Tomonori KUROSAWA
  • Patent number: 9355731
    Abstract: A semiconductor memory device includes a memory cell array including a plurality of groups of memory cells above a substrate, the groups including a first group and a second group, each of the first and second groups including a first memory string and a second memory string, the first memory string including first memory cells that are disposed in a first layer, the second memory string including second memory cell that are disposed in a second layer above the first layer, and a controller configured to perform an erasing operation on the memory cells, the erasing operation including a verifying operation on the memory cells to determine on a layer by layer basis whether the memory cells failed to erase data stored therein.
    Type: Grant
    Filed: March 3, 2015
    Date of Patent: May 31, 2016
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hidehiro Shiga, Masanobu Shirakawa, Kenichi Abe
  • Patent number: 9349464
    Abstract: A non-volatile semiconductor device includes first and second selecting transistors; multiple memory cells that are stacked above the substrate; multiple word lines that are connected to control gates of the multiple memory cells; selecting gate lines that are each connected to a gate of one of the selecting transistors; a bit line connected to the first selecting transistor; a source line connected to the second selecting transistor; and a control circuit configured to execute an erasing loop that includes an erase operation and a verifying operation. The control circuit increases an erasing voltage in accordance with the number of times the erasing loop is repeated.
    Type: Grant
    Filed: January 28, 2015
    Date of Patent: May 24, 2016
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hidehiro Shiga, Masanobu Shirakawa
  • Publication number: 20160064088
    Abstract: A semiconductor memory device includes a memory cell array including a plurality of groups of memory cells above a substrate, the groups including a first group and a second group, each of the first and second groups including a first memory string and a second memory string, the first memory string including first memory cells that are disposed in a first layer, the second memory string including second memory cell that are disposed in a second layer above the first layer, and a controller configured to perform an erasing operation on the memory cells, the erasing operation including a verifying operation on the memory cells to determine on a layer by layer basis whether the memory cells failed to erase data stored therein.
    Type: Application
    Filed: March 3, 2015
    Publication date: March 3, 2016
    Inventors: Hidehiro SHIGA, Masanobu SHIRAKAWA, Kenichi ABE