Patents by Inventor Tatsuo OGURA

Tatsuo OGURA 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: 20250095743
    Abstract: A semiconductor memory device includes: a first conductive layer; and a second conductive layer adjacent to the first conductive layer. Write loops each include: a first program operation that applies the first conductive layer with a program voltage and applies a bit line with a first bit line voltage; and a second program operation that applies the first conductive layer with the program voltage and applies the bit line with a second bit line voltage larger than the first bit line voltage. The write operation includes a state judging operation that judges whether a memory cell corresponding to the semiconductor layer and the second conductive layer has been controlled to a Low-state, or not. When the memory cell has been controlled to the Low-state, the first program operation is executed, and when the memory cell has not been controlled to the Low-state, the second program operation is executed.
    Type: Application
    Filed: September 10, 2024
    Publication date: March 20, 2025
    Applicant: Kioxia Corporation
    Inventors: Tatsuo OGURA, Masaki KONDO, Takashi MAEDA
  • Publication number: 20250098165
    Abstract: In one embodiment, a semiconductor memory device includes a stacked body of a first conductive films and first insulation films alternately stacked with each other in a first direction. A plurality of columnar bodies is in the stacked body. Each columnar body includes a first semiconductor part extending in the first direction, a first insulation part between the first semiconductor part and the stacked body, a second insulation part between the first insulation part and the stacked body, third insulation parts between the second insulation part and the first conductive films, and fourth insulation parts between the second insulation part and the first insulation films. Each second insulation part has first portions between the first insulation part and the first conductive films and second portions between the first insulation part and the first insulation film. The second portions are thinner than the first portions in a second direction.
    Type: Application
    Filed: September 13, 2024
    Publication date: March 20, 2025
    Inventors: Fumie KIKUSHIMA, Michiko ISHIDA, Yosuke MURAKAMI, Hideomi AOIKE, Tatsuya ISHIKAWA, Ryo YOUGAUCHI, Tatsuo OGURA
  • Publication number: 20210272640
    Abstract: A semiconductor memory device includes a plurality of conductive layers, a semiconductor layer opposed to the plurality of conductive layers, and an electric charge accumulation portion disposed between the semiconductor layer and the plurality of conductive layers. The electric charge accumulation portion includes a plurality of first electric charge accumulation portions opposed to the plurality of conductive layers, and a plurality of second electric charge accumulation portions disposed in positions different from the plurality of first electric charge accumulation portions. A distance between the first electric charge accumulation portion and the semiconductor layer is smaller than a distance between the second electric charge accumulation portion and the semiconductor layer. A distance between the second electric charge accumulation portion and the conductive layers is smaller than a distance between the first electric charge accumulation portion and the conductive layers.
    Type: Application
    Filed: September 8, 2020
    Publication date: September 2, 2021
    Applicant: KIOXIA CORPORATION
    Inventors: Tatsuo OGURA, Takashi KURUSU, Muneyuki TSUDA, Hiroshi TAKEDA, Nayuta KARIYA
  • Patent number: 10839911
    Abstract: A semiconductor memory device includes a plurality of memory cells, a plurality of word lines connected to the plurality of memory cells, respectively, and a row control circuit. The row control circuit is configured to apply a program voltage to a first word line among the word lines while stepping up a value of the program voltage; apply a first pass voltage to a second word line among the word lines different from the first word line when applying the program voltage having a voltage value equal to or greater than a predetermined voltage value to the first word line; and apply a second pass voltage having a voltage value higher than the first pass voltage to the second word line when applying the program voltage having a voltage value less than the predetermined voltage value to the first word line.
    Type: Grant
    Filed: February 25, 2019
    Date of Patent: November 17, 2020
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Tatsuo Ogura, Hideto Horii
  • Publication number: 20200090755
    Abstract: A semiconductor memory device includes a plurality of memory cells, a plurality of word lines connected to the plurality of memory cells, respectively, and a row control circuit. The row control circuit is configured to apply a program voltage to a first word line among the word lines while stepping up a value of the program voltage; apply a first pass voltage to a second word line among the word lines different from the first word line when applying the program voltage having a voltage value equal to or greater than a predetermined voltage value to the first word line; and apply a second pass voltage having a voltage value higher than the first pass voltage to the second word line when applying the program voltage having a voltage value less than the predetermined voltage value to the first word line.
    Type: Application
    Filed: February 25, 2019
    Publication date: March 19, 2020
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Tatsuo OGURA, Hideto HORII