Patents by Inventor Yuuichi Kamimuta

Yuuichi Kamimuta 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: 20240096389
    Abstract: A memory cell includes: a core structure extending in a first direction orthogonal to a semiconductor substrate; a semiconductor layer extending in the first direction and in contact with the core structure; an insulating layer extending in the first direction and in contact with the semiconductor layer; a ferroelectric layer extending in the first direction and in contact with the insulating layer; a first electrode extending in a second direction orthogonal to the first direction and in contact with the ferroelectric layer; a second electrode adjacent to the first electrode in the first direction, extending in the second direction, and in contact with the ferroelectric layer; an insulating layer stacked in the first direction and disposed between the first and second electrodes; and an antiferroelectric layer disposed between the first and second electrodes, and in contact with the insulating layer and the ferroelectric layer.
    Type: Application
    Filed: September 1, 2023
    Publication date: March 21, 2024
    Applicant: Kioxia Corporation
    Inventors: Kunifumi SUZUKI, Yuuichi KAMIMUTA
  • Patent number: 11903215
    Abstract: A semiconductor memory device includes: a first semiconductor layer extending in a first direction; a first conductive layer and a second conductive layer that are arranged in the first direction and each opposed to the first semiconductor layer; a first insulating portion disposed between the first semiconductor layer and the first conductive layer, the first insulating portion containing oxygen (O) and hafnium (Hf); a second insulating portion disposed between the first semiconductor layer and the second conductive layer, the second insulating portion containing oxygen (O) and hafnium (Hf); and a first charge storage layer disposed between the first insulating portion and the second insulating portion, the first charge storage layer being spaced from the first conductive layer and the second conductive layer.
    Type: Grant
    Filed: March 14, 2022
    Date of Patent: February 13, 2024
    Assignee: KIOXIA CORPORATION
    Inventors: Kunifumi Suzuki, Yuuichi Kamimuta
  • Patent number: 11871579
    Abstract: A semiconductor memory device of an embodiment includes: a semiconductor layer extending in a first direction; a first gate electrode layer; a second gate electrode layer provided apart from the first gate electrode layer in the first direction; and a gate insulating layer containing oxygen and at least one metal element of hafnium or zirconium, the gate insulating layer including a first region between the first gate electrode layer and the semiconductor layer, a second region between the first gate electrode layer and the second gate electrode layer, and a third region between the second gate electrode layer and the semiconductor layer, the first region including a crystal of an orthorhombic crystal system or a trigonal crystal system as a main constituent substance, and a distance between the second region and the semiconductor layer being larger than a distance between the first region and the semiconductor layer.
    Type: Grant
    Filed: September 10, 2021
    Date of Patent: January 9, 2024
    Assignee: Kioxia Corporation
    Inventors: Kunifumi Suzuki, Yuuichi Kamimuta
  • Patent number: 11672129
    Abstract: A memory device according to an embodiment includes a first conductive layer; a second conductive layer; a ferroelectric layer provided between the first conductive layer and the second conductive layer and containing hafnium oxide; a paraelectric layer provided between the first conductive layer and the ferroelectric layer and containing a first oxide; and an oxide layer provided between the paraelectric layer and the ferroelectric layer and containing a second oxide having an oxygen area density lower than an oxygen area density of the first oxide.
    Type: Grant
    Filed: January 13, 2021
    Date of Patent: June 6, 2023
    Assignee: Kioxia Corporation
    Inventors: Shoichi Kabuyanagi, Yuuichi Kamimuta, Masumi Saitoh, Marina Yamaguchi
  • Publication number: 20230170018
    Abstract: According to one embodiment, a memory device includes a memory cell including a resistance change memory portion and a switching portion, and a voltage applying circuit carrying out, at a time of writing data to the memory cell, an operation of applying a voltage of a first polarity to the memory cell and applying a first voltage to the memory cell, an operation of applying a voltage of a second polarity to the memory cell and applying a second voltage to the memory cell, an operation of applying a voltage of the first polarity to the memory cell and applying a third voltage to the memory cell, or an operation of applying a voltage of the second polarity to the memory cell and applying a fourth voltage to the memory cell.
    Type: Application
    Filed: June 15, 2022
    Publication date: June 1, 2023
    Inventors: Kunifumi SUZUKI, Yuuichi KAMIMUTA
  • Publication number: 20230084292
    Abstract: A semiconductor memory device includes: a first semiconductor layer extending in a first direction; a first conductive layer and a second conductive layer that are arranged in the first direction and each opposed to the first semiconductor layer; a first insulating portion disposed between the first semiconductor layer and the first conductive layer, the first insulating portion containing oxygen (O) and hafnium (Hf); a second insulating portion disposed between the first semiconductor layer and the second conductive layer, the second insulating portion containing oxygen (O) and hafnium (Hf); and a first charge storage layer disposed between the first insulating portion and the second insulating portion, the first charge storage layer being spaced from the first conductive layer and the second conductive layer.
    Type: Application
    Filed: March 14, 2022
    Publication date: March 16, 2023
    Applicant: KIOXIA CORPORATION
    Inventors: Kunifumi SUZUKI, Yuuichi KAMIMUTA
  • Publication number: 20220399489
    Abstract: A storage device 10 includes a phase change layer 40 containing tellurium, and a diffusion layer 50 containing at least one of germanium, silicon, carbon, tin, aluminum, gallium, and indium and disposed at a position adjacent to the phase change layer 40. The phase change layer 40 is capable of changing between a first state and a second state different from each other in electric resistance. The phase change layer 40 is in a crystal state in any of the first state and the second state. A length of the diffusion layer 50 in a direction orthogonal to a z direction is shorter than a length of the phase change layer 40 in the direction orthogonal to the z direction.
    Type: Application
    Filed: December 13, 2021
    Publication date: December 15, 2022
    Applicant: Kioxia Corporation
    Inventors: Kunifumi SUZUKI, Yuuichi KAMIMUTA
  • Publication number: 20220399488
    Abstract: A memory device includes a first interconnect layer, a second interconnect layer, a phase-change layer, and an adjacent layer. The phase-change layer is disposed between the first interconnect layer and the second interconnect layer and configured to reversibly transition between a crystalline state and an amorphous state. The adjacent layer contacts the phase-change layer and comprises tellurium and at least one of titanium, zirconium, or hafnium.
    Type: Application
    Filed: January 28, 2022
    Publication date: December 15, 2022
    Inventors: Kunifumi SUZUKI, Yuuichi KAMIMUTA
  • Publication number: 20220302169
    Abstract: A semiconductor storage device includes a channel layer extending along a first direction and including titanium oxide, an electrode layer extending along a second direction crossing the first direction, and a ferroelectric layer between the channel layer and the electrode layer and including titanium.
    Type: Application
    Filed: August 25, 2021
    Publication date: September 22, 2022
    Inventors: Keisuke TAKAGI, Kazuhiro MATSUO, Kunifumi SUZUKI, Yuuichi KAMIMUTA, Taro SHIOKAWA, Masumi SAITOH, Yuta KAMIYA, Kota TAKAHASHI
  • Publication number: 20220302170
    Abstract: A semiconductor memory device of an embodiment includes: a semiconductor layer extending in a first direction; a first gate electrode layer; a second gate electrode layer provided apart from the first gate electrode layer in the first direction; and a gate insulating layer containing oxygen and at least one metal element of hafnium or zirconium, the gate insulating layer including a first region between the first gate electrode layer and the semiconductor layer, a second region between the first gate electrode layer and the second gate electrode layer, and a third region between the second gate electrode layer and the semiconductor layer, the first region including a crystal of an orthorhombic crystal system or a trigonal crystal system as a main constituent substance, and a distance between the second region and the semiconductor layer being larger than a distance between the first region and the semiconductor layer.
    Type: Application
    Filed: September 10, 2021
    Publication date: September 22, 2022
    Applicant: Kioxia Corporation
    Inventors: Kunifumi SUZUKI, Yuuichi KAMIMUTA
  • Patent number: 11437403
    Abstract: Provided is a storage device according to an embodiment including: a stacked body including gate electrode layers stacked in a first direction; a semiconductor layer provided in the stacked body and extending in the first direction; and a gate insulating film provided between the semiconductor layer and the gate electrode layer, the gate insulating film having a first region disposed between the gate electrode layer and the semiconductor layer and a second region disposed between the two first regions adjacent to each other in the first direction, the gate insulating film containing a hafnium oxide, in which a first thickness of the first region in the second direction from the semiconductor layer toward the gate electrode layer is smaller than a second thickness of the second region in the second direction.
    Type: Grant
    Filed: June 16, 2020
    Date of Patent: September 6, 2022
    Assignee: Kioxia Corporation
    Inventors: Keiko Sakuma, Akio Kaneko, Hidenori Miyagawa, Yuuichi Kamimuta
  • Patent number: 11380773
    Abstract: A semiconductor memory device of an embodiment includes a semiconductor layer; a gate electrode including a first portion, a second portion provided to be spaced apart from the first portion, and a spacer provided between the first portion and the second portion; and a first insulating layer provided between the semiconductor layer and the gate electrode and including a first region containing a ferroelectric, a ferrielectric, or an anti-ferroelectric, a second region containing a ferroelectric, a ferrielectric, or an anti-ferroelectric, and a boundary region provided between the first region and the second region. The first region is positioned between the first portion and the semiconductor layer, the second region is positioned between the second portion and the semiconductor layer, the boundary region is positioned between the spacer and the semiconductor layer, and the boundary region has a chemical composition different from that of the spacer.
    Type: Grant
    Filed: October 31, 2019
    Date of Patent: July 5, 2022
    Assignee: Kioxia Corporation
    Inventors: Tsunehiro Ino, Yusuke Higashi, Toshinori Numata, Yuuichi Kamimuta
  • Publication number: 20210134814
    Abstract: A memory device according to an embodiment includes a first conductive layer; a second conductive layer; a ferroelectric layer provided between the first conductive layer and the second conductive layer and containing hafnium oxide; a paraelectric layer provided between the first conductive layer and the ferroelectric layer and containing a first oxide; and an oxide layer provided between the paraelectric layer and the ferroelectric layer and containing a second oxide having an oxygen area density lower than an oxygen area density of the first oxide.
    Type: Application
    Filed: January 13, 2021
    Publication date: May 6, 2021
    Applicant: Toshiba Memory Corporation
    Inventors: Shoichi Kabuyanagi, Yuuichi Kamimuta, Masumi Saitoh, Marina Yamaguchi
  • Publication number: 20210082957
    Abstract: Provided is a storage device according to an embodiment including: a stacked body including gate electrode layers stacked in a first direction; a semiconductor layer provided in the stacked body and extending in the first direction; and a gate insulating film provided between the semiconductor layer and the gate electrode layer, the gate insulating film having a first region disposed between the gate electrode layer and the semiconductor layer and a second region disposed between the two first regions adjacent to each other in the first direction, the gate insulating film containing a hafnium oxide, in which a first thickness of the first region in the second direction from the semiconductor layer toward the gate electrode layer is smaller than a second thickness of the second region in the second direction.
    Type: Application
    Filed: June 16, 2020
    Publication date: March 18, 2021
    Applicant: Kioxia Corporation
    Inventors: Keiko SAKUMA, Akio Kaneko, Hidenori Miyagawa, Yuuichi Kamimuta
  • Patent number: 10923500
    Abstract: A memory device according to an embodiment includes a first conductive layer, a second conductive layer, and a first layer provided between the first conductive layer and the second conductive layer and containing aluminum oxide that contains at least one first element selected from the group consisting of magnesium (Mg), silicon (Si), hafnium (Hf), tungsten (W), and ruthenium (Ru), and the aluminum oxide is a ferroelectric.
    Type: Grant
    Filed: March 21, 2019
    Date of Patent: February 16, 2021
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Tsunehiro Ino, Yuuichi Kamimuta
  • Patent number: 10923486
    Abstract: A memory device according to an embodiment includes a first conductive layer; a second conductive layer; a ferroelectric layer provided between the first conductive layer and the second conductive layer and containing hafnium oxide; a paraelectric layer provided between the first conductive layer and the ferroelectric layer and containing a first oxide; and an oxide layer provided between the paraelectric layer and the ferroelectric layer and containing a second oxide having an oxygen area density lower than an oxygen area density of the first oxide.
    Type: Grant
    Filed: February 26, 2018
    Date of Patent: February 16, 2021
    Assignee: Toshiba Memory Corporation
    Inventors: Shoichi Kabuyanagi, Yuuichi Kamimuta, Masumi Saitoh, Marina Yamaguchi
  • Patent number: 10861528
    Abstract: A semiconductor memory device according to one embodiment includes: a memory cell, the memory cell including a ferroelectric film; and a control circuit controlling the memory cell. Additionally, the control circuit determining whether the number of times of executions of a write process or an erase process on the memory cell has reached a predetermined number of times; and, if the number of times of executions has reached the predetermined number of times, executing a voltage application process in which a first voltage of a first polarity and a second voltage of a second polarity opposite to the first polarity are applied to the ferroelectric film.
    Type: Grant
    Filed: March 26, 2020
    Date of Patent: December 8, 2020
    Assignee: Toshiba Memory Corporation
    Inventors: Yusuke Higashi, Yuuichi Kamimuta, Tsunehiro Ino
  • Patent number: 10833098
    Abstract: According to one embodiment, a semiconductor memory device includes a first conductive member, a first semiconductor member, and a first stacked member provided between the first conductive member and the first semiconductor member. The first stacked member includes a first insulating film, a second insulating film provided between the first insulating film and the first semiconductor member, first and second layers. The first layer includes aluminum and nitrogen and is provided between the first and second insulating films. A first thickness of the first layer along a first direction is 3 nm or less. The first direction is from the first semiconductor member toward the first conductive member. The second layer contacts the first layer, includes silicon and nitrogen, and is provided at one of a position between the first layer and the second insulating film or a position between the first layer and the first insulating film.
    Type: Grant
    Filed: March 12, 2019
    Date of Patent: November 10, 2020
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Akira Takashima, Tsunehiro Ino, Yuuichi Kamimuta, Ayaka Suko
  • Publication number: 20200227108
    Abstract: A semiconductor memory device according to one embodiment includes: a memory cell, the memory cell including a ferroelectric film; and a control circuit controlling the memory cell. Additionally, the control circuit determining whether the number of times of executions of a write process or an erase process on the memory cell has reached a predetermined number of times; and, if the number of times of executions has reached the predetermined number of times, executing a voltage application process in which a first voltage of a first polarity and a second voltage of a second polarity opposite to the first polarity are applied to the ferroelectric film.
    Type: Application
    Filed: March 26, 2020
    Publication date: July 16, 2020
    Applicant: Toshiba Memory Corporation
    Inventors: Yusuke Higashi, Yuuichi Kamimuta, Tsunehiro Ino
  • Patent number: 10636468
    Abstract: A semiconductor memory device according to one embodiment includes: a memory cell, the memory cell including a ferroelectric film; and a control circuit controlling the memory cell. Additionally, the control circuit determining whether the number of times of executions of a write process or an erase process on the memory cell has reached a predetermined number of times; and, if the number of times of executions has reached the predetermined number of times, executing a voltage application process in which a first voltage of a first polarity and a second voltage of a second polarity opposite to the first polarity are applied to the ferroelectric film.
    Type: Grant
    Filed: August 27, 2018
    Date of Patent: April 28, 2020
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Yusuke Higashi, Yuuichi Kamimuta, Tsunehiro Ino