Patents by Inventor Eiji Kitagawa

Eiji Kitagawa 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: 20220093848
    Abstract: According to one embodiment, a magnetic memory device includes a first magnetic layer, a second magnetic layer and a third magnetic layer having a fixed magnetization direction antiparallel to a magnetization direction of the second magnetic layer, first, second and third nonmagnetic layers. The firs nonmagnetic layer is between the first and second magnetic layers, the second magnetic layer is between the first nonmagnetic layer and the third magnetic layer, the third magnetic layer is between the second magnetic layer and the second nonmagnetic layer, the third nonmagnetic layer is between the second and the third magnetic layers, the third magnetic layer contains Co and Pt, and the second nonmagnetic layer contains at least one of Mo and W.
    Type: Application
    Filed: September 10, 2021
    Publication date: March 24, 2022
    Applicant: Kioxia Corporation
    Inventors: Eiji KITAGAWA, Youngmin EEH, Tadaaki OIKAWA, Kazuya SAWADA, Taiga ISODA
  • Publication number: 20220085279
    Abstract: According to one embodiment, a magnetic memory device includes a magnetoresistance effect element. The magnetoresistance effect element includes a first ferromagnetic layer, a second ferromagnetic layer, a third ferromagnetic layer, a first non-magnetic layer between the first ferromagnetic layer and the second ferromagnetic layer, and a second non-magnetic layer between the second ferromagnetic layer and the third ferromagnetic layer. The second ferromagnetic layer is between the first ferromagnetic layer and the third ferromagnetic layer. The first non-magnetic layer contains an oxide containing magnesium (Mg). The third ferromagnetic layer contains silicon (Si) or germanium (Ge).
    Type: Application
    Filed: September 10, 2021
    Publication date: March 17, 2022
    Applicant: Kioxia Corporation
    Inventors: Kazuya SAWADA, Young Min EEH, Tadaaki OIKAWA, Eiji KITAGAWA, Taiga ISODA
  • Publication number: 20220085103
    Abstract: According to one embodiment, a magnetic memory device includes: a first interconnect extending in a first direction; a switching element provided on the first interconnect; a conductor provided on the switching element; a magnetoresistance effect element provided on the conductor; and an insulating layer provided in a layer in which the switching element is provided. An area of a first principal surface of the switching element that faces the conductor is smaller than that of a second principal surface of the conductor that faces the switching element.
    Type: Application
    Filed: March 12, 2021
    Publication date: March 17, 2022
    Applicant: Kioxia Corporation
    Inventors: Kenichi YOSHINO, Eiji KITAGAWA, Naoki AKIYAMA
  • Patent number: 11217288
    Abstract: According to one embodiment, a magnetic device includes: a first magnetic material provided above a substrate; a second magnetic material provided between the substrate and the first magnetic material; a nonmagnetic material provided between the first magnetic material and the second magnetic material; a first layer provided between the substrate and the second magnetic material and including an amorphous layer; and a second layer provided between the amorphous layer and the second magnetic material and including a crystal layer.
    Type: Grant
    Filed: September 10, 2019
    Date of Patent: January 4, 2022
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Kazuya Sawada, Young Min Eeh, Tadaaki Oikawa, Kenichi Yoshino, Eiji Kitagawa, Taiga Isoda
  • Patent number: 11127445
    Abstract: According to one embodiment, a magnetic device includes a magnetic tunnel junction element, the magnetic tunnel junction element comprising: a first structure having ferromagnetism; a second structure having ferromagnetism; and a first nonmagnet provided between the first structure and the second structure; wherein: the first structure and the second structure are antiferromagnetically coupled via the first nonmagnet; and the first structure includes a first ferromagnetic nitride.
    Type: Grant
    Filed: March 13, 2019
    Date of Patent: September 21, 2021
    Assignees: TOSHIBA MEMORY CORPORATION, SK HYNIX INC.
    Inventors: Young Min Eeh, Taeyoung Lee, Kazuya Sawada, Eiji Kitagawa, Taiga Isoda, Tadaaki Oikawa, Kenichi Yoshino
  • Publication number: 20210287755
    Abstract: A semiconductor memory device includes: a first memory cell and switching element coupled in series between a first and second interconnect; a second memory cell and switching element coupled in series between the first and a third interconnect; a third memory cell and switching element coupled in series between the first and a fourth interconnect; and a control circuit. The control circuit is configured to: in a first operation on the first memory cell, upon receipt of a first command, apply a third voltage between the first and second voltage to the third and fourth interconnect; and upon receipt of a second command, apply the first and third voltage to the fourth and third interconnect, respectively.
    Type: Application
    Filed: September 9, 2020
    Publication date: September 16, 2021
    Applicant: Kioxia Corporation
    Inventors: Hisanori AIKAWA, Eiji KITAGAWA
  • Publication number: 20210288240
    Abstract: A magnetic memory device includes a magnetoresistance effect element including a first, second, and third ferromagnetic layer, a first non-magnetic layer between the first and second ferromagnetic layer, and a second non-magnetic layer between the second and third ferromagnetic layer. The second ferromagnetic layer is between the first and third ferromagnetic layer. The third ferromagnetic layer includes a fourth ferromagnetic layer in contact with the second non-magnetic layer, a third non-magnetic layer, and a fourth non-magnetic layer between the fourth ferromagnetic layer and the third non-magnetic layer. The first non-magnetic layer includes an oxide including magnesium (Mg). A melting point of the fourth non-magnetic layer is higher than the third non-magnetic layer.
    Type: Application
    Filed: September 9, 2020
    Publication date: September 16, 2021
    Applicant: Kioxia Corporation
    Inventors: Kazuya SAWADA, Young Min EEH, Tadaaki OIKAWA, Eiji KITAGAWA, Taiga ISODA
  • Publication number: 20210287728
    Abstract: According to one embodiment, a memory device includes: a first ferromagnetic layer; an insulating layer above the first ferromagnetic layer; a second ferromagnetic layer above the insulating layer; a capping layer on an upper surface of the second ferromagnetic layer; and an electrode on an upper surface of the capping layer. The second ferromagnetic layer includes iron atoms. The capping layer includes one or more elements identical to one or more elements in the second ferromagnetic layer. The electrode including one or more elements identical to one or more of the elements in the capping layer and includes a material having a Vickers hardness higher than a Vickers hardness of an iron atom.
    Type: Application
    Filed: September 9, 2020
    Publication date: September 16, 2021
    Applicants: Kioxia Corporation, SK hynix Inc.
    Inventors: Taiga ISODA, Eiji KITAGAWA, Young Min EEH, Tadaaki OIKAWA, Kazuya SAWADA, Jin Won JUNG
  • Publication number: 20210083170
    Abstract: According to one embodiment, a magnetic memory device includes a substrate, a first layer stack, and a second layer stack at a same side of the first layer stack relative to the substrate, and farther than the first layer stack from the substrate. Each of the first and second layer stack includes a reference layer, a tunnel barrier layer provided in a direction relative to the reference layer, the direction being perpendicular to the substrate, a storage layer provided in the direction relative to the tunnel barrier layer, and a first nonmagnetic layer provided in the direction relative to the storage layer. A heat absorption rate of the first nonmagnetic layer of the first layer stack is lower than a heat absorption rate of the first nonmagnetic layer of the second layer stack.
    Type: Application
    Filed: March 12, 2020
    Publication date: March 18, 2021
    Applicant: KIOXIA CORPORATION
    Inventors: Kazuya SAWADA, Young Min EEH, Eiji KITAGAWA, Taiga ISODA, Tadaaki OIKAWA, Kenichi YOSHINO
  • Publication number: 20210074908
    Abstract: According to one embodiment, a magnetic device includes a layer stack. The layer stack includes a first ferromagnetic layer, a second ferromagnetic layer, a first nonmagnetic layer between the first ferromagnetic layer and the second ferromagnetic layer, and a second nonmagnetic layer. The first ferromagnetic layer is interposed between the second nonmagnetic layer and the first nonmagnetic layer. The first nonmagnetic layer and the second nonmagnetic layer contain a magnesium oxide (MgO). The first ferromagnetic layer contains a higher amount of boron (B) at an interface with the first nonmagnetic layer than at an interface with the second nonmagnetic layer.
    Type: Application
    Filed: March 12, 2020
    Publication date: March 11, 2021
    Applicant: KIOXIA CORPORATION
    Inventors: Tadaaki OIKAWA, Young Min EEH, Kenichi YOSHINO, Eiji KITAGAWA, Kazuya SAWADA, Taiga ISODA
  • Publication number: 20210074911
    Abstract: According to one embodiment, a magnetoresistive memory device includes: a first ferromagnetic layer; a stoichiometric first layer; a first insulator between the first ferromagnetic layer and the first layer; a second ferromagnetic layer between the first insulator and the first layer; and a non-stoichiometric second layer between the second ferromagnetic layer and the first layer. The second layer is in contact with the second ferromagnetic layer and the first layer.
    Type: Application
    Filed: March 10, 2020
    Publication date: March 11, 2021
    Applicants: KIOXIA CORPORATION, SK HYNIX INC.
    Inventors: Taiga ISODA, Eiji KITAGAWA, Young Min EEH, Tadaaki OIKAWA, Kazuya SAWADA, Kenichi YOSHINO, Jong Koo LIM, Ku Youl JUNG, Guk Cheon KIM
  • Patent number: 10922962
    Abstract: A congestion management apparatus includes a memory configured to store, on a per-action-option basis, upper limits on numbers of users allowed to be guided to action options, and a processor coupled to the memory and configured to: generate the action options by time slot for a user; calculate for each of the generated action options, choice probabilities of the action options with respect to the user, and store the calculated choice probabilities in the memory; and calculate for each of the action options, estimated numbers of previous users assumed to have selected the action options, based on choice probabilities of each of the action options with respect to the previous users, the choice probabilities being obtained from the memory, wherein the processor is configured to extract, based on the upper limits and the estimated numbers for the action options, action options to be presented to the user.
    Type: Grant
    Filed: September 19, 2018
    Date of Patent: February 16, 2021
    Assignee: FUJITSU LIMITED
    Inventors: Takuro Ikeda, Eiji Kitagawa, Vishal Sharma
  • Publication number: 20210014592
    Abstract: A non-transitory computer-readable storage medium storing a program that causes a computer to execute a process, the process includes acquiring first sound data collected by a first microphone and second sound data collected by a second microphone during traveling of a vehicle in which the first microphone is provided in vicinity of a front wheel and the second microphone is provided in vicinity of a rear wheel; and detecting a cavity under a road surface where the vehicle has traveled based on a difference between the acquired first sound data and the acquired second sound data.
    Type: Application
    Filed: June 30, 2020
    Publication date: January 14, 2021
    Applicant: FUJITSU LIMITED
    Inventors: Eiji Kitagawa, Isamu Watanabe, Hitoshi Komoriya
  • Patent number: 10840434
    Abstract: According to an embodiment, a storage device includes a resistance change element. The resistance change element includes a stacked structure including a first ferromagnet, a second ferromagnet, and a first nonmagnet between the first ferromagnet and the second ferromagnet. The first nonmagnet includes a boron-doped rare-earth oxide.
    Type: Grant
    Filed: March 13, 2019
    Date of Patent: November 17, 2020
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Eiji Kitagawa, Young Min Eeh, Tadaaki Oikawa, Kenichi Yoshino, Kazuya Sawada, Taiga Isoda
  • Publication number: 20200302987
    Abstract: According to one embodiment, a magnetic device includes: a first magnetic material provided above a substrate; a second magnetic material provided between the substrate and the first magnetic material; a nonmagnetic material provided between the first magnetic material and the second magnetic material; a first layer provided between the substrate and the second magnetic material and including an amorphous layer; and a second layer provided between the amorphous layer and the second magnetic material and including a crystal layer.
    Type: Application
    Filed: September 10, 2019
    Publication date: September 24, 2020
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Kazuya SAWADA, Young Min EEH, Tadaaki OIKAWA, Kenichi YOSHINO, Eiji KITAGAWA, Taiga ISODA
  • Publication number: 20200294567
    Abstract: According to one embodiment, a magnetoresistive element includes a first magnetic layer having an invariable magnetization direction; a non-magnetic layer provided on the first magnetic layer; a second magnetic layer provided on the non-magnetic layer, having an invariable magnetization direction, and containing a rare-earth element; a third magnetic layer provided on the second magnetic layer and composed of cobalt; and an oxide layer provided on the third magnetic layer.
    Type: Application
    Filed: September 11, 2019
    Publication date: September 17, 2020
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Tadaaki OIKAWA, Young Min EEH, Kazuya SAWADA, Kenichi YOSHINO, Eiji KITAGAWA, Taiga ISODA
  • Publication number: 20200091410
    Abstract: According to an embodiment, a storage device includes a resistance change element. The resistance change element includes a stacked structure including a first ferromagnet, a second ferromagnet, and a first nonmagnet between the first ferromagnet and the second ferromagnet. The first nonmagnet includes a boron-doped rare-earth oxide.
    Type: Application
    Filed: March 13, 2019
    Publication date: March 19, 2020
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Eiji KITAGAWA, Young Min EEH, Tadaaki OIKAWA, Kenichi YOSHINO, Kazuya SAWADA, Taiga ISODA
  • Publication number: 20200082857
    Abstract: According to one embodiment, a magnetic device includes a magnetic tunnel junction element, the magnetic tunnel junction element comprising: a first structure having ferromagnetism; a second structure having ferromagnetism; and a first nonmagnet provided between the first structure and the second structure; wherein: the first structure and the second structure are antiferromagnetically coupled via the first nonmagnet; and the first structure includes a first ferromagnetic nitride.
    Type: Application
    Filed: March 13, 2019
    Publication date: March 12, 2020
    Applicants: TOSHIBA MEMORY CORPORATION, SK HYNIX INC.
    Inventors: Young Min EEH, Taeyoung LEE, Kazuya SAWADA, Eiji KITAGAWA, Taiga ISODA, Tadaaki OIKAWA, Kenichi YOSHINO
  • Publication number: 20200075671
    Abstract: According to one embodiment, a magnetic memory device includes a first magnetic layer having a variable magnetization direction, and including a first main surface and a second main surface located opposite to the first main surface, a second magnetic layer provided on a first main surface side of the first magnetic layer, and having a fixed magnetization direction, and a nonmagnetic layer provided between the first magnetic layer and the second magnetic layer, wherein a saturation magnetization of a part of the first magnetic layer which is located close to the first main surface is higher than a saturation magnetization of a part of the first magnetic layer which is located close to the second main surface.
    Type: Application
    Filed: November 8, 2019
    Publication date: March 5, 2020
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Jyunichi OZEKI, Masahiko NAKAYAMA, Hiroaki YODA, Eiji KITAGAWA, Takao OCHIAI, Minoru AMANO, Kenji NOMA
  • Patent number: 10580969
    Abstract: An electronic device may include a semiconductor memory, and the semiconductor memory may include a first magnetic layer; a second magnetic layer; and a spacer layer interposed between the first magnetic layer and the second magnetic layer, wherein the spacer layer includes a first layer, a second layer and an intermediate layer interposed between the first layer and the second layer, and wherein each of the first layer and the second layer includes an oxide, or a nitride, or a combination of an oxide and a nitride, the intermediate layer includes a multilayer structure including [Ru/x]n or [x/Ru]n, x includes a metal, an oxide, or a nitride, or a combination of a metal, an oxide and a nitride, and n represents an integer of 1 or greater.
    Type: Grant
    Filed: December 4, 2018
    Date of Patent: March 3, 2020
    Assignees: SK hynix Inc., Toshiba Memory Corporation
    Inventors: Tae-Young Lee, Jae-Hyoung Lee, Sung-Woong Chung, Eiji Kitagawa