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: 20240081156
    Abstract: A memory device includes a first ferromagnetic layer; a second ferromagnetic layer; a first insulating layer between the first ferromagnetic layer and the second ferromagnetic layer; a first oxide; a second oxide; and a silicon nitride. The first oxide is over a side surface of the first ferromagnetic layer, a side surface of the first insulating layer, and a side surface of the second ferromagnetic layer. The second oxide is over the first oxide, and includes a magnesium oxide, an aluminum oxide, a silicon oxide, or an alkaline-earth metal oxide. The silicon nitride is over a side surface of the second oxide.
    Type: Application
    Filed: June 15, 2023
    Publication date: March 7, 2024
    Applicant: Kioxia Corporation
    Inventor: Eiji KITAGAWA
  • Publication number: 20240074327
    Abstract: According to one embodiment, a magnetic memory device includes: a first interconnect; a second interconnect; a first switching element provided on the first interconnect; a second switching element provided on the second interconnect; a first insulating layer provided surrounding the first switching element; a second insulating layer surrounding the second switching element and not being in contact with the first insulating layer; a first conductor provided on the first switching element and the first insulating layer; a second conductor provided on the second switching element and the second insulating layer; a first magnetoresistive effect element provided on the first conductor; and a second magnetoresistive effect element provided on the second conductor.
    Type: Application
    Filed: June 12, 2023
    Publication date: February 29, 2024
    Applicant: Kioxia Corporation
    Inventors: Taichi IGARASHI, Yuichi ITO, Eiji KITAGAWA, Masayoshi IWAYAMA
  • Patent number: 11832528
    Abstract: A magnetic memory device includes a substrate; a first magnetoresistive effect element; and a second magnetoresistive effect element provided at a side of the first magnetoresistive effect element opposite to a side of the first magnetoresistive effect element at which the substrate is provided. A heat absorption rate of the first magnetoresistive effect element is lower than a heat absorption rate of the second magnetoresistive effect element.
    Type: Grant
    Filed: April 11, 2022
    Date of Patent: November 28, 2023
    Assignee: Kioxia Corporation
    Inventors: Kazuya Sawada, Young Min Eeh, Eiji Kitagawa, Taiga Isoda, Tadaaki Oikawa, Kenichi Yoshino
  • Publication number: 20230309413
    Abstract: In general, according to one embodiment, a magnetic memory device includes a magnetoresistive effect element. The magnetoresistive effect element includes first to second ferromagnetic layer, a layer stack, and first to third non-magnetic layer. The layer stack is arranged on a side opposite to the first ferromagnetic layer with respect to the second ferromagnetic layer. The third non-magnetic layer is arranged on a side opposite to the second non-magnetic layer with respect to the layer stack and contains a metallic oxide. The layer stack includes a fourth non-magnetic layer being in contact with the third non-magnetic layer and containing platinum (Pt).
    Type: Application
    Filed: September 12, 2022
    Publication date: September 28, 2023
    Applicant: Kioxia Corporation
    Inventors: Eiji KITAGAWA, Young Min EEH
  • Publication number: 20230301205
    Abstract: According to one embodiment, a switching element includes a first electrode, a second electrode, and a switching material layer provided between the first electrode and the second electrode. The switching material layer contains silicon (Si), oxygen (O), arsenic (As), and a predetermined element selected from lead (Pb), silver (Ag), indium (In), tin (Sn), copper (Cu), zinc (Zn), gallium (Ga), germanium (Ge), selenium (Se), antimony (Sb), tellurium (Te), gold (Au) and bismuth (Bi).
    Type: Application
    Filed: September 13, 2022
    Publication date: September 21, 2023
    Applicant: Kioxia Corporation
    Inventors: Taichi IGARASHI, Yuichi ITO, Eiji KITAGAWA
  • Publication number: 20230072970
    Abstract: A magnetoresistance memory device includes first, second, third and fourth ferromagnetic layers; a first and second ferromagnetic oxide layers; a metal layer; an insulating layer. The second ferromagnetic layer includes one of iron and cobalt included in the first ferromagnetic oxide layer and one element of a first element group. The second ferromagnetic oxide layer includes an oxide of an alloy of the one of iron and cobalt included in the second ferromagnetic oxide layer with a first element, which has a standard electrode potential lower than that of iron or cobalt and that of the one element of the first element group included in the second ferromagnetic layer.
    Type: Application
    Filed: December 13, 2021
    Publication date: March 9, 2023
    Applicant: Kioxia Corporation
    Inventors: Taiga ISODA, Eiji KITAGAWA, Young Min EEH, Tadaaki OIKAWA, Kazuya SAWADA
  • Publication number: 20230062011
    Abstract: According to one embodiment, a magnetic memory device includes a first magnetic layer having a variable magnetisation direction, a second magnetic layer having a fixed magnetization direction, a nonmagnetic layer provided between the first magnetic layer and the second magnetic layer, a third magnetic layer provided on a lower side of the first magnetic layer, the second magnetic layer and the nonmagnetic layer, having a fixed magnetization direction antiparallel to the magnetization direction of the second magnetic layer, and formed of an alloy of cobalt (Co) and platinum (Pt), and a buffer layer provided on a lower side of the third magnetic layer and including a first layer portion containing rhenium (Re),
    Type: Application
    Filed: December 9, 2021
    Publication date: March 2, 2023
    Applicant: Kioxia Corporation
    Inventors: Tadaaki OIKAWA, Youngmin EEH, Eiji KITAGAWA, Taiga ISODA
  • Publication number: 20230026414
    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: October 3, 2022
    Publication date: January 26, 2023
    Applicants: KIOXIA CORPORATION, SK HYNIX INC.
    Inventors: Taiga ISODA, Eiji KITAGAWA, Young Min Min EEH, Tadaaki OIKAWA, Kazuya SAWADA, Kenichi YOSHINO, Jong Koo LIM, Ku Youl JUNG, Guk Cheon Cheon KIM
  • Patent number: 11563168
    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: Grant
    Filed: September 9, 2020
    Date of Patent: January 24, 2023
    Assignee: KIOXIA CORPORATION
    Inventors: Kazuya Sawada, Young Min Eeh, Tadaaki Oikawa, Eiji Kitagawa, Taiga Isoda
  • Patent number: 11503393
    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: Grant
    Filed: June 30, 2020
    Date of Patent: November 15, 2022
    Assignee: FUJITSU LIMITED
    Inventors: Eiji Kitagawa, Isamu Watanabe, Hitoshi Komoriya
  • Patent number: 11495740
    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: Grant
    Filed: March 10, 2020
    Date of Patent: November 8, 2022
    Assignees: 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
  • Publication number: 20220302205
    Abstract: According to one embodiment, a magnetic memory device includes a stacked structure including a first magnetic layer having a fixed magnetization direction, a second magnetic layer having a variable magnetization direction, a non-magnetic layer provided between the first magnetic layer and the second magnetic layer, a molybdenum (Mo) layer provided on an opposite side of the non-magnetic layer with respect to the second magnetic layer, and an oxide layer provided between the second magnetic layer and the molybdenum (Mo) layer and containing a predetermined element selected from a rare earth element, silicon (Si) and aluminum (Al).
    Type: Application
    Filed: September 10, 2021
    Publication date: September 22, 2022
    Applicants: Kioxia Corporation, SK hynix Inc.
    Inventors: Tadaaki OIKAWA, Youngmin EEH, Eiji KITAGAWA, Taiga ISODA, Ku Youl JUNG, Jin Won JUNG
  • Publication number: 20220302372
    Abstract: According to one embodiment, a magnetic memory device includes a stacked structure including a first magnetic layer having a variable magnetization direction, a second magnetic layer having a fixed magnetization direction, a non-magnetic layer provided between the first magnetic layer and the second magnetic layer, and an oxide layer provided adjacent to the first magnetic layer, the first magnetic layer being provided between the non-magnetic layer and the oxide layer, and the oxide layer containing a rare earth element, boron (B), and oxygen (O).
    Type: Application
    Filed: September 10, 2021
    Publication date: September 22, 2022
    Applicants: Kioxia Corporation, SK hynix Inc.
    Inventors: Tadaaki OIKAWA, Youngmin EEH, Eiji KITAGAWA, Kazuya SAWADA, Taiga ISODA, Ku Youl JUNG, Jin Won JUNG
  • Patent number: 11449770
    Abstract: An action selection learning device includes a memory; and a processor coupled to the memory and configured to generate a reference model that is a set of model parameter vectors that indicate an influence level of each factor that influences selection of an action alternative, calculate a selection probability for each action alternative, for each of the model parameter vectors, calculate a model parameter vector for each user using a subset of model parameter vectors extracted from the reference model, based on the selection probability for each action alternative and a selection history of the action alternative by each user, generate the action alternatives based on the model parameter vector for each user, and transmit the generated action alternatives to a terminal device.
    Type: Grant
    Filed: September 19, 2019
    Date of Patent: September 20, 2022
    Assignee: FUJITSU LIMITED
    Inventors: Takuro Ikeda, Taizo Anan, Eiji Kitagawa, Vishal Sharma
  • Patent number: 11404098
    Abstract: 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 includes 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: Grant
    Filed: September 9, 2020
    Date of Patent: August 2, 2022
    Assignees: KIOXIA CORPORATION, SK HYNIX INC.
    Inventors: Taiga Isoda, Eiji Kitagawa, Young Min Eeh, Tadaaki Oikawa, Kazuya Sawada, Jin Won Jung
  • Publication number: 20220238792
    Abstract: A magnetic memory device includes a substrate; a first magnetoresistive effect element; and a second magnetoresistive effect element provided at a side of the first magnetoresistive effect element opposite to a side of the first magnetoresistive effect element at which the substrate is provided. A heat absorption rate of the first magnetoresistive effect element is lower than a heat absorption rate of the second magnetoresistive effect element.
    Type: Application
    Filed: April 11, 2022
    Publication date: July 28, 2022
    Applicant: Kioxia Corporation
    Inventors: Kazuya SAWADA, Young Min EEH, Eiji KITAGAWA, Taiga ISODA, Tadaaki OIKAWA, Kenichi YOSHINO
  • Publication number: 20220199136
    Abstract: In general, according to one embodiment, a magnetoresistance memory device includes: a first ferromagnetic layer; an insulating layer above the first ferromagnetic layer; a second ferromagnetic layer above the insulating layer; a third ferromagnetic layer above the second ferromagnetic layer; and a fourth ferromagnetic layer above the third ferromagnetic layer. The third ferromagnetic layer includes an oxide of an alloy including iron. The fourth ferromagnetic layer includes iron and a 5d transition metal.
    Type: Application
    Filed: July 30, 2021
    Publication date: June 23, 2022
    Applicants: Kioxia Corporation, SK hynix Inc.
    Inventors: Taiga ISODA, Young Min EEH, Tadaaki OIKAWA, Eiji KITAGAWA, Kazuya SAWADA, Jin Won JUNG, Jung Hyeok KWAK
  • Patent number: 11335422
    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: Grant
    Filed: September 9, 2020
    Date of Patent: May 17, 2022
    Assignee: KIOXIA CORPORATION
    Inventors: Hisanori Aikawa, Eiji Kitagawa
  • Patent number: 11329215
    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: Grant
    Filed: March 12, 2020
    Date of Patent: May 10, 2022
    Assignee: KIOXIA CORPORATION
    Inventors: Kazuya Sawada, Young Min Eeh, Eiji Kitagawa, Taiga Isoda, Tadaaki Oikawa, Kenichi Yoshino
  • Patent number: 11316095
    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: Grant
    Filed: March 12, 2020
    Date of Patent: April 26, 2022
    Assignee: KIOXIA CORPORATION
    Inventors: Tadaaki Oikawa, Young Min Eeh, Kenichi Yoshino, Eiji Kitagawa, Kazuya Sawada, Taiga Isoda