Patents by Inventor Katsuyuki Nakada

Katsuyuki Nakada 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: 20230144429
    Abstract: A magnetoresistance effect element includes a first ferromagnetic layer, a second ferromagnetic layer, and a nonmagnetic layer. The nonmagnetic layer is between the first ferromagnetic layer and the second ferromagnetic layer. At least one of the first ferromagnetic layer and the second ferromagnetic layer is a Heusler alloy layer. The nonmagnetic layer includes a first region and a second region in a plane. Both of the first region and the second region are formed of a metal. The second region is different in constituent material from the first region. The second region has a crystal structure of a body-centered cubic lattice structure (bcc).
    Type: Application
    Filed: November 4, 2022
    Publication date: May 11, 2023
    Applicant: TDK CORPORATION
    Inventors: Shinto ICHIKAWA, Katsuyuki NAKADA, Kazuumi INUBUSHI
  • Patent number: 11621392
    Abstract: A magnetoresistance effect element includes: a first ferromagnetic layer; a second ferromagnetic layer; and a non-magnetic layer provided between the first ferromagnetic layer and the second ferromagnetic layer, wherein at least one of the first ferromagnetic layer and the second ferromagnetic layer includes a first layer and a second layer in order from the side closer to the non-magnetic layer, the first layer contains a crystallized Co-based Heusler alloy, at least a part of the second layer is crystallized, the second layer contains a ferromagnetic element, boron element and an additive element, and the additive element is any element selected from a group consisting of Ti, V, Cr, Cu, Zn, Zr, Mo, Ru, Pd, Ta, W, Ir, Pt, and Au.
    Type: Grant
    Filed: September 21, 2021
    Date of Patent: April 4, 2023
    Assignee: TDK CORPORATION
    Inventors: Shinto Ichikawa, Kazuumi Inubushi, Katsuyuki Nakada
  • Patent number: 11600771
    Abstract: A magnetoresistance effect element has an underlayer, a first ferromagnetic metal layer, a second ferromagnetic metal layer, and a tunnel barrier layer that is sandwiched between the first and second ferromagnetic metal layers. The tunnel barrier layer has a spinel structure and includes at least one lattice-matched portion, and at least one lattice-mismatched portion. The underlayer is made of a nitride layer; a layer having a (001)-oriented tetragonal or cubic structure; or a layer having a stacked structure with a combination of a nitride layer having a (001)-oriented NaCl structure and a layer having a (001)-oriented tetragonal or cubic structure.
    Type: Grant
    Filed: May 28, 2021
    Date of Patent: March 7, 2023
    Assignee: TDK CORPORATION
    Inventors: Tomoyuki Sasaki, Katsuyuki Nakada, Tatsuo Shibata
  • Patent number: 11594674
    Abstract: A tunnel barrier layer includes a non-magnetic oxide, wherein a crystal structure of the tunnel barrier layer includes both an ordered spinel structure and a disordered spinel structure.
    Type: Grant
    Filed: March 18, 2020
    Date of Patent: February 28, 2023
    Assignee: TDK CORPORATION
    Inventors: Shinto Ichikawa, Katsuyuki Nakada
  • Patent number: 11585873
    Abstract: A magnetoresistive effect element includes: a first ferromagnetic layer; a second ferromagnetic layer; and a non-magnetic layer provided between the first ferromagnetic layer and the second ferromagnetic layer, wherein the non-magnetic layer includes a first layer and a second layer, and wherein a lattice constant ? of the first layer and a lattice constant ? of the second layer satisfy a relationship of ??0.04×??2×???+0.04×?.
    Type: Grant
    Filed: July 8, 2021
    Date of Patent: February 21, 2023
    Assignees: TDK CORPORATION, NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Shinto Ichikawa, Katsuyuki Nakada, Hiroaki Sukegawa, Seiji Mitani, Tadakatsu Ohkubo, Kazuhiro Hono
  • Patent number: 11581365
    Abstract: Provided are magnetoresistance effect element and a Heusler alloy in which an amount of energy required to rotate magnetization can be reduced. The magnetoresistance effect element includes a first ferromagnetic layer, a second ferromagnetic layer, and a non-magnetic layer positioned between the first ferromagnetic layer and the second ferromagnetic layer, in which at least one of the first ferromagnetic layer and the second ferromagnetic layer is a Heusler alloy in which a portion of elements of an alloy represented by Co2Fe?Z? is substituted with a substitution element, in which Z is one or more elements selected from the group consisting of Mn, Cr, Al, Si, Ga, Ge, and Sn, ? and ? satisfy 2.3??+?, ?<?, and 0.5<?<1.9, and the substitution element is an element different from the Z element and has a smaller magnetic moment than Co.
    Type: Grant
    Filed: August 6, 2020
    Date of Patent: February 14, 2023
    Assignee: TDK CORPORATION
    Inventors: Katsuyuki Nakada, Kazuumi Inubushi
  • Publication number: 20230025589
    Abstract: A magnetoresistance effect element of the present disclosure includes a first Ru alloy layer, a first ferromagnetic layer, a non-magnetic metal layer, and a second ferromagnetic layer in order, wherein the first Ru alloy layer contains one or more Ru alloys represented by the following general formula (1), Ru?X1-???(1) where, in the general formula (1), the symbol X represents one or more elements selected from the group consisting of Be, B, Ti, Y, Zr, Nb, Mo, Rh, In, Sn, La, Ce, Nd, Sm, Gd, Dy, Er, Ta, W, Re, Os, and Ir, and the symbol ? represents a number satisfying 0.5<?<1, the first ferromagnetic layer contains a Heusler alloy, and the second ferromagnetic layer contains a Heusler alloy.
    Type: Application
    Filed: July 6, 2022
    Publication date: January 26, 2023
    Applicant: TDK CORPORATION
    Inventors: Kazuumi INUBUSHI, Katsuyuki NAKADA, Shinto ICHIKAWA
  • Publication number: 20230009284
    Abstract: A magnetoresistive effect element includes: a first ferromagnetic layer; a second ferromagnetic layer; and a non-magnetic layer provided between the first ferromagnetic layer and the second ferromagnetic layer, wherein the non-magnetic layer includes a first layer and a second layer, and wherein a lattice constant ? of the first layer and a lattice constant ? of the second layer satisfy a relationship of ??0.04×??2×???+0.04 ×?.
    Type: Application
    Filed: July 8, 2021
    Publication date: January 12, 2023
    Applicants: TDK CORPORATION, NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Shinto ICHIKAWA, Katsuyuki NAKADA, Hiroaki SUKEGAWA, Seiji MITANI, Tadakatsu OHKUBO, Kazuhiro HONO
  • Patent number: 11525873
    Abstract: A magnetoresistance effect element includes a first ferromagnetic layer, a second ferromagnetic layer, a first non-magnetic layer; and a second non-magnetic layer, wherein, the first ferromagnetic layer and the second ferromagnetic layer are formed so that at least one of them includes a Heusler alloy layer, the first non-magnetic layer is provided between the first ferromagnetic layer and the second ferromagnetic layer, the second non-magnetic layer is in contact with any surface of the Heusler alloy layer and has a discontinuous portion with respect to a lamination surface, and the second non-magnetic layer is made of a material different from that of the first non-magnetic layer and is a (001)-oriented oxide containing Mg.
    Type: Grant
    Filed: February 2, 2021
    Date of Patent: December 13, 2022
    Assignee: TDK CORPORATION
    Inventors: Shinto Ichikawa, Kazuumi Inubushi, Katsuyuki Nakada
  • Publication number: 20220328067
    Abstract: A magnetoresistance effect element includes a first ferromagnetic layer, a second ferromagnetic layer, and a non-magnetic layer positioned between the first ferromagnetic layer and the second ferromagnetic layer, and at least one of the first ferromagnetic layer and the second ferromagnetic layer is a Heusler alloy represented by the following General Formula (1): Co2Fe?X???(1) (in Formula (1), X represents one or more elements selected from the group consisting of Mn, Cr, Si, Al, Ga and Ge, and ? and ? represent numbers that satisfy 2.3??+?, ?<?, and 0.5<?<1.9).
    Type: Application
    Filed: June 29, 2022
    Publication date: October 13, 2022
    Applicant: TDK CORPORATION
    Inventors: Kazuumi INUBUSHI, Katsuyuki NAKADA, Tetsuya UEMURA
  • Patent number: 11450342
    Abstract: A magnetoresistance effect element includes a underlayer, a protective layer, a laminated body located between the underlayer and the protective layer and including a first ferromagnetic layer, a non-magnetic layer, and a second ferromagnetic layer in order from a side closest to the underlayer, and an intermediate layer located between the underlayer and the first ferromagnetic layer, or between the second ferromagnetic layer and the protective layer, wherein, one ferromagnetic layer selected from the first ferromagnetic layer and the second ferromagnetic layer and in contact with the intermediate layer is a Heusler alloy having a Co basis, and a main component of the intermediate layer is an element other than Co among elements constituting the Heusler alloy having the Co basis.
    Type: Grant
    Filed: June 23, 2021
    Date of Patent: September 20, 2022
    Assignee: TDK CORPORATION
    Inventors: Kazuumi Inubushi, Katsuyuki Nakada
  • Publication number: 20220278272
    Abstract: A magnetoresistance effect element includes a first ferromagnetic layer, a second ferromagnetic layer, and a tunnel barrier layer that is interposed between the first ferromagnetic layer and the second ferromagnetic layer. The tunnel barrier layer is a stacked body including one or more first oxide layers having a spinel structure and one or more second oxide layers having a spinel structure with a composition which is different from a composition of the first oxide layer.
    Type: Application
    Filed: May 17, 2022
    Publication date: September 1, 2022
    Applicant: TDK CORPORATION
    Inventors: Shinto ICHIKAWA, Katsuyuki NAKADA, Tomoyuki SASAKI
  • Publication number: 20220278271
    Abstract: In the magnetoresistance effect element according to one aspect, the metal oxide constituting the metal oxide layer has the ratio of oxygen higher than the total ratio of metal when the composition is expressed in the stoichiometric composition; and the resistivity of the metal oxide layer is higher than that of the tunnel barrier layer.
    Type: Application
    Filed: June 24, 2020
    Publication date: September 1, 2022
    Applicant: TDK CORPORATION
    Inventors: Shinto ICHIKAWA, Tsuyoshi SUZUKI, Katsuyuki NAKADA, Tomoyuki SASAKI
  • Patent number: 11422211
    Abstract: A stacked structure is positioned on a nonmagnetic metal layer. The stacked structure includes a ferromagnetic layer and an intermediate layer interposed between the nonmagnetic metal layer and the ferromagnetic layer. The intermediate layer includes a NiAlX alloy layer represented by Formula (1): Ni?1Al?2X?3 . . . (1), [X indicates one or more elements selected from the group consisting of Si, Sc, Ti, Cr, Mn, Fe, Co, Cu, Zr, Nb, and Ta, and satisfies an expression of 0<?<0.5 in a case of ?=?3/(?1+?2+?3)].
    Type: Grant
    Filed: January 14, 2021
    Date of Patent: August 23, 2022
    Assignee: TDK CORPORATION
    Inventors: Kazuumi Inubushi, Katsuyuki Nakada
  • Patent number: 11410689
    Abstract: A magnetoresistance effect element includes a first ferromagnetic layer, a second ferromagnetic layer, and a non-magnetic layer positioned between the first ferromagnetic layer and the second ferromagnetic layer, and at least one of the first ferromagnetic layer and the second ferromagnetic layer is a Heusler alloy represented by the following General Formula (1): Co2Fe?X???(1) (in Formula (1), X represents one or more elements selected from the group consisting of Mn, Cr, Si, Al, Ga and Ge, and ? and ? represent numbers that satisfy 2.3??+?, ?<?, and 0.5<?<1.9).
    Type: Grant
    Filed: August 4, 2020
    Date of Patent: August 9, 2022
    Assignee: TDK CORPORATION
    Inventors: Kazuumi Inubushi, Katsuyuki Nakada, Tetsuya Uemura
  • Publication number: 20220238136
    Abstract: A magnetoresistance effect element and a Heusler alloy in which a state change due to annealing does not easily occur. The element includes a first ferromagnetic layer, a second ferromagnetic layer, and a non-magnetic layer positioned between the first ferromagnetic layer and the second ferromagnetic layer, in which at least one of the first ferromagnetic layer and the second ferromagnetic layer is a Heusler alloy in which a portion of elements of an alloy represented by Co2Fe?Z? is substituted with a substitution element, in which Z is one or more elements selected from the group consisting of Al, Si, Ga, Ge, and Sn, ? and ? satisfy 2.3??+?, ?<?, and 0.5<?<1.9, and the substitution element is one or more elements selected from the group consisting of elements having a melting point higher than that of Fe among elements of Groups 4 to 10.
    Type: Application
    Filed: April 6, 2022
    Publication date: July 28, 2022
    Applicant: TDK CORPORATION
    Inventors: Kazuumi INUBUSHI, Katsuyuki NAKADA
  • Patent number: 11367834
    Abstract: A magnetoresistance effect element has a first ferromagnetic metal layer, a second ferromagnetic metal layer, and a tunnel barrier layer that is sandwiched between the first and second ferromagnetic metal layers, and the tunnel barrier layer has a spinel structure in which cations are disordered, and contains a divalent cation of a non-magnetic element, a trivalent cation of a non-magnetic element, oxygen, and one of nitrogen and fluorine.
    Type: Grant
    Filed: August 24, 2020
    Date of Patent: June 21, 2022
    Assignee: TDK CORPORATION
    Inventors: Tomoyuki Sasaki, Tatsuo Shibata, Katsuyuki Nakada, Yoshitomo Tanaka
  • Patent number: 11362270
    Abstract: A magnetoresistance effect element includes a first ferromagnetic layer, a second ferromagnetic layer, and a tunnel barrier layer that is interposed between the first ferromagnetic layer and the second ferromagnetic layer. The tunnel barrier layer is a stacked body including one or more first oxide layers having a spinel structure and one or more second oxide layers having a spinel structure with a composition which is different from a composition of the first oxide layer.
    Type: Grant
    Filed: October 1, 2020
    Date of Patent: June 14, 2022
    Assignee: TDK CORPORATION
    Inventors: Shinto Ichikawa, Katsuyuki Nakada, Tomoyuki Sasaki
  • Patent number: 11335365
    Abstract: A magnetoresistance effect element and a Heusler alloy in which a state change due to annealing does not easily occur. The element includes a first ferromagnetic layer, a second ferromagnetic layer, and a non-magnetic layer positioned between the first ferromagnetic layer and the second ferromagnetic layer, in which at least one of the first ferromagnetic layer and the second ferromagnetic layer is a Heusler alloy in which a portion of elements of an alloy represented by Co2Fe?Z? is substituted with a substitution element, in which Z is one or more elements selected from the group consisting of Al, Si, Ga, Ge, and Sn, ? and ? satisfy 2.3??+?, ?<?, and 0.5<?<1.9, and the substitution element is one or more elements selected from the group consisting of elements having a melting point higher than that of Fe among elements of Groups 4 to 10.
    Type: Grant
    Filed: August 4, 2020
    Date of Patent: May 17, 2022
    Assignee: TDK CORPORATION
    Inventors: Kazuumi Inubushi, Katsuyuki Nakada
  • Patent number: 11309115
    Abstract: A magnetoresistance effect element includes a first ferromagnetic layer, a second ferromagnetic layer, and a nonmagnetic spacer layer between the first ferromagnetic layer and the second ferromagnetic layer, in which at least one of the first ferromagnetic layer and the second ferromagnetic layer contains a metal compound having a half-Heusler type crystal structure, the metal compound contains a functional material, and X atoms, Y atoms, and Z atoms which form a unit lattice of the half-Heusler type crystal structure, and the functional material has an atomic number lower than an atomic number of any of the X atoms, the Y atoms, and the Z atoms.
    Type: Grant
    Filed: January 30, 2020
    Date of Patent: April 19, 2022
    Assignee: TDK CORPORATION
    Inventor: Katsuyuki Nakada