Patents by Inventor Shinto ICHIKAWA

Shinto ICHIKAWA 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).

  • Patent number: 12035635
    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: February 28, 2023
    Date of Patent: July 9, 2024
    Assignee: TDK CORPORATION
    Inventors: Shinto Ichikawa, Kazuumi Inubushi, Katsuyuki Nakada
  • Patent number: 11967348
    Abstract: This magnetoresistance effect element includes a first ferromagnetic layer, a second ferromagnetic layer, and a nonmagnetic layer provided between the first ferromagnetic layer and the second ferromagnetic layer. At least one of the first ferromagnetic layer and the second ferromagnetic layer has an alloy obtained by adding an additive element to a Heusler alloy. The additive element is any one or more elements selected from the group consisting of H, He, N, O, F, Ne, P, Cl, Ar, Kr, and Xe.
    Type: Grant
    Filed: December 21, 2020
    Date of Patent: April 23, 2024
    Assignee: TDK CORPORATION
    Inventors: Katsuyuki Nakada, Kazuumi Inubushi, Shinto Ichikawa
  • Publication number: 20240112695
    Abstract: A magnetoresistance effect element having a large MR ratio is provided. This magnetoresistance effect element includes: a first ferromagnetic layer; a second ferromagnetic layer; and a nonmagnetic layer. The first ferromagnetic layer includes a first layer and a second layer. The first layer is closer to the nonmagnetic layer than the second layer. The first layer has a Heusler alloy containing at least partially crystallized Co. The second layer contains a material different from the Heusler alloy and has at least a partially crystallized ferromagnetic material. The first layer and the second layer have added first atoms. The first atom is any one selected from the group consisting of Mg, Al, Cr, Mn, Ni, Cu, Zn, Pd, Cd, In, Sn, Sb, Pt, Au, and Bi.
    Type: Application
    Filed: September 27, 2023
    Publication date: April 4, 2024
    Applicant: TDK CORPORATION
    Inventors: Shinto ICHIKAWA, Kazuumi INUBUSHI, Katsuyuki NAKADA
  • Patent number: 11944018
    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: Grant
    Filed: July 6, 2022
    Date of Patent: March 26, 2024
    Assignee: TDK CORPORATION
    Inventors: Kazuumi Inubushi, Katsuyuki Nakada, Shinto Ichikawa
  • Publication number: 20240099152
    Abstract: A magneto resistive element includes a first ferromagnetic layer, a second ferromagnetic layer, a nonmagnetic layer, and a buffer layer. The nonmagnetic layer is between the first ferromagnetic layer and second ferromagnetic layer. The buffer layer is in contact with the first ferromagnetic layer. The first ferromagnetic layer contains a Heusler alloy containing Co. The buffer layer contains at least a first atom, a second atom, and a third atom other than Co as main components. The buffer layer does not contain Co or contains Co at a proportion less than a compositional proportion of the first atom, the second atom, and the third atom. In a case where an atomic radius of any one atom of the first atom, the second atom, and the third atom is taken as a reference, an atomic radius of another atom thereof is 95% or less or 105% or more of the reference.
    Type: Application
    Filed: September 15, 2022
    Publication date: March 21, 2024
    Applicant: TDK CORPORATION
    Inventors: Kazuumi INUBUSHI, Katsuyuki NAKADA, Shinto ICHIKAWA
  • Patent number: 11927649
    Abstract: A magnetoresistance effect element includes a first ferromagnetic layer, a second ferromagnetic layer, a nonmagnetic layer that is disposed between the first ferromagnetic layer and the second ferromagnetic layer, and an insertion layer that is disposed at least one of a position between the first ferromagnetic layer and the nonmagnetic layer and a position between the second ferromagnetic layer and the nonmagnetic layer, in which the nonmagnetic layer is composed of an oxide containing Mg and Ga, and the insertion layer is a ferromagnetic component containing Ga.
    Type: Grant
    Filed: March 8, 2021
    Date of Patent: March 12, 2024
    Assignee: TDK CORPORATION
    Inventors: Shogo Yonemura, Tomoyuki Sasaki, Shinto Ichikawa
  • Publication number: 20230337549
    Abstract: The magnetoresistive effect element includes a first ferromagnetic layer, a second ferromagnetic layer, and a nonmagnetic 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 includes a Heusler alloy layer including a crystal region and an amorphous region.
    Type: Application
    Filed: June 23, 2023
    Publication date: October 19, 2023
    Applicant: TDK CORPORATION
    Inventors: Kazuumi INUBUSHI, Katsuyuki NAKADA, Shinto ICHIKAWA
  • Publication number: 20230292625
    Abstract: This magnetoresistance effect element includes a first ferromagnetic layer, a second ferromagnetic layer, and a nonmagnetic layer provided between the first ferromagnetic layer and the second ferromagnetic layer. At least one of the first ferromagnetic layer and the second ferromagnetic layer has an alloy obtained by adding an additive element to a Heusler alloy. The additive element is any one or more elements selected from the group consisting of H, He, N, O, F, Ne, P, Cl, Ar, Kr, and Xe.
    Type: Application
    Filed: December 21, 2020
    Publication date: September 14, 2023
    Applicant: TDK CORPORATION
    Inventors: Katsuyuki NAKADA, Kazuumi INUBUSHI, Shinto ICHIKAWA
  • Patent number: 11728082
    Abstract: A magnetoresistive effect element includes: a first ferromagnetic layer; a second ferromagnetic layer; and a non-magnetic layer located between the first ferromagnetic layer and the second ferromagnetic layer, wherein a crystal structure of the non-magnetic layer is a spinel structure, wherein the non-magnetic layer contains Mg, Al, X, and O as elements constituting the spinel structure, and wherein the X is at least one or more elements selected from a group consisting of Ti, Pt, and W.
    Type: Grant
    Filed: March 26, 2021
    Date of Patent: August 15, 2023
    Assignee: TDK CORPORATION
    Inventors: Tsuyoshi Suzuki, Shinto Ichikawa, Katsuyuki Nakada
  • Patent number: 11730063
    Abstract: The magnetoresistive effect element includes a first ferromagnetic layer, a second ferromagnetic layer, and a nonmagnetic 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 includes a Heusler alloy layer including a crystal region and an amorphous region.
    Type: Grant
    Filed: December 8, 2020
    Date of Patent: August 15, 2023
    Assignee: TDK CORPORATION
    Inventors: Kazuumi Inubushi, Katsuyuki Nakada, Shinto Ichikawa
  • Patent number: 11696513
    Abstract: This magnetoresistance effect element includes a first ferromagnetic layer, a second ferromagnetic layer, and a tunnel barrier layer which is interposed between the first and second ferromagnetic layers, wherein the tunnel barrier layer has a spinel structure represented by a compositional formula X1-?Y?O?, and the tunnel barrier layer contains one or more additional elements selected from the group consisting of He, Ne, Ar, Kr, Xe, P, C, B, and Si, and in the compositional formula, X represents one or more elements selected from the group consisting of Mg, Zn, Cd, Ag, Pt, and Pb, Y represents one or more elements selected from the group consisting of Al, Ga, and In, a range of ? is 0<??1, and a range of ? is 0.35???1.7.
    Type: Grant
    Filed: February 5, 2021
    Date of Patent: July 4, 2023
    Assignee: TDK CORPORATION
    Inventors: Katsuyuki Nakada, Shinto Ichikawa
  • Publication number: 20230210016
    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: Application
    Filed: February 28, 2023
    Publication date: June 29, 2023
    Applicant: TDK CORPORATION
    Inventors: Shinto ICHIKAWA, Kazuumi INUBUSHI, Katsuyuki NAKADA
  • Publication number: 20230157183
    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: Application
    Filed: January 13, 2023
    Publication date: May 18, 2023
    Applicant: TDK CORPORATION
    Inventors: Shinto ICHIKAWA, Katsuyuki NAKADA
  • 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: 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
  • 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