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).

  • Patent number: 11158785
    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: December 22, 2020
    Date of Patent: October 26, 2021
    Assignee: TDK CORPORATION
    Inventors: Shinto Ichikawa, Kazuumi Inubushi, Katsuyuki Nakada
  • Publication number: 20210328136
    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 represented by a composition formula of AIn2Ox (0?x?4), and an A-site is a non-magnetic divalent cation which is one or more selected from a group consisting of magnesium, zinc and cadmium.
    Type: Application
    Filed: May 28, 2021
    Publication date: October 21, 2021
    Applicant: TDK CORPORATION
    Inventors: Tomoyuki SASAKI, Katsuyuki NAKADA, Tatsuo SHIBATA
  • Publication number: 20210304940
    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: Application
    Filed: March 26, 2021
    Publication date: September 30, 2021
    Applicant: TDK CORPORATION
    Inventors: Tsuyoshi SUZUKI, Shinto ICHIKAWA, Katsuyuki NAKADA
  • Patent number: 11127894
    Abstract: This spin-orbit-torque magnetization rotating element includes a spin-orbit torque wiring extending in a first direction and a first ferromagnetic layer laminated on the spin-orbit torque wiring, wherein the spin-orbit torque wiring includes a compound represented by XYZ or X2YZ with respect to a stoichiometric composition.
    Type: Grant
    Filed: October 30, 2018
    Date of Patent: September 21, 2021
    Assignee: TDK CORPORATION
    Inventors: Katsuyuki Nakada, Yohei Shiokawa
  • Publication number: 20210286028
    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: Application
    Filed: February 2, 2021
    Publication date: September 16, 2021
    Applicant: TDK CORPORATION
    Inventors: Shinto ICHIKAWA, Kazuumi INUBUSHI, Katsuyuki NAKADA
  • Publication number: 20210265562
    Abstract: A magnetoresistive effect element includes a first ferromagnetic layer, a second ferromagnetic layer, a non-magnetic layer disposed between the first ferromagnetic layer and the second ferromagnetic layer, and an additive-containing layer disposed at any position in a laminating direction, at least one of the first ferromagnetic layer and the second ferromagnetic layer is a Heusler alloy containing at least one of boron and carbon, at least part of which is crystallized, and the additive-containing layer is a non-magnetic layer containing at least one of boron and carbon, and any one element selected from the group made of Ti, V, Cr, Cu, Zn, Zr, Mo, Ru, Pd, Ta, W, Ir, Pt and Au.
    Type: Application
    Filed: December 9, 2020
    Publication date: August 26, 2021
    Applicant: TDK CORPORATION
    Inventors: Shinto ICHIKAWA, Kazuumi INUBUSHI, Katsuyuki NAKADA
  • Patent number: 11069852
    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 high-barrier-height layers and one or more low-barrier-height layers, the one or more high-barrier-height layers having a relatively high barrier height with respect to the one or more low-barrier-height layers and the one or more low-barrier-height layers having a relatively low barrier height with respect to the one or more high-barrier-height layers. A minimum difference of barrier height between the one or more high-barrier-height layers and the one or more low-barrier-height layers is equal to or higher than 0.5 eV.
    Type: Grant
    Filed: July 8, 2019
    Date of Patent: July 20, 2021
    Assignee: TDK CORPORATION
    Inventors: Shinto Ichikawa, Katsuyuki Nakada, Tomoyuki Sasaki
  • Patent number: 11056642
    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 represented by a composition formula of AIn2Ox(0<x?4), and an A-site is a non-magnetic divalent cation which is one or more selected from a group consisting of magnesium, zinc and cadmium.
    Type: Grant
    Filed: August 16, 2019
    Date of Patent: July 6, 2021
    Assignee: TDK CORPORATION
    Inventors: Tomoyuki Sasaki, Katsuyuki Nakada, Tatsuo Shibata
  • Patent number: 11056639
    Abstract: A magnetoresistance effect element includes: a first ferromagnetic layer; a second ferromagnetic layer; and a tunnel barrier layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer, wherein the tunnel barrier layer is an oxide having a spinel structure, and the tunnel barrier layer includes a magnetic element as an additional element.
    Type: Grant
    Filed: May 15, 2019
    Date of Patent: July 6, 2021
    Assignee: TDK CORPORATION
    Inventor: Katsuyuki Nakada
  • Publication number: 20210193913
    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: December 22, 2020
    Publication date: June 24, 2021
    Applicant: TDK CORPORATION
    Inventors: Shinto ICHIKAWA, Kazuumi INUBUSHI, Katsuyuki NAKADA
  • Publication number: 20210184103
    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: December 8, 2020
    Publication date: June 17, 2021
    Applicant: TDK CORPORATION
    Inventors: Kazuumi INUBUSHI, Katsuyuki NAKADA, Shinto ICHIKAWA
  • Publication number: 20210165058
    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: Application
    Filed: January 14, 2021
    Publication date: June 3, 2021
    Applicant: TDK CORPORATION
    Inventors: Kazuumi INUBUSHI, Katsuyuki NAKADA
  • Publication number: 20210159396
    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: Application
    Filed: February 5, 2021
    Publication date: May 27, 2021
    Applicant: TDK CORPORATION
    Inventors: Katsuyuki NAKADA, Shinto ICHIKAWA
  • Patent number: 11005035
    Abstract: A magnetoresistive effect element includes a first ferromagnetic layer and a tunnel barrier layer. The tunnel barrier layer has a main body region and a first interface region. The main body region has an oxide material of a first spinel structure represented by a general formula LM2O4. The first interface region has at least one element X selected from a group consisting of elements having a valence of 2 and elements having a valence of 3 excluding Al and has an oxide material of a second spinel structure represented by a general formula DG2O4(D represents one or more kinds of elements including Mg or the element X, and G represents one or more kinds of elements including Al or the element X). A content of the element X contained in the first interface region is larger than that of the element X contained in the main body region.
    Type: Grant
    Filed: March 26, 2019
    Date of Patent: May 11, 2021
    Assignee: TDK CORPORATION
    Inventors: Tsuyoshi Suzuki, Katsuyuki Nakada, Shinto Ichikawa
  • Patent number: 10971679
    Abstract: A magnetoresistive effect element, which includes: a first ferromagnetic layer as a magnetization fixed layer; a second ferromagnetic layer as a magnetization free layer; and a nonmagnetic spacer layer provided between the first ferromagnetic layer and the second ferromagnetic layer. The nonmagnetic spacer layer includes an Ag alloy represented by General Formula (1), and thereby lattice mismatch between the nonmagnetic spacer layer, and the first ferromagnetic layer and/or the second ferromagnetic layer is reduced, compared to lattice mismatch when the nonmagnetic spacer layer is formed of Ag, Ag?X1-???(1) where X indicates one element selected from the group made of Al, Cu, Ga, Ge, As, Y, La, Sm, Yb, and Pt, and 0<?<1.
    Type: Grant
    Filed: December 19, 2019
    Date of Patent: April 6, 2021
    Assignee: TDK CORPORATION
    Inventors: Kazuumi Inubushi, Katsuyuki Nakada
  • Patent number: 10964341
    Abstract: A nonmagnetic spacer layer in a magnetoresistive effect element includes a nonmagnetic metal layer that is formed of Ag and at least one of a first insertion layer that is disposed on a bottom surface of the nonmagnetic metal layer and a second insertion layer that is disposed on a top surface of the nonmagnetic metal layer. The first insertion layer and the second insertion layer include an Fe alloy that is expressed by Fe?X1-?. Here, X denotes one or more elements selected from a group consisting of O, Al, Si, Ga, Mo, Ag, and Au, and ? satisfies 0<y<1.
    Type: Grant
    Filed: August 21, 2020
    Date of Patent: March 30, 2021
    Assignee: TDK CORPORATION
    Inventors: Kazuumi Inubushi, Katsuyuki Nakada
  • Patent number: 10944043
    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: July 2, 2018
    Date of Patent: March 9, 2021
    Assignee: TDK CORPORATION
    Inventors: Katsuyuki Nakada, Shinto Ichikawa
  • Patent number: 10937951
    Abstract: A magnetoresistance effect element according to an aspect of the present disclosure includes a first ferromagnetic layer as a magnetization fixed layer including a ferromagnetic Heusler alloy, a second ferromagnetic layer as a magnetization free layer including a ferromagnetic Heusler alloy, and a nonmagnetic spacer layer provided between the first ferromagnetic layer and the second ferromagnetic layer, and the nonmagnetic spacer layer includes a nonmagnetic Fe group, Co group, or Ni group Heusler alloy.
    Type: Grant
    Filed: March 5, 2018
    Date of Patent: March 2, 2021
    Assignee: TDK CORPORATION
    Inventors: Katsuyuki Nakada, Kazuumi Inubushi
  • Patent number: 10937954
    Abstract: A magnetoresistive effect element includes a first ferromagnetic layer, a second ferromagnetic layer, a nonmagnetic layer, and at least one of a first nonmagnetic insertion layer provided directly on a lower surface of the nonmagnetic layer and a second nonmagnetic insertion layer provided directly on an upper surface of the nonmagnetic layer. The first nonmagnetic insertion layer and the second nonmagnetic insertion layer include an Ag alloy represented by General Formula (1): Ag?X1-? where X indicates one element selected from the group consisting of Al, Cu, Ga, Ge, As, Y, La, Sm, Yb, and Pt, and 0<?<1.
    Type: Grant
    Filed: November 7, 2019
    Date of Patent: March 2, 2021
    Assignee: TDK CORPORATION
    Inventors: Kazuumi Inubushi, Katsuyuki Nakada
  • Patent number: 10937451
    Abstract: A magnetoresistive effect element according to the present invention includes: a first ferromagnetic layer as a magnetization fixed layer; a second ferromagnetic layer as a magnetization free layer; and a nonmagnetic spacer layer provided between the first ferromagnetic layer and the second ferromagnetic layer. The nonmagnetic spacer layer comprises an Al alloy represented by General Formula (1), and thereby lattice mismatch between the nonmagnetic spacer layer and the first ferromagnetic layer and/or the second ferromagnetic layer is reduced, compared to lattice mismatch when the nonmagnetic spacer layer is formed of Al. Al?X1-???(1) [wherein, X indicates one element selected from the group consisting of Li, N, Mg, Si, Sc, Cr, Fe, Ni, Cu, Zn, Ga, Ge, Zr, Ru, Pd, Ag, Sn, W, Pt, Au and Th, and ? is 0.5<?<1.
    Type: Grant
    Filed: March 13, 2020
    Date of Patent: March 2, 2021
    Assignee: TDK CORPORATION
    Inventors: Kazuumi Inubushi, Katsuyuki Nakada