Patents by Inventor Hiroaki Sukegawa

Hiroaki Sukegawa 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: 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: 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: 11374168
    Abstract: The present invention provides a perpendicularly magnetized film structure exhibiting high interface-induced magnetic anisotropy by utilizing a combination of an alloy comprising Fe as a main component and MgAl2O4 as a basic configuration.
    Type: Grant
    Filed: August 29, 2018
    Date of Patent: June 28, 2022
    Assignee: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Hiroaki Sukegawa, Thomas Scheike, Seiji Mitani
  • Patent number: 11107976
    Abstract: According to an embodiment, a magnetic tunnel junction includes a tunnel barrier layer provided between a first magnetic layer and a second magnetic layer. The tunnel barrier layer is a crystal body made of a stacked structure of a first insulating layer and a second insulating layer. The crystal body is oriented. The first insulating layer is made of an oxide of Mg1-xXx (0?x?0.15). X includes at least one element selected from the group consisting of Al and Ti. The second insulating layer is made of an oxide of an alloy including at least two elements selected from the group consisting of Mg, Al, Zn, and Li. Both the first magnetic layer and the second magnetic layer are made of an alloy including B and at least one element selected from the group consisting of Co and Fe.
    Type: Grant
    Filed: June 8, 2018
    Date of Patent: August 31, 2021
    Assignee: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Hiroaki Sukegawa, Ikhtiar, Shinya Kasai, Kazuhiro Hono, Xiandong Xu
  • Patent number: 11105867
    Abstract: The object of the present invention is to attain an unconventionally high tunnel magnetoresistance (TMR) ratio by using a barrier layer made of an MgAl2O4 type insulator material with a spinel structure. The problem can be solved by a magnetic tunnel junction in which a barrier layer is made of a cubic nonmagnetic material having a spinel structure, and both of two ferromagnetic layers that are adjacently on and below the barrier layer are made of a Co2FeAl Heusler alloy. Preferably, the nonmagnetic material is made of oxide of an Mg1?xAlx (0<x?1) alloy, and exhibits tunnel magnetoresistance of 250% or more and 34000% or less at a room temperature.
    Type: Grant
    Filed: January 31, 2017
    Date of Patent: August 31, 2021
    Assignee: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Hiroaki Sukegawa, Thomas Scheike, Seiji Mitani, Tadakatsu Ohkubo, Kazuhiro Hono, Kouichiro Inomata
  • Publication number: 20210123991
    Abstract: The object of the present invention is to attain an unconventionally high tunnel magnetoresistance (TMR) ratio by using a barrier layer made of an MgAl2O4 type insulator material with a spinel structure. The problem can be solved by a magnetic tunnel junction in which a barrier layer is made of a cubic nonmagnetic material having a spinel structure, and both of two ferromagnetic layers that are adjacently on and below the barrier layer are made of a Co2FeAl Heusler alloy. Preferably, the nonmagnetic material is made of oxide of an Mg1-31 xAlx (0<x?1) alloy, and exhibits tunnel magnetoresistance of 250% or more and 34000% or less at a room temperature.
    Type: Application
    Filed: January 31, 2017
    Publication date: April 29, 2021
    Applicant: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Hiroaki SUKEGAWA, Thomas SCHEIKE, Seiji MITANI, Tadakatsu OHKUBO, Kazuhiro HONO, Kouichiro INOMATA
  • Publication number: 20200357985
    Abstract: The present invention provides a perpendicularly magnetized film structure exhibiting high interface-induced magnetic anisotropy by utilizing a combination of an alloy comprising Fe as a main component and MgAl2O4 as a basic configuration.
    Type: Application
    Filed: August 29, 2018
    Publication date: November 12, 2020
    Applicant: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Hiroaki SUKEGAWA, Thomas SCHEIKE, Seiji MITANI
  • Patent number: 10832719
    Abstract: Disclosed is a perpendicularly magnetized film structure using a highly heat resistant underlayer film on which a cubic or tetragonal perpendicularly magnetized film can grow, comprising a substrate of a cubic single crystal substrate having a (001) plane or a substrate having a cubic oriented film that grows to have the (001) plane; an underlayer formed on the substrate from a thin film of a metal having an hcp structure in which the [0001] direction of the thin metal film forms an angle in the range of 42° to 54° with respect to the <001> direction or the (001) orientation of the substrate; and a perpendicularly magnetized layer located on the metal underlayer and formed from a cubic material selected from a Co-based Heusler alloy and a cobalt-iron (CoFe) alloy having a bcc structure a constituent material, and grown to have the (001) plane.
    Type: Grant
    Filed: December 10, 2018
    Date of Patent: November 10, 2020
    Assignee: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Hiroaki Sukegawa, Zhenchao Wen, Seiji Mitani, Koichiro Inomata, Takao Furubayashi, Jason Paul Hadorn, Tadakatsu Ohkubo, Kazuhiro Hono, Jungwoo Koo
  • Patent number: 10749105
    Abstract: To provide a key monocrystalline magnetoresistance element necessary for accomplishing mass production and cost reduction for applying a monocrystalline giant magnetoresistance element using a Heusler alloy to practical devices. A monocrystalline magnetoresistance element of the present invention includes a silicon substrate 11, a base layer 12 having a B2 structure laminated on the silicon substrate 11, a first non-magnetic layer 13 laminated on the base layer 12 having a B2 structure, and a giant magnetoresistance effect layer 17 having at least one laminate layer including a lower ferromagnetic layer 14, an upper ferromagnetic layer 16, and a second non-magnetic layer 15 disposed between the lower ferromagnetic layer 14 and the upper ferromagnetic layer 16.
    Type: Grant
    Filed: March 29, 2018
    Date of Patent: August 18, 2020
    Assignee: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Jiamin Chen, Yuya Sakuraba, Jun Liu, Hiroaki Sukegawa, Kazuhiro Hono
  • Patent number: 10665776
    Abstract: Provided is a magnetoresistance effect element in which a tunnel barrier layer stably has a cation disordered spinel structure. This magnetoresistance effect element includes a first ferromagnetic layer, a second ferromagnetic layer, and a tunnel barrier layer disposed between the first ferromagnetic layer and the second ferromagnetic layer. In addition, the tunnel barrier layer is an oxide of MgxAl1-x (0?x<1) and an amount of oxygen in the tunnel barrier layer is lower than an amount of oxygen in a fully oxidized state in which the oxide has an ordered spinel structure.
    Type: Grant
    Filed: February 14, 2019
    Date of Patent: May 26, 2020
    Assignees: TDK CORPORATION, NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Shinto Ichikawa, Katsuyuki Nakada, Seiji Mitani, Hiroaki Sukegawa, Kazuhiro Hono, Tadakatsu Ohkubo
  • Publication number: 20200044144
    Abstract: According to an embodiment, a magnetic tunnel junction includes a tunnel barrier layer provided between a first magnetic layer and a second magnetic layer. The tunnel barrier layer is a crystal body made of a stacked structure of a first insulating layer and a second insulating layer. The crystal body is oriented. The first insulating layer is made of an oxide of Mg1-xXx (0?x?0.15). X includes at least one element selected from the group consisting of Al and Ti. The second insulating layer is made of an oxide of an alloy including at least two elements selected from the group consisting of Mg, Al, Zn, and Li. Both the first magnetic layer and the second magnetic layer are made of an alloy including B and at least one element selected from the group consisting of Co and Fe.
    Type: Application
    Filed: June 8, 2018
    Publication date: February 6, 2020
    Applicant: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Hiroaki SUKEGAWA, Ikhtiar ., Shinya KASAI, Kazuhiro HONO, Xiandong XU
  • Patent number: 10395809
    Abstract: Embodiments of the inventive concepts provide a flat perpendicular magnetic layer having a low saturation magnetization and a perpendicular magnetization-type tunnel magnetoresistive element using the same. The perpendicular magnetic layer is a nitrogen-poor (Mn1?xGax)Ny layer (0<x?0.5 and 0<y<0.1) formed by providing nitrogen (N) into a MnGa alloy while adjusting a nitrogen amount. The perpendicular magnetic layer can be formed flat.
    Type: Grant
    Filed: May 10, 2017
    Date of Patent: August 27, 2019
    Assignees: Samsung Electronics Co., Ltd., National Institute for Materials Science
    Inventors: Shigeki Takahashi, Yoshiaki Sonobe, Hiroaki Sukegawa, Hwachol Lee, Kazuhiro Hono, Seiji Mitani, Jun Liu
  • Publication number: 20190259937
    Abstract: Provided is a magnetoresistance effect element in which a tunnel barrier layer stably has a cation disordered spinel structure. This magnetoresistance effect element includes a first ferromagnetic layer, a second ferromagnetic layer, and a tunnel barrier layer disposed between the first ferromagnetic layer and the second ferromagnetic layer. In addition, the tunnel barrier layer is an oxide of MgxAl1-x (0?x<1) and an amount of oxygen in the tunnel barrier layer is lower than an amount of oxygen in a fully oxidized state in which the oxide has an ordered spinel structure.
    Type: Application
    Filed: February 14, 2019
    Publication date: August 22, 2019
    Applicants: TDK CORPORATION, NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Shinto ICHIKAWA, Katsuyuki NAKADA, Seiji MITANI, Hiroaki SUKEGAWA, Kazuhiro HONO, Tadakatsu OHKUBO
  • Publication number: 20190172486
    Abstract: Disclosed is a perpendicularly magnetized film structure using a highly heat resistant underlayer film on which a cubic or tetragonal perpendicularly magnetized film can grow, comprising a substrate of a cubic single crystal substrate having a (001) plane or a substrate having a cubic oriented film that grows to have the (001) plane; an underlayer formed on the substrate from a thin film of a metal having an hcp structure in which the [0001] direction of the thin metal film forms an angle in the range of 42° to 54° with respect to the <001> direction or the (001) orientation of the substrate; and a perpendicularly magnetized layer located on the metal underlayer and formed from a cubic material selected from a Co-based Heusler alloy and a cobalt-iron (CoFe) alloy having a bcc structure a constituent material, and grown to have the (001) plane.
    Type: Application
    Filed: December 10, 2018
    Publication date: June 6, 2019
    Applicant: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Hiroaki SUKEGAWA, Zhenchao WEN, Seiji MITANI, Koichiro INOMATA, Takao FURUBAYASHI, Jason Paul HADORN, Tadakatsu OHKUBO, Kazuhiro HONO, Jungwoo KOO
  • Patent number: 10305027
    Abstract: According to one embodiment, a magnetoresistive element includes a first magnetic layer, a second magnetic layer, and a first nonmagnetic layer. The first nonmagnetic layer is provided between the first magnetic layer and the second magnetic layer. The first nonmagnetic layer includes an oxide including an inverse-spinel structure.
    Type: Grant
    Filed: September 8, 2017
    Date of Patent: May 28, 2019
    Assignees: Kabushiki Kaisha Toshiba, NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Yushi Kato, Tadaomi Daibou, Yuuzo Kamiguchi, Naoharu Shimomura, Junichi Ito, Hiroaki Sukegawa, Mohamed Belmoubarik, Po-Han Cheng, Seiji Mitani, Tadakatsu Ohkubo, Kazuhiro Hono
  • Patent number: 10205091
    Abstract: To provide a key monocrystalline magnetoresistance element necessary for accomplishing mass production and cost reduction for applying a monocrystalline giant magnetoresistance element using a Heusler alloy to practical devices. A monocrystalline magnetoresistance element of the present invention includes a silicon substrate 11, a base layer 12 having a B2 structure laminated on the silicon substrate 11, a first non-magnetic layer 13 laminated on the base layer 12 having a B2 structure, and a giant magnetoresistance effect layer 17 having at least one laminate layer including a lower ferromagnetic layer 14, an upper ferromagnetic layer 16, and a second non-magnetic layer 15 disposed between the lower ferromagnetic layer 14 and the upper ferromagnetic layer 16.
    Type: Grant
    Filed: February 3, 2017
    Date of Patent: February 12, 2019
    Assignee: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Jiamin Chen, Yuya Sakuraba, Jun Liu, Hiroaki Sukegawa, Kazuhiro Hono
  • Patent number: 10199063
    Abstract: Disclosed is a perpendicularly magnetized film structure that uses a highly heat resistant underlayer film on which a cubic or tetragonal perpendicularly magnetized film can grow with high quality, the structure comprising any one substrate (5) of a cubic single crystal substrate having a (001) plane, or a substrate having a cubic oriented film that grows to have the (001) plane; an underlayer (6) formed on the substrate (5) from a thin film of a metal having an hcp structure, such as Ru or Re, in which the [0001] direction of the thin metal film forms an angle in the range of 42° to 54° with respect to the <001> direction or the (001) orientation of the substrate (5); and a perpendicularly magnetized layer (7) located on the metal underlayer (6) and formed from a cubic material selected from the group consisting of a Co-based Heusler alloy, a cobalt-iron (CoFe) alloy having a bcc structure, and the like, as a constituent material, and grown to have the (001) plane.
    Type: Grant
    Filed: March 19, 2015
    Date of Patent: February 5, 2019
    Assignee: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Hiroaki Sukegawa, Zhenchao Wen, Seiji Mitani, Koichiro Inomata, Takao Furubayashi, Jason Paul Hadorn, Tadakatsu Ohkubo, Kazuhiro Hono, Jungwoo Koo
  • Publication number: 20180226573
    Abstract: To provide a key monocrystalline magnetoresistance element necessary for accomplishing mass production and cost reduction for applying a monocrystalline giant magnetoresistance element using a Heusler alloy to practical devices. A monocrystalline magnetoresistance element of the present invention includes a silicon substrate 11, a base layer 12 having a B2 structure laminated on the silicon substrate 11, a first non-magnetic layer 13 laminated on the base layer 12 having a B2 structure, and a giant magnetoresistance effect layer 17 having at least one laminate layer including a lower ferromagnetic layer 14, an upper ferromagnetic layer 16, and a second non-magnetic layer 15 disposed between the lower ferromagnetic layer 14 and the upper ferromagnetic layer 16.
    Type: Application
    Filed: March 29, 2018
    Publication date: August 9, 2018
    Inventors: Jiamin CHEN, Yuya SAKURABA, Jun LIU, Hiroaki SUKEGAWA, Kazuhiro HONO
  • Publication number: 20180090671
    Abstract: According to one embodiment, a magnetoresistive element includes a first magnetic layer, a second magnetic layer, and a first nonmagnetic layer. The first nonmagnetic layer is provided between the first magnetic layer and the second magnetic layer. The first nonmagnetic layer includes an oxide including an inverse-spinel structure.
    Type: Application
    Filed: September 8, 2017
    Publication date: March 29, 2018
    Applicants: Kabushiki Kaisha Toshiba, NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Yushi KATO, Tadaomi DAIBOU, Yuuzo KAMIGUCHI, Naoharu SHIMOMURA, Junichi ITO, Hiroaki SUKEGAWA, Mohamed BELMOUBARIK, Po-Han CHENG, Seiji MITANI, Tadakatsu OHKUBO, Kazuhiro HONO
  • Patent number: 9842636
    Abstract: Provided is a structure having a perpendicular magnetization film which is an (Mn1-xGax)4N1-y (0<x?0.5, 0<y<1) thin film having a nitrogen-deficient composition which is formed by controlling and introducing nitrogen N into an MnGa alloy or a thin film containing at least one of Ge, Zn, Sb, Ni, Ag, Sn, Pt, and Rh, instead of Ga. The perpendicular magnetization film exhibits a Curie temperature sufficiently higher than room temperature, has saturation magnetization smaller than that of existing materials, and is capable of being fabricated as a very flat film.
    Type: Grant
    Filed: April 21, 2016
    Date of Patent: December 12, 2017
    Assignees: NATIONAL INSTITUTE FOR MATERIALS SCIENCE, SAMSUNG ELECTRONICS COMPANY LIMITED
    Inventors: Hiroaki Sukegawa, Hwachol Lee, Kazuhiro Hono, Seiji Mitani, Tadakatsu Ohkubo, Jun Liu, Shinya Kasai, Kwangseok Kim