Patents by Inventor Fumihito Koike

Fumihito Koike 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: 11693068
    Abstract: An exchange-coupled film includes a antiferromagnetic layer and a pinned magnetic layer including a ferromagnetic layer stacked together, the antiferromagnetic layer having a structure including an IrMn layer, a first PtMn layer, a PtCr layer, and a second PtMn layer stacked in that order, the IrMn layer being in contact with the pinned magnetic layer. The second PtMn layer preferably has a thickness of more than 0 ? and less than 60 ?, in some cases. The PtCr layer preferably has a thickness of 100 ? or more, in some cases. The antiferromagnetic layer preferably has a total thickness of 200 ? or less, in some cases.
    Type: Grant
    Filed: June 24, 2021
    Date of Patent: July 4, 2023
    Assignee: ALPS ALPINE CO., LTD.
    Inventors: Masamichi Saito, Fumihito Koike
  • Patent number: 11578996
    Abstract: A position detection element includes an exchange coupling film having a large exchange coupling magnetic field and a position detection apparatus showing good detection accuracy in a high temperature environment. The position detection element includes an exchange coupling film composed of a fixed magnetic layer and an antiferromagnetic layer stacked on the fixed magnetic layer. The antiferromagnetic layer includes an X(Cr—Mn) layer containing X that is one or more elements selected from the group consisting of platinum group metals and Ni and containing Mn and Cr. The X(Cr—Mn) layer includes a PtMn layer as a first region relatively closer to the fixed magnetic layer and a PtCr layer as a second region relatively farther from the fixed magnetic layer. The content of Mn in the first region is higher than the content of Mn in the second region.
    Type: Grant
    Filed: June 23, 2020
    Date of Patent: February 14, 2023
    Assignee: ALPS ALPINE CO., LTD.
    Inventors: Masamichi Saito, Fumihito Koike
  • Patent number: 11488758
    Abstract: In an exchange coupling film that has a large magnetic field (Hex) in which the direction of magnetization of a fixed magnetic layer is reversed, high stability under high temperature conditions, and excellent strong-magnetic field resistance, an antiferromagnetic layer, a fixed magnetic layer, and a free magnetic layer are stacked, the antiferromagnetic layer is composed of a PtCr layer and an XMn layer (where X is Pt or Ir), the XMn layer is in contact with the fixed magnetic layer, and the fixed magnetic layer is made of iron, cobalt, an iron-cobalt alloy, or an iron-nickel alloy.
    Type: Grant
    Filed: March 12, 2020
    Date of Patent: November 1, 2022
    Assignee: ALPS ALPINE CO., LTD.
    Inventors: Masamichi Saito, Fumihito Koike, Hiroaki Endo
  • Patent number: 11476413
    Abstract: A tunnel magnetoresistance effect (TMR) device includes an exchange coupling film having a first ferromagnetic layer, which is at least a portion of a fixed magnetic layer, and an antiferromagnetic layer laminated on the first ferromagnetic layer. The ferromagnetic layer includes an X(Cr—Mn) layer containing one or two or more elements X selected from the group consisting of the platinum group elements and Ni, and also containing Mn and Cr. The X(Cr—Mn) layer has a first region relatively near the first ferromagnetic layer, and a second region relatively far away from the first ferromagnetic layer, and the content of Mn in the first region is higher than that in the second region.
    Type: Grant
    Filed: June 23, 2020
    Date of Patent: October 18, 2022
    Assignee: ALPS ALPINE CO., LTD.
    Inventors: Masamichi Saito, Fumihito Koike
  • Patent number: 11476414
    Abstract: An exchange coupling film in which a magnetic field (Hex) at which the magnetization direction of a pinned magnetic layer is reversed is high, in which stability under high-temperature conditions is high, and which is excellent in strong-magnetic field resistance. The exchange coupling film includes an antiferromagnetic layer and a pinned magnetic layer including a ferromagnetic layer, the antiferromagnetic layer and the pinned magnetic layer being stacked together. The antiferromagnetic layer has a structure including a PtCr layer, a PtMn layer, and an IrMn layer stacked in this order. The IrMn layer is in contact with the pinned magnetic layer. The thickness of the PtMn layer is 12 ? or more, and the thickness of the IrMn layer is 6 ?. The sum of the thickness of the PtMn layer and the thickness of the IrMn layer is 20 ? or more.
    Type: Grant
    Filed: January 21, 2020
    Date of Patent: October 18, 2022
    Assignee: ALPS ALPINE CO., LTD.
    Inventors: Masamichi Saito, Hiroaki Endo, Fumihito Koike
  • Patent number: 11428757
    Abstract: An exchange-coupling film having a large magnetic field (Hex) at which the magnetization direction of a pinned magnetic layer is reversed, thus exhibiting high stability under high-temperature conditions, and having excellent high-magnetic-field resistance includes an antiferromagnetic layer and a pinned magnetic layer in contact with the antiferromagnetic layer. The antiferromagnetic layer has an alternating multilayer structure of three or more layers, the layers including alternately stacked X1Cr and X2Mn layers, where X1 represents one or more elements selected from the group consisting of platinum group elements and Ni, and X2 represents one or more elements selected from the group consisting of platinum group elements and Ni and may be the same as or different from X1.
    Type: Grant
    Filed: March 12, 2020
    Date of Patent: August 30, 2022
    Assignee: ALPS ALPINE CO., LTD.
    Inventors: Masamichi Saito, Hiroaki Endo, Fumihito Koike
  • Publication number: 20210382122
    Abstract: An exchange-coupled film includes a antiferromagnetic layer and a pinned magnetic layer including a ferromagnetic layer stacked together, the antiferromagnetic layer having a structure including an IrMn layer, a first PtMn layer, a PtCr layer, and a second PtMn layer stacked in that order, the IrMn layer being in contact with the pinned magnetic layer. The second PtMn layer preferably has a thickness of more than 0 ? and less than 60 ?, in some cases. The PtCr layer preferably has a thickness of 100 ? or more, in some cases. The antiferromagnetic layer preferably has a total thickness of 200 ? or less, in some cases.
    Type: Application
    Filed: June 24, 2021
    Publication date: December 9, 2021
    Inventors: Masamichi Saito, Fumihito Koike
  • Publication number: 20200328344
    Abstract: A tunnel magnetoresistance effect (TMR) device includes an exchange coupling film having a first ferromagnetic layer, which is at least a portion of a fixed magnetic layer, and an antiferromagnetic layer laminated on the first ferromagnetic layer. The ferromagnetic layer includes an X(Cr—Mn) layer containing one or two or more elements X selected from the group consisting of the platinum group elements and Ni, and also containing Mn and Cr. The X(Cr—Mn) layer has a first region relatively near the first ferromagnetic layer, and a second region relatively far away from the first ferromagnetic layer, and the content of Mn in the first region is higher than that in the second region.
    Type: Application
    Filed: June 23, 2020
    Publication date: October 15, 2020
    Inventors: Masamichi Saito, Fumihito Koike
  • Publication number: 20200318996
    Abstract: A position detection element includes an exchange coupling film having a large exchange coupling magnetic field and a position detection apparatus showing good detection accuracy in a high temperature environment. The position detection element includes an exchange coupling film composed of a fixed magnetic layer and an antiferromagnetic layer stacked on the fixed magnetic layer. The antiferromagnetic layer includes an X(Cr—Mn) layer containing X that is one or more elements selected from the group consisting of platinum group metals and Ni and containing Mn and Cr. The X(Cr—Mn) layer includes a PtMn layer as a first region relatively closer to the fixed magnetic layer and a PtCr layer as a second region relatively farther from the fixed magnetic layer. The content of Mn in the first region is higher than the content of Mn in the second region.
    Type: Application
    Filed: June 23, 2020
    Publication date: October 8, 2020
    Inventors: Masamichi Saito, Fumihito Koike
  • Publication number: 20200284857
    Abstract: An exchange-coupling film having a large magnetic field (Hex) at which the magnetization direction of a pinned magnetic layer is reversed, thus exhibiting high stability under high-temperature conditions, and having excellent high-magnetic-field resistance includes an antiferromagnetic layer and a pinned magnetic layer in contact with the antiferromagnetic layer. The antiferromagnetic layer has an alternating multilayer structure of three or more layers, the layers including alternately stacked X1Cr and X2Mn layers, where X1 represents one or more elements selected from the group consisting of platinum group elements and Ni, and X2 represents one or more elements selected from the group consisting of platinum group elements and Ni and may be the same as or different from X1.
    Type: Application
    Filed: March 12, 2020
    Publication date: September 10, 2020
    Inventors: Masamichi Saito, Hiroaki Endo, Fumihito Koike
  • Publication number: 20200211746
    Abstract: In an exchange coupling film that has a large magnetic field (Hex) in which the direction of magnetization of a fixed magnetic layer is reversed, high stability under high temperature conditions, and excellent strong-magnetic field resistance, an antiferromagnetic layer, a fixed magnetic layer, and a free magnetic layer are stacked, the antiferromagnetic layer is composed of a PtCr layer and an XMn layer (where X is Pt or Ir), the XMn layer is in contact with the fixed magnetic layer, and the fixed magnetic layer is made of iron, cobalt, an iron-cobalt alloy, or an iron-nickel alloy.
    Type: Application
    Filed: March 12, 2020
    Publication date: July 2, 2020
    Inventors: Masamichi Saito, Fumihito Koike, Hiroaki Endo
  • Publication number: 20200161538
    Abstract: An exchange coupling film in which a magnetic field (Hex) at which the magnetization direction of a pinned magnetic layer is reversed is high, in which stability under high-temperature conditions is high, and which is excellent in strong-magnetic field resistance. The exchange coupling film includes an antiferromagnetic layer and a pinned magnetic layer including a ferromagnetic layer, the antiferromagnetic layer and the pinned magnetic layer being stacked together. The antiferromagnetic layer has a structure including a PtCr layer, a PtMn layer, and an IrMn layer stacked in this order. The IrMn layer is in contact with the pinned magnetic layer. The thickness of the PtMn layer is 12 ? or more, and the thickness of the IrMn layer is 6 ?. The sum of the thickness of the PtMn layer and the thickness of the IrMn layer is 20 ? or more.
    Type: Application
    Filed: January 21, 2020
    Publication date: May 21, 2020
    Inventors: Masamichi Saito, Hiroaki Endo, Fumihito Koike
  • Patent number: 10650849
    Abstract: An exchange-coupled film according to the present invention includes an antiferromagnetic layer, pinned magnetic layer, and free magnetic layer which are stacked. The antiferromagnetic layer is composed of a Pt—Cr sublayer and an X—Mn sublayer (where X is Pt or Ir). The X—Mn sublayer is in contact with the pinned magnetic layer. The Pt—Cr sublayer has a composition represented by the formula Pt?Cr100 at %-? (? is 44 at % to 58 at %) when the X—Mn sublayer is placed on the Pt—Cr sublayer or has a composition represented by the formula Pt?Cr100 at %-? (? is 44 at % to 57 at %) when the X—Mn sublayer is placed on the pinned magnetic layer.
    Type: Grant
    Filed: February 11, 2019
    Date of Patent: May 12, 2020
    Assignee: ALPS ALPINE CO., LTD.
    Inventors: Masamichi Saito, Fumihito Koike, Hiroaki Endo
  • Publication number: 20190189150
    Abstract: An exchange-coupled film according to the present invention includes an antiferromagnetic layer, pinned magnetic layer, and free magnetic layer which are stacked. The antiferromagnetic layer is composed of a Pt—Cr sublayer and an X-Mn sublayer (where X is Pt or Ir). The X-Mn sublayer is in contact with the pinned magnetic layer. The Pt—Cr sublayer has a composition represented by the formula Pt?Cr100at %-? (? is 44 at % to 58 at %) when the X—Mn sublayer is placed on the Pt—Cr sublayer or has a composition represented by the formula Pt?Cr100 at %-? (? is 44 at % to 57 at %) when the X—Mn sublayer is placed on the pinned magnetic layer.
    Type: Application
    Filed: February 11, 2019
    Publication date: June 20, 2019
    Inventors: Masamichi SAITO, Fumihito KOIKE, Hiroaki ENDO
  • Publication number: 20190170835
    Abstract: An exchange-coupled film includes an antiferromagnetic layer, pinned magnetic layer, and free magnetic layer which are stacked. The antiferromagnetic layer is composed of a Pt—Cr sublayer and an X—Mn sublayer (where X is Pt or Ir). The X—Mn sublayer is in contact with the pinned magnetic layer.
    Type: Application
    Filed: February 11, 2019
    Publication date: June 6, 2019
    Inventors: Hiroaki ENDO, Fumihito KOIKE, Masamichi SAITO
  • Patent number: 9915710
    Abstract: A magnetic sensor is provided in which in a case where magnetization amounts of the first ferromagnetic layer and the second ferromagnetic layer in the first magnetic sensor element are respectively set to be Mst11 and Mst12 and magnetization amounts of the first ferromagnetic layer and the second ferromagnetic layer in the second magnetic sensor element are respectively set to be Mst21 and Mst22, in a case of Mst11>Mst12, a relationship of Mst21>Mst22 is satisfied, and in a case of Mst11<Mst12, a relationship of Mst21<Mst22 is satisfied.
    Type: Grant
    Filed: April 1, 2016
    Date of Patent: March 13, 2018
    Assignee: ALPS ELECTRIC CO., LTD.
    Inventors: Fumihito Koike, Hirofumi Okumura, Eiji Shinohara, Kazuhiro Shigeta, Taku Saito
  • Patent number: 9530957
    Abstract: A magnetic sensor includes magnetoresistive elements and a soft magnetic body. The magnetoresistive elements have multi layers including a magnetic layer and a nonmagnetic layer on a substrate, and exert a magnetoresistance effect. The soft magnetic body is electrically disconnected with the magnetoresistive elements, and converts a vertical magnetic field component from the outside into a magnetic field component in a horizontal direction so as to provide the magnetoresistive elements with the horizontally converted magnetic field component. The magnetoresistive elements have a pinned magnetic layer having a fixed magnetization direction and a free magnetic layer having a variable magnetization direction. The free magnetic layer is stacked on the pinned magnetic layer with a nonmagnetic layer interposed between the free magnetic layer and the pinned magnetic layer. The magnetization directions of the pinned magnetic layers of the magnetoresistive elements are the same direction.
    Type: Grant
    Filed: April 13, 2012
    Date of Patent: December 27, 2016
    Assignee: ALPS ELECTRIC CO., LTD.
    Inventors: Shinji Sugihara, Fumihito Koike, Yasushi Watanabe, Hideto Ando
  • Publication number: 20160341802
    Abstract: A magnetic sensor includes: a first magnetic detection element group and a second magnetic detection element group each of which including a plurality of self-pinned magnetoresistive effect elements; and a first control unit and a second control unit configured to respectively process detection signals detected from a magnetic field by the magnetoresistive effect elements of the first magnetic detection element group and the second magnetic detection element group, in which pinned magnetization directions of at least two magnetoresistive effect elements in the first magnetic detection element group and the second magnetic detection element group are different from each other, and the plurality of magnetoresistive effect elements of the first magnetic detection element group and the plurality of magnetoresistive effect elements of the second magnetic detection element group are arranged so that the magnetization directions thereof are symmetrical.
    Type: Application
    Filed: May 2, 2016
    Publication date: November 24, 2016
    Inventors: Fumihito KOIKE, Ichiro TOKUNAGA, Hirofumi OKUMURA, Yukiko YASUDA
  • Publication number: 20160313411
    Abstract: A magnetic sensor is provided in which in a case where magnetization amounts of the first ferromagnetic layer and the second ferromagnetic layer in the first magnetic sensor element are respectively set to be Mst11 and Mst12 and magnetization amounts of the first ferromagnetic layer and the second ferromagnetic layer in the second magnetic sensor element are respectively set to be Mst21 and Mst22, in a case of Mst11>Mst12, a relationship of Mst21>Mst22 is satisfied, and in a case of Mst11<Mst12, a relationship of Mst21<Mst22 is satisfied.
    Type: Application
    Filed: April 1, 2016
    Publication date: October 27, 2016
    Inventors: Fumihito KOIKE, Hirofumi OKUMURA, Eiji SHINOHARA, Kazuhiro SHIGETA, Taku SAITO
  • Patent number: 9207293
    Abstract: A magnetic sensor having no sensitivity differences between sensitivity axes, and an easy manufacturing method therefor are provided. The method includes a process of forming first stacked films for a magnetoresistive element on a substrate. This element has a sensitivity axis in a certain direction and includes a self-pinned ferromagnetic pinned layer in which first and second ferromagnetic films are antiferromagnetically coupled through an antiparallel coupling layer, a nonmagnetic intermediate layer, and a soft magnetic free layer. The method further includes a process of removing a region of the first stacked films from the substrate. The remaining region of the films includes at least a region to be left to form the element. The method furthermore includes a process of forming second stacked films for a magnetoresistive element, which has a sensitivity axis in a direction different from the certain direction and has the same structure, on the exposed substrate.
    Type: Grant
    Filed: May 8, 2012
    Date of Patent: December 8, 2015
    Assignee: ALPS ELECTRIC CO., LTD.
    Inventors: Hideto Ando, Shinji Sugihara, Fumihito Koike, Kota Asatsuma