Patents by Inventor Hiromi Yuasa

Hiromi Yuasa 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: 8199429
    Abstract: A magnetic recording head includes: a main magnetic pole containing a ferromagnetic layer; a main magnetic pole-magnetization fixing portion containing an antiferromagnetic layer in contact with at least one side surface of the main magnetic pole; a heater for heating at least the main magnetic pole so that a magnetic interaction between the main magnetic pole and the main magnetic pole-magnetization fixing portion can be decreased; and a magnetic field generator for generating a magnetic field so as to direct a magnetization of the main magnetic pole in one direction.
    Type: Grant
    Filed: March 18, 2008
    Date of Patent: June 12, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiromi Yuasa, Tomoko Taguchi, Hideaki Fukuzawa
  • Publication number: 20120129008
    Abstract: A magneto-resistance effect element, a magneto-resistance effect head, a magnetic storage and a magnetic memory, in which noise caused by a spin-transfer torque is reduced, are provided. In a fixed magnetization layer or a free magnetization layer of a magneto-resistance effect element including the fixed magnetization layer, a spacer layer and the free magnetization layer; a layer containing one element selected from the group consisting of Ti, Zr, Nb, Mo, Ru, Rh, Pd, Ag, La, Hf, Ta, W, Re, Os, Ir, Pt and Au is disposed.
    Type: Application
    Filed: January 27, 2012
    Publication date: May 24, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hideaki FUKUZAWA, Masahiro TAKASHITA, Hiromi YUASA, Yoshihiko FUJI, Hitoshi IWASAKI
  • Patent number: 8184408
    Abstract: A magnetoresistive element includes a magnetoresistive film including a magnetization pinned layer, a magnetization free layer, an intermediate layer arranged between the magnetization pinned layer and the magnetization free layer, a cap layer arranged on the magnetization pinned layer or on the magnetization free layer, and a functional layer formed of an oxygen- or nitrogen-containing material and arranged in the magnetization pinned layer, or in the magnetization free layer, and a pair of electrodes which pass a current perpendicularly to a plane of the magnetoresistive film, in which a crystalline orientation plane of the functional layer is different from a crystalline orientation plane of its upper or lower adjacent layer.
    Type: Grant
    Filed: January 30, 2009
    Date of Patent: May 22, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shuichi Murakami, Hideaki Fukuzawa, Hiromi Yuasa, Yoshihiko Fuji
  • Patent number: 8184410
    Abstract: An example magnetoresistive element includes a first magnetic layer whose magnetization direction is substantially pinned toward one direction; a second magnetic layer whose magnetization direction is changed in response to an external magnetic field; and a spacer layer provided between the first magnetic layer and the second magnetic layer. At least one of the first magnetic layer and the second magnetic layer has a magnetic compound that is expressed by M1aM2bXc(where 5?a?68, 10?b?73, and 22?c?85). M1 is at least one element selected from the group consisting of Co, Fe, and Ni. M2 is at least one element selected from the group consisting of Ti, V, Cr, and Mn. X is at least one element selected from the group consisting of N, O, and C.
    Type: Grant
    Filed: September 24, 2007
    Date of Patent: May 22, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshihiko Fuji, Hideaki Fukuzawa, Hiromi Yuasa
  • Patent number: 8169752
    Abstract: In a method for manufacturing a magneto-resistance effect element having a pinned magnetic layer of which a magnetization is fixed substantially in one direction, a free magnetization layer of which a magnetization is rotated in accordance with an external magnetic field and a spacer layer, which is located between the fixed magnetization layer and the free magnetization layer, with an insulating layer and a metallic layer penetrating through the insulating layer, the spacer layer is formed by forming a first metallic layer; forming, on the first metallic layer, a second metallic layer to be converted into a portion of the insulating layer; performing a first conversion treatment so as to convert the second metallic layer into the portion of said insulating layer and to form a portion of the metallic layer penetrating through the insulating layer; forming, on the insulating layer and the metallic layer formed through the first conversion treatment, a third metallic layer to be converted into the other portion
    Type: Grant
    Filed: July 6, 2007
    Date of Patent: May 1, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Yoshihiko Fuji
  • Patent number: 8153188
    Abstract: The present invention relates to a method for manufacturing a magnetoresistive element having a magnetization pinned layer, a magnetization free layer, and a spacer layer including an insulating layer provided between the magnetization pinned layer and the magnetization free layer and current paths penetrating into the insulating layer. A process of forming the spacer layer in the method includes depositing a first metal layer forming the metal paths, depositing a second metal layer on the first metal layer, performing a pretreatment of irradiating the second metal layer with an ion beam or a RF plasma of a rare gas, and converting the second metal layer into the insulating layer by means of supplying an oxidation gas or a nitriding gas.
    Type: Grant
    Filed: October 9, 2008
    Date of Patent: April 10, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Katsuhiko Koui, Hiromi Yuasa, Susumu Hashimoto, Hitoshi Iwasaki
  • Publication number: 20120079887
    Abstract: A strain sensor element comprises a laminated film which has a magnetic free layer, a spacer layer, and a magnetic reference layer. The free layer has a variable magnetization direction and a out-of-plane magnetization direction. The reference layer has a variable magnetization direction which is pinned more strongly than the magnetization of the free layer. The spacer layer provided between the free layer and the reference layer. A pair of electrodes is provided with a plane of the laminated film. A substrate is provided with either of the pair electrodes and can be strained. The rotation angle of the magnetization of the free layer is different from the rotation angle of the magnetization of the reference layer when the substrate is distorted. Electrical resistance is changed depending on the magnetization angle between the free layer and the reference layer, which allows the element to operate as a strain sensor.
    Type: Application
    Filed: May 18, 2011
    Publication date: April 5, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Alexander Devin Giddings, Hideaki Fukuzawa, Yoshihiko Fuji, Hiromi Yuasa, Michiko Hara, Shuichi Murakami
  • Patent number: 8130477
    Abstract: A magneto-resistance effect element, a magneto-resistance effect head, a magnetic storage and a magnetic memory, in which noise caused by a spin-transfer torque is reduced, are provided. In a fixed magnetization layer or a free magnetization layer of a magneto-resistance effect element including the fixed magnetization layer, a spacer layer and the free magnetization layer; a layer containing one element selected from the group consisting of Ti, Zr, Nb, Mo, Ru, Rh, Pd, Ag, La, Hf, Ta, W, Re, Os, Ir, Pt and Au is disposed.
    Type: Grant
    Filed: September 10, 2010
    Date of Patent: March 6, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Masahiro Takashita, Hiromi Yuasa, Yoshihiko Fuji, Hitoshi Iwasaki
  • Publication number: 20120050920
    Abstract: According to one embodiment, a method of manufacturing a magnetoresistive element includes a layered structure and a pair of electrodes, the layered structure including a cap layer, a magnetization pinned layer, a magnetization free layer, a spacer layer and a functional layer provided in the magnetization pinned layer, between the magnetization pinned layer and the spacer layer, between the spacer layer and the magnetization free layer, in the magnetization free layer, or between the magnetization free layer and the cap layer and including an oxide, the method including forming a film including a base material of the functional layer, performing an oxidation treatment on the film using a gas containing oxygen in a form of at least one selected from the group consisting of molecule, ion, plasma and radical, and performing a reduction treatment using a reducing gas on the film after the oxidation treatment.
    Type: Application
    Filed: July 19, 2011
    Publication date: March 1, 2012
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Akihiko Takeo, Yoshihiko Fuji, Hiromi Yuasa, Michiko Hara, Shuichi Murakami, Hideaki Fukuzawa
  • Patent number: 8111488
    Abstract: A magnetic multilayered film current element includes: at least one magnetic layer; at least one film structure containing a first insulating layer where a first opening is formed, a second insulating layer where a second opening is formed and a conductor disposed between the first insulating layer and the second insulating layer under the condition that a distance “A” between the first insulating layer and a portion of the second insulating layer at a position of the second opening is set larger than a closest distance “B” between the first insulating layer and the second insulating layer; and a pair of electrodes for flowing current to a magnetic multilayered film containing the at least one magnetic layer and the at least one film structure along a stacking direction of the magnetic multilayered film.
    Type: Grant
    Filed: June 11, 2008
    Date of Patent: February 7, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshihiko Fuji, Hideaki Fukuzawa, Hiromi Yuasa
  • Patent number: 8111489
    Abstract: An example method for manufacturing a magneto-resistance effect element includes: forming a first magnetic layer; forming a first metallic layer, on the first magnetic layer, mainly containing an element selected from the group consisting of Cu, Au, Ag; forming a functional layer, on the first metallic layer, mainly containing an element selected from the group consisting of Si, Hf, Ti, Mo, W, Nb, Mg, Cr and Zr; forming a second metallic layer, on the functional layer, mainly containing Al; treating the second metallic layer by oxidizing, nitriding or oxynitiriding so as to form a current confined layer including an insulating layer and a current path with a conductor passing a current through the insulating layer; and forming, on the current confined layer, a second magnetic layer.
    Type: Grant
    Filed: December 17, 2008
    Date of Patent: February 7, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshihiko Fuji, Hideaki Fukuzawa, Hiromi Yuasa
  • Publication number: 20120015214
    Abstract: A magneto-resistance effect element, comprising a first magnetic layer, a first metallic layer, which is formed on said first magnetic layer, mainly containing an element selected from the group consisting of Cu, Au, Ag, a current confined layer including an insulating layer and a current path which are made by oxidizing, nitriding or oxynitriding for a second metallic layer, mainly containing Al, formed on said first metallic layer, a functional layer, which is formed on said current confined layer, mainly containing an element selected from the group consisting of Si, Hf, Ti, Mo, W, Nb, Mg, Cr and Zr, a third metallic layer, which is formed on said functional layer, mainly containing an element selected from the group consisting of Cu, Au, Ag; and a second magnetic layer which is formed on said third metallic layer.
    Type: Application
    Filed: September 23, 2011
    Publication date: January 19, 2012
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Yoshihiko FUJI, Hideaki Fukuzawa, Hiromi Yuasa
  • Patent number: 8085511
    Abstract: A magnetoresistance effect element includes a magnetoresistance effect film including a magnetically pinned layer having a magnetic material film whose direction of magnetization is pinned substantially in one direction, a magnetically free layer having a magnetic material film whose direction of magnetization changes in response to an external magnetic field, and a nonmagnetic metal intermediate layer located between said pinned layer and said free layer. The element also includes a pair of electrodes electrically connected to the magnetoresistance effect film to supply a sense current perpendicularly to a film plane of the magnetoresistance effect film. At least one of the pinned layer and the free layer may include a thin-film insertion layer.
    Type: Grant
    Filed: September 23, 2008
    Date of Patent: December 27, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiromi Yuasa, Yuzo Kamiguchi, Masatoshi Yoshikawa, Katsuhiko Koui, Hitoshi Iwasaki, Tomohiko Nagata, Takeo Sakakubo, Masashi Sahashi
  • Publication number: 20110295128
    Abstract: A blood-pressure sensor includes a substrate, a first electrode, a magnetization fixed layer, a nonmagnetic layer, a magnetization free layer, and a second electrode. The substrate is bent to generate a tensile stress at least in a first direction. The first electrode is provided on the substrate. The magnetization fixed layer has magnetization to be fixed in a second direction, and is provided on the substrate. The nonmagnetic layer is provided on the magnetization fixed layer. The magnetization free layer has a magnetization direction which is different from the first direction and from a direction perpendicular to the first direction. The second electrode is provided on the magnetization free layer.
    Type: Application
    Filed: March 11, 2011
    Publication date: December 1, 2011
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Hiromi Yuasa, Hideaki Fukuzawa, Yoshihiko Fuji, Alexander Devin Giddings, Michiko Hara, Shuichi Murakami
  • Publication number: 20110265325
    Abstract: A novel CCP scheme is disclosed for a CPP-GMR sensor in which an amorphous metal/alloy layer such as Hf is inserted between a lower Cu spacer and an oxidizable layer such as Al, Mg, or AlCu prior to performing a pre-ion treatment (PIT) and ion assisted oxidation (IAO) to transform the amorphous layer into a first metal oxide template and the oxidizable layer into a second metal oxide template both having Cu metal paths therein. The amorphous layer promotes smoothness and smaller grain size in the oxidizable layer to minimize variations in the metal paths and thereby improves dR/R, R, and dR uniformity by 50% or more. An amorphous Hf layer may be used without an oxidizable layer, or a thin Cu layer may be inserted in the CCP scheme to form a Hf/PIT/IAO or Hf/Cu/Al/PIT/IAO configuration. A double PIT/IAO process may be used as in Hf/PIT/IAO/Al/PIT/IAO or Hf/PIT/IAO/Hf/PIT/IAO schemes.
    Type: Application
    Filed: July 11, 2011
    Publication date: November 3, 2011
    Inventors: Kunliang Zhang, Min Li, Yue Liu, Hideaki Fukuzawa, Hiromi Yuasa
  • Patent number: 8048492
    Abstract: A magnetoresistive effect element is produced by forming a first magnetic layer, a spacer layer including an insulating layer and a conductive layer which penetrates through the insulating layer and passes a current, on the first magnetic layer, and a second magnetic layer all of which or part of which is treated with ion, plasma or heat, on the formed spacer layer.
    Type: Grant
    Filed: December 20, 2006
    Date of Patent: November 1, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Yoshihiko Fuji, Hitoshi Iwasaki
  • Publication number: 20110261478
    Abstract: According to one embodiment, a magnetoresistive element includes a stack and a pair of electrodes that allows electric current to flow through the stack in a direction perpendicular to a surface of the stack. The stack includes a cap layer, a magnetization pinned layer, a magnetization free layer provided between the cap layer and the magnetization pinned layer, a tunneling insulator provided between the magnetization pinned layer and the magnetization free layer, and a functional layer provided within the magnetization pinned layer, between the magnetization pinned layer and the tunneling insulator, between the tunneling insulator and the magnetization free layer, within the magnetization free layer, or between the magnetization free layer and the cap layer. The functional layer includes an oxide including at least one element selected from Zn, In, Sn and Cd and at least one element selected from Fe, Co and Ni.
    Type: Application
    Filed: April 21, 2011
    Publication date: October 27, 2011
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Akihiko Takeo, Yoshihiko Fuji, Hiromi Yuasa, Michiko Hara, Shuichi Murakami, Hideaki Fukuzawa
  • Publication number: 20110228427
    Abstract: A magnetoresistive element includes a first ferromagnetic layer, a second ferromagnetic layer, a nonmagnetic layer, a first metal layer, a second metal layer, a first electrode, and a second electrode. The nonmagnetic layer is provided between the first ferromagnetic layer and the second ferromagnetic layer. The first metal layer includes Au and is provided so that the first ferromagnetic layer is sandwiched between the nonmagnetic layer and the first metal layer. The second metal layer includes a CuNi alloy, and is provided so that the first metal layer is sandwiched between the first ferromagnetic layer and the second metal layer. In addition, magnetization of either one of the first ferromagnetic layer and the second ferromagnetic layer is fixed in a direction. Magnetization of the other is variable in response to an external field. At least one of the first ferromagnetic layer and the second ferromagnetic layer includes a half metal.
    Type: Application
    Filed: September 10, 2010
    Publication date: September 22, 2011
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hiromi YUASA, Shuichi Murakami, Yoshihiko Fuji, Hideaki Fukuzawa
  • Publication number: 20110205669
    Abstract: According to one embodiment, a method for manufacturing a magneto-resistance effect element is disclosed. The element has first and second magnetic layers, and an intermediate layer provided between the first and second magnetic layers. The intermediate layer has an insulating layer and a conductive portion penetrating through the insulating layer. The method can include forming a structure body having the insulating layer and the conductive portion, performing a first treatment including irradiating the structure body with at least one of ion including at least one selected from the group consisting of argon, xenon, helium, neon and krypton and a plasma including at least one selected from the group, and performing a second treatment including at least one of exposure to gas containing oxygen or nitrogen, irradiation of ion beam containing oxygen or nitrogen, irradiation of plasma containing oxygen or nitrogen, to the structure body submitted to the first treatment.
    Type: Application
    Filed: September 14, 2010
    Publication date: August 25, 2011
    Applicants: Kabushiki Kaisha Toshiba, TDK CORPORATION
    Inventors: Shuichi Murakami, Hiromi Yuasa, Michiko Hara, Yoshihiko Fuji, Hideaki Fukuzawa, Kunliang Zhang, Min Li
  • Patent number: 7978442
    Abstract: A novel CCP scheme is disclosed for a CPP-GMR sensor in which an amorphous metal/alloy layer such as Hf is inserted between a lower Cu spacer and an oxidizable layer such as Al, Mg, or AlCu prior to performing a pre-ion treatment (PIT) and ion assisted oxidation (IAO) to transform the amorphous layer into a first metal oxide template and the oxidizable layer into a second metal oxide template both having Cu metal paths therein. The amorphous layer promotes smoothness and smaller grain size in the oxidizable layer to minimize variations in the metal paths and thereby improves dR/R, R, and dR uniformity by 50% or more. An amorphous Hf layer may be used without an oxidizable layer, or a thin Cu layer may be inserted in the CCP scheme to form a Hf/PIT/IAO or Hf/Cu/Al/PIT/IAO configuration. A double PIT/IAO process may be used as in Hf/PIT/IAO/Al/PIT/IAO or Hf/PIT/IAO/Hf/PIT/IAO schemes.
    Type: Grant
    Filed: October 3, 2007
    Date of Patent: July 12, 2011
    Assignees: TDK Corporation, Kabushiki Kaisha Toshiba
    Inventors: Kunliang Zhang, Min Li, Yue Liu, Hideaki Fukuzawa, Hiromi Yuasa