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).

  • Publication number: 20080102315
    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: Application
    Filed: July 6, 2007
    Publication date: May 1, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Yoshihiko Fuji
  • Publication number: 20080088981
    Abstract: There is provided a practical magnetoresistance effect element which has an appropriate value of resistance, which can be sensitized and which has a small number of magnetic layers to be controlled, and a magnetic head and magnetic recording and/or reproducing system using the same. Ina magnetoresistance effect element wherein a sense current is caused to flow in a direction perpendicular to the plane of the film, if a pinned layer and a free layer have a stacked construction of a magnetic layer and a non-magnetic layer or a stacked construction of a magnetic layer and a magnetic layer, it is possible to provide a practical magnetoresistance effect element which has an appropriate value of resistance, which can be sensitized and which has a small number of magnetic layers, while effectively utilizing the scattering effect depending on spin.
    Type: Application
    Filed: November 23, 2007
    Publication date: April 17, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yuuzo Kamiguchi, Hiromi Yuasa, Tomohiko Nagata, Hiroaki Yoda
  • Patent number: 7359162
    Abstract: There is provided a practical magnetoresistance effect element which has an appropriate value of resistance, which can be sensitized and which has a small number of magnetic layers to be controlled, and a magnetic head and magnetic recording and/or reproducing system using the same. In a magnetoresistance effect element wherein a sense current is caused to flow in a direction perpendicular to the plane of the film, if a pinned layer and a free layer have a stacked construction of a magnetic layer and a non-magnetic layer or a stacked construction of a magnetic layer and a magnetic layer, it is possible to provide a practical magnetoresistance effect element which has an appropriate value of resistance, which can be sensitized and which has a small number of magnetic layers, while effectively utilizing the scattering effect depending on spin.
    Type: Grant
    Filed: October 22, 2004
    Date of Patent: April 15, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yuuzo Kamiguchi, Hiromi Yuasa, Tomohiko Nagata, Hiroaki Yoda
  • Publication number: 20080068765
    Abstract: A spin valve type magnetoresistive effect element for vertical electric conduction includes a magnetoresistive effect film in which a resistance adjustment layer made of a material containing conductive carriers not more than 1022/cm3 is inserted. Thus the resistance value of a portion in change of spin-relied conduction is raised to an adequate value, thereby to increase the resistance variable amount.
    Type: Application
    Filed: October 31, 2007
    Publication date: March 20, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hiromi Yuasa, Masatoshi Yoshikawa, Katsuhiko Koui, Hitoshi Iwasaki, Masashi Sahashi
  • Publication number: 20080068764
    Abstract: A magnetoresistance effect element comprises a magnetoresistance effect film and a pair of electrode. The magnetoresistance effect film having a first magnetic layer whose direction of magnetization is substantially pinned in one direction; a second magnetic layer whose direction of magnetization changes in response to an external magnetic field; a nonmagnetic intermediate layer located between the first and second magnetic layers; and a film provided in the first magnetic layer, in the second magnetic layer, at a interface between the first magnetic layer and the nonmagnetic intermediate layer, and/or at a interface between the second magnetic layer and the nonmagnetic intermediate layer, the film having a thickness not larger than 3 nanometers, and the film has as least one selected from the group consisting of oxide, nitride, oxinitride, phosphide, and fluoride.
    Type: Application
    Filed: October 31, 2007
    Publication date: March 20, 2008
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Hiromi Fuke, Hitoshi Iwasaki, Masashi Sahashi
  • Publication number: 20080062574
    Abstract: A magneto-resistance effect element includes a first magnetic layer of which a magnetization direction is fixed; a second magnetic layer of which a magnetization direction is fixed; an intermediate layer which is provided between said first magnetic layer and said second magnetic layer; and a pair of electrodes for flowing a current perpendicular to a film surface of the resultant laminated body comprised of said first magnetic layer, said second magnetic layer and said intermediate layer. The intermediate layer includes insulating portions and metallic portions containing at least one selected from the group consisting of Fe, Co, Ni, Cr and the metallic portions are contacted with the first magnetic layer and the second magnetic layer.
    Type: Application
    Filed: September 7, 2007
    Publication date: March 13, 2008
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Hiromi Yuasa, Hideaki Fukuzawa, Yoshihiko Fuji
  • Publication number: 20080062577
    Abstract: A magnetoresistance effect element comprises a magnetoresistance effect film and a pair of electrode. The magnetoresistance effect film having a first magnetic layer whose direction of magnetization is substantially pinned in one direction; a second magnetic layer whose direction of magnetization changes in response to an external magnetic field; a nonmagnetic intermediate layer located between the first and second magnetic layers; and a film provided in the first magnetic layer, in the second magnetic layer, at a interface between the first magnetic layer and the nonmagnetic intermediate layer, and/or at a interface between the second magnetic layer and the nonmagnetic intermediate layer, the film having a thickness not larger than 3 nanometers, and the film has as least one selected from the group consisting of oxide, nitride, oxinitride, phosphide, and fluoride.
    Type: Application
    Filed: October 31, 2007
    Publication date: March 13, 2008
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Hideaki FUKUZAWA, Hiromi Yuasa, Hiromi Fuke, Hitoshi Iwasaki, Masashi Sahashi
  • Publication number: 20080005891
    Abstract: A method for manufacturing a magneto-resistance effect element includes: forming a fixed magnetization layer; forming a free magnetization layer; and forming a spacer layer with an insulating layer and a non-magnetic metallic path penetrating through the insulating layer, includes: forming a first non-magnetic metallic layer; forming, a metallic layer on a surface of the first non-magnetic metallic layer; irradiating, onto the metallic layer, ions or plasma including at least one of oxygen and nitrogen and at least one selected from the group consisting of Ar, Xe, He, Ne, kr so as to convert the metallic layer into the insulating layer and the non-magnetic metallic path containing the first non-magnetic metallic layer; forming a second non-magnetic metallic layer on the non-magnetic metallic path; and irradiating ions or plasma onto at least one of the fixed magnetization layer, the first metallic layer, the metallic layer, the insulating layer converted from the second metallic layer and the second non-magne
    Type: Application
    Filed: July 5, 2007
    Publication date: January 10, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hiromi Yuasa, Hideaki Fukuzawa, Yoshihiko Fuji
  • Publication number: 20080008909
    Abstract: A 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 means of 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: Application
    Filed: May 23, 2007
    Publication date: January 10, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yoshihiko Fuji, Hideaki Fukuzawa, Hiromi Yuasa
  • Publication number: 20070297098
    Abstract: A magnetoresistive element includes a first magnetic layer a magnetization direction of which is substantially pinned, a second magnetic layer a magnetization direction of which varies depending on an external field, a magnetic spacer layer provided between the first magnetic layer and the second magnetic layer, and electrodes which supply a current perpendicularly to a plane of a stacked film including the first magnetic layer, the magnetic spacer layer and the second magnetic layer. In this element, the magnetization directions of the first and the second magnetic layers are substantially orthogonal at zero external field.
    Type: Application
    Filed: August 31, 2007
    Publication date: December 27, 2007
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Hitoshi Iwasaki
  • Patent number: 7307819
    Abstract: A magnetoresistive element includes a first magnetic layer a magnetization direction of which is substantially pinned, a second magnetic layer a magnetization direction of which varies depending on an external field, a magnetic spacer layer provided between the first magnetic layer and the second magnetic layer, and electrodes which supply a current perpendicularly to a plane of a stacked film including the first magnetic layer, the magnetic spacer layer and the second magnetic layer. In this element, the magnetization directions of the first and the second magnetic layers are substantially orthogonal at zero external field.
    Type: Grant
    Filed: July 28, 2005
    Date of Patent: December 11, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Hitoshi Iwasaki
  • Patent number: 7301733
    Abstract: A magnetoresistance effect element comprises a magnetoresistance effect film and a pair of electrode. The magnetoresistance effect film having a first magnetic layer whose direction of magnetization is substantially pinned in one direction; a second magnetic layer whose direction of magnetization changes in response to an external magnetic field; a nonmagnetic intermediate layer located between the first and second magnetic layers; and a film provided in the first magnetic layer, in the second magnetic layer, at a interface between the first magnetic layer and the nonmagnetic intermediate layer, and/or at a interface between the second magnetic layer and the nonmagnetic intermediate layer, the film having a thickness not larger than 3 nanometers, and the film has as least one selected from the group consisting of oxide, nitride, oxinitride, phosphide, and fluoride.
    Type: Grant
    Filed: March 28, 2003
    Date of Patent: November 27, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Hiromi Fuke, Hitoshi Iwasaki, Masashi Sahashi
  • Patent number: 7295407
    Abstract: A magnetoresistance effect element a stacked film including a magnetization fixed layer in which the direction of magnetization is substantially fixed to one direction, and a magnetization free layer in which the direction of magnetization varies in response to an external magnetic field, an electrode connected to a part of a principal plane of the stacked film, the magnetoresistance effect element having a resistance varying in response to a relative angle between the direction of magnetization in the magnetization fixed layer and the direction of magnetization in the magnetization free layer, a sense current detecting the variation of the resistance being applied to the film planes of the magnetization fixed layer and the magnetization free layer via the electrode in a direction substantially perpendicular to the magnetization fixed layer and the magnetization free layer.
    Type: Grant
    Filed: June 8, 2007
    Date of Patent: November 13, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiromi Yuasa, Hiroaki Yoda, Yuzo Kamiguchi, Tomohiko Nagata
  • Publication number: 20070253122
    Abstract: A magneto-resistive element includes: a first magnetic layer having a substantially fixed magnetization direction; a thin film layer disposed on the first magnetic layer and having at least one of oxide, nitride, oxynitride, and metal; and a second magnetic layer disposed on the thin film layer and having a substantially fixed magnetization direction.
    Type: Application
    Filed: April 5, 2007
    Publication date: November 1, 2007
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Yoshihiko Fuji, Hiromi Yuasa, Hitoshi Iwasaki
  • Patent number: 7289305
    Abstract: A magnetoresistive element has a magnetization pinned layer, a nonmagnetic spacer layer including a stack of a nonmagnetic metal layer, a resistance increasing layer and another nonmagnetic metal layer, a magnetization free layer having an fcc crystal structure, a cap layer having an fcc, an hcp, or a bcc crystal structure and having an interatomic distance between nearest neighbors greater than that of the magnetization free layer, and a pair of electrodes configured to provide a sense current in a direction substantially perpendicular to planes of the magnetization pinned layer, the nonmagnetic spacer layer, and the magnetization free layer.
    Type: Grant
    Filed: March 9, 2005
    Date of Patent: October 30, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiromi Fuke, Hideaki Fukuzawa, Hiromi Yuasa, Susumu Hashimoto, Hitoshi Iwasaki
  • Publication number: 20070230065
    Abstract: A magnetoresistance effect element a stacked film including a magnetization fixed layer in which the direction of magnetization is substantially fixed to one direction, and a magnetization free layer in which the direction of magnetization varies in response to an external magnetic field, an electrode connected to a part of a principal plane of the stacked film, the magnetoresistance effect element having a resistance varying in response to a relative angle between the direction of magnetization in the magnetization fixed layer and the direction of magnetization in the magnetization free layer, a sense current detecting the variation of the resistance being applied to the film planes of the magnetization fixed layer and the magnetization free layer via the electrode in a direction substantially perpendicular to the magnetization fixed layer and the magnetization free layer.
    Type: Application
    Filed: June 8, 2007
    Publication date: October 4, 2007
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hiromi YUASA, Hiroaki Yoda, Yuzo Kamiguchi, Tomohiko Nagata
  • Publication number: 20070223150
    Abstract: A magnetoresistive effect element includes a magnetization fixed layer including a first crystal grain, having a magnetization direction which is fixed substantially in one direction, a spacer layer arranged on the magnetization fixed layer and having an insulating layer and a metal conductor penetrating the insulating layer, and a magnetization free layer including a second crystal grain, arranged on the spacer layer to oppose the metal conductor and having a magnetization direction which changes corresponding to an external magnetic field.
    Type: Application
    Filed: October 13, 2006
    Publication date: September 27, 2007
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Yoshinari Kurosaki, Hiromi Yuasa, Yoshihiko Fuji, Hitoshi Iwasaki
  • Publication number: 20070202249
    Abstract: A method is for manufacturing a magnetoresistance effect element having a magnetization fixed layer, a non-magnetic intermediate layer, and a magnetization free layer being sequentially stacked. The method includes: forming at least a part of a magnetic layer that is to become either one of the magnetization fixed layer and the magnetization free layer; forming a function layer including at least one of an oxide, a nitride, and a fluoride on the part of the magnetic layer; and removing a part of the function layer by exposing the function layer to either one of an ion beam and plasma irradiation.
    Type: Application
    Filed: February 8, 2007
    Publication date: August 30, 2007
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hiromi Yuasa, Hideaki Fukuzawa, Yoshihiko Fuji, Hitoshi Iwasaki
  • Publication number: 20070188945
    Abstract: A magnetoresistive effect element includes a fixed magnetization layer; a free magnetization layer; a nonmagnetic spacer layer between the fixed magnetization layer and the free magnetization layer; and an insertion layer disposed on an opposite side of the free magnetization layer from the nonmagnetic spacer layer, wherein the first insulating layer has an oxide, a nitride, or an oxynitride including at least one kind of element selected from a group constituted of Al(aluminum), Si(silicon), Mg(magnesium), Ta(tantalum) and Zn(zinc) as a major constituent, and the insertion layer has an oxide, a nitride, or an oxynitride including at least one kind of element selected from a group constituted of Al(aluminum), Si(silicon), Mg(magnesium), Ta(tantalum) and Zn(zinc) as a major constituent.
    Type: Application
    Filed: February 6, 2007
    Publication date: August 16, 2007
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yoshihiko Fuji, Hideaki Fukuzawa, Hiromi Yuasa, Hitoshi Iwasaki
  • Publication number: 20070177310
    Abstract: A spin valve type magnetoresistive effect element for vertical electric conduction includes a magnetoresistive effect film in which a resistance adjustment layer made of a material containing conductive carriers not more than 1022/cm3 is inserted. Thus the resistance value of a portion in change of spin-relied conduction is raised to an adequate valve, thereby to increase the resistance variable amount.
    Type: Application
    Filed: April 9, 2007
    Publication date: August 2, 2007
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hiromi YUASA, Masatoshi Yoshikawa, Katsuhiko Koui, Hitoshi Iwasaki, Masashi Sahashi