Patents by Inventor Hideaki Fukuzawa

Hideaki Fukuzawa 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: 7808330
    Abstract: A high-frequency oscillator includes a high-frequency oscillation element having a magnetization pinned layer whose magnetization direction is pinned substantially in one direction, an oscillation layer formed of a magnetic material which generates a high-frequency oscillation phenomenon when a current is supplied, an intermediate layer provided between the magnetization pinned layer and the oscillation layer, the intermediate layer having an insulation layer and current paths which pass through the insulation layer in a thickness direction, and a pair of electrodes which supply a current perpendicularly to a plane of a stacked film including the magnetization pinned layer, the intermediate layer and the oscillation layer.
    Type: Grant
    Filed: February 7, 2008
    Date of Patent: October 5, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Hitoshi Iwasaki
  • Publication number: 20100226048
    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: September 22, 2006
    Publication date: September 9, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hideaki Fukuzawa, Masahiro Takashita, Hiromi Yuasa, Yoshihiko Fuji, Hitoshi Iwasaki
  • Patent number: 7785662
    Abstract: There is provided a method for manufacturing a magnetoresistive element having a magnetization pinned layer, a magnetization free layer, and a spacer layer including an insulating layer arranged between the magnetization pinned layer and the magnetization free layer and current paths passing through the insulating layer. The method includes, in producing the spacer layer, depositing a first non-magnetic metal layer forming the current paths, depositing a second metal layer to be converted into the insulating layer on the first non-magnetic metal layer, and performing two stages of oxidation treatments in which a partial pressure of an oxidizing gas in a first oxidation treatment is set to 1/10 or less of a partial pressure of an oxidizing gas in a second oxidation treatment, and the second metal layer being irradiated with an ion beam or a RF plasma of a rare gas in the first oxidation treatment.
    Type: Grant
    Filed: October 20, 2006
    Date of Patent: August 31, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshihiko Fuji, Hideaki Fukuzawa, Hiromi Yuasa, Hitoshi Iwasaki
  • Patent number: 7776387
    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: Grant
    Filed: May 23, 2007
    Date of Patent: August 17, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshihiko Fuji, Hideaki Fukuzawa, Hiromi Yuasa
  • Patent number: 7742262
    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: August 31, 2007
    Date of Patent: June 22, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Hitoshi Iwasaki
  • Patent number: 7738220
    Abstract: A magnetoresistance effect element, comprising a nonmagnetic spacer layer, first and second ferromagnetic layers separated by the nonmagnetic spacer layer, the first ferromagnetic layer having a magnetization direction at an angle relative to a magnetization direction of the second ferromagnetic layer at zero applied magnetic field, the magnetization of the first ferromagnetic layer freely rotating in a magnetic field signal, a magnetoresistance effect-improving layer comprising a plurality of metal films and disposed in contact with the first ferromagnetic layer so that the first ferromagnetic layer is disposed between the nonmagnetic spacer layer and the magnetoresistance effect-improving layer, one of the plurality of metal films disposed in contact with the first ferromagnetic layer contains metal element of not solid solution with metal element of the first ferromagnetic layer and a nonmagnetic underlayer or a nonmagnetic protecting layer disposed in contact with the magnetoresistance effect-improving la
    Type: Grant
    Filed: July 17, 2007
    Date of Patent: June 15, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Yuzo Kamiguchi, Katsuhiko Koui, Shin-ichi Nakamura, Hitoshi Iwasaki, Kazuhiro Saito, Hiromi Fuke, Masatoshi Yoshikawa, Susumu Hashimoto, Masashi Sahashi
  • Patent number: 7719799
    Abstract: A magnetoresistive element has a first magnetic layer and a second magnetic layer separate from each other, the first magnetic layer and the second magnetic layer each having a magnetization whose direction is substantially pinned, and a non-magnetic conductive layer formed in contact with the first magnetic layer and the second magnetic layer and electrically connecting the first and second magnetic layers, the non-magnetic conductive layer forming a path of spin-polarized electrons from one of the magnetic layer to the other magnetic layer, the non-magnetic conductive layer comprising a portion located between the first magnetic layer and the second magnetic layer, the portion being a sensing area.
    Type: Grant
    Filed: December 5, 2008
    Date of Patent: May 18, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Susumu Hashimoto, Hitoshi Iwasaki
  • Publication number: 20100092803
    Abstract: A method for manufacturing a magneto-resistance effect element is provided. The magneto-resistance effect element includes a first magnetic layer including a ferromagnetic material, a second magnetic layer including a ferromagnetic material and a spacer layer provided between the first magnetic layer and the second magnetic layer, the spacer layer having an insulating layer and a conductive portion penetrating through the insulating layer. The method includes: forming a film to be a base material of the spacer layer; performing a first treatment using a gas including at least one of oxygen molecules, oxygen atoms, oxygen ions, oxygen plasma and oxygen radicals on the film; and performing a second treatment using a gas including at least one of hydrogen molecules, hydrogen atoms, hydrogen ions, hydrogen plasma, hydrogen radicals, deuterium molecules, deuterium atoms, deuterium ions, deuterium plasma and deuterium radicals on the film submitted to the first treatment.
    Type: Application
    Filed: September 25, 2009
    Publication date: April 15, 2010
    Applicants: KABUSHIKI KAISHA TOSHIBA, TDK CORPORATION
    Inventors: Hiromi Yuasa, Hideaki Fukuzawa, Yoshihiko Fuji, Shuichi Murakami, Michiko Hara, Kunliang Zhang, Min Li, Erhard Schreck
  • Publication number: 20100091414
    Abstract: A method for manufacturing a magneto-resistance effect element is provided. The magneto-resistance effect element includes a first magnetic layer including a ferromagnetic material, a second magnetic layer including a ferromagnetic material and a spacer layer provided between the first magnetic layer and the second magnetic layer, the spacer layer having an insulating layer and a conductive portion penetrating through the insulating layer. The method includes: forming a film to be a base material of the spacer layer; performing a first treatment using a gas including at least one of oxygen molecules, oxygen atoms, oxygen ions, oxygen plasma and oxygen radicals on the film; and performing a second treatment using a gas including at least one of krypton ions, krypton plasma, krypton radicals, xenon ions, xenon plasma and xenon radicals on the film submitted to the first treatment.
    Type: Application
    Filed: September 25, 2009
    Publication date: April 15, 2010
    Applicants: KABUSHIKI KAISHA TOSHIBA, TDK CORPORATION
    Inventors: Hiromi Yuasa, Hideaki Fukuzawa, Yoshihiko Fuji, Shuichi Murakami, Michiko Hara, Kunliang Zhang, Min Li, Erhard Schreck
  • Publication number: 20100091412
    Abstract: A method for manufacturing a magneto-resistance effect element is provided. The magneto-resistance effect element includes a first magnetic layer including a ferromagnetic material, a second magnetic layer including a ferromagnetic material and a spacer layer provided between the first magnetic layer and the second magnetic layer, the spacer layer having an insulating layer and a conductive portion penetrating through the insulating layer. The method includes: forming a film to be a base material of the spacer layer; performing a first treatment using a gas including at least one of oxygen molecules, oxygen atoms, oxygen ions, oxygen plasma and oxygen radicals on the film; and performing a second treatment using a gas including at least one of helium ions, helium plasma, helium radicals, neon ions, neon plasma and neon radicals on the film submitted to the first treatment.
    Type: Application
    Filed: September 25, 2009
    Publication date: April 15, 2010
    Applicants: KABUSHIKI KAISHA TOSHIBA, TDK CORPORATION
    Inventors: Hiromi Yuasa, Hideaki Fukuzawa, Yoshihiko Fuji, Shuichi Murakami, Michiko Hara, Kunliang Zhang, Min Li, Erhard Schreck
  • Publication number: 20100091415
    Abstract: A method for manufacturing a magneto-resistance effect element is provided. The magneto-resistance effect element includes a first magnetic layer including a ferromagnetic material, a second magnetic layer including a ferromagnetic material and a spacer layer provided between the first magnetic layer and the second magnetic layer, the spacer layer having an insulating layer and a conductive portion penetrating through the insulating layer. The method includes: forming a film to be a base material of the spacer layer; performing a first treatment using a gas including at least one of oxygen molecules, oxygen atoms, oxygen ions, oxygen plasma and oxygen radicals on the film; and performing a second treatment using a gas including at least one of nitrogen ions, nitrogen atoms, nitrogen plasma, and nitrogen radicals on the film submitted to the first treatment.
    Type: Application
    Filed: September 25, 2009
    Publication date: April 15, 2010
    Applicants: KABUSHIKI KAISHA TOSHIBA, TDK CORPORATION
    Inventors: Hiromi Yuasa, Hideaki Fukuzawa, Yoshihiko Fuji, Shuichi Murakami, Michiko Hara, Kunliang Zhang, Min Li, Erhard Schreck
  • Patent number: 7602592
    Abstract: A magnetoresistive element includes at least three metallic magnetic layers, connection layers each provided between the metallic magnetic layers, and electrodes which supply a current perpendicularly to a plane of a stack of the metallic magnetic layers and the connection layers. A magnetization direction of a lowermost or uppermost metallic magnetic layer of the metallic magnetic layers is pinned, and a magnetization direction of an intermediate metallic magnetic layer is twisted such that magnetization directions of the lowermost and the uppermost metallic magnetic layers are made substantially orthogonal to each other at zero external field.
    Type: Grant
    Filed: May 26, 2006
    Date of Patent: October 13, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Hitoshi Iwasaki
  • Patent number: 7593195
    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 nitride, oxinitride, phosphide, and fluoride.
    Type: Grant
    Filed: December 12, 2006
    Date of Patent: September 22, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Hiromi Fuke, Hitoshi Iwasaki, Masashi Sahashi
  • Publication number: 20090225477
    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: May 19, 2009
    Publication date: September 10, 2009
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Hideaki FUKUZAWA, Hiromi Yuasa, Hiromi Fuke, Hitoshi Iwasaki, Masashi Sahashi
  • Publication number: 20090190264
    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 arranged in the magnetization pinned layer, in the magnetization free layer, in the interface between the magnetization pinned layer and the intermediate layer, in the interface between the intermediate layer and the magnetization free layer, or in the interface between the magnetization pinned layer or the magnetization free layer and the cap layer, and a pair of electrodes which pass a current perpendicularly to a plane of the magnetoresistive film, in which the functional layer is formed of a layer including nitrogen and a metal material containing 5 atomic % or more of Fe.
    Type: Application
    Filed: January 30, 2009
    Publication date: July 30, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hideaki Fukuzawa, Shuichi Murakami, Hiromi Yuasa, Yoshihiko Fuji
  • Publication number: 20090190262
    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: Application
    Filed: January 30, 2009
    Publication date: July 30, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Shuichi Murakami, Hideaki Fukuzawa, Hiromi Yuasa, Yoshihiko Fuji
  • Publication number: 20090162698
    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: Application
    Filed: December 20, 2006
    Publication date: June 25, 2009
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Yoshihiko Fuji, Hitoshi Iwasaki
  • Publication number: 20090141408
    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 nitride, oxinitride, phosphide, and fluoride.
    Type: Application
    Filed: February 6, 2009
    Publication date: June 4, 2009
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Hiromi Fuke, Hitoshi Iwasaki, Masashi Sahashi
  • Publication number: 20090109581
    Abstract: There are provided a magnetoresistance effect element, a magnetic head, a magnetic head assembly and a magnetic recording system, which have high sensitivity and high reliability. The magnetoresistance effect element has two ferromagnetic layers, a non-magnetic layer provided between the ferromagnetic layers, and a layer containing an oxide or nitride as a principal component, wherein the layer containing the oxide or nitride as the principal component contains a magnetic transition metal element which does not bond to oxygen and nitrogen and which is at least one of Co, Fe and Ni.
    Type: Application
    Filed: December 31, 2008
    Publication date: April 30, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hideaki FUKUZAWA, Katsuhiko Koi, Hiromi Fuke, Hiroshi Tomita, Hitoshi Iwasaki, Masashi Sahashi
  • Patent number: 7525776
    Abstract: A magnetoresistive element has a magnetization pinned layer a magnetization direction of which is substantially pinned in one direction, a magnetization free layer a magnetization direction of which varies depending on an external field, and a spacer layer including an insulating layer provided between the magnetization pinned layer and the magnetization free layer and current paths penetrating the insulating layer, the magnetization pinned layer or magnetization free layer located under the spacer layer comprising crystal grains separated by grain boundaries extending across a thickness thereof, in which, supposing that an in-plane position of one end of each of the crystal grains is set to 0 and an in-plane position of a grain boundary adjacent to the other end of the crystal grain is set to 100, the current path corresponding the crystal grain is formed on a region in a range between 20 and 80 of the in-plane position.
    Type: Grant
    Filed: November 9, 2005
    Date of Patent: April 28, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideaki Fukuzawa, Hiromi Yuasa, Katsuhiko Koui, Hitoshi Iwasaki