Patents by Inventor Katsuya Miura

Katsuya Miura 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: 9602103
    Abstract: As a technique for attaining a reduction in power consumption, there is a technique for reducing power consumption using a spin wave. No specific proposal concerning spin wave generation, spin wave detection, and a latch technique for information has been made. A device applies an electric field to a first electrode of a nonmagnetic material using a thin line-shaped stacked body including a first ferromagnetic layer and a nonmagnetic layer to thereby generate a spin wave in the first ferromagnetic layer, and detects a phase or amplitude of the spin wave propagated in the first ferromagnetic layer using a second electrode of a ferromagnetic material with a magnetoresistance effect.
    Type: Grant
    Filed: May 22, 2013
    Date of Patent: March 21, 2017
    Assignee: Hitachi, Ltd.
    Inventors: Katsuya Miura, Susumu Ogawa, Kenchi Ito, Masaki Yamada
  • Patent number: 9564152
    Abstract: Provided are a magneto resistive effect element with a stable magnetization direction perpendicular to a film plane and with a controlled magnetoresistance ratio, and a magnetic memory using the magneto resistive effect element. Ferromagnetic layers 106 and 107 of the magneto resistive effect element are formed from a ferromagnetic material containing at least one type of 3d transition metal such that the magnetoresistance ratio is controlled, and the film thickness of the ferromagnetic layers is controlled on an atomic layer level such that the magnetization direction is changed from a direction in the film plane to a direction perpendicular to the film plane.
    Type: Grant
    Filed: March 25, 2014
    Date of Patent: February 7, 2017
    Assignee: TOHOKU UNIVERSITY
    Inventors: Hideo Ohno, Shoji Ikeda, Fumihiro Matsukura, Masaki Endoh, Shun Kanai, Hiroyuki Yamamoto, Katsuya Miura
  • Publication number: 20170025600
    Abstract: A magnetoresistive element includes a reference layer having a fixed magnetization direction and including a ferromagnetic material containing Fe or Co, a recording layer having a variable magnetization direction and including a ferromagnetic material, and one non-magnetic layer that is formed between the reference layer and the recording layer and that contains oxygen. One of the reference layer and the recording layer contains Fe. The three layers are arranged so that a magnetization direction of the one of the reference layer and the recording layer becomes perpendicular to a layer surface by an interfacial perpendicular magnetic anisotropy at an interface between the one of the reference layer and the recording layer and the one non-magnetic layer resulting from the one of the reference layer and the recording layer having a predetermined thickness. The one of the reference layer and the recording layer has a bcc structure.
    Type: Application
    Filed: August 30, 2016
    Publication date: January 26, 2017
    Applicant: TOHOKU UNIVERSITY
    Inventors: Hideo OHNO, Shoji IKEDA, Fumihiro MATSUKURA, Masaki ENDOH, Shun KANAI, Katsuya MIURA, Hiroyuki YAMAMOTO
  • Patent number: 9450177
    Abstract: There is provided a magnetoresistive element whose magnetization direction is stable in a direction perpendicular to the film surface and whose magnetoresistance ratio is controlled, as well as magnetic memory using such a magnetoresistive element. By having the material of a ferromagnetic layer forming the magnetoresistive element comprise a ferromagnetic material containing at least one type of 3d transition metal, or a Heusler alloy, to control the magnetoresistance ratio, and by controlling the thickness of the ferromagnetic layer on an atomic layer level, the magnetization direction is changed from being in-plane with the film surface to being perpendicular to the film surface.
    Type: Grant
    Filed: February 14, 2011
    Date of Patent: September 20, 2016
    Assignee: TOHOKU UNIVERSITY
    Inventors: Hideo Ohno, Shoji Ikeda, Fumihiro Matsukura, Masaki Endoh, Shun Kanai, Katsuya Miura, Hiroyuki Yamamoto
  • Publication number: 20160202330
    Abstract: Provided is a magnetic sensor device having a structure in which a plurality of MTJ structures, each using a ferromagnetic layer having an in-plane axis of easy magnetization and a ferromagnetic layer having a perpendicular axis of easy magnetization, are laminated. By a single device, magnetic fields in two or more directions can be sensed, or a plurality of magnetic field ranges including a small magnetic field and a relatively large magnetic field can be sensed.
    Type: Application
    Filed: September 9, 2013
    Publication date: July 14, 2016
    Applicant: Hitachi, Ltd.
    Inventors: Hiroyuki YAMAMOTO, Akihiko KANDORI, Katsuya MIURA
  • Publication number: 20160105176
    Abstract: As a technique for attaining a reduction in power consumption, there is a technique for reducing power consumption using a spin wave. No specific proposal concerning spin wave generation, spin wave detection, and a latch technique for information has been made. A device applies an electric field to a first electrode of a nonmagnetic material using a thin line-shaped stacked body including a first ferromagnetic layer and a nonmagnetic layer to thereby generate a spin wave in the first ferromagnetic layer, and detects a phase or amplitude of the spin wave propagated in the first ferromagnetic layer using a second electrode of a ferromagnetic material with a magnetoresistance effect.
    Type: Application
    Filed: May 22, 2013
    Publication date: April 14, 2016
    Inventors: Katsuya MIURA, Susumu OGAWA, Kenchi ITO, Masaki YAMADA
  • Patent number: 9153306
    Abstract: Provided is a tunnel magnetoresistive effect element such that a high TMR ratio and a low write current can be realized, and the thermal stability factor (E/kBT) of a recording layer and a pinned layer is increased while an increase in resistance of the element as a whole is suppressed, thus enabling a stable operation. On at least one of a recording layer 21 and a pinned layer 22 each comprising CoFeB, electrically conductive oxide layers 31 and 32 are disposed on a side opposite to a tunnel barrier layer 10.
    Type: Grant
    Filed: November 8, 2011
    Date of Patent: October 6, 2015
    Assignee: TOHOKU UNIVERSITY
    Inventors: Hideo Ohno, Shoji Ikeda, Hiroyuki Yamamoto, Yosuke Kurosaki, Katsuya Miura
  • Patent number: 9135973
    Abstract: Provided are a magnetoresistance effect element with a stable magnetization direction perpendicular to film plane and a controlled magnetoresistance ratio, in which writing can be performed by magnetic domain wall motion, and a magnetic memory including the magnetoresistance effect element. The magnetoresistance ratio is controlled by forming a ferromagnetic layer of the magnetoresistance effect element from a ferromagnetic material including at least one type of 3d transition metal or a Heusler alloy. The magnetization direction is changed from a direction in the film plane to a direction perpendicular to the film plane by controlling the film thickness of the ferromagnetic layer on an atomic layer level.
    Type: Grant
    Filed: May 26, 2011
    Date of Patent: September 15, 2015
    Assignee: TOHOKU UNIVERSITY
    Inventors: Hideo Ohno, Shoji Ikeda, Fumihiro Matsukura, Masaki Endoh, Shun Kanai, Katsuya Miura, Hiroyuki Yamamoto
  • Patent number: 9070457
    Abstract: In magnetic tunnel junctions manufactured with use of a ferromagnetic material having perpendicular magnetic anisotropy, a difference in record retention time depending on stored information due to an imbalance in thermal stability between a parallel state and an anti-parallel state of magnetization, which correspond to bit information, is alleviated. A reference layer and a recording layer which constitute a magnetic tunnel junction are made different in area from each other so as to correct the difference in record retention time corresponding to stored information.
    Type: Grant
    Filed: May 24, 2012
    Date of Patent: June 30, 2015
    Assignee: Tohoku University
    Inventors: Hideo Ohno, Shoji Ikeda, Michihiko Yamanouchi, Hideo Sato, Katsuya Miura
  • Patent number: 8957486
    Abstract: Provided is a magnetic random access memory to which spin torque magnetization reversal is applied, the magnetic random access memory being thermal stable in a reading operation and also being capable of reducing a current in a wiring operation. A magnetoresistive effect element formed by sequentially stacking a fixed layer, a nonmagnetic barrier layer, and a recording layer is used as a memory element. The recording layer adopts a laminated ferrimagnetic structure.
    Type: Grant
    Filed: March 4, 2009
    Date of Patent: February 17, 2015
    Assignee: Hitachi, Ltd.
    Inventors: Kenchi Ito, Jun Hayakawa, Katsuya Miura, Hiroyuki Yamamoto
  • Patent number: 8917541
    Abstract: Provided are a magneto resistive effect element with a stable magnetization direction perpendicular to a film plane and with a controlled magnetoresistance ratio, and a magnetic memory using the magneto resistive effect element. Ferromagnetic layers 106 and 107 of the magneto resistive effect element are formed from a ferromagnetic material containing at least one type of 3d transition metal such that the magnetoresistance ratio is controlled, and the film thickness of the ferromagnetic layers is controlled on an atomic layer level such that the magnetization direction is changed from a direction in the film plane to a direction perpendicular to the film plane.
    Type: Grant
    Filed: May 31, 2011
    Date of Patent: December 23, 2014
    Assignees: Hitachi, Ltd., Tohoku University
    Inventors: Hideo Ohno, Shoji Ikeda, Fumihiro Matsukura, Masaki Endoh, Shun Kanai, Hiroyuki Yamamoto, Katsuya Miura
  • Publication number: 20140340961
    Abstract: Provided is a tunnel magnetoresistive effect element such that a high TMR ratio and a low write current can be realized, and the thermal stability factor (E/kBT) of a recording layer and a pinned layer is increased while an increase in resistance of the element as a whole is suppressed, thus enabling a stable operation. On at least one of a recording layer 21 and a pinned layer 22 each comprising CoFeB, electrically conductive oxide layers 31 and 32 are disposed on a side opposite to a tunnel barrier layer 10.
    Type: Application
    Filed: November 8, 2011
    Publication date: November 20, 2014
    Applicants: HITACHI, LTD., TOHOKU UNIVERSITY
    Inventors: Hideo Ohno, Shoji Ikeda, Hiroyuki Yamamoto, Yosuke Kurosaki, Katsuya Miura
  • Patent number: 8837209
    Abstract: A relation between a drive current of a selection transistor of a magnetic memory and a threshold magnetization switching current of the magnetoresistance effect element is optimized. In order to optimize the relation between the drive current of the selection transistor and the threshold magnetization switching current of the magnetoresistance effect element 101 of the magnetic memory cell, a mechanism 601-604 for dropping the threshold magnetization switching current on “1” writing is provided that applies a magnetic field that is in the inverse direction of the pinned layer to the recording layer of the magnetoresistance effect element.
    Type: Grant
    Filed: February 17, 2011
    Date of Patent: September 16, 2014
    Assignees: Hitachi, Ltd., Tohoku University
    Inventors: Hideo Ohno, Shoji Ikeda, Katsuya Miura, Kazuo Ono, Riichiro Takemura, Hiromasa Takahashi
  • Publication number: 20140205862
    Abstract: Provided are a magneto resistive effect element with a stable magnetization direction perpendicular to a film plane and with a controlled magnetoresistance ratio, and a magnetic memory using the magneto resistive effect element. Ferromagnetic layers 106 and 107 of the magneto resistive effect element are formed from a ferromagnetic material containing at least one type of 3d transition metal such that the magnetoresistance ratio is controlled, and the film thickness of the ferromagnetic layers is controlled on an atomic layer level such that the magnetization direction is changed from a direction in the film plane to a direction perpendicular to the film plane.
    Type: Application
    Filed: March 25, 2014
    Publication date: July 24, 2014
    Applicant: Tohoku University
    Inventors: Hideo Ohno, Shoji Ikeda, Fumihiro Matsukura, Masaki Endoh, Shun Kanai, Hiroyuki Yamamoto, Katsuya Miura
  • Publication number: 20130141966
    Abstract: Provided are a magnetoresistance effect element with a stable magnetization direction perpendicular to film plane and a controlled magnetoresistance ratio, in which writing can be performed by magnetic domain wall motion, and a magnetic memory including the magnetoresistance effect element. The magnetoresistance ratio is controlled by forming a ferromagnetic layer of the magnetoresistance effect element from a ferromagnetic material including at least one type of 3d transition metal or a Heusler alloy. The magnetization direction is changed from a direction in the film plane to a direction perpendicular to the film plane by controlling the film thickness of the ferromagnetic layer on an atomic layer level.
    Type: Application
    Filed: May 26, 2011
    Publication date: June 6, 2013
    Inventors: Hideo Ohno, Shoji Ikeda, Fumihiro Matsukura, Masaki Endoh, Shun Kanai, Katsuya Miura, Hiroyuki Yamamoto
  • Publication number: 20130094284
    Abstract: Provided are a magneto resistive effect element with a stable magnetization direction perpendicular to a film plane and with a controlled magnetoresistance ratio, and a magnetic memory using the magneto resistive effect element. Ferromagnetic layers 106 and 107 of the magneto resistive effect element are formed from a ferromagnetic material containing at least one type of 3d transition metal such that the magnetoresistance ratio is controlled, and the film thickness of the ferromagnetic layers is controlled on an atomic layer level such that the magnetization direction is changed from a direction in the film plane to a direction perpendicular to the film plane.
    Type: Application
    Filed: May 31, 2011
    Publication date: April 18, 2013
    Inventors: Hideo Ohno, Shoji Ikeda, Fumihiro Matsukura, Masaki Endoh, Shun Kanai, Hiroyuki Yamamoto, Katsuya Miura
  • Patent number: 8409074
    Abstract: A sleeping state improvement system to improve a sleeping state of a user includes a memory device and a control device that comprises a specification unit and a control unit. The memory device can be carried by the user. The specification unit specifies individual attribute information of the user based on individual information. The individual information is information stored in the memory device. The control unit controls an environment during sleep of the user based on the individual attribute information.
    Type: Grant
    Filed: September 14, 2005
    Date of Patent: April 2, 2013
    Assignee: Daikin Industries, Ltd.
    Inventors: Junichiro Arai, Katsuya Miura, Takayuki Ishiwata, Masahiro Tanaka
  • Publication number: 20130058156
    Abstract: A relation between a drive current of a selection transistor of a magnetic memory and a threshold magnetization switching current of the magnetoresistance effect element is optimized. In order to optimize the relation between the drive current of the selection transistor and the threshold magnetization switching current of the magnetoresistance effect element 101 of the magnetic memory cell, a mechanism 601-604 for dropping the threshold magnetization switching current on “1” writing is provided that applies a magnetic field that is in the inverse direction of the pinned layer to the recording layer of the magnetoresistance effect element.
    Type: Application
    Filed: February 17, 2011
    Publication date: March 7, 2013
    Inventors: Hideo Ohno, Shoji Ikeda, Katsuya Miura, Kazuo Ono
  • Publication number: 20120320666
    Abstract: There is provided a magnetoresistive element whose magnetization direction is stable in a direction perpendicular to the film surface and whose magnetoresistance ratio is controlled, as well as magnetic memory using such a magnetoresistive element. By having the material of a ferromagnetic layer forming the magnetoresistive element comprise a ferromagnetic material containing at least one type of 3d transition metal, or a Heusler alloy, to control the magnetoresistance ratio, and by controlling the thickness of the ferromagnetic layer on an atomic layer level, the magnetization direction is changed from being in-plane with the film surface to being perpendicular to the film surface.
    Type: Application
    Filed: February 14, 2011
    Publication date: December 20, 2012
    Applicants: Tohoku University, Hitachi, Ltd.
    Inventors: Hideo Ohno, Shoji Ikeda, Fumihiro Matsukura, Masaki Endoh, Shun Kanai, Katsuya Miura, Hiroyuki Yamamoto
  • Publication number: 20120300543
    Abstract: In magnetic tunnel junctions manufactured with use of a ferromagnetic material having perpendicular magnetic anisotropy, a difference in record retention time depending on stored information due to an imbalance in thermal stability between a parallel state and an anti-parallel state of magnetization, which correspond to bit information, is alleviated. A reference layer and a recording layer which constitute a magnetic tunnel junction are made different in area from each other so as to correct the difference in record retention time corresponding to stored information.
    Type: Application
    Filed: May 24, 2012
    Publication date: November 29, 2012
    Inventors: Hideo Ohno, Shoji Ikeda, Michihiko Yamanouchi, Hideo Sato, Katsuya Miura