Patents by Inventor Hideo Ohno

Hideo Ohno 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: 20180108390
    Abstract: A magnetoresistance effect element includes a recording layer containing a ferromagnetic body, and including a first fixed and second magnetization regions having magnetization components fixed substantially in a direction antiparallel to the in-plane direction to each other, and a free magnetization region disposed between the first and second fixed magnetization regions and having a magnetization component invertible in the in-plane direction, a domain wall disposed between the first fixed magnetization region and the free magnetization region, and being movable within the free magnetization region, and a magnetic nanowire having a width of 40 nm or less. The thickness of the recording layer is 40 nm or less and at least half but no more than twofold the width of the magnetic nanowire. The element further includes a barrier layer disposed on the recording layer, and a reference layer disposed on the barrier layer and containing a ferromagnetic body.
    Type: Application
    Filed: November 13, 2017
    Publication date: April 19, 2018
    Applicant: TOHOKU UNIVERSITY
    Inventors: Shunsuke FUKAMI, Toru IWABUCHI, Hideo OHNO, Tetsuo ENDOH
  • Patent number: 9941468
    Abstract: A magnetoresistance effect element (100) includes a heavy metal layer (11) that includes a heavy metal and that is formed to extend in a first direction, a recording layer (12) that includes a ferromagnetic material and that is provided adjacent to the heavy metal layer (11), a barrier layer (13) that includes an insulating material and that is provided on the recording layer (12) with being adjacent to a surface of the recording layer (12) opposite to the heavy metal layer (11), and a reference layer (14) that includes a ferromagnetic material and that is provided adjacent to a surface of the barrier layer (13), the surface being opposite to the recording layer (12). The direction of the magnetization of the reference layer (14) has a component substantially fixed in the first direction, and the direction of the magnetization of the recording layer (12) has a component variable in the first direction.
    Type: Grant
    Filed: July 29, 2015
    Date of Patent: April 10, 2018
    Assignee: Tohoku University
    Inventors: Shunsuke Fukami, Chaoling Zhang, Tetsuro Anekawa, Hideo Ohno, Tetsuo Endoh
  • Patent number: 9928906
    Abstract: A data-write device includes a write driver that causes a current to flow through a current path including an MTJ element or the other current path including the MTJ element in accordance with writing data to be written, thereby writing the write data into the MTJ element, a write completion detector which monitors the voltage at a first connection node or a second connection node in accordance with the write data after the writing of the write data into the MTJ element starts, detects the completion of writing of the write data based on the voltage at either node, and supplies a write completion signal indicating the completion of data write, and a write controller that terminates the writing of the write data into the MTJ element in response to the write completion signal supplied from the write completion detector.
    Type: Grant
    Filed: March 24, 2015
    Date of Patent: March 27, 2018
    Assignee: Tohoku University
    Inventors: Takahiro Hanyu, Daisuke Suzuki, Masanori Natsui, Akira Mochizuki, Hideo Ohno, Tetsuo Endoh
  • Publication number: 20180019388
    Abstract: A magnetoresistance effect element includes a bias layer comprised of an antiferromagnetic material and having a shape in which a first length in a first direction greater than a second length in a second direction perpendicular to the first direction, a recording layer comprised of a ferromagnetic material and being disposed on the bias layer, a direction of magnetization of the recording layer being reversible, a barrier layer comprised of an insulation material and being disposed on the recording layer, and a reference layer comprised of a ferromagnetic material and being disposed on the barrier layer, a direction of magnetization of the reference layer being substantially fixed.
    Type: Application
    Filed: September 28, 2017
    Publication date: January 18, 2018
    Applicant: TOHOKU UNIVERSITY
    Inventors: Shunsuke FUKAMI, Hideo OHNO, Tetsuo ENDOH
  • Publication number: 20170365338
    Abstract: A data-write device includes a write driver that causes a current to flow through a current path including an MTJ element or the other current path including the MTJ element in accordance with writing data to be written, thereby writing the write data into the MTJ element, a write completion detector which monitors the voltage at a first connection node or a second connection node in accordance with the write data after the writing of the write data into the MTJ element starts, detects the completion of writing of the write data based on the voltage at either node, and supplies a write completion signal indicating the completion of data write, and a write controller that terminates the writing of the write data into the MTJ element in response to the write completion signal supplied from the write completion detector.
    Type: Application
    Filed: March 24, 2015
    Publication date: December 21, 2017
    Inventors: Takahiro Hanyu, Daisuke Suzuki, Masanori Natsui, Akira Mochizuki, Hideo Ohno, Tetsuo Endoh
  • Publication number: 20170324030
    Abstract: A magnetoresistance effect element includes a reference layer made of a ferromagnetic material, a recording layer made of a ferromagnetic material, and a barrier layer disposed between the reference layer and the recording layer. The reference layer and the recording layer have an in-plane magnetization direction parallel to a surface of the layers. The recording layer has a shape that has short axis and long axis perpendicular to the short axis in plan view. A first value obtained by dividing a thickness of the recording layer by a length of the short axis of the recording layer is greater than 0.3 and smaller than 1.
    Type: Application
    Filed: July 22, 2017
    Publication date: November 9, 2017
    Applicant: TOHOKU UNIVERSITY
    Inventors: Hideo SATO, Shinya ISHIKAWA, Shunsuke FUKAMI, Shoji IKEDA, Fumihiro MATSUKURA, Hideo OHNO, Tetsuo ENDOH
  • Publication number: 20170316724
    Abstract: Provided are a magnetic fluid composite for display use which enables visually recognizing a subtle shape caused by a spiking phenomenon and which can exhibit a color other than black, and a magnetic fluid composite display device. A magnetic fluid composite 1 for display use contains water 10, an oily magnetic fluid 20 and poorly magnetic light shielding pieces 30. The light shielding pieces 30 have a flake shape and include respectively hydrophilic layers 31, light shielding layers 33 and hydrophilic layers 35 that are laminated in the written order. The light shielding pieces 30 are arranged along the interface 1i between the water 10 and the oily magnetic fluid 20 so that the interface 1i between the water 10 and the oily magnetic fluid 20 is covered with a number of the light shielding pieces 30.
    Type: Application
    Filed: May 14, 2015
    Publication date: November 2, 2017
    Applicant: SHIGMA HI-CHEMICAL INC.
    Inventors: Hideo OHNO, Daiki INAMURA
  • Patent number: 9799822
    Abstract: A disclosed magnetic memory element includes: a magnetization free layer formed of a ferromagnetic substance having perpendicular magnetic anisotropy; a response layer provided so as to be opposed to the magnetization free layer and formed of a ferromagnetic substance having perpendicular magnetic anisotropy; a non-magnetic layer provided so as to be opposed to the response layer on a side opposite to the magnetization free layer and formed of a non-magnetic substance; and a reference layer provided so as to be opposed to the non-magnetic layer on a side opposite to the response layer and formed of a ferromagnetic substance having perpendicular magnetic anisotropy. The magnetization free layer includes a first magnetization fixed region and a second magnetization fixed region which have magnetization fixed in directions antiparallel to each other, and a magnetization free region in which a magnetization direction is variable.
    Type: Grant
    Filed: April 19, 2012
    Date of Patent: October 24, 2017
    Assignees: NEC CORPORATION, TOHOKU UNIVERSITY
    Inventors: Shunsuke Fukami, Nobuyuki Ishiwata, Tadahiko Sugibayashi, Hideo Ohno, Shoji Ikeda, Michihiko Yamanouchi
  • Publication number: 20170263854
    Abstract: A method of manufacturing a spintronics element from laminated layers. The method includes (a) forming a plurality of laminated layers in manufacturing equipment, (b) forming a wafer in the manufacturing equipment, including applying a protection layer directly on a non-magnetic uppermost layer of the laminated layers so that the protection layer prevents alteration of characteristics of the uppermost layer, and (c) exposing the wafer, outside of the manufacturing equipment, to an atmosphere that includes H2O having a partial pressure in the atmosphere equal to or larger than 10?4 Pa.
    Type: Application
    Filed: March 8, 2016
    Publication date: September 14, 2017
    Applicant: TOHOKU UNIVERSITY
    Inventors: Soshi SATO, Masaaki NIWA, Hiroaki HONJO, Shoji IKEDA, Hideo OHNO, Tetsuo ENDO
  • Publication number: 20170249981
    Abstract: In order to stably write data into a magnetic memory that uses in-plane current-induced perpendicular switching of magnetization to write data, the magnetic memory includes a recording layer formed as a perpendicular magnetization film, an adjacent layer joined to an upper surface or a lower surface of the recording layer, an external magnetic field application part configured to apply a first external magnetic field to the recording layer in a first direction which is an in-plane direction of the recording layer, and a current application part configured to allow a write current to flow through the adjacent layer in the first direction or a second direction which is opposite to the first direction. The external magnetic field application part is configured to switch a direction of a second external magnetic field applied in a direction perpendicular to the first direction in accordance with a direction of the write current.
    Type: Application
    Filed: August 31, 2015
    Publication date: August 31, 2017
    Applicants: NEC Corporation, TOHOKU UNIVERSITY
    Inventors: Ryusuke NEBASHI, Noboru SAKIMURA, Yukihide TSUJI, Ayuka TADA, Hideo OHNO
  • Publication number: 20170222135
    Abstract: A magnetoresistance effect element (100) includes a heavy metal layer (11) that includes a heavy metal and that is formed to extend in a first direction, a recording layer (12) that includes a ferromagnetic material and that is provided adjacent to the heavy metal layer (11), a barrier layer (13) that includes an insulating material and that is provided on the recording layer (12) with being adjacent to a surface of the recording layer (12) opposite to the heavy metal layer (11), and a reference layer (14) that includes a ferromagnetic material and that is provided adjacent to a surface of the barrier layer (13), the surface being opposite to the recording layer (12). The direction of the magnetization of the reference layer (14) has a component substantially fixed in the first direction, and the direction of the magnetization of the recording layer (12) has a component variable in the first direction.
    Type: Application
    Filed: July 29, 2015
    Publication date: August 3, 2017
    Inventors: Shunsuke Fukami, Chaoling Zhang, Tetsuro Anekawa, Hideo Ohno, Tetsuo Endoh
  • Publication number: 20170110654
    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 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: December 28, 2016
    Publication date: April 20, 2017
    Applicant: TOHOKU UNIVERSITY
    Inventors: Hideo OHNO, Shoji IKEDA, Fumihiro MATSUKURA, Masaki ENDOH, Shun KANAI, Hiroyuki YAMAMOTO, Katsuya MIURA
  • Patent number: 9577182
    Abstract: A magnetoresistance effect element and a magnetic memory having thermal stability expressed by a thermal stability factor of 70 or more even with a fine junction size. The magnetoresistance effect element includes a first magnetic layer of an invariable magnetization direction forming a reference layer, a second magnetic layer of a variable magnetization direction forming a recording layer, and a first non-magnetic layer disposed between the first and second magnetic layers in a thickness direction of the first and second magnetic layers. At least one of the first and second magnetic layers has the following relationship between D (nm) and t (nm): D<0.9t+13, where D is a junction size corresponding to the length of a longest straight line on an end surface perpendicular to the thickness direction, and t is a layer thickness. The junction size is 30 nm or less.
    Type: Grant
    Filed: October 20, 2014
    Date of Patent: February 21, 2017
    Assignee: TOHOKU UNIVERSITY
    Inventors: Shoji Ikeda, Hideo Sato, Shunsuke Fukami, Michihiko Yamanouchi, Fumihiro Matsukura, Hideo Ohno, Shinya Ishikawa
  • 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: 9536584
    Abstract: A nonvolatile logic gate device is configured to include a resistive network of a memory structure in which at least three nonvolatile resistive elements are connected, a reference resistive network as a reference resistance providing a tolerance of the memory structure to a resistance value of the resistive network of the memory structure, a writing part operable to selectively write or rewrite a value of each of the nonvolatile resistive elements in the resistive network into a maximum or a minimum corresponding to a logical value to be read when data are stored into the resistive network, and a logic circuit structure operable to use, as a logical value of the memory structure, a value obtained by comparison between the resistance value of the resistive network and the resistance value of the reference resistive network.
    Type: Grant
    Filed: May 15, 2013
    Date of Patent: January 3, 2017
    Assignees: NEC CORPORATION, TOHOKU UNIVERSITY
    Inventors: Ryusuke Nebashi, Noboru Sakimura, Yukihide Tsuji, Ayuka Tada, Tadahiko Sugibayashi, Takahiro Hanyu, Tetsuo Endoh, Hideo Ohno
  • Publication number: 20160329086
    Abstract: A control method for a magnetoresistance effect element and a control device for the magnetoresistance effect element that provide a higher writing speed and lower power consumption. When the magnetization direction of a second magnetic layer is nearly parallel to the magnetization direction of a first magnetic layer, a first voltage is applied across the first and second magnetic layer so that the magnetization direction of the second magnetic layer is reversed by modifying the direction of the magnetization easy axis thereof, followed by the application of a second voltage. When the magnetization direction of the second magnetic layer is nearly antiparallel to the magnetization direction of the first magnetic layer, a third voltage is applied across the first magnetic layer and the second magnetic layer, followed by the application of a fourth voltage so that current flows from the second magnetic layer toward the first magnetic layer.
    Type: Application
    Filed: November 13, 2014
    Publication date: November 10, 2016
    Applicant: Tohoku University
    Inventors: Shun KANAI, Fumihiro MATSUKURA, Hideo OHNO, Michihiko YAMANOUCHI, Shoji IKEDA, Hideo SATO
  • Patent number: 9478309
    Abstract: Provided is a magnetic domain wall displacement memory cell, including a recording layer including a magnetic film, the recording layer including: a magnetization reversal region in which magnetization is reversible; and first and second magnetization fixed regions that supply a spin-polarized electron to the magnetization reversal region. The magnetic domain wall displacement memory cell is configured so that a first region in which magnetization reversal occurs due to a first current flowing in a direction parallel to a film surface of the recording layer and a first magnetic field component in the direction parallel to the film surface of the recording layer is formed, and a second region in which no magnetization reversal occurs is formed.
    Type: Grant
    Filed: September 13, 2013
    Date of Patent: October 25, 2016
    Assignees: NEC CORPORATION, TOHOKU UNIVERSITY
    Inventors: Ryusuke Nebashi, Noboru Sakimura, Tadahiko Sugibayashi, Yukihide Tsuji, Ayuka Tada, Hiroaki Honjou, Hideo Ohno
  • Patent number: 9466363
    Abstract: An integrated circuit that does not involve increase in power consumption or decrease in switching probability during a write operation that occur when a latch circuit using STT-MTJ device, etc. of the prior art is operated at high speed is provided. The integrated circuit 1 includes: a memory element 1B where write occurs when a specified period ? has elapsed after a write signal is input; and a basic circuit element 1A, which is an elementary device constituting a circuit and has a data retaining function, and characterized in that an operation frequency f1 in a first operation mode in the process of memory access of the basic circuit element 1A satisfies the following relation: ?>?1/f1(0<?1?1).
    Type: Grant
    Filed: December 4, 2012
    Date of Patent: October 11, 2016
    Assignee: TOHOKU UNIVERSITY
    Inventors: Tetsuo Endoh, Takashi Ohsawa, Hiroki Koike, Takahiro Hanyu, Hideo Ohno
  • 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