Patents by Inventor Shunsuke Fukami

Shunsuke Fukami 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: 20180175286
    Abstract: A magnetoresistance effect element includes first and second magnetic layers having a perpendicular magnetization direction, and a first non-magnetic layer disposed adjacent to the first magnetic layer and on a side opposite to a side on which the second magnetic layer is disposed. An interfacial perpendicular magnetic anisotropy exists at an interface between the first magnetic layer and the first non-magnetic layer, and the anisotropy causes the first magnetic layer to have a magnetization direction perpendicular to the surface if the layers. The second magnetic layer has a saturation magnetization lower than that of the first magnetic layer, and an interfacial magnetic anisotropy energy density (Ki) at the interface between the first magnetic layer and the first non-magnetic layer is greater than that of an interface between the first non-magnetic layer and second magnetic layers if being disposed adjacent each other.
    Type: Application
    Filed: January 16, 2018
    Publication date: June 21, 2018
    Applicant: TOHOKU UNIVERSITY
    Inventors: Hideo SATO, Shoji IKEDA, Mathias BERSWEILER, Hiroaki HONJO, Kyota WATANABE, Shunsuke FUKAMI, Fumihiro MATSUKURA, Kenchi ITO, Masaaki NIWA, Tetsuo ENDOH, Hideo OHNO
  • 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
  • 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: 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
  • 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: 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
  • 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
  • Publication number: 20160247550
    Abstract: A magnetoresistive device includes a magnetic free layer having first and second surfaces, the magnetic free layer being comprised of a ferromagnetic material having a perpendicular magnetic anisotropy, a spin current generation layer contacting the first surface of the magnetic free layer, a tunnel barrier layer having one surface contacting the second surface of the magnetic free layer, a reference layer contacting another surface of the tunnel barrier layer, and a leakage field generation layer including first and second leakage field generation layers each of which is comprised of a ferromagnetic material and generates a leakage field, an in-plane component of the leakage field at an part of the magnetic free layer is formed generating a domain wall having an in-plane magnetization component in the magnetic free layer.
    Type: Application
    Filed: May 2, 2016
    Publication date: August 25, 2016
    Applicants: NEC CORPORATION, TOHOKU UNIVERSITY
    Inventors: Shunsuke FUKAMI, Michihiko YAMANOUCHI, Hideo OHNO
  • Publication number: 20160233416
    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: Application
    Filed: October 20, 2014
    Publication date: August 11, 2016
    Applicant: TOHOKU UNIVERSITY
    Inventors: Shoji IKEDA, Hideo SATO, Shunsuke FUKAMI, Michihiko YAMANOUCHI, Fumihiro MATSUKURA, Hideo OHNO, Shinya ISHIKAWA
  • Patent number: 9379312
    Abstract: A magnetoresistive effect element of the present invention includes: a domain wall motion layer, a spacer layer and a reference layer. The domain wall motion layer is made of ferromagnetic material with perpendicular magnetic anisotropy. The spacer layer is formed on the domain wall motion layer and made of non-magnetic material. The reference layer is formed on the spacer layer and made of ferromagnetic material, magnetization of the reference layer being fixed. The domain wall motion layer includes at least one domain wall, and stores data corresponding to a position of the domain wall. An anisotropy magnetic field of the domain wall motion layer is larger than a value in which the domain wall motion layer can hold the perpendicular magnetic anisotropy, and smaller than an essential value of an anisotropy magnetic field of the ferromagnetic material of the domain wall motion layer.
    Type: Grant
    Filed: December 14, 2010
    Date of Patent: June 28, 2016
    Assignee: NEC CORPORATION
    Inventors: Tadahiko Sugibayashi, Eiji Kariyada, Kaoru Mori, Norikazu Ohshima, Shunsuke Fukami, Tetsuhiro Suzuki, Hironobu Tanigawa, Sadahiko Miura, Nobuyuki Ishiwata
  • Patent number: 9202545
    Abstract: A magnetoresistance effect element including a recording layer of high thermal stability to perform perpendicular magnetic recording within a film surface, and a magnetic memory using the element. The element includes: a first ferromagnetic layer of an invariable magnetization direction; a second ferromagnetic layer of a variable magnetization direction; a first non-magnetic layer between the first and second ferromagnetic layers; current supply terminals connected to the first and second ferromagnetic layers; a non-magnetic coupling layer on a surface of the second ferromagnetic layer opposite the first non-magnetic layer; a third ferromagnetic layer of a variable magnetization direction on a surface of the non-magnetic coupling layer opposite the second ferromagnetic layer; and a second non-magnetic layer on a surface of the third ferromagnetic layer opposite the non-magnetic coupling layer.
    Type: Grant
    Filed: March 25, 2013
    Date of Patent: December 1, 2015
    Assignee: TOHOKU UNIVERSITY
    Inventors: Hideo Sato, Shunsuke Fukami, Michihiko Yamanouchi, Shoji Ikeda, Fumihiro Matsukura, Hideo Ohno
  • Publication number: 20150332818
    Abstract: A magnetic material includes a structure in which a first magnetic layer 1 and a second magnetic layer 2 are stacked such that each layer is formed at least partially in a stacking direction by substantially one atomic layer. The first magnetic layer contains Co as a principal component. The second magnetic layer includes at least Ni. The magnetic material has magnetic anisotropy in the stacking direction. Preferably, an atomic arrangement within a film surface of the first magnetic layer and the second magnetic layer has six-fold symmetry.
    Type: Application
    Filed: November 11, 2013
    Publication date: November 19, 2015
    Inventors: Shunsuke FUKAMI, Hideo SATO, Michihiko YAMANOUCHI, Shoji IKEDA, Hideo OHNO
  • Patent number: 9105831
    Abstract: Provided is a nonvolatile magnetic device that is capable of realizing low power consumption by performing writing with a voltage and is also excellent in retention characteristics. The nonvolatile magnetic device includes a nonvolatile magnetic element. The nonvolatile magnetic element includes: a first free layer made of a ferromagnetic substance; a first insulating layer made of an insulator, the first insulating layer being provided to be connected to the first free layer; a charged layer provided adjacent to the first insulating layer; a second insulating layer made of an insulator, the second insulating layer being provided adjacent to the charged layer; and an injection layer provided adjacent to the second insulating layer. The charged layer is smaller in electric resistivity than both of the first insulating layer and the second insulating layer. The injection layer is smaller in electric resistivity than the second insulating layer.
    Type: Grant
    Filed: June 13, 2012
    Date of Patent: August 11, 2015
    Assignees: NEC CORPORATION, KYOTO UNIVERSITY
    Inventors: Shunsuke Fukami, Daichi Chiba
  • Patent number: 9083336
    Abstract: A non-volatile logic operation device includes an operation unit that is connected to a first input terminal, a second input terminal, and an output terminal, includes an operation layer, a first non-magnetic layer, and a reference layer, and outputs from the output terminal a result of a logic operation on signals applied at the first input terminal and the second input terminal, and a control unit that is connected to a third input terminal, and includes a control layer. The control unit is arranged in the vicinity of the operation unit.
    Type: Grant
    Filed: January 5, 2012
    Date of Patent: July 14, 2015
    Assignee: NEC Corporation
    Inventors: Shunsuke Fukami, Nobuyuki Ishiwata
  • Publication number: 20150109853
    Abstract: A magnetoresistance effect element including a recording layer of high thermal stability to perform perpendicular magnetic recording within a film surface, and a magnetic memory using the element. The element includes: a first ferromagnetic layer of an invariable magnetization direction; a second ferromagnetic layer of a variable magnetization direction; a first non-magnetic layer between the first and second ferromagnetic layers; current supply terminals connected to the first and second ferromagnetic layers; a non-magnetic coupling layer on a surface of the second ferromagnetic layer opposite the first non-magnetic layer; a third ferromagnetic layer of a variable magnetization direction on a surface of the non-magnetic coupling layer opposite the second ferromagnetic layer; and a second non-magnetic layer on a surface of the third ferromagnetic layer opposite the non-magnetic coupling layer.
    Type: Application
    Filed: March 25, 2013
    Publication date: April 23, 2015
    Applicant: TOHOKU UNIVERSITY
    Inventors: Hideo Sato, Shunsuke Fukami, Michihiko Yamanouchi, Shoji Ikeda, Fumihiro Matsukura, Hideo Ohno
  • Patent number: 8994130
    Abstract: A magnetic memory element includes: a first magnetization free layer formed of a ferromagnetic material having perpendicular magnetic anisotropy; a second magnetization free layer provided near the first magnetization free layer and formed of a ferromagnetic material having in-plane magnetic anisotropy; a reference layer formed of a ferromagnetic material having in-plane magnetic anisotropy; and a non-magnetic layer provided between the second magnetization free layer and the reference layer. The first magnetization free layer includes: a first magnetization fixed region of which magnetization is fixed, a second magnetization fixed region of which magnetization is fixed, and a magnetization free region which is connected to the first magnetization fixed region and the second magnetization fixed region, and of which magnetization can be switched. The second magnetization free layer is included in the first magnetization free layer in a plane parallel to a substrate.
    Type: Grant
    Filed: January 28, 2010
    Date of Patent: March 31, 2015
    Assignee: NEC Corporation
    Inventors: Shunsuke Fukami, Tetsuhiro Suzuki, Kiyokazu Nagahara, Nobuyuki Ishiwata, Norikazu Ohshima
  • Patent number: 8884388
    Abstract: A magnetic memory element includes: a first magnetization free layer configured to be composed of ferromagnetic material with perpendicular magnetic anisotropy; a reference layer configured to be provided near the first magnetization free layer; a non-magnetic layer configured to be provided adjacent to the reference layer; and a step formation layer configured to be provided under the first magnetization free layer. The first magnetization free layer includes: a first magnetization fixed region of which magnetization is fixed, a second magnetization fixed region of which magnetization is fixed, and a magnetization free region configured to be connected with the first magnetization fixed region and the second magnetization fixed region. The first magnetization free layer has at least one of a step, a groove and a protrusion inside.
    Type: Grant
    Filed: March 9, 2011
    Date of Patent: November 11, 2014
    Assignee: NEC Corporation
    Inventors: Shunsuke Fukami, Kiyokazu Nagahara, Tetsuhiro Suzuki
  • Patent number: 8791534
    Abstract: In a perpendicular magnetization domain wall motion MRAM in which the magnetizations of both ends of a magnetization free layer are pinned by magnetization pinned layers, the increase of a write current due to leakage magnetic field from the magnetization pinned layer is prevented. A first displacement is present between a first boundary line and a first vertical line, where a curve portion, which crosses a first magnetization free layer, of an outer circumferential line of a first magnetization pinned layer is the first boundary line, a segment which links a center of a magnetization free region and a center of a first magnetization pinned region is a first segment, and a segment, which is a vertical line of the first segment, and which comes in contact with the first boundary line is the first vertical line.
    Type: Grant
    Filed: June 16, 2011
    Date of Patent: July 29, 2014
    Assignee: NEC Corporation
    Inventors: Shunsuke Fukami, Tetsuhiro Suzuki, Kiyokazu Nagahara, Nobuyuki Ishiwata, Norikazu Ohshima
  • Patent number: 8787076
    Abstract: A magnetic memory according to the present invention has: a first underlayer; a second underlayer so formed on the first underlayer as to be in contact with the first underlayer; and a data storage layer so formed on the second underlayer as to be in contact with the second underlayer. The data storage layer is made of a ferromagnetic material having perpendicular magnetic anisotropy. A magnetization state of the data storage layer is changed by current driven domain wall motion.
    Type: Grant
    Filed: August 13, 2009
    Date of Patent: July 22, 2014
    Assignee: NEC Corporation
    Inventors: Shunsuke Fukami, Nobuyuki Ishiwata, Tetsuhiro Suzuki, Kiyokazu Nagahara, Norikazu Ohshima