Patents by Inventor Satoshi Yanagi

Satoshi Yanagi 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: 7889543
    Abstract: A magnetic memory element is provided with first and second ferromagnetic fixed layers, a ferromagnetic memory layer, nonmagnetic first and second intermediate layers. The memory layer is disposed between the first and second fixed layers, and has a variable magnetization direction. In order to cancel asymmetry of a write-in current of the element, the element is provided so that the memory layer receives a larger perpendicular stray field from the first fixed layer than from the second fixed layer, and then a magnetization direction of a portion of the memory layer being nearest to the first intermediate layer and the magnetization direction of the first fixed layer are antiparallel to each other whenever a magnetization direction of a portion of the memory layer being nearest to the second intermediate layer and the magnetization direction of the second fixed layer are parallel to each other, and vice versa.
    Type: Grant
    Filed: February 20, 2009
    Date of Patent: February 15, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hirofumi Morise, Shiho Nakamura, Yuichi Ohsawa, Satoshi Yanagi, Daisuke Saida
  • Patent number: 7714399
    Abstract: A magnetic memory element includes a laminated construction of an electrode, a first pinned layer, a first intermediate layer, a first memory layer, a second intermediate layer, a second memory layer, a third intermediate layer, a second pinned layer and electrode. The magnetization direction of the first memory layer takes a first and a second directions and that of the second memory layer takes a third and a fourth directions corresponding to a value and polarity of a current between the electrodes. In response to the current, the second intermediate layer has an electric resistance higher than the first intermediate layer and than the third intermediate layer.
    Type: Grant
    Filed: September 21, 2007
    Date of Patent: May 11, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hirofumi Morise, Shiho Nakamura, Satoshi Yanagi
  • Publication number: 20090213638
    Abstract: A magnetic memory element is provided with first and second ferromagnetic fixed layers, a ferromagnetic memory layer, nonmagnetic first and second intermediate layers. The memory layer is disposed between the first and second fixed layers, and has a variable magnetization direction. In order to cancel asymmetry of a write-in current of the element, the element is provided so that the memory layer receives a larger perpendicular stray field from the first fixed layer than from the second fixed layer, and then a magnetization direction of a portion of the memory layer being nearest to the first intermediate layer and the magnetization direction of the first fixed layer are antiparallel to each other whenever a magnetization direction of a portion of the memory layer being nearest to the second intermediate layer and the magnetization direction of the second fixed layer are parallel to each other, and vice versa.
    Type: Application
    Filed: February 20, 2009
    Publication date: August 27, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hirofumi Morise, Shiho Nakamura, Yuichi Ohsawa, Satoshi Yanagi, Daisuke Saida
  • Publication number: 20090207724
    Abstract: A magnetic memory is provided with a memory cell. The memory cell includes a magnetic recording element, an interconnection to generate a radio-frequency current-induced magnetic field and a ground line. The magnetic recording element is provided with a first magnetic layer whose magnetization direction is substantially fixed, a magnetic recording layer whose magnetization direction is substantially reversed by spin-polarized electrons passing through the magnetic recording layer and a first nonmagnetic layer provided between the first magnetic layer and the magnetic recording layer. The interconnection is provided above the magnetic recording element to generate a radio-frequency current-induced magnetic field acting in a direction substantially perpendicular to a magnetization easy axis of the magnetic recording layer. The ground line is provided on a side opposite to the magnetic recording element with respect to the interconnection.
    Type: Application
    Filed: February 10, 2009
    Publication date: August 20, 2009
    Inventors: Satoshi Yanagi, Yuichi Ohsawa, Shiho Nakamura, Daisuke Saida, Hirofumi Morise
  • Publication number: 20090098412
    Abstract: A magnetic recording element includes a multilayer having a surface and a pair of electrodes. The multilayer has a first magnetic fixed layer whose magnetization is substantially fixed in a first direction substantially perpendicular to the surface. The multilayer also has a second magnetic fixed layer whose magnetization is substantially fixed in a second direction opposite to the first direction substantially perpendicular to the surface. A third magnetic layer is provided between the first and second magnetic layers. The direction of magnetization of the third ferromagnetic layer is variable. A first intermediate layer is provided between the first and the third magnetic layers. A second intermediate layer is provided between the second and the third magnetic layers. The pair of electrodes is capable of supplying an electric current flowing in a direction substantially perpendicular to the surface to the multilayer.
    Type: Application
    Filed: October 3, 2008
    Publication date: April 16, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yuichi Ohsawa, Shiho Nakamura, Hirofumi Morise, Satoshi Yanagi, Daisuke Saida
  • Publication number: 20090052237
    Abstract: A magnetic memory element includes a laminated construction of a first electrode, a first pinned layer, a first intermediate layer, a memory layer, a second intermediate layer, a second pinned layer and a second electrode, and a third electrode coupled to the first intermediate layer and not directly coupled to the memory layer. The magnetization directions of the first pinned layer, the second pinned layer, and the memory layer are parallel or antiparallel to each other. The magnetization direction of the memory layer takes a first direction when the current is passed with a first polarity so that the current flowing through the first pinned layer exceeds a first threshold. The magnetization direction of the memory layer takes a second direction when the current is passed with a second polarity so that the current flowing through the first pinned layer exceeds a second threshold.
    Type: Application
    Filed: April 22, 2008
    Publication date: February 26, 2009
    Inventors: Hirofumi Morise, Shiho Nakamura, Satoshi Yanagi, Yuichi Ohsawa, Daisuke Saida
  • Publication number: 20090015958
    Abstract: A magnetic recording device includes: a laminated body including: a first ferromagnetic layer with a magnetization substantially fixed in a first direction; a second ferromagnetic layer with a variable magnetization direction; a first nonmagnetic layer disposed between the first ferromagnetic layer and the second ferromagnetic layer; and a third ferromagnetic layer with a variable magnetization direction. The magnetization direction of the second ferromagnetic layer is determinable in response to the orientation of a current, by allowing electrons spin-polarized by passing a current in a direction generally perpendicular to the film plane of the layers of the laminated body to act on the second ferromagnetic layer, and by allowing a magnetic field generated by precession of the magnetization of the third ferromagnetic layer to act on the second ferromagnetic layer.
    Type: Application
    Filed: July 11, 2008
    Publication date: January 15, 2009
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Shiho Nakamura, Hirofumi Morise, Satoshi Yanagi, Daisuke Saida, Akira Kikitsu
  • Publication number: 20080197431
    Abstract: A magnetic memory element includes a laminated construction of an electrode, a first pinned layer, a first intermediate layer, a first memory layer, a second intermediate layer, a second memory layer, a third intermediate layer, a second pinned layer and electrode. The magnetization direction of the first memory layer takes a first and a second directions and that of the second memory layer takes a third and a fourth directions corresponding to a value and polarity of a current between the electrodes. In response to the current, the second intermediate layer has an electric resistance higher than the first intermediate layer and than the third intermediate layer.
    Type: Application
    Filed: September 21, 2007
    Publication date: August 21, 2008
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Hirofumi Morise, Shiho Nakamura, Satoshi Yanagi