Patents by Inventor Tomoaki Inokuchi

Tomoaki Inokuchi 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: 7511991
    Abstract: A spin-injection magnetic random access memory according to an embodiment of the invention includes a magnetoresistive element having a magnetic fixed layer whose magnetization direction is fixed, a magnetic recording layer whose magnetization direction can be changed by injecting spin-polarized electrons, and a tunnel barrier layer provided between the magnetic fixed layer and the magnetic recording layer, a bit line which passes spin-injection current through the magnetoresistive element, the spin-injection current being used for generation of the spin-polarized electrons, a writing word line through which assist current is passed, the assist current being used for the generation of an assist magnetic field in a magnetization easy-axis direction of the magnetoresistive element, and a driver/sinker which determines a direction of the spin-injection current and a direction of the assist current.
    Type: Grant
    Filed: May 18, 2007
    Date of Patent: March 31, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki Saito, Hideyuki Sugiyama, Tomoaki Inokuchi, Yoshihisa Iwata
  • Publication number: 20090059659
    Abstract: A spin transistor includes a first ferromagnetic layer provided on a substrate and having an invariable magnetization direction, a second ferromagnetic layer provided on the substrate apart from the first ferromagnetic layer in a first direction, and having a variable magnetization direction, a plurality of projecting semiconductor layers provided on the substrate to extend in the first direction, and sandwiched between the first ferromagnetic layer and the second ferromagnetic layer, a plurality of channel regions respectively provided in the projecting semiconductor layers, and a gate electrode provided on the channel regions.
    Type: Application
    Filed: August 28, 2008
    Publication date: March 5, 2009
    Inventors: Tomoaki INOKUCHI, Mizue Ishikawa, Hideyuki Sugiyama, Yoshiaki Saito
  • Publication number: 20090057654
    Abstract: A spin FET of an aspect of the present invention includes source/drain regions, a channel region between the source/drain regions, and a gate electrode above the channel region. Each of the source/drain regions includes a stack structure which is comprised of a low work function material and a ferromagnet. The low work function material is a non-oxide which is comprised of one of Mg, K, Ca and Sc, or an alloy which includes the non-oxide of 50 at % or more.
    Type: Application
    Filed: August 25, 2008
    Publication date: March 5, 2009
    Inventors: Yoshiaki SAITO, Hideyuki Sugiyama, Tomoaki Inokuchi, Mizue Ishikawa
  • Publication number: 20090050948
    Abstract: A spin MOS field effect transistor includes a source electrode and a drain electrode each having a structure obtained by stacking an impurity diffusion layer, a (001)-oriented MgO layer and a Heusler alloy. The impurity diffusion layer is formed in a surface region of a semiconductor layer. The (001)-oriented MgO layer is formed on the impurity diffusion layer. The Heusler alloy is formed on the MgO layer.
    Type: Application
    Filed: August 20, 2008
    Publication date: February 26, 2009
    Inventors: Mizue ISHIKAWA, Yoshiaki Saito, Hideyuki Sugiyama, Tomoaki Inokuchi
  • Publication number: 20080247223
    Abstract: A spin-injection magnetic random access memory of an aspect of the present invention includes a magnetoresistive element, a unit which writes data into the magnetoresistive element by use of spin-polarized electrons generated by a spin-injection current and which applies, to the magnetoresistive element, a magnetic field of a direction of a hard magnetization of the magnetoresistive element during the writing.
    Type: Application
    Filed: June 4, 2008
    Publication date: October 9, 2008
    Inventors: Tomoaki INOKUCHI, Yoshiaki Saito, Hideyuki Sugiyama
  • Publication number: 20080239930
    Abstract: A spin FET includes a first ferromagnetic film disposed on a first source/drain area, a direction of magnetization thereof being fixed in an upward direction or a downward direction perpendicular to a film surface, a second ferromagnetic film disposed on a second source/drain area, a direction of magnetization thereof being changed in the upward direction or the downward direction, an anti-ferromagnetic ferroelectric film disposed on the second ferromagnetic film, and a tunnel barrier film disposed at least between the first source/drain area and the first ferromagnetic film or between the second source/drain and the second ferromagnetic film. Resistance of the anti-ferromagnetic ferroelectric film is larger than ON resistance when the first and second source/drain areas conduct electricity through the channel area.
    Type: Application
    Filed: February 11, 2008
    Publication date: October 2, 2008
    Inventors: Yoshiaki SAITO, Hideyuki SUGIYAMA, Tomoaki INOKUCHI
  • Patent number: 7394684
    Abstract: A spin-injection magnetic random access memory of an aspect of the present invention includes a magnetoresistive element, a unit which writes data into the magnetoresistive element by use of spin-polarized electrons generated by a spin-injection current and which applies, to the magnetoresistive element, a magnetic field of a direction of a hard magnetization of the magnetoresistive element during the writing.
    Type: Grant
    Filed: March 13, 2006
    Date of Patent: July 1, 2008
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomoaki Inokuchi, Yoshiaki Saito, Hideyuki Sugiyama
  • Publication number: 20080062580
    Abstract: A spin memory includes a magneto-resistance element having a first ferromagnetic layer in which a magnetization direction is pinned, a second ferromagnetic layer in which a magnetization direction changes, and a first nonmagnetic layer between the first and second ferromagnetic layers, a lower electrode and an upper electrode extending in a direction between 45 degrees and 90 degrees relative to an axis of hard magnetization of the second ferromagnetic layer, and sandwiching the magneto-resistance element at one end in a longitudinal direction, a switching element connected to another end in a longitudinal direction of the lower electrode, and a bit line connected to another end in a longitudinal direction of the upper electrode, wherein writing is carried out by supplying spin-polarized electrons to the second ferromagnetic layer and applying a magnetic field from the lower electrode and the upper electrode to the second ferromagnetic layer.
    Type: Application
    Filed: August 28, 2007
    Publication date: March 13, 2008
    Inventors: Tomoaki INOKUCHI, Yoshiaki Saito, Hideyuki Sugiyama
  • Publication number: 20080061332
    Abstract: A spin MOSFET includes: a semiconductor substrate; a first magnetic film formed on the semiconductor substrate and including a first ferromagnetic layer, a magnetization direction of the first ferromagnetic layer being pinned; a second magnetic film formed on the semiconductor substrate to separate from the first magnetic film and including a magnetization free layer, a first nonmagnetic layer being a tunnel insulator and provided on the magnetization free layer, and a magnetization pinned layer provided on the first nonmagnetic layer, a magnetization direction of the magnetization free layer being changeable and a magnetization direction of the magnetization pinned layer being fixed; a gate insulating film provided at least on the semiconductor substrate between the first magnetic film and the second magnetic film; and a gate electrode formed on the gate insulating film.
    Type: Application
    Filed: June 29, 2007
    Publication date: March 13, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yoshiaki Saito, Hideyuki Sugiyama, Tomoaki Inokuchi
  • Publication number: 20070253120
    Abstract: It is possible to provide a magnetoresistive effect element which has thermal stability even if it is made fine and in which the magnetization in the magnetic recording layer can be inverted at a low current density. A magnetoresistive effect element includes: a magnetization pinned layer having a magnetization pinned in a direction; a magnetization free layer of which magnetization direction is changeable by injecting spin-polarized electrons into the magnetization free layer; a tunnel barrier layer provided between the magnetization pinned layer and the magnetization free layer; a first antiferromagnetic layer provided on the opposite side of the magnetization pinned layer from the tunnel barrier layer; and a second antiferromagnetic layer which is provided on the opposite side of the magnetization free layer from the tunnel barrier layer and which is thinner in thickness than the first antiferromagnetic layer.
    Type: Application
    Filed: April 19, 2007
    Publication date: November 1, 2007
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yoshiaki Saito, Hideyuki Sugiyama, Tomoaki Inokuchi
  • Publication number: 20070223269
    Abstract: A spin-injection magnetic random access memory according to an embodiment of the invention includes a magnetoresistive element having a magnetic fixed layer whose magnetization direction is fixed, a magnetic recording layer whose magnetization direction can be changed by injecting spin-polarized electrons, and a tunnel barrier layer provided between the magnetic fixed layer and the magnetic recording layer, a bit line which passes spin-injection current through the magnetoresistive element, the spin-injection current being used for generation of the spin-polarized electrons, a writing word line through which assist current is passed, the assist current being used for the generation of an assist magnetic field in a magnetization easy-axis direction of the magnetoresistive element, and a driver/sinker which determines a direction of the spin-injection current and a direction of the assist current.
    Type: Application
    Filed: May 18, 2007
    Publication date: September 27, 2007
    Inventors: Yoshiaki SAITO, Hideyuki Sugiyama, Tomoaki Inokuchi, Yoshihisa Iwata
  • Patent number: 7266012
    Abstract: It is made possible to provide a highly reliable magnetoresistive effect element and magnetic memory that operate with low power consumption and low current writing. The magnetoresistive effect element includes: a magnetization free layer including at least two magnetic layers subject to antiferromagnetic coupling and a non-magnetic layer provided between the magnetic layers; a tunnel barrier layer provided on one surface of the magnetization free layer; a first magnetization pinned layer provided on an opposite surface of the tunnel barrier layer from the magnetization free layer; a non-magnetic metal layer provided on an opposite surface of the magnetization free layer from the tunnel barrier layer; and a second magnetization pinned layer provided on an opposite surface of the non-magnetic metal layer from the magnetization free layer. The first and second magnetization pinned layers are substantially the same in magnetization direction. The non-magnetic metal layer includes Cu, Ag, Au, or an alloy of them.
    Type: Grant
    Filed: March 13, 2006
    Date of Patent: September 4, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki Saito, Hideyuki Sugiyama, Tomoaki Inokuchi
  • Publication number: 20070177421
    Abstract: It is made possible to cause spin inversion at a low current density which does not cause element destruction and to conduct writing with a small current. A magnetoresistance effect element includes: a magnetization pinned layer in which magnetization direction is pinned; a magnetic recording layer in which magnetization direction is changeable, the magnetization direction in the magnetization pinned layer forming an angle which is greater than 0 degree and less than 180 degrees with a magnetization direction in the magnetic recording layer, and the magnetization direction in the magnetic recording layer being inverted by injecting spin-polarized electrons into the magnetic recording layer; and a non-magnetic metal layer provided between the magnetization pinned layer and the magnetic recording layer.
    Type: Application
    Filed: December 11, 2006
    Publication date: August 2, 2007
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hideyuki Sugiyama, Yoshiaki Saito, Tomoaki Inokuchi
  • Patent number: 7248497
    Abstract: An spin-injection FET includes a first ferromagnetic body whose magnetization direction is fixed, a second ferromagnetic body whose magnetization direction is changed by spin-injection current, a gate electrode which is formed on a channel between the first and second ferromagnetic bodies, a first driver/sinker which controls a direction of the spin-injection current to determine the magnetization direction of the second ferromagnetic body, the spin-injection current being passed through the channel, a wiring through which assist current is passed, the assist current generating a magnetic field in a magnetization easy axis direction of the second ferromagnetic body, and a second driver/sinker which controls the direction of the assist current passed through the conductive line.
    Type: Grant
    Filed: January 23, 2007
    Date of Patent: July 24, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki Saito, Hideyuki Sugiyama, Tomoaki Inokuchi
  • Publication number: 20070164336
    Abstract: A spin FET according to an example of the present invention includes a magnetic pinned layer whose magnetization direction is fixed, a magnetic free layer whose magnetization direction is changed, a channel between the magnetic pinned layer and the magnetic free layer, a gate electrode provided on the channel via a gate insulation layer, and a multiferroric layer which is provided on the magnetic free layer, and whose magnetization direction is changed by an electric field.
    Type: Application
    Filed: December 13, 2006
    Publication date: July 19, 2007
    Inventors: Yoshiaki Saito, Hideyuki Sugiyama, Tomoaki Inokuchi
  • Patent number: 7239541
    Abstract: A spin-injection magnetic random access memory according to an embodiment of the invention includes a magnetoresistive element having a magnetic fixed layer whose magnetization direction is fixed, a magnetic recording layer whose magnetization direction can be changed by injecting spin-polarized electrons, and a tunnel barrier layer provided between the magnetic fixed layer and the magnetic recording layer, a bit line which passes spin-injection current through the magnetoresistive element, the spin-injection current being used for generation of the spin-polarized electrons, a writing word line through which assist current is passed, the assist current being used for the generation of an assist magnetic field in a magnetization easy-axis direction of the magnetoresistive element, and a driver/sinker which determines a direction of the spin-injection current and a direction of the assist current.
    Type: Grant
    Filed: October 5, 2005
    Date of Patent: July 3, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki Saito, Hideyuki Sugiyama, Tomoaki Inokuchi, Yoshihisa Iwata
  • Publication number: 20070115716
    Abstract: An spin-injection FET according to an embodiment of the invention includes a first ferromagnetic body whose magnetization direction is fixed, a second ferromagnetic body whose magnetization direction is changed by spin-injection current, a gate electrode which is formed on a channel between the first and second ferromagnetic bodies, a first driver/sinker which controls a direction of the spin-injection current to determine the magnetization direction of the second ferromagnetic body, the spin-injection current being passed through the channel, a wiring through which assist current is passed, the assist current generating a magnetic field in a magnetization easy axis direction of the second ferromagnetic body, and a second driver/sinker which controls the direction of the assist current passed through the conductive line.
    Type: Application
    Filed: January 23, 2007
    Publication date: May 24, 2007
    Inventors: Yoshiaki SAITO, Hideyuki Sugiyama, Tomoaki Inokuchi
  • Publication number: 20070097736
    Abstract: A spin-injection magnetic random access memory of an aspect of the present invention includes a magnetoresistive element, a unit which writes data into the magnetoresistive element by use of spin-polarized electrons generated by a spin-injection current and which applies, to the magnetoresistive element, a magnetic field of a direction of a hard magnetization of the magnetoresistive element during the writing.
    Type: Application
    Filed: March 13, 2006
    Publication date: May 3, 2007
    Inventors: Tomoaki Inokuchi, Yoshiaki Saito, Hideyuki Sugiyama
  • Patent number: 7200037
    Abstract: An spin-injection FET includes a first ferromagnetic body whose magnetization direction is fixed, a second ferromagnetic body whose magnetization direction is changed by spin-injection current, a gate electrode which is formed on a channel between the first and second ferromagnetic bodies, a first driver/sinker which controls a direction of the spin-injection current to determine the magnetization direction of the second ferromagnetic body, the spin-injection current being passed through the channel, a wiring through which assist current is passed, the assist current generating a magnetic field in a magnetization easy axis direction of the second ferromagnetic body, and a second driver/sinker which controls the direction of the assist current passed through the conductive line.
    Type: Grant
    Filed: October 21, 2005
    Date of Patent: April 3, 2007
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiaki Saito, Hideyuki Sugiyama, Tomoaki Inokuchi
  • Publication number: 20070019463
    Abstract: It is made possible to provide a highly reliable magnetoresistive effect element and magnetic memory that operate with low power consumption and low current writing. The magnetoresistive effect element includes: a magnetization free layer including at least two magnetic layers subject to antiferromagnetic coupling and a non-magnetic layer provided between the magnetic layers; a tunnel barrier layer provided on one surface of the magnetization free layer; a first magnetization pinned layer provided on an opposite surface of the tunnel barrier layer from the magnetization free layer; a non-magnetic metal layer provided on an opposite surface of the magnetization free layer from the tunnel barrier layer; and a second magnetization pinned layer provided on an opposite surface of the non-magnetic metal layer from the magnetization free layer. The first and second magnetization pinned layers are substantially the same in magnetization direction. The non-magnetic metal layer includes Cu, Ag, Au, or an alloy of them.
    Type: Application
    Filed: March 13, 2006
    Publication date: January 25, 2007
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yoshiaki Saito, Hideyuki Sugiyama, Tomoaki Inokuchi