Patents by Inventor Shiho Nakamura

Shiho Nakamura 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: 7120049
    Abstract: A magnetic cell includes a first ferromagnetic layer whose magnetization is substantially fixed in a first direction; a second ferromagnetic layer whose magnetization is substantially fixed in a second direction opposite to the first direction; a third ferromagnetic layer provided between the first and the second ferromagnetic layers, a direction of magnetization of the third ferromagnetic layer being variable; a first intermediate layer provided between the first and the third ferromagnetic layers; and a second intermediate layer provided between the second and the third ferromagnetic layers. The direction of magnetization of the third ferromagnetic layer can be determined under an influence of spin-polarized electrons upon the third ferromagnetic layer by passing a current between the first and the second ferromagnetic layers.
    Type: Grant
    Filed: April 18, 2006
    Date of Patent: October 10, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shiho Nakamura, Shigeru Haneda, Yuichi Ohsawa
  • Publication number: 20060187705
    Abstract: A magnetic cell includes a first ferromagnetic layer whose magnetization is substantially fixed in a first direction; a second ferromagnetic layer whose magnetization is substantially fixed in a second direction opposite to the first direction; a third ferromagnetic layer provided between the first and the second ferromagnetic layers, a direction of magnetization of the third ferromagnetic layer being variable; a first intermediate layer provided between the first and the third ferromagnetic layers; and a second intermediate layer provided between the second and the third ferromagnetic layers. The direction of magnetization of the third ferromagnetic layer can be determined under an influence of spin-polarized electrons upon the third ferromagnetic layer by passing a current between the first and the second ferromagnetic layers.
    Type: Application
    Filed: April 18, 2006
    Publication date: August 24, 2006
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Shiho Nakamura, Shigeru Haneda, Yuichi Ohsawa
  • Patent number: 7075755
    Abstract: A magneto-resistance effect element of the present invention allows detection of a micro-bit signal with a high sensitivity. The magneto-resistance effect element is provided with a first magnetic substance layer, a spacer layer stacked on the first magnetic substance layer, a second magnetic substance layer stacked on the spacer, an insulating layer positioned adjacent to a stacked structure comprising the first magnetic substance layer, the spacer layer and the second magnetic substance layer, a gate electrode positioned adjacent to the insulating layer, and a magnetism sensitive region controlled by a voltage applied to the gate electrode.
    Type: Grant
    Filed: September 29, 2003
    Date of Patent: July 11, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shigeru Haneda, Yuichi Osawa, Shiho Nakamura
  • Publication number: 20060132990
    Abstract: A magnetic recording element includes a first fixed layer having a first and second face and having a magnetization direction fixed in a direction penetrating the first and second face. A free layer has a third and fourth face, a magnetization easy and hard axis both extending along the third or fourth face, and a magnetization direction which changes according to a direction of a current flowing through the first and fourth face with a magnetic field applied in a fixed direction or according to a direction of a magnetic field applied to the free layer with a current flowing through the first and fourth face in a fixed direction. A nonmagnetic first intermediate layer is provided between the second and third face. A magnetic field generating layer applies a magnetic field smaller than the anisotropy field of the free layer to the free layer along the magnetization hard axis.
    Type: Application
    Filed: December 19, 2005
    Publication date: June 22, 2006
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hirofumi Morise, Shiho Nakamura, Shigeru Haneda, Takahiro Hirai
  • Publication number: 20060120126
    Abstract: A magnetic cell comprises: a first ferromagnetic layer whose magnetization is substantially fixed in a first direction; a second ferromagnetic layer whose magnetization is substantially fixed in a second direction opposite to the first direction; a third ferromagnetic layer provided between the first and the second ferromagnetic layers, a direction of magnetization of the third ferromagnetic layer being variable; a first intermediate layer provided between the first and the third ferromagnetic layers; and a second intermediate layer provided between the second and the third ferromagnetic layers. The direction of magnetization of the third ferromagnetic layer can be determined under an influence of spin-polarized electrons upon the third ferromagnetic layer by passing a current between the first and the second ferromagnetic layers.
    Type: Application
    Filed: January 10, 2006
    Publication date: June 8, 2006
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Shiho Nakamura, Shigeru Haneda, Yuichi Ohsawa
  • Patent number: 7042762
    Abstract: A magnetic element, including a first magnetic reference part (a) including a first ferromagnetic substance pinned in magnetization (M1) substantially in a first direction, a second magnetic reference part (E) including a second ferromagnetic substance pinned in magnetization (M3) substantially in a second direction, and a magnetic recording part (C) provided between the first and second magnetic reference parts. The magnetic recording part includes a third ferromagnetic substance. A spin transfer intermediate part (B) is provided between the first magnetic reference part and the magnetic recording part. An intermediate part (D) is provided between the second magnetic reference part and the magnetic recording part. A magnetization (M2) of the third ferromagnetic substance can be directed in a direction parallel or anti-parallel to the first direction by passing a writing current between the first magnetic reference part and the magnetic recording part.
    Type: Grant
    Filed: May 2, 2005
    Date of Patent: May 9, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shiho Nakamura, Shigeru Haneda, Hiroaki Yoda
  • Patent number: 7042758
    Abstract: It is possible to provide a magnetic cell having a high developing rate of MR characteristics and a reduced fluctuation without causing element falling-down and a magnetic memory having the same.
    Type: Grant
    Filed: September 20, 2004
    Date of Patent: May 9, 2006
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shigeru Haneda, Shiho Nakamura, Yuuichi Oosawa
  • Publication number: 20060060989
    Abstract: A magnetic recording element, in which a spin-polarized electron is injected, has a layer whose magnetization direction is changed by the spin-polarized electron in accordance with a flow direction of the spin-polarized electron and records data in accordance with the magnetization direction. The magnetic recording element includes a free layer whose magnetization direction is changed by an action of a spin-polarized electron and has a spin polarization Pf. A pinned layer whose magnetization direction is fixed has a spin polarization Pp larger than the spin polarization Pf. An intermediate layer is interposed between the pinned layer and the free layer and consisting essentially of a nonmagnetic material.
    Type: Application
    Filed: June 8, 2005
    Publication date: March 23, 2006
    Inventors: Hirofumi Morise, Shiho Nakamura, Shigeru Haneda
  • Publication number: 20060060901
    Abstract: A magnetic recording element includes a fixed layer having first and second surfacesm, a recording layer having third and fourth surfaces and being essentially made of a ferromagnetic material having first and second atomic potentials for the majority-spin band electrons and the minority-spin band electrons, a spacer layer being arranged between the fixed and recording layers and being in contact with the second and third surfaces, a cap layer having fifth and sixth surfaces, being essentially made of a nonmagnetic material having a third atomic potential less than an intermediate value between the first and second atomic potentials, and having a thickness of not more than 3 nm, the fifth surface being in contact with the fourth surface, and a reflecting layer being in contact with the sixth surface and being essentially made of a nonmagnetic material having a forth atomic potential different from the third atomic potential.
    Type: Application
    Filed: April 29, 2005
    Publication date: March 23, 2006
    Inventors: Shiho Nakamura, Shigeru Haneda, Hirofumi Morise
  • Publication number: 20060007730
    Abstract: A magnetic cell comprises: a first ferromagnetic layer whose magnetization is substantially fixed in a first direction; a second ferromagnetic layer whose magnetization is substantially fixed in a second direction opposite to the first direction; a third ferromagnetic layer provided between the first and the second ferromagnetic layers, a direction of magnetization of the third ferromagnetic layer being variable; a first intermediate layer provided between the first and the third ferromagnetic layers; and a second intermediate layer provided between the second and the third ferromagnetic layers. The direction of magnetization of the third ferromagnetic layer can be determined under an influence of spin-polarized electrons upon the third ferromagnetic layer by passing a current between the first and the second ferromagnetic layers.
    Type: Application
    Filed: September 16, 2005
    Publication date: January 12, 2006
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Shiho Nakamura, Shigeru Haneda, Yuichi Ohsawa
  • Publication number: 20060002185
    Abstract: A magnetic cell comprises: a first ferromagnetic layer whose magnetization is substantially fixed in a first direction; a second ferromagnetic layer whose magnetization is substantially fixed in a second direction opposite to the first direction; a third ferromagnetic layer provided between the first and the second ferromagnetic layers, a direction of magnetization of the third ferromagnetic layer being variable; a first intermediate layer provided between the first and the third ferromagnetic layers; and a second intermediate layer provided between the second and the third ferromagnetic layers. The direction of magnetization of the third ferromagnetic layer can be determined under an influence of spin-polarized electrons upon the third ferromagnetic layer by passing a current between the first and the second ferromagnetic layers.
    Type: Application
    Filed: August 30, 2005
    Publication date: January 5, 2006
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Shiho Nakamura, Shigeru Haneda, Yuichi Ohsawa
  • Patent number: 6956766
    Abstract: A magnetic cell comprises: a first ferromagnetic layer whose magnetization is substantially fixed in a first direction; a second ferromagnetic layer whose magnetization is substantially fixed in a second direction opposite to the first direction; a third ferromagnetic layer provided between the first and the second ferromagnetic layers, a direction of magnetization of the third ferromagnetic layer being variable; a first intermediate layer provided between the first and the third ferromagnetic layers; and a second intermediate layer provided between the second and the third ferromagnetic layers. The direction of magnetization of the third ferromagnetic layer can be determined under an influence of spin-polarized electrons upon the third ferromagnetic layer by passing a current between the first and the second ferromagnetic layers.
    Type: Grant
    Filed: November 26, 2003
    Date of Patent: October 18, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shiho Nakamura, Shigeru Haneda, Yuichi Ohsawa
  • Publication number: 20050219767
    Abstract: A magneto-resistive element comprising a free layer having two ferromagnetic layers having a nonmagnetic layer interposed therebetween are coupled with each other in an anti-ferromagnetic manner, a difference between an absolute value of a total of magnetizations of at least one ferromagnetic layer in which the magnetization direction is a first direction and an absolute value of a total of magnetizations of at least one ferromagnetic layer in which the magnetization direction is a second direction which is opposite to the first direction is equal to or smaller than 5×10?15 emu, and planes parallel to a substrate of the ferromagnetic layers are smaller as the planes are distant from the substrate.
    Type: Application
    Filed: March 24, 2005
    Publication date: October 6, 2005
    Inventors: Shiho Nakamura, Shigeru Haneda
  • Publication number: 20050219768
    Abstract: A magneto-resistance effect element can obtain a high output and makes it possible to stabilize magnetization in a magnetization free layer therein even if a sense current is caused to flow. The magneto-resistance effect element is provided with a magnetization free layer whose magnetization direction is variable, a magnetization pinned layer whose magnetization direction is pinned, and an intermediate layer provided between the magnetization free layer and the magnetization pinned layer, where when no external magnetic field is present and no current flows, the magnetization direction in the magnetization free layer is anti-parallel to the magnetization direction pinned in the magnetization pinned layer, an easy axis of magnetization in the magnetization free layer is parallel to the magnetization direction pinned in the magnetization pinned layer, and a sense current flows from the magnetization free layer to the magnetization pinned layer.
    Type: Application
    Filed: March 28, 2005
    Publication date: October 6, 2005
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Shiho Nakamura, Shigeru Haneda, Hirofumi Morise
  • Publication number: 20050190594
    Abstract: A magnetic element comprises a first magnetic reference part (A) including a first ferromagnetic substance pinned in magnetization (M1) substantially in a first direction, a second magnetic reference part (E) including a second ferromagnetic substance pinned in magnetization (M3) substantially in a second direction, and a magnetic recording part (C) provided between the first and second magnetic reference parts. The magnetic recording part includes a third ferromagnetic substance. A spin transfer intermediate part (B) is provided between the first magnetic reference part and the magnetic recording part. An intermediate part (D) is provided between the second magnetic reference part and the magnetic recording part. A magnetization (M2) of the third ferromagnetic substance can be directed in a direction parallel or anti-parallel to the first direction by passing a writing current between the first magnetic reference part and the magnetic recording part.
    Type: Application
    Filed: May 2, 2005
    Publication date: September 1, 2005
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Shiho Nakamura, Shigeru Haneda, Hiroaki Yoda
  • Patent number: 6914807
    Abstract: A magnetic logic element comprises a magnetic logic element cell having; a first and second magnetic parts; a MR intermediate part provided between the first and second magnetic parts. The magnetic logic element further includes a magnetization controlling part that controls a relation of directions of magnetizations of the first and second magnetic parts in accordance with a combination of a first binary input data and a second binary input data. A binary output data can be read by detecting a magnetoresistance effect of the first and second magnetic parts through the MR intermediate part.
    Type: Grant
    Filed: March 31, 2003
    Date of Patent: July 5, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shiho Nakamura, Shigeru Haneda
  • Patent number: 6906949
    Abstract: A magnetic element comprises a first magnetic reference part (A) including a first ferromagnetic substance pinned in magnetization (M1) substantially in a first direction, a second magnetic reference part (E) including a second ferromagnetic substance pinned in magnetization (M3) substantially in a second direction, and a magnetic recording part (C) provided between the first and second magnetic reference parts. The magnetic recording part includes a third ferromagnetic substance. A spin transfer intermediate part (B) is provided between the first magnetic reference part and the magnetic recording part. An intermediate part (D) is provided between the second magnetic reference part and the magnetic recording part. A magnetization (M2) of the third ferromagnetic substance can be directed in a direction parallel or anti-parallel to the first direction by passing a writing current between the first magnetic reference part and the magnetic recording part.
    Type: Grant
    Filed: March 31, 2003
    Date of Patent: June 14, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shiho Nakamura, Shigeru Haneda, Hiroaki Yoda
  • Publication number: 20050105325
    Abstract: It is possible to provide a magnetic cell having a high developing rate of MR characteristics and a reduced fluctuation without causing element falling-down and a magnetic memory having the same.
    Type: Application
    Filed: September 20, 2004
    Publication date: May 19, 2005
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Shigeru Haneda, Shiho Nakamura, Yuuichi Oosawa
  • Publication number: 20050099724
    Abstract: A magnetic device comprises first through third ferromagnetic layers, first and second intermediate layers and a couple of electrodes. The first ferromagnetic layer includes magnetic layers and one or more nonmagnetic layers which are alternately stacked, at least one layer of the magnetic layers has magnetization substantially fixed to a first direction, and two or more layers of the magnetic layers are ferromagnetically coupled via the nonmagnetic layers while having easy axes of magnetization parallel to a film plane. The second ferromagnetic layer has magnetization substantially fixed to a second direction. The third ferromagnetic layer is provided between the first ferromagnetic layer and the second ferromagnetic layer. The third ferromagnetic layer has a variable direction of magnetization. The first and second intermediate layers are provided between the ferromagnetic layers.
    Type: Application
    Filed: September 30, 2004
    Publication date: May 12, 2005
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Shiho Nakamura, Shigeru Haneda
  • Publication number: 20040165425
    Abstract: A magnetic cell comprises: a first ferromagnetic layer whose magnetization is substantially fixed in a first direction; a second ferromagnetic layer whose magnetization is substantially fixed in a second direction opposite to the first direction; a third ferromagnetic layer provided between the first and the second ferromagnetic layers, a direction of magnetization of the third ferromagnetic layer being variable; a first intermediate layer provided between the first and the third ferromagnetic layers; and a second intermediate layer provided between the second and the third ferromagnetic layers. The direction of magnetization of the third ferromagnetic layer can be determined under an influence of spin-polarized electrons upon the third ferromagnetic layer by passing a current between the first and the second ferromagnetic layers.
    Type: Application
    Filed: November 26, 2003
    Publication date: August 26, 2004
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Shiho Nakamura, Shigeru Haneda, Yuichi Ohsawa