Patents by Inventor Daisuke Saida

Daisuke Saida 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: 20140085969
    Abstract: According to one embodiment, a nonvolatile memory device includes a memory unit and a control unit. The memory unit includes a magnetic memory element which includes: a first and second ferromagnetic layers; and a first nonmagnetic layer provided between the first and the second ferromagnetic layers. The memory unit includes a magnetic field application unit configured to apply a magnetic field to the second ferromagnetic layer, the magnetic field having a component in a first in-plane direction perpendicular to a stacking direction. The control unit is electrically connected to the magnetic memory element, and is configured to implement a setting operation of changing a voltage between the first and the second ferromagnetic layers from a first set voltage to a second set voltage. The magnetic field applied by the magnetic field application unit satisfies the condition of ? ? ? H > ( H u + H dx ) ? ( H u + H dx - H ext ) ( H u + H dx + H ext ) .
    Type: Application
    Filed: March 18, 2013
    Publication date: March 27, 2014
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Daisuke SAIDA, Naoharu Shimomura, Minoru Amano, Eiji Kitagawa, Yoshishige Suzuki
  • Publication number: 20140085968
    Abstract: According to one embodiment, a nonvolatile memory device includes: a magnetic memory element and a control unit. The magnetic memory element includes a stacked body, and a first and a second stacked units. The first stacked unit includes a first and second ferromagnetic layers and a first nonmagnetic layer provided between the first and the second ferromagnetic layers. The second stacked unit includes a third ferromagnetic layer and a nonmagnetic tunneling barrier layer stacked with the third ferromagnetic layer. The control unit is configured to implement a first operation of setting the magnetic memory element to be in a first state. The first operation includes a first preliminary operation of applying a first pulse voltage; and a first setting operation of applying a second pulse voltage having a second rising time to the magnetic memory element after the first preliminary operation.
    Type: Application
    Filed: March 12, 2013
    Publication date: March 27, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Daisuke SAIDA, Minoru AMANO, Naoharu SHIMOMURA
  • Publication number: 20140084402
    Abstract: According to one embodiment, a magnetic memory includes a first magnetoresistive element includes a storage layer with a perpendicular and variable magnetization, a tunnel barrier layer, and a reference layer with a perpendicular and invariable magnetization, and stacked in order thereof in a first direction, and a first shift corrective layer with a perpendicular and invariable magnetization, the first shift corrective layer and the storage layer arranged in a direction intersecting with the first direction. Magnetization directions of the reference layer and the first shift corrective layer are the same.
    Type: Application
    Filed: March 15, 2013
    Publication date: March 27, 2014
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Naoharu SHIMOMURA, Eiji Kitagawa, Chikayoshi Kamata, Minoru Amano, Yuichi Ohsawa, Daisuke Saida, Megumi Yakabe, Hiroaki Maekawa
  • Publication number: 20140078807
    Abstract: An example magnetic recording device includes a magnetic recording section and a magnetization oscillator and a first nonmagnetic layer disposed between the magnetic recording section and the magnetization oscillator. The magnetic recording section includes a first ferromagnetic layer with a magnetization substantially fixed in a first direction; a second ferromagnetic layer with a variable magnetization direction; and a second nonmagnetic layer disposed between the first ferromagnetic layer and the second ferromagnetic layer. The magnetization oscillator includes a third ferromagnetic layer with a variable magnetization direction; a fourth ferromagnetic layer with a magnetization substantially fixed in a second direction; and a third nonmagnetic layer disposed between the third ferromagnetic layer and the fourth ferromagnetic layer.
    Type: Application
    Filed: November 12, 2013
    Publication date: March 20, 2014
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Shiho NAKAMURA, Hirofumi MORISE, Satoshi YANAGI, Daisuke SAIDA, Akira KIKITSU
  • Patent number: 8611142
    Abstract: An example magnetic recording device includes a laminated body. The laminated body includes 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; a third ferromagnetic layer with a variable magnetization direction; and a fourth ferromagnetic layer with a magnetization substantially fixed in a second direction, wherein at least one of the first and second direction is generally perpendicular to the film plane. The magnetization direction of the second ferromagnetic layer is determinable in response to the orientation of a current, by passing the current in a direction generally perpendicular to the film plane of the layers of the laminated body and the magnetization of the third ferromagnetic layer is able to undergo precession by passing the current.
    Type: Grant
    Filed: November 17, 2011
    Date of Patent: December 17, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shiho Nakamura, Hirofumi Morise, Satoshi Yanagi, Daisuke Saida, Akira Kikitsu
  • Patent number: 8582355
    Abstract: According to one embodiment, a magnetic memory element includes a stacked body including first and second stacked units. The first stacked unit includes first and second ferromagnetic layers and a first nonmagnetic layer. A magnetization of the first ferromagnetic layer is fixed in a direction perpendicular to the first ferromagnetic layer. A magnetization of the second ferromagnetic layer is variable. The first nonmagnetic layer is provided between the first and second ferromagnetic layers. The second stacked unit stacked with the first stacked unit includes third and fourth ferromagnetic layers and a second nonmagnetic layer. A magnetization of the third ferromagnetic layer is variable. The fourth ferromagnetic layer is stacked with the third ferromagnetic layer. A magnetization of the fourth ferromagnetic layer is fixed in a direction perpendicular to the fourth ferromagnetic layer. The second nonmagnetic layer is provided between the third and fourth ferromagnetic layers.
    Type: Grant
    Filed: March 9, 2012
    Date of Patent: November 12, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Daisuke Saida, Minoru Amano, Junichi Ito
  • Patent number: 8576616
    Abstract: According to one embodiment, a magnetic element includes first and second conductive layers, an intermediate interconnection, and first and second stacked units. The intermediate interconnection is provided between the conductive layers. The first stacked unit is provided between the first conductive layer and the interconnection, and includes first and second ferromagnetic layer and a first nonmagnetic layer provided between the first and second ferromagnetic layers. The second stacked unit is provided between the second conductive layer and the interconnection, and includes third and fourth ferromagnetic layers and a second nonmagnetic layer provided between the third and fourth ferromagnetic layers. A magnetization direction of the second ferromagnetic layer is determined by causing a spin-polarized electron and a magnetic field to act on the second ferromagnetic layer.
    Type: Grant
    Filed: September 8, 2011
    Date of Patent: November 5, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Daisuke Saida, Minoru Amano, Junichi Ito, Yuichi Ohsawa, Saori Kashiwada, Chikayoshi Kamata, Tadaomi Daibou
  • Publication number: 20130249024
    Abstract: According to one embodiment, a magnetic memory element includes a stacked body and a conductive shield. The stacked body includes first and second stacked units. The first stacked unit includes first and second ferromagnetic layers and a first nonmagnetic layer. The first ferromagnetic layer has a fixed magnetization in a first direction. A magnetization direction of the second ferromagnetic layer is variable in a second direction. The first nonmagnetic layer is provided between the first and second ferromagnetic layers. The second stacked unit includes a third ferromagnetic layer stacked with the first stacked unit in a stacking direction of the first stacked unit. A magnetization direction of the third ferromagnetic layer is variable in a third direction. The conductive shield is opposed to at least a part of a side surface of the second stacked unit. An electric potential of the conductive shield is controllable.
    Type: Application
    Filed: August 31, 2012
    Publication date: September 26, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Daisuke SAIDA, Minoru Amano, Junichi Ito
  • Publication number: 20130250665
    Abstract: According to one embodiment, a magnetic memory includes a magnetoresistive element. The element includes a first magnetic film having a variable magnetization perpendicular to a film surface, a second magnetic film having an invariable magnetization perpendicular to the film surface, a nonmagnetic film between the first and second magnetic films, a magnetic field application layer including a third magnetic film having a magnetization parallel to the film surface. The third magnetic film applies a magnetic field parallel to the film surface to the first magnetic film. A magnitude of the magnetization of the third magnetic film when supplying a read current is larger than a magnitude of the magnetization of the third magnetic film when supplying a write current.
    Type: Application
    Filed: September 18, 2012
    Publication date: September 26, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Eiji KITAGAWA, Daisuke Saida, Naoharu Shimomura
  • Patent number: 8508979
    Abstract: According to one embodiment, a magnetic recording element includes a stacked body. The stacked body includes a first and a second stacked unit. The first stacked unit includes first and second ferromagnetic layers and a first nonmagnetic layer. The first nonmagnetic layer is provided between the first and second ferromagnetic layers. The second stacked unit is stacked with the first stacked unit and includes third and fourth ferromagnetic layers and a second nonmagnetic layer. The fourth ferromagnetic layer is stacked with the third ferromagnetic layer. The second nonmagnetic layer is provided between the third and fourth ferromagnetic layers. An outer edge of the fourth ferromagnetic layer includes a portion outside an outer edge of the first stacked unit in a plane. A magnetization direction of the second ferromagnetic layer is determined by causing a spin-polarized electron and a rotating magnetic field to act on the second ferromagnetic layer.
    Type: Grant
    Filed: September 8, 2011
    Date of Patent: August 13, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Daisuke Saida, Minoru Amano, Junichi Ito, Yuichi Ohsawa, Saori Kashiwada, Chikayoshi Kamata, Tadaomi Daibou
  • Patent number: 8488375
    Abstract: According to one embodiment, a magnetic recording element includes a stacked body including a first stacked unit and a second stacked unit. The first stacked unit includes a first ferromagnetic layer, a second ferromagnetic layer and a first nonmagnetic layer. Magnetization of the first ferromagnetic layer is substantially fixed in a first direction being perpendicular to a first ferromagnetic layer surface. The second stacked unit includes a third ferromagnetic layer, a fourth ferromagnetic layer and a second nonmagnetic layer. Magnetization of the fourth ferromagnetic layer is substantially fixed in a second direction being perpendicular to a fourth ferromagnetic layer surface. The first direction is opposite to the second direction.
    Type: Grant
    Filed: March 1, 2011
    Date of Patent: July 16, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Daisuke Saida, Minoru Amano, Junichi Ito, Yuichi Ohsawa, Saori Kashiwada, Chikayoshi Kamata, Shigeki Takahashi
  • Publication number: 20130070523
    Abstract: According to one embodiment, a magnetic memory element includes a stacked body including first and second stacked units. The first stacked unit includes first and second ferromagnetic layers and a first nonmagnetic layer. A magnetization of the first ferromagnetic layer is fixed in a direction perpendicular to the first ferromagnetic layer. A magnetization of the second ferromagnetic layer is variable. The first nonmagnetic layer is provided between the first and second ferromagnetic layers. The second stacked unit stacked with the first stacked unit includes third and fourth ferromagnetic layers and a second nonmagnetic layer. A magnetization of the third ferromagnetic layer is variable. The fourth ferromagnetic layer is stacked with the third ferromagnetic layer. A magnetization of the fourth ferromagnetic layer is fixed in a direction perpendicular to the fourth ferromagnetic layer. The second nonmagnetic layer is provided between the third and fourth ferromagnetic layers.
    Type: Application
    Filed: March 9, 2012
    Publication date: March 21, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Daisuke Saida, Minoru Amano, Junichi Ito
  • Publication number: 20130069185
    Abstract: According to one embodiment, a magnetic memory element includes a stacked body including first and second stacked units stacked with each other. The first stacked unit includes first and second ferromagnetic layers and a first nonmagnetic layer provided therebetween. The second stacked unit includes third and fourth ferromagnetic layers and a second nonmagnetic layer provided therebetween. Magnetization of the second and third ferromagnetic layers are variable. Magnetizations of the first and fourth ferromagnetic layers are fixed in a direction perpendicular to the layer surfaces. A cross-sectional area of the third ferromagnetic layer is smaller than a cross-sectional area of the first stacked unit when cut along a plane perpendicular to the stacking direction.
    Type: Application
    Filed: March 9, 2012
    Publication date: March 21, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Daisuke SAIDA, Minoru Amano, Yuichi Ohsawa, Junichi Ito, Hiroaki Yoda
  • Publication number: 20130070522
    Abstract: According to one embodiment, a nonvolatile memory device includes a magnetic memory element and a control unit. The magnetic memory element includes a stacked body including first and second stacked units. The first stacked unit includes a first ferromagnetic layer having a magnetization fixed, a second ferromagnetic layer having a magnetization variable and a first nonmagnetic layer provided between the first and second ferromagnetic layers. The second includes a third ferromagnetic layer having a magnetization rorated by a passed current to produce oscillation, a fourth ferromagnetic layer having a magnetization fixed and a second nonmagnetic layer provided between the third and fourth ferromagnetic layers stacked with each other. A frequency of the oscillation changes in accordance with the direction of the magnetization of the second ferromagnetic layer. The control unit includes a reading unit reading out the magnetization of the second ferromagnetic layer.
    Type: Application
    Filed: March 9, 2012
    Publication date: March 21, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Daisuke Saida, Minoru Amano, Tazumi Nagasawa, Yuichi Ohsawa, Junichi Ito
  • Publication number: 20120241827
    Abstract: A magnetoresistive element according to an embodiment includes: a first to third ferromagnetic layers, and a first nonmagnetic layer, the first and second ferromagnetic layers each having an axis of easy magnetization in a direction perpendicular to a film plane, the third ferromagnetic layer including a plurality of ferromagnetic oscillators generating rotating magnetic fields of different oscillation frequencies from one another. Spin-polarized electrons are injected into the first ferromagnetic layer and induce precession movements in the plurality of ferromagnetic oscillators of the third ferromagnetic layer by flowing a current between the first and third ferromagnetic layers, the rotating magnetic fields are generated by the precession movements and are applied to the first ferromagnetic layer, and at least one of the rotating magnetic fields assists a magnetization switching in the first ferromagnetic layer.
    Type: Application
    Filed: August 16, 2011
    Publication date: September 27, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tadaomi DAIBOU, Minoru Amano, Daisuke Saida, Junichi Ito, Yuichi Ohsawa, Chikayoshi Kamata, Saori Kashiwada, Hiroaki Yoda
  • Publication number: 20120244639
    Abstract: According to one embodiment, a method of manufacturing a magnetic memory, the method includes forming a first magnetic layer having a variable magnetization, forming a tunnel barrier layer on the first magnetic layer, forming a second magnetic layer on the tunnel barrier layer, the second magnetic layer having an invariable magnetization, forming a hard mask layer as a mask on the second magnetic layer, patterning the second magnetic layer by using the mask of the hard mask layer, and executing a GCIB-irradiation by using the mask of the hard mask layer, after the patterning.
    Type: Application
    Filed: September 7, 2011
    Publication date: September 27, 2012
    Inventors: Yuichi OHSAWA, Shigeki Takahashi, Junichi Ito, Daisuke Saida, Kyoichi Suguro, Hiroaki Yoda
  • Publication number: 20120243308
    Abstract: According to one embodiment, a magnetic element includes first and second conductive layers, an intermediate interconnection, and first and second stacked units. The intermediate interconnection is provided between the conductive layers. The first stacked unit is provided between the first conductive layer and the interconnection, and includes first and second ferromagnetic layer and a first nonmagnetic layer provided between the first and second ferromagnetic layers. The second stacked unit is provided between the second conductive layer and the interconnection, and includes third and fourth ferromagnetic layers and a second nonmagnetic layer provided between the third and fourth ferromagnetic layers. A magnetization direction of the second ferromagnetic layer is determined by causing a spin-polarized electron and a magnetic field to act on the second ferromagnetic layer.
    Type: Application
    Filed: September 8, 2011
    Publication date: September 27, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Daisuke SAIDA, Minoru AMANO, Junichi ITO, Yuichi OHSAWA, Saori KASHIWADA, Chikayoshi KAMATA, Tadaomi DAIBOU
  • Publication number: 20120244640
    Abstract: According to one embodiment, a method of manufacturing a multilayer film, the method includes forming a first layer, forming a second layer on the first layer, and transcribing a crystal information of one of the first and second layers to the other one of the first and second layers by executing a GCIB-irradiation to the second layer.
    Type: Application
    Filed: September 7, 2011
    Publication date: September 27, 2012
    Inventors: Yuichi OHSAWA, Shigeki Takahashi, Junichi Ito, Daisuke Saida, Kyoichi Suguro, Hiroaki Yoda
  • Publication number: 20120236633
    Abstract: According to one embodiment, a magnetic recording element includes a stacked body. The stacked body includes a first and a second stacked unit. The first stacked unit includes first and second ferromagnetic layers and a first nonmagnetic layer. The first nonmagnetic layer is provided between the first and second ferromagnetic layers. The second stacked unit is stacked with the first stacked unit and includes third and fourth ferromagnetic layers and a second nonmagnetic layer. The fourth ferromagnetic layer is stacked with the third ferromagnetic layer. The second nonmagnetic layer is provided between the third and fourth ferromagnetic layers. An outer edge of the fourth ferromagnetic layer includes a portion outside an outer edge of the first stacked unit in a plane. A magnetization direction of the second ferromagnetic layer is determined by causing a spin-polarized electron and a rotating magnetic field to act on the second ferromagnetic layer.
    Type: Application
    Filed: September 8, 2011
    Publication date: September 20, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Daisuke SAIDA, Minoru AMANO, Junichi ITO, Yuichi OHSAWA, Saori KASHIWADA, Chikayoshi KAMATA, Tadaomi DAIBOU
  • Publication number: 20120124120
    Abstract: According to an embodiment, an adder includes first and second wave computing units and a threshold wave computing unit. Each of the first and second wave computing units includes a pair of first input sections, a first wave transmission medium having a continuous film including a magnetic body connected to the first input sections, and a first wave detector outputting a result of computation by spin waves induced in the first wave transmission medium by the signals corresponding to the two bit values. The threshold wave computing unit includes a plurality of third input sections, a third wave transmission medium having a continuous film including a magnetic body connected to the third input sections, and a third wave detector a result of computation by spin waves induced in the third wave transmission medium.
    Type: Application
    Filed: January 13, 2012
    Publication date: May 17, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hirofumi Morise, Shiho Nakamura, Daisuke Saida, Tsuyoshi Kondo