Patents by Inventor Chikayoshi Kamata

Chikayoshi Kamata 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: 20190280186
    Abstract: A magnetic memory according to an embodiment includes: an electrode including a lower face, an upper face opposed to the lower face, and a side face different from the lower and upper faces; a magnetoresistive element disposed on the upper face of the electrode, including a multilayer structure including a first magnetic layer disposed above the upper face of the electrode, a second magnetic layer disposed between the upper face of the electrode and the first magnetic layer, and a nonmagnetic layer disposed between the first magnetic layer and the second magnetic layer; a first insulating film disposed on the side face of the electrode; and a second insulating film including a first portion disposed on a side face of the multilayer structure of the magnetoresistive element, and a second portion, the first insulating film being disposed between the second portion and the side face of the electrode.
    Type: Application
    Filed: August 31, 2018
    Publication date: September 12, 2019
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Saori KASHIWADA, Junichi ITO, Chikayoshi KAMATA, Megumi YAKABE
  • Patent number: 10340311
    Abstract: According to one embodiment, a magnetoresistive effect element includes: a first magnetic layer; a nonmagnetic layer provided on the first magnetic layer; a second magnetic layer provided on the nonmagnetic layer; a first insulating layer provided at least on a side surface of the second magnetic layer; a second insulating layer covering at least a part of the first insulating layer; a conductive layer provided between the first insulating layer and the second insulating layer; and a first electrode including a first portion on the second magnetic layer and a second portion on a side surface of the second insulating layer. A height of a lower surface of the second portion is equal to or less than a height of an upper surface of the conductive layer.
    Type: Grant
    Filed: September 6, 2017
    Date of Patent: July 2, 2019
    Assignee: Toshiba Memory Corporation
    Inventors: Megumi Yakabe, Satoshi Seto, Chikayoshi Kamata, Saori Kashiwada, Junichi Ito
  • Publication number: 20190096461
    Abstract: According to one embodiment, a memory device includes: a first memory element arranged above a substrate; a first contact portion adjacent to the first memory element in a first direction parallel to a surface of the substrate; a second contact portion arranged above the first memory element in a second direction perpendicular to the surface of the substrate; and a second memory element arranged above the first contact portion in the second direction. First dimensions at upper parts of the first and second memory elements are smaller than second dimensions at lower parts of the first and second memory elements, and third dimensions at upper parts of the first and second contact portions are larger than fourth dimensions at lower parts of the first and second contact portions.
    Type: Application
    Filed: March 9, 2018
    Publication date: March 28, 2019
    Applicant: Toshiba Memory Corporation
    Inventors: Masahiro Koike, Shogo Itai, Tadaomi Daibou, Chikayoshi Kamata, Junichi Ito, Masahiko Nakayama
  • Patent number: 10103198
    Abstract: A magnetoresistive element according to an embodiment includes: a multilayer structure including a first magnetic layer, a second magnetic layer disposed above the first magnetic layer, and a nonmagnetic layer disposed between the first magnetic layer and the second magnetic layer; a conductor disposed above the second magnetic layer, and including a lower face, an upper face opposing to the lower face, and a side face that is different from the lower face and the upper face, an area of the lower face of the conductor being smaller than an area of the upper face of the conductor, and smaller than an area of an upper face of the second magnetic layer; and a carbon-containing layer disposed on the side face of the conductor.
    Type: Grant
    Filed: March 7, 2016
    Date of Patent: October 16, 2018
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventors: Saori Kashiwada, Yuichi Ohsawa, Daisuke Saida, Chikayoshi Kamata, Kazutaka Ikegami, Megumi Yakabe, Hiroaki Maekawa
  • Publication number: 20180138237
    Abstract: According to one embodiment, a magnetoresistive effect element includes: a first magnetic layer; a nonmagnetic layer provided on the first magnetic layer; a second magnetic layer provided on the nonmagnetic layer; a first insulating layer provided at least on a side surface of the second magnetic layer; a second insulating layer covering at least a part of the first insulating layer; a conductive layer provided between the first insulating layer and the second insulating layer; and a first electrode including a first portion on the second magnetic layer and a second portion on a side surface of the second insulating layer. A height of a lower surface of the second portion is equal to or less than a height of an upper surface of the conductive layer.
    Type: Application
    Filed: September 6, 2017
    Publication date: May 17, 2018
    Applicant: Toshiba Memory Corporation
    Inventors: Megumi YAKABE, Satoshi SETO, Chikayoshi KAMATA, Saori KASHIWADA, Junichi ITO
  • Patent number: 9935260
    Abstract: According to one embodiment, a magnetic memory device includes a first magnetic layer, a second magnetic layer, a third magnetic layer, and a first non-magnetic layer. The third magnetic layer is provided between a first part of the first magnetic layer and the second magnetic layer. The first non-magnetic layer is provided between the second magnetic layer and the third magnetic layer. The first magnetic layer further includes a second part. At least a portion of the second part overlaps at least a portion of the third magnetic layer in a second direction orthogonal to a first direction from the first part toward the second magnetic layer.
    Type: Grant
    Filed: September 14, 2016
    Date of Patent: April 3, 2018
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Daisuke Saida, Shogo Itai, Chikayoshi Kamata
  • Patent number: 9799482
    Abstract: A device manufacturing apparatus and manufacturing method of a magnetic device. The device manufacturing apparatus can include a substrate holding portion configured to hold a substrate, an ion source, an anode disposed in a housing of the ion source, and a cathode disposed outside the housing of the ion source. A first opening can be disposed in a portion of the housing such the anode is exposed to a region between the anode and the substrate holding portion. The ion source can be configured to generate an ion beam with which the substrate is irradiated. A first structure can be disposed between the ion source and the substrate holding portion. The first structure can have a first through hole through which the ion beam can pass. The first structure can include a conductor, and an opening dimension of the first through hole can be equal to or larger than an opening dimension of the first opening.
    Type: Grant
    Filed: March 11, 2016
    Date of Patent: October 24, 2017
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Yuichi Ohsawa, Akio Ui, Junichi Ito, Chikayoshi Kamata, Megumi Yakabe, Saori Kashiwada
  • Publication number: 20170279037
    Abstract: According to one embodiment, a magnetic memory device includes a first magnetic layer, a second magnetic layer, a third magnetic layer, and a first non-magnetic layer. The third magnetic layer is provided between a first part of the first magnetic layer and the second magnetic layer. The first non-magnetic layer is provided between the second magnetic layer and the third magnetic layer. The first magnetic layer further includes a second part. At least a portion of the second part overlaps at least a portion of the third magnetic layer in a second direction orthogonal to a first direction from the first part toward the second magnetic layer.
    Type: Application
    Filed: September 14, 2016
    Publication date: September 28, 2017
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Daisuke SAIDA, Shogo ITAI, Chikayoshi KAMATA
  • Publication number: 20160380189
    Abstract: According to one embodiment, a manufacturing method of a magnetoresistive effect element includes forming a laminated structure on a substrate, the laminated structure including a first magnetic layer having a variable magnetization direction, a second magnetic layer having an invariable magnetization direction, and a non-magnetic layer between the first and second magnetic layers, forming a first mask layer having a predetermined plane shape on the laminated structure, and processing the laminated structure based on the first mask layer by using an ion beam whose solid angle in a center of the substrate is 10° or more.
    Type: Application
    Filed: September 13, 2016
    Publication date: December 29, 2016
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Yuichi Ohsawa, Junichi Ito, Saori Kashiwada, Chikayoshi Kamata, Naoki Tamaoki
  • Publication number: 20160359107
    Abstract: According to one embodiment, a method of manufacturing a magnetoresistive element, the method includes forming a first magnetic layer, forming a tunnel barrier layer on the first magnetic layer, forming a second magnetic layer on the tunnel barrier layer, forming a hard mask layer on the second magnetic layer, and patterning the second magnetic layer, the tunnel barrier layer, and the first magnetic layer, with a cluster ion beam using the hard mask layer as a mask, wherein the cluster ion beam comprises cluster ions, cluster sizes of the cluster ions are distributed, and a peak value of the distribution of the cluster sizes is 2 pieces or more and 1000 pieces or less.
    Type: Application
    Filed: August 18, 2016
    Publication date: December 8, 2016
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yuichi OHSAWA, Junichi ITO, Shigeki TAKAHASHI, Saori KASHIWADA, Chikayoshi KAMATA
  • Publication number: 20160268338
    Abstract: A magnetoresistive element according to an embodiment includes: a multilayer structure including a first magnetic layer, a second magnetic layer disposed above the first magnetic layer, and a nonmagnetic layer disposed between the first magnetic layer and the second magnetic layer; a conductor disposed above the second magnetic layer, and including a lower face, an upper face opposing to the lower face, and a side face that is different from the lower face and the upper face, an area of the lower face of the conductor being smaller than an area of the upper face of the conductor, and smaller than an area of an upper face of the second magnetic layer; and a carbon-containing layer disposed on the side face of the conductor.
    Type: Application
    Filed: March 7, 2016
    Publication date: September 15, 2016
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Saori KASHIWADA, Yuichi Ohsawa, Daisuke Saida, Chikayoshi Kamata, Kazutaka Ikegami, Megumi Yakabe, Hiroaki Maekawa
  • Publication number: 20160196951
    Abstract: According to one embodiment, a device manufacturing apparatus includes a substrate holding portion holding a substrate; an ion source including a housing, an anode disposed in the housing, a cathode disposed outside the housing, and a first opening disposed in a portion of the housing such that the anode is exposed to a region between the anode and the substrate holding portion, the ion source configured to generate an ion beam with which the substrate is irradiated; and at least one first structure disposed between the ion source and the substrate holding portion, and having a first through hole through which the ion beam passes. The first structure includes a conductor, and an opening dimension of the first through hole is equal to or larger than an opening dimension of the first opening.
    Type: Application
    Filed: March 11, 2016
    Publication date: July 7, 2016
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yuichi OHSAWA, Akio UI, Junichi ITO, Chikayoshi KAMATA, Megumi YAKABE, Saori KASHIWADA
  • Publication number: 20160197268
    Abstract: According to one embodiment, a magnetoresistive effect element includes a first magnetic layer including a first magnetic element; second magnetic layer; an intermediate layer between the first magnetic layer and the second magnetic layer; and a sidewall layer having a laminated structure on a side face of the first magnetic layer. The sidewall layer includes a first layer disposed on the side face of the first magnetic layer and including a first element having an atomic number larger than an atomic number of the first magnetic element, and a second layer including a second element having an atomic number smaller than the atomic number of the first atomic element. The first layer is disposed between the first magnetic layer and the second layer.
    Type: Application
    Filed: March 11, 2016
    Publication date: July 7, 2016
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Megumi YAKABE, Yuichi OHSAWA, Chikayoshi KAMATA, Saori KASHIWADA, Junichi ITO, Eiji KITAGAWA
  • Patent number: 9299918
    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: Grant
    Filed: October 1, 2014
    Date of Patent: March 29, 2016
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tadaomi Daibou, Minoru Amano, Daisuke Saida, Junichi Ito, Yuichi Ohsawa, Chikayoshi Kamata, Saori Kashiwada, Hiroaki Yoda
  • Patent number: 9224944
    Abstract: A magnetic memory according to an embodiment includes: at least one memory cell comprising a magnetoresistive element as a memory element, and first and second electrodes that energize the magnetoresistive element. The magnetoresistive element includes: a first magnetic layer having a variable magnetization direction perpendicular to a film plane; a tunnel barrier layer on the first magnetic layer; and a second magnetic layer on the tunnel barrier layer, and having a fixed magnetization direction perpendicular to the film plane. The first magnetic layer including: a first region; and a second region outside the first region so as to surround the first region, and having a smaller perpendicular magnetic anisotropy energy than that of the first region. The second magnetic layer including: a third region; and a fourth region outside the third region, and having a smaller perpendicular magnetic anisotropy energy than that of the third region.
    Type: Grant
    Filed: March 24, 2014
    Date of Patent: December 29, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Shigeki Takahashi, Yuichi Ohsawa, Junichi Ito, Chikayoshi Kamata, Saori Kashiwada, Minoru Amano, Hiroaki Yoda
  • Patent number: 9117995
    Abstract: A magnetoresistance element includes a first magnetic layer having first and second surfaces, a second magnetic layer, an intermediate layer provided between the first surface and the second magnetic layer, a first layer provided on the second surface, containing B and at least one element selected from Hf, Al, Mg, and Ti and having third and fourth surfaces, a second layer provided on the fourth surface and containing B and at least one element selected from Hf, Al, and Mg, and an insulating layer provided on a sidewall of the intermediate layer and containing at least one element selected from the Hf, Al, and Mg contained in the second layer.
    Type: Grant
    Filed: September 11, 2013
    Date of Patent: August 25, 2015
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tadaomi Daibou, Eiji Kitagawa, Chikayoshi Kamata, Saori Kashiwada, Yushi Kato, Megumi Yakabe
  • Patent number: 9117924
    Abstract: According to one embodiment, a magnetic memory element includes a first magnetic layer having a first surface and a second surface being opposite to the first surface, a second magnetic layer, an intermediate layer which is provided between the first surface of the first magnetic layer and the second magnetic layer, a layer which is provided on the second surface of the first magnetic layer, the layer containing B and at least one element selected from Hf, Al, and Mg, and an insulating layer which is provided on a sidewall of the intermediate layer, the insulating layer containing at least one element selected from the Hf, Al, and Mg contained in the layer.
    Type: Grant
    Filed: December 28, 2012
    Date of Patent: August 25, 2015
    Assignee: KABUSHIKI KAISHA TOSHIBA
    Inventors: Eiji Kitagawa, Chikayoshi Kamata, Saori Kashiwada, Yushi Kato, Tadaomi Daibou
  • Patent number: 8994131
    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: Grant
    Filed: March 15, 2013
    Date of Patent: March 31, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Naoharu Shimomura, Eiji Kitagawa, Chikayoshi Kamata, Minoru Amano, Yuichi Ohsawa, Daisuke Saida, Megumi Yakabe, Hiroaki Maekawa
  • Publication number: 20150014756
    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: October 1, 2014
    Publication date: January 15, 2015
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Tadaomi DAIBOU, Minoru AMANO, Daisuke SAIDA, Junichi ITO, Yuichi OHSAWA, Chikayoshi KAMATA, Saori KASHIWADA, Hiroaki YODA
  • Patent number: 8878317
    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: Grant
    Filed: August 16, 2011
    Date of Patent: November 4, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tadaomi Daibou, Minoru Amano, Daisuke Saida, Junichi Ito, Yuichi Ohsawa, Chikayoshi Kamata, Saori Kashiwada, Hiroaki Yoda