Patents by Inventor Kazuya Sawada

Kazuya Sawada 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: 10586917
    Abstract: Provided is a method for fabricating an electronic device including a variable resistance element which includes a free layer formed over a substrate and having a changeable magnetization direction, a pinned layer having a pinned magnetization direction, a tunnel barrier layer interposed between the free layer and the pinned layer, and a magnetic correction layer suitable for reducing the influence of a stray field generated by the pinned layer. The method may include: cooling the substrate; and forming the magnetic correction layer over the cooled substrate.
    Type: Grant
    Filed: November 28, 2018
    Date of Patent: March 10, 2020
    Assignees: SK hynix Inc., TOSHIBA MEMORY CORPORATION
    Inventors: Jong-Koo Lim, Won-Joon Choi, Guk-Cheon Kim, Yang-Kon Kim, Ku-Youl Jung, Toshihiko Nagase, Youngmin Eeh, Daisuke Watanabe, Kazuya Sawada, Makoto Nagamine
  • Patent number: 10573802
    Abstract: According to one embodiment, a magnetic memory device includes a stacked structure that includes a first magnetic layer having a variable magnetization direction, a second magnetic layer having a fixed magnetization direction, and a nonmagnetic layer provided between the first magnetic layer and the second magnetic layer, wherein the entire first magnetic layer exhibits a parallel or antiparallel magnetization direction to the second magnetic layer, and has an anisotropic magnetic field Hk_film within a range from ?1 kOe to +1 kOe.
    Type: Grant
    Filed: September 12, 2018
    Date of Patent: February 25, 2020
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Tatsuya Kishi, Youngmin Eeh, Kazuya Sawada, Masaru Toko
  • Patent number: 10510950
    Abstract: A magnetoresistive memory device includes a first magnetic layer having a variable magnetization direction, a second magnetic layer, a magnetization direction of the second magnetic layer being invariable, a first nonmagnetic layer provided between the first magnetic layer and the second magnetic layer, and a second nonmagnetic layer provided on the first magnetic layer, which is opposite the first nonmagnetic layer. The first magnetic layer has a stacked layer structure in which an amorphous magnetic material layer is sandwiched between crystalline magnetic material layers. The magnetoresistive memory device further includes nonmagnetic material layers provided between one of the crystalline magnetic material layers and the amorphous magnetic material layer, and between the other crystalline magnetic layer and the amorphous magnetic material layer, respectively.
    Type: Grant
    Filed: July 5, 2019
    Date of Patent: December 17, 2019
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Daisuke Watanabe, Toshihiko Nagase, Youngmin Eeh, Kazuya Sawada, Makoto Nagamine, Tadaaki Oikawa, Kenichi Yoshino, Hiroyuki Ohtori
  • Patent number: 10490732
    Abstract: According to one embodiment, a magnetic memory device includes a stacked structure including a first magnetic layer, a second magnetic layer and a nonmagnetic layer between the first magnetic layer and the second magnetic layer, and a sidewall insulating layer provided on a side surface of the stacked structure and containing boron (B).
    Type: Grant
    Filed: September 16, 2016
    Date of Patent: November 26, 2019
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Yasuyuki Sonoda, Daisuke Watanabe, Masatoshi Yoshikawa, Youngmin Eeh, Shuichi Tsubata, Toshihiko Nagase, Yutaka Hashimoto, Kazuya Sawada, Kazuhiro Tomioka, Kenichi Yoshino, Tadaaki Oikawa
  • Patent number: 10468170
    Abstract: According to one embodiment, a magnetic device comprising a magnetoresistive effect element, wherein the magnetoresistive effect element includes: a first ferromagnetic body, a second ferromagnetic body, and a first rare-earth ferromagnetic oxide that is provided between the first ferromagnetic body and the second ferromagnetic body and magnetically joins the first ferromagnetic body and the second ferromagnetic body.
    Type: Grant
    Filed: March 13, 2018
    Date of Patent: November 5, 2019
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Young Min Eeh, Toshihiko Nagase, Daisuke Watanabe, Kazuya Sawada, Tadaaki Oikawa, Kenichi Yoshino
  • Publication number: 20190334081
    Abstract: A magnetoresistive memory device includes a first magnetic layer having a variable magnetization direction, a second magnetic layer, a magnetization direction of the second magnetic layer being invariable, a first nonmagnetic layer provided between the first magnetic layer and the second magnetic layer, and a second nonmagnetic layer provided on the first magnetic layer, which is opposite the first nonmagnetic layer. The first magnetic layer has a stacked layer structure in which an amorphous magnetic material layer is sandwiched between crystalline magnetic material layers. The magnetoresistive memory device further includes nonmagnetic material layers provided between one of the crystalline magnetic material layers and the amorphous magnetic material layer, and between the other crystalline magnetic layer and the amorphous magnetic material layer, respectively.
    Type: Application
    Filed: July 5, 2019
    Publication date: October 31, 2019
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Daisuke WATANABE, Toshihiko NAGASE, Youngmin EEH, Kazuya SAWADA, Makoto NAGAMINE, Tadaaki OIKAWA, Kenichi YOSHINO, Hiroyuki OHTORI
  • Publication number: 20190296226
    Abstract: According to one embodiment, a magnetic device includes a magnetoresistive effect element including a first ferromagnet, a conductor, and an oxide provided between the first ferromagnet and the conductor, the oxide including a first oxide of a rare-earth element and a second oxide of an element of which a covalent radius is smaller than a covalent radius of the rare-earth element.
    Type: Application
    Filed: September 6, 2018
    Publication date: September 26, 2019
    Applicants: TOSHIBA MEMORY CORPORATION, SK HYNIX INC.
    Inventors: Young Min EEH, Daisuke WATANABE, Jae-Hyoung LEE, Toshihiko NAGASE, Kazuya SAWADA, Tadaaki OIKAWA, Kenichi YOSHINO, Taiga ISODA
  • Publication number: 20190288184
    Abstract: According to one embodiment, a magnetic memory device includes a stacked structure that includes a first magnetic layer having a variable magnetization direction, a second magnetic layer having a fixed magnetization direction, and a nonmagnetic layer provided between the first magnetic layer and the second magnetic layer, wherein the entire first magnetic layer exhibits a parallel or antiparallel magnetization direction to the second magnetic layer, and has an anisotropic magnetic field Hk_film within a range from ?1 kOe to +1 kOe.
    Type: Application
    Filed: September 12, 2018
    Publication date: September 19, 2019
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Tatsuya KISHI, Youngmin EEH, Kazuya SAWADA, Masaru TOKO
  • Publication number: 20190259438
    Abstract: A memory device includes a magnetoresistive element including first and second magnetic layers and a non-magnetic layer provided between the first and second magnetic layers. The memory device also includes a write circuit which controls a first writing setting magnetization of the first and second magnetic layers in a parallel state and a second writing setting the magnetization of the first and second magnetic layers in an antiparallel state, and applies a write current to the magnetoresistive element. A first write current in the first writing includes a first pulse and a second pulse added to the first pulse. A width of the second pulse is smaller than a width of the first pulse, and a scurrent level of the second pulse is different from a current level of the first pulse.
    Type: Application
    Filed: May 1, 2019
    Publication date: August 22, 2019
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Tatsuya KISHI, Tsuneo INABA, Daisuke WATANABE, Masahiko NAKAYAMA, Nobuyuki OGATA, Masaru TOKO, Hisanori AIKAWA, Jyunichi OZEKI, Toshihiko NAGASE, Young Min EEH, Kazuya SAWADA
  • Patent number: 10388343
    Abstract: A magnetoresistive element includes: a first magnetic layer having a magnetization direction that is variable; a second magnetic layer having a magnetization direction that is invariable; a first non-magnetic layer provided between the first magnetic layer and the second magnetic layer; a third magnetic layer that fixes the magnetization direction of the second magnetic layer and that antiferromagnetically couples with the second magnetic layer; and a second non-magnetic layer provided between the second magnetic layer and the third magnetic layer. The second non-magnetic layer includes ruthenium (Ru) and a metal element.
    Type: Grant
    Filed: March 9, 2018
    Date of Patent: August 20, 2019
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Tadaaki Oikawa, Young Min Eeh, Kazuya Sawada, Kenichi Yoshino, Toshihiko Nagase, Daisuke Watanabe
  • Patent number: 10325640
    Abstract: According to one embodiment, a memory device includes: a magnetoresistive element including first and second magnetic layers and a non-magnetic layer provided between the first and second magnetic layers; and a write circuit which controls a first writing setting magnetization of the first and second magnetic layers in a parallel state and a second writing setting the magnetization of the first and second magnetic layers in an antiparallel state, and applies a current pulse to the magnetoresistive element. A first pulse pattern used in the first writing is different from a second pulse pattern used in the second writing.
    Type: Grant
    Filed: March 10, 2017
    Date of Patent: June 18, 2019
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Tatsuya Kishi, Tsuneo Inaba, Daisuke Watanabe, Masahiko Nakayama, Nobuyuki Ogata, Masaru Toko, Hisanori Aikawa, Jyunichi Ozeki, Toshihiko Nagase, Young Min Eeh, Kazuya Sawada
  • Patent number: 10263178
    Abstract: According to one embodiment, a magnetic memory device includes a first magnetic layer having a variable magnetization direction, a second magnetic layer having a fixed magnetization direction, and a nonmagnetic layer between the first and second magnetic layers. The second magnetic layer includes a first main surface on the nonmagnetic layer side and a second main surface opposite to the first main surface, and includes a first region on the first main surface side and a second region on the second main surface side, and an intermediate region between the first and second regions and containing a predetermined nonmagnetic element. A concentration of the predetermined nonmagnetic element in the intermediate region is higher than that in the first and second regions. The second magnetic layer contains a magnetic element from the first to second main surfaces.
    Type: Grant
    Filed: March 20, 2017
    Date of Patent: April 16, 2019
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Kazuya Sawada, Toshihiko Nagase, Youngmin Eeh, Daisuke Watanabe, Kenichi Yoshino, Tadaaki Oikawa, Hiroyuki Ohtori
  • Publication number: 20190109280
    Abstract: Provided is a method for fabricating an electronic device including a variable resistance element which includes a free layer formed over a substrate and having a changeable magnetization direction, a pinned layer having a pinned magnetization direction, a tunnel barrier layer interposed between the free layer and the pinned layer, and a magnetic correction layer suitable for reducing the influence of a stray field generated by the pinned layer. The method may include: cooling the substrate; and forming the magnetic correction layer over the cooled substrate.
    Type: Application
    Filed: November 28, 2018
    Publication date: April 11, 2019
    Inventors: Jong-Koo LIM, Won-Joon CHOI, Guk-Cheon KIM, Yang-Kon KIM, Ku-Youl JUNG, Toshihiko NAGASE, Youngmin EEH, Daisuke WATANABE, Kazuya SAWADA, Makoto NAGAMINE
  • Publication number: 20190079873
    Abstract: An electronic device includes semiconductor memory, the semiconductor memory including an under layer; a first magnetic layer located over the under layer and having a variable magnetization direction; a tunnel barrier layer located over the first magnetic layer; and a second magnetic layer located over the tunnel barrier layer and having a pinned magnetization direction, wherein the under layer includes a first metal nitride layer having a NaCl crystal structure and a second metal nitride layer containing a light metal.
    Type: Application
    Filed: November 9, 2018
    Publication date: March 14, 2019
    Inventors: Yang-Kon KIM, Ki-Seon PARK, Bo-Mi LEE, Won-Joon CHOI, Guk-Cheon KIM, Daisuke WATANABE, Makoto NAGAMINE, Young-Min EEH, Koji UEDA, Toshihiko NAGASE, Kazuya SAWADA
  • Publication number: 20190080833
    Abstract: According to one emcodiment, a magnetic device comprising a magnetoresistive effect element, wherein the magnetoresistive effect element; includes: a first ferromagnetic body, a second ferromagnetic body, and a first rare-earth ferromagnetic oxide that is provided between the first ferromagnetic body and the second ferromagnetic body and magnetically joins the first ferromagnetic body and the second ferromagnetic body.
    Type: Application
    Filed: March 13, 2018
    Publication date: March 14, 2019
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Young Min EEH, Toshihiko NAGASE, Daisuke WATANABE, Kazuya SAWADA, Tadaaki OIKAWA, Kenichi YOSHINO
  • Publication number: 20190080739
    Abstract: According to one embodiment, a magnetoresistive element includes: a first magnetic layer having a magnetization direction that is variable; a second magnetic layer having a magnetization direction that is invariable; a first non-magnetic layer provided between the first magnetic layer and the second magnetic layer; a third magnetic layer that fixes the magnetization direction of the second magnetic layer and that antiferromagnetically couples with the second magnetic layer; and a second non-magnetic layer provided between the second magnetic layer and the third magnetic layer. The second non-magnetic layer includes ruthenium (Ru) and a metal element.
    Type: Application
    Filed: March 9, 2018
    Publication date: March 14, 2019
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Tadaaki OIKAWA, Young Min EEH, Kazuya SAWADA, Kenichi YOSHINO, Toshihiko NAGASE, Daisuke WATANABE
  • Patent number: 10203380
    Abstract: An electronic device may include a semiconductor memory, and the semiconductor memory may include a free layer having a variable magnetization direction; a pinned layer having a pinned magnetization direction; and a tunnel barrier layer between the free layer and the pinned layer, wherein the free layer may include a first magnetic layer; a second magnetic layer having a smaller perpendicular magnetic anisotropy energy density than the first magnetic layer; and a spacer interposed between the first magnetic layer and the second magnetic layer.
    Type: Grant
    Filed: December 14, 2017
    Date of Patent: February 12, 2019
    Assignees: SK Hynix Inc., Toshiba Memory Corporation
    Inventors: Ku-Youl Jung, Guk-Cheon Kim, Toshihiko Nagase, Daisuke Watanabe, Won-Joon Choi, Youngmin Eeh, Kazuya Sawada
  • Patent number: 10199568
    Abstract: According to one embodiment, a magnetic storage device includes a substrate, a dummy contact disposed on a top surface of the substrate, extending linearly in a direction substantially perpendicular to the top surface of the substrate, and floating electrically, and a magnetoresistive effect element included in a layer and insulated from the dummy contact, wherein the layer is disposed on the top surface of the dummy contact.
    Type: Grant
    Filed: September 9, 2016
    Date of Patent: February 5, 2019
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Makoto Nagamine, Young Min Eeh, Daisuke Watanabe, Kazuya Sawada, Toshihiko Nagase
  • Publication number: 20190019841
    Abstract: A semiconductor device includes a first rare earth oxide layer, a first magnetic layer adjacent to the first rare earth oxide layer, a second rare earth oxide layer, a second magnetic layer adjacent to the second rare earth oxide layer, and a nonmagnetic layer. The first magnetic layer is disposed between the first rare earth oxide layer and the nonmagnetic layer and is oriented in a crystal surface which is the same as a crystal surface of the nonmagnetic layer. The second magnetic layer is disposed between the second rare earth oxide layer and the nonmagnetic layer and is oriented in a crystal surface which is the same as a crystal surface of the nonmagnetic layer. The nonmagnetic layer is disposed between the first magnetic layer and the second magnetic layer.
    Type: Application
    Filed: September 9, 2018
    Publication date: January 17, 2019
    Applicant: TOSHIBA MEMORY CORPORATION
    Inventors: Youngmin EEH, Toshihiko NAGASE, Daisuke WATANABE, Kazuya SAWADA, Kenichi YOSHINO, Tadaaki OIKAWA, Hiroyuki OHTORI
  • Patent number: 10170519
    Abstract: According to one embodiment, a magnetoresistive element includes a first metal layer having a body-centered cubic structure, a second metal layer having a hexagonal close-packed structure on the first metal layer, a metal nitride layer on the second metal layer, a first magnetic layer on the metal nitride layer, an insulating layer on the first magnetic layer, and a second magnetic layer on the insulating layer.
    Type: Grant
    Filed: September 9, 2016
    Date of Patent: January 1, 2019
    Assignee: TOSHIBA MEMORY CORPORATION
    Inventors: Youngmin Eeh, Toshihiko Nagase, Daisuke Watanabe, Koji Ueda, Makoto Nagamine, Kazuya Sawada