Patents by Inventor Eiji Kitagawa

Eiji Kitagawa 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: 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
  • Patent number: 8680633
    Abstract: A magnetoresistive element according to an embodiment includes a first magnetic layer, a second magnetic layer, and a first nonmagnetic layer provided between the first magnetic layer and the second magnetic layer, the first magnetic layer including a magnetic film of MnxGey (77 atm %?x?82 atm %, 18 atm %?y?23 atm %, x+y=100 atm %).
    Type: Grant
    Filed: March 14, 2013
    Date of Patent: March 25, 2014
    Assignees: Kabushiki Kaisha Toshiba, Tohoku University
    Inventors: Yushi Kato, Tadaomi Daibou, Eiji Kitagawa, Takao Ochiai, Takahide Kubota, Shigemi Mizukami, Terunobu Miyazaki
  • Patent number: 8682524
    Abstract: A view control system is communicably connected to a display device for displaying data in accordance with an information resource. The view control system includes a view control device. The view control device includes a regulation determiner, a view regulator, and a resource data sender. The regulation determiner determines whether to regulate visible output of the information resource. The view regulator associates regulatory data with the information resource upon determining to regulate visible output of the information resource. The resource data sender sends resource data including the information resource, associated regulatory data, and a message conveying that visible output of the information resource is regulated. Either the message or data generated in accordance with the information resource is sent to the display device.
    Type: Grant
    Filed: June 22, 2009
    Date of Patent: March 25, 2014
    Assignee: Fujitsu Limited
    Inventor: Eiji Kitagawa
  • Patent number: 8670268
    Abstract: According to one embodiment, a magnetoresistive element includes first and second magnetic layers and a first nonmagnetic layer. The first magnetic layer has an axis of easy magnetization perpendicular to a film plane, and a variable magnetization. The second magnetic layer has an axis of easy magnetization perpendicular to a film plane, and an invariable magnetization. The first nonmagnetic layer is provided between the first and second magnetic layers. The second magnetic layer includes third and fourth magnetic layers, and a second nonmagnetic layer formed between the third and fourth magnetic layers. The third magnetic layer is in contact with the first nonmagnetic layer and includes Co and at least one of Zr, Nb, Mo, Hf, Ta, and W.
    Type: Grant
    Filed: March 22, 2012
    Date of Patent: March 11, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Toshihiko Nagase, Eiji Kitagawa, Katsuya Nishiyama, Tadashi Kai, Koji Ueda, Daisuke Watanabe
  • Patent number: 8669628
    Abstract: According to one embodiment, a magnetoresistive element includes the following configuration. First nonmagnetic layer is provided between the first magnetic layer (storage layer) and the second magnetic layer (reference layer). Third magnetic layer is formed on a surface of the storage layer, which is opposite to a surface on which the first nonmagnetic layer is formed. Fourth magnetic layer is formed on a surface of the reference layer, which is opposite to a surface on which the first nonmagnetic layer is formed. The third and fourth magnetic layers have a magnetization antiparallel to the magnetization of the storage layer. Second nonmagnetic layer is located between the storage and third magnetic layers. Third nonmagnetic layer is located between the reference and fourth magnetic layers. The thickness of the fourth magnetic layer is smaller than that of the third magnetic layer.
    Type: Grant
    Filed: March 19, 2012
    Date of Patent: March 11, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Ueda, Katsuya Nishiyama, Toshihiko Nagase, Daisuke Watanabe, Eiji Kitagawa, Tadashi Kai
  • Patent number: 8665639
    Abstract: According to one embodiment, a magnetoresistive element includes a first magnetic layer with a perpendicular and variable magnetization, a second magnetic layer with a perpendicular and invariable magnetization, and a first nonmagnetic layer between the first and second magnetic layer. The first magnetic layer has a laminated structure of first and second ferromagnetic materials. A magnetization direction of the first magnetic layer is changed by a current which pass through the first magnetic layer, the first nonmagnetic layer and the second magnetic layer. A perpendicular magnetic anisotropy of the second ferromagnetic material is smaller than that of the first ferromagnetic material. A film thickness of the first ferromagnetic material is thinner than that of the second ferromagnetic material.
    Type: Grant
    Filed: February 28, 2012
    Date of Patent: March 4, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Toshihiko Nagase, Tadashi Kai, Katsuya Nishiyama, Eiji Kitagawa, Tadaomi Daibou, Masahiko Nakayama, Makoto Nagamine, Shigeto Fukatsu, Masatoshi Yoshikawa, Hiroaki Yoda
  • Publication number: 20130307099
    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: Application
    Filed: December 28, 2012
    Publication date: November 21, 2013
    Inventors: Eiji KITAGAWA, Chikayoshi Kamata, Saori Kashiwada, Yushi Kato, Tadaomi Daibou
  • Publication number: 20130288397
    Abstract: According to one embodiment, a magnetoresistive effect element includes a first magnetic layer including perpendicular anisotropy to a film surface and an invariable magnetization direction, the first magnetic layer having a magnetic film including an element selected from a first group including Tb, Gd, and Dy and an element selected from a second group including Co and Fe, a second magnetic layer including perpendicular magnetic anisotropy to the film surface and a variable magnetization direction, and a nonmagnetic layer between the first magnetic layer and the second magnetic layer. The magnetic film includes amorphous phases and crystals whose particle sizes are 0.5 nm or more.
    Type: Application
    Filed: July 1, 2013
    Publication date: October 31, 2013
    Inventors: Eiji Kitagawa, Tadaomi Daibou, Yutaka Hashimoto, Masaru Tokou, Tadashi Kai, Makato Nagamine, Toshihiko Nagase, Katsuya Nishiyama, Koji Ueda, Hiroaki Yoda, Kay Yakushiji, Shinji Yuasa, Hitoshi Kubota, Taro Nagahama, Akio Fukushima, Koji Ando
  • Patent number: 8547737
    Abstract: A magnetoresistive element according to an embodiment includes: a first ferromagnetic layer having an axis of easy magnetization in a direction perpendicular to a film plane; a second ferromagnetic layer having an axis of easy magnetization in a direction perpendicular to a film plane; a nonmagnetic layer placed between the first ferromagnetic layer and the second ferromagnetic layer; a first interfacial magnetic layer placed between the first ferromagnetic layer and the nonmagnetic layer; and a second interfacial magnetic layer placed between the second ferromagnetic layer and the nonmagnetic layer. The first interfacial magnetic layer includes a first interfacial magnetic film, a second interfacial magnetic film placed between the first interfacial magnetic film and the nonmagnetic layer and having a different composition from that of the first interfacial magnetic film, and a first nonmagnetic film placed between the first interfacial magnetic film and the second interfacial magnetic film.
    Type: Grant
    Filed: September 27, 2012
    Date of Patent: October 1, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tadaomi Daibou, Eiji Kitagawa, Yutaka Hashimoto, Masaru Tokou, Toshihiko Nagase, Katsuya Nishiyama, Koji Ueda, Makoto Nagamine, Tadashi Kai, Hiroaki Yoda
  • Publication number: 20130249026
    Abstract: According to one embodiment, a magnetoresistive element includes a first magnetic film having a variable magnetization direction, a second magnetic film having an invariable magnetization direction, and a magnesium oxide film provided between the first magnetic film and the second magnetic film and being in contact with both the first magnetic film and the second magnetic film, and doped with at least one element selected from a first group consisting of copper, silver, and gold.
    Type: Application
    Filed: September 18, 2012
    Publication date: September 26, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Eiji KITAGAWA, Tadaomi DAIBOU, Yushi KATO
  • 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
  • Publication number: 20130249025
    Abstract: According to one embodiment, a magnetoresistive element includes a bottom electrode, a first magnetic layer with an magnetic axis substantially perpendicular to a film plane thereof, a first interface layer, an MgO insulating layer, a second interface layer, a second magnetic layer with an magnetic axis nearly perpendicular to a film plane thereof, and a top electrode. The magnetoresistive element has a diffusion barrier layer between the first magnetic layer and the first interface layer when the first magnetic layer contains Pt or Pd, and a diffusion barrier layer between the second magnetic layer and the second interface layer when the second magnetic layer contains Pt or Pd. The diffusion barrier layer is an Hf film of thickness 0.6 nm to 0.8 nm.
    Type: Application
    Filed: September 8, 2012
    Publication date: September 26, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Katsuaki NATORI, Toshihiko Nagase, Eiji Kitagawa, Tadashi Kai
  • Patent number: 8530987
    Abstract: A magnetic memory includes a magnetoresistive element. The magnetoresistive element includes a reference layer having an invariable magnetization direction, a storage layer having a variable magnetization direction, and a spacer layer provided between the reference layer and the storage layer. The storage layer has a multilayered structure including first and second magnetic layers, the second magnetic layer is provided between the first magnetic layer and the spacer layer and has a magnetic anisotropy energy lower than that of the first magnetic layer, and an exchange coupling constant Jex between the first magnetic layer and the second magnetic layer is not more than 5 erg/cm2.
    Type: Grant
    Filed: March 28, 2012
    Date of Patent: September 10, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hisanori Aikawa, Tadashi Kai, Masahiko Nakayama, Sumio Ikegawa, Naoharu Shimomura, Eiji Kitagawa, Tatsuya Kishi, Jyunichi Ozeki, Hiroaki Yoda, Satoshi Yanagi
  • Patent number: 8531875
    Abstract: According to one embodiment, a magnetic memory includes at least one memory cell including a magnetoresistive element, and first and second electrodes. The element includes a first magnetic layer, a tunnel barrier layer, a second magnetic layer, and a third magnetic layer provided on the second magnetic layer and having a magnetization antiparallel to the magnetization direction of the second magnetic layer. A diameter of an upper surface of the first magnetic layer is smaller than that of a lower surface of the tunnel barrier layer. A diameter of a lower surface of the second magnetic layer is not more than that of an upper surface of the tunnel barrier layer.
    Type: Grant
    Filed: March 21, 2012
    Date of Patent: September 10, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Satoshi Yanagi, Eiji Kitagawa, Masahiko Nakayama, Jyunichi Ozeki, Hisanori Aikawa, Naoharu Shimomura, Masatoshi Yoshikawa, Minoru Amano, Shigeki Takahashi, Hiroaki Yoda
  • Patent number: 8530887
    Abstract: A magnetoresistive element according to an embodiment includes: a first magnetic layer; a tunnel barrier layer on the first magnetic layer; a second magnetic layer placed on the tunnel barrier layer and containing CoFe; and a nonmagnetic layer placed on the second magnetic layer, and containing nitrogen and at least one element selected from the group consisting of B, Ta, Zr, Al, and Ce.
    Type: Grant
    Filed: March 17, 2011
    Date of Patent: September 10, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Eiji Kitagawa, Tadashi Kai, Tadaomi Daibou, Yutaka Hashimoto, Hiroaki Yoda
  • Patent number: 8520433
    Abstract: A magnetoresistive element according to an embodiment includes a first magnetic layer, a second magnetic layer, and a first nonmagnetic layer provided between the first magnetic layer and the second magnetic layer, at least one of the first magnetic layer and the second magnetic layer including a magnetic film of MnxAlyGez (10 atm %?x?44 atm %, 10 atm %?y?65 atm %, 10 atm %?z?80 atm %, x+y+z=100 atm %).
    Type: Grant
    Filed: September 20, 2012
    Date of Patent: August 27, 2013
    Assignees: Kabushiki Kaisha Toshiba, Tohoku University
    Inventors: Yushi Kato, Tadaomi Daibou, Eiji Kitagawa, Takahide Kubota, Shigemi Mizukami, Terunobu Miyazaki
  • Patent number: 8502331
    Abstract: According to one embodiment, a magnetoresistive effect element includes a first magnetic layer including perpendicular anisotropy to a film surface and an invariable magnetization direction, the first magnetic layer having a magnetic film including an element selected from a first group including Tb, Gd, and Dy and an element selected from a second group including Co and Fe, a second magnetic layer including perpendicular magnetic anisotropy to the film surface and a variable magnetization direction, and a nonmagnetic layer between the first magnetic layer and the second magnetic layer. The magnetic film includes amorphous phases and crystals whose particle sizes are 0.5 nm or more.
    Type: Grant
    Filed: September 16, 2011
    Date of Patent: August 6, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Eiji Kitagawa, Tadaomi Daibou, Yutaka Hashimoto, Masaru Tokou, Tadashi Kai, Makoto Nagamine, Toshihiko Nagase, Katsuya Nishiyama, Koji Ueda, Hiroaki Yoda, Kay Yakushiji, Shinji Yuasa, Hitoshi Kubota, Taro Nagahama, Akio Fukushima, Koji Ando
  • Patent number: 8472242
    Abstract: A magnetoresistive effect memory of an aspect of the present invention including a magnetoresistive effect element including a first magnetic layer having an invariable magnetization direction, a second magnetic layer having a variable magnetization direction, and an interlayer provided between the first magnetic layer and the second magnetic layer, and a reading circuit which passes a pulse-shaped read current through the magnetoresistive effect element to read data stored in the magnetoresistive effect element, wherein the pulse width of the read current is shorter than a period from an initial state to a cooperative coherent precession movement of magnetizations included in the second magnetic layer.
    Type: Grant
    Filed: March 29, 2010
    Date of Patent: June 25, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Naoharu Shimomura, Eiji Kitagawa, Sumio Ikegawa, Yoshihisa Iwata
  • Patent number: 8423279
    Abstract: A drive assist apparatus includes: a road-information storage unit storing road information; a traffic-signal information storage unit to store information regarding a traffic-signal change timing; a receiving unit to receive other-vehicle information; an obtaining unit to obtain host-vehicle information; a determining unit to determine whether the other vehicle becomes an obstacle to the host vehicle; and a calculating unit to calculate a recommended speed based on the host-vehicle information, the road information, and information regarding the traffic-signal change timing, when the other vehicle is determined to not become an obstacle to the host vehicle, and calculate the recommended speed based on the host-vehicle information, the road information, the information regarding the traffic-signal change timing, and an arrival delay time for avoiding an obstacle caused by the other vehicle, when the other vehicle is determined to become the obstacle to the host vehicle.
    Type: Grant
    Filed: November 24, 2010
    Date of Patent: April 16, 2013
    Assignee: Fujitsu Limited
    Inventors: Eiji Kitagawa, Takuro Ikeda