Patents by Inventor Yoshishige Suzuki

Yoshishige Suzuki 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: 10431303
    Abstract: A resistance change type memory includes a variable resistance element connected between first and second bit lines and a write control circuit including first and second transistors each including a terminal connected to the first bit line. The write control circuit controls write to the variable resistance element. The write control circuit supplies a second voltage to the first bit line with a first pulse width via the second transistor in the ON state after supplying a first voltage to the first bit line via the first transistor.
    Type: Grant
    Filed: November 30, 2017
    Date of Patent: October 1, 2019
    Assignee: NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Takayuki Nozaki, Yoshishige Suzuki, Shinji Yuasa, Yoichi Shiota, Takurou Ikeura, Hiroki Noguchi, Kazutaka Ikegami
  • Publication number: 20180158525
    Abstract: According to one embodiment, a resistance change type memory includes: a variable resistance element connected between first and second bit lines; a write control circuit including first and second transistors with terminals connected to the first and second bit lines, respectively, and controlling write to the variable resistance element; a first interconnect supplied with a first voltage and connected to the first bit line via the first transistor; and a second interconnect supplied with a second voltage higher than the first voltage, and connected to the first bit line via the second transistor. The write control circuit supplies the second voltage to the first bit line with a first pulse width via the second transistor in the ON state after supplying the first voltage to the first bit line via the first transistor.
    Type: Application
    Filed: November 30, 2017
    Publication date: June 7, 2018
    Applicant: National Institute of Advanced Science and Technology
    Inventors: Takayuki Nozaki, Yoshishige Suzuki, Shinji Yuasa, Yoichi Shiota, Takurou Ikeura, Hiroki Noguchi, Kazutaka Ikegami
  • Patent number: 9460769
    Abstract: To realize an electric field-driven type ferromagnetic resonance excitation method of low power consumption using an electric field as drive power, and provide a spin wave signal generation element and a spin current signal generation element using the method, a logic element using the elements, and a magnetic function element such as a high-frequency detection element and a magnetic recording device using the method. A magnetic field having a specific magnetic field application angle and magnetic field strength is applied to a laminate structure in which an ultrathin ferromagnetic layer sufficiently thin so that an electric field shield effect by conduction electrons does not occur and a magnetic anisotropy control layer are directly stacked on each other and an insulation barrier layer and an electrode layer are arranged in order on an ultrathin ferromagnetic layer side.
    Type: Grant
    Filed: June 18, 2012
    Date of Patent: October 4, 2016
    Assignee: National Institute of Advanced Industrial Science and Technology
    Inventors: Takayuki Nozaki, Yoshishige Suzuki
  • Patent number: 9088243
    Abstract: The embodiments herein relate to a magnetic field feedback based spintronic microwave oscillator driven by DC current. The microwave oscillator works based on a magnetic tunnel junction structure connected to a feedback waveguide. Any fluctuation in the magnetization direction of free magnetization layer of MTJ drives an oscillating current through the feedback waveguide which in turn exerts an oscillating magnetic field on the free layer and amplifies the magnetization fluctuations. If the DC current passing through the MTJ is more than a critical value, continuous processing states of the magnetization are possible. The critical current is independent of the thickness and magnetization of the free layer. A MTJ can be driven into spontaneous oscillations with DC current and magnetic field feedback circuit and can act as a spintronic microwave oscillator.
    Type: Grant
    Filed: September 10, 2013
    Date of Patent: July 21, 2015
    Inventors: Ashwin Tulapurkar, Chakkalakal Tomy, Yoshishige Suzuki, Dinesh Kumar, Katsunori Konishi
  • Publication number: 20150085569
    Abstract: To realize an electric field-driven type ferromagnetic resonance excitation method of low power consumption using an electric field as drive power, and provide a spin wave signal generation element and a spin current signal generation element using the method, a logic element using the elements, and a magnetic function element such as a high-frequency detection element and a magnetic recording device using the method. A magnetic field having a specific magnetic field application angle and magnetic field strength is applied to a laminate structure in which an ultrathin ferromagnetic layer sufficiently thin so that an electric field shield effect by conduction electrons does not occur and a magnetic anisotropy control layer are directly stacked on each other and an insulation barrier layer and an electrode layer are arranged in order on an ultrathin ferromagnetic layer side.
    Type: Application
    Filed: June 18, 2012
    Publication date: March 26, 2015
    Applicant: National Institute of Advanced Industrial Science and Technology
    Inventors: Takayuki Nozaki, Yoshishige Suzuki
  • Patent number: 8787077
    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: Grant
    Filed: March 18, 2013
    Date of Patent: July 22, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Daisuke Saida, Naoharu Shimomura, Minoru Amano, Eiji Kitagawa, Yoshishige Suzuki
  • 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: 20140070896
    Abstract: The embodiments herein relate to a magnetic field feedback based spintronic microwave oscillator driven by DC current. The microwave oscillator works based on a magnetic tunnel junction structure connected to a feedback waveguide. Any fluctuation in the magnetization direction of free magnetization layer of MTJ drives an oscillating current through the feedback waveguide which in turn exerts an oscillating magnetic field on the free layer and amplifies the magnetization fluctuations. If the DC current passing through the MTJ is more than a critical value, continuous processing states of the magnetization are possible. The critical current is independent of the thickness and magnetization of the free layer. A MTJ can be driven into spontaneous oscillations with DC current and magnetic field feedback circuit and can act as a spintronic microwave oscillator.
    Type: Application
    Filed: September 10, 2013
    Publication date: March 13, 2014
    Applicant: Indian Institute of Technology Bombay
    Inventors: Ashwin Tulapurkar, Chakkalakal Tomy, Yoshishige Suzuki, Dinesh Kumar, Katsunori Konishi
  • Patent number: 8013408
    Abstract: A magneto-resistive device has a magnetic free layer (33), a magnetic pinned layer (31) having a magnetic moment larger than that of the magnetic free layer, and an intermediate layer (32) provided between the magnetic free layer and the magnetic pinned layer. The negative-resistance device is characterized in that the negative-resistance device shows negative resistance by making the magnetic free layer continually change the magnetization direction along with the increase of the voltage which is applied to a magneto-resistive device so that electrons flow into the negative-resistance device from a magnetic free layer side.
    Type: Grant
    Filed: May 19, 2009
    Date of Patent: September 6, 2011
    Assignee: Canon Anelva Corporation
    Inventors: Hiroki Maehara, Hitoshi Kubota, Akio Fukushima, Shinji Yuasa, Yoshishige Suzuki, Yoshinori Nagamine
  • Publication number: 20110049659
    Abstract: The present invention provides a magnetization control method controlling, utilizing no current-induced magnetic field or spin transfer torque a magnetization direction with low power consumption, an information storage method, an information storage element, and a magnetic function element. The magnetization control method involves controlling a magnetization direction of a magnetic layer, and includes: forming a structure including (i) the magnetic layer which is an ultrathin film ferromagnetic layer having a film thickness of one or more atomic layers and of 2 nm or less, and (ii) an insulating layer provided on the ultrathin film ferromagnetic layer and working as a potential barrier; and controlling a magnetization direction of the ultrathin film ferromagnetic layer by applying either (i) a voltage to opposing electrodes sandwiching the structure and a base layer or (ii) an electric field to the structure to change magnetic anisotropy of the ultrathin film ferromagnetic layer.
    Type: Application
    Filed: February 27, 2009
    Publication date: March 3, 2011
    Inventors: Yoshishige Suzuki, Takayuki Nozaki, Takuto Maruyama, Yoichi Shiota
  • Patent number: 7764136
    Abstract: A strip line integrated microwave generating element and a microwave detecting element comprises a signal electrode and a ground electrode. The element has a magnetic tunnel junction structure which includes a magnetization fixed layer, a MgO tunnel barrier layer, and a magnetization free layer. The magnetization free layer is 200 nm square or smaller in a cross-sectional area. The magnetization fixed layer is in contact with either one of the signal electrode and the ground electrode while the magnetization free layer of the element being in contact with the other. The element is smaller than the electrodes and mounted on a part of the signal electrode or the ground electrode. A MR ratio of the element is of 100% or more. A resistance value of the element is from 50? to 300?. The resistance of the element is matched with an impedance of the microwave transmission line.
    Type: Grant
    Filed: March 17, 2006
    Date of Patent: July 27, 2010
    Assignee: Japan Science and Technology Agency
    Inventors: Yoshishige Suzuki, Shinji Yuasa, Akio Fukushima, Ashwin Tulapurkar
  • Publication number: 20090322419
    Abstract: An amplifying apparatus includes a magneto-resistive device which has a magnetic free layer, a magnetic pinned layer having a magnetic moment larger than that of the magnetic free layer, and an intermediate layer provided in between the magnetic free layer and the magnetic pinned layer. The amplifying apparatus has a first electrode layer provided in a magnetic free layer side of the magneto-resistive device, and a second electrode layer provided in a magnetic pinned layer side of the magneto-resistive device. The amplifying apparatus further includes a direct-current bias power-source for applying a direct-current bias to the magneto-resistive device, and a load resistor. The amplifying apparatus continually causes the change of a magnetization direction of the magnetic free layer to make the magneto-resistive device show negative resistance, and thereby amplifies an input signal.
    Type: Application
    Filed: July 20, 2009
    Publication date: December 31, 2009
    Applicant: CANON ANELVA CORPORATION
    Inventors: Hiroki Maehara, Hitoshi Kubota, Akio Fukushima, Shinji Yuasa, Yoshishige Suzuki, Yoshinori Nagamine
  • Publication number: 20090261436
    Abstract: A magneto-resistive device has a magnetic free layer (33), a magnetic pinned layer (31) having a magnetic moment larger than that of the magnetic free layer, and an intermediate layer (32) provided between the magnetic free layer and the magnetic pinned layer. The negative-resistance device is characterized in that the negative-resistance device shows negative resistance by making the magnetic free layer continually change the magnetization direction along with the increase of the voltage which is applied to a magneto-resistive device so that electrons flow into the negative-resistance device from a magnetic free layer side.
    Type: Application
    Filed: May 19, 2009
    Publication date: October 22, 2009
    Applicant: CANON ANELVA CORPORATION
    Inventors: Hiroki Maehara, Hitoshi Kubota, Akio Fukushima, Shinji Yuasa, Yoshishige Suzuki, Yoshinori Nagamine
  • Patent number: 7514160
    Abstract: By varying only the thickness of a known material having superior magnetic characteristics to increase spin polarization without changing the chemical composition, a tunnel magnetoresistive element capable of producing a larger magnetoresistive effect is provided. The tunnel magnetoresistive element includes an underlayer (nonmagnetic or antiferromagnetic metal film); an ultrathin ferromagnetic layer disposed on the underlayer; an insulating layer disposed on the ultrathin ferromagnetic layer; and a ferromagnetic electrode disposed on the insulating layer.
    Type: Grant
    Filed: February 12, 2007
    Date of Patent: April 7, 2009
    Assignees: National Institute of Advanced Industrial Science and Technology, Japan Science and Technology Agency
    Inventors: Taro Nagahama, Shinji Yuasa, Yoshishige Suzuki
  • Publication number: 20080150643
    Abstract: Microwave generating and detection portions of a electronic circuit is improved in efficiency and reduced in size. A microwave generating element A comprises a lower electrode 1, a layer 3 formed on the lower electrode 1 in an island shape, forming a magnetoresistance element, an insulator 7 formed on the lower electrode 1 in such a manner as to surround the layer 3 forming the magnetoresistance element, and an upper electrode 5 formed on the insulator 7 and the layer 3 forming the magnetoresistance element. The layer 3 forming the magnetoresistance element includes, in order from the side of the lower electrode 1, a magnetization fixed layer 3a, an intermediate layer 3b, and a magnetization free layer 3c. The magnetization free layer 3c, which is required to produce resonance oscillation based on a current, preferably is dimensioned to be equal to or smaller than 200 nm square in a cross-sectional area and on the order of 1 to 5 nm in film thickness, for example.
    Type: Application
    Filed: March 17, 2006
    Publication date: June 26, 2008
    Inventors: Yoshishige Suzuki, Shinji Yuasa, Akio Fukushima, Ashwin Tulapurkar
  • Publication number: 20070128470
    Abstract: By varying only the thickness of a known material having superior magnetic characteristics to increase spin polarization without changing the chemical composition, a tunnel magnetoresistive element capable of producing a larger magnetoresistive effect is provided. The tunnel magnetoresistive element includes an underlayer (nonmagnetic or antiferromagnetic metal film); an ultrathin ferromagnetic layer disposed on the underlayer; an insulating layer disposed on the ultrathin ferromagnetic layer; and a ferromagnetic electrode disposed on the insulating layer.
    Type: Application
    Filed: February 12, 2007
    Publication date: June 7, 2007
    Applicants: National Inst. of Advanced Ind. Science and Tech., JAPAN SCIENCE AND TECHNOLOGY AGENCY
    Inventors: Taro Nagahama, Shinji Yuasa, Yoshishige Suzuki
  • Patent number: 7220498
    Abstract: By varying only the thickness of a known material having superior magnetic characteristics to increase spin polarization without changing the chemical composition, a tunnel magnetoresistive element capable of producing a larger magnetoresistive effect is provided. The tunnel magnetoresistive element includes an underlayer (nonmagnetic or antiferromagnetic metal film); an ultrathin ferromagnetic layer disposed on the underlayer; an insulating layer disposed on the ultrathin ferromagnetic layer; and a ferromagnetic electrode disposed on the insulating layer.
    Type: Grant
    Filed: May 24, 2002
    Date of Patent: May 22, 2007
    Assignees: National Institute of Advanced Industrial Science and Technology, Japan Science and Technology Agency
    Inventors: Taro Nagahama, Shinji Yuasa, Yoshishige Suzuki
  • Publication number: 20040144995
    Abstract: By varying only the thickness of a known material having superior magnetic characteristics to increase spin polarization without changing the chemical composition, a tunnel magnetoresistive element capable of producing a larger magnetoresistive effect is provided.
    Type: Application
    Filed: November 26, 2003
    Publication date: July 29, 2004
    Inventors: Taro Nagahama, Shinji Yuasa, Yoshishige Suzuki