Patents by Inventor Shunji Ishio

Shunji Ishio 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: 20160163345
    Abstract: The present invention provides: a method of producing, at low temperature, a magnetic recording medium comprising an L10FePt thin film which is highly (001)-oriented and highly L10-ordered; and a magnetic recording medium comprising an L10FePt thin film that can be obtained by this method. In the production method of a magnetic recording medium (10), a thin film formation step S1 of forming a thin film 2 containing an FePt alloy and an oxide of metal having a melting point of 100° C. or more and 500° C. or less is carried out; an annealing step S2 of annealing the thin film 2 to a predetermined temperature is carried out; thereby a magnetic recording layer 2? containing the FePt alloy having a L10-ordered structure and the oxide of metal is formed. The magnetic recording medium can be obtained by this production method.
    Type: Application
    Filed: February 11, 2016
    Publication date: June 9, 2016
    Inventors: Shunji ISHIO, Shun SHIBATA
  • Publication number: 20130034748
    Abstract: The present invention provides: a method of producing, at low temperature, a magnetic recording medium comprising an L10FePt thin film which is highly (001)-oriented and highly L10-ordered; and a magnetic recording medium comprising an L10FePt thin film that can be obtained by this method. In the production method of a magnetic recording medium (10), a thin film formation step S1 of forming a thin film 2 containing an FePt alloy and an oxide of metal having a melting point of 100° C. or more and 500° C. or less is carried out; an annealing step S2 of annealing the thin film 2 to a predetermined temperature is carried out; thereby a magnetic recording layer 2? containing the FePt alloy having a L10-ordered structure and the oxide of metal is formed. The magnetic recording medium can be obtained by this production method.
    Type: Application
    Filed: April 21, 2011
    Publication date: February 7, 2013
    Applicant: AKITA UNIVERSITY
    Inventors: Shunji Ishio, Shun Shibata
  • Patent number: 7927725
    Abstract: A magnetic recording medium for use in digital magnetic recording, which comprises a nonmagnetic substrate having deposited thereon a magnetic layer, wherein with respect to the in-plane direction, the magnetic recording layer comprises a plurality of ferromagnetic regions separated from each other by an antiferromagnetic region. A production method of the magnetic recording medium and a magnetic disc apparatus are also disclosed.
    Type: Grant
    Filed: September 8, 2008
    Date of Patent: April 19, 2011
    Assignees: Showa Denko K.K., National University Corporation Akita University
    Inventors: Shunji Ishio, Hitoshi Saito, Takashi Hasegawa, Iwao Okamoto, Naoya Yamamoto
  • Patent number: 7560921
    Abstract: A coersive force distribution analyzing, apparatus applies a magnetic field substantially perpendicularly to a sample including a perpendicularly magnetically recordable magnetic thin film. While tow-dimensionally moving the sample, the coersive force distribution analyzing apparatus generates a magnetic flux detection signal in response to a leakage flux generated in a magnetic domain on a sample surface. The apparatus applies, to the sample, a first external magnetic field and a second external magnetic field respectively corresponding to a first threshold and a second threshold selected from a hysteresis characteristic corresponding to average magnetization of the sample. This results in first magnetic domain image data and second magnetic domain image data. The apparatus uses the first and second thresholds to binarize the first and second image data to generate a first coersive force distribution pattern corresponding to the difference between the binarized first and second image data.
    Type: Grant
    Filed: June 15, 2005
    Date of Patent: July 14, 2009
    Assignee: Japan Science and Technology Agency
    Inventors: Shunji Ishio, Hitoshi Saito
  • Publication number: 20090161254
    Abstract: A magnetic recording medium for use in digital magnetic recording, which comprises a nonmagnetic substrate having deposited thereon a magnetic layer, wherein with respect to the in-plane direction, the magnetic recording layer comprises a plurality of ferromagnetic regions separated from each other by an antiferromagnetic region. A production method of the magnetic recording medium and a magnetic disc apparatus are also disclosed.
    Type: Application
    Filed: September 8, 2008
    Publication date: June 25, 2009
    Applicants: FUJITSU LIMITED, NATIONAL UNIVERSITY CORPORATION AKITA UNIVERSITY
    Inventors: Shunji Ishio, Hitoshi Saito, Takashi Hasegawa, Iwao Okamoto, Naoya Yamamoto
  • Publication number: 20080284422
    Abstract: In a coercive force distribution analysis device, a magnetic field is applied in substantially vertical direction to a sample having a magnetic thin film capable of recording vertical magnetism. A magnetic flux detection signal is generated in accordance with the leaking magnetic flux generated from a magnetic domain of the sample surface while the sample is horizontally moved. A first and a second external magnetic field corresponding to a first and a second threshold value selected from hysteresis characteristic corresponding to the sample average magnetization are applied to the sample so as to generate image data on a first and a second magnetic domain. The first and the second image data are subjected to digitization processing by the first and the second threshold value and the difference between them is generated as a first coercive force distribution pattern.
    Type: Application
    Filed: June 15, 2005
    Publication date: November 20, 2008
    Applicant: JAPAN SCIENCE AND TECHNOLOGY AGENCY
    Inventors: Shunji Ishio, Hitoshi Saito
  • Publication number: 20050220991
    Abstract: At least one ion 6 selected from Nb, Al, Cr and Mo is locally implanted into a thin film 4 containing, as main components, at least one of Fe and Co and at least one of Pd and Pt and a heat treatment is then carried out, and a portion 7 into which at least one ion 6 selected from Nb, Al, Cr and Mo is implanted becomes a portion 9 having a small coercive force and a portion 8 into which at least one ion 6 selected from Nb, Al, Cr and Mo is not locally implanted becomes a portion 10 having a large coercive force.
    Type: Application
    Filed: February 11, 2005
    Publication date: October 6, 2005
    Applicant: TDK Corporation
    Inventors: Tsutomu Aoyama, Shunji Ishio, Hirotaka Ito
  • Publication number: 20050220990
    Abstract: An Ag ion 6 is locally implanted into a thin film 4 containing, as main components, at least one of Fe and Co and at least one of Pd and Pt and a heat treatment is then carried out, and a portion 7 into which the Ag ion 6 is implanted becomes a portion 9 having a large coercive force and a portion 8 into which the Ag ion 6 is not locally implanted becomes a portion 10 having a small coercive force.
    Type: Application
    Filed: February 4, 2005
    Publication date: October 6, 2005
    Applicant: TDK Corporation
    Inventors: Tsutomu Aoyama, Shunji Ishio, Hirotaka Ito
  • Publication number: 20050214450
    Abstract: A thin film 4 containing, as main components, at least one of Fe and Co and at least one of Pd and Pt is heat treated and at least one ion 6 selected from B, Cr, Nb and Ga is locally implanted into a film 5 obtained after the heat treatment, and a portion 7 into which at least one ion 6 selected from B, Cr, Nb and Ga is locally implanted becomes a portion 9 having a small coercive force and a portion 8 into which at least one ion 6 selected from B, Cr, Nb and Ga is not locally implanted becomes a portion 10 having a large coercive force.
    Type: Application
    Filed: February 11, 2005
    Publication date: September 29, 2005
    Applicant: TDK Corporation
    Inventors: Tsutomu Aoyama, Shunji Ishio, Hirotaka Ito
  • Publication number: 20050196546
    Abstract: At least one ion 6 selected from Cr, Al, Nb and Mo is locally implanted into a thin film 4 containing, as main components, at least one of Fe and Co and at least one of Pd and Pt and a boron ion 20 is then implanted into a whole surface of the thin film subjected to the implantation, and a heat treatment is thereafter carried out, and a portion 7 into which at least one ion 6 selected from Cr, Al, Nb and Mo and the boron ion 20 are implanted becomes a portion 9 having a small coercive force and a portion 8 into which only the boron ion 20 is implanted becomes a portion 10 having a large coercive force.
    Type: Application
    Filed: February 8, 2005
    Publication date: September 8, 2005
    Applicant: TDK Corporation
    Inventors: Tsutomu Aoyama, Shunji Ishio, Hirotaka Ito
  • Publication number: 20050175790
    Abstract: A boron ion 6 is locally implanted into a thin film 4 containing, as main components, at least one of Fe and Co and at least one of Pd and Pt and a heat treatment is then carried out, and a portion 7 into which the boron ion 6 is implanted becomes a portion 9 having a large coercive force and a portion 8 into which the boron ion 6 is not locally implanted becomes a portion 10 having a small coercive force.
    Type: Application
    Filed: February 4, 2005
    Publication date: August 11, 2005
    Applicant: TDK Corporation
    Inventors: Tsutomu Aoyama, Shunji Ishio, Hirotaka Ito