Patents by Inventor Yousuke Isowaki

Yousuke Isowaki 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: 8017023
    Abstract: According to one embodiment, a method of manufacturing a magnetic recording medium includes forming a resist on a magnetic recording layer, imprinting a stamper to the resist to transfer patterns of protrusions and recesses, and partially etching the magnetic recording layer in areas not covered with patterns of the resist used as masks by ion beam etching using a mixed gas of He and N2 as well as modifying a remainder of the magnetic recording layer to leave behind a nonmagnetic layer having a reduced thickness.
    Type: Grant
    Filed: September 14, 2010
    Date of Patent: September 13, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiyuki Kamata, Kaori Kimura, Yousuke Isowaki, Masatoshi Sakurai
  • Patent number: 8012361
    Abstract: According to one embodiment, a method of manufacturing a magnetic recording medium includes forming a first hard mask, a second hard mask and a resist on a magnetic recording layer, imprinting a stamper to the resist to transfer patterns of protrusions and recesses to the resist, removing residues remaining in the recesses of the patterned resist, etching the second hard mask by using the patterned resist as a mask to transfer the patterns of protrusions and recesses to the second hard mask, etching the first hard mask by using the second hard mask as a mask to transfer the patterns of protrusions and recesses to the first hard mask, removing the second hard mask remaining on the protrusions of the first hard mask, and deactivating the magnetic recording layer exposed in the recesses by means of ion beam irradiation.
    Type: Grant
    Filed: February 12, 2010
    Date of Patent: September 6, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kaori Kimura, Yousuke Isowaki, Yoshiyuki Kamata, Masatoshi Sakurai
  • Patent number: 8002997
    Abstract: According to one embodiment, a method of manufacturing a magnetic recording medium includes forming a resist on a magnetic recording layer, imprinting a stamper to the resist to transfer patterns of protrusions and recesses, and partially etching the magnetic recording layer in areas not covered with patterns of the resist used as masks by ion beam etching using a mixed gas of He and N2 as well as modifying a remainder of the magnetic recording layer to leave behind a nonmagnetic layer having a reduced thickness.
    Type: Grant
    Filed: August 20, 2009
    Date of Patent: August 23, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoshiyuki Kamata, Kaori Kimura, Yousuke Isowaki, Masatoshi Sakurai
  • Patent number: 7993536
    Abstract: According to one embodiment, a method of manufacturing a magnetic recording medium includes forming a first hard mask, a second hard mask and a resist film on a magnetic recording layer, imprinting a stamper on the resist film to transfer patterns of recesses and protrusions, removing residues remained in recess of the patterned resist film, etching the second hard mask using the patterned resist film as a mask to transfer patterns of recesses and protrusions, etching the first hard mask using the patterned second hard mask as a mask to transfer patterns of recesses and protrusions, and deactivating magnetism of the magnetic recording layer exposed in the recesses together with removing the second hard mask by ion-beam etching.
    Type: Grant
    Filed: December 11, 2009
    Date of Patent: August 9, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yousuke Isowaki, Kaori Kimura, Yoshiyuki Kamata, Masatoshi Sakurai
  • Patent number: 7972523
    Abstract: According to one embodiment, a method of manufacturing a magnetic recording medium includes forming a magnetic recording layer, an oxidation inhibiting layer, a hard mask layer includes carbon on a substrate, coating the hard mask layer with a resist, transferring patterns of protrusions and recesses to the resist by imprinting to form resist patterns, sequentially performing etching of the hard mask layer using the resist patterns as masks, etching of the oxidation inhibiting layer, and etching and/or magnetism deactivation of the magnetic recording layer to form patterns of the magnetic recording layer, and sequentially performing stripping of the resist patterns, stripping of the hard mask layer and stripping of the oxidation inhibiting layer, in which ion beam etching is used for stripping the oxidation inhibiting layer.
    Type: Grant
    Filed: July 24, 2009
    Date of Patent: July 5, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kaori Kimura, Yousuke Isowaki, Yoshiyuki Kamata, Masatoshi Sakurai
  • Patent number: 7967993
    Abstract: According to one embodiment, a method of manufacturing a magnetic recording medium includes forming a hard mask and a resist on a magnetic recording layer, imprinting a stamper on the resist to transfer patterns of protrusions and recesses, removing resist residues left in the recesses of the patterned resist, etching the hard mask using the patterned resist as a mask to transfer the patterns of protrusions and recesses, stripping the resist, and performing ion beam etching to remove the remaining hard mask and to modify a surface of the magnetic recording layer uncovered with the remaining hard mask.
    Type: Grant
    Filed: July 23, 2009
    Date of Patent: June 28, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yousuke Isowaki, Kaori Kimura, Yoshiyuki Kamata, Masatoshi Sakurai
  • Publication number: 20110014496
    Abstract: According to one embodiment, there is provided a method of manufacturing a magnetic recording medium, including forming a first hard mask including carbon as a main component, a second hard mask including a main component other than carbon and a resist on a magnetic recording layer, contacting a stamper to the resist to transfer patterns of protrusions and recesses to the resist, removing residues in the recesses of the patterned resist, etching the second hard mask, etching the first hard mask, patterning the magnetic recording layer, and removing the first hard mask, the method further including, between etching the first hard mask and removing the first hard mask, removing the second hard mask remaining on the protrusions of the first hard mask, and removing a contaminating layer on a surface of the first hard mask by a mixed gas of oxygen-based gas and a fluorine compound.
    Type: Application
    Filed: July 16, 2010
    Publication date: January 20, 2011
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Kaori KIMURA, Yousuke ISOWAKI, Yoshiyuki KAMATA, Masatoshi SAKURAI
  • Publication number: 20110000880
    Abstract: According to one embodiment, a method of manufacturing a magnetic recording medium includes forming a resist on a magnetic recording layer, imprinting a stamper to the resist to transfer patterns of protrusions and recesses, and partially etching the magnetic recording layer in areas not covered with patterns of the resist used as masks by ion beam etching using a mixed gas of He and N2 as well as modifying a remainder of the magnetic recording layer to leave behind a nonmagnetic layer having a reduced thickness.
    Type: Application
    Filed: September 14, 2010
    Publication date: January 6, 2011
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Yoshiyuki Kamata, Kaori Kimura, Yousuke Isowaki, Masatoshi Sakurai
  • Publication number: 20100214695
    Abstract: According to one embodiment, a method of manufacturing a magnetic recording medium includes forming a first hard mask, a second hard mask and a resist on a magnetic recording layer, imprinting a stamper to the resist to transfer patterns of protrusions and recesses to the resist, removing residues remaining in the recesses of the patterned resist by means of a first etching gas, etching the second hard mask by means of the first etching gas using the patterned resist as a mask to transfer the patterns to the second hard mask, etching the first hard mask by means of a second etching gas different from the first etching gas using the second hard mask as a mask to transfer the patterns to the first hard mask, and performing ion beam etching in order to deactivate the magnetic recording layer exposed in the recesses and to remove the second hard mask.
    Type: Application
    Filed: February 12, 2010
    Publication date: August 26, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yousuke Isowaki, Kaori Kimura, Yoshiyuki Kamata, Masatoshi Sakurai
  • Publication number: 20100215989
    Abstract: According to one embodiment, a method of manufacturing a magnetic recording medium includes forming a first hard mask, a second hard mask and a resist on a magnetic recording layer, imprinting a stamper to the resist to transfer patterns of protrusions and recesses to the resist, removing residues remaining in the recesses of the patterned resist, etching the second hard mask by using the patterned resist as a mask to transfer the patterns of protrusions and recesses to the second hard mask, etching the first hard mask by using the second hard mask as a mask to transfer the patterns of protrusions and recesses to the first hard mask, subjecting the magnetic recording layer exposed in the recesses to modifying treatment to change an etching rate, and deactivating the magnetic recording layer exposed in the recesses.
    Type: Application
    Filed: February 12, 2010
    Publication date: August 26, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yousuke ISOWAKI, Kaori KIMURA, Yoshiyuki KAMATA, Masatoshi SAKURAI
  • Publication number: 20100214694
    Abstract: According to one embodiment, a method of manufacturing a magnetic recording medium includes forming a first hard mask, a second hard mask and a resist on a magnetic recording layer, imprinting a stamper to the resist to transfer patterns of protrusions and recesses to the resist, removing residues remaining in the recesses of the patterned resist, etching the second hard mask by using the patterned resist as a mask to transfer the patterns of protrusions and recesses to the second hard mask, etching the first hard mask by using the second hard mask as a mask to transfer the patterns of protrusions and recesses to the first hard mask, removing the second hard mask remaining on the protrusions of the first hard mask, and deactivating the magnetic recording layer exposed in the recesses by means of ion beam irradiation.
    Type: Application
    Filed: February 12, 2010
    Publication date: August 26, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Kaori KIMURA, Yousuke ISOWAKI, Yoshiyuki KAMATA, Masatoshi SAKURAI
  • Publication number: 20100147791
    Abstract: According to one embodiment, a method of manufacturing a magnetic recording medium includes forming a first hard mask, a second hard mask and a resist film on a magnetic recording layer, imprinting a stamper on the resist film to transfer patterns of recesses and protrusions, removing residues remained in recess of the patterned resist film, etching the second hard mask using the patterned resist film as a mask to transfer patterns of recesses and protrusions, etching the first hard mask using the patterned second hard mask as a mask to transfer patterns of recesses and protrusions, and deactivating magnetism of the magnetic recording layer exposed in the recesses together with removing the second hard mask by ion-beam etching.
    Type: Application
    Filed: December 11, 2009
    Publication date: June 17, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yousuke ISOWAKI, Kaori KIMURA, Yoshiyuki KAMATA, Masatoshi SAKURAI
  • Publication number: 20100047625
    Abstract: According to one embodiment, a method of manufacturing a magnetic recording medium includes forming a resist on a magnetic recording layer, imprinting a stamper to the resist to transfer patterns of protrusions and recesses, and partially etching the magnetic recording layer in areas not covered with patterns of the resist used as masks by ion beam etching using a mixed gas of He and N2 as well as modifying a remainder of the magnetic recording layer to leave behind a nonmagnetic layer having a reduced thickness.
    Type: Application
    Filed: August 20, 2009
    Publication date: February 25, 2010
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Yoshiyuki KAMATA, Kaori KIMURA, Yousuke ISOWAKI, Masatoshi SAKURAI
  • Publication number: 20100018947
    Abstract: According to one embodiment, a method of manufacturing a magnetic recording medium includes forming a magnetic recording layer, an oxidation inhibiting layer, a hard mask layer includes carbon on a substrate, coating the hard mask layer with a resist, transferring patterns of protrusions and recesses to the resist by imprinting to form resist patterns, sequentially performing etching of the hard mask layer using the resist patterns as masks, etching of the oxidation inhibiting layer, and etching and/or magnetism deactivation of the magnetic recording layer to form patterns of the magnetic recording layer, and sequentially performing stripping of the resist patterns, stripping of the hard mask layer and stripping of the oxidation inhibiting layer, in which ion beam etching is used for stripping the oxidation inhibiting layer.
    Type: Application
    Filed: July 24, 2009
    Publication date: January 28, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Kaori Kimura, Yousuke Isowaki, Yoshiyuki Kamata, Masatoshi Sakurai
  • Publication number: 20100018946
    Abstract: According to one embodiment, a method of manufacturing a magnetic recording medium includes forming a hard mask and a resist on a magnetic recording layer, imprinting a stamper on the resist to transfer patterns of protrusions and recesses, removing resist residues left in the recesses of the patterned resist, etching the hard mask using the patterned resist as a mask to transfer the patterns of protrusions and recesses, stripping the resist, and performing ion beam etching to remove the remaining hard mask and to modify a surface of the magnetic recording layer uncovered with the remaining hard mask.
    Type: Application
    Filed: July 23, 2009
    Publication date: January 28, 2010
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yousuke Isowaki, Kaori Kimura, Yoshiyuki Kamata, Masatoshi Sakurai
  • Publication number: 20090201607
    Abstract: It is made possible to provide a patterned perpendicular magnetic recording medium that has smaller write magnetic field and the variation of magnetic characteristics in the bit regions, generates fewer reversed magnetic domains in the position control information regions of the head, and has excellent thermal stability. A patterned perpendicular magnetic recording medium includes: a nonmagnetic substrate; a soft magnetic base layer formed on the nonmagnetic substrate; a nonmagnetic intermediate layer formed on the soft magnetic base layer; and a perpendicular magnetic recording layer formed on the nonmagnetic intermediate layer, and including a stacked structure of a CoPt-based crystalline film having a Pt content in the range of 5 atomic percent to 35 atomic percent and a rare-earth and transition metal alloy amorphous film formed on the CoPt-based crystalline film. The CoPt-based crystalline film and the rare-earth and transition metal alloy amorphous film are exchange-coupled.
    Type: Application
    Filed: January 29, 2009
    Publication date: August 13, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yousuke Isowaki, Tomoyuki Maeda, Yoshiyuki Kamata
  • Publication number: 20090135519
    Abstract: A magnetic recording medium includes a disk substrate, and recording cells arrayed on the disk substrate in a track direction, the recording cells includes a ferromagnetic pattern and a magnetic pattern formed on one of two sidewalls of the ferromagnetic pattern in the track direction and having a lower crystalline magnetic anisotropy constant Ku than that of the ferromagnetic pattern.
    Type: Application
    Filed: November 20, 2008
    Publication date: May 28, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Hiroyuki Hieda, Kazuto Kashiwagi, Akira Kikitsu, Yousuke Isowaki, Yoshiyuki Kamata