Patents by Inventor Masatoshi Sakurai

Masatoshi Sakurai 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: 8551685
    Abstract: According to one embodiment, an ultraviolet-curing resin material for pattern transfer contains at least one of 2-methyl-2-adamantyl acrylate, 2-ethyl-2-adamantyl acrylate, and 1,3-adamantanedimethanol diacrylate, isobornyl acrylate, polyfunctional acrylate, and a polymerization initiator, or contains at least one of the acrylates described above, a polymerization initiator, and fluorine-based alcohol.
    Type: Grant
    Filed: January 10, 2013
    Date of Patent: October 8, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Seiji Morita, Kazuyo Umezawa, Masatoshi Sakurai
  • Publication number: 20130259417
    Abstract: According to an embodiment, a light deflecting element includes a dielectric body, a first electrode, and a second electrode. The second electrode is configured to sandwich the dielectric body with the first electrode so as to apply a voltage to the dielectric body. The second electrode includes orthogonal portions that are substantially orthogonal to an incident direction of a light beam passing through the dielectric body, parallel portions that are substantially parallel to the incident direction of the light beam. The orthogonal portions and the parallel portions are formed in an alternate manner on the light beam incident side of the dielectric body. The second electrode includes a linear sloping portion that slopes in a direction toward intersection with the incident direction of the light beam. The orthogonal portions, the parallel portions, and the linear sloping portion are formed integrally.
    Type: Application
    Filed: December 26, 2012
    Publication date: October 3, 2013
    Inventors: Yuuzo Kamiguchi, Katsuya Sugawara, Masahiro Kanamaru, Keiichiro Yusu, Masatoshi Sakurai
  • Publication number: 20130258452
    Abstract: According to an embodiment, a light deflecting element includes a dielectric body, a first electrode, a second electrode, and a third electrode. Each of the second electrode and third electrode is configured to sandwich the dielectric body with the first electrode. The second electrode includes an electrode having a side that lies substantially orthogonal to an incident direction of a light beam, a side that is substantially parallel to the incident direction, and a side that intersects with the incident direction. The third electrode includes an electrode having a side that is aligned with the second electrode, a side that is substantially parallel to an incident direction of the light beam, and a side that intersects with the light beam, and that slopes in an opposite to that of the side of the second electrode that intersects with the light beam.
    Type: Application
    Filed: December 28, 2012
    Publication date: October 3, 2013
    Inventors: Yuuzo KAMIGUCHI, Masahiro Kanamaru, Katsuya Sugawara, Keiichiro Yusu, Masatoshi Sakurai
  • Patent number: 8533570
    Abstract: According to one embodiment, there is provided a magnetic recording apparatus configured to record data subjected to error correcting coding according to a shingled recording scheme, the magnetic recording apparatus including a magnetic recording medium in which unit bits of the data subjected to error correcting coding are recorded with phase shifted between adjacent tracks, a read head having a width covering a plurality of tracks and configured to read data from the plurality of tracks, and a recording controller configured to record the data subjected to error correcting coding and a parity for the data in the plurality of tracks covered by the read head, in a divided manner.
    Type: Grant
    Filed: August 12, 2011
    Date of Patent: September 10, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Akihiro Itakura, Masatoshi Sakurai
  • Patent number: 8507116
    Abstract: According to one embodiment, a magnetic recording medium includes a substrate, a soft magnetic layer, an underlayer, a magnetic recording layer, and a protective layer, wherein the magnetic recording layer is provided with a pattern including recording portions and non-recording portions, the non-recording portions have a composition that is equal to a composition obtained by demagnetizing the recording portions, the non-recording portions contain at least one metal element selected from the group consisting of vanadium and zirconium and at least one element selected from the group consisting of nitrogen, carbon, boron and oxygen, and the at least one element selected from the group consisting of nitrogen, carbon, boron and oxygen is contained in the non-recording portions at a higher content than the content of the at least one element selected from the group consisting of nitrogen, carbon, boron and oxygen in the recording portions.
    Type: Grant
    Filed: July 1, 2011
    Date of Patent: August 13, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takeshi Iwasaki, Kaori Kimura, Yoshiyuki Kamata, Masatoshi Sakurai
  • Patent number: 8475949
    Abstract: A magnetic recording medium is presented that includes protruded magnetic patterns formed on a substrate, and a nonmagnetic material filled in recesses between the magnetic patterns in which an oxygen concentration thereof is higher at a surface side than at a substrate side. The nonmagnetic material is at least one selected from the group consisting of Si, SiC, SiC—C, SiOC, SiON, Si3N4, Al, AlxOy, Ti and TiOx.
    Type: Grant
    Filed: September 20, 2011
    Date of Patent: July 2, 2013
    Assignee: Kabusihki Kaisha Toshiba
    Inventors: Kaori Kimura, Yoshiyuki Kamata, Satoshi Shirotori, Masatoshi Sakurai
  • Patent number: 8454869
    Abstract: According to one embodiment, this invention determines whether a maximum value Hmax and minimum value Hmin of an HF signal obtained when a data recording portion is irradiated with a laser having a wavelength of 450 nm or less and an NA of 0.6 or more meet (Hmax?Hmin)/Hmax<0.13 . . . (1), or whether a maximum value Hmax, a minimum value Hmin, and a most frequent voltage value Have of a signal level of an HF signal obtained when a data recording portion is irradiated with a laser having a wavelength of 450 nm or less and an NA of 0.6 or more meet Hmax/Have?1.05 . . . (2) and Hmin/Have?0.90 . . . (3).
    Type: Grant
    Filed: October 1, 2009
    Date of Patent: June 4, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazuyo Umezawa, Seiji Morita, Masatoshi Sakurai
  • Patent number: 8440091
    Abstract: According to one embodiment, a method of manufacturing a magnetic recording medium comprises forming a protective film on a ferromagnetic recording layer containing Cobalt (Co) on a substrate and forming a recess in both the protective film and the ferromagnetic recording layer at a part where a nonmagnetic layer is to be formed. The method further comprises removing Co from a part of the recess of the ferromagnetic recording layer to form the nonmagnetic layer that separates magnetic patterns made of the ferromagnetic recording layer containing Co. The nonmagnetic layer has an identical chemical composition as the ferromagnetic recording layer, except for the nonmagnetic layer having a lower Co concentration than the magnetic patterns.
    Type: Grant
    Filed: December 15, 2009
    Date of Patent: May 14, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kaori Kimura, Yoshiyuki Kamata, Satoshi Shirotori, Masatoshi Sakurai
  • Patent number: 8419952
    Abstract: According to one embodiment, a method of manufacturing a patterned medium includes forming an implantation depth-adjusting layer above a magnetic recording layer, the magnetic recording layer being made of a material that is deactivated when implanted with a chemical species, and the implantation depth-adjusting layer being made of a material that is etched when irradiated with an ion beam of the chemical species and irradiating the implantation depth-adjusting layer with the ion beam to implant the chemical species into a part of the magnetic recording layer through the implantation depth-adjusting layer while etching the implantation depth-adjusting layer by an action of the ion beam to decrease a thickness of the implantation depth-adjusting layer.
    Type: Grant
    Filed: June 22, 2011
    Date of Patent: April 16, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masatoshi Sakurai, Kaori Kimura, Hiroyuki Hyodo, Takeshi Iwasaki
  • Publication number: 20130077459
    Abstract: In a recording and reproducing apparatus, an optical disc is rotated in a rotating direction and an optical system focuses a laser beam on the optical disc to form a beam spot on the optical disc. The optical system is provided with a scanner which deflects the laser beam along a radial direction of the optical disc in such a manner that the beam spot follows a first scan trajectory along a first direction crossing the rotating direction and a second scan trajectory along a second direction different from the first direction. A first data track with a sequence of recording pits along the first scan trajectory is formed and arranged on the optical disc.
    Type: Application
    Filed: June 29, 2012
    Publication date: March 28, 2013
    Inventors: Yuuzo KAMIGUCHI, Masahiro KANAMARU, Katsuya SUGAWARA, Keiichiro YUSU, Masatoshi SAKURAI, Kazuki MATSUMOTO, Takehiro HIRAMATSU
  • Publication number: 20130056441
    Abstract: A manufacturing method of a magnetic recording medium according to one embodiment includes forming a mask layer having a pattern regularly arranged in a longitudinal direction on a magnetic recording medium containing a substrate and a magnetic recording layer, forming a recording portion having a magnetic pattern and a non-recording portion by patterning the magnetic recording layer, and submitting the mask layer to a peeling liquid to peel the mask layer. The mask layer contains a lamination layer of a lift-off layer, a first hard mask, and a second hard mask. The second hard mask is formed of a material that is different from the material of the first hard disk and the material is dissolvable in the same peeling liquid as the peeling liquid that dissolves the lift-off layer.
    Type: Application
    Filed: July 5, 2012
    Publication date: March 7, 2013
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Kaori Kimura, Kazutaka Takizawa, Masatoshi Sakurai, Akihiko Takeo
  • Patent number: 8372253
    Abstract: According to one embodiment, patterns of protrusions and recesses includes a substrate including a conductive region on at least one major surface, and a projecting pattern layer formed on the conductive region on the major surface, and made of a microcrystalline material, a polycrystalline material, an amorphous material, or an oxide of the microcrystalline, polycrystalline, or amorphous material.
    Type: Grant
    Filed: November 19, 2010
    Date of Patent: February 12, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Satoshi Shirotori, Yoshiyuki Kamata, Takuya Shimada, Masatoshi Sakurai
  • Patent number: 8372575
    Abstract: According to one embodiment, an ultraviolet-curing resin material for pattern transfer contains at least one of 2-methyl-2-adamantyl acrylate, 2-ethyl-2-adamantyl acrylate, and 1,3-adamantanedimethanol diacrylate, isobornyl acrylate, polyfunctional acrylate, and a polymerization initiator, or contains at least one of the acrylates described above, a polymerization initiator, and fluorine-based alcohol.
    Type: Grant
    Filed: March 12, 2010
    Date of Patent: February 12, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Seiji Morita, Kazuyo Umezawa, Masatoshi Sakurai
  • Patent number: 8349163
    Abstract: According to one embodiment, an electroforming master comprises a patterns of protrusions and recesses formed on one major surface of an Si substrate having two major surfaces, corresponding to information for positioning of a read/write head (a preamble, address, and burst), recording tracks or recording bits. Impurity ions are doped in the surface of this patterns of protrusions and recesses. The impurity ion concentration distribution in the film thickness direction of the Si substrate has a peak in a portion from the patterns of protrusions and recesses surface to a depth of 40 nm in the film thickness direction. The impurity concentration of this peak is 1×1020 to 2×1021 ions/cm3.
    Type: Grant
    Filed: December 6, 2010
    Date of Patent: January 8, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Satoshi Shirotori, Akira Watanabe, Yoshiyuki Kamata, Masatoshi Sakurai
  • Publication number: 20130004661
    Abstract: A magnetic recording medium has recording regions including patterns of a magnetic material corresponding to servo signals and recording tracks, non-recording regions including an oxide of the magnetic material formed between the recording regions, and surface oxide films including an oxide of the magnetic material formed on surfaces of the recording regions.
    Type: Application
    Filed: September 12, 2012
    Publication date: January 3, 2013
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Masatoshi SAKURAI
  • Patent number: 8343362
    Abstract: According to one embodiment, when forming first, second, and third stampers by transferring three-dimensional patterns of a master, a height adjusting layer having a film thickness greater on the upper surface of a projection than on the bottom surface of a recess is formed between the second stamper and a second release layer, and the surface of the third stamper is etched with an acidic solution having a pH of less than 3.
    Type: Grant
    Filed: December 17, 2009
    Date of Patent: January 1, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takuya Shimada, Shinobu Sugimura, Yoshiyuki Kamata, Masatoshi Sakurai
  • Patent number: 8333899
    Abstract: According to one embodiment, a method of manufacturing a magnetic recording medium includes forming on a magnetic recording layer a first hard mask, a second hard mask, a third hard mask and a resist, imprinting the resist with a stamper, removing a residue left in the recesses of the patterned resist, etching the third hard mask by use of the patterned resist as a mask, etching the second hard mask by use of the third hard mask as a mask, etching the first hard mask by use of the second hard mask as a mask, forming a pattern of the magnetic recording layer with ion beam irradiation, and removing the first hard mask by use of a remover liquid with higher reactivity to the metal material of the first hard mask than to a constituent element of the magnetic recording layer.
    Type: Grant
    Filed: January 14, 2011
    Date of Patent: December 18, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masatoshi Sakurai, Kaori Kimura, Yousuke Isowaki, Akira Watanabe, Yoshiyuki Kamata
  • Publication number: 20120307403
    Abstract: According to one embodiment, a magnetic recording medium includes: a data area on which a plurality of first magnetic dots are arranged at predetermined positions to record information; a servo area on which a plurality of second magnetic dots for specifying the positions of said plurality of first magnetic dots are arranged at predetermined positions; and servo frames configured so that a frequency of said servo frames is 2 N per circumference of said medium having a radius, that said servo frames are radially discontinuous, and that said servo frame and a space-area, on which no servo frames exist, are alternately radially arranged at a cycle W.
    Type: Application
    Filed: February 13, 2012
    Publication date: December 6, 2012
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Kazuto KASHIWAGI, Makoto Asakura, Haruhiko Izumi, Masatoshi Sakurai
  • Patent number: 8318331
    Abstract: According to one embodiment, a magnetic recording medium includes a substrate, and a magnetic recording layer formed on the substrate and having patterns of protrusions and recesses corresponding to a servo area and a recording area, in which the magnetic recording layer located in each of the recesses in the recording area has a thickness smaller than two thirds of a thickness of the magnetic recording layer corresponding to each of the protrusions, the magnetic recording layer remaining in each of the recesses in the recording area has a thickness of 1 nm or more, and a difference in height on a surface of the magnetic recording medium is 7 nm or less.
    Type: Grant
    Filed: November 20, 2007
    Date of Patent: November 27, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masatoshi Sakurai, Yoshiyuki Kamata, Satoshi Shirotori
  • Patent number: 8308965
    Abstract: According to one embodiment, a stamper manufacturing method includes forming a conductive material concentration gradient layer including the projections pattern, and a composition ratio of a buffering agent to a conductive material in the conductive material concentration gradient layer reducing in a thickness direction from a master side.
    Type: Grant
    Filed: April 25, 2011
    Date of Patent: November 13, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masatoshi Sakurai, Satoshi Shirotori, Seiji Morita, Shinobu Sugimura, Takuya Shimada, Yoshiyuki Kamata