Patents by Inventor Yoichiro Tanaka

Yoichiro Tanaka 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: 6496321
    Abstract: A magnetic recording/reproducing device comprises a recording head for magnetically recording a signal on a magnetic recording medium along a predetermined track, and a reproducing head member including a spin valve typed magnetoresistive element and bias magnetic applying means, associated with the spin valve typed magnetoresistive element, for applying a bias magnetic field to the spin valve typed magnetoresistive element, the reproducing head member for changing a sensitivity distribution in a track width direction based on a distance between the reproducing head and the recording head, and an angle difference between the direction of the reproducing head and the extending direction of the track.
    Type: Grant
    Filed: October 29, 1999
    Date of Patent: December 17, 2002
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yoichiro Tanaka
  • Publication number: 20020136930
    Abstract: Disclosed is a perpendicular magnetic recording medium, comprising a nonmagnetic substrate, a longitudinal hard magnetic multi-layered film arranged on the nonmagnetic substrate, including a nonmagnetic intermediate layer and a pair of hard magnetic layers laminated one upon the other with the nonmagnetic intermediate layer interposed therebetween, and having at least two hard magnetic layers, a longitudinal soft magnetic layer formed on the longitudinal hard magnetic multi-layered film, and a perpendicular magnetic recording layer formed on the longitudinal soft magnetic layer. The perpendicular magnetic recording medium of the particular construction is capable of suppressing noise and achieves a high recording magnetic field intensity and a high recording resolution.
    Type: Application
    Filed: March 21, 2002
    Publication date: September 26, 2002
    Inventors: Soichi Oikawa, Yoichiro Tanaka, Takashi Hikosaka, Futoshi Nakamura
  • Publication number: 20020121436
    Abstract: An apparatus for a physical vapor deposition system includes a target having a sidewall having an undercut thereon defining a net erosion area and a net redeposition area.
    Type: Application
    Filed: July 13, 2001
    Publication date: September 5, 2002
    Applicant: APPLIED MATERIALS, INC.
    Inventors: James Van Gogh, Jim Thompson, Marc Schweitzer, Yoichiro Tanaka, Alan Liu, Anthony CT Chan, Karl Brown, John C. Forster
  • Publication number: 20020089796
    Abstract: This invention provides a perpendicular magnetic recording type disk drive comprised of a double-layered disk medium and a magnetic head containing a read head element containing a GMR element. The GMR element has a linear response dynamic range characteristic larger than an average value of a reproduction magnetic field from a disk 101 and a characteristic capable of avoiding or suppressing saturation phenomenon even if it is affected by a strong reproduction magnetic field from the disk medium.
    Type: Application
    Filed: December 26, 2001
    Publication date: July 11, 2002
    Inventor: Yoichiro Tanaka
  • Publication number: 20020034052
    Abstract: There is disclosed a disk drive having a magnetic device for applying a direct current magnetic field to the disk 1 by using a disk with a double-layered structure in which a soft magnetic layer is provided on a lower layer of the recording magnetic layer. The magnetic device generates a direct current magnetic field to uniform a magnetic domain state of the soft magnetic layer of the disk. The intensity of the direct current is larger than the anisotropic magnetic field of the soft magnetic layer and is smaller than the coercive force of the recording magnetic layer. As a consequence, the stabilization of the magnetic domain state of the soft magnetic layer of the disk can be realized to make an attempt of decreasing the magnetic noise and establishing stabilization with respect to the disturbance magnetic field.
    Type: Application
    Filed: August 31, 2001
    Publication date: March 21, 2002
    Inventors: Akihiko Takeo, Yoichiro Tanaka
  • Patent number: 6296747
    Abstract: A shield assembly for protecting the walls of a plasma sputter reactor from deposition while allowing high flow of processing gas into the processing space of the reactor without the plasma leaking out of the processing space. The shield assembly is particularly useful for reactive sputtering, for example, of TiN or TaN, in which large amounts of nitrogen need to flow into the chamber. The shield assembly includes a primary shield positioned inside of the chamber sidewalls and protecting the sidewalls and preferably also the bottom wall and sides of the pedestal. Multiple holes are formed in the primary shield to pass gas input through a gas inlet in the chamber walls outside of the primary shield. A baffle shield in positioned inside of the primary shield and covers the holes in the primary shield with a gap between the two shields. The baffle shield extends only partway along the primary shield so that gap communicates with the processing space of the reactor.
    Type: Grant
    Filed: June 22, 2000
    Date of Patent: October 2, 2001
    Assignee: Applied Materials, Inc.
    Inventor: Yoichiro Tanaka
  • Patent number: 6210539
    Abstract: An apparatus and method for processing a substrate in the presence of a plasma, the apparatus including: a chamber enclosing a region maintained at a low pressure; a substrate support disposed in the region and having a substantially horizontal substrate support surface for supporting a substrate; and a coil disposed in the chamber and for producing a radio frequency field within the chamber to create an ionizing plasma above the substrate support surface, the coil being disposed for maintaining a plasma having equipotential lines which extend substantially parallel to the upper surface of the substrate across substantially the entire upper surface of the substrate.
    Type: Grant
    Filed: May 14, 1997
    Date of Patent: April 3, 2001
    Assignee: Applied Materials, Inc.
    Inventors: Yoichiro Tanaka, Liubo Hong, Yuichi Wada
  • Patent number: 6197167
    Abstract: The invention provides a method for depositing a metal film on a substrate, comprising generating a high density plasma in a chamber, sputtering metal particles from a target to the substrate, and applying a modulated radio frequency (RF) bias to the substrate during deposition. Another aspect of the invention provides an apparatus for depositing a metal film on a substrate comprising a high density plasma physical vapor deposition (HDP PVD) chamber and a controller to modulate a RF bias power applied to a substrate in the chamber.
    Type: Grant
    Filed: October 12, 1999
    Date of Patent: March 6, 2001
    Assignee: Applied Materials, Inc.
    Inventor: Yoichiro Tanaka
  • Patent number: 6170323
    Abstract: A vehicle meter self-diagnosis apparatus includes cross coil movements 11, 13, 15, and 17, drivers 10, 12, 14, 16, and 18, a driver control circuit 20, a ROM 22 into which indication adjustment information of the cross coil movements 11, 13, 15, and 17 is written, a CPU 8, and a self-diagnosis control circuit section 30 being started by a reset switch 32 for driving the drivers 10, 12, 14, 16, and 18 and diagnosing the cross coil movements 11, 13, 15, and 17.
    Type: Grant
    Filed: July 29, 1997
    Date of Patent: January 9, 2001
    Assignees: Kansei Corporation, Nissan Motor Co., Ltd.
    Inventors: Akihiro Enomoto, Masakazu Kobayashi, Yoichiro Tanaka
  • Patent number: 6126926
    Abstract: A whitening powder comprises the following ingredients:______________________________________ (A) trimethylsiloxylated silicic acid anhydride 0.1 to 7 wt. % having a specific area of at least 80 m.sup.2 /g and a hydrophobicization degree of at least 50% (B) polyhydric alcohol 5 to 40 wt. % (C) water 50 to 94 wt. % (D) whitening ingredient 0.01 to 5 wt. %. ______________________________________The whitening powder is substantially free of any powder coated with a fluorine compound, the weight ratio of the ingredient (B) to the ingredient (A) is at least 1, and the sum of the ingredient (B) and the ingredient (C) accounts for at least 80 wt. % of the whitening powder.
    Type: Grant
    Filed: January 15, 1998
    Date of Patent: October 3, 2000
    Assignee: Kose Corporation
    Inventors: Yoichiro Tanaka, Junichiro Egawa
  • Patent number: 6128166
    Abstract: According to this invention, there is provided a magnetic recording/reproducing system having a recording head for recording a signal in a magnetic recording medium along recording tracks having a predetermined track pitch and a reproducing head for reproducing the recorded signal. A relationship between a recording track width Tw of the recording head and a reproduction width Tr of the reproducing head is defined as Tr>Tw. When conditions g<(1500/Hc-Hc/4000.pi.+0.3)/(Hc/400.pi.-1/2) and g.gtoreq.(1500/Hc-Hc/4000.pi.+0.3-Tp+Tw)/(Hc/400.pi.-1/2) are satisfied, an erase region is formed between the recording tracks. In this case, the gap length of the recording head is represented by g [.mu.m], the recording track width is represented by Tw [.mu.m], the track pitch is represented by Tp [.mu.m], and the coercive force of the recording medium is represented by Hc [Oe].
    Type: Grant
    Filed: May 18, 1995
    Date of Patent: October 3, 2000
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yoichiro Tanaka, Norio Nakamura, Kazunori Moriya, Yuji Kubota, Takashi Hikosaka
  • Patent number: 6088181
    Abstract: A magnetic recording/reproducing device comprises a recording head for magnetically recording a signal on a magnetic recording medium along a predetermined track, and a reproducing head member including a spin valve typed magnetoresistive element and bias magnetic applying means, associated with the spin valve typed magnetoresistive element, for applying a bias magnetic field to the spin valve typed magnetoresistive element, the reproducing head member for changing a sensitivity distribution in a track width direction based on a distance between the reproducing head and the recording head, and an angle difference between the direction of the reproducing head and the extending direction of the track.
    Type: Grant
    Filed: May 29, 1997
    Date of Patent: July 11, 2000
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Yoichiro Tanaka
  • Patent number: 5995341
    Abstract: A magnetic disk drive has a magnetic head for recording or reproducing information on or from a magnetic recording medium. The magnetic recording medium includes a magnetic recording layer for information recording which has magnetic anisotropy in a direction perpendicular to a surface of the recording medium, a soft magnetic under layer under the magnetic recording layer and having soft magnetic properties, and a non-magnetic substrate. The magnetic disk drive records a signal with a skew angle on at least some tracks. A main pole has a size satisfying pL<(tP-tW cos .theta.)/sin .theta., where pL is a width of an end face of the main pole in a traveling direction, tW is a track width of the end face of the main pole, tP is a track pitch, and .theta. is a skew angle of a trailing edge of the main pole.
    Type: Grant
    Filed: October 13, 1998
    Date of Patent: November 30, 1999
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tsutomu Tanaka, Tomoko Taguchi, Yoichiro Tanaka
  • Patent number: 5981054
    Abstract: A magnetic recording medium comprising a substrate and a magnetic film formed on the substrate, the magnetic film including magnetic crystal grains in a non-magnetic matrix and satisfying the condition given below:d.sup.2 .multidot.t.multidot.Ir/(v.multidot.Isb).gtoreq.0.75wheret: a thickness of the magnetic film;Ir: a remanent magnetization moment of the magnetic film;d: an average particle size of the magnetic crystal grains in an intra-film direction of the magnetic film; andv.multidot.Isb: an activated magnetization moment of the magnetic film.
    Type: Grant
    Filed: July 21, 1997
    Date of Patent: November 9, 1999
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takashi Hikosaka, Tsutomu Tanaka, Yoichiro Tanaka, Katsutaro Ichihara, Keiichiro Yusu, Akira Kikitsu
  • Patent number: 5976327
    Abstract: The invention provides a method for depositing a metal film on a substrate, comprising generating a high density plasma in a chamber, sputtering metal particles from a target to the substrate, and applying a modulated radio frequency (RF) bias to the substrate during deposition. Another aspect of the invention provides an apparatus for depositing a metal film on a substrate comprising a high density plasma physical vapor deposition (HDP PVD) chamber and a controller to modulate a RF bias power applied to a substrate in the chamber.
    Type: Grant
    Filed: December 12, 1997
    Date of Patent: November 2, 1999
    Assignee: Applied Materials, Inc.
    Inventor: Yoichiro Tanaka
  • Patent number: 5949600
    Abstract: A magnetic recording and reproducing apparatus, including a probe made of a ferromagnetic film movable relative to a magnetic recording medium while having a distal end facing the magnetic recording medium; a head section having a recording element for recording a signal on the magnetic recording medium and a reproducing element including at least a probe for reproducing a signal recording on the magnetic recording medium; and a head slider for mounting the head section.
    Type: Grant
    Filed: September 6, 1996
    Date of Patent: September 7, 1999
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Junichi Akiyama, Yoichiro Tanaka
  • Patent number: 5942342
    Abstract: A magnetic recording apparatus comprising a perpendicular recording medium, a recording head for perpendicular magnetization the perpendicular magnetization film of the recording medium, to thereby recording signals on the recording medium, and a reproducing head of magnetoresistance type for reading signals from the recording medium. The medium comprises a substrate, an underlayer formed on the substrate, and a perpendicular magnetization film formed on the substrate and having a crystal phase of a CoPt-based alloy and a compound phase of material selected from the group consisting of Co oxide, Co nitride and Co carbide.
    Type: Grant
    Filed: October 27, 1997
    Date of Patent: August 24, 1999
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takashi Hikosaka, Yoichiro Tanaka, Junichi Akiyama
  • Patent number: 5920447
    Abstract: A magnetic multi-head unit includes: a specific magnetic head formed so that a pair of magnetic yokes face each other on the same plane via a magnetic gap inclined by a predetermined azimuth angle; and a magnetic head which is adjacent to the specific magnetic head and which is formed so that a pair of magnetic yokes face each other on a plane different from the plane of the specific magnetic head via a magnetic gap inclined by the azimuth angle. The specific magnetic head and the adjacent magnetic head are laminated so as to form a plurality of layers while being shifted from each other in directions in which tracks on a magnetic disk extend.
    Type: Grant
    Filed: March 14, 1997
    Date of Patent: July 6, 1999
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiromi Sakata, Hiroaki Yoda, Tomomi Funayama, Kohichi Tateyama, Tadahiko Kobayashi, Shigeru Takekado, Yoichiro Tanaka
  • Patent number: 5854727
    Abstract: A ratio tW/pL of a track width tW to a width pL of an end face, in a traveling direction, of a main pole which performs recording or reproduction on or from the magnetic recording layer of a medium, and a saturation magnetic flux density Bs (T: tesla) of a magnetic material constituting the main pole satisfy:(A.sub.1 .times.Bs+B.sub.1).sup.2 +C.sub.1 .ltoreq.tW/pL.ltoreq.(A.sub.2 .times.Bs+B.sub.2).sup.2 +C.sub.2for A.sub.1 =4.3.times..delta.+0.4, B.sub.1 =-16.2.times..delta.-0.3, C.sub.1 =2.2.times..delta.+0.3, A.sub.2 =378.times..delta..sup.2 -66.times..delta.+4.2, B.sub.2 =264.times..delta..sup.2 -43.times..delta.+2.1, and C.sub.2 =9.times..delta.-2.5 where .delta.(.mu.m) is a distance from the end face of the main pole to the soft magnetic under layer.
    Type: Grant
    Filed: July 16, 1997
    Date of Patent: December 29, 1998
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tsutomu Tanaka, Tomoko Taguchi, Yoichiro Tanaka
  • Patent number: 5824197
    Abstract: A target shield having a concave, curved surface away from a target in a physical vapor deposition chamber spaced so that the number of magnetic field lines that intersect said shield are reduced, results in improved vertical directionality of the sputtered material. High aspect ratio openings in a substrate can be filled at low pressures, e.g., 3 millitorr and lower, using this shield.
    Type: Grant
    Filed: June 5, 1996
    Date of Patent: October 20, 1998
    Assignee: Applied Materials, Inc.
    Inventor: Yoichiro Tanaka