Patents by Inventor Naoki Mukoyama

Naoki Mukoyama 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: 10605851
    Abstract: A printed wiring board includes: a laminated body that has a plurality of wiring layers laminated therein; a first through hole that electrically connects two or more wiring layers with each other; and a second through hole that has strength to expansion and contraction of the laminated body less than in the first through hole.
    Type: Grant
    Filed: June 16, 2017
    Date of Patent: March 31, 2020
    Assignee: FUJITSU LIMITED
    Inventors: Shigeo Iriguchi, Naoki Nakamura, Shigeru Sugino, Takahide Mukoyama, Ryo Kanai, Nobuo Taketomi, Kiyoyuki Hatanaka
  • Publication number: 20090059431
    Abstract: This head gimbals assembly has a head slider, a flexure, and a load beam. The head slider has a head element and slider-side connection terminals. The flexure has a free end, a fixed end, a slider mounting portion and suspension-side connection terminals connected to the slider-side connection terminals. The load beam fixes a fixed end of the flexure on the side opposite to a flexure surface on which the head slider is mounted a connecting portion for interconnecting the suspension-side connection terminals and the slider mounting portion has higher resiliency than other portion of the connecting portion. According to a suspension in the present embodiment, a head gimbals assembly can be easily manufactured without wastefully discarding the suspension even when the desired evaluation result is not obtained because of problems in the head characteristics and the floating surface of the head slider.
    Type: Application
    Filed: February 27, 2008
    Publication date: March 5, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Hiroaki Kushima, Toru Watanabe, Kenrou Yamamoto, Tetsuya Takahashi, Naoki Mukoyama
  • Publication number: 20080118778
    Abstract: A magnetoresistive reproducing head includes first and second free magnetic layers. A non-magnetic layer is provided between the first and second free magnetic layers. A bias applying layer having a single region applies a bias magnetic field in a direction perpendicular to the medium facing plane of the first free-magnetic layer and the second free-magnetic layer. An electrode is electrically connected to the first free-magnetic layer, the second free-magnetic layer, and the non-magnetic layer. In response to a magnetic field generated when a current is applied to the first free-magnetic layer, the second free-magnetic layer, and the non-magnetic layer in a direction perpendicular to the medium facing plane, magnetizations of the first free-magnetic and the second free-magnetic layer are tilted in opposite directions from a direction perpendicular to the medium facing plane.
    Type: Application
    Filed: November 5, 2007
    Publication date: May 22, 2008
    Applicant: Fujitsu Limited
    Inventors: Hideyuki Akimoto, Naoki Mukoyama, Jun Masuko
  • Publication number: 20080074808
    Abstract: A magnetoresistive element 11 is formed with inclusion of a free layer 12, a pinned layer 13, an antiferromagnetic layer 14 for pinning the pinned layer 13, an intermediate layer 15 provided between the free layer 12 and the pinned layer 13, and a ferromagnetic layer 16 for applying a longitudinal bias magnetic field to the free layer. After initial magnetization, characteristic evaluation is conducted for the magnetoresistive element 11. Intensity of longitudinal bias field is adjusted by magnetizing again in a direction different from that of the initial magnetization, if required, on the basis of the evaluation result.
    Type: Application
    Filed: February 26, 2007
    Publication date: March 27, 2008
    Inventors: Hideyuki Akimoto, Naoki Mukoyama
  • Patent number: 7197813
    Abstract: The magnetoresistance is measured for a magnetoresistive layered-structure, such as a spin valve film, prior to formation of an upper shield layer as well as patterning of a lower shield layer. The magnetic influence of the upper and lower shield layers can completely be eliminated during the measurement of the magnetoresistance. The magnetoresistive layered-structure is allowed to reliably receive the magnetic field over a wider range including a lower magnetic field range. It is accordingly possible to measure the magnetoresistance properly reflecting the magnetic characteristic of the magnetoresistive layered-structure. It is possible to find deficiency of a magnetoresistive read element at an earlier stage of the method.
    Type: Grant
    Filed: September 12, 2001
    Date of Patent: April 3, 2007
    Assignee: Fujitsu Limited
    Inventors: Naoki Mukoyama, Kenichiro Yamada, Hitoshi Kanai, Manabu Watanabe, Norikazu Ozaki, Kazuaki Satoh
  • Patent number: 6851179
    Abstract: The present invention provides a method for producing a magnetic head whose reproduction waveform has small distortions, and forming a hard magnetism layer for applying a bias magnetic field to a magnetoresistive element, which is a multilayer film including a fixed magnetic layer having magnetization fixed to a first direction and a free magnetic layer having an easy axis of magnetization that is directed to a second direction, is formed in an area including at least one of a front area in the first direction and a rear area in the first direction.
    Type: Grant
    Filed: December 19, 2000
    Date of Patent: February 8, 2005
    Assignee: Fujitsu Limited
    Inventors: Junichi Kane, Hitoshi Kanai, Kenji Noma, Naoki Mukoyama
  • Patent number: 6829122
    Abstract: A magnetic head of a magnetoresistance type is provided. The magnetic head comprises a magnetoresistance film, an underlying layer formed on each of both sides of the magnetoresistance film, and a magnetic-domain regulating film formed on the underlying layer so as to regulate a magnetic domain of a free magnetic layer in the magnetoresistance film. The underlying layer has a laminated structure of a tungsten-(W)-group metal layer formed on a tantalum-(Ta)-group metal layer. The underlying layer is formed so thick as to arrange the magnetic-domain regulating film at a position corresponding to the free magnetic layer.
    Type: Grant
    Filed: September 24, 2001
    Date of Patent: December 7, 2004
    Assignee: Fujitsu Limited
    Inventors: Kenichiro Yamada, Naoki Mukoyama, Hidehiko Suzuki, Hitoshi Kanai
  • Publication number: 20030128479
    Abstract: An object of the present invention is, in a magnetoresistive head having a magnetoresistive film that exhibits a change of resistance according to a direction of magnetization wherein information is reproduced from a magnetic recording medium by detecting the change of resistance of the magnetoresistive film, and an information reproduction apparatus that reproduces information from the magnetic recording medium by detecting the change of resistance of the magnetoresistive film, to provide a magnetoresistive head with heat generation being suppressed even if a current density of a sense current through a magnetoresistive film is high, and an information reproduction apparatus provided with such a magnetoresistive head. A height of a center portion of the magnetoresistive film is shorter than a height of end portions thereof, or a width of the end portion of the magnetoresistive film varies with height.
    Type: Application
    Filed: December 11, 2002
    Publication date: July 10, 2003
    Applicant: FUJITSU LIMITED
    Inventor: Naoki Mukoyama
  • Publication number: 20020138970
    Abstract: The magnetoresistance is measured for a magnetoresistive layered-structure, such as a spin valve film, prior to formation of an upper shield layer as well as patterning of a lower shield layer. The magnetic influence of the upper and lower shield layers can completely be eliminated during the measurement of the magnetoresistance. The magnetoresistive layered-structure is allowed to reliably receive the magnetic field over a wider range including a lower magnetic field range. It is accordingly possible to measure the magnetoresistance properly reflecting the magnetic characteristic of the magnetoresistive layered-structure. It is possible to find deficiency of a magnetoresistive read element at an earlier stage of the method.
    Type: Application
    Filed: September 12, 2001
    Publication date: October 3, 2002
    Applicant: FUJITSU LIMITED
    Inventors: Naoki Mukoyama, Kenichiro Yamada, Hitoshi Kanai, Manabu Watanabe, Norikazu Ozaki, Kazuaki Satoh
  • Publication number: 20020109948
    Abstract: A magnetic head of a magnetoresistance type is provided. The magnetic head comprises a magnetoresistance film, an underlying layer formed on each of both sides of the magnetoresistance film, and a magnetic-domain regulating film formed on the underlying layer so as to regulate a magnetic domain of a free magnetic layer in the magnetoresistance film. The underlying layer has a laminated structure of a tungsten-(W)-group metal layer formed on a tantalum-(Ta)-group metal layer. The underlying layer is formed so thick as to arrange the magnetic-domain regulating film at a position corresponding to the free magnetic layer.
    Type: Application
    Filed: September 24, 2001
    Publication date: August 15, 2002
    Applicant: FUJITSU LIMITED
    Inventors: Kenichiro Yamada, Naoki Mukoyama, Hidehiko Suzuki, Hitoshi Kanai
  • Patent number: 6400519
    Abstract: A spin valve magnetoresistive effect type element assessment device includes a head assaying device having a magnetic disk provided with an assaying track where magnetic information is recorded, an oscilloscope for receiving a reproducing signal from an SV head employing an SV element through an amplifier, and a PC for measuring a track profile, namely, data representing relative position dependency of an output from the SV head with respect to the assaying track by controlling the head assaying device and oscilloscope.
    Type: Grant
    Filed: January 31, 2001
    Date of Patent: June 4, 2002
    Assignee: Fujitsu Limited
    Inventor: Naoki Mukoyama
  • Publication number: 20020054463
    Abstract: A spin-valve magneto-resistive element is provided with a free magnetic layer having a first surface and a second surface opposite to the first surface, a first stacked structure including a first nonmagnetic metal layer, a first pinned magnetic layer and a first antiferromagnetic layer which are successively stacked on the first surface of the free magnetic layer, and a second stacked structure including a second nonmagnetic metal layer, a second pinned magnetic layer and a second antiferromagnetic layer which are successively stacked on the second surface of the free magnetic layer. A direction of an exchange coupled field between the first pinned magnetic layer and the free magnetic layer and a direction of an exchange coupled field between the second pinned magnetic layer and the free magnetic layer are antiparallel.
    Type: Application
    Filed: March 15, 2001
    Publication date: May 9, 2002
    Applicant: FUJITSU LIMITED
    Inventors: Naoki Mukoyama, Kenji Noma, Jongill Hong, Junichi Kane
  • Patent number: 6385018
    Abstract: The magnetoresistive read head comprises a hard magnetic bias layer formed along the end surface of a magnetoresistive layer or spin valve layer extending over the level plane. The tip end of the hard magnetic bias layer reaches or overlaps the top surface of the magnetoresistive layer. The overlap amount is measured from the tip end of the hard magnetic bias layer to the terminal end of the free magnetic layer. The overlap amount smaller than 0.282 &mgr;m serves to reduce Barkhausen noise appearing in the output from the magnetoresistive layer. In addition, when an inclination angle is set larger than 40° between the end surface and the level plane, a larger amount of hard magnetic bias layer is allowed to cover the top surface of the magnetoresistive layer.
    Type: Grant
    Filed: October 22, 1999
    Date of Patent: May 7, 2002
    Assignee: Fujitsu Limited
    Inventor: Naoki Mukoyama
  • Publication number: 20010052181
    Abstract: Provided is a method for producing a magnetic head whose reproduction waveform has small distortions.
    Type: Application
    Filed: December 19, 2000
    Publication date: December 20, 2001
    Applicant: FUJITSU LIMITED
    Inventors: Junichi Kane, Hitoshi Kanai, Kenji Noma, Naoki Mukoyama
  • Publication number: 20010004244
    Abstract: A spin valve magnetoresistive effect type element assessment device includes a head assaying device having a magnetic disk provided with an assaying track where magnetic information is recorded, an oscilloscope for receiving a reproducing signal from an SV head employing an SV element through an amplifier, and a PC for measuring a track profile, namely, data representing relative position dependency of an output from the SV head with respect to the assaying track by controlling the head assaying device and oscilloscope.
    Type: Application
    Filed: January 31, 2001
    Publication date: June 21, 2001
    Applicant: FUJITSU LIMITED
    Inventor: Naoki Mukoyama