Patents by Inventor Yukimasa Okada

Yukimasa Okada 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: 20140177093
    Abstract: A magnetic head according to one embodiment includes a read sensor adapted for sensing an external magnetic field; an upper magnetic shield positioned above the read sensor along an air bearing surface (ABS) of the read sensor; a lower magnetic shield positioned below the read sensor along the ABS of the read sensor; a rear insulating layer positioned on a rear side of the read sensor, the rear side being on an opposite side of the read sensor as the ABS of the read sensor; and a soft magnetic layer positioned near the rear side of the read sensor opposite the ABS of the read sensor, wherein the rear insulating layer is positioned between the soft magnetic layer and the read sensor, and wherein the rear insulating layer is positioned between the soft magnetic layer and the lower magnetic shield.
    Type: Application
    Filed: December 21, 2012
    Publication date: June 26, 2014
    Applicant: HGST NETHERLANDS B.V.
    Inventors: Katsumi Hoshino, Kouji Kataoka, Takashi Wagatsuma, Yukimasa Okada
  • Patent number: 8760787
    Abstract: In one embodiment, a method includes forming a conducting material above an insulating film, applying a mask to portions of the conducting material in a shape of a TFC structure, removing exposed portions of the conducting material to form the TFC structure, depositing an insulating film above the TFC structure, and planarizing the insulating film to form a planar upper surface of the insulating film. In another embodiment, a magnetic head includes a TFC structure positioned between insulating films and a magnetic element positioned above the TFC structure, the TFC structure configured for providing localized thermal protrusion of the magnetic head on a media facing surface thereof, wherein an upper surface of an upper of the insulating films is planar, the magnetic element includes at least one of a main magnetic pole and a read sensor, and the TFC structure is configured for providing thermal protrusion of the magnetic element.
    Type: Grant
    Filed: December 2, 2011
    Date of Patent: June 24, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Takashi Wagatsuma, Yukimasa Okada, Ichiro Oodake, Atsushi Kato
  • Publication number: 20130141813
    Abstract: In one embodiment, a method includes forming a conducting material above an insulating film, applying a mask to portions of the conducting material in a shape of a TFC structure, removing exposed portions of the conducting material to form the TFC structure, depositing an insulating film above the TFC structure, and planarizing the insulating film to form a planar upper surface of the insulating film. In another embodiment, a magnetic head includes a TFC structure positioned between insulating films and a magnetic element positioned above the TFC structure, the TFC structure configured for providing localized thermal protrusion of the magnetic head on a media facing surface thereof, wherein an upper surface of an upper of the insulating films is planar, the magnetic element includes at least one of a main magnetic pole and a read sensor, and the TFC structure is configured for providing thermal protrusion of the magnetic element.
    Type: Application
    Filed: December 2, 2011
    Publication date: June 6, 2013
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Takashi Wagatsuma, Yukimasa Okada, Ichiro Oodake, Atsushi Kato
  • Publication number: 20130141814
    Abstract: In one embodiment, a magnetic disk device includes a magnetic disk medium, at least one magnetic head having at least one of: a magnetic read element adapted for reading data from the magnetic disk medium and a magnetic write element adapted for writing data to the magnetic disk medium, and a heating element adapted for generating heat upon application of a voltage/current thereto, wherein the heating element is positioned on, near, or within the magnetic head, a drive mechanism for passing the magnetic disk medium over the at least one magnetic head, and a controller electrically coupled to the at least one magnetic head for controlling operation of the at least one magnetic head, wherein the controller is configured to retract the at least one magnetic head from a flying state above the magnetic disk medium and apply the voltage/current to the heating element while the magnetic head is retracted.
    Type: Application
    Filed: December 2, 2011
    Publication date: June 6, 2013
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Yukimasa Okada, Katsumi Hoshino, Koji Kataoka, Takashi Wagatsuma
  • Patent number: 7957109
    Abstract: A tunnel magnetoresistance effect magnetic head having between magnetic shield layers, an antiferromagnetic layer, a pinned layer which has the direction of magnetization pinned by exchange coupling with the antiferromagnetic layer, an insulating layer, and a free layer whose direction of magnetization rotates relatively to external magnetic fields, wherein the antiferromagnetic layer is of an antiferromagnetic substance composed mainly of IrMn, the pinned layer is made up of a first pinned layer of CoFe alloy in contact with the antiferromagnetic layer and a second pinned layer of CoFeB alloy which is antiferromagnetically coupled with the first pinned layer, and the first and second pinned layers have the amount of magnetization such that the difference M1?M2 is in the range of 0<M2?M1<0.5 (nm·T) and also have the magnetostriction constants such that the difference |?1??2| is no larger than 5.0×10?6.
    Type: Grant
    Filed: September 11, 2007
    Date of Patent: June 7, 2011
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Naoki Koyama, Koichi Nishioka, Kouji Okazaki, Shuichi Kojima, Azusa Hori, Satoshi Shigematsu, Yukimasa Okada
  • Publication number: 20080074803
    Abstract: Embodiments of the present invention prevent a pinned layer from suffering magnetization reversal by external stress in a magnetic head of magnetoresistance effect type which has a synthetic ferri-magnetic pinned layer structure with an antiferromagnetic layer of IrMnCr. According to one embodiment, a read element of a magnetoresistive head is made up of a antiferromagnetic layer, a first pinned layer, an antiferromagnetically coupled layer 4, a second pinned layer, and a free layer, which are stacked one over another. The first and second pinned layers and have a composition of Co75Fe25 and Co95Fe5, respectively, and a thickness of 18 ? (3.5 nm·T) and 21 ? (3.9 nm·T), respectively, so as to reduce the difference in anisotropic energy between the first pinned layer in contact with the antiferromagnetic layer and the second pinned layer in contact with the nonmagnetic conductive layer.
    Type: Application
    Filed: September 11, 2007
    Publication date: March 27, 2008
    Applicant: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Naoki Koyama, Koichi Nishioka, Kouji Okazaki, Shuichi Kojima, Azusa Hori, Satoshi Shigematsu, Yukimasa Okada