Patents by Inventor Naruhisa Nagata

Naruhisa Nagata 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: 20100086808
    Abstract: A method of forming a protective film of a magnetic recording medium is provided that achieves a good bonding characteristic with a lubricant film and at the same time, suppressing adhesion of contamination gases, to attain a reduced thickness of the magnetic recording medium. The method includes forming a protective film on a lamination including a substrate and a metallic film layer formed on the substrate, by means of a plasma CVD method using a raw material of a hydrocarbon gas, and performing a surface treatment on the protective film. The surface treatment includes a plasma treatment with argon gas, and a plasma treatment with a gas containing at least nitrogen gas.
    Type: Application
    Filed: August 27, 2009
    Publication date: April 8, 2010
    Applicant: FUJI ELECTRIC DEVICE TECHNOLOGY CO., LTD.
    Inventor: Naruhisa NAGATA
  • Publication number: 20090291326
    Abstract: A protective film is disclosed that is mainly composed of a tetrahedral amorphous carbon (ta-C film) that is denser than a DLC film formed by a plasma CVD method and containing aggregate particles so reduced as to a necessary and sufficient level, to provide a method of manufacturing such a protective film, and to provide a magnetic recording medium comprising such a protective film. The film is mainly composed of a ta-C film formed by a filtered cathodic arc method using a cathode target of glass state carbon. A magnetic recording medium is disclosed which includes a substrate, a magnetic recording layer, and the protective film mainly composed of a ta-C film.
    Type: Application
    Filed: May 22, 2009
    Publication date: November 26, 2009
    Applicant: Fuji Electric Device Technology Co., Ltd.
    Inventor: Naruhisa NAGATA
  • Publication number: 20090075121
    Abstract: An apparatus and method for forming a carbon protective layer on a substrate using a plasma CVD method allows a more uniform in-plane distribution of the carbon protective layer thickness. The apparatus includes an annular anode that generates a plasma beam and a disk-shaped shield disposed between the anode and the substrate. The anode, the shield, and the substrate are concentrically arranged so that a straight line connecting the centers of the anode and the substrate is perpendicular to the deposition surface of the substrate where the carbon protective layer is to be formed. The center of the shield is also on the straight line.
    Type: Application
    Filed: September 7, 2008
    Publication date: March 19, 2009
    Applicant: FUJI ELECTRIC DEVICE TECHNOLOGY CO., LTD.
    Inventor: Naruhisa NAGATA
  • Patent number: 7354629
    Abstract: A method of forming a protective film that restrains gas adsorption while preserving durability and corrosion resistance of a plasma CVD carbon film is disclosed. A protective film of a slide-resistant member is deposited by means of a plasma CVD method using a raw material of hydrocarbon gas, wherein a bias voltage higher than ?500 V is applied to the slide-resistant member in an initial stage of depositing the protective film, and a bias voltage of ?500 V or lower is applied in a final stage of deposition. A proportion of time duration of the final stage is preferably at most 25% of the total time for depositing the protective film. A magnetic recording medium comprising a magnetic recording layer and a protective film formed by the method also is disclosed.
    Type: Grant
    Filed: August 10, 2006
    Date of Patent: April 8, 2008
    Assignee: Fuji Electric Device Technology Co., Ltd.
    Inventor: Naruhisa Nagata
  • Publication number: 20070037014
    Abstract: A method of forming a protective film that restrains gas adsorption while preserving durability and corrosion resistance of a plasma CVD carbon film is disclosed. A protective film of a slide-resistant member is deposited by means of a plasma CVD method using a raw material of hydrocarbon gas, wherein a bias voltage higher than ?500 V is applied to the slide-resistant member in an initial stage of depositing the protective film, and a bias voltage of ?500 V or lower is applied in a final stage of deposition. A proportion of time duration of the final stage is preferably at most 25% of the total time for depositing the protective film. A magnetic recording medium comprising a magnetic recording layer and a protective film formed by the method also is disclosed.
    Type: Application
    Filed: August 10, 2006
    Publication date: February 15, 2007
    Applicant: FUJI ELECTRIC DEVICE TECHNOLOGY CO., LTD.
    Inventor: Naruhisa Nagata
  • Publication number: 20050045472
    Abstract: In a vacuum arc evaporation apparatus, to stably maintain vacuum arc discharge at an arc source when depositing a cathode material on a substrate, namely a magnetic recording medium, an ungrounded anode of a coil-type tube is placed inside an arc source discharge vacuum chamber. A DC arc power supply is connected between the cathode and the anode to cause an arc current to flow in the anode to generate a first magnetic field in one direction, from the cathode toward the anode. A second magnetic field is generated in the opposite direction, from the anode to the cathode by feeding a specified current to an external coil positioned around the discharge chamber. The external coil includes an around-cathode coil and an around-anode coil. The arc discharge can be started by operating a striker to carry out the deposition.
    Type: Application
    Filed: July 8, 2004
    Publication date: March 3, 2005
    Inventor: Naruhisa Nagata