Patents by Inventor Koichiro Yamazki

Koichiro Yamazki 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: 5250338
    Abstract: A magnetic recording medium which comprises a non-ferromagnetic substrate having two types of defects or irregularities formed thereon along a circumferential direction with different center line average roughnesses, on which a non-ferromagnetic metal film and a Co alloy ferromagnetic film are formed by sputtering in this order. The ferromagnetic film has such a crystal structure that a (200) plane is parallel to the surface of the substrate and a <011> orientation is toward a circumferential direction. Thus, the C axis of the ferromagnetic film is oriented toward the circumferential direction of the substrate. A method for fabricating the magnetic recording medium is also described wherein the distance between the substrate and the respective targets for the non-ferromagnetic metal film and the Cr alloy ferromagnetic film is set within a mean free path of sputtered particles and the substrate is heated to a temperature of from 150.degree. to 300.degree. C. when these films are formed by sputtering.
    Type: Grant
    Filed: November 16, 1989
    Date of Patent: October 5, 1993
    Assignee: Victor Company of Japan, Ltd.
    Inventors: Masaki Shintani, Kanji Takashima, Koichiro Yamazki, Toshio Kato