Patents by Inventor Eiki Narumi

Eiki Narumi 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: 6416677
    Abstract: As the read capabilities of magnetic disk systems improve due to advanced GMR heads, it becomes necessary to correspondingly reduce the area of recorded data. This requires a narrowing of the stitched sub-pole at the write gap. This has proved difficult for pole widths less than about 0.4 microns because of problems in filling the mold. In the present invention this is overcome by introducing a layer of PMGI (polydimethylglutarimide) between the planarized positive photoresist layer that comprises the mold and the non-magnetic write gap layer on which the mold rests. This greatly facilitates formation of a high aspect ratio hole with a clean flat bottom and essentially vertical sides as well as the subsequent removal of the photoresist after said hole has been filled through electroplating to form a stitched sub-pole.
    Type: Grant
    Filed: June 5, 2000
    Date of Patent: July 9, 2002
    Assignee: Headway Technologies, Inc.
    Inventors: Hsiang-Yi Wei, Yi-Ting Yao, Eiki Narumi, Chyu-Jiuh Torng, Cherng-Chyi Han