Patents Represented by Attorney, Agent or Law Firm Stephen B. Ackelman
  • Patent number: 6821717
    Abstract: As the recording density of magnetic disk drives approaches 100 Gbits/in2, write track lengths of about 0.10 microns will be required. This cannot be accomplished using conventional photolithography. The present invention solves this problem by first forming on the bottom pole of the write head a cavity in a layer of photoresist, using conventional means. A seed layer of non-magnetic material is electrolessly laid down, following which a second layer of photoresist is deposited and patterned to form a second cavity that symmetrically surrounds the first one, thereby forming a mold around it. Ferromagnetic metal is then electro-deposited in this mold to form the top magnetic pole. Following the removal of all photoresist and a brief selective etch of the bottom pole, an extremely narrow write head is obtained.
    Type: Grant
    Filed: August 2, 2002
    Date of Patent: November 23, 2004
    Assignee: Headway Technologies, Inc.
    Inventors: Charles C. Lin, Kochan Ju, Jeiwei Chang