Patents by Inventor Clifford J. Hamel

Clifford J. Hamel 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).

  • Methods of simultaneous contact and metal lithography patterning
    Patent number: 4377633
    Abstract: This describes different methods of using a single photoresist layer to define both metal contact vias and metal lift-off areas on semiconductor integrated circuits. The methods use positive photoresist containing a small amount of base such as imidazole to provide a lift-off overhang when the resist is exposed and developed to provide a reversal image.
    Type: Grant
    Filed: August 24, 1981
    Date of Patent: March 22, 1983
    Assignee: International Business Machines Corporation
    Inventors: Karen M. Abrahamovich, Clifford J. Hamel, Edward H. Payne, Dean R. Weed