Patents by Inventor Steven D. Downey

Steven D. Downey 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).

  • Semiconductor etching apparatus with magnetic array and vertical shield
    Patent number: 4632719
    Abstract: In an apparatus for etching a large semiconductor wafer the etch rate and uniformity of etching at the edges is improved by using an array of magnets behind the collector plate to form a double ring of plasma and using a grounded shield ring with perforations to pass gases. The shield ring extends both above and below the surface of the wafer being etched.
    Type: Grant
    Filed: September 18, 1985
    Date of Patent: December 30, 1986
    Assignee: Varian Associates, Inc.
    Inventors: Robert Chow, Steven D. Downey