Patents by Inventor Walter Torbert

Walter Torbert 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: 4918870
    Abstract: A polishing apparatus has a conventional carrier with a plurality of floating subcarriers. The benefits of single wafer polishing are achieved with the economies of multiple wafer polishing by adding the plurality of floating subcarriers to the conventional carrier. Each subcarrier has a single wafer adhered to its underside. Axial freedom is provided to duplicate the dynamics of single wafer polishing. The required axial freedom is obtained by axially loading each subcarrier via a mechanical spring or via pneumatic/hydraulic devices. In two variations, each subcarrier is also allowed auto-rotational freedom. In another two variations, the subcarriers are rotationally driven. In all variations, the wafers adhered to the floating subcarriers are substantially uniformly polished and the total indicated reading of the maximum deviation on the wafer surface is improved.
    Type: Grant
    Filed: May 16, 1986
    Date of Patent: April 24, 1990
    Assignee: Siltec Corporation
    Inventors: Walter Torbert, Kenneth C. Struven, Robert E. Lorenzini, Anthony C. Bonora