Patents by Inventor Douglas E. Lund

Douglas E. Lund 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: 5791969
    Abstract: A method of automatically polishing a semiconductor wafer having a substrate and a surface film. A wafer mounting device, which may include a vacuum chuck, holds the semiconductor wafer without requiring that the wafer have a central aperture. The mounting device and wafer are moved with an orbit-within-an-orbit motion while a tape transport mechanism applies an abrasive polishing tape to the surface film of the moving wafer to polish one surface of the wafer to a flatness of less than two microns. The polishing tape passes arcuately around a roller and passes between the roller and the surface film and contacts the surface film in a line running across the width of the tape. The system determines the thickness of the wafer surface film during the polishing process with a real time measurement device such as an effipsometer, or by determining a work-performed factor and calculating an estimated film thickness from the work-performed factor.
    Type: Grant
    Filed: February 13, 1997
    Date of Patent: August 11, 1998
    Inventor: Douglas E. Lund
  • Patent number: 5643044
    Abstract: A system and method for chemically and mechanically polishing a semiconductor wafer having a substrate and a surface film. A wafer mounting device, which may include a vacuum chuck, holds the semiconductor wafer without requiring that the wafer have a central aperture. The mounting device and wafer are moved with an orbit-within-an-orbit motion while a tape transport mechanism applies an abrasive polishing tape to the surface film of the moving wafer to polish one surface of the wafer to a flatness of less than two microns. The system determines the thickness of the wafer surface film during the polishing process with a real time measurement device such as an ellipsometer, or by determining a work-performed factor and calculating an estimated film thickness from the work-performed factor. Finally, the system automatically controls the polishing process to stop polishing the semiconductor wafer when the wafer surface film achieves a predefined planarization.
    Type: Grant
    Filed: November 1, 1994
    Date of Patent: July 1, 1997
    Inventor: Douglas E. Lund