Patents by Inventor Steven D. Slonaker

Steven D. Slonaker 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).

  • Method to diagnose imperfections in illuminator of a lithographic tool
    Patent number: 6943882
    Abstract: A method for diagnosing a lithographic tool. The method includes developing digitalized images of at least one wafer pattern with different exposure doses and assembling the digitized images into a pupilgram. The at least one function is of a known illuminator behavior of the lithographic tool is modeled. The pupilgram is fitted to the modeled function to determine whether a behavior associated with the pupilgram is within predetermined limits of illuminator behavior to diagnosis imperfections in the illuminator behavior. One technique applied to the illuminator analysis consists of evaluating the dose transmitted (by direct calculation) by the lens for a given input pupilgram (or set of pupilgram basis functions), a given pattern size and pitch, and a defined lens NA, is described.
    Type: Grant
    Filed: December 19, 2002
    Date of Patent: September 13, 2005
    Assignee: NIKON Precision, Inc.
    Inventors: Stephen P. Renwick, Steven D. Slonaker
  • Method to diagnose imperfections in illuminator of a lithographic tool
    Publication number: 20040119957
    Abstract: A method for diagnosing a lithographic tool. The method includes developing digitalized images of at least one wafer pattern with different exposure doses and assembling the digitized images into a pupilgram. The at least one function is of a known illuminator behavior of the lithographic tool is modeled. The pupilgram is fitted to the modeled function to determine whether a behavior associated with the pupilgram is within predetermined limits of illuminator behavior to diagnosis imperfections in the illuminator behavior. One technique applied to the illuminator analysis consists of evaluating the dose transmitted (by direct calculation) by the lens for a given input pupilgram (or set of pupilgram basis functions), a given pattern size and pitch, and a defined lens NA, is described.
    Type: Application
    Filed: December 19, 2002
    Publication date: June 24, 2004
    Inventors: Stephen P. Renwick, Steven D. Slonaker