Patents by Inventor Sandra S. Zheng

Sandra S. Zheng 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).

  • Image displacement test reticle for measuring aberration characteristics of projection optics
    Patent number: 6396569
    Abstract: A method for testing the image displacement of a reticle following a change in illumination comprising the steps of taking a first image displacement measurement with a test reticle (110) having a variable linewidth (L) and a variable pitch size (s) on an image displacement mark (30, 40, 50, 60, 70, 80, 90, 100), changing the illumination conditions of the photolithographic equipment and taking a second image displacement measurement with the test reticle (110) to determine an image displacement offset due to changes in illumination, is disclosed.
    Type: Grant
    Filed: January 29, 2001
    Date of Patent: May 28, 2002
    Assignee: Texas Instruments Incorporated
    Inventors: Sandra S. Zheng, Cindy Pan
  • Image displacement test reticle for measuring aberration characteristics of projection optics
    Publication number: 20010017693
    Abstract: A method for testing the image displacement of a reticle following a change in illumination comprising the steps of taking a first image displacement measurement with a test reticle (110) having a variable linewidth (L) and a variable pitch size (s) on an image displacement mark (30, 40, 50, 60, 70, 80, 90, 100), changing the illumination conditions of the photolithographic equipment and taking a second image displacement measurement with the test reticle (110) to determine an image displacement offset due to changes in illumination, is disclosed.
    Type: Application
    Filed: January 29, 2001
    Publication date: August 30, 2001
    Inventors: Sandra S. Zheng, Cindy Pan