Patents by Inventor Dean Craig Humphrey

Dean Craig Humphrey 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).

  • Pupil imaging reticle for photo steppers
    Patent number: 5973771
    Abstract: The invention relates to the evaluation of the pupil illumination profile in a projection lithography system using an imaging reticle featuring a plurality of holes of few microns in diameter. The imaging reticle is placed at the lens object plane and a photoresist coated substrate is exposed in a defocused position from the lithographic image plane. The image reticle has a plurality of identical holes that are regularly spaced at predetermined distances for a more detailed evaluation of the effective pupil illumination across the entire exposure field.
    Type: Grant
    Filed: March 26, 1997
    Date of Patent: October 26, 1999
    Assignee: International business Machines Corporation
    Inventors: Michael Straight Hibbs, Dean Craig Humphrey, Grant Neven Pealer, III, Barbara Bates Peck