Patents by Inventor Robert A. Geshner

Robert A. Geshner 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).

  • Visual defect inspection of masks
    Patent number: 4432641
    Abstract: An optical system and method for direct human eye visual inspection of specimens of photoresist coated masks for defects as small as 2 .mu.m. The specimens are uniformly illuminated with a partially coherent sodium light that has very high illuminance and constrast levels. The system consists of a high pressure (1-1.5 atmosphere) sodium lamp source projected onto the specimen by a Kohler-type illumination system.
    Type: Grant
    Filed: October 16, 1981
    Date of Patent: February 21, 1984
    Assignee: RCA Corporation
    Inventors: Fausto Caprari, Robert A. Geshner
  • Method for removing defects from chromium and chromium oxide photomasks
    Patent number: 4105468
    Abstract: Removal of selected, isolated defects comprised of excess chromium (Cr) or chromium oxide (Cr.sub.2 O.sub.3) from photomasks comprises contacting at least the defect area by a suitable acid and initiating the etch of the defect area by contacting the defect area with a metal probe made from a suitable material. Excess chromium or chromium oxide areas may be isolated by using a laser to separate the areas from areas which are to remain.
    Type: Grant
    Filed: June 9, 1977
    Date of Patent: August 8, 1978
    Assignee: RCA Corp.
    Inventors: Robert A. Geshner, Joseph Mitchell, Jr.