Patents by Inventor Alexander D. Lopata

Alexander D. Lopata 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: 4871630
    Abstract: Disclosed is a process for reducing lithographic image size for integrated circuit manufacture. A mask of photosensitive material having an opening of a minimum size dictated by the limits of lithography is formed on a substrate. Reduction in the image size is achieved by establishing sidewalls to the interior vertical surfaces of the opening by depositing a conformal layer, followed by anisotropic etching. The dimension of the opening is reduced by the combined thickness of the two opposite insulator sidewalls.In a specific direct application of the disclosed process, a photomask/stencil having a pattern of openings of a minimum size smaller than possible by lighography, per se, is formed.
    Type: Grant
    Filed: July 31, 1987
    Date of Patent: October 3, 1989
    Assignee: International Business Machines Corporation
    Inventors: Nicholas J. Giammarco, Alexander Gimpelson, George A. Kaplita, Alexander D. Lopata, Anthony F. Scaduto, Joseph F. Shepard
  • Patent number: 4707218
    Abstract: Disclosed is a process for reducing lithographic image size for integrated circuit manufacture. A mask of photosensitive material having an opening of a minimum size dictated by the limits of lithography is formed on a substrate. Reduction in the image size is achieved by establishing sidewalls to the interior vertical surfaces of the opening by depositing a conformal layer, followed by anisotropic etching. The dimension of the opening is reduced by the combined thickness of the two opposite insulator sidewalls.In a specific direct application of the disclosed process, a photomask/stencil having a pattern of openings of a minimum size smaller than possible by lithography, per se, is formed.
    Type: Grant
    Filed: October 28, 1986
    Date of Patent: November 17, 1987
    Assignee: International Business Machines Corporation
    Inventors: Nicholas J. Giammarco, Alexander Gimpelson, George A. Kaplita, Alexander D. Lopata, Anthony F. Scaduto, Joseph F. Shepard
  • Patent number: 4474864
    Abstract: A process for setting the exposure speed of photolithography instruments is described, using a method of dosimetry based on photoactive compound bleaching of photoresist. A curve of light absorbance to exposure speed and a calibration curve of light absorbance to dose are determined for a photoresist. The exposure speed for any desired degree of resist bleaching can be set using the first curve, and the exposure speed for a predetermined dosage can be set by determining the common light absorbance value on the exposure speed and dosage curves.
    Type: Grant
    Filed: July 8, 1983
    Date of Patent: October 2, 1984
    Assignee: International Business Machines Corporation
    Inventors: Ming-Fea Chow, Alexander D. Lopata, Christopher F. Lyons, Robert C. McIntosh, Anthony F. Scaduto