International Business Machines Corporation

Alexander D Lopata

Anthony F Scaduto

Joseph F Shepard

George A Kaplita

Nicholas J Giammarco

Alexander Gimpelson

Christopher F Lyons

Ming-Fea Chow

Robert C McIntosh

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.

Mask using lithographic image size reduction

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.

Lithographic image size reduction

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.

Method for dose calculation of photolithography projection printers

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Fishkill, NY, United States of America

Alexander D Lopata