The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 07, 2002
Filed:
May. 19, 1998
Orest Bula, Shelburne, VT (US);
Daniel Cole, Jericho, VT (US);
Edward W. Conrad, Jeffersonville, VT (US);
Stephen E. Knight, Essex Junction, VT (US);
Robert K. Leidy, Burlington, VT (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Fine feature lithography is enhanced by selectively providing exposures to correct for effects such as foreshortening, corner rounding, nested to isolated print bias, feature size dependent bias, and other image biases in semiconductor processing. These results are achieved by increasing the local exposure dose in critical areas of specific images, such as line ends and corners. The general process incorporates techniques which tailor the exposure dose as a function of position to achieve the desired final image shape. The techniques include contrast enhancement layers (CEL), scanning optical beams, and exposures with different masks. In one embodiment the process of forming a pattern comprises the steps of providing a substrate having a photosensitive coating, exposing the center area of the pattern on the photosensitive coating with one mask, and exposing ends of the pattern on the photosensitive coating without exposing the center area with a second mask. The second exposure overlaps the first exposure and may extend beyond the pattern but the second dose is much lower than the first dose.