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:
Apr. 10, 2001
Filed:
Oct. 07, 1998
Orest Bula, Shelburne, VT (US);
Daniel Cole, Jericho, VT (US);
Edward Conrad, Jeffersonville, VT (US);
Ning Lu, Essex Junction, VT (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A proximity correction serif design methodology is described that provides improved inner and outer corner rounding, line end shortening, as well as improvements in more general undesirable two-dimensional shape distortions introduced into the lithographic printing process due to proximity effects. Using this method, exact solutions are shown for the specialized cases of either coherent or incoherent illumination exposing a hypothetical resist that develops via a simple diffusion like mechanism. The basis of this method for predicting the positions and shapes of serifs is tied to the need to increase the components of high spatial frequency that are essentially lost due to diffraction, diffusion, dissolution, and etching related effects. The correct amount to increase the spatial components is determined in the coordinate space and makes use of an empirical characterization of these physical factors.