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.
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