Abstract: A method of determining a feature-forming variant, such as focus or exposure, for a lithographic system or the like includes Fourier processing that extracts a figure of merit. In a preferred embodiment, the lithographic system fabricates a series of formations of a single pattern. An optical image of each exposure is formed. A Fourier power spectrum is determined for each optical image. An angular power function is extracted from each power spectrum by quantifying optical power along lines originating at various angles from an origin of the power spectrum. With regard to axes of maximum power, the distribution of on-axes and off-axes power is quantified for each angular power function. An optimum for the lithographic system is determined based upon the data extracted from the angular power functions.

Abstract: Reticle data used to form a reticle pattern is modified to substantially compensate for proximity effects resulting from the diffraction of light by opaque portions of the reticle pattern.The reticle pattern is thus modified so that the exposed pattern on the wafer results in a desired pattern, wherein isolated features and features in a dense pattern of features formed on the wafer will be identical and have predictable characteristics.