MINUPROX - An Advanced Proximity Correction Technique for the IBM El-2 Electron Beam Tool

MINUPROX - (Minimum Neighborhood Proximity Correction) is a novel approach to proximity correction used with the IBM EL-2 E-Beam direct exposure tool. Based on earlier work by M. Parikh, it differs from his approach primarily by only correcting those shapes that form the edge definition o the image. Reflecting experimental observations that the dose assignment to the edges of the image is much more critical than the assignment made to the interior, MINUPROX separates the edges from the interior of the image and only applies proximity corrections to the edges. The interior is assigned a predetermined dose, thus saving considerable computation time otherwise spent on its correction. Correction of the edges is performed on a neighborhood basis, thus ensuring that similar shapes in similar environments will be assigned similar doses. Both positive and negative images are handled with equal efficiency, and the lower range of the tool is extended down to geometries of 1.0 micro-meter.