Patent ID: 6628370
Filing Date: 2003-09-30
Classification: G03F

Abstract:
A method of detecting variations in printed line widths formed on a photosensitive substrate from corresponding line widths on a reticle and compensating for the detected variations in printed line-widths in a photolithographic process comprising the steps of:exposing a test photosensitive substrate with the image of a reticle through a projection optic; processing the test photosensitive substrate forming a test printed substrate; identifying spatial locations on the test printed substrate having variations in printed line widths from those on the reticle being reproduced; mapping the spatial location and variance of the printed line widths different from those on the reticle being reproduced on the printed substrate; determining a required illumination property needed at each of the spatial locations on the test printed substrate necessary to compensate for the variations in printed line widths from those on the reticle being reproduced; modifying the electromagnetic radiation provided to the reticle at a location corresponding to each of the spatial locations on the test printed substrate to provide the required illumination property needed at each of the spatial locations on the printed substrate necessary to compensate for the variations in printed line widths from those of the reticle being reproduced; exposing a production photosensitive substrate at each of the spatial locations with electromagnetic radiation resulting from the step of modifying the electromagnetic radiation; and processing the production photosensitive substrate forming a compensated production printed substrate, whereby variations in line width on the compensated production printed substrate are reduced and more closely conform to corresponding line widths on the reticle.