METHOD OF APPROXIMATING VALUE OF CRITICAL DIMENSION OF PATTERN FORMED BY PHOTOLITHOGRAPHY AND METHOD OF FABRICATING PHOTOMASK INCLUDING OPC BASED ON APPROXIMATED VALUE OF A CD OF A PATTERN

摘要

A method of fabricating a photomask includes OPC of a mask pattern based on an approximated (i.e., a predicted) critical dimension (CD) of a film pattern formed using the photomask. First, a photomask is provided, a photosensitive film pattern is formed by a lithographic process using the photomask, a CD of the photosensitive film pattern is determined using a scanning electron microscope (SEM), and a value of the CD of the photosensitive film pattern, at a point in time before the film pattern has been shrunk by the SEM, is approximated by measuring the CD using a reference microscope (e.g., an AFM) and the SEM or just by using the SEM in several sequences.