Patent ID: 7185312
Filing Date: 2007-02-27
Classification: G03F

Abstract:
1. An exposure method for correcting pattern line width variation occurring during a development process in fabricating a photomask, the method comprising: forming a measuring pattern on a photomask substrate according to a test pattern having a predetermined line width; dividing the photomask substrate on which the measuring pattern is formed into meshes, measuring a line width of the measuring pattern in each mesh, and determining a pattern line width variation ΔCD, which is a difference between the measured line width and the set line width of the test pattern; making a graph of a distribution of pattern line width variation ΔCD(r) measured for each mesh, separated from a reference mesh by a distance r; from the graph, estimating a pattern line width variation ΔCD(x) at an arbitrary point, separated from the reference mesh by a distance x on the photomask substrate; correcting pattern line width data with respect to each point on the photomask substrate such that a pattern line width increases in an area where the estimated pattern line width variation ΔCD(x) is negative, and a pattern line width decreases in an area where the estimated pattern line width variation ΔCD(x) is positive; and applying to an exposure apparatus the pattern line width data corrected with respect to each point on the photomask substrate.