| 摘要 |
PROBLEM TO BE SOLVED: To obtain fixed correction accuracy regardless of a plotting area factor, by more finely dividing the gradation as the plotting area factor becomes higher and, at the same time, to improve a correction accuracy by dividing a range between a maximum value or a value close to the maximum value and a minimum value or a value close to the minimum value of a correcting quantity into a plurality of gradations. SOLUTION: The relation between an optimum irradiating quantity Dk found from a representative correcting quantity Mk described by a gradation number (k) and a reference irradiating quantity Do is expressed by Dk =Mk×Do, and the line width variation dw per unit irradiating quantity dD is expressed by the linear expression dw/dD=A×ρ+B of a plotting area factorρ(where, A and B represent coefficients which depends upon the substrate and resist). In this case, a division and representative irradiating quantity are set so thatΔW is constant irrespective of the area factorρwhen the pattern differenceΔW which occurs at the boundary between gradation numbers (k) and (k+1) is expressed byΔW=(Mk -MK+1 )×(A×ρ+B)×Do. Therefore, level difference of a line width which occurs at the boundary between each of 256 divided gradations becomes uniform and errors of all plotting area factors can be made uniform.
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