Patent ID: 7569312

Claim:
A mask data creation method for creating mask data for a photomask including a mask pattern formed on a transparent substrate and a transparent portion of said transparent substrate where said mask pattern is not formed, comprising the steps of: (a) generating a main pattern corresponding to a desired unexposed region of a resist formed by irradiating said resist with exposing light through said photomask; (b) determining a shape of a phase shifter that is disposed within said main pattern and transmits said exposing light in an opposite phase with respect to said transparent portion; (c) disposing an auxiliary pattern for diffracting said exposing light in a position on said transparent substrate away from said phase shifter by a given distance; (d) setting an edge of said main pattern corresponding to a boundary between said main pattern and said transparent portion as a CD adjustment edge; (e) predicting, through simulation, a dimension of a resist pattern formed by using said main pattern including said phase shifter and said auxiliary pattern; and (f) changing a shape of said main pattern by moving said CD adjustment edge when said predicted dimension of said resist pattern does not accord with a desired dimension.