Patent ID: 6811934
Filing Date: 2004-11-02
Classification: G03F

Abstract:
A method of producing a physical mask, comprising:generating a database representation of the mask; correcting the database representation, thereby producing a corrected database representation, wherein correcting the database representation comprises: determining overlay error variation across a field of the mask; defining at least two zones within the field of the mask, wherein each zone is a continuous portion of the field containing substantially similar overlay error values, and wherein each zone has a nominal overlay error value; defining a correction for each of the at least two zones, wherein the correction for each zone is approximately the nominal overlay error value for that zone; mapping each of a plurality of features to one of the at least two zones; and modifying coordinates of each of the plurality of features in response to the correction for the zone in which each feature is mapped; and selectively establishing opaque areas on a clear support in response to the corrected database representation.