Method for forming a critical dimension test structure and its use

摘要

A method for forming a critical dimension test mark, and the use of the mark to characterize and monitor imaging performance is provided. Methods in accordance with the present invention encompass an exposure of an essentially standard critical dimension bar at each of two overlapping orientations that are rotated about an axis with respect to each other. The overlapped portion forming a critical dimension test mark that is useful for enabling low cost, rapid determination of sub-micron critical dimensions for characterizing exposure tool imaging performance and in-process performance monitoring using optical measurement systems.