Patent ID: 7927773

Claim:
A device manufacturing method comprising the steps of: generating data on an original pattern; fabricating an original based on the generated data on the original pattern; exposing a substrate with an exposure apparatus using the original; and developing the substrate, wherein the generating step generates the data on the original pattern used in the exposure apparatus which projects the original pattern onto a substrate via a projection optical system to form an image of a target pattern on the substrate, and comprises: a determination step of determining a final assist pattern based on a light intensity distribution formed by the projection optical system when, of a main pattern and an assist pattern to accompany the main pattern which form the original pattern, only the assist pattern is inserted in an object plane of the projection optical system; and a combining step of combining the final assist pattern and the main pattern to generate data on the original pattern, wherein in the determination step, the final assist pattern is determined by repeating a process of calculating and evaluating the light intensity distribution while changing the assist pattern to be inserted in the object plane of the projection optical system, and a process of changing the assist pattern to be inserted in the object plane of the projection optical system.