Patent ID: 7643976

Claim:
A method of identifying lens aberration sensitive patterns in an integrated circuit chip, the method comprising: providing an exposure system; communicably coupling the exposure system to an operator data processing system configured to operate the exposure system, wherein the operator data processing system comprises a computer-readable medium, the medium having stored thereon a sequence of executable instructions; identifying lens aberration sensitive patterns in the chip by executing instructions for: performing a first simulation of a layout to simulate a contour without lens aberration; performing a second simulation of the layout to simulate a contour with lens aberration; determining a difference of critical dimension between the contour with lens aberration and the contour without lens aberration; and selecting at least one lens aberration sensitive pattern from a plurality of layouts based on the difference in critical dimension, wherein selecting at least one lens aberration sensitive pattern from a plurality of layouts based on the difference in critical dimension includes determining a critical dimension range for the layout through different positions of a slit based on the difference of critical dimension.