Critical dimension uniformity correction by scanner signature control

Abstract

A contribution to a wafer level critical dimension distribution from a scanner of a lithography system can be determined based on measured wafer level critical dimension uniformity distribution and a contribution to the wafer level critical dimension distribution from a photo mask. Light transmission (104) across the photo mask (162) can be measured, a transmittance variation distribution of the photo mask can be determined, and the contribution to the wafer level critical dimension distribution from the photo mask (162) can be determined (132) based on the transmittance variation distribution of the photo mask.

Dependencies are inferred from the claim text.