Patent ID: 7548315

Claim:
A lithography system, comprising: an illumination system configured to generate an illumination beam of radiation, comprising, a source of radiation configured to produce a beam of radiation; and an optical system configured to transmit a first portion of the illumination beam having a first polarization direction during a first portion of a cycle and a second portion of the illumination beam having a second polarization direction during a second portion of the cycle; a patterning device including first and second patterns having respective first and second optical proximity correction corresponding to the first and second polarization directions, the first and second patterns configured to pattern respective ones of the first and second portions of the illumination beam of radiation; a detector configured to detect characteristics of the beam of radiation and to generate control signals that control whether the first or second pattern of the patterning device is used based on the detected characteristics; and a projection system configured to project the first and second patterned beams onto a target portion of a substrate.