摘要 |
Method to calibrate a substrate table position in a lithographic apparatus includes providing a substrate on the substrate table with a two dimensional arrangement of patterns; positioning the substrate table with a positioning system; measuring positions of the substrate table in at least two dimensions with a position measurement system; reading out the arrangement of patterns as a function of the measured positions of the substrate table with a pattern read out system to obtain pattern read out results; deriving position errors as a function of the measured positions of the substrate table compared with the pattern read out results; calibrating the positioning system using the position errors, the calibrating including determining drift influences of the positioning system, correcting the position errors as a function of the corresponding two dimensional position of the substrate table with the determined drift influences, and calibrating the positioning system with the corrected position errors.
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