METROLOGY METHOD AND ASSOCIATED METROLOGY AND LITHOGRAPHIC APPARATUSES

摘要

Disclosed is a metrology method relating to measurement of a structure on a substrate, said structure being subject to one or more asymmetric deviation. The method comprises obtaining at least one intensity asymmetry value relating to the asymmetric deviation, wherein the at least one intensity asymmetry value comprises a metric related to a difference or imbalance between the respective intensities or amplitudes of at least two diffraction orders of radiation diffracted by said structure; determining at least one phase offset value corresponding to the one or more asymmetric deviation based on said at least one intensity asymmetry value; and determining one or more measurement correction for said one or more asymmetric deviation from the one or more phase offset.