Abstract: A method, computer program and associated apparatuses for metrology. The method includes determining a reconstruction recipe describing at least nominal values for use in a reconstruction of a parameterization describing a target. The method includes obtaining first measurement data relating to measurements of a plurality of targets on at least one substrate, the measurement data relating to one or more acquisition settings and performing an optimization by minimizing a cost function which minimizes differences between the first measurement data and simulated measurement data based on a reconstructed parameterization for each of the plurality of targets. A constraint on the cost function is imposed based on a hierarchical prior. Also disclosed is a hybrid model method comprising obtaining a coarse model operable to provide simulated coarse data; and training a data driven model to correct the simulated coarse data so as to determine simulated data for use in reconstruction.

Abstract: A method, computer program and associated apparatuses for metrology. The method includes determining a reconstruction recipe describing at least nominal values for use in a reconstruction of a parameterization describing a target. The method includes obtaining first measurement data relating to measurements of a plurality of targets on at least one substrate, the measurement data relating to one or more acquisition settings and performing an optimization by minimizing a cost function which minimizes differences between the first measurement data and simulated measurement data based on a reconstructed parameterization for each of the plurality of targets. A constraint on the cost function is imposed based on a hierarchical prior. Also disclosed is a hybrid model method comprising obtaining a coarse model operable to provide simulated coarse data; and training a data driven model to correct the simulated coarse data so as to determine simulated data for use in reconstruction.

Abstract: Methods and apparatuses for determining a property of a structure fabricated on a substrate, by: determining a measured characteristic from pixels of a measured pupil image of the structure, the measured characteristic having less information than the measured pupil image; generating an initial simulated characteristic corresponding to the measured characteristic and based on a candidate model of the structure; comparing the measured characteristic to the simulated characteristic in an iterative method until a difference therebetween is less than a coarse threshold; generating an initial simulated pupil image based on the coarse model as the candidate model; comparing at least a portion of the measured pupil image to at least a portion of the simulated pupil image in an iterative method until a difference therebetween is less than a fine threshold.