A method for modeling metrology data over a substrate area and associated apparatuses

A method for modeling metrology data over a substrate area relating to at least one substrate in a lithographic process, the method comprising:

• obtaining first exposure model data, the first exposure model data relating to a first model fitted to first exposure metrology data for performing a first exposure on the at least one substrate;
• obtaining second exposure metrology data relating to a second exposure on the at least one substrate, the second exposure being exposed subsequent to exposure of the first exposure;
• subtracting metrology content from the second exposure metrology data, the metrology content being obtained from the first exposure model data or a component thereof and/or the first exposure metrology data, to obtain corrected second exposure metrology data;
• fitting, by a hardware computer system, a second model to the corrected second exposure metrology data or a component thereof, the second model being different to the first model;
• and
• determining, by the hardware computer system, an output model from at least the second model, the output model being corrected for a model mismatch resultant from the first model and the second model.