Abstract: A method for characterizing a patterning process, the method including obtaining a plurality of values of stitching errors made along one or more boundaries between at least two patterned adjacent fields or sub-fields on a substrate; and fitting, using a hardware computer system, a distortion model to the plurality of values to obtain a fingerprint representing deformation of a field or sub-field out of the at least two patterned adjacent fields or sub-fields.

Abstract: An arrangement for and a method of automatically selecting substrate alignment marks on a substrate in a lithographic apparatus or overlay metrology targets in an overlay metrology apparatus. The apparatus has a processor and a memory connected to the processor. The memory stores locations of one or more sets of substrate alignment marks or overlay metrology targets available for selection and selection rules to select suitable substrate alignment marks or overlay metrology targets from this at least one set. The selection rules are based on experimental or theoretical knowledge about which substrate alignment mark or overlay metrology targets locations are optimal in dependence on one or more selection criteria.