ASML Holding N.V.
Methods of controlling a patterning process, device manufacturing method, control system for a lithographic apparatus and lithographic apparatus

Abstract:

Performance measurement targets are used to measure performance of a lithographic process after processing a number of substrates. In a set-up phase, the method selects an alignment mark type and alignment recipe from among a plurality of candidate mark types by reference to expected parameters of the patterning process. After exposing a number of test substrates using the patterning process, a preferred metrology target type and metrology recipe are selected by comparing measured performance (e.g. overlay) of performance of the patterning process measured by a reference technique. Based on the measurements of position measurement marks and performance measurement targets after actual performance of the patterning process, the alignment mark type and/or recipe may be revised, thereby co-optimizing the alignment marks and metrology targets. Alternative run-to-run feedback strategies may also be compared during subsequent operation of the process.