ASML Holding N.V.
Correction using stack difference

Abstract:

A method including obtaining a fit of data for overlay of a metrology target for a patterning process as a function of a stack difference parameter of the metrology target; and using, by a hardware computer, a slope of the fit (i) to differentiate a metrology target measurement recipe from another metrology target measurement recipe, or (ii) calculate a corrected value of overlay, or (iii) to indicate that an overlay measurement value obtained using the metrology target should be used, or not be used, to configure or modify an aspect of the patterning process, or (iv) any combination selected from (i)-(iii).