KLA Corporation
PER-SITE RESIDUALS ANALYSIS FOR ACCURATE METROLOGY MEASUREMENTS

Abstract:

Systems, metrology modules and methods are provided, which identify, per wafer site, components of residuals from measurement of metrology metric(s), and optimize measurement parameters for each site, according to the identified residuals' components. Certain embodiments utilize metric landscapes to identify sensitive sites and/or to identify sites exhibiting highest accuracy, and corresponding metrics may be combined over the wafer to further enhance the metrology performance. Zonal analysis may be used to reduce the systematic errors, and disclosed per-site analysis may be used to further reduce the non-systematic error components, and relate the remaining residuals components to process variation over the wafer.