On-product overlay enhancement using advanced litho-cluster control based on integrated metrology, ultra-small DBO targets and novel corrections

Aggressive on-product overlay requirements in advanced nodes are setting a superior challenge for the semiconductor industry. This forces the industry to look beyond the traditional way-of-working and invest in several new technologies. Integrated metrology(2), in-chip overlay control, advanced sampling and process correction-mechanism (using the highest order of correction possible with scanner interface today), are a few of such technologies considered in this publication.