Carl Zeiss, Sematech Design Metrology Tool

Sematech and Carl Zeiss SMT of Jena, Germany, announced they have completed a design for a photomask registration and overlay metrology system they say will enable production of more advanced photomasks with better image placement accuracy -- in particular, in double-patterning lithography, which requires tighter image placement control for photomasks. The system determines the accuracy of mask-pattern alignment and registration for 32-nm half-pitch and beyond photomasks. Double patterning is a technology for enhancing feature density using 193-nm wavelength technology. The metrology system also forms part of the infrastructure of extreme ultraviolet lithography, Sematech said. “Future lithographic scaling places a high reliance on very tight overlay control of the various device levels, and the photomask is a key component of the overlay error budget,” said Michael Lercel, Sematech director of lithography and chairman of the ITRS (International Technology Roadmap for Semiconductors) Litho Working Group. “This new system will get us past several previously ‘no known solution’ challenges.” The tool is targeted for production in 2009, with mask manufacturers as the primary customers. Sematech, based in Albany, N.Y., is a consortium of chipmakers.