Extending Moore's Law with Double-Patterning

For decades Moore's law was largely driven by reducing the wavelength and increasing the numerical aperture used for lithography.  We've been stuck on 193nm lithography for more than a decade and the next wavelength -- 13.5nm EUV -- has some significant challenges to overcome before it is ready for production.  Until then we continue to extend Moore's Law by decomposing complicated photomask patterns into simpler factors.  Here's an interesting presentation by AMAT's Chris Bencher that talks about the different flavors of multiple patterning being used today.

http://www.semicontaiwan.org/en/sites/semicontaiwan.org/files/docs/applied_materials_cbencher_litho_forum_2013_for_web_download.pdf