The more common maskless route is laser direct write. That is capable to micron level dimensions, and multicolor variants have been proposed to allow submicron.

The more common maskless route is laser direct write. That is capable to micron level dimensions, and multicolor variants have been proposed to allow submicron. Ebeam direct write is capable to NM level features. Just slow. http://www.periodicstructures.com/ http://www.periodicstructures.com/ Has some neat papers on this.