Dr. Lars Liebman at IBM gave a very clear talk about the need for double patterning at the 22nm and 14nm nodes while at DAC a couple of months ago. Until EUV is ready for production, which is not expected until 2014, we will continue to rely on optical lithography and will need double patterning. To see just how scary (or not) this might be, here’s the video of Liebman’s talk:
Dr. Liebman has been writing about lithographic topics for many years. Here’s a link to one of his earlier papers I found to be very readable (as a non-IC lithographer): Layout Impact of Resolution Enhancement Techniques: Impediment or Opportunity?
And here’s a link to Richard Goering’s writeup of this video: Video: Easing the Design Challenges of Double Patterning at 20nm