February 21, 2006 – IBM Corp., along with Tokyo-based JSR Corp. and its US subsidiary JSR Micro Inc., say they have demonstrated sub-30nm patterning using deep-ultraviolet (DUV) 193nm optical lithography, indicating that immersion lithography can be extended to and beyond the 32nm node without the need for new and expensive techniques, such as extreme-ultraviolet (EUV).

The firms demonstrated 29.9nm 1:1 patterns using a high-refractive index liquid as the immersion fluid and ArF photoresist, in experiments run on IBM’s NEMO interference immersion lithography test apparatus, which uses two intersecting laser beams to create light-and-dark interference patterns with spacings closer than can be made with current chip-making apparatus. The lens and fluid had indices of about 1.6, with photoresist index of refraction of 1.7. Further research will aim to extend the lens, fluid and photoresist materials indices of refraction to 1.9.

“This result is the strongest evidence to date that the industry may have at least seven years of breathing room before any radical changes in chip-making techniques would be needed,” stated Robert Allen, manager of lithography materials at IBM’s Almaden Research Center.

“We believe that the introduction of high refractive index liquid imaging will enable the extension of ArF lithography over two technology nodes,” added Mark Slezak, technical manager of JSR Micro Inc. “Our industry faces tough questions about which lithography technology will allow us to be successful below 32 nanometers. This new result gives us another data point favoring the continuation of optical immersion lithography.”