To: FJB who wrote (1217 ) 9/20/2006 10:18:35 AM From: niek Read Replies (1) | Respond to of 42879 Immersion lithography is the strongest candidate for 32-nm node, says analyst The Semiconductor Reporter September 20, 2006 NEW TRIPOLI, Pennsylvania -- Nikon Corp. will ship between 10 and 15 immersion lithography tools this year, according to Robert Castellano, president of market research firm The Information Network. Nikon "could end up leading the market this year despite ASML's early lead," he said today. "Nikon will be the first company to ship by the end of this year a hyper-NA [numerical aperture] immersion system, the S610C, with a 1.30 NA lens designed for 45-nm volume production," Castellano said. The analyst said he believes that 193-nm immersion lithography will likely be extended for use at the 32-nm node. Whether that is by going to new high-index-of-refraction fluid and lens materials, or by double-exposure patterning, or a combination of techniques, is not yet clear. Progress at numerous companies and universities is being made to identify and develop high-index immersion liquids with indices of refraction in the range of 1.63 to 1.65 (water's is 1.3). Likewise, lutetium aluminum garnet has been thoroughly evaluated and is a leading candidate for a high-index bottom lens material, Castellano said. As an alternative to moving to high-index materials, double exposure is being evaluated, he noted. But double patterning will require two full lithography and etch steps. What's needed, Castellano believes, is an enhanced resist. The loss of image contrast can be avoided if the resist response is non-linear. If such a material could be found, 32-nm IC development could begin immediately on current lithography tools, Castellano asserted. In the extreme ultraviolet lithography arena, tool development is ahead of infrastructure development, Castellano pointed out. ASML has already shipped alpha demo tools, but limitations related to masks, light sources, resists, and contamination control remain.