Will EUV litho be ready for 22nm?

Lithography scaling is getting harder and becoming affordable to fewer companies, leaving transitions to new processing nodes, almost metronomic throughout the semiconductor industry's history, to slow, according to experts at the IMEC research institute.

And the belated arrival of extreme ultraviolet (EUV) lithography is a primary manifestation of that slowdown. Nonetheless: "EUV is the only technology available for mass production sub 20nm," according to Luc van den Hove, president and CEO of IMEC.

And so it all depends on whether you see the cup as half-full, or half-empty.

There's no doubt that the IMEC research institute and its semiconductor and equipment partners are making progress with EUV lithography. But that progress is against the ticking clock of Moore's Law and the International Technology Roadmap for Semiconductors (ITRS). And against that moving target EUV lithography is slipping backwards. EUV is creeping ever closer to the technical specifications that would allow high volume manufacturing but it now looks unlikely to arrive in time to take much part in the 22nm node, according to Kurt Ronse, director of lithography programs at IMEC.

And there has been a delay in the arrival of the long-awaited NXE3100 EUV lithography pre-production tool from ASML Holdings NV. First exposure on the tool is expected to be seen at Veldhoven any time now, according to Ronse, but he is not expecting to install IMEC's example of the tool until late this year. "We will not have the tool up and running this year," he said.

Only 18 months ago Ronse was predicting that EUV lithography would be the way the semiconductor industry would pattern critical layers at the 22nm node. He was also expecting the pre-production lithography tool to arrive early in 2010 or at least in the first half of the year.

At the start of a presentation to the press ahead of the IMEC Technology Forum for 2010, Ronse said: "We expect volume production EUV scanners in 2012. It is very unlikely that EUV will be ready for 22nm NAND flash." But Ronse does feel that EUV lithography could arrive in time for 22nm half-pitch DRAM and 16nm logic which equates roughly to 22nm half-pitch memory.

If production EUV scanners arrive at chip companies in 2012 that will be the starting point for internal commercial process development and it will likely be 2014 before EUV lithography is now seen in high volume manufacture, Ronse said.