San Jose, Calif. -- The lithography world has suddenly turned upside-down as the industry gets socked by a double whammy: The window of opportunity is slowly closing on extreme-ultraviolet (EUV) lithography for IC production, but the most likely alternative--a version of 193-nanometer immersion--is proving expensive. The added costs could have some serious implications for chip scaling.
At last week's SPIE Advanced Lithography conference here, there were troubling signs that oft-delayed EUV technology could get pushed out even further, to the 16-nm node, in 2013--if it materializes at all. That could set back leading-edge chip makers such as Intel and Samsung, which were hoping to get their hands on working EUV tools for the early-development phases of the 22-nm node in 2011.
EUV's problems open the door for a crop of emerging technologies, such as immersion, maskless and nanoimprint lithography. But at least for the 32- and 22-nm nodes, the leading contender is 193-nm immersion, equipped with the new buzzwords "double exposure" and "double patterning."
Although various entities have proven the viability of double exposure and double patterning, the technology is more expensive than today's patterning schemes. That means chip-manufacturing costs could take a big hit over time. There are other ominous implications for the continued push to reduce IC bit prices at each process technology node.
"With double exposure, bit costs will continue to decelerate, but not at the rate we've experienced in terms of historical trends," said Harry Levinson, manager of strategic lithography technology for the Technology Research Group at Advanced Micro Devices Inc.
At SPIE, Applied Materials, Hynix, IBM and IMEC separately presented methodologies that promise to reduce the costs of the technology.
Regarding the delay of EUV for the early stages of the 22-nm node, AMD's Levinson summarized the situation: "I'm a little disappointed. Time is running out [for the technology]."
Indeed, "If we don't find [new lithography] solutions, Moore's Law breaks down," said analyst G. Dan Hutcheson, chief executive at VLSI Research Inc.
Hutcheson still believes there's a place for EUV. "I would say that EUV has a future. It's going to be sometime after 22 nm. EUV will pop up at 16 nm," he said. Hutcheson was more pessimistic about maskless and nanoimprint lithography. "Maskless is not [likely] to make it other than for research," he said. "Nanoimprint has applications other than semiconductors."
That leaves 193-nm immersion as the near-term choice. "A year ago, people were saying double patterning is not going to happen. Now everyone is talking about double patterning," said Hutcheson.
The pessimism surrounding EUV deepened recently when IBM Corp. delivered a bombshell by saying that EUV was not expected to be ready for the early development phases at the 22-nm node (36.5-nm half-pitch) for logic, as the company previously hoped. Instead, IBM and its development partners--including AMD, Chartered, Freescale, Infineon, Samsung and others--claim they will extend 193-nm immersion lithography down to the 22-nm node, thanks in part to double-patterning or double-exposure techniques.
"EUV will be late for early development at the 22-nm node," George Gomba, IBM distinguished engineer and director of lithography technology development, said during a presentation at SPIE. "Water immersion will be the only solution that meets the two-year cycle and requirements at 22 nm.''
EUV's main champion, Intel Corp., agreed with IBM's assessment. "We would say the same thing," said Intel senior fellow Yan Borodovsky, director of advanced lithography in the company's Technology and Manufacturing Group. EUV still suffers from the "same issues" that have dogged development all along, he said, including the well-documented lack of photomasks, power sources and resists--and a staggering price tag of possibly $70 million per lithography machine.
"The devil is in the mask, the source and the cost," Burn Lin, senior director of the micropatterning division at silicon foundry giant Taiwan Semiconductor Manufacturing Co. Ltd., said at SPIE.
EUV is dead in the water, said Gerhard Gross, CEO of maskless-lithography developer IMS Nanofabrication AG. "It's not coming," he said. "I don't think anybody is committed to developing the mask infrastructure."
Intel's Borodovsky said the next 12 to 18 months will be critical for the realization of EUV, but he insisted the technology is still on Intel's road map for use at the 22-nm node in 2011.