LOS ANGELES Intel Corp. said it will invest in the tools needed to create EUV masks on a regular basis, starting out with masks for 90-nm test SRAM chips later this year. Intel's immediate goal is make EUV masks that could be compared with similar-complexity 90-nm masks created for 193-nm lithography.
Barry Lieberman, engineering manager of Intel's mask shop in Santa Clara, Calif., said Intel is "a couple of months off from having a pilot line that has a dedicated toolset for EUV masks." He made the announcement here during the Litho Forum, sponsored by International Sematech, on Wednesday (Jan. 28th).
By 2005, the mask shop will be turning out 65-nm EUV masks. The 45-nm masks will have to wait two years, until 2007, because the mask writing machines for the 45-nm node are not expected to be ready until then.
Intel's goal is to use EUV (extreme ultraviolet) lithography for the 32-nm node, beginning in 2009.
Intel has ordered six EUV mask tools, four of which are related to metrology and inspection. Most of the tools will not come from established mask capital equipment suppliers, he added, rather from innovative metrology companies that Intel has identified.
Intel plans to install an M1350 confocal microscopy mask blank defect inspection tool from Lasertec Corp. (Tokyo) capable of detecting 30-nm defects on the blanks.
Intel also will install an interferometry tool to measure the flatness of the mask, and an actinic (at the 13.5-nm EUV wavelength) reflectometry tool to measure the reflectance of the multilayers. It will buy a deposition tool from Sputtered Films, a Tegal company, for putting down the absorber layer.
Because focused ion beam equipment will not be extendable, Intel has installed a repair tool that is based on electron beam technology, he said.
The last tool in the suite of six is expected to be a custom-built microscope that uses the 13.5-nm wavelength EUV light to inspect the reticles. That microscope is being built by Exitech Ltd. (Oxford, England), the same company that is finishing up an EUV microscanner expected to be delivered to the Sematech Albany mask blank evaluation center in Albany, N.Y., now scheduled for delivery in May.
Intel expects to receive its Micro Exposure Tool (MET) from Exitech next month for use at Intel's Portland, Oregon process development center.
Peter Silverman, an Intel fellow, said Intel will invest "tens of millions" of dollars in the EUV mask equipment. Intel also will leverage the existing and future tools in the company's mask shop.
"Optical is always limited by metrology," Silverman said, adding that the better inspection tools will give Intel the means to "bootstrap our way up, lifting ourselves as we go along."
"We are going to use the same methods to improve our EUV mask-making ability that we use to bring up a new process technology, improving yields as we go along," he said.