Universities win $17 million EUV grant

FORT COLLINS, CO—Three leading U.S. research universities have received a $17 million National Science Foundation (NSF) grant to develop laser-driven light sources for extreme-ultraviolet (EUV) lithography. The technology is being developed through research conducted at the new NSF Engineering Research Center (ERC) for Extreme Ultraviolet (EUV) Science and Technology, headquartered at Colorado State and a joint collaboration among Colorado State University (Fort Collins, CO), the University of Colorado at Boulder, and the University of California at Berkeley. The goal of the center is to develop solutions to a variety of challenging scientific and industrial problems related to EUV lithography.

Hollow-fiber EUV photonics generate laserlike beams (a).^{1, 2, 3} A high-power femtosecond generates EUV light (b). Laser-like EUV beams exhibit high-quality interference patterns (c).⁴ An EUV source developed at Colorado State University is end-pumped by a laser (d).Click here to enlarge image

Compact laser technologies recently developed at the University of Colorado at Boulder and Colorado State have made small EUV laser sources that fit on a single table practical for the first time (see figure). These new tools make it possible to implement advanced EUV science in a small laboratory, in some cases with powers and accuracy previously available only at one of the few building-size EUV facilities around the nation.

"Most EUV science and technology development is presently being conducted at a handful of large national light source facilities, but to realize the full potential of EUV, there is an urgent need to make this technology accessible to university, national and industrial laboratories," said Margaret Murnane, a professor at the University of Colorado at Boulder and deputy director of the ERC. "Throughout the lifespan of the ERC, we expect to make compact coherent EUV sources at significantly shorter wavelengths than is now possible, and to reduce their scale to desktop, and in some cases, even laptop size."

Nationally and worldwide, there is a massive research push to develop nanotechnology, allowing the creation of electronic circuits and devices fabricated from single atoms and molecules. EUV light will be a key component for the creation of nanoscale technologies. "Extreme-ultraviolet wavelengths correspond to the scale relevant to nanotechnology," said David Attwood, director of UC Berkeley's Center for X-Ray Optics and associate director of the ERC. "For the nation to make rapid progress in this competitive field, a wide variety of techniques are needed to make it possible to see small objects, to manipulate, and to manufacture them."

Enabling technology

Extreme-ultraviolet technology is positioned to become the critical enabling technology of the near future, and the NSF ERC in EUV is positioned as a leader to drive this technology. Extreme-ultraviolet technology is expected to be the prime candidate for creating advanced integrated circuits, with high-volume production beginning in 2007. By 2009, six major technology companies, including IBM, Motorola, and Intel, plan to produce computer technologies using EUV radiation with chips based on 16-nm features that will have speeds of 20 GHz, about ten times faster than current technologies.

"We will develop two types of EUV laser sources and applications as part of the center—one based on capillary-discharge plasmas as a laser medium to create an actual EUV laser, and the other based on frequency upconversion of a femtosecond laser in a gas, that upconverts a laser beam in the near-infrared region of the spectrum into the EUV," said Murnane. "Both sources are tabletop sources that have been shown to generate spatially coherent EUV beams with different characteristics that are suitable for a wide variety of applications."

One long-term goal of the ERC is to create biological soft-x-ray microscopes that can image minute details of individual living cells. Other opportunities are expected to emerge from the possibility of focusing EUV radiation to unprecedented small spot sizes, short pulse durations, and extremely high intensities. These advances should open up new areas of investigation including surface studies, chemical and materials dynamics studies, EUV nonlinear optics, and biological studies.