Your shiny new smartphone and laptop can multitask between video calls, superfast searches, and detailed data crunching because of small, powerful microchips - the digital brains behind every computer's brawn. Some analysts say that the modern chip may soon run up against the limits of Moore's Law, the concept that the number of transistors in a circuit doubles about every two years. But thanks to a technique called extreme ultraviolet (EUV) lithography, it could be decades before microchips run out of room for improvement.
What is Extreme Ultraviolet Lithography?
EUV lithography was commercialized in 2019, but it took decades of research to get there. Much of that research was made possible by the unique capabilities of the Center for X-Ray Optics, a research facility located at DOE's Lawrence Berkeley National Laboratory (Berkeley Lab). CXRO scientists and engineers have worked side by side with microelectronics industry leaders to tackle the significant technological advances required to develop EUV lithography.
EUV lithography works like a very sophisticated photocopier. It can print circuit patterns that are 50 thousand times thinner than a human hair. These patterns are then transferred to silicon wafers to manufacture microchips. This technology enables chip manufacturers to print billions of transistors onto a chip the size of a fingernail. Chips with more transistors allow a computer to quickly and securely retain and process data. The best microchip today contains more than 100 billion transistors. Microchip manufacturers want to equip even smaller chips with even more transistors.
"Without EUV lithography, Moore's Law would likely have come to an end in 2019," said Patrick Naulleau, CEO of EUV Tech Inc. and former director of Berkeley Lab's Center for X-Ray Optics. "When you're talking about the future of microchip manufacturing, we're talking about extending Moore's Law - and that has been our primary focus for decades."
Building the Foundation for a Technology
Beginning in the late 1990s, Berkeley Lab researchers at the CXRO pioneered techniques to replace visible light with higher energy extreme ultraviolet light for lithography. This advance enabled chip manufacturers to print smaller features. That improvement in turn allowed more transistors to be squeezed into next-generation microchips with unprecedented speed and energy efficiency.
In 2001, EUV lithography was gaining more traction across the industry as a whole. At that time, Berkeley Lab established a partnership with SEMATECH, a broad-based semiconductor industry consortium, to continue advancing EUV lithography research.
For more than 20 years, CXRO's EUV lithography instruments have harnessed light from Berkeley Lab's Advanced Light Source, a DOE Office of Science User Facility. The Advanced Light Source is a synchrotron user facility that produces very bright extreme ultraviolet and soft X-ray light. It guides this light down highly specialized instruments called "beamlines" to experiment stations.
The Next Generation of Computer Chips
The commercialization of EUV lithography has enabled a whole new generation of ultrapowerful, compact, and energy-efficient computer chips. These advanced chips power everything from today's smartphones to artificial intelligence and self-driving cars.
"Advanced computer chips are critical to every part of our lives and staying at the forefront of this technology is essential to our economic security as well as national defense. To maintain our edge and our access to the world's most advanced chips, we must continue to be leaders in the technologies needed to manufacture these chips," said Naulleau.
Berkeley Lab scientists are now working with research partners from industry, National Labs, and academia to develop new EUV lithography materials that will enable the fabrication of smaller, faster, higher-density chips at the scale of just a few atoms.
"CXRO at Berkeley Lab has played a pivotal role in developing core expertise in EUV lithography and enabling new photoresist materials. Having industry-accessible pathfinding capabilities at the CXRO is an excellent example of how well government and industry can work together in advancing EUV lithography and extending Moore's Law," said Eric Panning, Lavorro's Vice President of Product Engineering and former Intel founder of the CXRO EUREKA program for advanced EUV patterning.
After setting the foundation for this revolutionary technology, the lab is looking forward to what it can do next.
"The Center for X-Ray Optics has played a key and pioneering role in enabling EUV lithography, so that it could be used by leading-edge chipmakers in their most advanced manufacturing processes," said CXRO Director Bruno La Fontaine. "CXRO will continue to play a vital role in helping push the boundaries of Moore's Law even further in the many years to come."