A cutting-edge device for manufacturing computer chips utilizes enormous, nearly flawless mirrors to produce minuscule transistors and circuit patterns.
A record-breaking light source, larger than a London double-decker bus, can now etch structures on a silicon wafer that are just 8 nanometres (nm) wide. These are believed to be the smallest patterns ever created in a single step using a commercial chip-patterning system. According to the manufacturer, this system could enable chips to carry nearly three times more transistors than those made with previous-generation lithography equipment.
The machine works by projecting extreme ultraviolet (EUV) light onto a “mask,” which reflects the patterned light onto silicon wafers coated with light-sensitive chemicals. These chemicals harden in the pattern projected, and the wafer is then etched chemically. This cycle is repeated multiple times to create all the electronic elements of the chip, including the tiny transistors and the ultra-fine wiring connecting them.
This approach, called EUV lithography, is not entirely new. However, the latest model features exceptionally powerful optics, allowing the creation of even smaller transistors. Packing more and smaller transistors into a chip of a fixed size drives advances in computing. Chips with higher transistor counts can also boost the computational power of AI data centers without significantly increasing energy use.
The record-setting EUV system was presented at the SPIE Advanced Lithography + Patterning conference in San Jose, California, in February. The demonstration was given by a representative of ASML, a company based in Veldhoven, the Netherlands.
ASML has already delivered around ten of these devices, each costing approximately US$400 million, to major chip manufacturers such as Intel and SK hynix. These companies plan to use the machines to build the next generation of chips. Maarten Voncken, ASML’s head of research metrology, notes that the AI surge has created “monumental” demand, both in terms of chip quantity and the level of miniaturization required.
Extending Moore’s Law
Modern high-performance chips—used in smartphones and AI data center servers—feature structures built with near-atomic precision. Moore’s Law, a guiding principle in the chip industry, predicts that the number of transistors on a chip roughly doubles every two years. While not a physical law, it has held true due to decades of intense engineering and physics breakthroughs. However, maintaining Moore’s Law is becoming increasingly difficult as AI applications drive the need for faster and more powerful chips.
Enhancements in lithography technology help meet this challenge. The smaller the light wavelength, the finer the features that can be etched on a wafer. Other properties of the lithography system, such as its numerical aperture, are also critical. Systems with higher numerical aperture can project light at a wider range of angles, improving image contrast and resolution. This allows chipmakers to achieve higher transistor densities on their chips.
From Early Labs to AI Data Centers
In the 1990s and 2000s, lithography tools used deep ultraviolet light with a 193 nm wavelength—the shortest light usable with conventional lens designs similar to those in eyeglasses and binoculars. The new EUV systems, by contrast, operate at much shorter wavelengths and employ advanced optics to push the boundaries of transistor miniaturization, meeting the escalating demands of today’s AI-driven world.
