EUV uses 13.5nm light to print the smallest features on modern chips. The way that light is made and steered is one of the strangest feats in manufacturing.
A visual story — shown as much as told.
Every advanced chip is, at its core, a pattern printed onto silicon. Lithography is the printing step, and extreme ultraviolet lithography, EUV, is the technology that lets the most advanced fabs print features small enough for today's leading nodes. The basic idea is simple. The execution is closer to controlled science fiction.
Printing with light#
Chip manufacturing builds circuits layer by layer. For each layer, the wafer is coated with a light-sensitive chemical called photoresist. Light is then projected through a patterned mask, the photomask, onto the resist. Where the light lands, the resist changes chemically, so it can be washed away (or kept) in the next step. That reveals a pattern that gets etched into the material underneath. Repeat this dozens of times, with different masks and materials, and you build up transistors and the wiring that connects them.
The limit on how small a feature you can print is tied to the wavelength of the light. Shorter wavelengths can resolve finer detail. For years the industry printed with deep ultraviolet light at a 193nm wavelength and used clever tricks to push it well past its natural limit. Those tricks eventually ran out of room.
Discussion