ASML

You will never see an ASML machine in a data center. It sits in a semiconductor fab — a $20 billion factory, usually in Taiwan, South Korea, or the United States, where chips are manufactured.

Inside the fab, in a cleanroom where the air contains fewer than 10 particles per cubic meter (operating rooms have 10,000+), ASML's EUV lithography machine occupies a space the size of a double-decker bus. It weighs 180 tonnes. It was shipped in 40 freight containers and took months to assemble on-site.

Here is what it does: it generates extreme ultraviolet light — light with a wavelength of 13.5 nanometres, which is shorter than any light you can see — by firing a high-powered laser at tiny droplets of molten tin, 50,000 times per second. Each droplet explodes into a plasma that emits EUV light. That light is focused through a series of the flattest mirrors ever manufactured (polished to atomic-level smoothness, made by Zeiss in Germany) onto a silicon wafer coated with light-sensitive chemicals. The pattern of light creates the circuit design — transistors, wires, connections — at a scale where features are measured in a few dozen atoms wide.

One EUV machine can process 150-200 wafers per hour. Each wafer becomes hundreds of chips. A single TSMC fab may contain 20-30 of these machines, each running 24 hours a day.

The AI infrastructure buildout requires a step-function increase in advanced chip production, and every one of those chips goes through ASML lithography. TSMC is spending $38-42 billion annually to expand capacity, much of it on 2nm and below nodes that require more EUV patterning steps per wafer than previous generations. The 2nm node uses gate-all-around (GAA) transistor architecture — the first fundamental transistor design change since FinFET in 2011 — demanding tighter lithographic precision. More EUV steps per wafer means more machine-hours per chip, which means TSMC needs more ASML machines even if total wafer starts stay flat. ASML's backlog stands at EUR 38B+ with 12-18 month delivery lead times, a direct forward indicator of how many advanced chips the world will manufacture in 2027-2028.