Open any wikipedia article about “x nm process” and one of the first paragraphs will be something like this:
The term “2 nanometer”, or alternatively “20 angstrom” (a term used by Intel), has no relation to any actual physical feature (such as gate length, metal pitch or gate pitch) of the transistors. According to the projections contained in the 2021 update of the International Roadmap for Devices and Systems published by the Institute of Electrical and Electronics Engineers (IEEE), a “2.1 nm node range label” is expected to have a contacted gate pitch of 45 nanometers and a tightest metal pitch of 20 nanometers.[1]
It used to be that the “60nm process” was called that because the transistor gate was 60nm.
Eli12?
Open any wikipedia article about “x nm process” and one of the first paragraphs will be something like this:
It used to be that the “60nm process” was called that because the transistor gate was 60nm.
The best thing you can do to understand this is watch the latest Veritasium video about ASML.
ASML figured out how to make ultraviolet light very close to X-Ray wavelength using some incredible physics and engineering.
https://www.youtube.com/watch?v=MiUHjLxm3V0