Hackaday: Laser Doping His Way To Homemade Silicon Chips.
https://hackaday.com/2021/12/28/laser-doping-his-way-to-homemade-silicon-chips/


Jim Bell's comment:

I can see the attraction, but it would probably be more useful if individuals designed and laid out the circuitry, and the layouts are transferred to a commercial semiconductor fab for manufacture.  

There, the layouts for many different designer's circuitry will be combined on a single large wafer.  These designs will presumably have identical probe-pad locations, so each person's IC can be probe-tested in the same pass.

This kind of technique was done about 35 years by a company called Orbit Semiconductor.

https://en.wikipedia.org/wiki/Orbit_Semiconductor?wprov=sfla1