People buy 3d printers. I'm sure there would be people interested in building their own silicon chips, even if it would be a lot more involved.
I can imagine a little niche market for tools and services for that kind of production. I design electronics but I order my PCBs from jlcpcb because I can get much better product with much less hassle.
Most of the other processes can theoretically be carried out at garage-scale, as the precision is more about chemistry than dimension or scale.