Yup!

Here's one in Utah: https://www.nanofab.utah.edu/

Here's one in Pennsylvania: https://www.mri.psu.edu/nanofabrication-lab

Here's one in California: https://nanofab.ucsb.edu/

Those aren't starting from sand though, so they do need some external fancy tech to survive the apocalypse - to produce their wafers.

Depends on the state, but for my alma mater (Georgia Tech) I'm pretty confident the answer is yes.

Georgia Tech has one of the best fabrication programs in the world.

I just had a look and I am not sure they are making silicon wafers. I would be surprised, there's not really any research in it, and it's costly to say the least.

Yeah, I find that rather surprising that a university lab could fabricate a practical 14 nm chip (more than just some demonstration gates), given the billions of dollars that countries have to invest to set up even 65 nm fabs.

It won't be small, but you can create PCBs pretty easily with chemical etching. I think making the silicon wafers is probably harder.

PCBs are something people can do in their garage. Integrated circuit fabrication is definitely something that requires a much more sophisticated lab such as a top university lab.