Jeri Ellsworth has gone "deeper" into the process and made a few transistors, although at a much larger scale:

https://www.youtube.com/watch?v=w_znRopGtbE

https://www.youtube.com/watch?v=-Qph8BNrnLY

To me this is far more impressive than any of the other stuff posted here. It's actually doing it rather than talking about it or faking the first 99.9% of it.

Did he do his own etching? I'd say buying blank wafers would be a perfectly reasonable place to start, but if you're buying printed wafers, then you might as well buy the whole chip.

Yeah, I don't think people will be pulling pure silicon crystals at home any time soon.

That’s actually quite doable in a garage, assuming you are satisfied with, say, two inch wafers. (Currently, they are approaching 18 inches!)

It’s much easier to produce silicon ingots than to do wafer fab, because of the currently tiny line widths.

But, it would make more sense to simply buy wafers (or epitaxial wafers).

If they do, I imagine they’d leave it at that instead of going on to make a chip.

I believe he bought them with the gates etched & fets doped, and did his own metal. Something like that.