Many years ago I worked on an electron beam lithography system that was a converted electron microscope. You need to control the X/Y position of the beam and need some sort of shutter/deflection mechanism which should be within the realm of what a very dedicated hobbyist or group can do. I wrote the software and designed some hardware. I wonder if you could pick up an old electron microscope for cheap somewhere if that would be a starting point for a home made chip fab ;) probably too many difficult parts though, wafers, resist, bonding, packaging, clean room etc. But who knows, sometimes these things can be done on the cheap if you're willing to make some compromises...
But here's another idea, if you live close to a university that teaches semiconductor physics or chip design check with them, the system I worked on was used by graduate students and for general research...
I don't think any fab will talk to you. A "real" chip is usually millions of dollars even for older processes.
If you don't care about the actual fabrication then you can use programmable logic like FPGA and get something very close to an actual chip design running on an actual chip. You can probably just get a design to run in a simulator ...
If you can couple up with a local academic institution, and get them to submit your chip as a research or teaching project, MOSIS will fabricate your chip for free [1]. They will package up to 5 chips, though it's not clear whether the user or MOSIS pays that cost.
But here's another idea, if you live close to a university that teaches semiconductor physics or chip design check with them, the system I worked on was used by graduate students and for general research...
I don't think any fab will talk to you. A "real" chip is usually millions of dollars even for older processes.
If you don't care about the actual fabrication then you can use programmable logic like FPGA and get something very close to an actual chip design running on an actual chip. You can probably just get a design to run in a simulator ...