Home-made SSI chips

Hi all!
Please don't laugh.. I'm serious.

After having made PCB's with the photographic-like technique, and
being very pleased with the resolution I've been able to achieve,
I was wondering what would it take to make my own SSI chips?

Of course I'm not talking about 90 nM resolution.. but something
like 0.1 millimeters (at best). I have a 2400²dpi laser printer.

How does one make a transistor? Is this technology reachable from
the (enthusiast) hobbyst? Where could I find the necessary materials?

Thanks!
John