At what size of transistor does semiconductor manufacturing become practical for independent manufacture?
Currently, only one company in the world -- ASML -- has the technological capability necessary for the creation of photolithography machines which are sufficient for the production of modern semiconductor devices. What I'm wondering is at what point does semiconductor manufacturing become practical, or even feesible for small organizations, or independents? One must be able to surpass the cost of the machines, and the resources necessary to manufacture them. I presume that a company like ASML is also extremely picky -- willfully, or by regulation, or otherwise -- about who they lend their technology to.
I'm not sure if this is the right community for this sort of post. Please let me know if not, and if there is a more suitable place to put it.
There is an answer but you'll probably only manage to get it by going through semiconductor devices history and determining the hardware required at each improvement step, and the cost and acquirability of that hardware. This would take hours - potentially days - of research.
A quick search yielded this blog post though of someone attempting - and managing - production of a basic 1200-transistors semiconductor device in their garage, which I found rather neat. That's with no cleanroom, and with chemicals the purity of which are far removed from the ones the industry uses.
We've had open-source chip design software since the 1980s. Magic VLSI, for example. There are quite a few OSS tools for various parts of the chip design process.