> HK has a number of abandoned fabs built up to nineties technology level. They were once built by no name electronics companies in nineties, but they all went bust during the Asian crisis.

This is __absolutely__ the most cyberpunk thing I've read all year. Truly, we live in the future.

A question arises - how much work would it actually be to bring up a fab that's been dead for several (much less a dozen) years? Wouldn't the fab basically need to be ripped apart and completely refurbished by now? Or are the most important pieces fairly immune to physical degradation when abandoned without regular ongoing maintenance?

Quite a lot, but still incomparable to doing it from scratch. FAB require very unique equipment, not used in any other industry. Like water filtration plants that can make ultra pure deionised water in tenths of cubic metres per hour, process gas recycling plants, industry specific automation equipment, etc

Even a nineties tech level, a FAB still costs a megaton of money.

The most unique proposition here is that a prospect of getting an actual FAB with a lot of automation, and not a laboratory coaxed into manufacturing role is within the grasp. You can't have that anywhere else in the world.

I don't have any knowledge, but wouldn't running an ancient full-scale commercial fab academically/for small volumes be very uneconomical even if they got the fab itself for free.

Even 600nm is commercially viable for specialty applications, 300nm for low-end general purpose, and their aim is 180nm. So there is nothing about the process itself that disqualifies it.

Heck, with immersion lito you can even use DLP chip(s) with 405nm and then-trivial multi-patterning to the 180nm... likely even close to 130nm, but that's a stretch that might be too hard on the compensation. This sort of node, with no minimum order quantity and pricing within 2~5x of mask-based fab (slightly slower steppers at these scales, but 600nm might be still reachable in 2 minutes on a 12" for the exposure if you use some resonance or so to get sawtooth-motion of the head to e.g. compensate for a spinning wafer (think like a record/CD player unless viewed in slow motion). Resonance is surprisingly easy to keep steady-state with just a piezo and maybe another one if needed that provides all high frequency content that's not handled by the fundamental and 2 or 3 low harmonics of the scan frequency.

There are applications thanks to modern automation as far as hard-wired logic instead of a via mask ROM, and this should be able to eat much of the low-end FPGA business due to even just much higher design flexibility.