[derefr]

Why is it so hard to horizontally scale a working chip fab (i.e. copy-and-paste the entire plant to get more throughput)?

Is it a bottleneck on staffing people with the required expertise (i.e. are the only people who can run a given process node, the same people who designed/operationalized that process node)?

[d_silin]

I read somewhere that scaling semiconductor fabs is incredibly difficult affair, as every minute detail have to be faithfully replicated - down to using the same color of lighting. All that is required to get consistent output quality.

[jamiek88]

You even need identical seismic environments it’s that delicate.

[derefr]

Seems like the best idea would just be to try to plop the new plant next-door to the existing plant, then (and to keep doing that.) Would make the logistics of sourcing the same "everything" a lot simpler.

Intuitively, I'd expect that fabs would plan for this in advance, ensuring that 1. everything they buy, they have ways to get N of the exact same of that thing down the line — the same way that NASA missions contract to ensure they can get precisely-specced replacement parts decades down the line; and 2. that they build their first plant for a given process node in a huge empty expanse of land (much larger than what Plant No. 1 needs) where they either buy all that land ahead of time, or at least have a contract with the municipality to retain right-of-first-refusal on purchases of that land.

[Macha]

There's also a long lead up time to opening up a new fab. If you have just proved out your process, it might be tempting to duplicate that but when you're chasing the cutting edge as these markets are, there's a real opportunity cost to consider in scaling out your now "mature" process vs chasing the next big leap.

Maybe now that there are only two players left and new process costs continue to escalate we might see more of that

[LdSGSgvupDV]

Despite the people, water, and electricity are another issues.

Taiwan is a small country with limited water resource due to the lack of land to have long river to keep the water on the ground.

For the electricity, nowadays, many BIG TECHs demand "green" electricity to manufacture their products, but once again Taiwan is not a big country. There is no enough area to hold the solar plates and the weather there is not suitable for wind power because of the typhoon.

These are the nature limitations. There are also other issues such as lack of engineers, the risk if expansion is not worth it in the future, etc.

[derefr]

IIRC a solar farm is being built in Australia which isn't going to touch Australia's own power grid, but rather is going to connect to Singapore's power grid using a pair of undersea HVDC cable runs.

Taiwan could probably get in on that action. If you're already running a 3500km cable, you could run a 4500km cable just as well.

(Kind of annoying that Taiwan can't just buy green energy from China — very easy logistically — but that's extremely politically untenable.)