[runako]

Not being snarky here, but what is the benefit of a chip fab in Arizona, thousands of miles from the assembly lines where the chips will be used?

I get why it would be important for niche (e.g. defense) applications, but is TSMC scale really needed?

[jgab]

The equipment in chip fabs is highly sensitive to weather and natural disasters. So sites like Arizona, Austin, Oregon are chosen due to low prevalence of earthquakes no hurricanes etc.

The fabs anyways don’t ship chips to the devices they go into, they do to a separate site where they get tested, packaged and then are sent off.

The reason to onshore this is not about scale but process capability and adding security to supply chain in case Taiwan gets in a conflict. It’s not about scale but ability to produce high yielding chips at shrinking technology size, is vastly becoming a physics problem at smaller nodes.

Reality is that Samsung and Intel could run a similar fab but their yields, efficiency and process development is lagging behind TSMC. So easier to onshore TSMC process here that help Intel learn how to speedrun transition to foundry model (producing others chip designs)

[runako]

> The fabs anyways don’t ship chips to the devices they go into, they do to a separate site where they get tested, packaged and then are sent off.

I see, but I think you are still skipping the major point that the chips need to be installed in a device to be useful. That device assembly is largely in Asia, and the US does not have the ready capacity to suddenly start assembling devices.

> not about scale but process capability and adding security to supply chain in case Taiwan gets in a conflict

> Samsung and Intel could run a similar fab but their yields, efficiency and process development

If we don't need scale, then why couldn't Intel just produce the chips inefficiently in case of conflict? Or if this is about protecting the supply chain for consumer goods as well, then I am back to my initial question about siting chip production far from the places the chips are installed into devices.

[golergka]

> chip fab in Arizona, thousands of miles from the assembly lines where the chips will be used

1. Chips have a very high $/kg density, so logistics isn't go to change unit economics a lot. 2. These assembly lines are much easier to construct than chip fabs, so if there is any reason to keep the two close, it's not going to be a problem anyway.

[runako]

> logistics isn't go to change unit economics a lot

Doesn't the shipping time matter, though? And haven't we recently seen that long supply lines are brittle?

> These assembly lines are much easier to construct than chip fabs, so if there is any reason to keep the two close

I was thinking also in terms of the scale of people required to operate them, plus the transport etc. infrastructure to keep them running. All that, and a hypothetical US factory would have labor costs 5x or higher. That would seem to make it an emergency-only scenario?

I just don't see the scenario where such a fab would make economic sense.

[827a]

These were early rumors, but I recall there being some hope that the first chips this factory would produce would be used for something made by Apple also in the United States, like the Mac Pro or something like the HomePod Mini.