[rrss]

One supplier: skywater.

In 1990, Cypress Semiconductor acquired a Control Data fab, which became Cypress Fab 4. At some point they developed a 130nm process. In 2017, cypress sold the fab to skywater, which was formed specifically to operate this fab. Skywater, google, and efabless collaborated to publish the PDK for the 130nm process.

“Old” processes like this have lots of uses, even before the recent supply chain issues (which were/are often worse for mature processes than more leading edge stuff). They are commonly used in automotive / embedded stuff, and the US government / military require US-based semiconductor fabrication for some contracts.