A semiconductor factory under construction outside Phoenix just got $5 billion bigger.
Amkor Technology is expanding its advanced chip packaging and testing campus in Peoria from a planned $7 billion investment to about $12 billion. The reason is unusually simple: customers have already committed to more capacity than the first phase was designed to provide.
The expansion announced Sept. 8 will add 60,000 square meters of cleanroom space, bringing the campus to about 93,000 square meters, roughly 1 million square feet. Together, the two phases are expected to employ more than 3,500 people in Arizona…