Nvidia has agreed to give Amkor Technology a $1.5 billion prepayment to expand advanced semiconductor packaging and testing in the United States, tightening a supply relationship that already sits behind its data-centre chips.

The agreement, announced on 23 July, pushed Amkor shares up by roughly 12% in after-hours trading.

Packaging is the least glamorous stage of chipmaking and, lately, one of the most contested. It is the step where finished silicon is stitched together with memory and interconnects into the dense modules that run AI servers, and demand for that work has run well ahead of the capacity to do it.

The constraint is not abstract. Shortages of advanced packaging, rather than raw wafer fabrication, have at times been the factor limiting how many AI accelerators Nvidia can ship. That makes locking in the capacity a strategic priority rather than a procurement footnote.

Nvidia has spent the past year turning scarce inputs into guaranteed ones. A warrant-backed deal with Corning brought new US plants and thousands of jobs into its orbit, and it recently locked in SK Hynix for HBM4 memory.

The Amkor prepayment applies the same logic to the back end of the production line.

Under the arrangement, the money will fund the expansion of Amkor’s operations in Arizona, where the company is already building a $2 billion packaging and test facility in Peoria.

The prepayment is not an equity stake. It is cash committed upfront against future capacity, a structure that lets Amkor build ahead of demand it might otherwise hesitate to fund alone.

Nvidia has increasingly used its balance sheet this way, spreading prepayments, warrants, and direct commitments across suppliers to secure the inputs its roadmap depends on.

The two companies said they would jointly develop packaging and test technologies for what they described as next-generation AI and accelerated-computing platforms.

That work includes high-density interconnects and heterogeneous integration, the practice of combining different types of silicon, logic, memory, and more, inside a single package.

“AI is driving a generational shift in technology, transforming every industry and creating a unique opportunity to reinvigorate American manufacturing and supply chains,” said Debora Shoquist, Nvidia’s executive vice-president of operations.

Kevin Engel, Amkor’s chief executive, said the partnership “underscores the central role advanced packaging plays” in the future of AI.

The deal lands on top of an already crowded year for Amkor. The company packages chips for both Nvidia and AMD, and in June signed a 10-year agreement with TSMC for advanced packaging in Arizona.

It has supplied packaging for Nvidia’s data-centre processors for some time, so the new commitment widens existing work rather than starting it.

That run of deals has turned a once-obscure outsourced assembler into one of the more sought-after names in the American chip build-out.

Both sides framed the expansion as a hedge as much as a capacity play. Concentrating packaging in a handful of Asian sites has long been a single point of failure for the industry, and a domestic alternative is meant to give the AI supply chain more geographic resilience.

The Arizona expansion fits a broader onshoring push. Amkor’s Peoria plant was awarded $407 million under the CHIPS and Science Act, and it sits close to TSMC’s Arizona fabs, whose wafers it is well placed to package without shipping them back to Asia first.

Keeping fabrication and packaging within the same state closes one of the last gaps in a domestic supply chain that policymakers have spent years and billions trying to assemble.

Most advanced packaging capacity still sits in Asia, and reproducing it in the US is slower and dearer. Nvidia’s suppliers have been moving regardless, from a Texas factory assembling Grace Blackwell systems to a run of domestic commitments announced since the start of the year.

Neither company disclosed a timeline, or how much fresh capacity $1.5 billion actually buys. Amkor’s share price suggests investors were not inclined to wait for the details.

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