AMKR Stock Gains After-Hours — Amkor Doubles Down On US Chip Manufacturing With $12B Arizona Campus Expansion

Amkor Technology is boosting its capital footprint in Arizona with a massive Phase 2 expansion driven by soaring customer demand.

• Phase 2 will add 60,000 square meters of cleanroom floor space, bringing total advanced packaging and testing space to about 93,000 square meters. 
• Total projected capital spending grows to around $12 billion, with expected local employment topping 3,500 jobs. 
• Construction on the second phase is slated to begin in late 2027, with target completion set for the end of 2029. 

Semiconductor packaging firm Amkor Technology Inc. (AMKR) announced on Tuesday that it is significantly expanding its footprint by launching Phase 2 of its Arizona manufacturing site and raising its total commitment in the region to about $12 billion.

The decision stems from overwhelming market demand that quickly eclipsed the initial capacity planned for the first phase of the development.

Arizona has rapidly transformed into a premier domestic microchip hub, hosting major fabrication plants and facilities from industry leaders including TSMC (TSM), Intel Corp. (INTC), ON Semiconductor (ON), and NXP Semiconductors (NXPI).

Expansion Spurred By Soaring Demand

Amkor’s initial Phase 1 buildout was designed to deliver 33,000 square meters of cleanroom operations. But early customer orders pushed the semiconductor assembly and test services provider to roll out a second phase ahead of schedule.

Phase 2 will contribute an additional 60,000 square meters of high-tech production space. Once both buildouts are complete, the Tempe-headquartered company will operate approximately 93,000 square meters of cleanroom space across its 170-acre campus.

"This next phase reflects the confidence our customers have placed in Amkor, the critical role advanced packaging plays in enabling the future of semiconductor innovation, and the strategic importance of our Arizona campus," Kevin Engel, Amkor’s president and chief executive officer, said in a statement.

Anchoring The US Semiconductor Chain

The project represents the first large-scale domestic OSAT (outsourced semiconductor assembly and test) hub in the United States. It provides American fabless designers and device makers a complete end-to-end onshore manufacturing ecosystem, including wafer bump, probing, assembly, and final testing services.

The domestic focus aligns with broader industry movements to shorten supply chains and insulate advanced technology production against geopolitical disruptions.

When operational, the multi-phase site is expected to house more than 3,500 employees, forming a crucial node in Arizona’s rapidly expanding microchip belt.

Development on Phase 2 is targeted to break ground in late 2027, with initial completion slated for the end of 2029.

Company executives noted that the footprint of the 170-acre Tempe property leaves room for further modular additions beyond Phase 2 should customer demand continue to surge.

AMKR Stock: Retail View 

Retail sentiment on Stocktwits was ‘bullish’ with ‘high’ message volumes. 

One user lauded the surge in customer demand. 

View this Stocktwits post

AMKR stock has gained 26.2% year-to-date. 

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