Amkor Technology is a semiconductor packaging and test company headquartered at 2045 East Innovation Circle in Tempe, and it is building its first domestic packaging and test facility in Peoria. As of June 30, 2026, construction of the Peoria facility was underway, Amkor had incurred $333.6 million of construction costs, and manufacturing is expected to begin in the first half of 2028. On September 8, 2026, Amkor announced a second phase of the campus that raises the planned investment to approximately $12 billion; construction of that phase is expected to begin in late 2027, with completion expected by the end of 2029. Amkor describes itself as the world's largest U.S.-headquartered outsourced semiconductor assembly and test service provider, or OSAT, meaning it packages and tests chips for chip companies, foundries and device makers. Its executive offices, which are leased, are in Arizona and Singapore. Amkor says it started its first semiconductor business in Korea in 1968, that Amkor Electronics was listed publicly and became Amkor Technology, Inc. in 1998, and that it has operated in Greater Phoenix since 1984. As of December 31, 2025, Amkor employed 30,800 people worldwide, about 95% of them in the Asia-Pacific region, 4% in Europe and 1% in the United States; no published source gives an Arizona headcount. Worldwide net sales in 2025 were $6,707,981,000. Direct sales to Apple and Qualcomm made up 29.8% and 11.1% of those sales, and the ten largest customers 72%. As of February 12, 2026, Chairman Susan Y. Kim, members of the Kim family and affiliates owned approximately 49.4% of Amkor's outstanding common stock. Kevin Engel is president and chief executive officer; Giel Rutten held that role during the 2023 to 2025 Peoria announcements [not independently verified].
Amkor's place in the chip supply chain is the stage after a chip is made: packaging and testing it for the companies that design or manufacture it. Amkor says its planned Peoria facility will specialize in advanced packaging and test technologies for artificial intelligence, high-performance computing, mobile applications, communications, and the automotive and industrial sectors. Amkor says it chose Peoria after evaluating multiple states, citing proximity to TSMC and the chance to create an ecosystem alongside TSMC, Intel and other industry leaders, with the plant giving rapid yield feedback to U.S. wafer fabs. Its links to TSMC and Intel are specific but, so far, plans rather than operating work, since the Peoria plant was still under construction as of June 30, 2026.
TSMC: in October 2024, Amkor and TSMC signed a memorandum of understanding under which TSMC will contract turnkey advanced packaging and test services from Amkor's planned Peoria facility and use those services to support its customers, particularly those using TSMC's advanced wafer fabrication facilities in Phoenix. The companies said they will jointly define the specific packaging technologies to be used, naming TSMC's Integrated Fan-Out (InFO) and Chip on Wafer on Substrate (CoWoS) as examples. TSMC said it looks forward to close collaboration with Amkor at the Peoria facility to maximize the value of its Phoenix fabs. The memorandum is not a disclosed binding supply contract, no volumes or dollar value were published, and the release does not commit to running CoWoS in Peoria [not independently verified]. No later update on the memorandum after October 2024 was found. Apple, a TSMC customer, says it is investing in the Amkor facility and will be its first and largest customer, and that the plant will package and test Apple silicon made at the nearby TSMC fab; Apple has not published the size of that investment, and no update on Apple's role after August 2025 was found.
Intel: in April 2025, Amkor announced an agreement with Intel under which Amkor will implement Intel's EMIB assembly processes at its Korea, Portugal and upcoming Arizona manufacturing facilities, creating what Amkor calls a robust alternative source for this advanced packaging solution. EMIB is Intel's multi-die assembly technology, and Amkor says the collaboration addresses demand for heterogeneous integration solutions that support high-performance computing, artificial intelligence and other data-intensive applications. No update after April 2025 was found, and no source ties this Arizona EMIB work to a particular Intel site, or gives volumes, dollar values or a start date for it.
Amkor announced in November 2023 its plans to build its first domestic OSAT facility in Peoria, projecting an investment of approximately $2 billion and approximately 2,000 employees. On February 20, 2024, the Peoria City Council approved a development agreement for the campus, originally planned on a 56-acre parcel in the Five North at Vistancia community; under a three-way joint development agreement, the city would reimburse up to $3 million toward public infrastructure, and the terms of the amended August 2025 agreement for the new site were not found [not independently verified]. In 2024 Amkor acquired approximately 56 acres with a total fair value of $36.9 million, paying $4.2 million and receiving the rest as a non-monetary grant whose grantor the filing does not name. Preliminary CHIPS Act terms in July 2024 proposed up to $400 million in direct funding and access to $200 million in proposed loans, and in December 2024 the Commerce Department awarded Amkor up to $407 million in direct funding for the Arizona facility; as of June 30, 2026, no funds had been received. In August 2025 the council unanimously approved a land swap and an amended development agreement moving the project to a 104-acre site in the Peoria Innovation Core in north Peoria. Amkor exchanged the 56 acres for about 104 acres in December 2025 [not independently verified]. At the October 2025 groundbreaking the planned investment was $7 billion [not independently verified]. On September 8, 2026, Amkor announced phase 2 and raised the planned investment to approximately $12 billion.
Construction began in the second half of 2025, and Amkor held its groundbreaking on October 6, 2025. As of June 30, 2026, construction was underway and Amkor had incurred $333.6 million of costs related to construction of the Arizona facility; the approximately $12 billion is a planned total, not money spent. The first phase will have approximately 1.8 million square feet of space and 33,000 square meters of cleanroom capacity, which Amkor says customer commitments have already surpassed. The second phase, announced on September 8, 2026, is expected to add 60,000 square meters and bring the campus to approximately 93,000 square meters of cleanroom space; its construction is expected to begin in late 2027, with completion expected by the end of 2029. Amkor's annual report for 2025 says manufacturing is expected to begin in the first half of 2028, and no later change to that timing was found. Amkor described the Peoria site as 104 acres when it announced the move in August 2025. In May 2026 it agreed to buy approximately 67 more acres for approximately $33 million, with closing expected in the fourth quarter of 2026, according to its quarterly report for the period ended June 30, 2026. Its September 8, 2026 announcement describes a 170-acre Arizona campus that allows for further expansion, but does not say whether the 67-acre purchase has closed. Amkor's job figures have changed over time: about 2,000 under the original plan, approximately 3,000 high-wage jobs with an average annual salary of $90,000 in May 2026, and, as of September 8, 2026, a workforce of more than 3,500 Arizona-based employees that phases 1 and 2 together are expected to support. Amkor says it plans to use primarily reclaimed wastewater, closed-loop systems, and discharge with key contaminants limited to less than 40% of Peoria's regulatory limits; these are commitments for a plant not yet operating, and no water volume or permit figure was found [not independently verified].
Amkor says the Peoria campus was named the Number One Deal in North America by Site Selection magazine, which it announced in May 2026. The project also carries financial conditions and costs. The CHIPS award requires Amkor to achieve construction and production milestones, restricts certain activities, and can be reduced, terminated or clawed back, and as of the June 30, 2026 quarterly report no funds had been received. Amkor also receives state and local incentives for the Arizona facility on similar terms, but their amounts are not disclosed [not independently verified]. In its quarterly report for the period ended June 30, 2026, Amkor said it expects worldwide capital expenditures of approximately $2.5 billion to $3.0 billion in 2026, an increase it attributes primarily to construction of the Arizona facility; the filing does not state the Arizona share.
Taken together, the facts show a Tempe-headquartered company whose workforce is about 95% in the Asia-Pacific region, now building a Peoria plant meant to package chips from TSMC's Phoenix fabs for customers including Apple, and to run Intel's EMIB assembly in Arizona. Those partnerships, the $407 million CHIPS award and the more than 3,500 Arizona-based employees Amkor projects across both phases all depend on the plant reaching manufacturing, which Amkor expects for the first phase in the first half of 2028, with the second phase expected to be completed by the end of 2029.