[News] ASE’s SPIL Reportedly Nears Arizona Expansion as TSMC, Amkor Step Up U.S. Advanced Packaging Push

ASE’s U.S. expansion may be moving closer to a major step as demand for advanced packaging capacity grows. According to Central News Agency, ASE subsidiary SPIL is reportedly in the final stages of planning a new facility in Arizona, with a decision expected soon. The proposed facility could provide back-end testing services, and if finalized, would mark a key step in ASE’s U.S. expansion.

At its investor conference in late July, ASE said its process development remains centered in Taiwan for now, but it will expand into the U.S. or other regions when the timing is right. ASE has raised its 2026 capital expenditure by another US$2 billion to US$10.5 billion, including about US$4 billion for new plants and facilities and US$6.5 billion for equipment, the report notes.

SPIL is also actively expanding its advanced packaging capacity in Taiwan. Construction began in mid-August on a new plant in Douliu, which is expected to introduce CoWoS advanced packaging. SPIL said it has expanded facilities in Taichung, Changhua, Yunlin, Hsinchu, and Tainan, with total expansion investment over the past two years reaching NT$200 billion.

Notably, the report highlights that SPIL has maintained close ties with NVIDIA, while AMD has also worked with the company to develop and validate next-generation 2.5D bridge-interconnect advanced packaging technology.

Other major packaging players are also stepping up investment in Arizona. According to Investing.com, Amkor said it had raised planned investment for the second phase of its Arizona expansion from US$7 billion to US$12 billion on stronger customer demand. The Arizona campus is expected to begin production in 2028 and reach full capacity by 2030. As noted by GuruFocus, Amkor signed a 10-year agreement with TSMC in June to provide advanced packaging and testing services in Arizona, supporting TSMC’s expanding fab operations in the state.

TSMC Expands Arizona Footprint With Fabs and Advanced Packaging

TSMC is likewise ramping up advanced packaging capacity in both the U.S. and Taiwan. According to Economic Daily News, institutional investors say TSMC’s CoWoS capacity is expected to double from 130,000 wafers per month by the end of 2026 to 260,000 by the end of 2028, with expansion focused on its AP9/10 sites in Arizona and AP7 in Taiwan.

However, as surging demand tightens advanced packaging capacity, customers are actively qualifying alternative suppliers. As Economic Daily News notes, institutional investors estimate that non-TSMC players, including ASE and Amkor, will expand capacity equivalent to 110,000 CoWoS wafers per month by the end of 2028. For Intel’s EMIB-T, institutional investors estimate that 12-inch CoWoS-equivalent capacity could reach 15,000–20,000 wafers per month in 2027 and 40,000–45,000 in 2028.

TSMC announced an additional US$100 billion investment in Arizona in mid-July, including advanced packaging facilities. According to Central News Agency, its first advanced packaging facility in the state is planned to come online before 2029.

Read more

• [News] ASE’s SPIL Breaks Ground on Nearly TWD 100B Plant in Douliu to Boost CoWoS Capacity, Operations Set for 2028
• [News] TSMC Reportedly Targets 22% 2nm, 16%+ 3nm Capacity Boost by Mid-2027; CoWoS to Double by 2028

(Photo credit: SPIL)