Uncertainty surrounding US President Donald Trump's tariff policy has rattled global supply chains and triggered downward revisions in growth forecasts for consumer electronics and networking. The fallout has slowed momentum in the high-end ABF substrate segment, with the industry now pushing expectations for a recovery to 2026.
Unimicron Chairman and CEO Tzyy-Jang Tseng said customer order visibility remains steady but cautioned that suppliers must remain vigilant amid shifting headwinds. Without the added burden of tariffs, he noted, the second half of 2025 could have marked a stronger rebound, aided by production scaling at the Guangfu and Yangmei plants.
Guangfu plant ramps early as ABF optimism builds for 2026
Unimicron's Guangfu plant in Hsinchu began mass production ahead of schedule in late 2024, focusing on high-end AI GPU applications. The site is expected to catalyze the broader ABF substrate market, with break-even projected by mid-2025, potentially outpacing the Yangmei facility.
Guangfu's monthly capacity is projected to hit 3,000 units by the end of the second quarter, increasing to 4,000 by year-end. With trade uncertainties likely to ease, Unimicron expects a resurgence in high-end demand by 2026, paving the way for a full-scale ABF recovery.
Yangmei pivots from EMIB to CoWoS to fill idle capacity
The Yangmei site in Taoyuan, co-developed with a client for embedded multi-die interconnect bridge (EMIB) technology, has cleared process verification and entered limited production. With demand falling below initial projections, Unimicron plans to reallocate idle capacity, backed by client approval, for customers adopting CoWoS advanced packaging.
Once fully operational, CoWoS-related output is expected to comprise over half of Yangmei's capacity, with full utilization likely by year-end, positioning the site to join Guangfu in turning a profit. As Unimicron's first large-scale smart factory, Yangmei delivers a 30% capacity boost and ranks among the most advanced PCB production sites worldwide.
Yangmei is equipped with cutting-edge process technology and enhanced automation, including cleanroom-based autonomous vehicles and robotic arms, to reduce manual transport risks while streamlining labor and operational costs.
US entry weighed amid capacity buildup in Asia and Europe
On the prospect of a US manufacturing footprint, Tseng noted rising client interest following new fab announcements from Amkor and ASE's Siliconware in Arizona. While Unimicron's Thailand site contributes less than 2% of revenue from direct US shipments, the American market remains strategic, and a US facility remains under active consideration.
Tseng acknowledged major hurdles to entering the US, including high water and power requirements, stringent environmental regulations, and steep labor costs—factors that would necessitate extensive investment in smart manufacturing.
Unimicron's offshore manufacturing remains centered in China, supporting substrates, PCBs, HDI, and flexible boards. The firm also operates plants in Germany, Japan, and Thailand, serving global PCB and HDI demand.
The new Thailand fab is set to begin volume output later this year, initially producing boards for gaming consoles and LEO satellites. The company may consider shifting ABF production offshore if customer requirements evolve.
In 2024, substrates generated 61% of Unimicron's total revenue, while PCBs and HDI contributed 38%. Flexible boards and RF components accounted for the remaining 1%.
Article edited by Jack Wu
