TSMC Longtan Expansion Revived as 1.4 nm Fab Plans Return to the Table
TSMC could significantly expand its next generation semiconductor footprint in Taiwan after the long delayed Longtan Science Park Phase 3 project moved forward again following a major change in local sentiment. According to Liberty Times, supply chain sources indicate that TSMC is considering 2 A14 1.4 nm fabrication plants and 1 panel level advanced packaging facility at the expanded site. The configuration has not been officially confirmed by TSMC, and the final manufacturing plan remains under evaluation.
The Longtan expansion originally became controversial because approximately 88% of the proposed land was privately owned. Local opposition eventually led TSMC to announce in October 2023 that it would no longer consider the Phase 3 site under the conditions at the time. Since then, the Hsinchu Science Park Bureau and Taoyuan City Government have continued discussions with residents and landowners. The project was initially reduced from 158.59 hectares to 89.63 hectares, but later expanded again to 104.19 hectares after some residents and landowners requested a larger development area and opposition began to soften. Around 46 hectares are currently planned for industrial use.
The renewed plan passed the Science Park review process in May 2026 and was submitted to Taiwan's Executive Yuan in June. It is currently under review by the National Development Council. If approved, the project must still complete environmental reviews, land conversion procedures, and property acquisition before construction can begin. Authorities are targeting the end of 2029 to complete the necessary land procedures, with infrastructure development and industrial leasing expected to begin in 2030. The revised project is estimated to create around 6,200 jobs and approximately NT$310 billion in annual production value. TSMC has indicated that it would be interested in entering the site if the required procedures are successfully completed.
Longtan could therefore become an additional part of TSMC's rapidly expanding A14 manufacturing strategy rather than replacing its existing plans. TSMC is already advancing a major 1.4 nm manufacturing complex in Taichung, which we previously covered in our report on the company's A14 expansion in Taiwan. Construction at the Central Taiwan Science Park is progressing, with the facility planned around multiple fabs and production targeted for 2028.
TSMC officially introduced its A14 process technology in 2025 and plans production for 2028. Compared with N2, the company says A14 can deliver up to 15% higher performance at the same power, up to 30% lower power consumption at the same performance, and more than 20% higher logic density. The process is being developed for demanding AI, high performance computing, and mobile applications, making additional production capacity increasingly important as customers prepare future generations of advanced processors.
The Longtan reversal highlights just how strategically valuable advanced semiconductor manufacturing has become for local economies. What was once a heavily contested expansion is now moving forward again as communities see the employment, infrastructure, and economic activity generated around Taiwan's other major semiconductor hubs.
For TSMC, Longtan could provide valuable additional capacity as A14 demand grows, while combining advanced logic manufacturing and next generation packaging within the same regional ecosystem. The important detail is that the reported 2 A14 fabs and packaging plant remain a supply chain proposal rather than an officially confirmed TSMC production plan. If the project clears its remaining regulatory and land acquisition hurdles, however, Longtan could once again become one of the most important locations in Taiwan's future semiconductor roadmap.
Do you think TSMC should continue concentrating its most advanced manufacturing in Taiwan, or should more A14 capacity eventually be distributed across its international fabs?
