In the early hours of January 21, a powerful 6.4-magnitude earthquake hit Chiayi, Taiwan, forcing leading semiconductor manufacturers—TSMC, UMC, and Innolux—to implement precautionary shutdowns of their production lines. In response, teams of engineers were swiftly mobilized overnight to evaluate the damage and restore production efficiency.
The recovery process, which includes equipment inspections, cleaning, and recalibration, is expected to take several hours, with potential production defects anticipated. Industry analysts estimate a minimum production loss of half a day, which is likely to be covered by insurance.
Seismic impact on semiconductor facilities
According to industry regulations, semiconductor facilities must shut down if an earthquake of magnitude 4 or higher occurs. The recent 6.4-magnitude earthquake in Chiayi was classified as an ultra-shallow event, occurring at a depth of just 9.7 kilometers, with a peak intensity of level 6 (lower). In Tainan, 26 aftershocks were recorded within 90 minutes, with the strongest reaching magnitude 5.2.
In the Southern Taiwan Science Park (STSP), the earthquake registered at intensity level 5, triggering precautionary shutdowns across various facilities. Equipment inspections, projected to last 4 to 6 hours, are ongoing and expected to continue through the morning of January 21.
TSMC's advanced manufacturing processes have garnered the most attention among the affected companies, as stakeholders closely monitor the impact on production timelines.
Seismic monitoring systems measured ground accelerations of 84.90 Gal (intensity level 5 lower) in Tainan Science Park, while Kaohsiung Science Park recorded 31.20 Gal (intensity level 4).
Facility-specific seismic sensors reported higher accelerations in Tainan, with Innolux's Fab 3 recording 143.00 Gal (intensity level 5 upper), TSMC's Fab 18 at 105.00 Gal, UMC at 131.00 Gal, and HannStar Display at 126.80 Gal—all classified as intensity level 5 lower. In Kaohsiung, Innolux's Fab 8 recorded a ground acceleration of 35.00 Gal (intensity level 4).
Operational status and safety measures post-earthquake
The STSP Bureau confirmed that major manufacturers took precautionary measures by shutting down equipment and evacuating personnel. Fortunately, no injuries or casualties have been reported.
Essential utilities, including water, electricity, and gas, along with wastewater treatment plants, public buildings, and construction sites, were not affected by the earthquake. As a precaution, elevators in factory buildings and dormitories were automatically deactivated.
By the morning of January 21, personnel at major STSP facilities had resumed work. Assessments of equipment malfunctions are ongoing, and the overall impact and recovery timeline are still being determined. Fortunately, no injuries, fires, or chemical leaks have been reported. Water and power supplies remain stable, with no damage to public infrastructure.
TSMC's emergency response
TSMC reported that several of its fabs in the Central and Southern Taiwan Science Parks met the evacuation threshold. Prioritizing employee safety, the company activated emergency response protocols, carrying out both indoor and outdoor evacuations along with thorough personnel headcounts.
Innolux's recovery efforts
Innolux confirmed that it promptly implemented standard safety procedures, ensuring the well-being of its employees. Staff at Tainan sites meeting the evacuation threshold were safely relocated, and the company has initiated support initiatives for employees living near the Chiayi-Tainan border.
As a precautionary measure, some equipment at the Tainan plant was automatically shut down. Following building safety assessments, technical teams have commenced system inspections, and operations are gradually resuming.