TSMC makes sure our Environmental Policy is fully implemented and continues to develop air pollution prevention and control technologies. In 2020, TSMC led the industry to develop the Dual-Rotor Zeolite Concentrator Technology to reduce the emissions of Volatile Organic Compounds (VOCs) by over 95%. In 2021, TSMC took one step further, working with the Industrial Technology Research Institute (ITRI) to design an enhanced central scrubber. By optimizing the scrubber’s structural design, the scrubber is able to provide higher decontamination performance. TSMC successfully introduced the new solution to Fab 18B in October 2021, and it helped further increase the reduction rate of acid and alkaline gases by 40%. The enhanced central scrubber will be a standard design for TSMC’s new fabs as part of the Company’s commitment to green manufacturing.
Optimizing the Scrubber’s Structural Design to Reduce Emissions and Extend its Lifespan
The air pollutants that generate from semiconductor manufacturing are mainly VOCs and acid and alkaline gases. The pollutants are first separated by their sources, and . 90% of the pollutants are treated on-site, while the remaining inorganic acid and alkaline gases are sent to the central scrubber for neutralization treatment. However, it is difficult to increase the treatment efficiency because the concentration is low. Based on our own sampling and measuring data, TSMC found that acid pollutants are in three different forms: gases, droplets, and particles. Moreover, the uneven flow field in the scrubber also affects its efficiency.
In light of these issues, TSMC Facility Team worked with ITRI to launch the Central Scrubber Optimization Project in 2018, using the Two-Film Theory to establish a model that meets the actual operating parameters of the central scrubber, and decide the optimal decontamination components according to different phases of pollutants. Furthermore, the height of the tower was increased from 8 meters to 9.3 meters to retain the pollutants in the scrubber longer. At the same time, a pre-filter and self-cleaning design for particle pollutants were added to wash away particles by sprinklers. This solution not only extends the maintenance cycle of the scrubber, but also reduces the risk during equipment change-over.
Difference Between TSMC's Enhanced Central Scrubber and Traditional Central Scrubber
Advanced semiconductor manufacturing is a collection of cutting-edge technologies in various fields, and the efficient treatment of process pollutants is also an essential part. Through cooperation with TSMC to optimize the central scrubber, the chemical thermodynamics and mass transfer theory are used for precise design of removal efficiency, achieving advanced environmental protection technology with nearly zero emissions!