TSMC Continues to Lead the Industry in Innovating Chemical Filter Applications and Generated NT$1.6 Billion Cost Benefit in Waste Reduction
With the evolution of advanced semiconductor manufacturing processes, the technology of Airborne Molecular Contaminants (AMC) control has become critical for wafer yield improvement. In order to reduce the chemical filter waste generated by filtering AMC, TSMC puts forward to improve the filter structure to extend the life time of AMC filter. By June 2021, a total of 3,251 tons of chemical filter waste has been reduced, which could produce about 12,028 tons of carbon emission or equivalent to annual carbon dioxide absorption capacity of 31 Daan Forecast Parks in Taipei, Taiwan. The Company has successfully accumulated more than NT$1.6 billion cost benefit in those chemical filter waste reductions.
Waste Reduction 1.0: Lifetime Extension of AMC Filter by Improving the Adsorption Efficiency Led to Effective Waste Reduction by 70%
AMC is a gaseous chemical pollutant that is deposited on the surface of silicon wafer to form a monolayer film in the environment. As the linewidth of the semiconductor process continues to shrink along with the technology advancement, the requirements for cleanliness in the production environment are becoming more and more stringent, resulting in an increase in the number of filter usage. TSMC observed the use of filters among the plants and found that the chemical filter has different adsorption capacities for acid gas, base gas and total organic carbon. Therefore, TSMC Facility Division and Material Supply Chain Management Division worked with suppliers to extend the lifetime of chemical filters by adjusting the ratio of the filter material that adsorbs total organic carbon to make the filter lifetime doubled. The chemical filter with extended lifetime has been widely used since 2018.
In order to maximize the efficiency of the filter, TSMC began to use the detachable chemical filter since 2019 to replace the original integrated and indivisible chemical filter, which has been further structured based on the different adsorption efficiency for acid gas, base gas, and total organic carbon. The restructured detachable filter can effectively reduce the risk of getting injury for filter replacement. General speaking, more than 70% of filter waste has been reduced by improving the adsorption efficiency of chemical filter and its structure.
Waste Reduction 2.0: Development of Filter Regeneration and Reuse Results in Accumulated Waste Reduction by 90%
In 2020, TSMC once again worked with suppliers to optimize the filter structure and restore the initial adsorption efficiency by physical treatment for filter reuse. The evaluation of filter regeneration was completed in March 2021. The Company will introduce this regenerative filter to all TSMC fabs in Taiwan in 2022, which will lead to the filter waste reduction by 20% a year and accumulated waste reduction by 90% in the future.
The History of Filter Development at TSMC
Note: The stacking order of the filters is for reference only
TSMC Continues to Upgrade Chemical Filter Applications
TSMC has also improved the structure of the chemical filter in Make-up Air Unit (MAU). It is expected that 35 million kWh of electricity can be saved by reducing pressure drop in 2022 through improving the filtration efficiency as well as the energy saving. TSMC will constantly move toward the sustainable goal of energy saving, carbon emission reduction, and recycling.