TSMC's Recycled Electronic-Grade Isopropanol Reduces Carbon Footprint by 9.7%

To achieve its vision of zero waste through resource circulation, TSMC has launched the Electronic Grade Chemicals Recycling Program. This initiative aims to transform waste generated from manufacturing processes into products that meet quality standards for reuse within the factory. Building on the development of electronic-grade Tetramethylammonium Hydroxide (TMAH) and Cyclopentanone, TSMC further collaborated with suppliers to create a dual-cycle recycling mechanism for Isopropanol (IPA) waste. This effort successfully regenerated electronic-grade Isopropanol and purified and separated wastewater generated during the recycling process for reuse in cooling towers, establishing a cradle-to-cradle green recycling system. In January 2025, Fab 15B introduced the use of electronic-grade Isopropanol, expected to reduce the annual procurement of new liquid by 2,400 metric tons and carbon emissions by 486 metric tons, marking an innovative milestone in resource recycling.

Optimizing Distillation Column Process Parameters Enhances Quality and Reduces Carbon Emissions

Isopropanol possesses excellent solubility, rapid volatility, and degreasing capabilities, making it widely used in various cleaning operations within semiconductor processes. However, due to the complex composition of its waste liquids, achieving the purity required to meet the stringent specifications of semiconductor processes after regeneration is challenging. As the demand for isopropanol continues to rise with the advancement of cutting-edge processes, in 2019, TSMC partnered with suppliers to research electronic-grade isopropanol technology to enhance environmental friendliness and increase the reuse value of waste liquids. Impurities present in the waste liquid can lead to metal leaching, affecting the purity and performance of the distilled electronic-grade material. Consequently, TSMC's Corporate Analytical Laboratories, along with the Chemical Laboratory, not only assisted suppliers in improving impurity testing and analysis methods but also conducted Design of Experiments (DOE) tests on the distillation process waste. TSMC identified key variables affecting distillation efficiency, aiding suppliers in optimizing distillation process technology. By repeatedly adjusting parameters such as tower temperature, pressure, reflux ratio, and fraction extraction, the Company found the optimal operating conditions to enhance impurity separation in the distillation tower. This effectively removed acid mixtures and metal ions from waste liquids, meeting electronic-grade reuse standards, and reduced the carbon footprint by approximately 9.7% compared to the current propylene method.

TSMC Collaborates with Suppliers to Develop Electronic-Grade Isopropanol

TSMC adheres to the principles of minimizing waste generation, maximizing resource recycling, and optimizing vendor management to evaluate the implementation of electronic-grade isopropanol recycling technology at the Taichung Zero Waste Manufacturing Center by 2026. This initiative includes developing new waste liquid recovery production lines. TSMC also continues to collaborate with suppliers to research new technologies for purifying waste solvents, phosphoric acid, and hydrofluoric acid into electronic-grade materials, thereby enhancing the value of resource regeneration.