TSMC adheres to its commitment to the management of hazardous substances to ensure that the chemicals used in the process fully comply with international regulations and customer requirements. In 2016, the Company led the domestic industry to launch a reduction plan for the hazardous chemical N-Methyl-2-Pyrrolidone (NMP). In October 2022, TSMC successfully completed the tool modification and alternative process verification and reached the annual target of "95% reduction in NMP usage" set in the Sustainability Report, reducing the carbon footprint of about 7,800 metric tons of carbon dioxide equivalent per year and continuously improving the green manufacturing capability.

Hazardous Substance Management Cycle Mode, Cross-fab Collaboration for NMP Reduction

TSMC’s hazardous substance management system is based on the QC 080000 Hazardous Substances Process Management (HSPM) system. This system is predicated on protecting human health and reducing environmental impact, adhering to the principle of (1) avoiding use if possible (2) using less if possible, according to the Plan-Do-Check-Act management cycle mode to continuously improve the use of hazardous substances.

In view of the chemical NMP commonly used in the industry, TSMC mainly uses it as a solvent for cleaning wafers after the photoresist stripping process. In order to reduce the risk of personnel exposure and environmental contamination, TSMC exceeded the regulatory requirements, and voluntarily conducted the "NMP Replacement Program for Photoresist Stripping Wet Cleaning Process" in 2016. Advanced process below 7nm (inclusive) completely exclude the use of NMP, and existing fabs are gradually replacing NMP with the goal of the fabs in Taiwan reaching 100% NMP replacement in 2030.

Through close collaboration with customers, TSMC's Engineering Department, Manufacturing Department, Process Integration Department and Wet Etching Technical Board not only evaluated the alternative chemical for the process but also modified the equipment hardware and process parameters during the replacement process without affecting the product yield. After many formulation adjustments and repeated testing to achieve process optimization, through cross-fab collaboration, we completed photoresist stripping wet cleaning process equipment modification in October 2022, and set up the maintenance mechanism of the equipment to ensure the quality of subsequent production.

Comprehensive hazardous substance management is an important element of TSMC’s ability to improve quality. TSMC will further promote the implementation of NMP reduction plans in overseas fabs, and conduct feasibility assessments for the replacement of the small amount of NMP-containing photoresists in order to achieve the long-term goal of 100% non-use of NMP, protecting the safety of employees and industrial supply chains, and promoting environmental sustainability.