The role of circular strategies in improving material efficiency and reducing environmental impacts of semiconductor manufacturing

As semiconductors have evolved into an integral part of modern societies, enabling wide range of applications from consumer goods to embedded systems, the environmental impacts caused by the semiconductor industry have become significant as well (Wang et al., 2023). Due to the alarming need to
minimize the consequences of climate and environmental crisis, the industry must reduce its emissions effectively. Simultaneously, the semiconductor industry seeks to improve its resilience to avoid disruptions in supply chains to have a solid foundation for global competition (European Chips Act, 2024; CHIPS and
Science Act, 2022). Circular economy has potential to reduce environmental impacts of semiconductor manufacturing as recycling and recovering materials decreases the need for extracting virgin materials, which also reduces external dependencies of the industry and improves resilience. Where greenhouse gas
emissions of the semiconductor industry have gained more attention in the last years, little research has been done regarding the potential of circular practices.

In this study, the focus was on circular practices in the semiconductor industry with the emphasis on material recovery. The impact of integrating material recovery processes in semiconductor manufacturing was assessed using the life cycle assessment (LCA) method. The objective of this study was to form a comprehensive view of industry’s current practices related to circularity, to have an overview of potential new solutions based on existing literature, and to analyze potential challenges and bottlenecks related to implementation of these new measures.

As an example of potential circularity measures, the LCA case study compares traditional chemical mechanical polishing (CMP) process step during semiconductor manufacturing with an industrial test configuration where the CMP slurry is recycled. The LCA study follows the Product Environmental Footprint (PEF) and the EF 3.1 impact assessment method, while circularity hotspots are assessed applying well-known circularity indicators, such as the Circular Transition Indicators. Additionally, the role of circular solutions in material recovery within the semiconductor manufacturing is examined by analyzing sustainability reports of major semiconductor companies and making literature review of emerging methods for material recovery.

Moreover, the results of this study are utilized for creating a circularity roadmap for the Finnish semiconductor industry, together with industrial actors. The opportunities and challenges identified aim to guide companies to improve their material efficiency, and to integrate principles of life cycle thinking.