Imec, a leading research and innovation hub based in Belgium, has made a breakthrough in reducing carbon dioxide emissions in chip factories through an advanced lithography technique. The company showcased its sustainable alternatives and practices during the 2024 Advanced Lithography + Patterning Conference, highlighting the need for innovative solutions in reducing the carbon footprint associated with lithography and etch processes.
Lithography is a crucial step in the manufacturing of integrated circuits or semiconductor chips. It involves using light to transfer a pattern onto a substrate, typically a silicon wafer. Imec’s new technique aims to significantly reduce the emissions associated with lithography and etch processes in semiconductor fabrication, which currently contribute over 40% of direct emissions in advanced logic node Scope 1 and Scope 2 categories.
According to Imec’s research, semiconductor devices produced in 2021 generated a CO2 equivalent footprint of about 175 megatonnes, equivalent to the yearly emissions associated with approximately 30 million people. Imec’s alternatives focus on simplifying the dry etch processes used in chip manufacturing while maintaining high-quality semiconductor fabrication. The goal is to minimize the environmental impact of these processes.
To demonstrate the emissions impact of lithography and etch processes, Imec developed a virtual fab model called Imec.netzero within its Sustainable Semiconductor Technologies and Systems program. This model played a pivotal role in showcasing the contributions of these processes to Scope 1 and Scope 2 emissions, emphasizing the need for sustainable solutions.
Imec proposes several directions for future patterning, including the use of ultra-thin resists and underlayers, minimal passivation, and low process temperatures for etch. The company also showcased a High-NA-compatible metal line etch process that resulted in a significant reduction of approximately 94% in process gas emissions.
One of the main challenges in lithography is the emissions associated with electricity generation. Engineers have been exploring greener energy sources, reducing multi-patterning steps, minimizing photoresist dose, and enhancing scanner throughput for improved energy efficiency.
Emily Gallagher, a principal member of the technical staff at Imec, expressed the company’s commitment to sustainability and its satisfaction in seeing sustainability gaining importance in the industry. She highlighted the increasing number of papers on sustainability at the conference, with Imec alone contributing four out of the anticipated 45 papers in the sustainability track. Gallagher emphasized the urgency of taking action to address climate change, especially in light of recent record-breaking global climate events.
Imec’s initiatives in process innovation and sustainability align with the broader industry shift towards eco-friendly semiconductor fabrication. As companies recognize the importance of reducing their carbon footprint, research and development efforts like Imec’s are crucial in driving sustainable practices in chip manufacturing.
In conclusion, Imec’s advanced lithography technique offers a climate-friendly solution to reduce CO2 emissions in chip factories. By focusing on sustainable alternatives and practices, Imec aims to minimize the environmental impact of lithography and etch processes while maintaining high-quality semiconductor fabrication. This breakthrough reflects a larger industry trend towards eco-friendly semiconductor manufacturing and highlights the importance of sustainability in technological advancements.