The environmental impacts of electronics. Going beyond the walls of semiconductor fabs

The growing complexity of integrated circuits and increasing component density place higher requirements for raw material and clean room standards, which demand significant amounts of energy. In spite of these developments, semiconductor facilities managed to reduce their energy intensity measured per product unit. At the same time, the impact of increasing circuit integration on upstream life cycle stages, such as chemical manufacturing, is not clear. Due to a lack of data, most of the existing LCA studies do not include chemical-related processes into their system boundaries, which leads to an incomplete picture of semiconductor environmental aspects. The increasing material purity requirements may contribute to shifting the centre of manufacturing-related environmental impacts from circuit fabrication to raw material production stages. This article points to insufficient knowledge of environmental issues related to ultra-pure chemical manufacturing. The problem is illustrated by an example of energy demands for the silicon chain and wet chemicals. The paper discusses the feasibility of using material price as a proxy for production energy intensity and proposes a framework for collecting process related energy data. The author suggests that by mapping the patterns of chemical usage and focusing on high-grade materials consumed in large volumes it is possible to reduce data collection efforts and improve the existing energy estimates.