Gold recovery from thin film deposition facilities: environmental aspects of a novel method

This paper discusses the application of a novel system for metal recovery from Physical Vapour Deposition (PVD) production waste. The recovery process enabled by the “Palette Modular Device” (PMD) avoids the overlapping of different film materials during the production phase, thus limiting the need for chemical separation and refinement of the wasted fraction of the film layers. A description of the new methodology is provided focusing on the particular scenario of multi-layer films (including a gold layer), which are commonly employed in microelectronic contexts. Furthermore, a standard recovery practice and the novel one are compared using a Life Cycle Assessment (LCA) methodology. LCA starts from the definition of the objectives and comes to inventories of all material and energy flows related to the different process stages. Moreover, it provides an impact assessment, which identifies and quantifies potential effects on the environment that is essential information for the interpretation of the results. This research demonstrates how the novel process exhibits interesting performances on different environmental impact indicators, giving a perspective of a “green” technology.