Comparative life cycle assessment of hybrid bonding and copper pillar die-to-wafer 3D integrations for sub-THz applications

According to IPCC
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, “global warming is likely to reach 1.5°C between 2030 and 2052 if it continues to increase at the current rate“ [1]. Meanwhile, global data traffic continues to rise significantly [2], spurring the development of next generation communication systems. Therefore, it is critical to quantify and decrease environmental impacts of new technologies starting from R&D stage before industrialization. This study aims at comparing die-to-wafer (DtW) 3D interconnection technologies (hybrid bonding and copper pillar) required for 6G application using Life Cycle Assessment (LCA). This study is carried out on CEA-Leti R&D assembly process of silicon dies on $300 \mathrm{~mm}$ silicon wafer with CEA cleanroom data. Results show that hybrid bonding has 1,3 to 2,1 more impacts than copper pillars on relevant selected impact categories in R & D scenario and almost similar impacts in prospective industrial scenario. Future investigations are needed to consolidate results, including whole life cycle.
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IPCC: Intergovernmental Panel on Climate Change