Low-temperature bonding of Si and polycrystalline diamond with ultra-low thermal boundary resistance by reactive nanolayers

Thermal management is a critical challenge in modern electronics and recent key innovations have focused on integrating diamond directly onto semiconductors for efficient cooling. However, the connection of diamond/semiconductor that can simultaneously achieve low thermal boundary resistance (TBR), minimal thermal budget, and sufficient mechanical robustness remains a formidable challenge. Here, we propose a collective wafer-level bonding technique to connect polycrystalline diamonds and semiconductors at 200 degrees C by reactive metallic nanolayers. The resulting silicon/diamond connections exhibited an ultra-low TBR of 9.74 m2 K GW-1, drastically outperforming conventional die-attach technologies. These connections also demonstrate superior reliability, withstanding at least 10 0 0 thermal cycles and 10 0 0 h of high temperature/humidity torture. These properties were affiliated with the recrystallized microstructure of the designed metallic interlayers. This demonstration represents an advancement for low-temperature and high-throughput integration of diamonds on semiconductors, potentially enabling currently thermally limited applications in electronics. (c) 2024 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.