LIM, T. G., Ching, E. W. L., Tippabhotla, S. K., Feng, H., & Wu, J. (2025). Backside Metal Interconnect for High Performance RF Interposer. In (Editor), 2025 IEEE 27th Electronics Packaging Technology Conference (EPTC). https://doi.org/10.1109/eptc67330.2025.11392658
Abstract:
This paper presents a robust integration design for high-power, high-frequency, and high-reliability 2.5D Silicon interposers. The proposed approach utilizes an interface Cu-Mo shim which has high-thermal and electrically conductive and matching CTE between the interposer and the substrate/PCB. The high thermal conductive Cu-Mo helps to provide low thermal resistance path from the interposer backside to the thermal solution in the substrate/PCB. The high electrical conductivity Cu-Mo helps to replace the Ground solder ball and at the same times further improve the thermal performance. The RF transition is designed by optimizing the opening dimension of the Cu-Mo shim for operating frequency up to 50GHz. The matching CTE helps to improve the solder joint reliability of the solder ball by more than 50%.
License type:
Publisher Copyright
Funding Info:
This research / project is supported by the DSO-SHINE - A*STAR
Grant Reference no. : Grant No. I2101E0008