Ultra-fine Pitch (6 um) of Recessed and Bonded Cu-Cu Interconnects by 3D Wafer Stacking

This paper describes the development of a reliable Cu-to-Cu interconnect bonding method. Compared to traditional solder-based connections, the new method demonstrated ultra-high density of 6 um-pitch and good stability at 300 oC, paving way to realise future 3-D integrated circuits (ICs) and systems.
Reference:
1.    Lan Peng et. al., “Ultra-fine Pitch (6um) of Recessed and Bonded Cu-Cu Interconnects by 3D Wafer Stacking”, IEEE Electron Device Letters, Vol. 33, Iss. 12, Pg. 1747 - 1749, 2012