Title :
Understanding CMP-induced delamination in ultra low-k/Cu integration
Author :
Leduc, P. ; Savoye, M. ; Maitrejean, S. ; Scevola, D. ; Jousseaume, V. ; Passemard, G.
Author_Institution :
CEA-DRT-LETI, Grenoble, France
Abstract :
In-situ friction characterization during chemical-mechanical polishing (CMP) was investigated to understand delamination mechanisms of a porous ultra low-k (ULK)/Cu stack. By quantifying the delaminated area within the wafer, it was shown that adhesion failure is driven by the work done against the CMP-induced friction force, and is correlated to the adhesion strength of the weakest interface. A low-stress CMP was successfully achieved on a first level of ULK/Cu interconnects having a low adhesion SiC/ULK interface (Gc=1.3 J/m2) and a porous dielectric material with low mechanical properties (Young´s modulus E=3.5 GPa, hardness H=0.7 GPa).
Keywords :
adhesion; chemical mechanical polishing; copper; delamination; dielectric materials; integrated circuit interconnections; integrated circuit metallisation; porous materials; sliding friction; CMP-induced delamination; Cu; SiC; Young´s modulus; adhesion failure; adhesion strength; chemical-mechanical polishing; copper interconnects; friction characterization; friction force; hardness; porous dielectric material; ultra low-k/copper integration; Adhesives; Copper; Delamination; Dielectric materials; Friction; Mechanical factors; Plasma measurements; Silicon carbide; Slurries; Torque measurement;
Conference_Titel :
Interconnect Technology Conference, 2005. Proceedings of the IEEE 2005 International
Print_ISBN :
0-7803-8752-X
DOI :
10.1109/IITC.2005.1499984
