Influence of plating parameters on reliability of copper metallization

This work investigates the impact of plating parameters on the physical and electrical properties of plated copper films. Process parameters such as the plating current density and wafer rotation speed are known to affect the grain size and the residual stress in plated Cu films. We correlate the process parameters with trapped contamination in the films, which in turn influences the pre/post-anneal grain size and the relaxation of the residual stress. Preliminary reliability measurements show that the longevity of the interconnect structure is dependent on the intrinsic properties of the plated copper.