Damascene Benchmark of Ru, Co and Cu in Scaled Dimensions

The alternative metals Ru and Co are benchmarked to Cu in a damascene vehicle at scaled dimensions. The Ru and Co nanowires have a higher resistivity but show, when barrierless, a lower increase of the line resistance versus trench cross-sectional area compared to Cu. Therefore, both Ru and Co are superior to Cu in resistance for trenches smaller than 250nm ² . The electrical benchmark is complemented with via resistance predictions using calibrated models. This modelling indicates a significant reductions of the via resistance for barrierless Co and Ru. The electro migration (EM) performance reveals that the barrierless Ru systems are robust with higher lifetimes compared to Cu and Co.