  Ru has been considered a candidate to replace Cu-based interconnects in VLSI
circuits. Here, a methodology is proposed to predict the resistivity of (Ru)
interconnects. First, the dependence of the Ru thin film resistivity on the
film thickness is modeled by the semiclassical Mayadas-Shatzkes (MS) approach.
The fitting parameters thus obtained are then used as input in a modified MS
model for nanowires to calculate wire resistivities. Predicted experimental
resistivities agreed within about 10%. The results further indicate that grain
boundary scattering was the dominant scattering mechanism in scaled Ru
interconnects.
