Thermally Stable TiVCrZrHf Nitride Films as Diffusion Barriers in Copper Metallization

In the present study, 10 nm-thick TiVCrZrHf nitride films were developed as diffusion barrier materials for Cu interconnects. The TiVCrZrHf nitride films were prepared at room temperature via reactive magnetron sputtering using a TiVCrZrHf target. Barrier properties were examined by annealing in vacuum at elevated temperatures for 60 min. The results show that the (TiVCrZrHf)N 0.4 and (TiVCrZrHf)N films prevent the reaction between Cu and Si before failure at 600 and 800°C, respectively. The excellent thermal and structural stabilities of nitride for preventing silicide formation are assumed to originate from the incorporation of different-sized elements.