Atomic layer deposition of Ru films from bis(2,5-dimethylpyrrolyl)ruthenium and oxygen

Abstract Ru thin films were grown on hydrogen terminated Si, SiO 2 , Al 2 O 3 , HfO 2 , and TiO 2 surfaces by atomic layer deposition from bis(2,5-dimethylpyrrolyl)ruthenium precursor and oxygen. The 4–20 nm thick films on these surfaces consisted of nanocrystalline hexagonal metallic ruthenium, regardless of the deposition temperature. At the lowest temperatures examined, 250–255 °C, the growth of the Ru films was favored on silicon, compared to the growth on Al 2 O 3 , TiO 2 and HfO 2 . At higher temperatures the nucleation and growth of Ru became enhanced in particular on HfO 2 , compared to the process on silicon. At 320–325 °C, no growth occurred on Si–H and SiO 2 -covered silicon. Res…