Evaluation of precursors for chemical vapor deposition of ruthenium

Several commercially available organometallic precursors have been evaluated for metallorganic chemical vapor deposition (MOCVD) of pure ruthenium films. Of these, only a dimer, [RuC 5H 5(CO) 2] 2, proved suitable for CVD. On patterned Si 3N 4 and flat barium strontium titanate (BST), pure, conductive, conformal ruthenium films were grown from this dimer when oxygen was used as a reaction gas. Without oxygen, significant amounts of carbon were incorporated into the film. Oxygen and substrate temperature effects on ruthenium CVD film growth were investigated by resistivity measurements, in situ X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Growth conditions and possible mechanisms are discussed.