Ru thin films were prepared by metallorganic chemical vapor deposition using a cyclopentadienyl-propylcyclopentadienylruthenium(II) precursor and O-2. The nucleation and deposition behavior, thermal stability of the film surface, reaction at the Ru/TiN interface, and the stresses of the Ru thin films were investigated. The films consisted of single phase metallic Ru under all deposition conditions and showed an electrical resistivity as low as 12 muOmega cm. The Ru thin films had a negligible oxygen content. Therefore, the interface between Ru and TiN was not changed after annealing at 600degreesC under a N-2 atmosphere. However, the poor nucleation property especially on a SiO2 surface resulted in a rough surface morphology. It was found that the stress of the Ru thin film decreased as the deposition temperature and growth rate increased. The deposition behavior and physical properties of the films were investigated for use as an electrode in a metal-insulator-metal capacitor in future generation dynamic random access memory devices.