We prepared ruthenium thin films by chemical vapor deposition using a liquid bis(ethylcyclopentadienyl)ruthenium [Ru(EtCp)(2)] precursor in an oxidizing atmosphere, and then investigated the electrical resistivity. thermal stability, and conformality of these films. As a result of amorphous RuO, partly forming in the ruthenium film. the electrical resistivity increased with increasing growth temperature and O-2/(Ar + O-2) ratio, However, the partial oxides did not affect the intrinsic transport mechanism of electrical conduction. In addition, no change in the morphology of the ruthenium film was observed after heat-treatment at 700 degreesC. even when the partial oxides remained in the as-deposited ruthenium films. Precise control of the growth conditions enabled fabrication of conformal ruthenium electrodes. For example, using a low O-2/(Ar O-2) ratio of 1.3% and a low growth temperature of 230 degreesC or less resulted in excellent step coverage of almost 100.