A method is provided for forming high dielectric constant (high-k) films for semiconductor devices. According to one embodiment, a metal-carbon-oxygen high-k film is deposited by alternately and sequentially exposing a substrate to a metal-carbon precursor and near saturation exposure level of an oxidation source containing ozone. The method is capable of forming a metal-carbon-oxygen high-k film with good thickness uniformity while impeding growth of an interface layer between the metal-carbon-oxygen high-k film and the substrate. According to one embodiment, the metal-carbon-oxygen high-k film may be treated with an oxidation process to remove carbon from the film.