In this paper, we present a comparative study of microstructure, crystallinity, and physical properties of MOCVD-grown Er2O3 and Gd2O3 films, which are grown under identical conditions and using analogous precursors. They are characterized by the variety of techniques for their structure and properties. As-grown films were polycrystalline. Incorporation of heteroatomic species into the film's matrix, such as carbon, was dependent onto the oxides types and film's growth conditions. Er2O3 film displays 5.8 eV and Gd2O3 film exhibit 5.4 eV bandgap. Electrical characterizations show that the as-grown films were leaky. Thin films of Er2O3 display similar properties as observed in their thick counterparts, which manifest that it is possible to scale down these films for potential uses. (c) 2007 Elsevier B.V. All rights reserved.