Influence of deposition conditions on electrical and mechanical properties of Sm 2 O 3 -doped CeO 2 thin films prepared by EB-PVD (+IBAD) methods. Relationship between investigated film and substrate at indentation

The study of polycrystalline CeO 2 + x Sm 2 O 3 ( x = 0, 10.9–15.9 mol %) thin films deposited by Electron Beam Physical Vapour Deposition (EB-PVD) and Ionic Beam Assisted Deposition (IBAD) techniques on the Si substrate was devoted to the influence of deposition conditions used, namely composition x , deposition temperature T dep and Ar + ion bombardment as well as the structure and (micro)structure on the (micro)hardness H using the differential hardness, H dif , as a parameter. The investigations were made using, as in our recent papers, the depth sensing indentation (DSI) technique. The study was focused on the depth dependence of the film/substrate system response on the indentation response from the surface of films up to the film/substrate interface. This study has shown that the critical indentation depth, where the influence of substrate is negligible, can be observed for some CeO 2 films doped with Sm 2 O 3 as well as for undoped CeO 2 films, both deposited at T dep = 200°C without IBAD as well as using IBAD. Besides it, a wavy character of differential curve due to the inhomogeneities of films was observed with good reproducibility at some films. It was proven, that the method of differential hardness measurement is applicable for the determination of critical indentation depth as well as for the study of microstructure response of thin films from the film surface up to the film/substrate interface. Results of this study are described and discussed.