Nucleation and Growth of Nanophasic CeO2 Thin Films by Plasma‐Enhanced CVD

Abstract

AbstractNanophasic CeO2‐based thin films were grown at low temperatures on SiO2 and Si(100) by plasma‐enhanced (PE) CVD from a CeIV β‐diketonate first generation precursor. Film depositions were carried out in low‐pressure Ar–O2 plasmas at temperatures between 150 °C and 300 °C. The film microstructure was investigated by glancing incidence X‐ray diffraction (GIXRD) and transmission electron microscopy (TEM), while the surface and in‐depth chemical composition was studied by X‐ray photoelectron spectroscopy (XPS), and secondary ion mass spectrometry (SIMS), respectively. Optical properties were analyzed by UV‐vis optical absorption. Nanostructured CeO2‐based films, with crystal size less than 6 nm and a controllable CeIV/CeIII ratio, were obtained at temperatures even lower than that required for precursor vaporization (170 °C). In particular, TEM analyses showed an island growth mode and different microstructural features as a function of the substrate used.