In situ preparation of calcium carbonate films

The in situ preparation of calcium carbonate films in an ultra high vacuum (UHV) is inhibited by the decomposition of CO2 molecules at the surface and the absence of CO2 bulk diffusion. Therefore, it is not possible to prepare such films simply by CO2 exposure to a calcium layer.We investigated different approaches for the preparation of CaCO3 films in an UHV. Among these, only the simultaneous evaporation of Ca atoms in a mixed O2 and CO2 atmosphere is able to produce well defined stoichiometric calcium carbonate films. Metastable Induced Electron Spectroscopy, Ultraviolet Photoelectron Spectroscopy and X-ray Photoelectron Spectroscopy are employed to verify quality and purity of the films.