Surface characterization of microwave-assisted chemically vapour deposited carbon deposits on silicon and transition metal substrates☆

Carbon films deposited on silicon and transition metal (iron, cobalt, nickel) substrates were prepared by a microwave-assisted chemical vapour deposition process. X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES) in the scanned mode and Raman spectroscopy were used to characterize these deposits. From the analysis of the C KVV fine structure we can conclude that the carbon film is diamond like or diamond on silicon and graphite-like on cobalt and nickel. On iron two forms, graphitic and probably amorphous, coexist. In addition, scanning Auger microscopy (SAM) provides chemical images of the deposits, which allows the areas covered or uncovered by the carbon film to be displayed. XPS, AES and SAM in combination with Raman spectroscopy are thus efficient and complementary tools to determine both (i) the nature of the carbon deposits and (ii) the adhesion relationship between the substrate and the films, which are two main challenges in the preparation of hard protective coatings.