Near-edge x-ray absorption fine structure and Raman characterization of amorphous and nanostructured carbon films

Amorphous and nanostructured carbon films were grown by using two different techniques: ion sputtering and cluster beam deposition. The films were studied by near-edge x-ray absorption fine structure~NEXAFS!and Raman spectroscopy. Depending on the precursors, atoms, or clusters, the films are characterized by a different sp2/sp3 ratio which influences the mechanical and the electronic properties. Due to the sensitivities of NEXAFS~local order!and Raman~medium-range order!, we have characterized and compared the structure of the films over different length scales. The complementarity of NEXAFS and Raman techniques for the characterization of disordered forms of carbon is here presented and discussed. We also present an original method of NEXAFS spectra calibration allowing a better determination of peak positions.