STRUCTURAL AND MORPHOLOGICAL PROPERTIES OF NANOMETER CARBON FILMS OBTAINED BY ELECTRON BEAM SPUTTERING OF GRAPHITE

Nanometer-thick carbon films on metal (copper, steel) and silicon substrates are obtained by the electron sputtering of graphite. The substrate temperature was varied from 350 to 600 degrees C with an increment of 50 degrees C, and the sputtering time from 1 to 10 s. The produced carbon films are studied using Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), atomic force microscopy, and electron paramagnetic resonance (EPR) spectroscopy. From the analysis of Raman spectra, it is found that, at the temperatures of metal substrates below 550 degrees C, the carbon films formed on them are amorphous and have a graphite-like structure at higher substrate temperatures. At the same time, the films formed on silicon substrates at temperatures below 600 degrees C are amorphous. The results obtained from the Raman spectra correlate with the XPS data. It is shown that both the temperature and the substrate material (metal or silicon) affect the film morphology. As the substrate temperature increases from 350 to 600 degrees C, the average size of surface irregularities increases for carbon films on both the metal and silicon substrates. The EPR studies show that the available structural film defects, which are responsible for the manifestation of the so-called defect bands (D and D' ones) in the Raman spectra, are not paramagnetic.