Analysis of the structure of multi‐component carbon films by resonant Raman scattering

Diamond and carbonaceous films grown in a microwave assisted plasma reactor have been characterized by x‐ray diffraction, scanning electron microscopy, and Raman spectroscopy. This study is mainly focused on the identification of the different carbonaceous compounds which can coexist with the diamond depending on the synthesis parameters. Selective etching reactions and the excitation wavelength dependence of Raman cross sections of the different carbon species reveal that the broad and poorly structured Raman spectra in the 1100–1700 cm−1 region contain six components that arise from three different carbonaceous species: (i) one species is graphitic and is identified from the components at about 1350 and 1590 cm−1 which are resonantly enhanced as compared to the other components when the excitation energy is lowered from 3 to 2 eV. (ii) The second species is associated with the two broad bands at 1350 and 1550 cm−1 and is attributed to amorphous diamond‐like carbon (a‐C:H); both bands are resonantly enha...