Influence of ions energy on the bonding structure of amorphous carbon nitride films

Amorphous carbon nitride films were prepared at various substrate bias voltage Vb using magnetic filtered plasma stream. The plasma stream was formed by sputtering a high-purity graphite target in nitrogen atmosphere. The incident ions energy was varied by applying different negative bias voltage on the substrate platform. The atomic bond structure and chemical states of C and N atoms in the films as a function of bias voltage were studied by Raman spectra, FTIR spectra and atomic force microscopy (AFM). The results show that amorphous carbon nitride films with larger sp3 CN bond and sp2 CN bond can be formed in a Vb range from −60 to −120 V. The effect of incident ions energy on atomic bond structure and surface roughness of carbon nitride films was discussed.