Influence of nitrogen ion energy on the Raman spectroscopy of carbon nitride films

Carbon nitride films were deposited by filtered cathode vacuum arc combined with radio frequency nitrogen ion beam source. Both visible Raman spectroscopy and UV Raman spectroscopy are used to study the bonding type and the change of bonding structure in carbon nitride films with nitrogen ion energy. Both C-N bonds and C dropN bonds can be directly observed from the deconvolution results of visible and UV Raman spectra for carbon nitride films. Visible Raman spectroscopy is more sensitive to the disorder and clustering of sp(2) carbon. The UV (244 nm) Raman spectra clearly reveal the presence of the sp(3) C atoms in carbon nitride films. Nitrogen ion energy is an important factor that affects the structure of carbon nitride films. At low nitrogen ion energy (below 400 eV), the increase of nitrogen ion energy leads to the drastic increase of sp(2)/sp(3) ratio, sp(2) cluster size and C-N bonds fraction. At higher nitrogen ion energy, increase leads to the slight increase of C dropN bonds fraction and sp(2) cluster size, slight decrease of C-N bonds fraction and sp(2)/sp(3) ratio. (C) 2001 Elsevier Science B.V. All rights reserved.