Optical emission spectroscopy on Ar/N/sub 2/ and Ar/N/sub 2//C/sub 2/H/sub 2/ expanding thermal plasmas

This work has been carried out in connection with the possibilities to deposit carbon nitride materials by expansion thermal plasma assisted chemical vapour deposition (ETP-A-CVD). With the same technique high deposition rates and good quality a-Si:H and a-C:H materials have been obtained. A study of the intensity of atomic lines and molecular bands in a Ar/N/sub 2/ and Ar/N/sub 2//C/sub 2/H/sub 2/ expanding thermal plasma has been performed. In the case of the Ar/N/sub 2//C/sub 2/H/sub 2/ mixture rotational and vibrational temperatures were obtained by comparing computer simulated spectra of the CN(B/sup 2/ Sigma -X/sup 2/ Sigma , Delta v=0) spectral system bands with the experimental spectra. The CN ground state density is determined by taking into account the self-absorption of the CN band