Characterization of nitrogen in a-CNx thin films by gas effusion spectroscopy

Abstract The evolution and characterization of nitrogen N 2 in amorphous CN x (a-CN x ) have been studied by using gas effusion spectroscopy. In gas effusion spectra for a-CN x thin films, N 2 evolution peaks are found near 200, 400, 600 and 700°C. The N 2 peak near 200°C disappears after hydrogen plasma treatment. In the gas effusion spectrum of H 2 for a sample treated by hydrogen plasma, a very small shoulder would be found near the temperature of the H 2 evolution peak in chemical vapor deposited diamond. By ultra-violet irradiation, the amplitudes of the N 2 evolution peaks above 400°C increase and the x =N/C ratio obtained by X-ray photo-electron spectroscopy increases from 0.5 to 0.7. From these results and comparison with other works, the origin of the N 2 evolution peaks near 200 and 400°C could be estimated as N 2 related to a graphite-like structure and N 2 from CN, respectively, and either N 2 evolution near 600°C or near 700°C, or both, could be related to CN bonds.