Synthesis of amorphous carbon nitride films using dissociative excitation reaction

In this investigation, we aim to produce highly nitrogen-doped carbon, so-c alled carbon nitride, films without the incorporation of hydrogen. In the p hysical vapor deposition process, irradiation by energetic nitrogen ions in creases nitrogen content without the incorporation of hydrogen. In the chem ical vapor deposition process, hydrogen should be included into the film du e to the use of a hydrocarbon reactant. In this study, the synthesis of car bon nitride films having high nitrogen and low hydrogen contents was attemp ted using a chemical-vapor-deposition apparatus. First of all, a CH3CN + Ar mixture was selected as a reactant including hydrogen. Dehydrogenation of the reactant was carried out by plasma decomposition. Second, as a reaction system without hydrogen, BrCN + Ar was also selected fbr starting material s. The dissociative excitation reaction of cyanides with argon metastable a toms produces CN radicals, Ar(P-3(0.2)) + BrCN --> Ar + Br + CN(A(2)Pi(i), B(2)Sigma(+), (4)Sigma(+), (4)Pi). This finally proceeds to the deposition of CN radicals to form the carbon nitride film on a solid-state surface. Wh en using the former reactant, large amounts of hydrogen remained in the amo rphous carbon nitride films, although the amount of hydrogen varied with de position conditions. The sample formed using the latter reactant was amorph ous carbon nitride with very little hydrogen. The nitrogen fraction [N]/([N ] + [C]) of the sample using the latter rectant is as high as similar to 0. 3, higher than those obtained from the samples synthesized with the former reactant.