Stability of carbon nitride films prepared from volatile CN species via atomic transport reactions

Thin CNx films were deposited by inductively coupled plasma chemical vapour deposition (ICP-CVD) at different substrate temperatures. Instead of the conventional gaseous carbon precursors, a pure carbon mesh was used as carbon source with nitrogen as a carrier/reaction gas. The CNx films are formed from volatile CN species produced via atomic transport reactions. The deposition rate decreases from 3.2 nm/min at room temperature to almost zero at 150 degrees C. The nitrogen fraction N(N + C) is at about 0.5, as revealed by various analytical techniques; the composition remains unchanged when varying the substrate temperature. The films are composed mainly of sp(2) carbon atoms bonded to nitrogen atoms. The CNx layers are stable upon annealing at temperatures up to 300 degrees C; the surface contamination is removed, while no changes in the nitrogen atomic fraction and in the bonding structure are observed. (C) 2000 Elsevier Science S.A. All rights reserved.