Novel luminescence properties of a-C:H films produced by using an organic source at various substrate temperatures

Abstract Hydrogenated amorphous carbon films have been fabricated using an organic carbon source (xylene), at substrate temperatures 10–300°C in plasma-enhanced chemical vapor deposition (PECVD) system. We found that, the carbon films contain π-bonded clusters with aromatic units, whose size decreased with increasing substrate temperature. For samples deposited at lower substrate temperature, several photoluminescence (PL) bands were observed, which we attributed to the recombination through some luminescent centers associated with π-bonded structures. For samples deposited at higher substrate temperature, only a single peak with a width greater than the widths of the PL peaks observed in the lower temperature films, which is similar with that of methane-based a-C:H films.