Effects of acetylene/ammonia mixtures on the properties of carbon films prepared by thermal chemical vapor deposition

►Carbon films can be fabricated using C2H2 and NH3 by TCVD at 1113 K and 8 kPa. ► The carbon films of this study are graphite-like. ► The ordering degree of carbon films increases with increase of the NH3/C2H2 ratio. ► The number of sp2 carbon sites in films increases with increase of the NH3/C2H2 ratio. ► NH3 molecules show the suppressive effect at the temperature exceeding 1073 K.