Morphologies and growth mechanisms of zirconium carbide films by chemical vapor deposition

Zirconium carbide films were grown on graphite slices by chemical vapor deposition using methane, zirconium tetrachloride, and hydrogen as precursors. The growth rate of zirconium carbide films as a function of temperature was investigated. The morphologies of these films at different temperatures were also observed by scanning electron microscopy. The results indicated that the deposition of zirconium carbide was dominated by gas nucleation at temperatures below 1523 K, and by surface process at temperatures higher than 1523 K. By comparison of the deposition activation energies for zirconium carbide and deposited carbon, it was determined that the carbon deposition was the controlled process during the growing of zirconium carbide films. The effect of temperatures on the morphologies of zirconium carbide films was also discussed, based on the carbon deposition process.