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

Abstract

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.

Calculation and synthesis of ZrC by CVD from ZrCl4–C3H6–H2–Ar system with high H2 percentage

“…3 and 4 as presented in Ref. [16]) using CH 4 as carbon source indicated that the morphologies of ZrC from ZrCl 4 -CH 4 -H 2 -Ar system also changed greatly with temperature. However, a smooth and dense ZrC coating can be deposited only at 1673 K from the ZrCl 4 -CH 4 -H 2 -Ar system, where the temperature is higher than 1523 K here.…”

“…According to previous experimental and theoretical results on the deposition of ZrC [15,16] and SiC [21,22], the ratio of reactant gases is critical in the synthesis process. To facilitate the calculation, the relationship between ˛, ˇ and the production of condensedphases (ZrC and C) was firstly illustrated.…”

“…A study conducted by Liu et al [16] on the influence of temperature about the deposition of ZrC (Figs. 3 and 4 as presented in Ref.…”

“…Several studies reported the CVD of zirconium carbide and carbon-zirconium carbide alloys [10][11][12][13][14][15][16][17][18]. The ZrC coatings are generally synthesized by zirconium halide [11,12] and hydrocarbons, such as CH 4 and C 3 H 6 [14,15].…”

“…The effects of synthesis parameters such as deposition temperature [16,17], H 2 flux [18] on the final products have been systematically studied. In general, ZrC with stoichiometry can be deposited at relative low temperatures by using C 3 H 6 rather than CH 4 because C 3 H 6 is easier to decompose than CH 4 [19].…”