Deposition mechanism for chemical vapor deposition of zirconium carbide coatings

Zirconium carbide (ZrC) coatings were fabricated by chemical vapor deposition (CVD) using ZrCl₄, CH₄/C₃H ₆, and H₂ as precursors. Both thermodynamic calculation results and the film compositions at different temperatures indicated that zirconium and carbon deposited separately during the CVD process. The ZrC deposition rates were measured for CH₄ or C₃H₆ as carbon sources at different temperatures based on coating thickness. The activation energies for ZrC deposition demonstrated that the CVD ZrC process is controlled by the carbon deposition. This is also proven by the morphologies of ZrC coatings.