| Titanium was deposited onto 430 stainless steel substrate by means of chemical vapor deposition (CVD) from TiCl₄and H₂gas mixture. Effects of temperature and flow rate of reactant gas on the deposition were investigated. Amount of Ti-deposition was increased linearly with respect to the time at constant temperature and TiCl₄, partial pressure. When the total flow rate was below 500ml/min, the deposition rate of Ti was increased linearly with the square root of the total flow rate, whereas above 500㎖/min, the deposition rate of Ti remained constant. Results revealed that below 500㎖/min the deposition rate was controlled by diffusion process while above 500㎖/min, controlled by the surface reaction. It is also postulated that below 1100℃ the deposition reaction is controlled by the surface reaction (activation energy of 36.3㎉/mole), and above 1100℃ the process is controlled by the adsorption of the reactant species TiCl₂(activation energy of 12.7㎉/mole). |
|
