Synthesis of TiC thin films by CVD from toluene and titanium tetrachloride with nickel as catalyst

Abstract

Titanium Carbide TiC x was deposited onto quartz substrates by the chemical vapour deposition (CVD) method. TiC x thin films were obtained from titanium tetrachloride (TiCl 4) and toluene (C 6 H 5 CH 3) as carbon source. Deposits were carried out in the range of substrate temperatures from 300 to 1100 C, with a source gas molar ratio (C 6 H 5 CH 3 /TiCl 4 + C 6 H 5 CH 3) of 0.8. There was two deposit processes; the first was to carry out without nickel as catalyst and the second with nickel as catalyst. Results showed that the effect of nickel as catalyst is very relevant to obtain TiC x. TiC 0.87 thin films, 0.5 m thickness, were obtained for deposition temperatures above 900C using nickel as catalyst. In this case a cubic structure, with a lattice parameter of 4.327 Å and a hardness of 2900 Vickers, was obtained at 1100 0 C. whilst for substrate temperatures between 300 to 900°C with nickel as catalyst amorphous carbon samples were obtained. For the samples prepared without the presence of the nickel as catalyst only C amorphous thin films were obtained for all deposit temperatures.