Investigations on TiN, TiC and Ti(CN) obtained by chemical vapor deposition

The paper presents the results of the chemical vapour deposition (CVD) oF T iN, TIC and TI(CN) using TiCl4, H-2, N-2 and CH4 as educts. The influence o f the deposition conditions like temperature, total pressure and compositio n of the reaction gases on the deposition process is studied and a model fo r the deposition rate is proposed. The deposition process of TiN, TiC and T i(CN) up to a TiCl4 partial pressure of 3.8 kPa can well be described by a power law of first order. Reducing the total pressure results in an increas ed deposition rate, higher apparent activation energy, lower depletion of t he reaction gas and more uniform coatings. The composition of TiN and TiC f ilms is not stoichiometric with respect to N and C (TiN0.6, TiC0.7) and ind ependent of the deposition conditions. The composition of TI(CN) can be cha nged by varying the reaction temperature, which allows to deposit graded la yers. Ceramics coated with TIN and TI(CN) achieve the lowest value of elect rical resistivity (34 mu ohm.cm) at a layer thickness of 11 mu m For TIC a 25 mu m layer is needed in order to achieve a minimum value of 209 mu ohm.c m.