CVD of Ti3SiC2

Experiments and thermodynamic calculations were performed to gain a better understanding of the CVD of Ti3SiC2. The computer program SOLGASMIX-PV was used to calculate deposition diagrams for the TiCl4–SiCl4–CCl4–H2 reagent system. The effects of hydrogen to reagent concentration ratio, temperature, and pressure were explored using a “box” type study surrounding a central set of conditions (temperature 1300 K, pressure 760 kPa, and a hydrogen to reagent concentration ratio of 20:1). The calculated results were not in good agreement with the experimental results, which suggests that either kinetics plays an important role in the CVD of Ti3SiC2, or the thermodynamic data are not sufficiently known. The experimental study of the CVD of Ti3SiC2 revealed important morphological details of the Ti3SiC2 deposits. Complicated microstructures, consisting of various combinations of Ti3SiC2, TiC, and TiSi2, were obtained. The preferred orientation of Ti3SiC2 basal planes was shown to be perpendicular to the substrate, with the degree of orientation and other microstructural characteristics dependent on temperature.