Thermochemistry of silicon carbide growth by chemical transport reactions
Résumé
Chemical Vapour Transport is a well known process widely used for the growth of monocrystals. This paper is a thermodynamic overview of different heterogeneous chemical systems, promising for the growth of silicon carbide by means of chemical transport reactions. The systems are Si-C-Y where Y is oxygen or a chalcogen (S, Se) and Si-C-H-X where X is an halogen (Cl, Br, I). We studied in a first step the gas phase composition obtained from SiC etching with the transporting agent as a function of temperature. In a second step, we report the conditions for the formation of silicon carbide from such a vapour at a different temperature. Finally we discuss optimal conditions of temperatures and thermal gradients required for SiC transport with each systems.