Les différentes voies de modélisation macroscopique du procédé de dépôt de SiC par voie gazeuse

Abstract

The different macroscopic modelling routes and chemical databases are reviewed for the growth of silicon carbide from the vapour phase in the Si-C-H-Ar system. Theses databases have been built up by experts over many years through the critical assessment of primary experimental data and ab-initio calculations. The thermodynamic modelling route addresses several important issues with respect to vapour deposition techniques. This approach is a useful tool in understanding the complex chemistry involved during the growth, but should be used with careful attention to the assumptions underlying the application. The transport modelling approach extends the previous analysis to dynamical systems. It is based on the conservation equations for momentum and heat transfer combined with mass transfer including thermodiffusion and chemical reactions based on thermodynamic and kinetic data. In addition to empirical, lumped chemical kinetic models, we propose a new modelling route linking transfers models with local thermochemical equilibrium (LTCE) computations. The modelling results have been validated with the help of the SiC sublimation technique for the transfer-LTCE concept, and of the chemical vapour deposition technique for lumped chemistry models. The simulated results allow the quantification of the different modelling proposals.