Thermodynamical Analyses and Experiments for the Preparation of Silicon Nitride

The vapor growth of silicon nitride film is studied thermodynamically for SiH4-NH3-H2 and SiCl4-NH3-H2 systems. By calculating the partial pressures of gaseous species involved in the reactions, the deposition rates of silicon nitride are determined. The theoretical results for SiH4-NH3-H2 system are compared with the experimental data obtained by Bean et al. and the agreements are found quite good, indicating that an equilibrium or at least a quasi-equilibrium is always established. However for SiCl4-NH3-H2 system the agreements are rather poor, suggesting the deviation from the quasi-equilibrium states or the existence of the complex chemical intermediates etc.