The partial pressures of the gaseous species in equilibrium with solid silicon in the Si‐H‐Cl system are presented as a function of temperature for different Cl/H ratios and total pressures. Computations were performed using our recently determined value of . Experimental data concerning the deposition and dissolution of silicon over a temperature range of 1200°–1700°K are compared to the equilibrium data and general conclusions drawn about the probable reaction mechanisms involved, especially for decomposition of the compounds and . Particular emphasis is put on attempting to integrate the diverse body of experimental data that exists for silicon deposition from and mixtures at high temperatures.