Thermodynamic properties and phase equilibria in the silicon-phosphorous system

Knudsen effusion mass spectrometry and a static method were used to study t he vapor composition and the thermodynamic properties of the Si-P melt with the phosphorous content from 0.09 to 26.5 at.% in the temperature range 15 07 to 1831 K. A representative file of experimental data comprising about 1 00 values of phosphorus activity at various concentrations and/or temperatu res was obtained. The thermodynamic characteristics as functions of tempera ture and concentration were approximated by the ideal associated-solution m odel under the assumption that SiP and Si2P complexes exist in the melt. Th e boundaries of the region of liquid phase stability on the phase diagram w ere computed, and agreement with the available experimental information was obtained.