The interactions of carbon and nitrogen in liquid silicon

Abstract

The interactions between carbon and nitrogen in liquid silicon have been studied experimentally. High purity silicon was melted in silicon nitride crucibles under an Ar atmosphere with a graphite slab inserted in the crucible prior to melting as a carbon source. The system was thus simultaneously equilibrated with Si3N4 and SiC. Samples were extracted in the temperature range 1695-1798 K and analyzed using Leco. It was observed that the simultaneous saturation of nitrogen and carbon caused a significant increase in the solubilities of both elements. The interaction parameters were derived as eNC = 95.01±1-177555±10000/T eNC = 110.83±1.2-207123±12000/T The solubility of carbon in liquid silicon as a function of temperature and nitrogen content was found to follow: CC(T,CN)=(7.37±0.11) exp[-(11731±197)/T-(95.01±1-177555±10000/T)CN·ln(10)] And the solubility of nitrogen in liquid silicon found to follow: CN(T,CC) = 7957.9·exp[-24376/T-(110.83±1.2-207123±12000/T)CC·ln(10)].