The catalytic role of additive components for the nitridation of silicon/additive mixture

抄録

The nitriding behavior of silicon/additives mixture with varied composition was investigated by focusing on the catalytic effect of sintering additives (Y₂O₃ and Al₂O₃) and diluents (Si₃N₄). While sintering additives have originally been mixed to form a liquid phase to promote both densification and grain growth during post-sintering, it was revealed that the addition of Y₂O₃ enhances the nitriding reaction by eliminating the SiO₂ and Si₃N₄ layer on the surface of silicon particles. Further, a synergistic effect resulting in an increased nitridation was verified by concurrent addition of sintering additives and diluents. The contribution of each component of the compact to the promoted nitriding reaction was elucidated in quasi in-situ manner by the combination of phase analysis and thermogravimetric analysis.