DEVELOPMENT AND EVALUATION OF DIE MATERIALS FOR USE IN THE GROWTH OF SILICON RIBBONS BY THE INVERTED RIBBON GROWTH PROCESS-TASK ll-LSSA PROJECT

摘要

The results of emission spectroscopic analysis indicate that molten silicon (sessile drop) can remain in contact with hot-pressed Si3N4 (99.2% theoretical density) for prolonged periods without attaining the impurity content level of the nitride. It is interesting to note that, although MgO was used as binder (~3.8%), Mg was not found present in the silicon sessile drop in quantities much above the level initially present in the silicon source material.nThe conversion of CVD silicon oxynitride to β-Si3N4 can be carried out at high temperature in N2 (~1600°C), by contact with molten silicon or by a combination of these steps. Conversion in the presence of molten silicon appears preferable.