DEVELOPMENT AND EVALUATION OF DIE MATERIALS FOR USE IN THE GROWTH OF SILICON RIBBONS BY THE INVERTED RIBBON GROWTH PROCESS-TASK ll-LSSA PROJECTnQuarterly Report No. 3, April 1-June 30, 1978

摘要

The thermal stability of CVD SiO3N4 layers in contact with molten silicon has been studied by x-ray analysis. The results indicate that these layers are converted to the a and β phases of Si3N4 with the β phase pre¬dominating. The β phase content increases with time, as also observed in our tests on CVD Si3N4 layers. However, in the latter case the a phase was the dominant phase. Our results to date indicate that the g phase is the more stable form in contact with molten silicon. This explains why CVD oxynitride layers appeared to be more stable in contact with molten silicon than CVD Si3N4 layers in our previous experiments. The oxygen present in the oxynitride layers is apparently removed during contact with the silicon melt with simultaneous conversion to Si3N4, principally the 8 form.