利用硅片线锯屑合成氮氧化硅粉体研究

Study on Synthesis of Silicon Oxynitride Powders from Wire Saw Dusts of Silicon

以回收提纯硅片线锯屑粉与气相白炭黑为原料,合成出晶须状氮氧化硅粉体。实验研究了原料摩尔配比、保温温度、保温时间等工艺参数对氮氧化合成产物的影响。结果表明,回收提纯硅片线锯屑粉与气相白炭黑摩尔比为2.0∶1~2.6∶1、保温温度为1380℃、保温时间为4 h条件下可获得较为纯净的氮氧化硅粉体。产物中同时伴生一种类似于O1-Si Al ON结构的氮氧化硅低温亚稳相（LM Si2N2O）,且该亚稳相含量随着原料摩尔配比的降低、温度的升高、时间的延长逐渐降低。所形成的氮氧化硅呈晶须状的原因与白炭黑的气化挥发及随后的氮氧化硅气相沉积生长机制有关。

Silicon oxynitride whisker-like powders were synthesized from recovered wire saw dusts and fumed white carbon black. The effects of molar ratio, temperature and time on oxynitridation were investigated in detail. The results show that the pure silicon oxynitride powders can be obtained at 1380 ℃, 4 h and molar ratio 2.0： 1-2.6： 1. Low-temperature metastable phase （LM Si2N20） was discovered and inferred in the oxynitridation, which exhibiting a similar crystal structure to O1-SiAION. With the molar ratio increased, the temperature improved and the time prolonged, the LM Si2N20 content increased in the oxynitridation. Silicon oxynitrde fibers were grown by vapor deposition mechanism owing to vaporization of fumed white carbon black, leading to formation of the crystal whiskers of oxynitride.