以六甲基二硅氮烷为单一前驱体，采用电热裂解化学气相沉积技术制备了SiCN陶瓷. 借助X射线衍射仪、透射电子显微镜研究了真空环境中非晶SiCN陶瓷在1300～1900℃范围内的晶化行为，并根据研究结果，运用分解-结晶机理解释了其晶化过程. 非晶SiCN陶瓷在低于1300℃开始发生分解，形成富Si-C区域，并最终发生β-SiC结晶. 其结晶度随热处理温度的升高而愈加明显.在1700℃处理时发生β-SiC→α-SiC相变. 分解形成的N-难以与Si-结合形成富Si-N区域，最终以N2形式溢出，在整个热处理温度范围没有出现氮气下热处理时存在的Si3N4结晶.
SiCN ceramic was fabricated by electro-thermal pyrolysis using hexamethyldisilazane as precursor. X-ray diffraction and transmission electron microscope were employed to study crystallization process of amorphous SiCN after annealing at temperature from 1700℃ to 1900℃ in vacuum. Decomposition-crystallization mechanism was used to characterize its crystallization process. Amorphous SiCN begin to decompose below 1300℃ in vacuum and Si-C-enriched districts are formed and then changes to form β-SiC crystal. Crystallinity degree increases as treated temperature rises. Phase transition from β-SiC to α-SiC occurs after annealing at 1700℃. The nitrogen is released in the form of N2 and Si3N4 crystal is not detected though it often exists in the SiCN annealed in N2 atmosphere.
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