Crystallization of Amorphous SiCN Ceramic Annealed in Vacuum

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 o 1900 n vacuum. Decomposition-crystallization mechanism was used to characterize its crystallization process. Amorphous SiCN begin to decompose below 1300 n vacuum and Si-C-enriched districts are formed and then changes to form |-SiC crystal. Crystallinity degree increases as treated temperature rises. Phase transition from |-SiC to | 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.