Published online by Cambridge University Press: 15 February 2011
The properties and structure characteristics of the ultrafine Si-N-C powders synthesized from laser induced hexamethyldisilazane and ammonia gas phase reactions were characterized by multiple techniques. Result shows that the Si-N-C particles are uniform in diameter with narrow size distributions and less agglomerated. The powders exhibited a short distance ordered structure which was distorted at high temperature annealing. HTEM observation shows that the particles are amorphous or have nano-composite structure with SiC particles dispersed in the amorphous Si-N-C matrix. The nucleation and growth of the composite particles occurred by the polymerization of the ligand formed from the decomposition of Si-CH3 and N-H bonds in hexamethyldisilazane accompanied by the release of small hydrocarbon gases.