Abstract:

The nonstoichiometric β-SiC powders were synthesized via combustion reaction of Si and C system in a 0.1 MPa nitrogen atmosphere, using Teflon as the chemical activator. The prepared powders were invistigated by XRD and Raman spectra. The results indicates that the cell parameters of all the prepared β-SiC powder
are smaller than the standard value of β-SiC because of generation of CSi defects. The complex permittivity of prepared products was carried out in the frequency range of 8.2−12.4 GHz. It shows that the dielectric property of prepared β-SiC powder decrease with increasing PTFE content. The effect of CSi defects on dielectric property of -SiC powder has been discussed.

Key words: Silicon carbide, Carbon antisite, Dielectric property