Conduction and dielectric behaviour of SiC nano-sized materials

SiC nanopowders have been investigated by means of dielectric relaxation sp ectroscopy over the frequency range 0.1 Hz-1 GHz and sample temperature ran ge 150-570 K. The relaxation processes and the electrical conductivity are analysed using the Havriliak-Negami dielectric response. The electrical and dielectric properties are interpreted taking into account the material com position, grain morphology and the nature of the interfaces. We have shown that the dielectric and electrical behaviour are influenced by interfacial polarisation in powders with high specific surfaces. (C) 2000 Elsevier Scie nce Ltd. All rights reserved.