Electrical Conduction in Sintered SiC Containing BN

Abstract

Electrical properties of SiC sintered with 0.34wt%6.89wt% boron nitride and 2.0wt% carbon in the temperature range of 1900°C2100°C for 30min in vacuum were investigated. Specimens containing 1.15wt% boron nitride (0.5t% boron) showed the most remarkable densification independent of the sintering temperature. The electrical conductivity of specimens containing 1.15wt% boron nitride was the lowest, and the value depended strongly on the frequency and measuring temperature. In order to explain the experimental results, a microstructure model, charge distribution model and energy band model were proposed. The electrical conduction mechanism was discussed based on these models.