放電プラズマ焼結によるn型SiCの作製と熱電特性

抄録

Preparation and thermoelectric properties of n-type SiC were studied. Nitrogen doping was performed by mixing 3-10 mass%Si₃N₄. The pellets were prepared by spark plasma sintering (SPS) at 2000°C. The crystal structure of every sintered material is cubic β-type and relative density was higher than 80%. All sintered materials showed n-type conduction and the carrier concentration increased with increasing Si₃N₄ concentration. Seebeck coefficient decreased and electrical conductivity increased with increasing Si₃N₄ concentration. Power factor was improved by the Si₃N₄ doping and the maximum power factor of 1.5×10⁻⁴ W/mK² was obtained for SiC-7 mass%Si₃N₄ at 700°C.