Spark plasma sintering of antimony-doped tin oxide (ATO) nanoceramics with high density and enhanced electrical conductivity

Antimony-doped tin oxide (ATO) nanoceramics used for sputtering targets are successfully prepared by spark plasma sintering (SPS) technology using commercial ATO nanoparticles with particle size of 10–15 nm. The effect of sintering temperature on the microstructure and electrical property of the obtained ATO nanoceramics is investigated. By means of XPS, the Sb5+/Sb3+ ratio of ATO nanoceramics sintered at different temperatures is determined. The results suggest that when the sintering temperature is 1000 °C, ATO nanoceramics show a density of 97.2% and electrical resistivity of 7.9 × 10−2 Ω cm which attribute to an elevated Sb5+/Sb3+ ratio. The main mechanism of conduction is explained through the carrier concentration determined on the antimony content and its oxidation state in the tin oxide lattice.