Effect of Particle Size on Target Sintering Behavior of Cubic ITO Nanopowders

The effect of particle size on the density and resistivity of ITO green bodies and targets was systematically investigated. The experimental results show that the relative density of ITO green bodies decreases with the increase of ITO particle size. When the particle size is 10.7 nm, the relative density of ITO green bodies rises to the maximum value of 56.6%. The resistivity declines exponentially with the increase of particle size, which satisfies the exponential equation of R = exp(−41.823 × d). When the particle size is 41.6 nm, the resistivity reaches the minimum value of 0.8 Ω·cm. The relative density of ITO target decreases with the increase of particle size. Fine particles can increase the driving force of densification in initial stage. Electron mobility, caused by grain boundary scattering, will increase due to the increase of particle size or the decrease of grain boundary potential. When the particle size is 10.7 nm, the target with compact grain stacking and low porosity shows a maximum relative density of 99.25%, and the resistivity reaches the minimum value of 0.34×10−3 Ω·cm.