Influences of silica additive on sintering and Hall effect of novel transparent In2O3 semiconductive ceramics

Polycrystalline transparent In₂O₃ semiconductive ceramics are successfully fabricated by oxygen atmosphere sintering for the first time. The starting rounded In₂O₃ particles are obtained via pyrolyzing the nanoplate-like hydrated basic sulfate precursor prepared by a chemical precipitation route using hexamethylenetetramine as the precipitant. The silica additive dissolves into the In₂O₃ lattice to form an interstitial solid solution, which promotes the diffusion rate during high-temperature densification process and thus helps to achieve good optical quality for In₂O₃ ceramics. The created interstitial oxygen further compensates the oxygen vacancy in the ceramic body to result in a higher resistivity and lower carrier concentration / carrier mobility. The optical qualities of In₂O₃ ceramics are also found to have slight effects on the resistivity, carrier mobility, carrier concentration, and Hall coefficient.