Effect of sintering temperature and time on composition, densification and electrical properties of InGaZnO4 ceramics

This paper studied the influence of sintering temperature on composition, density and electrical properties of InGaZnO4 ceramics synthesized by conventional solid-state reaction technique. Firstly, IGZO powders were prepared by mechanical ball milling of micron-scale In2O3, Ga2O3 and ZnO mixed powder and the effects of milling time, ball to powder weight ratio (BPR) and dispersant on the properties of mixed powders were investigated by XRD, SEM and laser diffraction particle size analyzer. Secondly, the green compacts formed by mixed powders were sintered at different temperatures (1100, 1200, 1300, 1400 degrees C) and time (0, 1, 3, 6 h), then the sintering behavior and electrical properties of the compacts were analyzed. The results showed that when the BPR was 10:1 and 2 wt % polyammonium acrylate was used as dispersant, the powder owed the best compression performance and the relative density of the green compact reached 67.14%. Owing to the decomposition of In2O3, obvious loss of mass phenomenon occurred during sintering process. When the compact was hold at 1400 degrees C for 150 min, the density of compact reached as high as 99.5%. The lowest resistivity of the compact reached 6.07 x 10(-3) Omega cm when the compact was kept at 1400 degrees C for 3 h.