Microstructure and electrical characteristics of MnTa-doped ZnO–V2O5-ceramics with sintering

The microstructure and electrical properties of MnTa-doped ZnO–V2O5-ceramics with sintering was investigated. The microstructure consisted of a primary phase of ZnO grains and minor secondary phases such as Zn3(VO4)2, ZnV2O4, and TaVO5, which act as liquid-phase sintering aids. The sintered density decreased from 5.69 g cm−3 to 5.52 g cm−3 due to the volatility of V2O5 in accordance with increasing sintering temperature. The maximum nonlinear coefficient (28) was obtained at 925 °C. The donor concentration increased from 1.07 × 1018 cm−3 to 3.56 × 1018 cm−3 in accordance with increasing sintering temperature and the barrier height exhibited the maximum value (1.25 eV) at 950 °C.