High permittivity neodymium-doped barium titanate sintered in pure nitrogen

This paper investigated the resistivity and dielectric properties of neodymium-doped BaTiO3. The influence of variable doping concentration and Ba/Ti ratio on densification, microstructure, resistivity and dielectric properties was studied profoundly. A new dielectric with high permittivity of 3,00,000 and low dissipation factor of 0.05 measured at 1 kHz, meeting the EIA X8R temperature characteristic was obtained in this study. Resistivity of the material was 10(9) Omega cm orders of magnitude. The starting material was hydrothermally synthesized BaTiO3, the sintering atmosphere was pure nitrogen. When Ba/Ti ratio was identical, with neodymium concentration increasing, the apparent density decreased, sintering shrinkage of ceramic becomes smaller and ceramic is less dense, resistivity decreased, dielectric constant decreased and dielectric loss increased. Whereas when doping concentration was fixed, with Ba/Ti ratio increasing, the grain size of ceramic becomes smaller and ceramic was denser, resistivity decreased, dielectric constant increased and dissipation factor decreased. (C) 2004 Elsevier Ltd and Techna Group S.r.l. All rights reserved.