Preparation and Characterization of X8R Fine-Grained Dielectric Ceramics

Fine-grained BaTiO 3 -based nonreducible ceramics were obtained by a conventional mixing method and the dielectric and electrical properties were characterized. The average grain size was less than 200 nm. The materials provided a dielectric constant of 1300 and satisfied the Electronic Industries Association (EIA) X8R specification. Fine-grained ceramics showed a better performance under a direct current (DC) field at high temperatures, compared with coarse-grained ceramics. Impedance analysis was conducted to determine the activation energy and to evaluate the ionic transference number. Moreover, capacitance variation under a DC field was also largely improved for fine-grained ceramics and relative mechanisms were examined.