Improvement of Dielectric Properties of SrTiO3-Based materials Though Grain-Boundary Engineering

Abstract

When an oxide melt is infiltrated into sintered SrTiO3, the liquid films formed between SrTiO 3 grains are often observed to migrate. This paper shows two techniques for controlling the liquid film migration during the melt infiltration. An oxidation treatment of Nb2Os-doped SrTiO3 between a sintering in 95N2-5H 2 and a melt infiltration in air suppressed the migration as did a proper ratio (-1) of Bat and Cat in an infiltrant. The observed migration suppression was attributed to the formation of a thin oxidized layer whose lattice parameter was similar to that of bulk SrTiO 3 grain. The migration suppression resulted in a considerable increase in dielectric properties.