Effect of Heat Treatment on Microstructure of BaTiO3 Solidified by Aerodynamic Levitator

초록

Barium titanate (BaTiO3) is one of the most important ferroelectric ceramics due to its outstanding dielectric and ferroelectric properties in applications for multilayer capacitors, thermistors, thermal sensors and electric devices. In this study, BaTiO3 was solidified using an aerodynamic levitator, and the effect of heat treatment on microstructure of BaTiO3 was investigated. The domain walls with width of ~400 nm were observed in BaTiO3 grains. The composition shift from stoichiometric BaTiO3 to Ti- or TiO2-rich composition was incurred due to evaporation of BaO. Ti-rich Ba6Ti17O40 was formed by the reaction with excess TiO2 and BaTiO3 during heat treatment at 1000oC. A diffuse-interface was observed, indicating that the Ba6Ti17O40 was formed by atomic diffusion.