Characterization of the Grain Boundary in Fine-Grain BaTiO₃ Dielectric Ceramics for Multilayer Ceramic Capacitors

抄録

Driven by market, multilayer ceramic capacitors (MLCs) are expected to increase volume efficiency and reduce cost.One of the most important keys to achieve these objectives is to reduce the thickness of the dielectric layers. As reducing the thickness of them,the number of the grains between the electrodes decreases.Therefore, the role of the grain-boundary becomes important, and it is required to control the composition or the chemical states of the grain-boundary. BaTiO₃ dielectric ceramics were prepared, which concentrated additives at the grain-boundary and has no core-shell structure. High-resolution TEM-EDX and the newly developed chemical etching analysis revealed the composition of the grain-boundary. Doping at grain-boundary with additives was efficient for fine-grain BaTiO₃ ceramics to increase reliability of MLCs.