The Influence of BaTiO_3 Tetragonality by Solid State Synthesis on MLCC's Dielectric Characteristics

摘要

BaTiO_3 powders with particle size 0.1 μm were made by solid state synthesis. To make high tetragonality BaTiO_3 powder, mixture of TiO_2 and BaCO_3 was calcined in vacuum condition. And to make low tetragonality BaTiO_3 powder, the mixture was calcined in air condition. With each powder, MLCCs with Ni-internal electrode were fabricated. Relationships between temperature and relative dielectric constant of MLCCs' dielectric layers were analyzed and their dielectric grains were observed by TEM-EDS. As the result, MLCC made from high tetragonality BaTiO_3 powder had good temperature characteristics and core-shell dielectric grains.