Study on Dielectric Properties of BST Based Dielectric Ceramics Doped with CaSnO3

Abstract: CaSnO₃ doped (Ba_0.71Sr_0.29)TiO₃(BST) ceramics were prepared by solid state method. Influence of CaSnO₃ doping amount on the dielectric properties, phase composition and microstructure of BST capacitor ceramics were investigated. The results show that the relativity permittivity(ε_r) of BST ceramics decreases firstly and then increases and decreases, the dielectric loss(tanδ) decreases firstly and then increases, CaSnO₃ doped BST ceramics are still the perovskite structure. When the mass fraction of CaSnO₃ doping amount is 6.0%, the BST ceramics possess good comprehensive properties: ε_r of 4963, tanδ of 0.0069, ΔC/C of +19.69% ～ -26.18%, and the capacitance temperature property is suited for Y5V.

Key words: Barium and strontium titanate; Capacitor ceramics; CaSnO₃; Doping; Dielectric properties ；Ceramics