Microwave Dielectric Properties of Ca_1-3xLn_2xTiO₃ Ceramics

Ca_1-3xLn_2xTiO₃(x=0.13, 0.20;Ln=La, Nd, Sm) ceramics were prepared by solid state reaction method.The influences of Ln₃+ content on phase composition, microstructure and microwave dielectric properties of Ca_1-3xLn_2xTiO₃ ceramics were investigated.The results show that single orthogonal perovskite structure phase was formed except that a little secondary phase Sm₂Ti₂O₇ was detected by XRD analysis when x=0.20 and Ln=Sm.Dielectric constant(τ_f) and temperature coefficient of resonant frequency(τ_f) decreased with the increasing Ln₃+ content.The Ca_1-3xLn_2xTiO₃ ceramics with perferable microwave dielectric properties were obtained when x=0.13: ε=120, Qf=10700GHz, τ_f=304×10^-6/℃(Ln=La);