Synthesis and characterization of Ba^sub 0.7^Sr^sub 0.3^TiO3, BaZr^sub 0.3^Ti^sub 0.7^O3 thin film heterostructures

The paper presents synthesis of Ba^sub 0.7^Sr^sub 0.3^TiO3 (BST), Ba^sub 0.7^Sr^sub 0.3^TiO3 (BZT) thin films and BZT/BST heterostructures using modified Pechini method. The La^sub 0.7^Sr^sub 0.3^MnO3 has been used as a conducting bottom layer to form metal ferroelectric metal capacitor. The thin films are spin coated on SiO2/n-Si (100) substrates. The thin films thus deposited are characterized for crystal structure, morphology, dielectric and complex impedance properties. The results show that BZT/BST heterostructures show reduced loss tangent tan δ and useful value of figure of merit γ in RF range of frequencies. The results on dielectric properties could be analyzed in terms of the Maxwell-Wagner Model and contribution due to superlattice effects.[PUBLICATION ABSTRACT]