Ferroelectric Composite of Ba1−xSrxTiO3 With Al2O3 and MgO Synthesized by Sol-Gel Method

Abstract

AbstractBarium strontium titanate with low dielectric constant, low loss tangent and high tunability, has unique application as phase shifter in radar and antenna. This work presents an alternative fabrication of the composite of barium strontium titanate with metal oxides such as Al2O3 and MgO. Ba1−xSrxTiO3 (BST), xergels of various compositions (x = 0.2, 0.4, 0.5 and 0.6) were prepared by sol-gel method. Xerogels were calcined at 800 °C. The structure of the final powders was investigated by x-ray diffraction (XRD). The resultant BST was then mixed with metal oxides in the desired weight percentage and ball milled in an organic solvent (ethyl alcohol) with a binder (acrylic polymer). The final samples were sintered at 1250 °C in air. The dielectric properties of the composites were determined by using impedance analyzer at the frequency of 1MHz. This work has reported the effect of Al2O3 and MgO, on the electronic behavior of the final BST-metal oxide composites.