Effect of heat treatment time on the dielectric properties of BST

Abstract

Structural and microstructural properties of sol gel processed BS_xT (x = 0.0, 0.05) ceramics have been investigated. Dielectric properties of these ceramics have also been studied as functions of frequency          [1kHz-2MHz] at different measurement temperatures (30-200°C). Heat treatment duration effect on dielectric properties and structural ones has been investigated. The results show that heat treatment and its duration has significant effects on structural, dielectric properties and the average grain size of the samples. Scanning electron microscopy (SEM) analysis show quite regular morphology of the grains and an average grain size which decreases with introduction of Sr, in agreement with structural characterization. Raman analysis has given results which are in accordance of XRD and SEM characterizations. Moreover, the permittivity variations as functions of the frequency, show a decrease in the interval [1kHz-100kHz], followed by an anormal increase in the interval [100kHz-1MHz].

Keywords: Structural, XRD, Raman, Dielectric properties