Structural and dielectric properties of Ba6−3xNd8+2xTi18O54 (x = 2/3) thin films processed by sol–gel technique

Abstract

Ba6−3xNd8+2xTi18O54 (x = 2/3, BNT) thin films were obtained by the Pechini sol–gel technique on the Si and Pt/Ti/SiO2/Si substrates. The heat treatment schedule was researched by differential scanning calorimetry and thermal gravimetry. The effects of annealing temperature on crystallinity and morphological characteristic were investigated by X-ray diffraction and scanning electron microscope. The results show that a crystallized thin film with a tungsten bronze structure was obtained by annealing the films at 950 °C. With the aid of 2 wt% B2O3–2SiO2 addition, the crystallization temperature decreased to 900 °C. The dielectric characteristics measurement showed that the dielectric constant and the dielectric loss of the BNT thin films were 45.2 and 0.011 at 1 MHz frequency, the leakage current density was 4.13 × 10−6 A/cm2 at bias of 30 V.