Structural and dielectric properties of calcium doped bismuth zinc niobate thin films prepared by pulsed laser deposition at room temperature

摘要

(Bi1.5Zn0.1Ca0.4)(Zn0.5Nb1.5)O-7 (BZNCa) thin films were prepared by pulsed laser deposition on Pt/TiO2/SiO2/Si substrates at room temperature. The as-deposited films and films post-annealed from 100 degrees C to 175 degrees C for 10 min in air are all amorphous. The influence of the post-annealing process on structural and electrical properties was investigated. The surface morphology of BZNCa films remains almost same with the annealing temperature. While the dielectric and leakage-current properties of the films are strongly influenced by the annealing temperature. The film deposited at O-2 pressure of 4 Pa and then post-annealed at 150 degrees C shows the improved dielectric and leakage-current characteristics. The dielectric constant and loss tangent are 67.2 and 0.03 at 100 kHz, respectively. The leakage current density is less than 1 mu A/cm(2) at an applied bias electric field of 400 kV/cm. The results indicate that calcium doped BZN thin films have potential applications for embedded capacitors. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.