The influence of the thickness of TiO₂seeding layer on structural and electrical properties of Bi_3.15Nd_0.85Ti₃O₁₂thin films

Abstract

Thin films of Bi3.15Nd0.85Ti3O12(BNT) and BNT with various TiO2 seeding layer thicknesses BNT-Tx (x = 10, 20, 30 nm) were fabricated on Pt/Ti/SiO2/Si substrates by the sol–gel method. The influence of the TiO2 seeding layer thickness on the structural and the electrical properties of BNT thin films was investigated. The x-ray diffraction pattern indicated that the BNT thin film with a TiO2 seeding layer showed a-axis preference orientation. The Pr value was a maximum for the BNT-T20 film and decreased with both decreasing and increasing thickness. The BNT-T20 film had the largest er and the lowest tanδ. The leakage current density of the BNT thin films with various TiO2 seeding layer thicknesses was generally in the order of 10−6–10−5 A cm−2. The surface micrograph of BNT-Tx films was more homogeneous and dense than that without a seeding layer.