Multifunctional Eu3+-doped Bi12TiO20 thin films: Resistive switching, dielectric, and photoluminescent properties

摘要

Eu3+ -doped Bi12TiO20 thin films were prepared on Pt/Ti/SiO2/Si and fused silica substrates by a chemical solution deposition method. The thin films annealed at 600 degrees C crystallized in a sillenite structure with a uniform thickness. After an electroforming process, the resistive switching properties were observed in the thin films sandwiched with top and bottom Pt electrodes. The dominant conduction mechanisms in Pt/Bi10.8Eu1.2TiO20/Pt devices were Ohmic conduction at low resistance state and lower-voltage region of high resistance state, and Schottky emission at higher-voltage region in high resistance state. The dielectric and photoluminescent properties of the thin films have also been investigated. With increasing Eu3+ content, the dielectric constant increased and dielectric loss decreased due to improved crystallization of the thin films. Under 350 nm excitation, the thin films on fused silica substrates exhibited the visible emissions assigned to the transitions D-5(0)-> F-7(1,2) of Eu3+ ions. The results indicate that Eu3+ -doped Bi12TiO20 thin films are potential multifunctional materials which could be applied to optoelectronic thin film devices. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.