Non-volatile resistive switching in oxide ion conductor BiYO3 thin films

Abstract

We experimentally demonstrate non-volatile resistive switching (RS) with a resistance window of ∼10× in oxide ion conductor BiYO3 (BYO) thin films. (111)-oriented BYO films of multiple thicknesses (20 nm–300 nm) were deposited using the pulsed laser deposition technique on a Pt/TiO2/SiO2/Si substrate. The thermal stability of BYO films in a wide temperature range (10 K–800 K) was confirmed, using temperature dependent dielectric measurements. Further, impedance spectroscopy suggests the presence of oxygen vacancies (defects) at the Au/BYO interface in the high resistance state (after forming) too. Root mean square roughness of the films varied from 1.16 nm to 2.76 nm, confirming a uniform and homogeneous surface. We explain the conduction mechanism in our Au/BYO/Pt devices using space charge limited current (SCLC) and Ohmic conduction models. The bipolar RS characteristics of the BYO devices are empirically modeled on the basis of the oxygen ion driven filamentary switching process.