title: Forming-free resistive switching in multiferroic BiFeO3 thin films with enhanced nanoscale shunts.
abstract: A controlled shunting of polycrystalline oxide thin films on the nanometer length scale opens the door to significantly modify their transport properties. In this paper, the low energy Ar(+) irradiation induced shunting effect of forming-free, non-volatile resistive switching in polycrystalline BiFeO3 thin film capacitor-like structures with macroscopic bottom and top contacts was investigated. Oxygen atoms at the BiFeO3 surface are preferentially sputtered by Ar(+) ion irradiation and oxygen vacancies and a metallic Bi phase are formed at the surface of the BiFeO3 thin film before deposition of the top contacts. A phenomenological model is that of nanoscale shunt resistors formed in parallel to the actual BiFeO3 thin film capacitor-like structure. This model fits the noticeable increase of the retention stability and current density after irradiation. The formation of stable and conductive shunts is further evidenced by conductive atomic force microscopy measurements.
authors.affiliation: Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf (HZDR) e.V. , P.O. Box 510119, 01314 Dresden, Germany.
authors.forename: Xin
authors.initials: X
authors.lastname: Ou
authors.forename: Yao
authors.initials: Y
authors.lastname: Shuai
authors.forename: Wenbo
authors.initials: W
authors.lastname: Luo
authors.forename: Pablo F
authors.initials: PF
authors.lastname: Siles
authors.forename: Reinhard
authors.initials: R
authors.lastname: Kögler
authors.forename: Jan
authors.initials: J
authors.lastname: Fiedler
authors.forename: Helfried
authors.initials: H
authors.lastname: Reuther
authors.forename: Shengqiang
authors.initials: S
authors.lastname: Zhou
authors.forename: René
authors.initials: R
authors.lastname: Hübner
authors.forename: Stefan
authors.initials: S
authors.lastname: Facsko
authors.forename: Manfred
authors.initials: M
authors.lastname: Helm
authors.forename: Thomas
authors.initials: T
authors.lastname: Mikolajick
authors.forename: Oliver G
authors.initials: OG
authors.lastname: Schmidt
authors.forename: Heidemarie
authors.initials: H
authors.lastname: Schmidt