Resistive switching and Schottky diode-like behaviors in Pt/BiFeO3/ITO devices

Yoon

ACS Appl. Mater. Interfaces

et al. 2016

The room-temperature resistive switching characteristics of ferroelectric, ferroelastic, and multiferroic materials are promising for application in nonvolatile memory devices. These resistive switching characteristics can be accompanied by a change in the ferroic order parameters via applied external electric and magnetic excitations. However, the dynamic evolution of the order parameters between two electrodes, which is synchronized with resistive switching, has rarely been investigated. In this study, for the first time, we directly monitor the ferroelectric/ferroelastic domain switching dynamics between two electrodes in multiferroic BiFeO (BFO) planar devices, which cause resistive switching, using piezoresponse force microscopy. It is demonstrated that the geometrical relationship between the ferroelectric domain and electrode in BFO planar capacitors with only 71° domain walls significantly affects both the ferroelectric domain dynamics and the resistive switching. The direct observation of domain dynamics relevant to resistive switching in planar devices may pave the way to a controllable combination of ferroelectric characteristics and resistive switching in multiferroic materials.

Section: ■ Results and Discussionmentioning

confidence: 99%

Direct Observation of Domain Motion Synchronized with Resistive Switching in Multiferroic Thin Films

Yoon

ACS Appl. Mater. Interfaces

et al. 2016

“…I – V characteristics are slightly asymmetric with respect to the bias and exhibit two conductive states such as high resistance state (HRS) and low resistance state (LRS). The asymmetric behavior of the I – V curve is due to the Schottky barrier formed at the interface between BST and ITO . The ferroelectric polarization orientation in BST thin films changes the charge distribution at the ferroelectric–semiconductor interface and modulates the Schottky barrier profile.…”

Section: Resultsmentioning

confidence: 99%

Light-controlled resistive switching in laser-assisted annealed Ba_0.8 Sr_0.2 TiO₃ thin films

Silva

Kamakshi

Sekhar

et al. 2015

Phys. Status Solidi A

In this work, Ba0.8Sr0.2TiO3 (BST)/ITO structures were grown on glass substrate and laser assisted annealing (LAA) was performed to promote the crystallization of BST. Atomic force microscopy and X‐ray diffraction studies confirm the crack free and polycrystalline perovskite phase of BST. White light controlled resistive switching (RS) effect in Au/BST/ITO device is investigated. The device displays the electroforming‐free bipolar RS characteristics and are explained by the modulation of the width and height of barrier at the BST/ITO interface via ferroelectric polarization. Moreover, the RS effect is significantly improved under white light illumination compared to that in the dark. The enhanced RS and photovoltaic effects are explained by considering depolarization field and charge distribution at the interface. The devices exhibit stable retention characteristics with low currents (≤μA), which make them attractive for non volatile memory devices.

Advances in Materials Science and Engineering

“…Electrically induced modulations on oxide/electrode interface barriers may also result in resistive switching [10,11]. Although such modulations can be achieved through electric-field-driven migrations of charged defects, ferroelectric switching provides a unique modulation mechanism in this respect, the switchable ferroelectric diode behavior, as first observed in BiFeO 3 -based devices [12,13]. In these devices, Schottky barriers are formed at both interfaces and the barrier heights can be switched to a high or a low level as a response to the switched bound charges at the interface due to ferroelectric switching.…”

Section: Introductionmentioning

confidence: 99%

Deposition-Parameter-Determined Resistive Switching Characteristics in TiO_x/Pb(Zr_0.52Ti_0.48)O₃Bilayers

Zhou

Luo

et al. 2015

Pb(Zr0.52Ti0.48)O3(PZT) ferroelectric thin films were deposited epitaxially, by pulsed laser deposition, on (001) SrTiO3substrates buffered with La0.7Sr0.3MnO3(LSMO) electrodes. AmorphousTiOxthin films were deposited on top of PZT at various temperatures and oxygen chamber pressures. Bipolar resistive switching characteristics of Pt/TiOx/PZT/LSMO heterostructures are found to vary withTiOxdeposition parameters, from an interface controlled ferroelectric diode behavior to a bulk-controlled conductive filament behavior. The observations are discussed in terms of the concentration and migration of oxygen vacancies in theTiOxlayer.