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Title: On the origin of resistive switching volatility in Ni/TiO{sub 2}/Ni stacks

Abstract

Resistive switching and resistive random access memories have attracted huge interest for next generation nonvolatile memory applications, also thought to be able to overcome flash memories limitations when arranged in crossbar arrays. A cornerstone of their potential success is that the toggling between two distinct resistance states, usually a High Resistive State (HRS) and a Low Resistive State (LRS), is an intrinsic non-volatile phenomenon with the two states being thermodynamically stable. TiO{sub 2} is one of the most common materials known to support non-volatile RS. In this paper, we report a volatile resistive switching in a titanium dioxide thin film sandwiched by two nickel electrodes. The aim of this work is to understand the underlying physical mechanism that triggers the volatile effect, which is ascribed to the presence of a NiO layer at the bottom interface. The NiO layer alters the equilibrium between electric field driven filament formation and thermal enhanced ion diffusion, resulting in the volatile behaviour. Although the volatility is not ideal for non-volatile memory applications, it shows merit for access devices in crossbar arrays due to its high LRS/HRS ratio, which are also briefly discussed.

Authors:
; ; ;  [1]
  1. Nano Research Group, Electronics and Computer Science, University of Southampton, Southampton, Hampshire, SO17 1BJ (United Kingdom)
Publication Date:
OSTI Identifier:
22597707
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; DIFFUSION; ELECTRIC FIELDS; ELECTRODES; EQUILIBRIUM; FILAMENTS; IONS; LAYERS; NICKEL; NICKEL OXIDES; ORIGIN; STACKS; THIN FILMS; TITANIUM; TITANIUM OXIDES; VOLATILITY

Citation Formats

Cortese, Simone, E-mail: simone.cortese@soton.ac.uk, Trapatseli, Maria, Khiat, Ali, and Prodromakis, Themistoklis. On the origin of resistive switching volatility in Ni/TiO{sub 2}/Ni stacks. United States: N. p., 2016. Web. doi:10.1063/1.4960690.
Cortese, Simone, E-mail: simone.cortese@soton.ac.uk, Trapatseli, Maria, Khiat, Ali, & Prodromakis, Themistoklis. On the origin of resistive switching volatility in Ni/TiO{sub 2}/Ni stacks. United States. doi:10.1063/1.4960690.
Cortese, Simone, E-mail: simone.cortese@soton.ac.uk, Trapatseli, Maria, Khiat, Ali, and Prodromakis, Themistoklis. Sun . "On the origin of resistive switching volatility in Ni/TiO{sub 2}/Ni stacks". United States. doi:10.1063/1.4960690.
@article{osti_22597707,
title = {On the origin of resistive switching volatility in Ni/TiO{sub 2}/Ni stacks},
author = {Cortese, Simone, E-mail: simone.cortese@soton.ac.uk and Trapatseli, Maria and Khiat, Ali and Prodromakis, Themistoklis},
abstractNote = {Resistive switching and resistive random access memories have attracted huge interest for next generation nonvolatile memory applications, also thought to be able to overcome flash memories limitations when arranged in crossbar arrays. A cornerstone of their potential success is that the toggling between two distinct resistance states, usually a High Resistive State (HRS) and a Low Resistive State (LRS), is an intrinsic non-volatile phenomenon with the two states being thermodynamically stable. TiO{sub 2} is one of the most common materials known to support non-volatile RS. In this paper, we report a volatile resistive switching in a titanium dioxide thin film sandwiched by two nickel electrodes. The aim of this work is to understand the underlying physical mechanism that triggers the volatile effect, which is ascribed to the presence of a NiO layer at the bottom interface. The NiO layer alters the equilibrium between electric field driven filament formation and thermal enhanced ion diffusion, resulting in the volatile behaviour. Although the volatility is not ideal for non-volatile memory applications, it shows merit for access devices in crossbar arrays due to its high LRS/HRS ratio, which are also briefly discussed.},
doi = {10.1063/1.4960690},
journal = {Journal of Applied Physics},
number = 6,
volume = 120,
place = {United States},
year = {Sun Aug 14 00:00:00 EDT 2016},
month = {Sun Aug 14 00:00:00 EDT 2016}
}
  • Nanoscale multilayer structure TiO{sub 2}/BaTiO{sub 3}/TiO{sub 2} has been fabricated on Pt/Ti/SiO{sub 2}/Si substrate by chemical solution deposition method. Highly uniform bipolar resistive switching (BRS) characteristics have been observed in Pt/TiO{sub 2}/BaTiO{sub 3}/TiO{sub 2}/Pt cells. Analysis of the current-voltage relationship demonstrates that the space-charge-limited current conduction controlled by the localized oxygen vacancies should be important to the resistive switching behavior. X-ray photoelectron spectroscopy results indicated that oxygen vacancies in TiO{sub 2} play a crucial role in the resistive switching phenomenon and the introduced TiO{sub 2}/BaTiO{sub 3} interfaces result in the high uniformity of bipolar resistive switching characteristics.
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