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Title: Structural changes and conductance thresholds in metal-free intrinsic SiO{sub x} resistive random access memory

Abstract

We present an investigation of structural changes in silicon-rich silicon oxide metal-insulator-metal resistive RAM devices. The observed unipolar switching, which is intrinsic to the bulk oxide material and does not involve movement of metal ions, correlates with changes in the structure of the oxide. We use atomic force microscopy, conductive atomic force microscopy, x-ray photoelectron spectroscopy, and secondary ion mass spectroscopy to examine the structural changes occurring as a result of switching. We confirm that protrusions formed at the surface of samples during switching are bubbles, which are likely to be related to the outdiffusion of oxygen. This supports existing models for valence-change based resistive switching in oxides. In addition, we describe parallel linear and nonlinear conduction pathways and suggest that the conductance quantum, G{sub 0}, is a natural boundary between the high and low resistance states of our devices.

Authors:
; ; ; ; ;  [1]; ; ;  [2]
  1. Department of Electronic and Electrical Engineering, UCL, Torrington Place, London WC1E 7JE (United Kingdom)
  2. Department of Materials, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom)
Publication Date:
OSTI Identifier:
22399349
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 12; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ATOMIC FORCE MICROSCOPY; ELECTRIC CONDUCTIVITY; ION MICROPROBE ANALYSIS; IONS; MASS SPECTROSCOPY; METALS; NONLINEAR PROBLEMS; OXYGEN; RANDOMNESS; SILICON; SILICON OXIDES; SURFACES; VALENCE; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Mehonic, Adnan, E-mail: a.mehonic@ee.ucl.ac.uk, E-mail: t.kenyon@ucl.ac.uk, Buckwell, Mark, Montesi, Luca, Garnett, Leon, Hudziak, Stephen, Kenyon, Anthony J., E-mail: a.mehonic@ee.ucl.ac.uk, E-mail: t.kenyon@ucl.ac.uk, Fearn, Sarah, Chater, Richard, and McPhail, David. Structural changes and conductance thresholds in metal-free intrinsic SiO{sub x} resistive random access memory. United States: N. p., 2015. Web. doi:10.1063/1.4916259.
Mehonic, Adnan, E-mail: a.mehonic@ee.ucl.ac.uk, E-mail: t.kenyon@ucl.ac.uk, Buckwell, Mark, Montesi, Luca, Garnett, Leon, Hudziak, Stephen, Kenyon, Anthony J., E-mail: a.mehonic@ee.ucl.ac.uk, E-mail: t.kenyon@ucl.ac.uk, Fearn, Sarah, Chater, Richard, & McPhail, David. Structural changes and conductance thresholds in metal-free intrinsic SiO{sub x} resistive random access memory. United States. doi:10.1063/1.4916259.
Mehonic, Adnan, E-mail: a.mehonic@ee.ucl.ac.uk, E-mail: t.kenyon@ucl.ac.uk, Buckwell, Mark, Montesi, Luca, Garnett, Leon, Hudziak, Stephen, Kenyon, Anthony J., E-mail: a.mehonic@ee.ucl.ac.uk, E-mail: t.kenyon@ucl.ac.uk, Fearn, Sarah, Chater, Richard, and McPhail, David. 2015. "Structural changes and conductance thresholds in metal-free intrinsic SiO{sub x} resistive random access memory". United States. doi:10.1063/1.4916259.
@article{osti_22399349,
title = {Structural changes and conductance thresholds in metal-free intrinsic SiO{sub x} resistive random access memory},
author = {Mehonic, Adnan, E-mail: a.mehonic@ee.ucl.ac.uk, E-mail: t.kenyon@ucl.ac.uk and Buckwell, Mark and Montesi, Luca and Garnett, Leon and Hudziak, Stephen and Kenyon, Anthony J., E-mail: a.mehonic@ee.ucl.ac.uk, E-mail: t.kenyon@ucl.ac.uk and Fearn, Sarah and Chater, Richard and McPhail, David},
abstractNote = {We present an investigation of structural changes in silicon-rich silicon oxide metal-insulator-metal resistive RAM devices. The observed unipolar switching, which is intrinsic to the bulk oxide material and does not involve movement of metal ions, correlates with changes in the structure of the oxide. We use atomic force microscopy, conductive atomic force microscopy, x-ray photoelectron spectroscopy, and secondary ion mass spectroscopy to examine the structural changes occurring as a result of switching. We confirm that protrusions formed at the surface of samples during switching are bubbles, which are likely to be related to the outdiffusion of oxygen. This supports existing models for valence-change based resistive switching in oxides. In addition, we describe parallel linear and nonlinear conduction pathways and suggest that the conductance quantum, G{sub 0}, is a natural boundary between the high and low resistance states of our devices.},
doi = {10.1063/1.4916259},
journal = {Journal of Applied Physics},
number = 12,
volume = 117,
place = {United States},
year = 2015,
month = 3
}
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