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Novel electroforming-free nanoscaffold memristor with very high uniformity, tunability, and density.

Lee S, Sangle A, Lu P, Chen A, Zhang W, Lee JS, Wang H, Jia Q, MacManus-Driscoll JL - Adv. Mater. Weinheim (2014)

Bottom Line: The strategy is to design vertical interfaces using two structurally incompatible oxides, which are likely to generate a high-concentration oxygen vacancy.Non-linear electroresistance at room temperature is demonstrated using these nano scaffold devices.The resistance variations exceed two orders of magnitude with very high uniformity and tunability.

View Article: PubMed Central - PubMed

Affiliation: Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge, CB3 0FS, UK.

No MeSH data available.


Related in: MedlinePlus

Schematic diagrams of conventional methods to generate Vo¨. a) Irreversible electroforming with application of a high electrical stimulus to single-phase oxides. b) Conventional single-phase oxide film fractionally substituted with dopants. c) Conventional multilayer film causing oxygen disorder at the lateral heterointerfaces of dissimilar crystal structures. d) Nanoscaffold film causing oxygen vacancies at the vertical heterointerfaces of dissimilar crystal structures.
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fig01: Schematic diagrams of conventional methods to generate Vo¨. a) Irreversible electroforming with application of a high electrical stimulus to single-phase oxides. b) Conventional single-phase oxide film fractionally substituted with dopants. c) Conventional multilayer film causing oxygen disorder at the lateral heterointerfaces of dissimilar crystal structures. d) Nanoscaffold film causing oxygen vacancies at the vertical heterointerfaces of dissimilar crystal structures.

Mentions: In the virgin state of most single-phase oxides (either binary or ternary oxides), the concentration of oxygen vacancies (Vo¨ in the notation of Kröger and Vink8) is probably not enough to give ‘ionotronic’ (ionic + electronic) behavior. Depending on the device structures and applications, different approaches have been proposed to increase the Vo¨ concentration of oxides in virgin samples. For example, irreversible electroforming is usually required to generate percolating oxygen deficient phases with application of a high electrical stimulus to single-phase oxides (Figure1a).15,16 Since this electroforming is random and uncontrollable, the variation of device performance across the chip and from-chip-to-chip has been a formidable technical challenge.12 In addition, since electroforming is destructive, it frequently damages or even kills the devices,16 and presents very serious obstacles for practical devices. Another method to increase Vo¨ in single-phase oxide materials is partial substitution (Figure 1b) with dopants (e.g. Y-doped ZrO2 and Gd-doped CeO2).2 This method has been mainly used in oxide electrolytes working at very high temperature for solid oxide fuel cells and oxygen sensors. Higher mobility Vo¨ has been reported in lateral multilayers (Figure 1c).17 Oxygen disorder is observed at the lateral semicoherent heterointerfaces of dissimilar structures, thus providing large concentrations of Vo¨ distributed throughout lateral interfaces. However, it is difficult to adapt the lateral multilayers to circuit elements because the current flows in lateral directions, which results in inherently poor integration density. The artificial engineering of Vo¨ in ionotronic devices working at room temperature is still in the early stages.


Novel electroforming-free nanoscaffold memristor with very high uniformity, tunability, and density.

Lee S, Sangle A, Lu P, Chen A, Zhang W, Lee JS, Wang H, Jia Q, MacManus-Driscoll JL - Adv. Mater. Weinheim (2014)

Schematic diagrams of conventional methods to generate Vo¨. a) Irreversible electroforming with application of a high electrical stimulus to single-phase oxides. b) Conventional single-phase oxide film fractionally substituted with dopants. c) Conventional multilayer film causing oxygen disorder at the lateral heterointerfaces of dissimilar crystal structures. d) Nanoscaffold film causing oxygen vacancies at the vertical heterointerfaces of dissimilar crystal structures.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4225682&req=5

fig01: Schematic diagrams of conventional methods to generate Vo¨. a) Irreversible electroforming with application of a high electrical stimulus to single-phase oxides. b) Conventional single-phase oxide film fractionally substituted with dopants. c) Conventional multilayer film causing oxygen disorder at the lateral heterointerfaces of dissimilar crystal structures. d) Nanoscaffold film causing oxygen vacancies at the vertical heterointerfaces of dissimilar crystal structures.
Mentions: In the virgin state of most single-phase oxides (either binary or ternary oxides), the concentration of oxygen vacancies (Vo¨ in the notation of Kröger and Vink8) is probably not enough to give ‘ionotronic’ (ionic + electronic) behavior. Depending on the device structures and applications, different approaches have been proposed to increase the Vo¨ concentration of oxides in virgin samples. For example, irreversible electroforming is usually required to generate percolating oxygen deficient phases with application of a high electrical stimulus to single-phase oxides (Figure1a).15,16 Since this electroforming is random and uncontrollable, the variation of device performance across the chip and from-chip-to-chip has been a formidable technical challenge.12 In addition, since electroforming is destructive, it frequently damages or even kills the devices,16 and presents very serious obstacles for practical devices. Another method to increase Vo¨ in single-phase oxide materials is partial substitution (Figure 1b) with dopants (e.g. Y-doped ZrO2 and Gd-doped CeO2).2 This method has been mainly used in oxide electrolytes working at very high temperature for solid oxide fuel cells and oxygen sensors. Higher mobility Vo¨ has been reported in lateral multilayers (Figure 1c).17 Oxygen disorder is observed at the lateral semicoherent heterointerfaces of dissimilar structures, thus providing large concentrations of Vo¨ distributed throughout lateral interfaces. However, it is difficult to adapt the lateral multilayers to circuit elements because the current flows in lateral directions, which results in inherently poor integration density. The artificial engineering of Vo¨ in ionotronic devices working at room temperature is still in the early stages.

Bottom Line: The strategy is to design vertical interfaces using two structurally incompatible oxides, which are likely to generate a high-concentration oxygen vacancy.Non-linear electroresistance at room temperature is demonstrated using these nano scaffold devices.The resistance variations exceed two orders of magnitude with very high uniformity and tunability.

View Article: PubMed Central - PubMed

Affiliation: Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge, CB3 0FS, UK.

No MeSH data available.


Related in: MedlinePlus