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Confining vertical conducting filament for reliable resistive switching by using a Au-probe tip as the top electrode for epitaxial brownmillerite oxide memristive device.

ABSTRACT: We had discovered novel resistance switching phenomena in SrCoOx epitaxial thin films. We have interpreted the results in terms of the topotactic phase transformation between their insulating brownmillerite phase and the conducting perovskite phase and the existence of a rather vertical conducting filament due to its inherent layered structure. However, the rough interface observed between the SrCoOx and the Au top electrode (area ~10000??m2) was assumed to result in the observed fluctuation in key switching parameters. In order to verify the effect of rough interface on the switching performance in the SrCoOx device, in this work, we studied the resistive switching properties of a SrCoOx device by placing a Au-coated tip (end area ~0.5??m2) directly on the film surface as the top electrode. The resulting device displayed much improved endurance and showed high uniformity in key switching parameters as compared to the device having a large top electrode area. A simulation result confirmed that the Au-coated tip provides a local confinement of the electrical field, resulting in confinement of oxygen ion distribution and therefore localization of the conducting filament. By minimizing other free and uncontrollable parameters, the designed experiment here provides the most direct and isolated evidence that the rough interface between electrode and ReRAM matrix is detrimental for the reproducibility of resistivity switching phenomena.

SUBMITTER: Nallagatla VR

PROVIDER: S-EPMC6362224 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Real-time device-scale imaging of conducting filament dynamics in resistive switching materials.

Project description:ReRAM is a compelling candidate for next-generation non-volatile memory owing to its various advantages. However, fluctuation of operation parameters are critical weakness occurring failures in 'reading' and 'writing' operations. To enhance the stability, it is important to understand the mechanism of the devices. Although numerous studies have been conducted using AFM or TEM, the understanding of the device operation is still limited due to the destructive nature and/or limited imaging range of the previous methods. Here, we propose a new hybrid device composed of ReRAM and LED enabling us to monitor the conducting filament (CF) configuration on the device scale during resistive switching. We directly observe the change in CF configuration across the whole device area through light emission from our hybrid device. In contrast to former studies, we found that minor CFs were formed earlier than major CF contributing to the resistive switching. Moreover, we investigated the substitution of a stressed major CF with a fresh minor CF when large fluctuation of operation voltage appeared after more than 50 times of resistive switching in atmospheric condition. Our results present an advancement in the understanding of ReRAM operation mechanism, and a step toward stabilizing the fluctuations in ReRAM switching parameters.

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In situ imaging of the conducting filament in a silicon oxide resistive switch.

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Memristive tonotopic mapping with volatile resistive switching memory devices.

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Parylene Based Memristive Devices with Multilevel Resistive Switching for Neuromorphic Applications.

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Atomic View of Filament Growth in Electrochemical Memristive Elements.

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Water-Mediated Ionic Migration in Memristive Nanowires with a Tunable Resistive Switching Mechanism.

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| S-EPMC8014891 | biostudies-literature

New Lutetium Oxide: Electrically Conducting Rock-Salt LuO Epitaxial Thin Film.

Project description:C-rare earth structure lutetium sesquioxide Lu2O3 has been recognized as a high-k widegap insulator with closed shell Lu3+ ions. In this study, rock-salt structure lutetium monoxide LuO with unusual valence of Lu2+ (4f145d1), previously known as the gaseous phase, was synthesized as an epitaxial thin film by the pulsed laser deposition method. In contrast with transparent and highly insulating Lu2O3, LuO possessed a dark-brown color and high electrical conductivity concomitant with strong spin-orbit coupling as a manifestation of Lu 5d electron carriers.

| S-EPMC6644888 | biostudies-literature

Enhancing Reliability of Studies on Single Filament Memristive Switching via an Unconventional cAFM Approach.

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Large area molybdenum disulphide- epitaxial graphene vertical Van der Waals heterostructures.

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