Modelling the switching effect in graphene oxide-based memristors

• Published in: Semiconductor science and technology Vol. 35; no. 5; pp. 55020 - 55026
• Main Authors: Vercik, Andrés, de Oliveira Vercik, Luci Cristina
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.05.2020
• Subjects: current-voltage characteristics; graphene oxide; memristor; metal-insulator-metal structures; switching mechanisms
• ISSN: 0268-1242; 1361-6641
• DOI: 10.1088/1361-6641/ab7a09

The two-dimensionality of insulating graphene oxide sheets is attractive for use in nanoscale two-terminal devices. These structures are promising for the next generation of non-volatile resistive random access memories, with high speed, low-power consumption and excellent scalability. In this work, the transport properties of graphene oxide-based metal-insulator-metal structures are addressed. The graphene oxide was synthesized using an eco-friendly modified Hummers method. The obtained graphene oxide sheets, placed between two electrodes, were subjected to an electrical characterization measuring cycling current-voltage (I-V) curves by applying successive forward and reverse voltage sweeps. When the absolute value of the measured current is plotted in logarithmic scale versus the applied voltage, the typical butterfly-shaped curves are observed, which are better interpreted in terms of their first derivative, or differential conductivity, in order to understand the transport mechanism. The experimental I-V curves can be explained in two different ways: by modifying well-known transport models or by using typical flux-controlled memristor models. The connection between both strategies is established in this work. The analytical expressions used for the differential conductance for the low resistance state and the high resistance state lead to simple expressions for the I-V curves. The symmetry of the curves after several cycles is lost when compared to those measured on pristine devices, which might indicate the occurrence of filament forming effect, affecting the bipolar switching.