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Carbon nanomaterials for non-volatile memories

Abstract

Carbon can create various low-dimensional nanostructures with remarkable electronic, optical, mechanical and thermal properties. These features make carbon nanomaterials especially interesting for next-generation memory and storage devices, such as resistive random access memory, phase-change memory, spin-transfer-torque magnetic random access memory and ferroelectric random access memory. Non-volatile memories greatly benefit from the use of carbon nanomaterials in terms of bit density and energy efficiency. In this Review, we discuss sp2-hybridized carbon-based low-dimensional nanostructures, such as fullerene, carbon nanotubes and graphene, in the context of non-volatile memory devices and architectures. Applications of carbon nanomaterials as memory electrodes, interfacial engineering layers, resistive-switching media, and scalable, high-performance memory selectors are investigated. Finally, we compare the different memory technologies in terms of writing energy and time, and highlight major challenges in the manufacturing, integration and understanding of the physical mechanisms and material properties.

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Figure 1: Carbon nanotubes as crossbar electrodes.
Figure 2: Carbon nanomaterials as edge electrodes.
Figure 3: Graphene as an interfacial engineering layer.
Figure 4: Carbon nanotube field-effect transistors for high-density non-volatile memory crossbar arrays.
Figure 5: Graphene oxide and other carbon-based composites.
Figure 6: Ashby plot for non-volatile memories.

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Acknowledgements

This work was supported by The University of Texas System Faculty Science and Technology Acquisition and Retention (STARs), Defense Advanced Research Projects Agency (DARPA) (MTO, ‘Revolutionizing Data-Intensive Computing’), the National Science Foundation (NSF) CAREER grant 1430530, the member companies of the Stanford Non-volatile Memory Technology Research Initiative (NMTRI) and the Stanford SystemX Alliance. The authors thank C. M. Neumann for his contribution to collecting the data in Table 1.

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Ahn, E., Wong, HS. & Pop, E. Carbon nanomaterials for non-volatile memories. Nat Rev Mater 3, 18009 (2018). https://doi.org/10.1038/natrevmats.2018.9

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