Concept of nonvolatile memory based on multiwall carbon nanotubes

Abstract

In this study, a novel concept is proposed for molecular electronics that uses verticallyaligned multiwall carbon nanotubes as nonvolatile memory elements. Nanotubes grown ona patterned substrate may be opened by partially deleting the outer molecularlayer or layers, so that the inner core is able to move along the vertical tube axis.Mounting another dielectric plate above the nanotube forest at a specific distancefrom the tube caps can provide two stable van der Waals states of the inner core,providing for nonvolatile data storage. A device built using this architecture canfunction as a two-dimensional memory array. At each cross point in the array,a multiwall carbon nanotube exists in either the separated off-state or in thecontact on-state, and can be switched between these states by applying voltagepulses at the corresponding electrodes. A theoretical memory density as high as1013 memory elements per square centimetre is possible, with an operation frequency exceeding100 GHz. Significant physical characteristics of such a device are bi-stability andreversibility. Such a device can function both as nonvolatile random access memory and asterabit solid-state storage.