Carbon Nanotube Linear Bearing Nanoswitches

Abstract

We exploit the remarkable low-friction bearing capabilities of multiwalled carbon nanotubes (MWNTs) to realize nanoelectromechanical switches. Our switches consist of two open-ended MWNT segments separated by a nanometer-scale gap. Switching occurs through electrostatically actuated sliding of the inner nanotube shells to close the gap, producing a conducting ON state. For double-walled nanotubes in particular, a gate voltage can restore the insulating OFF state. Acting as a nonvolatile memory element capable of several switching cycles, our devices are straightforward to implement, self-aligned, and do not require complex fabrication or geometries, allowing for convenient scalability.

Supermolecular switches based on multiwalled carbon nanotubes

“…[6][7] Electromechanical switches, relays, memories and logic elements represent another important family of devices that can be realized using telescoping nanobearings. [8][9][10][11][12][13] These devices compare favorably with other technologies in terms of size, power consumption and speed (estimated to be in the GHz regime). However, investigations of these electrostatically actuated telescoping devices has primarily been confined to theoretical studies, [8][9][10][11][12] and to date there has only been one experimental demonstration of this mechanism.…”

“…However, investigations of these electrostatically actuated telescoping devices has primarily been confined to theoretical studies, [8][9][10][11][12] and to date there has only been one experimental demonstration of this mechanism. 13 Recently, we presented a hybrid nanofabrication process to fabricate multiple, but spatially separated, capless nanotube segments from a single MWNT. 14 In this paper, we present electrostatically actuated NEMS switches using this construct, which represents an operational demonstration of a bi-directional nanobearing architecture (unidirectional constructs reported previously include [1][2]13]).…”

“…13 Recently, we presented a hybrid nanofabrication process to fabricate multiple, but spatially separated, capless nanotube segments from a single MWNT. 14 In this paper, we present electrostatically actuated NEMS switches using this construct, which represents an operational demonstration of a bi-directional nanobearing architecture (unidirectional constructs reported previously include [1][2]13]). Furthermore, our switches based on ultrasmall bearings (~200nm length) demonstrate lower actuation voltages (0.8 to 6V) as compared to those in ref.…”

Nanogap‐Engineerable Electromechanical System for Ultralow Power Memory

“…This method has previously been used to create nanoscale gaps in multiwalled carbon nanotubes and graphene 2, 5, 11, 12, 20. Due to the random nature of the electroburning process, if all part of the SWNT is suspended or adhered on the silicon substrate, the position of the gap in the SWNT is not well controlled.…”

“…Nanogap engineering of low‐dimensional nanomaterials has the potential to fulfill this need, provided their structures and properties at the moment of gap formation could be controlled, which has been of emerging interest in a variety of fields, ranging from molecular electronics to memories 2, 5, 6, 7, 8, 9, 10. Nanogaps also have wide applications in nanoelectromechanical switching (NEMS), where electrostatic forces are used to mechanically deflect an active element into physical contact with an electrode, thus changing the state of the device 11, 12, 13. Single‐walled carbon nanotubes (SWNTs) are 1D hollow structure, rolled by one‐atom‐thick graphene, which is a more promising material to act as the active element in NEMS 14, 15, 16, 17, 18, 19.…”