Carbon-based nano-electro-mechanical systems

Abstract

We provide an overview of our work where carbon-based nanostructures have been applied to twodimensional (2D) planar and three-dimensional (3D) vertically-oriented nano-electro-mechanical (NEM) switches. In the first configuration, laterally oriented single-walled nanotubes (SWNTs) synthesized using thermal chemical vapor deposition (CVD) were implemented for forming bridge-type 2D NEMS switches, where switching voltages were on the order of a few volts. In the second configuration, vertically oriented carbon nanofibers (CNFs) synthesized using plasma-enhanced (PE) CVD have been explored for their potential application in 3D NEMS. We have performed nanomechanical measurements on such vertically oriented tubes using nanoindentation to determine the mechanical properties of the CNFs. Electrostatic switching was demonstrated in the CNFs synthesized on refractory metallic nitride substrates, where a nanoprobe was used as the actuating electrode inside a scanning-electron-microscope. The switching voltages were determined to be in the tens of volts range and van der Waals interactions at these length scales appeared significant, suggesting such structures are promising for nonvolatile memory applications. A finite element model was also developed to determine a theoretical pull-in voltage which was compared to experimental results.

Cyclic Buckling Characterization of an Individual MWCNT Using Quantitative In Situ TEM Axial Compression

“…Among their many properties, CNT excel in high carrier mobility, conductivity, mechanical flexibility, and low weight [ 4 , 5 , 6 , 7 ]. These properties, together with their low production cost, make them appealing for flexible electronics, nanotube radios [ 8 ], nanotweezers [ 9 , 10 ], and high-frequency nanoelectromechanical systems (NEMS), such as nanoswitches [ 11 ], nanorelays [ 12 , 13 ] and nanoresonators [ 14 , 15 ].…”