Fabrication of discrete nanoscaled force sensors based on single-walled carbon nanotubes

We present a fabrication technique for discrete, released carbon-nanotube-based nanomechanical force sensors. The fabrication technique uses prepatterned coordinate markers to align the device design to predeposited single-walled carbon nanotubes (SWNTs): Atomic force microscope (AFM) images are recorded to determine spatial orientation and location of each discrete nanotube to be integrated in a nanoscaled force sensor. Electron beam lithography is subsequently used to pattern the metallic electrodes for the nanoscale structures. Diluted hydrofluoric acid etching followed by critical point drying completes the nanosized device fabrication. We use discrete, highly purified, and chemically stable carbon nanotubes as active elements. We show AFM and scanning electron microscope images of the successfully realized SWNTs embedded nanoelectromechanical systems (NEMS). Finally, we present electromechanical measurements of the suspended SWNT NEMS structures.