Toward carbon nanotube-based AFM cantilevers

The mechanical properties of carbon nanotubes have been widely employed to enhance the performance of atomic force microscopy (AFM) cantilever tips. Utilizing the electromechanical properties of carbon nanotubes, this paper investigates the potential of using carbon nanotubes as active strain sensing elements on AFM cantilevers. A batch microfabrication process was developed to construct silicon microcantilevers. Multiwalled carbon nanotubes were dielectrophoretically assembled between electrodes. Based on the characterization results of 12 devices, the CNT-based cantilevers demonstrated a linear relationship between resistance changes and externally applied strain. The gauge factor ranged from 78.84 to 134.40 for four different device configurations.