Carbon Nanotube Atomic Force Microscopy with Applications to Biology and Electronics

Abstract

Carbon nanotube (CNT) possesses many desirable properties – electrical conductivity, high mechanical strength combined with ductility, chemical inertness, high aspect ratio, and resistance to wear. These same attributes can extend the capabilities of Atomic Force Microscopy (AFM) beyond the limits imposed by conventional silicon and silicon nitride AFM tips. In this chapter, we will give a brief introduction to the chemical, mechanical, and electrical properties of CNT. Following this will be techniques for fabrication of CNT tips and then a detailed discussion of methods for characterizing CNT AFM tip performance with respect to resolution, tip conductivity, three-dimensional imaging, and long-term reliability, including recently reported performance metrics for CNT tips used in Scanning Probe Microscopy (SPM) imaging studies. A survey of the application of CNT probes to a diverse array of AFM imaging modes such as Chemical Force Microscopy, Electric Force Microscopy, Friction Force Microscopy, Scanning Tunneling Microscopy, Magnetic Force Microscopy, and Scanning Near-Field Optical Microscopy highlights the advantages and performance improvements of using CNT AFM probes over conventional silicon probes. Finally, a presentation of the biological applications of CNT AFM probes illustrates the CNT probe’s present use in aggressive imaging of soft, fragile, feature-rich samples and potential use in targeted nanoscale drug-delivery.