Atomic lateral force microscopy

In 1987 Mate et al. [468] used, for the first time, an atomic force microscope (AFM) to measure friction forces on the nanometer scale (review Ref. [469]). This technique became known as friction force microscopy (FFM) or lateral force microscopy (LFM). To measure friction forces with the AFM, the fast scan direction of the sample is chosen perpendicular to the direction of the cantilever. Friction between the tip and the sample causes the flexible cantilever to twist (Fig. 11.7). This torsion of the cantilever is measured by using a reflected beam of light and a position-sensitive detector in the form of a quadrant arrangement of photodiodes. This new method made it possible for the first time to study friction and lubrication on the nanometer scale. 

To further miniaturize the sensors, nanotechniques such as surface probe microscopy and lithography, lateral force microscopy, atomic force microscopy (AFM), and AFM lithography can be utilized.46 Nanoimprint lithography is a low-cost technique that has been shown to produce patterns on the nanometer scale.98 99... 

Abstract. Quantitative measurements of lateral force required for displacement of SWNTs bundle on the surface of highly oriented pyrolytic graphite with the help of atomic force microscope (AFM) were performed in real time . New method of quantitative calibration of lateral forces was used for interpretation results of lateral force microscopy (LFM). It allows us to receive numerical values of adhesion force of bundle to substrate easy and without specific equipment. 

Keywords Carbon nanotubes, Lateral force microscopy, Atomic force microscopy. 

Atomic force microscopy [6, 7] is one of the most suitable methods for research carbon nanotubes. AFM allows to receive not only a relief of the studied sample, but also distribution of mechanical characteristics, electric, magnetic and other properties on its surface. With the help of AFM, controllable manipulation of individual CNTs and CNTs bundles became possible. In this paper we report our approach to manipulating SWCNTs bundles with lateral force microscopy. LFM gives possibility to study lateral forces that probe acts upon bundles. In spite of good visualization of LFM, its lack is absence of reliable techniques of quantitative interpretation of results. The new way of calibration developed ourselves has allowed to pass from qualitative estimations to quantitative investigations [8], The given calibration technique is much more exact, than others known till now [9, 10], and does not assume simplification. With the help of new technique we may study adhesion of bundles to substrate and adhesion of CNTs in bundle qualitatively in real time more easy way. This result will provide new possibilities for nanotube application. 

SPM, any of the methods tabulated STM, scanning tunneling microscopy AFM, atomic force microscopy LFM, lateral force microscopy dF/ds, stiffness. 

The dimension of the resultant structure was visualized by atomic force microscopy (AFM). Indeed, the width of the fibers was reduced compared to that of SAF peptides however, its length was much more heterogeneous. Most fibers were also shown to be shorter than that of previously described coiled coil nanofibers. Fiber shortening could be related to the 1) weak association between sticky-ended coiled coils and 2) salt effects. It was found that sodium chloride and ammonium sulfate have a distinct effect on the fibril lateral aggregation, leading to short fibers in NaCl and long fibers in ammonium sulfate. 

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