Electric force microscopy applications

Muller, F., et al. (1997), Applications of scanning electrical force microscopy, Micro-electron. ReliabU., 37(10-11), 1631-1634. 

Another widely used application of dynamic modes is the investigation of surface electrical characteristics. Electrical force microscopy (EFM) comprises a set of related techniques [70], and provides the possibility of probing locahzed charge distribution. 

The electrical property of CdSe nanofibres is an important aspect of the optoelectronic properties, which are dependent on quantum confinement effects. Electric force microscopy (EFM) was used to measure the dielectric behaviour of CdSe QDs to explore the use of the generated nanofibres in different applications [49]. The Coulomb interactions between the EFM probe and the CdSe nanoparticles were different to the ELP matrix. These reflected in form of a phase-shift of the cantilever oscillation [34]. This phase-shift resolves differences in the electrostatic interaction forces, as shown in Fig. 7. The EFM image shown in Fig. 7b, in comparison with the AFM image in Fig. 7a, reveals the alignment of discrete CdSe nanoparticles separated by the ELP shell within the nanofibres. 

The second application of noncontact AFM is in near-field detection of force gradients at 5-50 nm above the surface. This is the approach used in electric force microscopy (EFM) [158] and magnetic force microscopy (MFM) [159]. 

D. Sarid, Scanning Force Microscopy with Applications to Electric, Magnetic and Atomic Forces, Oxford University Press, New York, 1991. 

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. 

Several applications of scanning force microscopy (SFM) and related techniques in polymer science have been given in the above sections. The reviewed results were gathered from surfaces of cross-sectioned bulk polymers, polymer-matrix composites, and polymer blends as well as free surfaces of polymer samples such as films, or surfaces prepared by means of replica techniques. The materials contrasts reported on range from several mechanical ones via thermal to electrical ones. 

Sarid D (1991) Scanning force microscopy with applications to electric, magnetic and atomic forces. Oxford University Press, Oxford (ISBN 0-19-506270-1)... 

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