AFM imaging

Fig. XVin-3. AFM image of DNA strands on mica. Lower figure image obtained in the contact mode under water. The contrast shown covers height variations in the range of 0-2 nm. Upper figure observed profile along the line A-A of the lower figure. (From S. N. Magnov and M.-H. Whangbo, Surface Analysis with STM and AFM, VCH, New Yoric, 1996.)...

Figure Bl.19.19. Examples of inaccessible features in AFM imaging. L corresponds to the AFM tip. The dotted curves show the image that is recorded in the case of (a) depressions on the underside of an object and (b) mounds on the top surface of an object. M- L andMoi correspond to convolutions of the surface features with the tip shape. (Taken from [ ], figure 2.)...

Figure Bl.19.25. AFM image of Si(l 11)-(7 x 7) taken in the AC mode. Contrast ean be observed between inequivalent adatoms. Image eourtesy of R Erlandsson. (Taken from [217], figure 4.)...

Figure Bl.19.26. Highly resolved, non-eontaet AFM image of the TiO2(110)-(l x l) surfaee (8.5 x 8.5 imr)...

Figure Bl.19.29. AFM image of poly sty rene/poly butadiene copolymer, showing lamellar stnicture. (Taken ftom [140], figure 1.)...

Figure Bl.19.31. AFM image of a 2.7 mn x 2.7 mn area of a polypropylene surfaee, displaying metiiyl groups and right- and left-handed heliees. (Taken from [143]. figure 10.)...

Allen M J, Hud N V, Balooch M, Tench R J, Siekhaus W J and Balhorn R 1992 Tip-radius-induced artifacts in AFM images of protamine-complexed DMA fibers Ultramicroscopy 42-A4 1095... 

Fig. 5.9. AFM image of a Lavsan filtration membrane. Image size 5 )xm x 5 )xm, depth scale 500 nm from black to white.

Fig. 5.10. Series of sequential in-situ AFM images of the growth of ODS on silicon. The numbers indicate the adsorption time in minutes.

Numerous AFM imaging techniques have been developed and commercialized to monitor topography, friction, mechanical response, capacitance, magnetic properties, etc. However, adhesion measurements require the tip to come into, and out of, contact to measure attractive and adhesion forces. Therefore, other than to select an analysis region, most imaging techniques are not useful for adhesion studies. Instead, measurements are necessarily based on force-displacement curve approaches. 

Whereas XRD patterns of the thin crystalline films provide information on the orientation and lattice distances perpendicular to the substrate, AFM has proven to be a powerful technique for obtaining structural information of thin-lilm surfaces of conjugated materials 195 j. AFM imaging of the surface of a thin (10 nm) annealed film of Ooct-OFV5 confirmed the domain structure of the annealed Ooct-... 

The framework we adopted for measuring the scaling behavior from AFM images is the following. The 2-D power spectral density (PSD) of the Fast Fourier Transform of the topography h(x, y) is estimated [541, then averaged over the azimuthal angle

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AFM images of PET film surfaces have also recently been measured [156] and they showed a microroughness of PET films of the order of 1 nm averaged over a surface area of 200 x 200 nmJ. In some cases atomic lateral resolution is achieved [39] when e.g. dialkylamonium (C16) layers adsorbed on mica from cyclohexane are examined [157]. The interpretation of AFM data is at present not always clear and further advances will be made with improved instrumentation. Up till now, only very specific examples of polymeric structure have been investigated,... 

Fig. 31—Surface AFM image for Ni-P coating polished by AI2O3 slurry.

FIGURE 12.10 Tapping mode atomic force microscopy (AFM) images of the section analyzes of ethylene-propylene-diene monomer (EPDM) rubber-melamine fiber composites. A, composite containing no dry bonding system B, composite containing resorcinol, hexamine, and silica in the concentrations 5, 3, and 15 phr, respectively. 

In this part, we will discuss AFM images and nanomechanical data obtained in smdies of natural and synthetic rubbers, thermoplastic elastomers (TPE), and their vulcanized counterparts— thermoplastic vulcanizates (TPV). 

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