Orientation imaging microscopy

Another new and much used variant is a procedure called orientation imaging microscopy (Adams ci al. 199.5) patterns created by electrons back-scattered from a grain are automatically interpreted by a computer program, then the grain examined is automatically changed, and finally the orientations so determined are used to create an image of the polycrystal with the grain boundaries colour- or thickness-... 

Orientation Imaging Microscopy D J Dingley, D P Field and S I Wright... 

D. H., (2004), Orientation imaging microscopy in two-dimensional crystals via undersampled microscopy , Appl. Phys. A - Materials Science and Processing, 78 (3) 387-392. 

Other names instead of EBSD are Backscatter Kikuchi Diffraction (BKD), Electron Backscatter Pattern Technique (EBSP), Orientation Imaging Microscopy (OIM ), or Automated Crystal Orientation Mapping (ACOM). In combination with electrochemical studies only ex situ applications are possible. 

The microstructure described above may be seen as the most homogeneous limit of those we will consider here. A complementary set of information concerning microstructures of the type featured above can be obtained by mapping the orientations of the various grains making up the polycrystal. The basic idea is that one may determine the preponderance of different crystal orientations. The new technique of orientation imaging microscopy now allows for the determination of such orientational information with high spatial resolution. An example of the type of results that are obtained via this technique is shown in fig. 10.3. 

Orientation imaging microscopy (OIM) maps were obtained from electron backscattering diffraction pattern (EBSP) using JEOL JXA8100 electron probe micro-analyzer with OIM software provided by TexSEM Lab., Inc. 

Snetivy D and Vancso G J 1994 Atomic force microscopy of polymer crystals 7. Chain packing, disorder and imaging of methyl groups in oriented isotactic polypropylene Po/yme/ 35 461... 

Figure Bl.22.11. Near-field scanning optical microscopy fluorescence image of oxazine molecules dispersed on a PMMA film surface. Each protuberance in this three-dimensional plot corresponds to the detection of a single molecule, the different intensities of those features being due to different orientations of the molecules. Sub-diffraction resolution, in this case on the order of a fraction of a micron, can be achieved by the near-field scaiming arrangement. Spectroscopic characterization of each molecule is also possible. (Reprinted with pennission from [82]. Copyright 1996 American Chemical Society.)...

Microscopy methods based on nonlinear optical phenomena that provide chemical information are a recent development. Infrared snm-frequency microscopy has been demonstrated for LB films of arachidic acid, allowing for surface-specific imaging of the lateral distribution of a selected vibrational mode, the asymmetric methyl stretch [60]. The method is sensitive to the snrface distribntion of the functional gronp as well as to lateral variations in the gronp environmental and conformation. Second-harmonic generation (SHG) microscopy has also been demonstrated for both spread monolayers and LB films of dye molecules [61,62]. The method images the molecular density and orientation field with optical resolution, and local qnantitative information can be extracted. 

FIG. 18 Scanning force microscopy images, (a) C60 transferred horizontally onto highly oriented pyrolytic graphite (HOPG) at 25 mN m. (b) 1 1 mixed film of C60 and arachidic acid transferred horizontally onto HOPG at 25 mN m. (Reproduced with permission from Ref. 235. Copyright 1996 American Chemical Society.)... 

Other noncontact AFM methods have also been used to study the structure of water films and droplets [27,28]. Each has its own merits and will not be discussed in detail here. Often, however, many noncontact methods involve an oscillation of the lever in or out of mechanical resonance, which brings the tip too close to the liquid surface to ensure a truly nonperturbative imaging, at least for low-viscosity liquids. A simple technique developed in 1994 in the authors laboratory not only solves most of these problems but in addition provides new information on surface properties. It has been named scanning polarization force microscopy (SPFM) [29-31]. SPFM not only provides the topographic stracture, but allows also the study of local dielectric properties and even molecular orientation of the liquid. The remainder of this paper is devoted to reviewing the use of SPFM for wetting studies. 

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