Scanning reflection electron microscopy

Reflected High Energy Electron Diffraction Scanning Reflection Electron Microscopy... 

Surface Extended X-ray Absorption Fine Structure Surface Integrated Molecular Orbital/Molecular Mechanics Scanning Reflection Electron Microscopy Scanning Tunneling Microscope [or Microscopy]... 

For single crystal substrates which are not in the form of thin films, the techniques of transmission microscopy and nanodiffraction can not be used. For such cases, the techniques of reflection electron microscopy (REM) or its scanning variant (SREM) and reflection high energy electron diffraction (RHEED), in the selected area or convergent beam modes, may be applied (18). 

Figure 13.22. Reflection electron microscopy (REM) is an old technique that was revived in the 1980s but is still not widely used. The sample is essentially bulk material with just one surface viewed. The electrons are diffracted off the surface as in RHEED (the diffraction pattern looks just like any other RHEED pattern), and are then imaged by the TEM in the usual way. The resolution is about 0.7 nm and chemical analysis can be considered as shown by the AEGai (As/GaAs superiattice in this image square millimeters of surface can be viewed just by scanning the sample. Notice the foreshortening.

A. J. Bevolo. Scanning Electron Microscopy. 1985, vol. 4, p. 1449. (Scanning Electron Microscopy, Inc. Elk Grove Village, IL) Thorough exposition of the principles and applications of reflected electron energy-loss microscopy (REELM) as well as a comparison to other techniques, such as SAM, EDS and SEM. 

The interface properties can usually be independently measured by a number of spectroscopic and surface analysis techniques such as secondary ion mass spectroscopy (SIMS), X-ray photoelectron spectroscopy (XPS), specular neutron reflection (SNR), forward recoil spectroscopy (FRES), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), infrared (IR) and several other methods. Theoretical and computer simulation methods can also be used to evaluate H t). Thus, we assume for each interface that we have the ability to measure H t) at different times and that the function is well defined in terms of microscopic properties. 

Further structural information is available from physical methods of surface analysis such as scanning electron microscopy (SEM), X-ray photoelectron or Auger electron spectroscopy (XPS), or secondary-ion mass spectrometry (SIMS), and transmission or reflectance IR and UV/VIS spectroscopy. The application of both electroanalytical and surface spectroscopic methods has been thoroughly reviewed and appropriate methods are given in most of the references of this chapter. 

A number of techniques have been employed that are capable of giving information about amorphous phases. These include infrared spectroscopy, especially the use of the attenuated total reflection (ATR) or Fourier transform (FT) techniques. They also include electron probe microanalysis, scanning electron microscopy, and nuclear magnetic resonance (NMR) spectroscopy. Nor are wet chemical methods to be neglected for they, too, form part of the armoury of methods that have been used to elucidate the chemistry and microstructure of these materials. 

STM, X-ray reflectivity, and AFM are excellent in situ techniques for studying surface topography and morphology. Scanning electron microscopy is a useful ex situ technique. 

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