Sinossi
1. Why such an effort?.- The problem with the magnification.- The limitation of resolution.- Electron waves.- The role of magnification.- 2. What should we know about electron optics and the construction of an electron microscope.- The principle of multistage imaging.- Rotational-symmetric magnetic fields as electron lenses.- Lens aberrations.- Resolution limit considering the spherical aberration.- Electron gun.- "Richtstrahlwert" (brightness).- We construct an electron microscope.- Illumination system.- Imaging system.- Specimen stage.- Acquiring the images.- Vacuum system.- Miscellaneous.- We prepare electron-transparent samples.- What is the challenge?.- "Classical" methods.- Cutting, grinding, and ion milling.- Focused Ion Beam ("FIB") techniques.- 4. Let us start with practical microscopy.- What do we peripherally need?.- We put the specimen into the holder and insert it into the microscope.- We check the (alignment) state of the microscope.- Focussing the image - sharpness and contrast.- Contamination and sample damaging.- 5. Let us switch to electron diffraction.- Why diffraction reflexes?.- Crystal lattices and lattice planes.- Selected area and convergent beam electron diffraction.- What can we learn from selected area diffraction patterns?.- Radii in ring diagrams.- Rules for forbidden reflections.- Intensities of diffraction reflections.- Positions of diffraction reflections in point diagrams.- Indexing of diffraction reflections.- Kikuchi- and HOLZ-lines.- Amorphous samples.- 6. Why do we see any contrast in the images?.- Elastic scattering of electrons within the sample.- Mass thickness and diffraction contrast.- Brightfield and darkfield imaging.- Bending contours, dislocations, and semicoherent particles.- Thickness contours, stacking faults, and twins.- Moiré patterns.- Magnetic domains: Lorentz microscopy.- 7. We increase the magnification.- Imaging of atomic columns in crystals: Phase contrast.- Contrast transfer by the objective lens.- Wave-optical interpretation of the resolution limit.- Periodic distribution of brightness in pictures: Fourier analysis.- Mass thickness and phase contrast.- Contrast of amorphous samples.- Correction of astigmatism.- Measurement of the resolution limit.- Correction of spherical and chromatic aberration.- Interpretation of high resolution TEM images.- 8. Let us switch to scanning transmission electron microscopy.- What happens electron-optically?.- Resolution or: What is the smallest diameter of the electron probe?.- Contrast in the scanning transmission electron microscopic image.- Speciality: High angle annular darkfield detector (HAADF).- J. Thomas, T. Gemming: "Analytical TEM - an Introduction for Operators".- 9. Let us use the analytical possibilities.- Analytical signals by inelastic interaction.- Emission of X-rays.- Electron energy losses.- Energy dispersive spectroscopy of characteristic X-rays ("EDXS").- X-ray spectrometers and spectra.- Qualitative interpretation of X-ray spectra.- Quantifying X-ray spectra.- Line profiles and elemental mappings.- Electron energy loss spectroscopy ("EELS").- Electron energy spectrometer.- Low-loss und Core-loss regions of the spectra.- Qualitative elemental analysis.- Background and multiple scattering: Requirements to the sample.- Measurement of the specimen thickness.- Edge fine structure: Bonding analysis.- Quantifying energy loss spectra.- Energy filtered imaging.- Comparison between EDXS and EELS.- 10. Basics explained in more detail (with a bit more mathematics).- Diffraction at an edge (Huygens' principle).- Wave function for electrons.- Electron wavelength relativistically calculated.- Electron beam paths in rotational-symmetric magnetic fields.- Resolution limit considering spherical aberration.- Schottky effect.- Electrical potential in rotational-symmetric arrangements of electrodes.- Laue equations and reciprocal lattice, Ewald construction.- Kinematical model: Lattice factor and structure factor.- Debye scattering
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