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Prospects of the scanning low energy electron microscopy in materials science
Mikmeková, Šárka ; Hovorka, Miloš ; Konvalina, Ivo ; Müllerová, Ilona ; Frank, Luděk
The use of the scanning low energy electron microscopy (SLEEM) has been slowly making its way into the field of materials science, hampered not by limitations in the technique but rather by the relative scarcity of these instruments in research institutes and laboratories. Various techniques exist which are capable of studying the material microstructure, with the scanning electron microscopy (SEM), (scanning) transmission microscopy ((S)TEM) and focused ion beam (FIB) microscopy being perhaps the most known. A specific way to visualizing the microstructure of materials at high spatial resolution, to achieve a high contrast between grains in polycrystals and very fast data acquisition is to use the cathode lens (CL) mode in SEM. The CL mode in the SEM enables us to detect slow but not only slow, high angle scattered electrons that carry mainly crystallographic contrast based on the electron channeling, mostly in the Mott scattering angular range.
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Imaging of dopants under presence of surface ad-layers
Mika, Filip ; Hovorka, Miloš ; Frank, Luděk
Scanning electron microscopy is widely used for imaging of semiconductor structures. Image contrast between differently doped areas is observable in the secondary electron emission. Quantitative relation exists between the image contrast and the dopant concentration. However, further examination has shown the dopant contrast level of low reproducibility and dependent on additional factors like the primary electron dose, varying energy and angular distributions of the SE emission and also presence of ad-layers on the semiconductor surface.
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Scanning electron microscopy with low energy electrons
Mika, Filip
A method of scanning electron microscopy (SEM) of nonconductive specimens, based on measurement and utilisation of the critical energy of electron impact, is described in detail together with examples of its application. The critical energy, at which the total electron yield curve crosses the unit level, is estimated on the base of measurement of the time development in the image signal from beginning of irradiation. The method is programmed and implemented as a module to the controlling software of the micropscope type VEGA, where it secures fast search for the critical energy value.
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Scanning electron microscopy with low energy electrons
Mika, Filip
A method of scanning electron microscopy (SEM) of nonconductive specimens, based on measurement and utilisation of the critical energy of electron impact, is described in detail together with examples of its applications. The critical energy, at which the total electron yield curve crosses the unit level, is estimated on the base of measurement of the time development in the image signal from beginning of irradiation. The method is programmed and implemented as a module to the controlling software of the microscope type VEGA, where it secures fast search for the critical energy value.
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