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Scanning electron microscopy by slow and Auger electrons
Hrnčiřík, Petr
The main goal of the work is comparison of signals in slow and Auger electrons in situ in scanning electron microscope. The project includes completion of the experimental device, accomplishment of simulations and computations of its properties and interpretation of the obtained image data.
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Secondary electron contrast of doped regions in semiconductor
Čižmár, Petr
The aim of the dissertation is study of multi-channel spectroscopy of electrons (secondary, both elastically and non-ellastically reflected as well as the Auger ones) in a scanning electron microscope with respect to the signal-to-noise ratio in detected signals. Another aim is to write software for electronic processing of an image of a specimen providing combined analytical and microscopic information. Verification of the methodology at an ultra-high vacuum microscope with slow electrons, which will be equipped with a parallel hyperbolic electrons analyzer in the scope of the project, is one of main goals of the experimental part.
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An ultrahigh vacuum scanning low energy electron microscope for surface studies
Müllerová, Ilona ; Frank, Luděk
In the course of recent six years, a complex device for examination of clean and well-defined surfaces with low energy electrons under ultrahigh vacuum conditions has been developed and put into operation. The apparatus is intended for exploration of novel image contrasts, available at landing energies of the scanning primary beam below 100 eV, under a residual pressure in the specimen vicinity in the order of 10.sup.-10./sup. mbar. The instrument consists of three vacuum chambers: the observation chamber, a chamber for in-situ preparations and the loading chamber of the air lock.
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Secondary electron contrast of dopped regions in semiconductor - a matter of surface treatment?
Frank, Luděk ; Müllerová, Ilona ; El-Gomati, M.
Direct observation of doped patterns in semiconductor, usually on cleavedsections through multilayers but recently also in plan views of patterneddoping of a technological layer, is acquiring high interest because of its straightforward application in the semiconductor technology. Plenty of experimental data has been collected [1-4] from conventional SEM observation and recently first results showed improved contrasts attainable with specimen immersed into electric field. Main features are the sign of contrast- the p-type regions are always brighter than the n-type ones, and the contrast grows toward lower energies.
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Ultrahigh vacuum scanning low energy electron microscope (UHV SLEEM) for surface studies
Müllerová, Ilona ; Frank, Luděk
The aim of project is to study clean and well-defined surfaces via interaction of electrons at energies from 0 to 25 keV with a high spatial resolution. During the period 1995-2001 we have built an Ultrahigh Vacuum Scanning Low Energy Electron Microscope for surface studies. The image resolution below 50 nm can be achieved at 10 eV. The residual pressure in the specimen vicinity is 10.sup.-10./sup. mbar. The paper briefly describes main parameters of the instrument.
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Examination of semiconductor structures with slow electrons
Frank, Luděk ; Müllerová, Ilona
Possibilities for visualization of the doped areas and variances in the local density of electron states are briefly reviewed. First examples are presented of utilizing very slow electrons in a cathode lens equipped SEM for this purpose. These include acquisition of the doping contrast via secondary electrons and observation of the local energy band structure by means of elastically backscattered electrons.
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Scanning low and very low energy electron microscopy
Müllerová, Ilona ; Frank, Luděk
The main aspects of the SEM performed in the low energy (below 5 keV) and very low energy (below 50 to 100 eV) ranges are briefly summarised. They include the necessity to vary the beam energy along the column, in order to suppress the energy dependence of the resolution, and to tune the compromise between the resolution and the field on the specimen surface. Applications under "normal" vacuum conditions are mentioned.
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