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Sample preparation and their measurement by EDS methods
Kostelník, Tomáš ; Jaššo, Kamil (referee) ; Čudek, Pavel (advisor)
This bachelor´s thesis is focused on preparation and analysis of samples by energy dispersive spectroscopy using scanning electron microscopy. In the theoretical the main differences between environmental scanning electron microscopy and scanning electron microscopy are described. There is also a description of basic knowledge regarding energy dispersive spectroscopy. The generation and detection of signals arising from the interaction of a beam of primary electrons with a sample is also explained, with emphasis on the description, generation and distribution of these signals. The experimental part is focused on sample preparation and analysis.
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Influence of working conditions on the results of X-ray analysis in the low vacuum scanning electron microscope
Hudzik, Martin ; Zimáková, Jana (referee) ; Čudek, Pavel (advisor)
Bachelor’s thesis deals with detection of characteristic X-Ray and energy dispersive spectroscopy in the environment of low vacuum scanning electron microscope. Describes the detection of X-Ray by silicon drifted detector and also describes the principles of qualitative and quantitative X-Ray analysis. The objective of this thesis is to perform energy dispersive spectroscopy of known elements under the optimal conditions and to monitor changes of parameters and results of the spectroscopy during the change of working conditions in low vacuum scanning electron microscope Vega3 XMU with Xflash 6|10 spectroscope.
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Scintillation Detector of Secondary Electrons for ESEM
Čudek, Pavel ; Špinka, Jiří (referee) ; Jirák, Josef (advisor)
The thesis deals with modifying and biulding of scintilation detector of secondary electrons for environmental scanning electron microscopy. It describes dilemma of environmental scanning electron microscopy, types of detectors and secondary electrons detection. The experimental part of this thesis focuses on the design and construction of new scintillation detector on the basis of simulations secondary electrons trajectories. Identifying the parameters, pressure dependencies and optimizations of electrode system of the detector realized.
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Ionization detector of secondary electrons for environmental scanning electron microscope
Dušek, Petr ; Zimáková, Jana (referee) ; Čudek, Pavel (advisor)
This thesis deals with problematics of a detection of secondary electrons by ionization detector for environmental scanning electron microscope. In this thesis is described the difference between scanning electron microscope and environmental scanning electron microscope. Further there is described emission and detection of the choosen signals that arise while primary electrons are interacting with a specimen in scanning electron microscope. A special emphasis is placed on a description, sorting and on the form of detection of secondary electrons. In thesis there is described principle of a function of ionization a scintilation detectors. Experimental part of thesis describes design of 3 different elctrode systems of a tabular ionization detector, which will be intended to be placed in environmental scanning electron microscope. Based on measuring with the detectors, with experimental design, there is chosen one with the highest quality of signal detection.
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Diagnostic of semiconductor materials by EBIC method
Davidová, Lenka ; Máca, Josef (referee) ; Čudek, Pavel (advisor)
Master´s thesis is focused on diagnostics of semiconductor materials by EBIC method (measuring of currents induced beam), determination of the lifetime of minority carriers, or their diffusion length. The theoretical part is aimed at the principle of scanning electron microscopy, the characteristic properties of the microscope and the signals generated by the interaction of the primary electron beam with the sample. The thesis describes a structure of semiconducting silicon, band models, types of lattice defects and doped of semiconductor structures. After that it is described the theory of calculation of the diffusion length of minority carriers in semiconductors of type N and P. The aim of the experiment part of the thesis is to measure the properties of the semiconductor structure by EBIC and determination of diffusion length and lifetime of minority charge carriers based on the measured data The aim of the experiment part of the thesis is to measure the properties of the semiconductor structure by EBIC and determination of diffusion length and lifetime of minority charge carriers on the basis of the measured data.
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Influence of working conditions on the signal level detected by LVSTD detector
Tylich, Ondřej ; Zimáková, Jana (referee) ; Čudek, Pavel (advisor)
This bachelor project includes information about function of low vacuum scanning electron microscope and describes it’s parts. It explains the difference between low vacuum and high vacuum scannig electron microscope. Contains informations about creation and detection of secondary electrons using scintillation detectors. It describes the calculation of signal to noise ratio and the method for obtaining the values of signal. Project is focused to determine the value of signal with a change in working conditions obtained by using Low Vacuum Secondary Electron Detector TESCAN (LVSTD). The aim is to determine the stability of the effect of working conditions on LVSTD.
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Influence of working conditions on results of EDS analysis in environmental SEM
Kaplenko, Oleksii ; Chladil, Ladislav (referee) ; Čudek, Pavel (advisor)
The bachelor thesis contains an operating principle of the environmental scanning electron microscope (ESEM), issue of detection of characteristic X-Ray by using an energy dispersive spectroscopy method. The work describes detection of X-rays through silicon drifted detector, and also the principle of qualitative and quantitative X-ray microanalysis. The aim of this work is to study the influence of working conditions in the scanning electron microscope VEGA3 XMU equipped with Xflash 6 | 10 spectroscope on the results of X-ray microanalysis and their evaluations.
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Measure the impact of wireless technologies on TEM
Prokop, Martin ; Čudek, Pavel (referee) ; Polsterová, Helena (advisor)
The purpose of this diploma thesis is to research and compare available wireless communication technologies (frequency, modulation type, transmission speed and consumption). Describe transmission electron microscopes theory and deduce the most sensitive microscope parts to high frequency distortion. Investigate effect of wireless technology on CE standards and come up with, perform and evaluate the influence measurement of chosen technologies on base parameters of transmission electron microscope.
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Method for signal level value evaluation in ESEM
Potoma, Jaroslav ; Jirák, Josef (referee) ; Čudek, Pavel (advisor)
This work deals with problematics of enviromental scanning electron microscopy and detection of signal electrons by ionization detector.The main goal of this work is to present a comparison of osciloscopical method for evaluation of signal level with method for evaluation of signal level from grayscale of common sample images. Evaluation of advantages and disadvantages of both methods.
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Determination of the chemical composition of a brass sample by X-ray fluorescence method
Tomanová, Michaela ; Čudek, Pavel (referee) ; Vaněk, Jiří (advisor)
The fluorescence spectroscopy method is used to distinguish components in gas, liquid, or solid samples. The study is based on the parameters of secondary radiation, which is emitted by each element and allows them to be identified. The distinction between each radiation is analogous to a fingerprint. Apart from quantitative and qualitative analyses, the method can be used to determine the thickness of metal layers and alloys. Laboratory analysis has a broader range of application than portable devices, which are also available. In the laboratory, two methods of measurement are available: wavelength dispersive fluorescence spectroscopy – WDXRF and energo dispersive fluorescence spectroscopy – EDXRF. A brass sample with lead additive was analyzed using EDXRF in the practical part of this diploma thesis. An X-ray apparatus from the Leybold company was employed for the analysis, which will be used for education of lower grades at the university. A measurement station and a laboratory assignment were developed as part of the thesis, the aim of which will be to determine the chemical composition of a brass sample using the X-ray fluorescence method.
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