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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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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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Scintillation SE Detector with Controlled Gas Flow for VP SEM
Kozák, Josef ; Neděla, Vilém (referee) ; Jirák, Josef (advisor)
This master’s thesis deals with a design and optimization of an experimental scintillation secondary electron detector for the environmental scanning electron microscope and with a description of a detector operation principle. The experiment is founded on simulations of a gas flow in detector inner sections and on simulations of secondary electron trajectories in electrostatic fields of the detector. On the basis of the simulations, new solutions of the detector designs are proposed. For these designs, same simulations as previous are performed and designs that seem to be feasible for the secondary electron detection in environmental scanning electron microscope are selected.
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Scintillation SE detector for VP SEM
Račanský, David ; Čudek, Pavel (referee) ; Jirák, Josef (advisor)
First part of this thesis is a theoretical essay which deals with the basics of the variable pressure scanning electron microscope, includes detection of secondary electrons with a view to a scintillation detector. The first applied part of the thesis is focused on prediction, measuring and setting-up optional working parley in vacuum electrodes scintillation detector system, with a stress small diameter hole in screenings C1 and C2. Second applied part was verify a change of working distance between sample and detector in consequence to optional solution for another work.
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Scintillation SE detector fo environmental scanning electron microscope
Odehnal, Adam ; Čudek, Pavel (referee) ; Jirák, Josef (advisor)
This work contains theory about scanning electron microscopy. It describes construction, principle of operation and sinals generated by interactions between primary electron beam and specimen. Furthermore, it describes the most common method for detection of secondary electrons using scintillation detector. Next chapters are dealing with last development stage of scanning electron microscopy, which is environmental scanning electron microscopy. Experimental part is evaluating dependency of size of detected signal with scintillation detector on pressure of water vapor in specimen chamber. It also considers appropriate size of voltages enclosed on electrodes of the scintillation detector to optimize detection.
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Scintillation SE Detector for VP SEM
Kozelský, Adam ; Čudek, Pavel (referee) ; Jirák, Josef (advisor)
This work contains description of basic properties and principles of electron microscopy focused on scanning electron microscopy. It describes construction solutions of a microscope, interaction between electron beam and sample, generation of backscattered and secondary electrons. Next chapters are dealing with development of electron microscopy and environmental scanning electron microscopy. The experimental part of this thesis is focuses on the detection of secondary electrons with scintillation detector in environmental scanning electron microscope at higher pressure in the specimen chamber. Concretely is focused on optimization of collecting grid voltage and measurement of pressure dependences.
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Voltage contrast method in ESEM
Krňávek, Martin ; Čudek, Pavel (referee) ; Jirák, Josef (advisor)
This work contains theoretical description of basic features and principles of electron microscopy, with focus on environmental scanning electron microscopy. It describes function of the microscope, interactions that takes place after collision of electron pack with a sample, mainly it describes creation of back reflected electrons and secondary electrons and methods of voltage contrast. The practical part focus on voltage contrast issue by observing decomposition of electric potentials on surface of semiconductor devices and it establishes ideal working conditions for observing voltage contrast by scintillation detector of secondary electrons.
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