Scintilační detektor sekundárních elektronů pro ESEM
| Autor: | Čudek, Pavel |
|---|---|
| Jazyk: | čeština |
| Rok vydání: | 2016 |
| Předmět: |
zpětně odražené elektrony
detection of secondary electrons environmentální rastrovací elektronový mikroskop Rastrovací elektronový mikroskop primární elektrony secondary electrons environmental scanning electron microscope scintillation secondary electron detector sekundární elektrony scintilační detektor sekundárních elektronů primary electrons backscattered electrons poměr signál – šum. detected signal level signal noise ratio. Scanning electron microscope úroveň detekovaného signálu detekce sekundárních elektronů |
| Druh dokumentu: | Doctoral Thesis |
| Popis: | The thesis deals with the scintillation secondary electron detector for environmental scanning electron microscope, its design and construction. The starting point was numerical simulation of electrostatic fields and electron trajectories in the electrode system of the detector and simulation of pressure distribution and flow of gases in different parts of the detector. On the basis of modeling and simulation, construction changes of the detector were gradually implemented. Detection efficiency of each version of the detector was determined by the method described in the work. This method enables to evaluate signal level from the captured images of the specimen, quality of images was stated from signal to noise ratio. The thesis describes the whole process of the detector improvement from initial state, when the detector operated with lower efficiency in the pressure range from 300 to 900 Pa, to final version that enables usage of the detector in the range from vacuum up to 1000 Pa of water vapors in the specimen chamber of the microscope. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
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