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Thermal Desorption Spectroscopy (TDS) and its Application for Research of Surface Processes
Potoček, Michal ; Čech, Vladimír (referee) ; Pavlík, Jaroslav (referee) ; Dub, Petr (advisor)
ermal desorption spectroscopy (TDS) is a common method for surface analysis of adsorbed molecules. In chapter 1 the work deals with the theoretical background of this method and shows the principles of a desorption process influenced by subsurface diffusion. Chapter 2 first shows application of TDS for detection of surface molecules and determination of binding energy.Experiments were mainly focused on ditermination of surface adsorbents and impurities on Si wafers. The second part of chapter 2 describes desorption of atoms of a Ga layer on Si surface and their subsurface diffusion. A Ga diffusion process was also observed by with secondary ion mass spectrometry (SIMS) and numerically simulated.
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Automatization of TDS data evaluation
Badin, Viktor ; Bábor, Petr (referee) ; Potoček, Michal (advisor)
Tato práce se zabývá automatizací vyhodnocování dat termální desorpční spektroskopie (TDS). Teoretická část pojednává o procesích adsorpce a desorpce atomů a molekul a teplotní závislosti desorpce. Součástí práce je také kvantitativní analýza signálu měřícího přístroje. Hlavním cílem praktické části bylo vytvoření počítačového programu na automatizaci vyhodnocování dat TDS. Popis programu a uživatelská příručka jsou také součástí práce. Proběhlo testování programu na předchozích měření a kinetické parametry desorpce byly zjištěny u několika vzorků.
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Study of gas molecule - surface interaction
Kettner, Miroslav ; Nehasil, Václav (advisor) ; Johánek, Viktor (referee)
Title: Study of gas molecule - surface interaction Author: Miroslav Kettner Department: Department of surface and plasma science Supervisor: doc. RNDr. Václav Nehasil, Dr., Department of surface and plasma science Abstract: In this work, we examined the suitability of rhodium deposited on a plasma sprayed substrate of titanium dioxide for catalysis reactions. With X-ray photoelectron spectroscopy method, the thermal stability of TiO2 prepared with plasma spray technology on aluminum plate was tested at first. Then, rhodium was evaporated on substrate and thermal stability of the whole system Rh/TiO2 was determined. Further methods of thermal desorption spectroscopy and molecular beam were used to study adsorption and desorption of CO and reaction of CO with oxygen. It was verified that the system Rh/TiO2 ceases to adsorbing CO after heating above 620 K, also the CO reaction with oxygen exhibits considerably lower intensity after heating above 620 K. After calibrating on rhodium plate, it was determined that the intensity of CO2 creation on Rh/TiO2 is four times lower than intensity on the rhodium plate. Unprompted adsorption and desorption passivation of the system, however, seems to be the most significant problem. Therefore, the system was assessed as unsuitable for further research. Keywords: Rh, TiO2,...
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Thermal desorption spectroscopy in prototype furnace for chemical vapor deposition
Průcha, Lukáš ; Daniel, Benjamin ; Piňos, Jakub ; Mikmeková, Eliška
Cleaning of the sample surfaces is crucial for scanning electron microscopy, especially for\nlow energy electron microscopy or for the deposition of thin layers, such as graphene,\nwhere surface has to be well prepared. In the best case, every unwanted particle should be\ncleaned from the sample surface for best low energy electron microscopy observation or thin\nfilm deposition. Unfortunately, the standard cleaning procedures can leave residues on the\nsample surface. This work is focused on thermal desorption spectroscopy (TDS). TDS is a method of observing desorbed molecules from a sample surface during the increase of\ntemperature of the sample. The aim of this study was to determine optimum conditions:\ntemperature and time, to achieve clean surfaces in the shortest time.
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Study of gas molecule - surface interaction
Kettner, Miroslav ; Nehasil, Václav (advisor) ; Johánek, Viktor (referee)
Title: Study of gas molecule - surface interaction Author: Miroslav Kettner Department: Department of surface and plasma science Supervisor: doc. RNDr. Václav Nehasil, Dr., Department of surface and plasma science Abstract: In this work, we examined the suitability of rhodium deposited on a plasma sprayed substrate of titanium dioxide for catalysis reactions. With X-ray photoelectron spectroscopy method, the thermal stability of TiO2 prepared with plasma spray technology on aluminum plate was tested at first. Then, rhodium was evaporated on substrate and thermal stability of the whole system Rh/TiO2 was determined. Further methods of thermal desorption spectroscopy and molecular beam were used to study adsorption and desorption of CO and reaction of CO with oxygen. It was verified that the system Rh/TiO2 ceases to adsorbing CO after heating above 620 K, also the CO reaction with oxygen exhibits considerably lower intensity after heating above 620 K. After calibrating on rhodium plate, it was determined that the intensity of CO2 creation on Rh/TiO2 is four times lower than intensity on the rhodium plate. Unprompted adsorption and desorption passivation of the system, however, seems to be the most significant problem. Therefore, the system was assessed as unsuitable for further research. Keywords: Rh, TiO2,...
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Thermal Desorption Spectroscopy (TDS) and its Application for Research of Surface Processes
Potoček, Michal ; Čech, Vladimír (referee) ; Pavlík, Jaroslav (referee) ; Dub, Petr (advisor)
ermal desorption spectroscopy (TDS) is a common method for surface analysis of adsorbed molecules. In chapter 1 the work deals with the theoretical background of this method and shows the principles of a desorption process influenced by subsurface diffusion. Chapter 2 first shows application of TDS for detection of surface molecules and determination of binding energy.Experiments were mainly focused on ditermination of surface adsorbents and impurities on Si wafers. The second part of chapter 2 describes desorption of atoms of a Ga layer on Si surface and their subsurface diffusion. A Ga diffusion process was also observed by with secondary ion mass spectrometry (SIMS) and numerically simulated.
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Automatization of TDS data evaluation
Badin, Viktor ; Bábor, Petr (referee) ; Potoček, Michal (advisor)
Tato práce se zabývá automatizací vyhodnocování dat termální desorpční spektroskopie (TDS). Teoretická část pojednává o procesích adsorpce a desorpce atomů a molekul a teplotní závislosti desorpce. Součástí práce je také kvantitativní analýza signálu měřícího přístroje. Hlavním cílem praktické části bylo vytvoření počítačového programu na automatizaci vyhodnocování dat TDS. Popis programu a uživatelská příručka jsou také součástí práce. Proběhlo testování programu na předchozích měření a kinetické parametry desorpce byly zjištěny u několika vzorků.
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