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Probe methods for diagnostics of plasmatic systems for deposition of thin films
Zanáška, Michal ; Tichý, Milan (advisor) ; Dvořák, Pavel (referee) ; Straňák, Vítězslav (referee)
The doctoral thesis deals with an experimental study of several diagnostic techniques intended for plasma diagnostics and diagnostics of thin films during reactive sputter deposition. A relatively novel probe diagnostic technique called Floating harmonic probe for measurement of the ion density and electron tem- perature in technological low-temperature plasma is studied. A Langmuir probe is commonly used, however, its application in conditions where non-conducting films are being deposited can be problematic or unreliable. The floating harmonic probe measurement technique deals with this inherent problem of the Langmuir probe. The Floating harmonic probe results are compared to those obtained by a classical Langmuir probe in non-reactive DC continuously driven discharge, and its applicability in reactive regime during deposition of iron oxide thin films is proved. The work deals also with a modification of the Floating harmonic probe called Phase Delay Harmonic Analysis Method which is intended for diagnostics of pulsed driven discharges. The second part of the thesis is devoted to a new proposed method for in-situ diagnostics of thin films. This method monitors the capacitance and resistance of a thin film during deposition up to the frequencies in the kHz range. This new method could be used for...
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Deposition of Nanocomposite Thin Films
Kratochvíl, Jiří ; Kylián, Ondřej (advisor) ; Straňák, Vítězslav (referee)
Nanocomposite thin films can find application in photovoltaics, optics, fabrication of sensors, or in biomedicine. This work investigates fabrication and characterization of thin metal-plasma polymer nanocomposite films which have direct application because of their unique optical properties (e.g. SERS - Surface-Enhanced Raman Spectroscopy) or antibacterial effects (biomedicine). We fabricated metal nanoparticles either by magnetron sputtering (island growth) or by means of gas aggregation source of nanoparticles, thereby we got nanoparticles with very different morphologies. We used silver as a material for nanoparticles because of its antibacterial effects. We incorporated these nanoparticles into sputtered Nylon and sputtered PTFE (polytetrafluoroethylene) plasma polymer matrix. These two polymers have very different chemical structure and related different surface energy. First, we compared growth of nanoparticles on substrates of sputtered Nylon and PTFE. Then we compared properties of sandwich nanocomposites polymer-Ag-polymer for both types of nanoparticles and for both matrix materials. We characterized produced thin films especially with respect to their stability in water (antibacterial films), thermal stability (sterilization by heating) and stability on the open air (storage). Finally, the tests...
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Ultrathin films deposited by means of magnetron sputtering and their characterization
Petr, Martin ; Kylián, Ondřej (advisor) ; Straňák, Vítězslav (referee) ; Tichý, Milan (referee)
Presented work is focused on the deposition and characterization of thin and ultrathin plasma polymer films, then also on the preparation of nanocomposites metal/plasma polymer. The characterization of plasma polymer films was partly done in-situ without exposing the samples to the atmosphere. The thickness of prepared films was measured by spectral ellipsometry, the chemical composition was measured by XPS. The morphology and optical properties of deposited films were measured ex-situ. It is shown that during the initial stages of growth the properties of plasma polymer films depend on their thickness and also on the material of the substrate. Many interesting applications were explored for prepared nanocomposites metal/plasma polymer. They can be used as superhydrophobic coatings, gradient coatings, substrates for Raman spectroscopy or as antibacterial coatings. Moreover, special optical properties of prepared nanocomposites were studied in detail. Presented work has an experimental character.
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Structuring of plasma polymers: new methods for fabrication of nano-architectured thin films
Nikitin, Daniil ; Shukurov, Andrey (advisor) ; Novák, Stanislav (referee) ; Straňák, Vítězslav (referee)
Title: Structuring of plasma polymers: new methods for fabrication of nano-architectured thin films Author: Daniil Nikitin Department / Institute: Department of Macromolecular Physics/Charles University Supervisor of the doctoral thesis: Doc. Ing. Andrey Shukurov, PhD, Department of Macromolecular Physics/Charles University Abstract: The PhD thesis aims at the investigation of nanostructures based on plasma polymers. The main attention is paid to the combination of a gas aggregation cluster source with plasma-assisted vapor phase deposition for the fabrication of metal-polymer nanocomposites with bactericidal potential. Copper nanoparticles were incorporated into a biocompatible matrix of plasma polymerized poly(ethylene oxide) (ppPEO). The efficiency of such nanocomposite against multi-drug resistant bacteria was demonstrated. It was found that the segmental dynamics of the plasma polymer significantly changed in the presence of nanoparticles as revealed by the measurements of the dynamic glass transition temperature. The nanoscale confinement crucially influences the non-fouling properties of poly(ethylene oxide). A separate chapter is dedicated to the examination of the nanoparticle formation, growth and transport inside the source. Copper and silver nanoparticles were detected in situ in the gas phase...
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Structuring of plasma polymers: new methods for fabrication of nano-architectured thin films
Nikitin, Daniil ; Shukurov, Andrey (advisor) ; Novák, Stanislav (referee) ; Straňák, Vítězslav (referee)
Title: Structuring of plasma polymers: new methods for fabrication of nano-architectured thin films Author: Daniil Nikitin Department / Institute: Department of Macromolecular Physics/Charles University Supervisor of the doctoral thesis: Doc. Ing. Andrey Shukurov, PhD, Department of Macromolecular Physics/Charles University Abstract: The PhD thesis aims at the investigation of nanostructures based on plasma polymers. The main attention is paid to the combination of a gas aggregation cluster source with plasma-assisted vapor phase deposition for the fabrication of metal-polymer nanocomposites with bactericidal potential. Copper nanoparticles were incorporated into a biocompatible matrix of plasma polymerized poly(ethylene oxide) (ppPEO). The efficiency of such nanocomposite against multi-drug resistant bacteria was demonstrated. It was found that the segmental dynamics of the plasma polymer significantly changed in the presence of nanoparticles as revealed by the measurements of the dynamic glass transition temperature. The nanoscale confinement crucially influences the non-fouling properties of poly(ethylene oxide). A separate chapter is dedicated to the examination of the nanoparticle formation, growth and transport inside the source. Copper and silver nanoparticles were detected in situ in the gas phase...
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Probe methods for diagnostics of plasmatic systems for deposition of thin films
Zanáška, Michal ; Tichý, Milan (advisor) ; Dvořák, Pavel (referee) ; Straňák, Vítězslav (referee)
The doctoral thesis deals with an experimental study of several diagnostic techniques intended for plasma diagnostics and diagnostics of thin films during reactive sputter deposition. A relatively novel probe diagnostic technique called Floating harmonic probe for measurement of the ion density and electron tem- perature in technological low-temperature plasma is studied. A Langmuir probe is commonly used, however, its application in conditions where non-conducting films are being deposited can be problematic or unreliable. The floating harmonic probe measurement technique deals with this inherent problem of the Langmuir probe. The Floating harmonic probe results are compared to those obtained by a classical Langmuir probe in non-reactive DC continuously driven discharge, and its applicability in reactive regime during deposition of iron oxide thin films is proved. The work deals also with a modification of the Floating harmonic probe called Phase Delay Harmonic Analysis Method which is intended for diagnostics of pulsed driven discharges. The second part of the thesis is devoted to a new proposed method for in-situ diagnostics of thin films. This method monitors the capacitance and resistance of a thin film during deposition up to the frequencies in the kHz range. This new method could be used for...
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Deposition of Nanocomposite Thin Films
Kratochvíl, Jiří ; Kylián, Ondřej (advisor) ; Straňák, Vítězslav (referee)
Nanocomposite thin films can find application in photovoltaics, optics, fabrication of sensors, or in biomedicine. This work investigates fabrication and characterization of thin metal-plasma polymer nanocomposite films which have direct application because of their unique optical properties (e.g. SERS - Surface-Enhanced Raman Spectroscopy) or antibacterial effects (biomedicine). We fabricated metal nanoparticles either by magnetron sputtering (island growth) or by means of gas aggregation source of nanoparticles, thereby we got nanoparticles with very different morphologies. We used silver as a material for nanoparticles because of its antibacterial effects. We incorporated these nanoparticles into sputtered Nylon and sputtered PTFE (polytetrafluoroethylene) plasma polymer matrix. These two polymers have very different chemical structure and related different surface energy. First, we compared growth of nanoparticles on substrates of sputtered Nylon and PTFE. Then we compared properties of sandwich nanocomposites polymer-Ag-polymer for both types of nanoparticles and for both matrix materials. We characterized produced thin films especially with respect to their stability in water (antibacterial films), thermal stability (sterilization by heating) and stability on the open air (storage). Finally, the tests...
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The investigation of low pressure HCPJ system for Ti02 film deposition
Perekrestov, Roman ; Kudrna, Pavel (advisor) ; Klusoň, Jan (referee) ; Straňák, Vítězslav (referee)
Title: The investigation of low pressure HCPJ system for TiO2 film deposition Author: Mgr. Roman Perekrestov Department / Institute: Department of Surface and Plasma Science Supervisor of the doctoral thesis: doc. Mgr. Pavel Kudrna, Dr. Abstract: Plasma sources are widely used for deposition of thin films for both commercial solutions as well as for research purposes. In particular, information about plasma parameters in such systems is of a great importance not only to ensure reproducibility, but also for the targeted influence on properties of deposited thin films. The aim of the dissertation was the study of plasma parameters with respect to the growth and properties of thin films deposited by means of HCPJ sputtering system. The investigated plasma system was plasma jet powered in DC mode. The diagnostics of the discharge was carried out by means of a cylindrical Langmuir probe, quadrupole mass and optical spectrometer. Neutral gas temperature in discharge was measured by an optic-fibre thermometer. The growth of nanoparticles in a gas phase was studied using scattering of laser beam light. For the diagnostics of Ti/TiO2 thin films were used XPS, SEM, AFM, TEM, XRD and EDX methods. The photovoltaic performance of TiO2 thin films was tasted in dye-sensitized solar cells. Keywords: plasma jet, Langmuir...
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Ultrathin films deposited by means of magnetron sputtering and their characterization
Petr, Martin ; Kylián, Ondřej (advisor) ; Straňák, Vítězslav (referee) ; Tichý, Milan (referee)
Presented work is focused on the deposition and characterization of thin and ultrathin plasma polymer films, then also on the preparation of nanocomposites metal/plasma polymer. The characterization of plasma polymer films was partly done in-situ without exposing the samples to the atmosphere. The thickness of prepared films was measured by spectral ellipsometry, the chemical composition was measured by XPS. The morphology and optical properties of deposited films were measured ex-situ. It is shown that during the initial stages of growth the properties of plasma polymer films depend on their thickness and also on the material of the substrate. Many interesting applications were explored for prepared nanocomposites metal/plasma polymer. They can be used as superhydrophobic coatings, gradient coatings, substrates for Raman spectroscopy or as antibacterial coatings. Moreover, special optical properties of prepared nanocomposites were studied in detail. Presented work has an experimental character.
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