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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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Preparation and characterization of plasma activated water
Lemonová, Hana ; Klímová, Edita (referee) ; Krčma, František (advisor)
This bachelor thesis deals with suitable methods for plasma activated water preparation. The plasma activated water is a new way of the indirect plasma application for the treatment of biological materials like food or even for the direct application for therapeutic purposes. The theoretical part is focused on getting acquainted with plasma activated water and methods for its preparation, using various plasma systems. The detailed description of the plasma-liquid systems used during this thesis is given later. The selected physical chemical properties, namely conductivity, pH value and stability of hydrogen peroxide are presented in the results part. An important aspect of this work was to find suitable storage conditions for plasma activated water.
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Application of low temperature plasma jet systems for the deposition of thin films
Hubička, Zdeněk ; Kment, Štěpán ; Olejníček, Jiří ; Čada, Martin ; Straňák, V. ; Klusoň, J. ; Tichý, M. ; Klusoň, Petr
The low pressure DC pulsed or RF pulsed modulated hollow cathode plasma jets worked on the principle of the reactive sputtering of the hollow cathode usually in the gas mixture of Ar + O2 or N2. The DC pulsed power supplier was applied with combination of the RF source for the plasma jets generation. It was clearly demonstrated that properties of TiO2 and TiO2:N films significantly depended on the plasma parameters. First, the produced films were characterized with the aid of a number of methods (AFM, SEM, XRD, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), UV–vis spectrometry). Further, the films were judged in terms of their specific optical functionality to generate photocurrents upon being illuminated with spectrally well defined narrow light beams. The parameters of the chemically reactive plasma in the jets were determined using the time-resolved Langmuir probe system. The measurement of the ion energy distribution function was performed by means of the RFA.
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Pulsed plasma systems
Klusoň, Jan ; Kudrna, Pavel (advisor) ; Krčma, František (referee) ; Čada, Martin (referee)
The doctoral thesis deals with the experimental study of the low-temperature plasma designated for the preparation of thin films using the method of physical sputtering. It describes measurements which were realized on two types of devices - on the low-pressure plasma jet sputtering system and on the planar magnetron. The plasma diagnostics in the discharge excited in the pulse regime represent the main theme of the thesis. The discharge in the low-pressure plasma jet was studied by means of an electrostatic Langmuir probe, in the case of the planar magnetron, mass spectroscopy with energetic as well as time resolution was used. To understand the results achieved in the pulse generated plasma good knowledge of the basic continuous DC regime of the discharge excitation is essential. Therefore a considerable part of the thesis deals purely with the continuous DC discharge. In the case of the low- pressure plasma jet, the attention was focused also on the characteristic property of this plasma source, which is the flow from the jet.
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Studium parametrů plazmatu v plazmatické trysce
Štefániková, Estera ; Tichý, Milan (advisor) ; Klusoň, Jan (referee)
This thesis deals with the low-temperature plasma diagnostics by means of electrostatic Langmuir probe. The measurements were carried out on the experimental system of plasma jet which is very perspective mainly for the deposition of thin layers. Besides different resistant and industrial compelling surfaces there are also some layers with specific electrical or optical properties that cannot be prepared in other way. In order to control and reproduce such material depositions, the knowledge of plasma parameters is inevitable. The main contribution of this work lies in the measurement of vertical profiles of main plasma parameters (electron temperature, density and mean energy; the floating and plasma potential) in different pressure conditions.
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Technology of Production Frame of Case
Tvarůžek, Martin ; Kalivoda, Milan (referee) ; Osička, Karel (advisor)
The bachelor Thesis compares and evaluates the most advanced production technology of components frame of case. These cases are used for induction heating of material. The thesis compares technological features of the material division by means of plasma jet, water jet and laser. It also evaluates the using of the given technology from economic point of view.
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Volumetric Velocimetry and Accelerometry of Injected Particles in Thermal Plasma Jet
Šonský, Jiří
Measurements of the injected particles velocities and accelerations in the plasma jet are important for thermal plasma spraying technology improvement. Commonly used methods of optical diagnostic, such as particle image velocimetry (PIV) or particle tracking velocimetry and accelerometry (PTVA),are complicated due to strong optical self-emission of the plasma jet. We have developed 3-D variant of the PTVA, able to measure particle velocities and accelerations in hot core of the thermal plasma jet, as well as in surrouding areas, such as entrance of particle flow into the plasma jet.
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Numerical simulations of jet formation in laser-target interactions
Váchal, P. ; Liska, R. ; Kuchařík, M. ; Limpouch, J. ; Kmetík, Viliam
Cylindrical version of our two-dimensional Arbitrary Lagrangian Eulerian code PALE is applied for numerical studies of dense plasma jet formation from laser targets. Well collimated plasma expansion from a massive solid target irradiated by a single laser beam with a special profile is investigated. Particular interaction beam profile with intensity minimum in the beam centre is found to be responsible for jet formation during plasma expansion. A deep concave interaction beam profile at PALS is obtained from our simulation of the laser propagation in the amplifying chain and in the focusing system.
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