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Surface and mechanical properties of a-CSi:H and a-CSiO:H films
Plichta, Tomáš ; Shukurov, Andrey (referee) ; Klapetek, Petr (referee) ; Čech, Vladimír (advisor)
The dissertation thesis deals with the preparation and characterisation of a-CSi:H and a CSiO:H thin films prepared using the process of plasma enhanced chemical vapour deposition (PECVD). Tetravinylsilane (TVS) and its mixtures with argon and oxygen were used to deposit films on both planar substrates and fibre bundles. Main characterisation techniques were employed to study the topography of films, namely atomic force microscopy (AFM). Their mechanical properties were studied through nanoindentation; the nanoscratch test was used to assess the film adhesion to the substrate. Other analysed properties were internal stress and friction coefficient. The particular attention was paid to the work of adhesion and its determination. This knowledge was further applied to the preparation of surface treatments of glass fibres and, subsequently, polymer composites. Those were tested using the push-out test and the short beam shear test. Based on the results, the effects of deposition conditions and the relationships between the studied properties and quantities were determined.
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Structure and Properties of Coatings Produced by PVD Technology
Doubrava, Marek ; Horynová, Miroslava (referee) ; Čelko, Ladislav (advisor)
The submitted work is focused on study of 3rd generation DLC films produced by Platit a.s. company. Thin films are deposited utilizing filtered cathodic vacuum arc process (FCVA). The main goal of thesis was to find out the influence on film properties, caused by change of the substrate holders with different heat dissipation. The change of the substrate holders is motivated purely by economical effort to increase productivity of the deposition process. Teoretical part of the thesis is about the principles of PVD deposition process, characterization of the thin films, DLC thin films and materials used for cutting tools. Experimental part includes description of devices used for specimens analyses, including also the description of measuring process and used conditions. Acquiered results, not only the thin film thickness, adhesion or amount of sp^3 bonds, match with expected results.
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THIN LUBRICANT FILMS STUDY USING SPECTROSCOPIC REFLECTOMETRY
Čudek, Vladimír ; Dzimko, Marián (referee) ; Navrátil, Karel (referee) ; Dobeš, Petr (referee) ; Křupka, Ivan (advisor)
ectroscopic reflectometry is measurement technique that enables the study of the thickness and refractive index of thin layers. This thesis deals with its use for the study of lubrication films within EHD contact and verifies a new approach suggested in recent publications. It is focused on the development of an optical arrangement and mathematical model for the lubrication film thickness measurement within the entire EHD contact. This technique brings the possibility to study the pressure distribution within the contact area through the evaluation of changes in lubricant refractive index.
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Thin Film Electrodes for Electrochromic Devices
Macalík, Michal ; Kadlec, Jaromír (referee) ; Nováková,, Sabina (referee) ; Sedlaříková, Marie (advisor)
The work deals with the deposition of layers for electrochromic device with different methods. Transparent electrically conductive layer of SnO2 was deposited by pyrolytic decomposition of peroxostannate solution. Hydrogen peroxide in starting solution contributes to the oxidation process of growth layers and to increase the electrical conductivity. Active electrochromic layer of WO3 was electrolytic deposited from the peroxotungstic acid solution. Optimal deposition time and the optimal annealing temperature of deposited layers were found. Passive electrochromic layer of V2O5 was deposited using dip-coating method from peroxovanadate solution. A contribution of solution diluted with distilled water was investigated. Found results were used to construct complete electrochromic device with polymer gel electrolyte.
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Creating themes thin-film methods
Ondráček, Michal ; Šimonová, Lucie (referee) ; Šubarda, Jiří (advisor)
The master’s thesis deals with the theory of thin film technology, especially creating these layers. The work includes the distribution of vacuum deposition techniques for physical (PVD) and chemical (CVD). The main aim is to create a theme in different ways of implementation by using magnetron sputtering device, and these motives evaluated in terms of the quality of sputtering.
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Effect of ion beam irradiation and annealing on magnetic properties of FeRh nanostructures
Zadorozhnii, Oleksii ; Turčan, Igor (referee) ; Staňo, Michal (advisor)
Fazový přechod prvního řádu z antiferomagnetického do feromagnetického stavu v Fe50Rh50 z něj činí vhodný materiál pro nové generace spinových elektronických zařízení s nízkou spotřebou. Tato práce se zabývá způsoby, jak lze teplotu fázového přechodu železo-rhodia (FeRh) lokálně ovlivnit pomocí fokusovaneho iontového svazku (FIB) a žíhání. FIB byl zvolen vzhledem k tomu, že slitina FeRh vykazuje magnetickou citlivost na stupeň jejího chemického uspořádání, což je charakteristické pro všechny slitiny feromagnetických a neferomagnetických kovů. Tepelné žíhaní umožňuje obnovení krystalografického uspořádání, a uvolnění mřižkových defektů a dislokací. Magnetické vzory byly vyrobeny za použití FIB na bázi galia a žíhány ve vakuu. Topografie a magnetické chování těchto iontově ozářených vzorů byly zkoumány pomocí mikroskopie atomárních a magnetických sil při různých teplotách, a ukázaly jasnou závislost mezi dávkou iontového záření a magnetickou odezvou ve stavu před a po žíhání.
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Deposited layers based on lead and cobalt for Li-ion batteries
Dorotík, David ; Libich, Jiří (referee) ; Máca, Josef (advisor)
The diploma thesis deals with the principles of operation of lithium ion batteries and their properties when using deposited thin films. The thesis is mainly focused on the formation of thin films using the electrolytic method and subsequently testing the properties of the thin film in an electrochemical cell. The test criteria are mainly the value of the capacity of the prepared electrode and the impact of cycling on the electrode layer itself, where the deposited layer is assessed before cycling and after cycling on an SEM microscope..
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Characterisation of dielectric films on a silicon wafer
Fillner, Patrik ; Boušek, Jaroslav (referee) ; Hubálek, Jaromír (advisor)
This bachelor thesis focuses on thin oxide based dielectric layers on silicon wafer. Main effort is for characterization of properties of samples. This technology can be used for manufacturing capacitors on silicon chips. Samples are based on planar oxide layers made with thin film technology on single silicon wafers coated with electrodes deposited by evaporation or by sputtering.
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Photocatalytic activity of hybrid titanium dioxide layers treated by plasma
Koukolová, Anna ; Králová, Marcela (referee) ; Veselý, Michal (advisor)
The bachelor thesis deals with photocatalytic activity of thin layer of titanium dioxide deposited onto PET flexible foil treated by plasma. Photocatalytic activity is measured by two different methods, degradation of dye Acid Orange 7 and benzoic acid. Possible model compounds for evaluation of photocatalytic activity as well as deposition techniques for preparing thin layers of photocatalyst were discuss in the theoretical part. Changes of photocatalytic activity were found insignificant with plasma treatment. Evaluation used Acid Orange 7 is suitable. Unlike method with benzoic acid was discovered inappropriate for measuring of photocatalytic activity for photocatalyst deposited onto PET foil.
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SiO2 etching by Si deposition
Pokorný, David ; Bábor, Petr (referee) ; Polčák, Josef (advisor)
This bachelor thesis deals with one of the most interesting reactions taking place in the solid phase in UHV conditions and that is decomposition of SiO2 according to the equation Si + SiO2 = 2SiO. It was used the previously untested procedure - providing Si atoms not from substrate, but by direct deposition on the surface of the oxide. As a source of silicon atoms was used effusion cell. Deposition of silicon on SiO2 substrate was used at room temperature and at elevated temperature to clarify the principle of this reaction. The activation energy and temperature dependence of the reaction rate was determined. It was also verified the possibility of etching SiO2 by Si deposition in UHV conditions. The prepared samples were examined by x-ray photoelectron spectroscopy and atomic force microscopy.
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