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Study of the interaction of nanocomposite films with plasma
Steinhartová, Tereza ; Hanuš, Jan (advisor) ; Kousal, Jaroslav (referee)
The theoretical part deals with basic characteristics of low-temperature, low-pressure plasma. It describes the principles of preparation of nanocomposite films using this type of plasma and also the etching process in chemically active plasma. It further explains the basic principles of methods used to characterize our samples. The experimental part describes the process of optimalization of chemically active plasma ($O_2/Ar$) employed for etching of plasma polymer films. After finding suitable etching parameters several types of films were prepared. First, films of plasma polymer and then nanocomposite films composed of metal and plasma polymer. Afterwards the samples were treated in defined conditions of oxygen plasma. The aim was to study the physico-chemical properties of these films, especially their chemical composition using X-ray photoelectron spectroscopy, and wettability. Attention was given to the change of the water contact angle as a function of etching time and morphology of the pample. In case of oxygen etching ageing of the film was studied. By increasing of roughness superhydrophobic (SHF) film was prepared.
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XPS analysis of plasma polymers and nanocomposite films without breaking vacuum
Artemenko, Anna ; Biederman, Hynek (advisor) ; Čech, Vladimír (referee) ; Novák, Stanislav (referee)
Title: XPS analysis of plasma polymers and nanocomposite films without breaking vacuum Author: Anna Artemenko Institute: Charles University in Prague, Department of Macromolecular Physics Supervisor of the doctoral thesis: Prof. RNDr. Hynek Biederman, DrSc., Charles University in Prague, Department of Macromolecular Physics. Abstract: Plasma polymers and metal/ plasma polymer nanocomposites have been widely used for various biomedical proposes. Naturally, surface properties of the coatings such as high wettability, stability on the open air and in aqueous media, resistance towards different sterilization processes and cells adhesion are required for bioapplications. This thesis is mainly dedicated to the investigation of chemical composition of deposited coatings using XPS analysis. Nylon-like plasma polymer, PEO-like coatings, fluorocarbon plasma polymer (PTFE) films and Au/PEO-like, Ag/C:H, Al/C:H nanocomposites were chosen as the subject material. In addition, results of XPS measurements were used for the computer simulation for calculation of filling factor of metal/ plasma polymer nanocomposites. These results were in a good agreement with experimental data. Keywords: plasma polymer, nanocomposite, XPS analysis, bioapplication, simulation.
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Stability of plasma polymers under various conditions
Matoušek, Jindřich ; Biederman, Hynek (advisor) ; Čech, Vladimír (referee) ; Novák, Rudolf (referee)
Title: Stability of plasma polymers under various conditions. Author: Jindřich Matoušek Department/Institute: Department of Macromolecular Physics/Charles University in Prague Supervisor of the doctoral thesis: prof. RNDr. Hynek Biederman, DrSc., Department of Macromolecular Physics Abstract: The depositions of plasma polymer thin films were carried out using plasma polymerization depostition. The working gas mixture consisted of argon and monomer vapours. The source monomers used were n-hexane and terthiophene. The depositions of nanocomposite thin films Sn/pp n-hexane by means of magnetron sputtering in a working gas mixture of argon and n-hexane were done. The resulting thin films were characterized by XPS, FTIR, AFM, SEM, TEM, optical microscope and elipsometry. The influence of deposition parameters on the resulting thin film propertires was studied. The ageing of the thin films in humidity and distilled water was studied. The current-voltage characteristics of selected thin films were measured. Keywords: plasma polymer, nanocomposite, ageing.
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Nanoclusters coatings for biomedical applications
Divín, Radek ; Kylián, Ondřej (advisor) ; Hanuš, Jan (referee)
Title: Nanoclusters coatings for biomedical applications Author: Radek Divín Department: Department of Macromolecular Physics (110. 32-KMF) Supervisor: RNDr. Ondřej Kylián, Ph.D. Abstract: The copper nanocluster films were prepared with the aid of the gas cluster aggregation source based on the principle of material sputtering from the magnetron target to the relatively high pressure of the working gas (Ar). The nanocluster films prepared in this way were subsequently overlapped with the layer of plasma polymer deposited by RF magnetron sputtering from the nylon polymer target in the atmosphere of the working gas (Ar, 2 Pa). A repetition of this procedure enabled to prepare nanocomposite layers having a multilayer character. These layers were subsequently investigated with regard to their morphology, chemical composition, surface wettability and optical properties. The chemical composition of the surface layer formed by nanocomposite films was determined by the X-ray photoelectron spectroscopy (XPS). It turned out that the chemical surface composition of prepared nanocomposites was not markedly influenced by the presence of the Cu nanoclusters. The morphology of prepared films was studied by the scanning electron microscopy (SEM) and the atomic force microscopy (AFM), which showed that the resulting...
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Preparation of Nanocomposites TiOx /Plasma Polymer and Study of Their Properties
Drábik, Martin ; Biederman, Hynek (advisor) ; Čech, Vladimír (referee) ; Špatenka, Petr (referee)
Title: Preparation of Nanocomposites TiOx/Plasma Polymer and Study of Their Properties Author: Mgr. Martin Drábik Department: Department of Macromolecular Physics Supervisor: Prof. RNDr. Hynek Biederman, DrSc. Supervisor's e-mail address: bieder@kmf.troja.mff.cuni.cz Abstract: This thesis concerns a study of nanocomposite films TiOx/plasma polymer prepared by various deposition techniques using different organic precursors. Processes of deposition of the films were diagnosed in-situ by means of OES and measuring the deposition rate by QCM. Properties of the nanocomposite films were studied by various characterization techniques. Wettability of the films was described by means of the contact angle of water. Morphology of the nanocomposites was characterized by AFM, TEM and SEM. Elemental analysis and chemical composition of the films were studied by XPS, RBS, SIMS and FTIR. Crystal structure of TiO2 films was identified by XRD. Optical characterization of the prepared films was done by UV-Vis spectroscopy. Electrical properties of the samples were characterized by I-V and SPV measurements. In the end, 'wet' chemical processes were utilized for preparation of both TiO2 nanostructures and organic films for comparison with vacuum deposition techniques and plasma polymer composite films. Keywords: nanocomposite...
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Surface and Mechanical Properties of Thin Films
Pálesch, Erik ; Klapetek, Petr (referee) ; Skuhurov,, Andrey (referee) ; Čech, Vladimír (advisor)
The doctoral thesis deals with the study of morphology and mechanical properties of thin plasma polymer films based on tetravinylsilane monomer and its mixtures with oxygen and argon. Thin films were prepared by plasma-enhanced chemical vapour deposition on silicon and glass substrates. Atomic force microscopy was used for characterization of thin film surface and for depiction of composite interphase with functional interlayer. Mechanical properties of thin films, namely Young’s modulus and hardness, were studied by cyclic nanoindentation technique. Nanoindentation device was also used to carry out scratch test, which was helpful to describe adhesion of films to substrate. In this thesis the influence of deposition conditions on surface and mechanical properties of thin films prepared in continual and pulse wave on planar substrates is discussed. Also, the suitability of few atomic force microscopy techniques for depiction of composite interphase was reviewed.
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Study of Thin-Film Surfaces
Trivedi, Rutul Rajendra ; Fejfar, Antonín (referee) ; Klapetek, Petr (referee) ; Šikola, Tomáš (referee) ; Čech, Vladimír (advisor)
Disertační práce se zabývá studiem povrchových vlastností jedno a vícevrstvých filmů deponovaných z vinyltriethoxysilanových a tetravinylsilanových monomerů. Zabývá se také charakterizací adheze jednovrstvých filmů z tetravinylsilanu. Plazmaticky polymerizované tenké vrstvy byly připraveny na leštěných křemíkových substrátech pomocí plazmové depozice z plynné fáze za ustálených podmínek. Povrchové vlastnosti vrstev byly charakterizovány pomocí různých metod rastrovací sondové mikroskopie a nanoindentačních technik jako je konvenční a cyklická nanoindentace. Vrypový test byl použit pro charakterizaci vlastností adheze vrstev. Jednovrstvé filmy připravené za různých depozičních podmínek byly charakterizovány s ohledem na povrchové morfologie a mechanické vlastností (modul pružnosti, tvrdost). Výsledky morfologie povrchu, analýzy zrn, nanoindentace, analýzy konečných prvků a modulů mapování pomohly rozlišit hybridní charakter filmů, které byly deponovány při vyšších výkonech RF-výboje. Nový přístup byl použit v povrchové charakterizaci vícevrstvého filmu pomocí rastrovací sondové mikroskopie a nanoindentace. Adhezívní chování plazmaticky polymerizovaných vrstev různých mechanických vlastností a tloušťek bylo analyzováno pomocí normálních a laterálních síl, koeficientu tření, a snímků vrypů získaných pomocí mikroskopie atomárních sil.
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Plasmachemical processing of fibrous reinforcements for polymer composites
Knob, Antonín ; Lapčík, Ĺubomír (referee) ; Čech, Vladimír (advisor)
The diploma thesis is aimed at coating of glass fibers using tetravinylsilane as a monomer by Plasma-Enhanced Chemical Vapor Deposition (PECVD). The surface modified fibers were used as reinforcements for unsaturated polyester resin to form composites of controlled interphase. Chemical and mechanical properties of thin films were controled by the effective power. Determination of fiber-matrix adhesion and an influence of polymer-interface on mechanical properties of composites were characterized by Scanning Electron Microscopy (SEM) and microindentation technique using Interfacial Testing System (ITS) enabling to measure the interfacial shear strength.
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Adhesion characterization of thin plasma-polymer films
Pálesch, Erik ; Klapetek, Petr (referee) ; Čech, Vladimír (advisor)
The diploma thesis deals with characterization of adhesion of plasma polymer films deposited on silicon wafers. The samples included organosilicon thin films based on tetravinylsilane monomer prepared by plasma-enhanced chemical vapour deposition. Scratch test was used to characterize film adhesion employing nanoindentation measurements. Adhesion of plasma polymer films of different mechanical properties and film thickness was analyzed by normal and lateral forces, friction coefficient, and scratch images obtained by scanning probe microscope working in atomic force microscopy mode.
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Diagnostics of thin film barrier properties
Horák, Jakub ; Mazánková, Věra (referee) ; Přikryl, Radek (advisor)
This thesis is focused on characterization of the SiOx thin layers properties prepared by plasma enhanced chemical vapour deposition (PECVD). The layers were characterized with regard to its future possible use for the protection of the museum archives against the corrosion. Liquid hexamethyldisiloxane was used as a precursor. Polypropylene foils and silica wafers were used as substrates for thin film preparation. Metal sheets were chosen for corrosion tests. Methods such as permeation rate measurement (oxygen transmission rate - OTR), Fourier transformation infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), ellipsometry and simple corrosion tests of steel sheets coated and uncoated by SiOx thin layer were used for the layer properties characterization.
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