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Plasmachemical deposition and characterization of hexamethyldiloxane thin layers
Blahová, Lucie ; doc. Mgr. Vít Kudrle. Ph.D. (referee) ; Krčma, František (advisor)
Thin films have been used to modify surface properties of various materials for many years. Plasma Enhanced Chemical Vapor Deposition (PECVD) is one of the possible methods for their preparation and this technique is applied in this work as well. An organosilicone – hexamethyldisiloxane – is used as precursor. Thin films are created on the surface of the substrate using mixture of precursor and oxygen in radiofrequently excited capacitively coupled plasma. The aim of the thesis is to find the optimal deposition conditions for production of transparent thin layers with good barrier capabilities, low oxygen transmission rate especially. Thin film depositions were realized for different compositions of the deposition mixture in continuous and pulsed mode of plasma with varying supplied power and duty cycle values. The deposition process itself was monitored in situ by optical emission spectroscopy. Thin film coatings were analyzed to determine their physical chemical properties (infrared spectroscopy, surface energy) and barrier properties. Using optical emission spectroscopy, important particles were identified in the deposition plasma. Vibrational, rotational and electron temperatures were determined from relative intensities of chosen fragments. Composition of thin films was studied by infrared spectroscopy. The best results of oxygen transmission rate were achieved with layers prepared from deposition mixture with high oxygen content. It was possible to improve barrier properties by performing deposition in pulsed plasma mode with 20–30% duty cycle. In this diploma thesis, optimal deposition conditions of thin films from hexamethyldisiloxane with low oxygen transmission rate were determined. It is possible to use these results in practical applications, such as corrosion inhibitors for archaeological objects. Optionally, they can be used in various industry branches where it is desirable and feasible to prevent oxygen access to the material by deposition of barrier coatings.
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Plasma diagnostics during the organosilicone layers deposition
Jakobová, Martina ; Dvořák,, Pavel (referee) ; Krčma, František (advisor)
This Bachelor thesis deals with plasma diagnostics during deposition of thin organic-silicone layers. Hexamethyldisiloxane (HMDSO) was use as a precursor and emission spectroscopy of plasma was used as diagnostic method. Theoretical part describes plasma and its most important properties. Attention has been also paid to processes of plasma-chemical deposition of thin layers, their use and properties. Finally, principles of emission spectroscopy and calculation procedures of vibrational, rotational and electron temperatures in plasma are described. Deposition itself was realised both in pulse and continuous mode of RF discharge under decreased pressure of 60 Pa. Apart from deposition in pure HMDSO also depositions with HMDSO with addition of 10 and 25 % of oxygen were realised. Measurements were performed in wavelength interval from 320 to 780 nm. Individual lines of atomic hydrogen H-alpha and H-beta were identified in the obtained spectra, as well as molecular bands of CO transitions 0-0, 0-1, 0-2, 0-3 and the second positive nitrogen system transitions 0-0, 0-1. The spectral line of atomic O was identified if oxygen was added into the reaction gas mixture. The dependences of selected bands and lines intensities on the power supplied to plasma were observed. Electron temperature was determined from hydrogen atomic lines, and it was varied within the interval from 2700 to 5500 K in dependence on deposition conditions. It was impossible to determine vibrational and rotational temperatures, since the necessary molecular constants for the detected particles were not found. Based on the obtained results, it was possible to determine partly composition of plasma and to determine some of its properties. Results show that composition and supplied energy influence considerably plasma itself and that in future it will be necessary to investigate relation between these parameters and properties of created thin layers.
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Speciální technické řešení pro úpravu přírodních substrátů pomocí atmosférického plazmového výboje
ŠOFRONIČ, Tomáš
The thesis deals with the design and subsequent construction of a special hermetic box for the treatment of biological substrates with the help of plasma discharge Gliding Arc. In the theoretical part of the thesis there is a summary of the basic information concerning the design of hermetic box, plasma, hexamethyldisiloxane as a precursor and wood as a lignocellulosic substrate. The experimental part of the thesis is focused on pilot measurements in which specimens were treated plasma and hexamethyldisiloxane. Furthermore, the effect of the treatment on the hydrophobic of the surface was investigated with the drop method. With the help of SEM microscopy was investigated the effect of modification on surface morphology
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Preparation of ppHMDSO Thin Films in Capacitively Coupled RF Glow Discharges under Dusty Plasma Conditions
Homola, V. ; Buršíková, V. ; Kelar, L. ; Kelarová, Š. ; Stupavska, M. ; Peřina, Vratislav
The deposition of organosilicone thin films from mixture of hexamethyldisiloxane (HMDSO) and oxygen by using capacitively coupled R.F. glow discharges under dusty plasma conditions was investigated. High resolution topography and mechanical property maps of the prepared films were acquired by using atomic force microscopy techniques. The chemical bond and composition of the deposited films were analyzed by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The mechanical properties of the films were studied using quasistatic as well as dynamic nanoindentation tests and their surface free energies were evaluated by means of contact angle measuring technique using several testing liquids exhibiting various surface tensions. The thermal stability of the films was studied using thermal desorption spectroscopy. Neural network modelling was used to study the effect of plasma parameters on the hardness of ppHMDSO films
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Plasmachemical deposition and characterization of hexamethyldiloxane thin layers
Blahová, Lucie ; doc. Mgr. Vít Kudrle. Ph.D. (referee) ; Krčma, František (advisor)
Thin films have been used to modify surface properties of various materials for many years. Plasma Enhanced Chemical Vapor Deposition (PECVD) is one of the possible methods for their preparation and this technique is applied in this work as well. An organosilicone – hexamethyldisiloxane – is used as precursor. Thin films are created on the surface of the substrate using mixture of precursor and oxygen in radiofrequently excited capacitively coupled plasma. The aim of the thesis is to find the optimal deposition conditions for production of transparent thin layers with good barrier capabilities, low oxygen transmission rate especially. Thin film depositions were realized for different compositions of the deposition mixture in continuous and pulsed mode of plasma with varying supplied power and duty cycle values. The deposition process itself was monitored in situ by optical emission spectroscopy. Thin film coatings were analyzed to determine their physical chemical properties (infrared spectroscopy, surface energy) and barrier properties. Using optical emission spectroscopy, important particles were identified in the deposition plasma. Vibrational, rotational and electron temperatures were determined from relative intensities of chosen fragments. Composition of thin films was studied by infrared spectroscopy. The best results of oxygen transmission rate were achieved with layers prepared from deposition mixture with high oxygen content. It was possible to improve barrier properties by performing deposition in pulsed plasma mode with 20–30% duty cycle. In this diploma thesis, optimal deposition conditions of thin films from hexamethyldisiloxane with low oxygen transmission rate were determined. It is possible to use these results in practical applications, such as corrosion inhibitors for archaeological objects. Optionally, they can be used in various industry branches where it is desirable and feasible to prevent oxygen access to the material by deposition of barrier coatings.
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Plasma diagnostics during the organosilicone layers deposition
Jakobová, Martina ; Dvořák,, Pavel (referee) ; Krčma, František (advisor)
This Bachelor thesis deals with plasma diagnostics during deposition of thin organic-silicone layers. Hexamethyldisiloxane (HMDSO) was use as a precursor and emission spectroscopy of plasma was used as diagnostic method. Theoretical part describes plasma and its most important properties. Attention has been also paid to processes of plasma-chemical deposition of thin layers, their use and properties. Finally, principles of emission spectroscopy and calculation procedures of vibrational, rotational and electron temperatures in plasma are described. Deposition itself was realised both in pulse and continuous mode of RF discharge under decreased pressure of 60 Pa. Apart from deposition in pure HMDSO also depositions with HMDSO with addition of 10 and 25 % of oxygen were realised. Measurements were performed in wavelength interval from 320 to 780 nm. Individual lines of atomic hydrogen H-alpha and H-beta were identified in the obtained spectra, as well as molecular bands of CO transitions 0-0, 0-1, 0-2, 0-3 and the second positive nitrogen system transitions 0-0, 0-1. The spectral line of atomic O was identified if oxygen was added into the reaction gas mixture. The dependences of selected bands and lines intensities on the power supplied to plasma were observed. Electron temperature was determined from hydrogen atomic lines, and it was varied within the interval from 2700 to 5500 K in dependence on deposition conditions. It was impossible to determine vibrational and rotational temperatures, since the necessary molecular constants for the detected particles were not found. Based on the obtained results, it was possible to determine partly composition of plasma and to determine some of its properties. Results show that composition and supplied energy influence considerably plasma itself and that in future it will be necessary to investigate relation between these parameters and properties of created thin layers.
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Plasma modification of materials for medical purposes
MATĚJÍČEK, Jan
This diploma thesis deals with the ongoing research under the auspices of the Department of Applied Physics and Technics Faculty of Education, University of South Bohemia in České Budějovice, in which the author of the work was actively participated. The thesis is divided into theoretical and experimental part. The theoretical part contains information from natural polymers, especially cellulose, plasma technology and infrared spectrometry. The subject of the experimental part of the thesis is research that deals with the functionalization of cellulose using a microwave plasma discharge on the apparatus CX-22. In the present research was also conducted to process optimization of functionalization with the liquid precursor hexamethyldisiloxane (HMDSO).
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