|
|
Development of Atomic- and Ion Beam Sources
Šamořil, Tomáš ; Lencová, Bohumila (referee) ; Mach, Jindřich (advisor)
The objective of this master thesis was to provide the optimization of an ion-atom beam source for the improvement of its properties. The improvement of the parameters increases the efficiency of the source during the deposition of gallium nitride ultrathin films (GaN) being important in microeletronics and optoelectronics. After optimization, the depositions of GaN ultrathin films on Si(111) 7x7 at lower temperatures (
|
|
|
Surface Analysis by Photoelectrons – Computer Control of Experiments
Polčák, Josef ; Zemek, Josef (referee) ; Cháb, Vladimír (referee) ; Šikola, Tomáš (advisor)
Doctoral thesis is dealing with the methods for analysis of surfaces by photoelectrons being emitted by X-ray radiation. The methods are: X-ray Photoelectron Spectroscopy - XPS, Angle-resolved XPS - ARXPS and X-ray Photoelectron Diffraction - XPD. The work is especially focused on a method of ARXPS, which is used for the depth compositional analysis of sample surfaces. To obtain an information about the depth composition from the measured ARXPS spectra, a calculation software in the Matlab environment has been developed. The software has been tested both for simulated and real sample data. For an experimental implementation of these methods, a complete manipulation system has been developed. It ensures the transport of samples inside a vacuum apparatus and the experiment itself. The system is controlled mainly by a software and enables to run the experiments automatically.
|
|
|
Atomic structure of FeRh(001) surface
Ondračka, Václav ; Bábor, Petr (referee) ; Čechal, Jan (advisor)
Alloy of iron-rhodium, Fe50Rh50, shows a low-temperature metamagnetic phase transition between its antiferromagnetic and ferromagnetic state. A detailed description of this transition using the tools of surface analysis has not yet been done. This bachelor’s thesis focuses on preparation and characterisation of the alloy’s clean surface using X-ray photoemission spectroscopy and low-energy electron diffraction. A flat field correction and a diffraction measurement callibration is done using a sample with known crystal lattice in order to quantify the diffraction results.
|
|
| |
|
|
Organic materials for molecular quantum bits: deposition and chemical and morphological analysis
Komora, Mojmír ; Mach, Jindřich (referee) ; Čechal, Jan (advisor)
This bachelor thesis deals with an experimental preparation and analysis of ultra thin films of iron phtalocyanines on silicon substrates with goal to describe parameters of films prepared under different conditions, e.g deposition time or substrate temperature. Preparation of samples was done using MBE method under conditions of ultrahigh vacuum in vacuum chamber. Analysis of chemical composition and morfology of prepared films was done with methods of X-ray Photoelectron Spectroscopy, Scanning Electron Microscopy and Atomic Force Microscopy, respectively.
|
|
|
Preparation of graphene layers by various methods and characterization of their properties
Zahradníček, Radim ; Bartošík, Miroslav (referee) ; Lišková, Zuzana (advisor)
This bachelor's thesis deals with the production of graphene by different methods. Graphene was prepared by mechanical exfoliation and chemical methods. Graphene oxide (GO) was first prepared by modified Hummers method and disolved the solution in isopropyl alcohol. It was subsequently reduced by photoreduction, UV radiation and thermal reduction. Produced graphene samples were characterized using optical microscopy, electron microscopy, atomic force microscopy, Raman spectroscopy and X$-$ray photoelectron spectroscopy. Measurement results and evaluation of production quality of graphene are shown in this work.
|
|
|
Self-assembled layers based on silicon
Bábík, Adam ; Veselý, Michal (referee) ; Čech, Vladimír (advisor)
Thin film deposition, characterization and properties of self-assembled monolayers based on silicon were studied with emphasis on the SA monolayers deposited from vinyltriethoxysilane and vinyltrichlorsilane. The thesis is aimed at basic properties of the SA monolayer and explanation of its growth. Methods and techniques used for analysis of the monolayer were described as well. Contact angle measurements and an evaluation of the surface free energy are depicted in details. The deposited SA layers were observed with respect to their chemical composition and surface morphology by X-ray photoelectron spectroscopy (XPS), ellipsometry and atomic force microscopy (AFM).
|
|
|
Porting NetCOPE Platform to EDK
Palička, Jan ; Košař, Vlastimil (referee) ; Viktorin, Jan (advisor)
This bachelor's thesis deals with porting of NetCOPE to Xilinx Embedded Development Kit (EDK). Main task is to create annotation of NetCOPE hardware for using in EDK. Before implementation of annotation itself, it is necessary both to study FPGA technology, possibilities of FPGA progamming, NetCOPE platform and PSF for anotation of NetCOPE’s IP-core.
|
|
|
Preparation of elemental 2D materials
David, Jiří ; Čechal, Jan (referee) ; Kolíbal, Miroslav (advisor)
This thesis is focused on searching suitable experimental conditions for epitaxial growth of silicene, multilayer silicene and phosphorene, and their analysis by LEED and LEEM. Composition was analyzed by XPS. In the first part, a summary of literature research on properties and structure of these materials is presented. The second part describes experiments attemping to prepare these materials. Silicene was the only successfully-prepared material. It was imposible to reach suitable experimental conditions for multilayer silicene growth in the available experimetal setup. Deposition of phosphorus led only to formation of phosphorene precursor.
|
|
|
Oxidative passivation of metal powder
Kuna, Petr ; Solný, Tomáš (referee) ; Šoukal, František (advisor)
This thesis deals with the study of the effect of the oxide layer on the surface of metal powder on selected properties of fuel-oxidizer pyrotechnic system. Research includes finding optimal thickness of the oxide layer with using XPS and SEM methods, its conditions of formation and its influence on pressure-time curve and to resistance to ESD.
|
guest ::
