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Development and Application of an UHV Equipment for Deposition of Thin Films (Atomic and Ion Systems)
Mach, Jindřich ; Čech, Vladimír (referee) ; Lencová, Bohumila (referee) ; Šikola, Tomáš (advisor)
In the thesis the development of two equipment for preparation of ultrathin films under ultrahign vacuum conditions (UHV) is discussed. Here, additionally to a brief description of theoretical principles, more details on the design of these units are given. In the first part the design of a thermal source of oxygen or hydrogen atomic beams is discussed. Further, a design and construction of an ion–atomic beam source for ion-beam assisted deposition of thin films is detailed. The source combines the principles of an efusion cell and electron-impact ion beam source generating ions of (30 – 100) eV energy. The source has been successfully applied for the growth of GaN on the Si(111) 7x7 substrate under room temperature.
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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 (
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Design of the atomic source producing carbon beams for deposition of graphene in UHV conditions
Horáček, Matěj ; Kolíbal, Miroslav (referee) ; Mach, Jindřich (advisor)
This bachelor's thesis deals with the design of the atomic source of carbon beams for deposition of graphene in UHV conditions. In the first part, problems on the growth of ultrathin layers, the theory of atomic beams and molecular beam epitaxy are described. The second part is aimed to graphene layers - especially the growth of graphene using molecular beam epitaxy. In the third part, the detection of carbon atomic beams is discussed. The practical part of this bachelor's thesis deals with the design and the construction of high-temperature atomic source of carbon. In the conclusion the obtained results are discussed.
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Optimization of the radiofrequency atomic source for deposition of GaN
Kern, Michal ; Wertheimer, Pavel (referee) ; Mach, Jindřich (advisor)
This thesis is focused on construction and optimization of radiofrequency atomic dissociation source of atomic nitrogen for depostion of GaN. The theoretical part deals with atomic sources, growth of ultrathin layers and the issue of radiofrequency circuits, with emphasis on their design using Smith chart. Methods for synthesis of GaN ultrathin layers and deposition are also discussed. In the experimental part, design and realization of various congurations of the impedance matching network is described. Using the impedance matching network a nitrogen plasma discharge was successfuly created and its spectrum was analysed. Afterwards, design and realization of a stepper motor control for the impedance matching network is described.
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Design and Construction of an Effusion Cell for Growth of Ultrathin Layers
Křápek, Ondřej ; Voborný, Stanislav (referee) ; Mach, Jindřich (advisor)
This Bachelor's work deals with the design, documentation and construction of effusion cell for deposition of ultrathin layers of various materials in conditions of ultrahigh vacuum. After fabrication and assemblage the effusion cell was placed to an ultrahigh vacuum chamber (p ~ 10-5 Pa) where the first testing deposition of a silver ultrathin film on Si (111) substrate was performed. This sample was studied by X-ray photoelectron spectroscopy and atomic force microscopy.
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