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Optimization of the Colutron Ion Source
Horký, Michal ; Mach, Jindřich (referee) ; Voborný, Stanislav (advisor)
This bachelor’s thesis concerns with design and assembly of Colutron ion source which produces beam of nitrogen ions with energy from tens to thousand eV. Production of ions and the principle of Colutron ion source is described in the first part. The second part of the thesis is related to the modification and assembly of commercial Colutron ion source. Finally the parameters of the ion beam have been measured for different extraction electrodes and operating parameters in testing apparatus.
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Studies of molecular beams of organic materials
Maniš, Jaroslav ; Průša, Stanislav (referee) ; Mach, Jindřich (advisor)
This bachelor's thesis deals with assembling of low-temperature efussion cell which is suitable for deposition of organic materials. The calibration of operating temperature of effusion cell is performed. Depositions of organic semiconductor material are realized. Morphology of surface of thin film is studied in AFM and SEM microscope. In the paper background research on the utilization of organic materials in semiconductor industry is presented.
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Design, Fabrication and Testing of Environmental Chamber for Atomic Force Microscope and for Electronic Measurements of Nanosensors
Cahlík, Aleš ; Mach, Jindřich (referee) ; Bartošík, Miroslav (advisor)
This thesis deals with the concept of the chamber for atomic force microscope device NTegra Prima or alternatively for stand-alone measurements of nanosensors. The chamber will be used for defined modification of ambient conditions in space around measured sample. In first part, the theoretical principles of influence of ambient conditions on AFM methods are discussed. In the second chapter, the principles of graphene sensors measurements are showed. Further the reasons and requirements for designing this chamber are introduced. Main part deals with description of design. At the end the results of stress analysis and wall deflection of evacuated chamber are presented.
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Sequential growth of GaN nanocrystals on SiO2 substrate modified by FIB method
Flajšmanová, Jana ; Voborný, Stanislav (referee) ; Mach, Jindřich (advisor)
This bachelor's thesis deals with the selective growth of gallium (Ga) and gallium nitride (GaN). In theoretical part, there is a brief description of growth of ultrathin films with respect to GaN and their manufacturing. Experimental part is aimed to the deposition of Ga and GaN on silicon substrates Si(1 1 1). Substrates with the native silicon dioxide layer (SiO2) were modified by focused ion beam (FIB). GaN was deposited by pulsed deposition followed by postnitridation. Prepared samples were studied by atomic force microscope (AFM), X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM).
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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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Design of the new type of thermal atomic source for oxygen atoms
Šikula, Marek ; Bábor, Petr (referee) ; Mach, Jindřich (advisor)
Ultrathin oxid layers (especially high-k layers) are studied and fabricated by using atomic oxygen sources. These high-k ultrathin layers are integrated into CMOS transistors and DRAM capacitors. In this thesis theory of atomic oxygen beams and ways of theirs creation is summarized. On the basis of the obtained knowledge the engineering design of a unique type of the thermal atomic oxygen source is created. The design was tested by simple experiments. The 3D model and complete engineering drawings are included.
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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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Selective growth of GaN layers on substrate modificated by method FIB
Mareš, Petr ; Voborný, Stanislav (referee) ; Mach, Jindřich (advisor)
The thesis deals with the selective growth of GaN crystals on the SiO2 layer. The theoretical part discusses the type of growth of ultrathin layers with focus on gallium nitride and its manufacturing. Moreover the text deals with principles of the focused ion beam and basic principles of other further methods which were used for analyzing the samples (AFM, XPS, photoluminescence spectroscopy). Experimental part consists of depositions of GaN. The silicon wafer Si(111) with native oxide SiO2 (1-2 nm) was used as a substrate. Focused ion beam was utilized to manufacture suitable structures on the substrate. Selective growth was acomplished with the use of the postnitridation method. Method of the pulse deposition was introduced with focus on increasing the volume of crystals.
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