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Organic materials for molecular quantum bits
Tuček, Marek ; Bábor, Petr (referee) ; Čechal, Jan (advisor)
In this thesis we briefly outline the properties and utilization of metal phthalocyanines, the procedure of iron phthalocyanine thin film deposition on Si(100), the supplementary post-deposition analysis by XPS and the equipment used to measure X-ray reflectivity. Further we describe the theoretical description of physical background of X-ray diffraction on a crystal, the measurement of X-ray reflectivity and evaluation of acquired data, focusing on determination of the thin film thickness, identification of its crystal structure and lattice parameters. It has been found out that iron phthalocyanine thin films deposited on a substrate at room temperature grow as an alpha-phase in the shape of needles perpendicular to substrate surface, so the film thickness, due to high rougness of the film, can be only estimated with the help of Scherrer equation for long depositions. In the case of shorter depositions (and thus lower roughness) the Kiessig fringes method can be used. By the post-deposition annealing we were not able to induce a phase transition; at required temperatures all the material on the substrate evaporated. By a deposition on a substrate heated to 160°C we acquired considerably rough film with unclear crystalline phase.
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SiO2 etching by Si deposition
Pokorný, David ; Bábor, Petr (referee) ; Polčák, Josef (advisor)
This bachelor thesis deals with one of the most interesting reactions taking place in the solid phase in UHV conditions and that is decomposition of SiO2 according to the equation Si + SiO2 = 2SiO. It was used the previously untested procedure - providing Si atoms not from substrate, but by direct deposition on the surface of the oxide. As a source of silicon atoms was used effusion cell. Deposition of silicon on SiO2 substrate was used at room temperature and at elevated temperature to clarify the principle of this reaction. The activation energy and temperature dependence of the reaction rate was determined. It was also verified the possibility of etching SiO2 by Si deposition in UHV conditions. The prepared samples were examined by x-ray photoelectron spectroscopy and atomic force microscopy.
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Correlative tomography
Vařeka, Karel ; Touš,, Jan (referee) ; Bábor, Petr (advisor)
Předložená diplomová práce se zabývá korelativním přístupem multimodální analýzy struktur prokovování s různým rozlišením. Výzkum je součástí mezinárodního projektu týkajícího se charakterizace poruch zmíněných struktur, které jsou implementovány v polovodičových zařízeních. Kombinace korelativní mikroskopie a tomografie technikami NanoXCT, FIB-SEM (EDS), FIB-SIMS a AFM byla navržena k zavedení opakovatelného pracovního postupu. Tomografie fokusovaným iontovým svazkem je metoda přesného odprašování v řezech, která mimo jiné v každém průřezu získává cenné snímky s vysokým rozlišením (FIB-SEM) nebo mapy chemického složení (FIB-SIMS). Následující transformace obrazu umožňuje identifikaci defektů jako funkci hloubky ve struktuře. Práce dále věnuje pozornost metodám sjednocení obrazů za účelem optimální prezentace získaných dat.
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Upgrade of the device for depositions by ion beam sputtering
Páleníček, Michal ; Mach, Jindřich (referee) ; Bábor, Petr (advisor)
This thesis deals with concept and realization of device which allows loading without air intake. Vacuum technology and its theoretical bases are discussed as well. Moreover the thesis is based on description of the current deposition chamber and its principles. The main part deals with the description of the concepts of lock and load systems. The first concept that has not been realized is described just briefly. The second one is thorough with description of the individual solutions and methods. The work also contains simple instructions how to install the specimen. At the end are described some outputs of simulations that have been done to comprehend and solve any problems that might occur as specimen holder cooling and deflection of magnetic rod.
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Analysis of advanced materials and structures by SIMS method
Holeňák, Radek ; Kalousek, Radek (referee) ; Bábor, Petr (advisor)
Bachelor theasis deals with the study of advanced materials by SIMS method and the possibilities of kvantitative analysis using maesured data. Chemical analysis of the ceramic surface in order to optimize the measurement conditions was performed. The rest of the work uses the data output from the measurement to describe the internal microstructure of the material. Using sophisticated methods, Si precipitates in the AlSi layer are localized and described, and the formation of the MgAl2O4 phase in ceramic samples is confirmed. Achieving all the set goals reveals the potential of the SIMS method and, above all, the possibility of processing the data output from the measurements.
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Development of the sample holder for electrical diagnostics in UHV SEM
Axman, Tomáš ; Pavera, Michal (referee) ; Bábor, Petr (advisor)
This bachelor thesis focuses on design and testing of a sample holder enabling for cooling and heating of the sample in ultra-high vacuum apparatus for scanning electron microscope, developed in cooperation with Tescan company. In the theoretical part the currently used sample holders in similar UHV systems are described and their positives and negatives are discussed including material selection. The experimental part describes designing of the sample holder with respect to the required number of electrical contacts for measuring electrical properties of the samples and UHV compatibility. Measurement and testing of the manufactured sample at low and high temperatures is presented.
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Design of aparature for RF plasma etching
Bárdy, Stanislav ; Bábor, Petr (referee) ; Mach, Jindřich (advisor)
This bachelor's thesis deals with a design of an ICP (Inductively Coupled Plasma) apparatus. The theoretical part consists of a research of a plasmatic graphene surface cleaning. Next are described plasma generation methods and an RF circuit design. The experimental part deals with a construction of the ICP apparatus and the impedance matching box, an optical diagnostics of a plasma discharge and a measurement of PMMA etching parameters (etch rate, roughness) by a spectroscopic reflectometry and an atomic force microscopy.
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