Abstract In this study, ZrN films were deposited on silicon wafer¡Bcopper and aluminum sheets by reactive sputtering of Zr target at room temperature in a mixed N2-Ar atmosphere with N2 gas flow rates of 5 and 6 sccm. Films of ZrN about 1£gm thick were annealed at various temperatures in order to study the grain growth and the inter-diffusion of atoms. Electron probe X-ray microanalyzer¡]EPMA¡^ showed that the as-deposited ZrN films were stoichiometric. The ring patterns of electron diffraction in transmission electron microscope (TEM) indicated that only ZrN was present without any Zr metal. The grain size of ZrN showed no apparent change after annealing at 900¢J and 1000¢J, but showed that¡]200¡^ orientation is preferred to ¡]111¡^orientation. No Zr-Si compound were found at the ZrN/Si interface after annealing. It was revealed that the ZrN grain size in the ZrN/Si interface was about 5¡ã15 nm, then broadened to columnar structure of 20¡ã50nm in diameter away from the interface. The grain size of ZrN on Cu substrate was 3¡ã15 nm at the ZrN/Cu interface and leave away from the interface was 10¡ã80 nm. No Cu-Zr compound was found at the interface after annealing at 650¢J for 1 hour.

In this experiment the characteristics and microstructure of ZrN films between Si and Cu or Al were investigated. The ZrN films were deposited by RF magnetron reactive sputtering system. The ZrN films were annealed at various temperatures in order to observe the grain growth and the inter-diffusion of atoms between interfaces. X-ray analysis showed that in the ZrN/Al system the ZrN film has¡]220¡^preferred orientation after annealing at 600¢J for 1 hour. In the Al/ZrN/Si system of the same annealing condition, the ZrN film showed ¡]200¡^preferred orientation with the concurrent formation of the ZrSi2 and AlN phases. In the Cu/ZrN/Si system, the Cu film showed ¡]111¡^preferred orientation after annealing at 700¢J for 1 hour. TEM analysis showed that in the ZrN/Al system there were no Al-Zr compound was found after annealing at 600¢J for 1 hour. In the Al/ZrN/Si system, although ZrSi2¡BAlN and£\-Si3N4 were present after annealing at 600 ¢J for 1.5 hour, but the diffusion barrier is still effective. In the Cu/ZrN/Si system the CuZr2 was formed after annealing at 700¢J for 1 hour, but the diffusion barrier is also still effective. The results up to now suggest that ZrN layer can be a successful candidate as a diffusion barrier between Si and Cu or Al.

Abstract Recently Cu has been used as a replacement of Al in microelectronics industry to its lower electrical resistivity and higher electromigration resistance than aluminum. It is essential to have high performance diffusion barrier to suppress the diffusion between Cu and Si . In this experiment ZrN was investigated as a possible diffusion barrier. All coatings were deposited by RF magnetron reactive sputtering system. The growth of ZrN has been evaluted at different vacuum condition¡BRF power¡Bgrowth time¡BN2 flow rate Ar flow rate and Zr or ZrN target. The thin films were then annealed at temperatures from 450 ¢J to 700 ¢J for 30 min to study its durability. In this work XRD was used to study the thin film structure, SEM and TEM study the microstructures and AFM to study the surface roughness . The film¡¦s resistivity was measured as a function of N2 flow rate and annealing temperature by four point probe . For pure Zr film Cu3Si phase has formed after annealing at 550 ¢J for 30 min . As to ZrN film, only CuZr2 is present after annealing at 650 ¢J for 30 min indicating the diffusion barrier is still effective. After annealing at 700 ¢J for 30 min, Cu3Si was detected indicating the failure of the diffusion barrier. Results up to now suggest that ZrN layer can be a successful candidate as a diffusion barrier between Cu and Si.

The objective of this research was to design, assemble, and demonstrate the initial performance of a fluidized bed chemical vapor deposition (FB-CVD) system capable of producing thin, uniform zirconium nitride (ZrN) coatings (1 to 10 micrometers thick) on uranium-molybdenum (UMo) particulate fuel. Plate-type fuel with U-xMo (x = 3 to 10 wt.%) particle fuel dispersed in an aluminum matrix is under development at Idaho National Laboratory (INL) for the Reduced Enrichment for Research and Test Reactors (RERTR) program. Initial irradiation tests performed at INL in the Advanced Test Reactor (ATR) indicate an interaction layer forms between the fuel microspheres and the matrix at relatively high power levels. These power levels induce higher temperatures which enables uranium diffusion into the aluminum during irradiation, eventually causing fuel plate failure. The objective of this work was to create a process to mitigate the fuel/matrix interaction by forming a thin barrier coating on the surface of the U-xMo microspheres before incorporation into the dispersion fuel plate matrix. One of the main challenges in performance of the FB-CVD system was the effective fluidization of a powder whose physical characteristics (size, density) are continuously changing. To address this, two types of fluidized bed reaction vessels were designed and improved over the course of this research: a spouted fluidized bed and an inverted fluidized bed. Both reaction vessels utilized tetrakis(dimethylamino)zirconium (TDMAZ) and ammonia gas as precursors at atmospheric pressure. Tungsten wires and zirconia-silica (ZrO2-SiO2) microspheres were used as the substrates for the coating experiments. The substrate temperature and precursor gas flow were manipulated as the process variables. The FB-CVD system was successful in forming zirconium based coatings on surrogate microspheres with elevated levels of chemical impurities. At atmospheric pressure, coatings of thicknesses ranging from 0.5 micrometers to 1.5 micrometers were produced between temperatures of 250 degrees C and 350 degrees C. The deposited coatings were characterized using scanning electron microscopy, energy dispersive spectroscopy and wavelength dispersive spectroscopy.

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The topic of this Master thesis is The Monitoring of Biologically Active Substances of Coffee. The technological production of coffee beans from harvesting the crops to the final packaging is described in the theoretical part, together with the chemical composition of both green and roasted coffee beans. The next part sums up the current knowledge of biologically active substances that can be found in coffee and their effect on human health. The main focus has been put on phenolic compounds and their antioxidant properties. The last chapter of the theoretical part tells of modern ways which are used to define phenolic compounds. The practical part of the thesis identifies phenolic compounds in coffee beans of two kinds, Coffea arabica and Coffea canephora, roasted at different temperatures and in the range from very raw beans to over-roasted ones. A highly efficient High Performance Liquid Chromatography in connection with Mass Spectrometry has been used to detect the most significant phenolic compounds.

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Texture of igneous rocks, which includes size, shape and spatial distribution of grains, represents the final record of kinetic and mechanical processes operating during ascent and final emplacement of a magma. However, traditional geochemical approaches cannot assess and verify the physical processes of magma solidification, in particular, crystal nucleation and growth, textural coarsening, or mechanical crystal-melt interactions. In this work, I apply stereological methods to quantitatively characterize the textures and to interpret the crystallization history of granitic rocks in the Western Krušné hory/Erzgebirge and Vogtland. The Western Krušné hory/Erzgebirge granites consist of three suites: biotite granites (Kirchberg), muscovite-biotite microgranites (Walfischkopf), and topaz-zinnwaldite alkali- feldspar granites (Eibenstock), which consist of eight intrusive units and two aplite dyke sets. The entire granite sequence exhibits an extreme and nearly continuous differentiation range, but in detail the evolutionary trends of each suite are independent, and individual intrusive units are also clearly compositionally separated. The granites consist of 29-43 vol.% quartz, 20-30 vol. % plagioclase, 22-31 vol. % K-feldspar, 2-9 vol. % biotite, <2 vol. % muscovite, and minor topaz and apatite. All...

This Master thesis deals with the yield management evaluation and malting quality of chosen varieties of the spring malting barley in terms of half-working experiment in company "Kantor Václav - Agricultural businessman". There was chosen a stand of experiment and the values of yield management were observed, especially the number of plants, their offshoots and spikes per square unit, the quantity of grains in spikes, the weight of a thousand seeds and the yield. In case of the grain quality elements was rated a content of nitrogen substances, the drop above the sieve 2,8, 2,5, 2,2 mm and under the sieve 2,2 mm, then the content of amyloid, germination and its energy as well as the grain moisture. Among the rated varieties were placed: Malz, Sebastian, Laudis 550, Kangoo, Xanadu, Sunshine, Bojos, KWS Irina and Pionier. The results were filed in the tables and charts. The influence of variety on a different yield element was found out in the final comparison of all parameters. According to the aspect of the yield elements as well as the quality, the best values in this year taking experiment were reached by the Kangoo variety.