@article{MuellerHoffmannMilkoetal., author = {M{\"u}ller, Klaus and Hoffmann, Patrick and Milko, S. and Burkov, Yevgen and Schmeißer, Dieter}, title = {PEEM and µ-NEXAFS of Cu-In-S-Surfaces}, abstract = {The composition of CuInS2-films tends to differ from the ideal ratio of 1:1:2. A molecularlyvariation of dm=[Cu]/[In]-1 not equal 0 occurs due to the formation of binary phases as segregation's at the surface, as crystallites in the bulk of the film or at the surface of grains [1]. Furthermore, the range of homogeneity of the phase CuInS2 is relatively large caused by a low enthalpy of formation of defects like Cu-vacancies [2]. Segregation's at surfaces can be removed by KCN etching or by an electrochemical process [3, 4] We investigated the effect of an in-situ-heat-treatment of samples, prepared in the Cu-rich regime with additional amounts of copper, deposited on the surface of the Cu-In-S-films.We used Cu-In-S-films on molybdenum, prepared from precursors of Cu/In and a following reactive annealing-process in a sulphur-atmosphere. The experiments were performed as follows: The surface of the films was cleaned in situ to remove CuS-Phases by Argon-bombardment. The thin layers of additional Copper were prepared by evaporation of copper metal in Knudsen-cells. The thickness of this copper-films is in the range of monolayers, revealed by a calibration with copper on iron-substrates. After this deposition the samples were heated up to several temperatures (up to 550 ºC) for ten minutes, respectively. Here the molybdenum back-contact was used as electrical heater.}, language = {en} } @misc{MuellerHenkelMikaloetal., author = {M{\"u}ller, Klaus and Henkel, Karsten and Mikalo, Ricardo Pablo and Paloumpa, Ioanna and Schmeißer, Dieter}, title = {Elektronik mit organischen Materialien}, publisher = {BTU Cottbus, Eigenverlag}, abstract = {Plastikelektronik, flexible Solarzellen, intelligente Kleidung, neuartige und maßgeschneiderte Transducer f{\"u}r die Gas-, Fl{\"u}ssigkeits- und Biosensorik, all dies sind Anwendungen, die ohne halbleitende Polymere nicht denkbar w{\"a}ren und die Bereiche erschließen, in denen zur Zeit eine regelrechte Goldgr{\"a}berstimmung herrscht. Mit wichtigen Beitr{\"a}gen im Grundlagen- und Anwendungsbereich nimmt die BTU Cottbus an dieser Entwicklung teil, u. a. auch durch eine Kooperation mit dem Institut f{\"u}r Mikrobiologie des Carl-Thiem-Klinikums Cottbus.In diesem Artikel werden die Voraussetzungen f{\"u}r die Konstruktion organischer Feldeffekt-Transistoren mit gassensitiver Gate-Elektrode vorgestellt. Untersuchungen zur elektronischen Struktur des organischen Halbleiters Poly(3-Hexylthiophen), die Anwendung dieses Materials als aktive Schicht in organischen Feldeffekt-Transitoren, die Gassensitivit{\"a}t von Polypyrrolelektroden auf Quarz-Mikrowaagen und die Mikrorstukturierung organischer Elektroden werden beschrieben.}, language = {de} } @incollection{SchwiertzHenkelPaloumpaetal., author = {Schwiertz, Carola and Henkel, Karsten and Paloumpa, Ioanna and Schmeißer, Dieter}, title = {Sensorsystem zur Unterscheidung von Geruchsmustern in Tierst{\"a}llen}, abstract = {Es wurde ein kontinuierlich arbeitendes, preiswertes Schwingquarz-Mess-System zur olfaktometrischen {\"U}berwachung von Tierst{\"a}llen aufgebaut, mit dessen Hilfe im Arbeitsbereich von 65\%B0C spezifische Ger{\"u}che verschiedener Tierarten unterschieden werden k{\"o}nnen. Zur Geruchsmustererkennung wurde ein einfaches neuronales Netz verwendet. Olfaktometrische Verd{\"u}nnungen auf 33\% sowie Messwertschwankungen von 5-10\% wurden simuliert, wobei die richtige Musterzuordnung durch das Netz nicht beeinflusst wurde.}, language = {de} } @inproceedings{Egbers, author = {Egbers, Christoph}, title = {Observation of Nanoparticle Aggregation in a tube flow under microgravity conditions}, series = {34th COSPAR Scientific Assembly, The Second World Space Congress, held 10-19 October, 2002 in Houston, TX, USA., meeting abstract}, booktitle = {34th COSPAR Scientific Assembly, The Second World Space Congress, held 10-19 October, 2002 in Houston, TX, USA., meeting abstract}, language = {en} } @article{HoffmannMikaloSchmeisser, author = {Hoffmann, Patrick and Mikalo, Ricardo Pablo and Schmeißer, Dieter}, title = {PEEM - a spectromicroscopic tool for mc-Si surface evaluation}, abstract = {The photo emission electron microscope (PEEM) with its direct imaging of the sample surface is a convenient tool for fast evaluation of large sample areas. It is possibleto handle samples with a size of 30 mm x 30 mm.With PEEM it is possible to visualise grain boundaries and crystal displacements without removing the native oxide. No special sample treatment is needed exceptchemical polishing of the sample surface and a HF-dip to obtain a thin (1 ... 2 nm) oxide layer.The quality of that oxide was proofed by high resolution photo electron spectroscopy (PES) at a synchrotron. The results were compared to native oxide onsingle-crystalline Si and no suboxides (e.g. SiO) were found. Our spectromicroscopic PEEM measurements show no difference in the oxide qualities of different grainsand on grain boundaries or crystal displacements. Furthermore no difference in the binding energy of Si2p core levels were found.In addition to grain boundaries other spot-like features were found on the sample surface. These could be identified in some cases as precipitation of Ca underneath thenative oxide.}, language = {en} } @misc{AggourStoerkelMurrelletal., author = {Aggour, Mohammed and Stoerkel, Ulrich and Murrell, Chris and Campbell, S. A. and Jungblut, H. and Hoffmann, Patrick and Mikalo, Ricardo Pablo and Schmeißer, Dieter and Lewerenz, Hans-Joachim}, title = {Electrochemical interface modification of CuInS2 thin films}, abstract = {We studied two novel electrochemical treatments of CuInS2 solar-cell absorber films, introduced to remove the deleterious segregated CuS phase. Their influence onsurface topography, chemistry and electronic properties was investigated using in situ atomic force microscopy (AFM) and photoclectron spectroscopy, performed inpart at the U49/2 undulator beam line at BESSY II. The results are examined in order to develop an improved understanding of the chemical-electrochemical surfacetransformation processes.}, language = {en} } @inproceedings{Futterer, author = {Futterer, Birgit}, title = {3D-FG-Widerstandsmodellierung: Analyse von Diskretisierungsfehlern bei gitterunabh{\"a}ngiger Elektrodenpositionierung}, series = {19. Kolloquium Elektromagnetische Tiefenforschung, Burg Ludwigstein, 1.10.-5.10.2001}, booktitle = {19. Kolloquium Elektromagnetische Tiefenforschung, Burg Ludwigstein, 1.10.-5.10.2001}, publisher = {Dt. Geophysikalische Ges.}, address = {Potsdam}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:b103-emtf197}, pages = {111 -- 119}, language = {de} } @article{YfantisPaloumpaSchmeisseretal., author = {Yfantis, Alexandros D. and Paloumpa, Ioanna and Schmeißer, Dieter and Yfantis, Alexandros D.}, title = {Novel corrosion-resistant films for Mg alloys}, abstract = {A novel method for the corrosion inhibition of Mg, alloys, based on the formation of a thin polyacrylic-polypyrrole film, is presented. The film was created after simpleimmersion of the samples in a specially formulated emulsion of polyacrylic and polypyrrole polymers. The synthesis conditions were studied, as well as the resultingcorrosion resistance of coated magnesium foils (AZ31) in terms of corrosion rate in neutral aqueous NaCl solutions. The relative ratio of polyacrylic polymer topolypyrrole was found to be important for the film properties. Furthermore, only in situ polymerisation of pyrrole in the polyacrylic emulsion can provide advancedcorrosion proper-ties in relatively thin films (2-5 mum). Blending of polypyrrole powder with the polyacrylic emulsion gives rise to thick films (20 mum) with reducedcorrosion-inhibition properties. The corrosion rate was only weakly dependent on the film thickness of these novel coatings. We argue that the mechanism of corrosioninhibition is related to the formation of a thin passive layer of chemisorbed polypyrrole polymers or oligomers on the native magnesium oxide of the C surface. Thestructure is further stabilised by polyacrylic polymer chains interacting as dopants of polypyrrole. The method is environmentally friendly: non-toxic chemicals are used,no rinsing is required, etc. The advanced corrosion-inhibition properties of the films. as well as the simple application process on the metal surface, provide significantpotential for the industrial application of the method.}, language = {en} } @article{HoffmannMikaloSchmeisser, author = {Hoffmann, Patrick and Mikalo, Ricardo Pablo and Schmeißer, Dieter}, title = {Si(001) surface oxidation by N2O}, abstract = {Ultra-thin homogeneous oxynitride films are prepared on Si(001). The Si surface is cleaned in UHV by heating (flashing) and is exposed to different pressures of N2Oat altered temperatures. Thus oxynitride layers of different thickness and different properties are grown depending on the N2O pressure and the Si temperature. This isillustrated by a schematic diagram. The properties of the different oxynitride layers were studied by a combined photoemission electron microscopy (PEEM) andphotoelectron spectroscopy (PES) investigation using highly monochromatic synchrotron radiation. The amount of oxygen and nitrogen incorporated in the oxynitridelayers is determined from the PES measurements. The typical surface morphology for different preparation conditions is shown in PEEM images.}, language = {en} } @article{MikaloSchmeisser, author = {Mikalo, Ricardo Pablo and Schmeißer, Dieter}, title = {Electric contacts on conductive polymers: sodium on poly(3-hexylthiophene-2,5-diyl)}, abstract = {Sodium as a model contact with low work function on regioregular poly(3-hexylthiophene-2,5-diyl) (P3HT) films was investigated. The interface was studied by X-rayand ultraviolet photoelectron spectroscopy in the range of 0.13 up to 1.8 metal atoms per hexylthiophene unit. In the range of 0.13-0.26 sodium atoms per hexylthiophenering we find a change inthe surface potentials which is interpreted as a discharge of positive surface charges. Sodium exposures above 0.5 sodium atoms perhexylthiophene unit exhibit a reduction of the thiophene sulfur due to the formation of sodium sulfide and breaking of the thiophene ring.}, language = {en} } @misc{LewerenzAggourMurrelletal., author = {Lewerenz, Hans-Joachim and Aggour, Mohammed and Murrell, Chris and Kanis, M. and Hoffmann, Patrick and Jungblut, H. and Schmeißer, Dieter}, title = {Interface engineering of photoelectrochemically prepared Si surfaces}, abstract = {The oxide of Si(111) formed by electropolishing in dilute ammonium fluoride solution is analysed by photoelectron spectroscopy using synchrotron radiation. The oxidiclayer is about 3.1 nm thick and contains Si-F-x species as well as oxyfluorides. The oxyfluorides are found preferentially at the electropolishing layer surface. SiOHspecies are concentrated at the oxidic film/substrate interface. The full width half maximum of the Si 2p line indicates that the Si/electropolishing oxide interface issmoother than the Si/natural oxide interface.}, language = {en} } @inproceedings{LarcherEgbers, author = {Larcher, Thomas von and Egbers, Christoph}, title = {LDA-Messungen zur Untersuchung barokliner Instabilit{\"a}ten, Lasermethoden in der Str{\"o}mungsmesstechnik}, language = {de} } @article{SieberSeyllerGraupneretal., author = {Sieber, N. and Seyller, Th. and Graupner, R. and Ley, L. and Mikalo, Ricardo Pablo and Hoffmann, Patrick and Batchelor, David R. and Schmeißer, Dieter}, title = {Wet-chemical preparation of silicate adlayer reconstructed SiC(0001) surfaces as studied by PIES and LEED}, abstract = {We have studied the surface chemistry of 6H-SiC(0001) and 6H-SiC (000 (1) over bar) after wet-chemical treatment using photoelectron spectroscopy (PES) andlow-energy electron diffraction (LEED). The origin of chemically shifted components in the Si2p and C1s spectra is discussed in the light of previous studies onwet-chemically prepared surfaces and on silicate adlayer reconstructed surfaces. On 6H-SiC(0001) an ordered silicate adlayer was prepared by etching the surface withsulfuric acid based agents.}, language = {en} } @inproceedings{Egbers, author = {Egbers, Christoph}, title = {Simulation of Geophysical Fluid Flows under Microgravity (GeoFlow): Flow diagnostics and experiment concept for Fluid Science experiments}, series = {Proceedings of 11th International Symposium on Applications of Laser Techniques to Fluid Mechanics, Lisbon, 8-11th July 2002}, booktitle = {Proceedings of 11th International Symposium on Applications of Laser Techniques to Fluid Mechanics, Lisbon, 8-11th July 2002}, pages = {5}, language = {en} } @inproceedings{Futterer, author = {Futterer, Birgit}, title = {Minimierung von Diskretisierungsfehlern bei gitterunabh{\"a}ngiger Elektrodenpositionierung}, series = {62. Jahrestagung der Deutschen Geophysikalischen Gesellschaft im Jahr der Geowissenschaften}, booktitle = {62. Jahrestagung der Deutschen Geophysikalischen Gesellschaft im Jahr der Geowissenschaften}, publisher = {Deutsche Geophysikalische Gesellschaft}, address = {Hannover}, language = {de} } @incollection{RollandArnold, author = {Rolland, Wolfgang and Arnold, Ingolf}, title = {Anthropogene Ver{\"a}nderungen des Wasserhaushaltes der Spree vom 15. bis 19. Jahrhundert}, series = {Die Niederlausitz vom 18. Jahrhundert bis heute: eine gest{\"o}rte Kulturlandschaft?}, booktitle = {Die Niederlausitz vom 18. Jahrhundert bis heute: eine gest{\"o}rte Kulturlandschaft?}, editor = {Bayerl, G{\"u}nter}, publisher = {Waxmann}, address = {M{\"u}nster [u.a.]}, isbn = {3-8309-1197-1}, pages = {199 -- 235}, language = {de} } @article{RichterWichter, author = {Richter, Frank and Wichter, Lutz}, title = {Zur Bemessung von wasserdurchl{\"a}ssigen Pflaster- und Plattenbel{\"a}gen}, language = {de} } @inproceedings{WichterKuegler, author = {Wichter, Lutz and K{\"u}gler, Marcus}, title = {Fehlstellen in D{\"u}senstrahlk{\"o}rpern durch Inhomogenit{\"a}ten im Baugrund}, series = {Vortr{\"a}ge der Baugrundtagung 2002 in Mainz}, booktitle = {Vortr{\"a}ge der Baugrundtagung 2002 in Mainz}, publisher = {Gl{\"u}ckauf-Verlag}, address = {Essen}, isbn = {3-7739-5968-0}, pages = {99 -- 105}, language = {de} } @inproceedings{Gruenewald, author = {Gr{\"u}newald, Uwe}, title = {"Oderflut 1997" - "Weichselflut 2001" - "Elbeflut 2002"}, series = {Die Gefahrentage des DKKV Leipzig 2001/Potsdam 2002 : Dokumentation von Vortr{\"a}gen}, booktitle = {Die Gefahrentage des DKKV Leipzig 2001/Potsdam 2002 : Dokumentation von Vortr{\"a}gen}, publisher = {DKKV}, address = {Bonn}, isbn = {3-933181-30-5}, pages = {62 -- 67}, language = {de} } @book{Achermann, author = {Achermann, Jo}, title = {"Kunstweg, Alpanstad Alpnach Dorf"}, publisher = {Wallimann}, address = {Alpnach}, isbn = {3-908713-25-0}, pages = {50}, abstract = {Anl{\"a}sslich der 300-Jahr-Feier Kapelle St. Josef in Alpnachstad}, language = {de} }