TY - JOUR A1 - Müller, Klaus A1 - Hoffmann, Patrick A1 - Milko, S. A1 - Burkov, Yevgen A1 - Schmeißer, Dieter T1 - PEEM and µ-NEXAFS of Cu-In-S-Surfaces N2 - 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. Y1 - 2002 ER - TY - JOUR A1 - Schmeißer, Dieter A1 - Paloumpa, Ioanna A1 - Hoffmann, Patrick A1 - Burkov, Yevgen A1 - Yfantis, Alexandros D. A1 - Yfantis, Alexandros D. T1 - Preventing Corrosion of Aluminium Alloys by Polymeric Coatings N2 - Aluminium is a material of everyday use in many applications,like automobile,aero-space or cookware,due to its specialproperties (low density,low weight,strength,easy to form and cast,abundance etc).Although aluminium is a reactive metal,italso has a significant corrosion resistance because of a thin,protective oxide layer which is generally stable in air and aqueous solutions.However,pores within the oxide film and other defects caused from alloying elements can lead to local corrosion and the formation of pits. Y1 - 2003 ER - TY - GEN A1 - Müller, Klaus A1 - Burkov, Yevgen A1 - Schmeißer, Dieter T1 - PEEM and my-NEXAFS of Cu-In-S2-surfaces T2 - Thin Solid Films N2 - Polycrystalline CuInS2 samples are an ideal system for photoemission electron microscope studies. The polycrystalline grains have a diameter of approximately 5 small mu, Greekm and the system is expected to be highly inhomogeneous because of the existence of many sub-phases. We used a recently established procedure to reproducibly obtain stoichiometric CuInS2-surfaces and follow the changes in the morphology, the elemental inhomogeneous distribution, and the development of the electronic structure upon its preparation. We find that the individual grains trend to coagulate, the surface composition becomes more homogeneous, and identify characteristic features of the unoccupied DOS. KW - CuInS2 films KW - Annealing-process KW - PEEM KW - small mu KW - NEXAFS Y1 - 2003 SN - 0040-6090 VL - 431-432 SP - 307 EP - 311 ER - TY - JOUR A1 - Paloumpa, Ioanna A1 - Yfantis, Alexandros D. A1 - Hoffmann, Patrick A1 - Burkov, Yevgen A1 - Yfantis, Alexandros D. A1 - Schmeißer, Dieter T1 - Mechanisms to inhibit corrosion of Al alloys by polymeric conversion coatings N2 - We introduce a recently developed novel polypyrrole-based coating, which can be formed on the aluminium surface from an aqueous pyrrole solution of fluorozirconic and fluorotitanic acid neutralised with zinc oxide. The composite layer consists of polypyrrole (Ppy) chemisorbed on titanium and zinc oxides and exhibits advanced corrosion resistance. For the investigation of the structure and the corrosion mechanism of the composite corrosion resistant layer we use a photo-electron emission microscope (PEEM). PEEM is especially suitable because it can deliver topographic contrast as well as elemental contrast and chemical information in connection with a variable X-ray source. Additionally, in order to investigate further the corrosion mechanism, but also the role of the alloy in the corrosion process, we examine the aluminium samples with SEM/EDX. The structure of the corrosion resistant layer was investigated before and after accelerated corrosion tests. Our results pointed out the important role of titanium oxide and zinc in the corrosion resistance of our Ppy coating on aluminium. KW - Polypyrrole KW - Fluorozirconates KW - Fluorotitanates KW - Aluminium KW - Corrosion Y1 - 2004 ER - TY - JOUR A1 - Burkov, Yevgen T1 - Comparison on Focus-PEEM and Elmitec-PEEM Y1 - 2004 ER - TY - GEN A1 - Müller, Klaus A1 - Goryachko, Andriy A1 - Burkov, Yevgen A1 - Schwiertz, Carola A1 - Ratzke, Markus A1 - Köble, J. A1 - Reif, Jürgen A1 - Schmeißer, Dieter T1 - Scanning Kelvin Probe Microscopy and Photoemission electron microscopy of organic source-drain structures T2 - Synthetic Metals N2 - n order to optimize organic field effect transistors (OFETs), the characterisation of active-layer surfaces in terms of their roughness, chemical composition and distribution of surface potentials is important. We report on high-resolution microscopic mapping of organic source-drain structures with P3HT as the semiconductor by scanning Kelvin probe microscopy (SKPM) and photoemission electron microscopy (PEEM). It was shown that PEEM is able to characterise the surface morphology (roughness), the chemical homogeneity and the composition of organic structures. The two-dimensional mapping of surface potentials by SKPM with applied source-drain voltages is shown to be an important ingredient of OFETs failure mode analysis. KW - Photoemission electron microscopy (PEEM) KW - Scanning Kelvin probe microscopy (SKPM) KW - OFET Y1 - 2004 SN - 0379-6779 VL - 146 IS - 3 SP - 377 EP - 382 ER - TY - CHAP A1 - Sidorenko, Alexander A1 - Tokarev, Igor A1 - Krenek, Radim A1 - Burkov, Yevgen A1 - Schmeißer, Dieter A1 - Minko, S. A1 - Stamm, Manfred ED - Champion, Yannick ED - Fecht, Hans-Jörg T1 - Generation of Nanostructured Materials from Thin Films of Block Copolymer Assembles T2 - Nano-architectured and manostructured materials, fabrication, control and properties, EUROMAT 2003 Y1 - 2004 SN - 3-527-31008-8 SP - 143 EP - 150 PB - Wiley-VCH CY - Weinheim ER - TY - GEN A1 - Tokarev, Igor A1 - Krenek, Radim A1 - Burkov, Yevgen A1 - Schmeißer, Dieter A1 - Sidorenko, Alexander A1 - Minko, Sergiy A1 - Stamm, Manfred T1 - Microphase separation in thin films of poly(styrene-block-4-vinylpyridine) Copolymer-2-(4-Hydroxybenzeneazo) benzoic Acid Assembly T2 - Macromolecules N2 - The fine structure of thin films of poly(styrene-block-4-vinylpyridine) copolymer-2-(4'-hydroxybenzeneazo)benzoic acid (PS-PVP+HABA) assembly has been studied using the combination of atomic force microscopy, ellipsometry, X-ray reflectivity, GISAXS, XPS, and XPEEM. The films consist of cylindrical nanodomains formed by PVP+HABA associates surrounded by PS matrix. Alignment of the domains can be switched upon exposure to vapors of different solvents from the parallel to perpendicular orientation and vice versa with respect to the surface plane. Swelling in 1,4-dioxane leads the system from the cylindrical to the spherical morphology. Solvent evaporation results in a shrinkage of the matrix in the vertical direction and subsequent merging of the spheres into the perpendicularly aligned cylinders. The cylinders form a regular hexagonal lattice with a spatial period of 25.5 nm. On the other hand, vapors of chloroform induce in-plane alignment. The films consist of parallel layers of the cylinders separated by PS matrix and demonstrate the fingerprint-like structure. The nanocylinders of PVP+HABA are packed into a distorted hexagonal lattice exhibiting 31 nm in plane and 17 nm vertical periodicity. In both cases a thin wetting layer is found at the polymer-substrate interface. The free surface is enriched with PS. Y1 - 2005 SN - 1520-5835 VL - 38 IS - 2 SP - 507 EP - 516 ER - TY - GEN A1 - Sidorenko, Alexander A1 - Tokarev, Igor A1 - Krenek, Radim A1 - Burkov, Yevgen A1 - Schmeißer, Dieter A1 - Stamm, Manfred T1 - XPEEM investigations of 2D hierachical array of Ni nanorods using block copolymer templates Y1 - 2004 ER - TY - JOUR A1 - Seifarth, Olaf A1 - Burkov, Yevgen A1 - Goryachko, Andriy A1 - Schmeißer, Dieter A1 - Sydorenko, Alexander A1 - Krenek, Radim A1 - Stamm, Manfred T1 - Photoelectron spectroscopy and microscopy on Cr nano particels embedded into block copolymers Y1 - 2005 ER - TY - JOUR A1 - Goryachko, Andriy A1 - Paloumpa, Ioanna A1 - Beuckert, Guido A1 - Burkov, Yevgen A1 - Schmeißer, Dieter T1 - The Interaction of Pr2O3 with 4H-SiC(0001)surface JF - Physica status solidi / C N2 - Praseodymium oxide (Pr2O3) as a hetero-oxide on SiC(0001) represents a promising semiconductor / high-K dielectric material combination. We prepared thin films (<3 nm) of Pr2O3 on 4H-SiC(0001) surfaces by a wet chemical process involving aqueous solutions of Pr(NO3)3. Synchrotron radiation photoelectron spectroscopy (SR-PES) is used to study the chemical composition of these films after deposition and annealing in 300-900 %B0C range. The Si2p and C1s core level emissions are analysed in detail and reveal that praseodymium-silicate is formed at the interface. Our data are compared to corresponding studies of the Pr2O3 interaction with Si(001) surfaces. Y1 - 2004 SN - 1610-1634 VL - 1 IS - 2 SP - 265 EP - 268 ER - TY - JOUR A1 - Müller, Klaus A1 - Scheer, R. A1 - Schmeißer, Dieter A1 - Burkov, Yevgen T1 - Preparation of stoichiometric CuInS2-Surfaces JF - Thin Solid Films KW - preparation Y1 - 2004 SN - 0040-6090 VL - 451–452 SP - 120 EP - 123 ER - TY - JOUR A1 - Müller, Klaus A1 - Burkov, Yevgen A1 - Schmeißer, Dieter T1 - Photo-Emission-Electron-Microscopy for Characterization of an Operating Organic Electronic Device KW - photo-emission-electron-microscopy Y1 - 2006 ER - TY - GEN A1 - Seifarth, Olaf A1 - Burkov, Yevgen A1 - Schmeißer, Dieter A1 - Stamm, Manfred T1 - Metallic nickel nanorod arrays embedded into ordered block copolymer templates T2 - Thin Solid Films Y1 - 2007 SN - 0040-6090 VL - 515 IS - 16 SP - 6552 EP - 6556 ER - TY - JOUR A1 - Henkel, Karsten A1 - Sohal, Rakesh A1 - Schmeißer, Dieter A1 - Schwiertz, Carola A1 - Burkov, Yevgen A1 - Torche, Mohamed T1 - Al-oxynitride buffer layer facilities for PrOx/SiC interfaces Y1 - 2007 ER - TY - JOUR A1 - Burkov, Yevgen ED - Vierhaus, Heinrich Theodor T1 - Dielectric Buffer Layer (Aluminium Oxynitride/AlON) for Ultrathin High-k Materials Y1 - 2007 ER - TY - JOUR A1 - Schmeißer, Dieter A1 - Burkov, Yevgen A1 - Paloumpa, Ioanna A1 - Mandal, Dipankar A1 - Henkel, Karsten T1 - Microscopic and Spectroscopic Characterization of Interfaces and Dielectric Layers for OFET Devices Y1 - 2008 ER - TY - GEN A1 - Henkel, Karsten A1 - Torche, Mohamed A1 - Sohal, Rakesh A1 - Karavaev, Konstantin A1 - Burkov, Yevgen A1 - Schwiertz, Carola A1 - Schmeißer, Dieter T1 - Pr-O-Al-N dielectrics for metal insulator semiconductor stacks KW - semiconductor KW - dielectric Y1 - 2011 ER - TY - GEN A1 - Wehner, Stefan A1 - Karpitschka, Stefan A1 - Burkov, Yevgen A1 - Schmeißer, Dieter A1 - Küppers, Jürgen A1 - Brand, Helmut R. T1 - Stochastic aspects of pattern formation during the catalytic oxidation of CO on Pd(111) KW - stochastic KW - pattern KW - catalytic oxidation Y1 - 2010 ER - TY - CHAP A1 - Müller, Klaus A1 - Burkov, Yevgen A1 - Mandal, Dipankar A1 - Henkel, Karsten A1 - Paloumpa, Ioanna A1 - Goryachko, Andriy A1 - Schmeißer, Dieter ED - Wöll, Christof T1 - Microscopic and spectroscopic characterization of interfaces and dielectric layers for OFET devices T2 - Organic Electronics : structural and Electronic Properties of OFETs KW - microscopic KW - spectrocsopic KW - dielectric Y1 - 2009 SN - 978-3-527-40810-8 SP - 445 EP - 468 PB - Wiley-VCH CY - Weinheim ER - TY - GEN A1 - Henkel, Karsten A1 - Burkov, Yevgen A1 - Karavaev, Konstantin A1 - Torche, Mohamed A1 - Schwiertz, Carola A1 - Schmeißer, Dieter T1 - Optimization of the AION buffer layer for PrxOy/Si stacks KW - AION buffer Y1 - 2009 ER -