@article{Schmeisser, author = {Schmeißer, Dieter}, title = {Resonant photoemission at the Pr2O3 /Si(001) interface}, abstract = {In resonant photoemission studies photoelectron spectroscopy (PES) is done at photon ener-giesthat enable the excitation from a deep core hole to the empty conduction band states. Atresonant condition only such states are selectively enhanced which allow an optical couplingof the core hole to the empty conduction band states. Information is to be gained from theshape of the particular resonance and by a comparison of the valence band data at excitationenergies off and on resonance. Such studies provide information on the electronic structure, inparticular how to separate individual contributions in the valence band and conduction bandregime.}, language = {en} } @incollection{MuellerBaerHenkeletal., author = {M{\"u}ller, Klaus and B{\"a}r, Werner and Henkel, Karsten and Jahnke, Agnes and Schwiertz, Carola and Schmeißer, Dieter}, title = {Organische Feldeffekttransistoren als Transducer in der Biosensorik}, publisher = {w.e.b.-Univ.-Verl.}, address = {Dresden}, isbn = {3-935712-92-8}, pages = {119 -- 223}, language = {de} } @misc{SchmeisserMuessig, author = {Schmeißer, Dieter and M{\"u}ssig, Hans-Joachim}, title = {Stability and electronic properties of silicates in the system SiO2 - Pr2O3 - Si(001)}, series = {Journal of Physics: Condensed Matter}, volume = {16}, journal = {Journal of Physics: Condensed Matter}, number = {2}, issn = {1361-648X}, pages = {153 -- 160}, abstract = {Pr2O3 is one of the most promising hetero-oxides that are the candidates of choice to replace SiO2 as the gate dielectric material for sub-0.1 micrometer CMOS technology. In order to enable process integration, however, hetero-oxides require substantial characterization. In particular, the basic interaction mechanisms at the interface to the silicon substrate are the key issues. A solid knowledge of these mechanisms is required to address reliability arguments. The challenges in material science are to understand the chemical bonding of the hetero-oxides and Si on a microscopic scale. We report on the specific variations in the electronic structure which are evident in the valence band features around resonant excitation at the Pr 4d threshold. We also determine the valance band discontinuities at the Pr2O3/Si(001) interface and follow the changes in the surface potentials to develop a band scheme, a prerequisite to understanding the properties of charge transport across that interface.}, language = {en} } @article{PaloumpaYfantisHoffmannetal., author = {Paloumpa, Ioanna and Yfantis, Alexandros D. and Hoffmann, Patrick and Burkov, Yevgen and Yfantis, Alexandros D. and Schmeißer, Dieter}, title = {Mechanisms to inhibit corrosion of Al alloys by polymeric conversion coatings}, abstract = {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.}, language = {en} } @misc{SchmeisserMuessigDabrowski, author = {Schmeißer, Dieter and M{\"u}ssig, Hans-Joachim and Dabrowski, Jarek Marek}, title = {Silicate Layer Formation at the Pr2O3 / Si(001) Interfaces}, series = {Applied Physics Letters}, volume = {85}, journal = {Applied Physics Letters}, number = {1}, issn = {1077-3118}, pages = {88 -- 90}, abstract = {We studied Pr2O3/Si(001) interfaces by synchrotron radiation photoelectron spectroscopy and by ab initio calculations. We show that the interface formed during molecular-beam epitaxy under the oxygen partial pressure above 1\%D710-8 mbar consists of a mixed Si-Pr oxide, such as (Pr2O3)(SiO)x(SiO2)y. Neither an interfacial SiO2 nor an interfacial silicide is formed. The silicate formation is driven by a low energy of O in a PrOSi bond and by the strain in the subsurface SiOx layer. We expect that this natural interfacial Pr silicate will facilitate the integration of the high-k dielectric Pr2O3 into future complementary metal-oxide-semiconductor technologies.}, language = {en} } @article{Schmeisser, author = {Schmeißer, Dieter}, title = {Covalent and localized contributions of Pr4f states at the interface of Pr2O3 to Si(001)}, abstract = {Resonant photoelectron spectroscopy (PES) at the Pr4d and O1 s absorption edges is used to study the electronic properties at the interface of epitaxially grown Pr2O3 on Si(001).In the electronic structure of bulk Pr2O3, the valence band (VB) states are predominant of Pr6s and O2p atomic parentage. The contribution of Pr4f states is identified from the strong increase of the VB features at the Pr4d resonances. The data at the O1s edge are caused by Raman scattering and resonant Auger decay and reflect the existence of charge transfer (CT) complexes. These complexes are the consequence of a mixed valency caused by ligand-to-Pr4f charge transfer states. The decrease of their intensity is attributed to an increase in covalent bandwidth between the ligand (O2p, Si3p) and Pr4f states. The CT complexes, originally localized now, become broadened and form gap states which fill the gap towards a metallic density of states. The metallic phase may be hindered upon alloying with SiO2 or other oxides.}, language = {en} } @misc{LupinaDabrowskiFormaneketal., author = {Lupina, Grzegorz and Dabrowski, Jarek Marek and Formanek, Peter and Schmeißer, Dieter and Sorge, Roland and Wenger, Christian and Zaumseil, Peter and M{\"u}ssig, Hans-Joachim}, title = {Solid-state reaction between Pr and SiO2 studied by photoelectron spectroscopy and ab initio calculations}, series = {Materials Science in Semiconductor Processing}, volume = {7}, journal = {Materials Science in Semiconductor Processing}, number = {4-6}, issn = {1369-8001}, pages = {215 -- 220}, abstract = {We report on the structural and electrical properties of Pr-based high-k dielectric films fabricated by solid-state reaction between metallic Pr and SiO2 underlayers. A non-destructive depth profiling using synchrotron radiation excited photoelectron spectroscopy (SR-PES), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) were employed to examine the chemical composition and microstructure. Ab initio calculations were done to gain insight into the physical processes involved. SR-PES results indicate that Pr deposition at room temperature (RT) leads to the formation of a Pr silicide and a Pr oxide, what is in good agreement with the scenario expected from ab initio calculations. As revealed by TEM and electrical measurements, oxidation of the reacted structures, followed by annealing, results in a stacked dielectric composed of a SiO2-based buffer with an enhanced permittivity and a Pr silicate film with a high dielectric constant. The leakage current density of 10-4 A/cm2 was measured for stacks with capacitance equivalent thickness (CET) of 1.5 nm prepared by evaporation of the Pr layer on a 1.8 nm SiO2 film, followed by oxidation in air ambient and annealing in N2 atmosphere. The capacitance-voltage (C-V) curves exhibit a large flatband voltage (VFB) shift indicating the presence of a positive charge in the stack. Switching away from the Al contacts to Au gate electrodes introduces a significant reduction of the VFB by 1.3 eV, what is much more than the change expected from the work function difference between Al and Au (not, vert, similar0.9 eV). This in turn implies that VFB is strongly affected by the gate interface electrode.}, language = {en} } @misc{YfantisTzalasLambrakopoulosetal., author = {Yfantis, Alexandros D. and Tzalas, B. and Lambrakopoulos, S. and Anagnostaki, E. and Schmeißer, Dieter}, title = {New chrome free, environmentally friendly methods in chemical processes}, abstract = {It gives an overview of the research work to develop chrom-free methods in different chemical processes. A new class of materials, the conductive polymers, have been studied extensively for their anticorrosion properties.}, language = {en} } @misc{LewerenzMurrellJakubowiczetal., author = {Lewerenz, Hans-Joachim and Murrell, Chris and Jakubowicz, J. and Aggour, Mohammed and Kanis, M. and Campbell, S. A. and Cox, P. A. and Hoffmann, Patrick and Jungblut, H. and Schmeißer, Dieter}, title = {High Resolution Surface analysis of Si Roughenning in Dilute Ammonium Fluoride Solution}, series = {Journal of Electroanalytical Chemistry}, volume = {540}, journal = {Journal of Electroanalytical Chemistry}, issn = {1873-2569}, pages = {3 -- 6}, abstract = {The initial stages of porous Si formation on Si(111) in dilute ammonium fluoride solution are analysed by photoelectron spectroscopy using synchrotron radiation (SRPES). The PES results in the por-Si formation regime partly support a recent dissolution model. The contribution from the Si 2p surface core level shift shows that 0.35 ML of the surface is still H-terminated after interruption of the conditioning process at the first photocurrent maximum. Two signals shifted in binding energy by 0.8 and 1 eV, respectively, are attributed to reaction intermediates expected from the proposed reaction mechanism and from theoretical calculations using density functional theory (DFT). A distinct roughening is found in in-situ AFM measurements, with a calculated RMS roughness parameter of 2.6 nm.}, language = {en} } @misc{AppelAdeGuereketal., author = {Appel, G{\"u}nter and Ade, H. and G{\"u}rek, A. G. and Stadler, S. and Mikalo, Ricardo Pablo and Schmeißer, Dieter}, title = {Orientation studies of Si-Phthalocyanines sulfonic acids cast on SiOx substrates}, series = {Applied Physics / A}, volume = {76}, journal = {Applied Physics / A}, number = {2}, issn = {1432-0630}, doi = {10.1007/s003390201320}, pages = {177 -- 182}, abstract = {Layers of dihydroxy silicon phthalocyanine tetrasulfonic acid and oligo-7-oxo silicon phthalocyanine tetrasulfonic acid were prepared by solution-casting methods. The purity of the material was checked by X-ray photoemission spectroscopy. The orientation of the molecules in respect to the substrate plane was investigated by angle-dependent near-edge X-ray absorption fine-structure spectroscopy. The morphology was characterized by atomic force microscopy. Most samples exhibited a significant orientation that was accompanied by crystalline structures; others had no orientation at all with a dominant amorphous morphology. This behavior indicates that several preparation parameters affect the crystallinity and the orientation of the phthalocyanines.}, language = {en} } @misc{MuellerGoryachkoBurkovetal., author = {M{\"u}ller, Klaus and Goryachko, Andriy and Burkov, Yevgen and Schwiertz, Carola and Ratzke, Markus and K{\"o}ble, J. and Reif, J{\"u}rgen and Schmeißer, Dieter}, title = {Scanning Kelvin Probe Microscopy and Photoemission electron microscopy of organic source-drain structures}, series = {Synthetic Metals}, volume = {146}, journal = {Synthetic Metals}, number = {3}, issn = {0379-6779}, pages = {377 -- 382}, abstract = {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.}, language = {en} } @misc{MuessigDabrowskiWengeretal., author = {M{\"u}ssig, Hans-Joachim and Dabrowski, Jarek Marek and Wenger, Christian and Lupina, Grzegorz and Sorge, Roland and Formanek, Peter and Zaumseil, Peter and Schmeißer, Dieter}, title = {Ultrathin Dielectric Films Grown by Solid Phase Reaction of Pr with SiO2}, series = {MRS Proceedings}, volume = {811}, journal = {MRS Proceedings}, issn = {1946-4274}, pages = {D7.10.}, language = {en} } @misc{SchmeisserMuessig, author = {Schmeißer, Dieter and M{\"u}ssig, Hans-Joachim}, title = {Pr4f occupancy and VB/CB band offsets of Pr2O3 at the interface to Si(001) and SiC(0001) surfaces}, series = {MRS Proceedings}, volume = {811}, journal = {MRS Proceedings}, issn = {1946-4274}, pages = {D6.7}, language = {en} } @article{HoffmannSchmeisserSoinski, author = {Hoffmann, Patrick and Schmeißer, Dieter and Soinski, M. S.}, title = {Promieniowanie synchrotronowe jako uniwersalne narzedzie badawcze - Proby jego wykorzystania w badaniach struktury zeliwa}, language = {de} } @misc{YfantisPaloumpaSchmeisser, author = {Yfantis, Alexandros D. and Paloumpa, Ioanna and Schmeißer, Dieter}, title = {Corrosion Protection by Conductive Polymers for Magnesium Alloys}, series = {Magnesium, proceedings of the 6th International Conference on Magnesium Alloys and their Applications, November 2003 in Wolfsburg}, journal = {Magnesium, proceedings of the 6th International Conference on Magnesium Alloys and their Applications, November 2003 in Wolfsburg}, editor = {Kainer, Karl Ulrich}, publisher = {Wiley-VCH}, address = {Weinheim}, isbn = {3-527-30975-6}, pages = {605 -- 610}, abstract = {In this work, we present the experimental data related to the effect of the polypyrrole concentration and the film thickness on the corrosion inhibition properties of these novel polymer coatings. The relative corrosion resistance properties of the films formed from the matrix solutions, where polypyrrole was in situ polymerized and in cases where polypyrrole is dispersed in a form of powder (pigment) in the polyaclylic polymer, are further examined. The evaluation of the experimental data provides significant evidence regarding the mechanism of corrosion inhibition, as well as the optimization of the synthesis and application conditions.}, language = {en} } @inproceedings{SidorenkoTokarevKreneketal., author = {Sidorenko, Alexander and Tokarev, Igor and Krenek, Radim and Burkov, Yevgen and Schmeißer, Dieter and Minko, S. and Stamm, Manfred}, title = {Generation of Nanostructured Materials from Thin Films of Block Copolymer Assembles}, series = {Nano-architectured and manostructured materials, fabrication, control and properties, EUROMAT 2003}, booktitle = {Nano-architectured and manostructured materials, fabrication, control and properties, EUROMAT 2003}, editor = {Champion, Yannick and Fecht, Hans-J{\"o}rg}, publisher = {Wiley-VCH}, address = {Weinheim}, isbn = {3-527-31008-8}, pages = {143 -- 150}, language = {en} } @misc{TokarevKrenekBurkovetal., author = {Tokarev, Igor and Krenek, Radim and Burkov, Yevgen and Schmeißer, Dieter and Sidorenko, Alexander and Minko, Sergiy and Stamm, Manfred}, title = {Microphase separation in thin films of poly(styrene-block-4-vinylpyridine) Copolymer-2-(4-Hydroxybenzeneazo) benzoic Acid Assembly}, series = {Macromolecules}, volume = {38}, journal = {Macromolecules}, number = {2}, issn = {1520-5835}, pages = {507 -- 516}, abstract = {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.}, language = {en} } @incollection{HenkelSchwiertzWagneretal., author = {Henkel, Karsten and Schwiertz, Carola and Wagner, S. and Valdeig, A. and List, M. and Schmeißer, Dieter}, title = {Partikel- und Tropfendetektion im Mikrometerbereich mittels Schwingquarzen}, publisher = {w.e.b.-Univ.-Verl.}, address = {Dresden}, isbn = {3-935712-92-8}, pages = {291 -- 294}, language = {de} } @misc{LamprakopoulosSchmeisserAnastassopoulouetal., author = {Lamprakopoulos, Stelios and Schmeißer, Dieter and Anastassopoulou, Jane and Theophanides, Theophile and Yfantis, Alexandros D.}, title = {An FTIR study of the role of H2O and D2O in the aging mechanism of conductive polypyrroles}, series = {Synthetic Metals}, volume = {144}, journal = {Synthetic Metals}, number = {3}, issn = {0379-6779}, doi = {10.1016/j.synthmet.2004.03.006}, pages = {229 -- 234}, abstract = {In the present work the role of H2O was studied by conductivity measurements and FTIR spectroscopy using the isotopic effect of deuterium in order to elucidate the aging mechanism of conductivity of polypyrroles. Polypyrrole was prepared with PTS as a dopant, by using deuterated water. Conductivity measurements showed changes due to structural water and atmospheric humidity. The FTIR absorption spectra indicated that the most probable structure of polypyrrole is the two-dimensional one. This finding could be attributed to the inhibition of polypyrrole's IR modes. The infrared spectrum analysis show that the gamma -NH bending mode of pyrrole has significantly changed after polymerization of pyrrole and this result is in accordance with XPS measurements.}, language = {en} } @article{Schmeisser, author = {Schmeißer, Dieter}, title = {Pr2O3/Si(001) interface reactions and stability}, abstract = {We show that an interfacial silicate is formed in a natural way between Si(0 0 1) and the deposited Pr2O3 film if a sufficient amount of oxygen is provided during deposition, as during electron beam evaporation from Pr6O11 source. We provide arguments from results of ab initio calculations and we present a ternary phase diagram of the Pr-O-Si system obtained for epitaxial films from non-destructive depth profiling data acquired by synchrotron radiation and photoelectron spectroscopy (SR-PES) at the undulator beam line U49/2-PGM2. The composition of the interfacial layer is (Pr2O3)(SiO)x(SiO2)y, with x+y between 2 and 6 and depends on the growth condition and distance from the substrate. No interfacial SiO2 and no interfacial silicide is formed during growth. The ternary phase diagram indicates that this non-stoichiometric pseudobinary alloy is stable on Si up to high temperatures, without phase separation into Pr2O3 and SiO2. Therefore, a complete re-engineering of the CMOS process may be not necessary.}, language = {en} } @misc{SidorenkoTokarevKreneketal., author = {Sidorenko, Alexander and Tokarev, Igor and Krenek, Radim and Burkov, Yevgen and Schmeißer, Dieter and Stamm, Manfred}, title = {XPEEM investigations of 2D hierachical array of Ni nanorods using block copolymer templates}, language = {de} } @article{Schmeisser, author = {Schmeißer, Dieter}, title = {Cooper minimum observed for the Pr5s and Pr5p states in Pr2O3}, language = {en} } @incollection{SchmeisserLupinaMuessig, author = {Schmeißer, Dieter and Lupina, Grzegorz and M{\"u}ssig, Hans-Joachim}, title = {High reactivity of Pr on oxide covered 4H-SiC}, series = {Bessy annual report 2003}, booktitle = {Bessy annual report 2003}, publisher = {Bessy}, address = {Berlin}, pages = {408 -- 409}, language = {en} } @article{Schmeisser, author = {Schmeißer, Dieter}, title = {Interface reactivity of Pr and SiO2 at 4H-SiC(0001)}, abstract = {We use photoelectron spectroscopy to characterize the reactivity of Pr evaporated on SiO2 covered 4H-SiC substrates. We analyze the Si2p, C1s, and O1s core levels and find that Pr reacts at RT with the SiO2 layer to form Pr-silicate. In addition also Pr-silizide is formed as well as Pr-carbides. While the latter are formed as reaction intermediates after Pr evaporation, the Pr-silicate layer is formed upon annealing to 300 °C and is stable up to 800 °C.}, language = {en} } @article{Schmeisser, author = {Schmeißer, Dieter}, title = {Pr4f occupancy and origin of gap states at the Pr2O3 / Si (001) interface}, language = {en} }