@article{SieberMantelSeylleretal., author = {Sieber, N. and Mantel, B. F. and Seyller, Th. and Ristein, J. and Ley, L. and Heller, Thomas and Batchelor, David R. and Schmeißer, Dieter}, title = {Electronic and chemical passivation of hexagonal 6H-SiC surfaces by hydrogen termination}, language = {en} } @inproceedings{BatchelorBergSimonetal., author = {Batchelor, David R. and Berg, A. and Simon, Sylvio and Wagner, Lothar and Viehweger, Bernd and Schmeißer, Dieter}, title = {Development of Joining Techniques through Pressforming of Steel and Aluminium}, language = {en} } @inproceedings{HenkelEllingDanzetal., author = {Henkel, Karsten and Elling, B. and Danz, R. and B{\"u}chtemann, A. and Straube, Oliver and Paloumpa, Ioanna and Yfantis, Alexandros D. and Schmeißer, Dieter}, title = {Piezoelectric polymer sensor for high pressures in forming machines}, language = {en} } @inproceedings{HuleaHoffmannBrinzaetal., author = {Hulea, Iulian and Hoffmann, Patrick and Brinza, Monica and Batchelor, David R. and Schmeißer, Dieter}, title = {The interface of friction-welded Al-Fe joints. ATB Metallurgy}, language = {en} } @inproceedings{JaegermannSchmeisser, author = {Jaegermann, Wolfram and Schmeißer, Dieter}, title = {Elementary Processes at Solid/Electrolyte Interfaces}, language = {en} } @inproceedings{YfantisTsiniarakisLabrakopoulosetal., author = {Yfantis, Alexandros D. and Tsiniarakis, G. and Labrakopoulos, S. and Yfantis, Alexandros D. and Schmeißer, Dieter}, title = {Conductive polymers of pyrrole as pigments in organic anticorrosive coatings-application for aluminium alloys}, language = {en} } @misc{LewerenzAggourMurrelletal., author = {Lewerenz, Hans-Joachim and Aggour, Mohammed and Murrell, Chris and Kanis, M. and Jungblut, H. and Jakubowicz, J. and Cox, P. A. and Campbell, S. A. and Hoffmann, Patrick and Schmeißer, Dieter}, title = {Initial stages of structure formation on silicon electrodes investigated by photoelectron spectroscopy using synchrotron radiation and in-situ atomic force microscopy}, series = {Journal of the Electrochemical Society}, volume = {150}, journal = {Journal of the Electrochemical Society}, number = {3}, issn = {1945-7111}, pages = {E185 -- E189}, abstract = {The surface condition of electrochemically H-terminated Si is compared with the situation at the first photocurrent maximum in dilute acidic ammonium fluoride solution where the divalent dissolution converts into the four-valence process. The first high spectral-resolution photoelectron spectroscopy data using synchrotron radiation of electrochemically hydrogenated Si are presented. A combined electrochemistry/ultrahigh vacuum surface analysis system, attached to the U 49/2 beamline at the synchrotron Bessy II, is used for photoelectron spectroscopy (PES) of the electrochemically conditioned samples. We analyze the Si 2p, O 1s, and F 1s core levels. A comparison of a density functional theory calculation of the reaction sequence, proposed in the dissolution model of Gerischer and co-workers, with the PES results supports this model. The anodized sample is characterized by a residual H coverage of 0.35 monolayers evidenced by a surface core level shift, Si-OH and Si-Fx species, F-, and a higher oxidized Si species. SiO2 is not found. Even on very well H-terminated surfaces, we find residual Si-OH complexes, fluoride and water. In situ atomic force microscopy shows a roughening with a root mean square roughness parameter of 2.6 nm. \%A92003 The Electrochemical Society. All rights reserved.}, language = {en} } @misc{HoffmannSchmeisserRotersetal., author = {Hoffmann, Patrick and Schmeißer, Dieter and Roters, G. and Nenyei, Z.}, title = {Non-destructive probing of interfacial oxidation and nitridation states at RTA Si-oxides}, series = {Thin Solid Films}, volume = {428}, journal = {Thin Solid Films}, number = {1-2}, issn = {0040-6090}, pages = {216 -- 222}, abstract = {The quality of the SiO2/Si interface is of crucial importance in the development and performance of sub 0.1 small mu, Greekm technologies. The knowledge of the chemical composition of the interface is an important piece of information in the preparation of ultra-thin oxides and high-k dielectrics, in order to maintain a high-quality interface and channel mobility. Here we report on investigations of 2 nm oxide layers formed by a RTP process under various gas mixtures containing N2O and NH3 at different concentrations. We studied the SiO2/Si(001) interface by a non-destructive depth profiling using Synchrotron radiation photoelectron spectroscopy. We determine the thickness of the oxide layer, the relative content and chemical state of nitrogen within the oxide, the thickness of the interface layer, and the relative abundance of Si intermediate oxides within. In all systems we find the thickness of the intermediate layer to be approximately 0.17 nm. The intermediate layer contains Si atoms in the oxidation states +1, +2 and +3 with similar relative abundance. Nitrogen is found predominantly close to the intermediate layer forming Si---N as well as Si---N---O bonds. Within the oxide there are only spurious nitrogen content with predominately Si---N---O bonds. Our method is able to detect a nitrogen content within the intermediate layer as low as approximately 5\%.}, language = {en} } @article{SchmeisserPaloumpaHoffmannetal., author = {Schmeißer, Dieter and Paloumpa, Ioanna and Hoffmann, Patrick and Burkov, Yevgen and Yfantis, Alexandros D. and Yfantis, Alexandros D.}, title = {Preventing Corrosion of Aluminium Alloys by Polymeric Coatings}, abstract = {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.}, language = {en} } @article{MuellerMilkoSchmeisser, author = {M{\"u}ller, Klaus and Milko, S. and Schmeißer, Dieter}, title = {Preparation of stoichiometric CuInS2-surfaces - an XPS, UPS-study}, series = {Thin Solid Films}, volume = {431-432}, journal = {Thin Solid Films}, issn = {0040-6090}, pages = {312 -- 316}, abstract = {CuInS2 films are investigated with photoelectron spectroscopy. We find significant deviation from the stoichiometric composition depending on the preparation on the films. For Cu-rich films (start composition) we show that by Ar sputtering and annealing the surface composition varies along a binary cut of the Cu-In-S ternary phase diagram. We also present a novel technique which brings the surface composition close to the stoichiometric stability range of the CuInS2 phase. The technique used the evaporation of Cu on the sputter cleaned surface.}, language = {en} } @misc{MuellerBurkovSchmeisser, author = {M{\"u}ller, Klaus and Burkov, Yevgen and Schmeißer, Dieter}, title = {PEEM and my-NEXAFS of Cu-In-S2-surfaces}, series = {Thin Solid Films}, volume = {431-432}, journal = {Thin Solid Films}, issn = {0040-6090}, pages = {307 -- 311}, abstract = {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.}, language = {en} } @misc{Schmeisser, author = {Schmeißer, Dieter}, title = {Valence states of poly(3-hexyl-thiophene) as probed by photoelectron spectra at resonant excitation}, series = {Synthetic Metals}, volume = {138}, journal = {Synthetic Metals}, number = {1-2}, issn = {0379-6779}, pages = {135 -- 140}, abstract = {Photoelectron spectroscopy employing synchrotron radiation is applied to learn about the electronic structure of regio-regular poly(3-hexyl-thiophene) (P3hT). We study the valence band photoelectron spectra around the carbon 1s threshold. This technique is equivalent to resonant excitation of core electrons into empty valence states. We probe the properties of these carriers in the conduction band and also learn about valence band states involved in the carbon (K L L) Auger transitions. The data give evidence that monomeric orbital energies are dominating in such processes. We conclude that poly(3-hexyl-thiophene) is a polymer with a rather short conjugation length.}, language = {en} } @misc{MuellerPaloumpaSchmeisser, author = {M{\"u}ller, Klaus and Paloumpa, Ioanna and Schmeißer, Dieter}, title = {Carbon-plot-microstructuring for all-polymer-transistors}, series = {Synthetic Metals}, volume = {138}, journal = {Synthetic Metals}, number = {1-2}, issn = {0379-6779}, pages = {271 -- 273}, abstract = {This contribution describes the use of a low-cost technology to produce organic microstructures for electronically applications. With a computer driven plotter, substrates like printing foil and colloidal graphite (diluted in water) for the electrodes, we realised channel lengths of 20±10 microm. Compared with transistor devices, fabricated using conventional photolithographic methods and the same semiconducting material, this technique is a hopeful approach to produce microelectronic structures that are low-cost and all-organic.}, language = {en} } @misc{RiessSchmeisser, author = {Riess, W. and Schmeißer, Dieter}, title = {Organic Materials for Device Applications - Preface}, series = {Synthetic Metals}, volume = {138}, journal = {Synthetic Metals}, number = {1-2}, issn = {0379-6779}, pages = {S. 1}, language = {en} } @misc{SchmeisserPresselYamamotoetal., author = {Schmeißer, Dieter and Pressel, Klaus and Yamamoto, Yuji and Tillack, Bernd and Kr{\"u}ger, D.}, title = {Ge instabilities near interfaces in Si-SiGe-Si heterostructures}, series = {Materials Science \& Engineering B}, volume = {101}, journal = {Materials Science \& Engineering B}, number = {1-3}, issn = {0921-5107}, pages = {208 -- 211}, abstract = {Compositional characterization of interfaces in Si-cap/SixGe1-x/Si heterostructures is an important topic in SiGe based advanced microelectronics and in quantum wells. Extremely high depth resolution is required to detect and optimize near-interface compositional gradients which are crucial for high circuit performance. We report on non-destructive, high-resolution, near-interface depth profiling using SR photoelectron spectroscopy at an undulator beamline. We measured the Ge content at the SixGe1-x interface towards the native SiO2 layer and investigated the influence of additional (1nm and 2nm) Si capping layers (Si-cap). For the uncapped samples we found near the oxide/ SiGe interface region a strong mixing of Ge-oxides and SiOx. This indicates a high instability of the Ge atoms at those interfaces while silicon capped (1nm, 2nm) SixGe1-x films are more stable. We detect sharp Ge concentration gradients within the first 1nm at the Si/SixGe1-x interface. These results open new possibilities for Ge profile optimization in Si-cap/SixGe1-x/Si heterostructures. In the Ge3d spectra we differentiate the Ge atoms to occupy three different lattice sites and are able to follow their relative occupation within the Ge gradient.}, language = {en} } @misc{SchmeisserMuessig, author = {Schmeißer, Dieter and M{\"u}ssig, Hans-Joachim}, title = {The Pr2O3 / Si (001) interface studied by synchrotron radiation photo-electron spectroscopy}, series = {Solid State Electronics}, volume = {47}, journal = {Solid State Electronics}, number = {10}, issn = {0038-1101}, pages = {1607 -- 1611}, abstract = {Pr2O3 is currently under consideration as a potential replacement for SiO2 as the gate-dielectric material for sub-0.1micro m complementary metal-oxide-semiconductor (CMOS) technology. We studied the Pr2O3/Si(0 0 1) interface by a non-destructive depth profiling using synchrotron radiation photoelectron spectroscopy. Our data suggests that there is no silicide formation at the interface. Based on reported results, a chemical reactive interface exists, consisting of a mixed Si-Pr oxide such as (Pr2O3)x(SiO2)1?x, i.e. as a silicate phase with variable silicon content. This pseudo-binary alloy at the interface offers large flexibility toward successful integration of Pr2O3 into future CMOS technologies.}, language = {en} } @misc{SchmeisserIrmscherWagner, author = {Schmeißer, Dieter and Irmscher, Klaus and Wagner, Gerd}, title = {Photoelectron spectra of Al dopants in 4H-SiC}, series = {Materials Science \& Engineering B}, volume = {102}, journal = {Materials Science \& Engineering B}, number = {1-3}, issn = {0921-5107}, pages = {284 -- 288}, abstract = {Al-doped 4H-SiC epitaxial layers were grown in a hot-wall chemical vapor deposition (CVD) system on commercial 4H-SiC substrates (CREE). The incorporation of Aluminum has been studied in the concentration range from 2*1014cm-3 up to 3*1020cm-3. Epitaxial layers with doping concentration NA-ND> 1019cm-3 were studied by HV-TEM and synchrotron radiation investigations. In the concentration range from 1*1019cm-3 to 3*1020 cm-3, measured by SIMS and Hall investigations, no Aluminum precipitation were detected in the grown layers. For SiC samples with an Al concentration of 1020cm-3 we have been able to detect the Al2p photoemission signal. The Al2p signal is recorded through the oxide layer (thickness of about 0.4nm), it has a main contribution at a binding energy of 73eV which corresponds to the energy typical for elemental Al0. In spectra excited with higher photon energies the sampled photoelectrons originate from deeper layers. In these data we notice an additional shoulder in the Al2p signal at around 71eV. The evidence of two contributions is attributed to the fact that Al is incorporated at different lattice sites. As the latter data represent more bulk like properties we argue that Al in the bulk SiC occupies both, substitutional lattice sites and interstitial sites while in the surface near regions Al is found only at substitutional lattice sites.}, language = {en} } @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} }