Tailored Surfaces

Members of the Board of Trustees Freistaat Sachsen, Minister für Wissenschaft und Kunst vertreten durch Frau RD’in Cathrin Liebner Bundesrepublik Deutschland, Bundesminister für Bildung und Forschung vertreten durch Herrn MinR Dr.-Ing. Joachim P. Kloock Verein des Leibniz-Instituts für Oberflächenmodifizierung e. V. vertreten durch Prof. Dr. Konrad Samwer und Dr. Karsten Otte Members of the Scientific Advisory Board Prof. Dr. Roger Gläser (Chairman) Universität Leipzig Dr. Klaus-Friedrich Beckstette Carl-Zeiss Oberkochen Dr. Kurt Dietliker ETH Zürich and BASF Schweiz AG, Switzerland Prof. Dr.-Ing. Dr. h. c. Ralf Eckhardt Beyer Fraunhofer-Institut für Werkstoff- und Strahlentechnik und Technische Universität Dresden Prof. Dr. Marius Grundmann Universität Leipzig, Fakultät für Physik und Geowissenschaften PD Dr. Bernd Herzog BASF SE, Ludwigshafen a. R. Prof. Dr. Hans-Gerd Löhmannsröben Universität Potsdam Tino Petsch 3D-Micromac AG, Chemnitz Prof. Dr. Christina Trautmann GSI Darmstadt Prof. Dr. Karl-Michael Weitzel Philipps-Universität Marburg

Contents 7 Preface 15 Scientific and Technology Results 16 xx 16 20 24 28 32 36 40 44 43 42 44 45 46 47 48 49 50 51 52 Reports Development of plasma jet based process chains for optical free form machining Nanostructured TiO2 on a polymer membrane for water purification Modeling mechanical properties of surfaces, thin films and nanostructures across length scales Photo-induced electron dynamics on semiconductor surfaces probed by ultrafast photoelectron spectroscopy Properties of phase change material films deposited by pulsed laser deposition Radiation (EB and UV)-induced reduction of graphene oxide – a novel, highly efficient pathway to high quality bulk graphene Characterization of structural defects in epitaxial GaN thin films grown by IBA-MBE Selected Results Realization of surface gratings with sub-atomic height modulations Surface modification for the mass analysis of latent fingerprints Influence of ion current density during low energy nitriding processes Surface functionalized carbon materials in solid acid fuel cell electrodes Laser embossing – a non-thermal approach for 3D micro- and nanopatterning of copper Development of gas barrier films for applications together with graphene electrodes in OLEDs Electron beam assisted crosslinking and optimization of gelatin hydrogels NIR chemical imaging of coatings and laminates New neutralization concepts for electric propulsion thrusters 53 55 New Equipment for Research and Application 61 Personal Activities 62 63 64 Doctoral Theses Diploma and Master Theses Activities in Scientific Organisations 65 Honours and Awards 67 68 68 71 73 Scientific Events Scientific Meetings Institute Colloquia Lectures Seminars 75 Publications and Presentations 76 88 92 92 104 Publications in Journals and Books Conference Proceedings Presentations Talks Posters 110 112 Patents Imprint

PREFACE Preface The Leibniz Institute of Surface Modification (IOM) per- forms investigations in the field of modification of surfac- es and thin films by ion beam-, electron-, laser- and plasma techniques. It combines fundamental and applied research with the aim to explore interaction processes with materials and to establish such modified materials in economically relevant and forward-looking technology fields. The research activities include Ultra-precision smoothing and shaping by ion beam and plasma technologies Structuring of surfaces by laser beams and analysis of thin films Deposition of thin films and nanostructures by ion, laser and plasma technologies Modification of surfaces by electron and photon tech- nologies Development of nanocomposites and cross-linked polymer films Preparation of bio-functional films and modification of membranes This biennial report 2014 / 2015 presents some selected scientific contributions, a general overview of the scien- tific life and compilations of the published results, talks and patents. Particular highlights in 2014 and 2015 were: In year 2014 the IOM started with a new series of colloquia, the Gustav-Hertz colloquia. Renowned scientists will report about the progress in selected research fields. The first lecturer was Peter Sigmund, professor at the Southern Danish University Odense and one of the best known scientists in the field ion solid-interaction. One highlight was the inauguration of our new 10 MeV electron accelerator. In future this large research instru- ment should allow the solution of scientific problems and it will be open to other researchers. Another highlight in 2015, which will strongly influ- ence the institute future efforts in the field of the applica- tion of ion and plasma technologies, was the appointment of an endowed professorship in conjunction with the Technical University of Dresden. This endowed chair held by Prof. Dr. Th. Arnold is supported by industrial enter- prises and the Federal Ministry of Research and Technolo- gy. In the year 2014 the Leibniz joint lab “Single Ion Implantation” was founded by the Physical Department of the IOM and the Department of Nuclear Solid State Phys- ics of the University Leipzig with aim to develop a tech- nology for deterministic single ion implantation. This development is supported by the Leibniz Association and the European Union. The IOM was able to start with establishing an appli- cation center in the middle of the year 2015. The con- struction of this center and its equipment is supported by the European Union, the Federal Republic of Germany and the Free State of Saxony and will support the transfer of IOM technologies to the industry. In 2015, the evaluation process of the Leibniz Insti- tute of Surface Modification by the Leibniz Association was completed with great success. Accordingly, the Insti- tute will be able to continue its successful work. As a Leibniz Institute, the IOM receives its basic funding by the Free State Saxony and the German federal gov- ernment in equal parts. An important indicator of scien- tific quality at the IOM is the amount of additional third party funding, which in 2014 /2015 amounted to a total of 16 Mio Euro. This results in the IOM standing in the forefront of the Leibniz Association using this important criterion. The IOM is becoming more and more attractive for inter- national colleagues. In 2014 and 2015 scientists from USA, China, Japan, India, UK, Chile, Bulgaria, etc. choose to stay at the IOM. The number of the PhD and master students working at the IOM was significantly increased in the last two years to an average of about 40. These students are involved in all scientific projects and resulting publications. The train- ing of the students, doctoral candidates and young scien- tists remains a very important mission of the IOM. The IOM puts strong emphasis on collaboration with in- dustry, small and medium enterprises, universities and other research laboratories. The IOM also participates in joint projects directly funded by the industry or by pro- grams of Federal Ministry of Research and Technology or the Free State of Saxony. The successful cooperation with chemical, optical and semiconductor industry has been continued. The IOM would like to thank all partners and friends, and the Leibniz Association who supported its progress in 2014 and 2015. Special thanks are due to the Board of Trustees, the Scientific Advisory Board, the Ministry of Science and Arts of the Free State of Saxony, and the Ministry of Education and Research of the Federal Gov- ernment of Germany. Our partners from research insti- tutes, universities and industry all around the world con- tribute essentially to the success of the IOM and played a crucial role for its ongoing development. Last but not least, the director would like to thank the staff of the institute for their dedicated efforts and excellent contribu- tion in the last two years. Leipzig, in spring 2016 Prof. Dr. Dr. h. c. Bernd Rauschenbach Director

PREFACE APPOINTMENT OF AN ENDOWED PROFESSORSHIP / In 2015 Prof. Dr. Th. Arnold was appointed as endowed professorship in the field of the application of ion and plasma technologies in conjunction with the Technical University of Dresden and supported by industrial enterprises and the Federal Ministry of Research and Technology. LEIBNIZ JOINT LAB “SINGLE ION IMPLANTATION” / In 2014 the Leibniz Joint Lab “Single Ion Implantation” was founded by the Physical Department of the IOM and the Department of Nuclear Solid State Physics of the University Leipzig with aim to develop a technology for deterministic single ion implantation. This development is supported by the Leibniz Association and the European Union.

PREFACE AWARDS OF THE INSTITUTE / Science and Technology Award 2014 Dr. Jürgen Gerlach For his contribution to the topic “Interaction of low energy ions with solids” / Young Scientist Award 2014 Dr. Eric Thelander For his thesis with the title “Epitaxial Ge-Sb-Te thin films by pulsed laser deposition” / Science and Technology Award 2015 Dr. Ulrike Helmstedt For her contribution to the topic “Development of a new method for producing a rotative printing plate” / Young Scientist Award 2015 Dr. Kristina Fischer For her thesis with the title “Photocatalytical active membranes for the removal of pharmaceuticals from waste and surface waters”

Scientific and Technology Results Reports Selected Results

Reports of up to some 10 mm³/min can be achieved while low-rate plasma sources produce small spatially confined jets and material removal rates of 0.01 mm³/min or less. In order to perform a determinis- tic sub-aperture surface figuring process the plasma source is moved by a CNC motion system comprising 5 stages to drive the plasma jet over the surface. The motion scheme is determined by local dwell times calculated by numerical decon- volution algorithms. These algorithms are capable to take into account dynamic characteristics of the tool function during the machining process, e.g. changes in etching rate due to surface heating effects [2]. Plasma jet polishing A specially designed plasma jet source employing only Ar/He gas mixtures has been developed as a tool for polishing fused silica surfaces. For that purpose the inert gas plasma jet is employed forming a hot spot on the surface with tempera- tures of approx. 1800°C. As a result the viscosity of the fused silica in the hot region is significantly decreased while surface tension and capillary forces lead to redistribution of material. Similar to the figuring process, the plasma jet is guided over the surface by the motion system. Machining rates of up to 1 cm2/min have been obtained. The surface smoothing mechanisms are sup- posed to be similar to those occurring in flame (a) (b) Figure 1: (a) Mechanically polished surface after plasma jet etching, (b) plasma jet polished surface after plasma jet etching. (a) (b) Figure 2: (a) Half side plasma polished asphere (red ar- row), (b) roughness measurement of the polished surface. polishing or laser polishing [3]. It has been shown in previous investigations that HF wet etching or reactive plasma etching of fused silica lead to characteristic surface micro- roughness [4,5]. High spatial frequency structures occur in strong dependence on initial surface roughness, chemical contaminants, or sub- surface damage (SSD), since fluorine atom attack on the surface is highly selective. Thus, etching depth has a significant influence on the final mi- cro-roughness. Roughness evolution during plasma treatment has been investigated on differ- ently prepared fused silica samples. Figure 1 (a) shows an interference microscope image of a mechanically polished surface, which has been plasma etched to 30 µm depth. The occurring defect structure indicates the presence of SSD causing a final roughness of 25 nm RMS. In con- trast to this a roughness of <0.5 nm RMS is ob- tained when a thermal plasma polishing step is applied prior to the etching step on the same sur- face (see Figure 1 (b)). This value is sufficient for many optical applications. From the findings it can be concluded that plasma jet polishing is capable to heal micro-cracks buried in the near-surface region located below the Beilby layer [4]. Plasma polished fused silica surface is thus most suitable for subsequent plasma jet etching steps. A representative plasma jet polishing result is shown in Figure 2. One half of a fine ground as- pheric surface with roughness Sq~250 nm has been treated by the polishing jet, yielding a s sig- 17

Reports Figure 5: Residual figure errors (a) of ground asphere Ø50 mm, (b) after plasma jet polishing, (c) after plasma jet fine correc- tion. and efficient smoothing and figure error correction is required. As an example a ground convex as- phere (diameter 50 mm) with surface figure error of 0.89 µm PV has been finished. Figure 5 illus- trates the chain consisting of the following steps: Freeform mechanical grinding process (i) ending up with a fine ground surface quality with roughness Sq~250 nm and a figure error of typi- cally less than 1 µm PV. (ii) Plasma jet polishing: The surface is then thermally treated to decrease the roughness to a value of <1 nm RMS and SSD is removed while the figure error remains more or less unchanged. (iii) Plasma jet fine correction: This step is employed to diminish the figure error and keeping the roughness. The plasma polishing process lasted approx. 45 min. Form measurements indicate that the sur- face shape has barely altered from its initial value. Micro-roughness has been determined to be Sq=0.25 nm ±0.05nm over the entire surface. After approx. 30 min of plasma jet fine correction the shape has been significantly improved. Em- ploying this process chain can significantly save machining time compared to conventional optical machining since only two steps need to be ap- plied. The main advantage is the avoidance of abrasive slurries, elaborate workpiece cleaning between machining and measurement steps, or the utilization of expensive and slow IBF process- es. Thus, this chain has the potential to greatly increase the manufacturing efficiency as far as the preform can be manufactured by precision freeform grinding. Conclusion The characteristics of PJM have been discussed and two processing chains for asphere and freeform manufacturing have been introduced that comprise plasma jet polishing, plasma jet high- rate figuring and correction, as well as auxiliary sub-aperture polishing steps. Both chains provide the opportunity for precise fabrication of optical elements with difficult surface shape like non- standard aspheres, acylinders or freeforms. In contrast to the conventional grinding and polishing techniques the non-contact PJM technology has nearly no geometrical limits. Furthermore, due to the pure chemical removal mechanism no sub- surface damage the amount of polishing removal after PJM is reduced to a few microns and hence, shape alteration during the mechanical polishing process is mini- mized. Employing the second process chain pure- ly based on plasma methods allows omitting any mechanical sub-aperture polishing avoiding the problems and challenges connected therewith. induced. Therefore, is Literature [1] Th. Arnold, G. Böhm, H. Paetzelt, Contrib. Plasma Phys. [2] J. Meister, Th. Arnold, Plasma Chem. Plasma Process 54 (2014) 145. 31 (2011) 91. [3] P. Cormont, P. Combis, L. Gallais, C. Hecquet, L. La- maignère, J. L. Rullier, Optics Express 21 (2013) 28272. [4] Q. Xin, N. Li, J. Wang, B. Wang, G. Li, F. Ding, H. Jin, Appl. Surf. Sci. 341 (2015) 142. [5] Z. Zheng, X. Zu, X. Jiang, X. Xiang, J. Huang, X. Zhou, C. Li, W. Zheng, L. Li, Optics & Laser Technology 44 (2012) 1039. 19

Reports ized water for up to 1 h (vapor-thermal). For the vapor-thermal method the water was added to a small glass beaker inside the Teflon flask to avoid contact of the TiO2 with liquid water. The Teflon flask was closed, placed in a high pressure pro- tective shell (DM00059) and sealed in a rotor segment (HPR-1000/10S with APCU-100). The morphology was characterized using a field emission scanning electron microscope (FESEM; Zeiss Ultra 55). The X-ray diffraction (XRD) was always measured with TiO2 nanotubes assembled on Si wafers or on TiO2 powder. The XRD pat- terns were observed on an Ultima IV X-ray diffrac- tion spectrometer (Rigaku) with Cu Kα radiation and operated at 40 kV and 40 mA with a scanning speed of 1° min-1 at a step size of 0.01°. X-ray photoelectron spectroscopy (XPS) was performed on Axis Ultra (Kratos Analytical Ltd.) with mono- chromatic Al Kα cathode, an X-ray source with 150 W power and 40 eV pass energy. Light ab- sorption properties were measured with UV-vis diffuse reflectance spectrometer (Cary 5000, Ag- ilent), and spectralon was used as a reflectance standard. The photoactivity of the membranes were tested by degradation of methylene blue (10 µmol L-1 or 20 µmol L-1, 4 mL), diclofenac sodium salt (25 mg L-1 or 5 mg L-1, 4 mL) or ibu- profen sodium salt (100 mg L-1, 4 mL) in aqueous solution at room temperature. For the static exper- iment, the samples (cut to circles with d = 2.5 cm and a circular hole in the middle with d = 1 cm for spectrometric measurement) were placed in a 6- well plate (Thermo Fisher Scientific, Nunclon Del- ta Surface), and the solution was added. The well plate was shaken on a Titramax 100 (Heidolph Instruments GmbH & Co.KG) with 200 rpm in the dark for 30 min for complete adsorption to take place. The well plates were irradiated with a UV-A sunlamp (Heraus Original Hanau Suncare tanning tube 21/25 Slim, radiant flux density 7.6 mW cm-2) and periodically measured with an Infinite M2 UV- Vis spectrophotometer (Tecan Group Ltd) at 660 nm (methylene blue), 276 nm (diclofenac) or 230 nm (ibuprofen). In order to measure the ab- sorbance at 276 nm and 230 nm, 60 µL of the solution was transferred to a UV-light transparent well plate (UV-Star microplate, greiner bio one). The photolysis was always monitored in the refer- ence well and was subtracted from the photoca- talysis values afterwards. For repeated measure- ments the membranes were washed 3 times with water for 10 min after complete degradation. The cross-flow experiment was operated with a self- built setup. The membranes were cut into circles (47 mm diameter) and placed onto the sample holder of the cross-flow apparatus. Diclofenac solution (25 mg L-1 or 5 mg L-1, 80 mL) was added to the flask. First the system was operated for 30 min without UVA-light for complete dark ad- sorption to take place. The vacuum pump was set to 800 mbar and the membrane pump was start- ed. The solution circulated from the flask to the membrane and through the membrane back to the flask. The inflow of the membrane pump was regulated by monitoring the liquid overlap (ca. 1 cm) on the membrane with a laser. By turning on the UV-LED lamp (6 UV-LED arranged in a circle, 365 nm, 7.5 mW cm-2, LZ1_00U600, LedEngin Inc.) the photocatalytic degradation was started. The decline in absorption at 276 nm was measured periodically in the spectrometer by (25 mg L-1 diclofenac) or transferring 60 µL 350 µL (5 mg L-1 diclofenac) from the flask to a 96-well plate (UV-Star microplate, greiner bio one). The solution was transferred back to the flask after measuring the absorption. Results and Discussion An often detected problem, especially with ano- dization of thin titanium films, i.e., short time of anodization, is the generation of surface debris on top of the TiO2 nanotubes, due to the formation of Ti(OH)4 or/and TiO2 at the surface. By increasing the chemical dissolution through adjustment of the electrolyte solution, voltage, and/or temperature, open nanotubes can be formed. The ammonium fluoride yield was increased (constant water con- tent of 3 vol% and voltage of 15 V) and the sur- face debris disappeared with an ammonium fluo- ride content of 0.8 wt% (Figure 1). The TiO2 nanotubes were strongly attached to the membrane and did adopt its flexibility and stabil- ity. The TiO2 nanotubes did arrange in arrays around the membrane morphology. Perpendicular formation appears to be favored as the array breaks up at round shapes when a certain angle is reached. When increasing the voltage from 15 Figure 1: FESEM images of as-anodized TiO2 nanotube arrays on top of a PES membrane: top view (a, b); and cross-sectional view (c). 21

] % [ 0 c / c Reports 1. degradation 2. degradation 3. degradation 4. degradation 5. degradation 20 40 60 80 100 120 100 80 60 40 20 0 0 Figure 5: FESEM image of as-grown TiO2 nanoparticles on the PVDF hydrophilic membrane. In (a) the untreated mem- brane is shown. The pre-wetted membrane was dipped for (b) 30 s, (c) 1 min and (d) 10 min into the TTIP solution. (diameter of 10 to 60 nm) on the membrane sur- face. This was achieved by hydrolysis of TTIP (titanium tetraisopropoxide) to TiO2 directly at the surface of the membrane. The membranes were pre-wetted in water so that a layer of water sur- rounded the surface of the membrane before the membrane got into contact with TTIP (formation of TiO2 only at the surface). The particle size in- creased with sustained time in the TTIP solution (Figure 5). The TiO2 nanoparticles were crystal- lized to anatase with water in its vapor form at 110 °C. The detected amount of TiO2 on the membrane (via thermal gravimetric analysis) was below 1 %. Therefore, the membrane porosity and water permeation flux of the PVDF membranes did not change significantly. Only the porosity of the PES membrane decreased clearly due to the high content of TiO2 on the PES membrane after synthesis. The TiO2 nanoparticles were strongly attached to the membrane. Rinsing the membrane with water at high speed had only a minor effect on the TiO2 nanoparticles of the hydrophobic PVDF mem- brane. The surface of the hydrophobic PVDF membrane does not contain any functional groups to bind TiO2 to the surface. However, the TiO2 nanoparticles were still strongly fixed to the mem- brane, because the synthesis of TiO2 occurred on the surface of the membrane. The hydrophilic PES membrane contains functional groups (sul- fone groups and ether bonds) to strongly bind the TiO2 nanoparticles. The strong attachment of TiO2 nanoparticles to the hydrophilic PVDF membrane resulted from the coordination bond between hy- droxyl groups (carboxyl groups from the modifica- tion of the manufacturer) and Ti4+. The dye methylene blue and the anti-inflammatory drugs diclofenac and ibuprofen were tested to be degraded from water by the three membranes with attached TiO2 nanoparticles. The hydropho- bic TiO2 – PVDF membrane was not suitable to time [min] Figure 6: The degradation of methylene blue was tested for 5 times with the hydrophilic TiO2/PES membrane. degrade any molecule in water due to its hydro- phobic properties. The hydrophilic TiO2 – PVDF membrane and the hydrophilic TiO2 – PES mem- brane degraded all tested molecules with a high rate. The difference of degradation behavior might rely on their varying adsorption behavior for the different molecules. With a high adsorption rate, the molecules to be degraded are close to the surface of TiO2. Thus, the molecules will be de- graded rapidly leaving free spots behind where new molecules can be adsorbed. The reusability of this system was tested by de- grading methylene blue within five repeated cy- cles (Figure 6). The degradation did not vary in between the first and the fifth degradation cycle. An indirect proof for the stability of the membrane against an attack from OH• radicals was obtained. No TiO2 nanoparticle loss was observed in be- tween the cycles due to a possible oxidative at- tack and/or loss of binding to the membrane sur- face. Conclusion The assembly of high-surface area TiO2 nanostructures (nanoparticles, nanotubes, and nanoneedles) on microfiltration membranes has been successfully achieved to gain strongly bound TiO2 with a high photocatalytic activity in degrading pharmaceuticals from water and to decrease the toxicity. Literature [1] K. Fischer, R. Gläser, A. Schulze, Appl. Catal. B-Environ. [2] K. Fischer, M. Kuhnert, R. Glaser, A. Schulze, RSC Adv. [3] K. Fischer, M. Grimm, J. Meyers, C. Dietrich, R. Gläser, A. Schulze, J. Membr. Sci. 478 (2015) 49. 160-161 (2014) 456. 5 (2015) 16340. 23

Reports Therefore, we simulated ultra-thin films of varying thickness using two different materials (silicon and strontium titanate). Within the approach of contin- uum theory, the reduction of the elastic constants of a thin film caused by surface stresses as a function of its film thickness L can be described by Cijkl L( ) = Cijkl bulk + 2 dijkl L because the force which is acting on a volume element decreases with increasing film thickness. Within the DFT simulations we were able to re- produce this qualitative behavior especially in the diagonal elements of the elasticity tensor, while the non-diagonal elements showed pronounced variations (Fig. 2 and Fig. 3). However, large de- viations from the aforementioned law are only observed for the smallest film thicknesses (one lattice constant for silicon and three lattice con- stants for strontium titanate). These deviations are not properties of the single surface, but can be explained by interactions of both surfaces in the simulation cell. Figure 3: Elastic Constants Cyzyz and Cxyxy (top) for Si and Cxxxx and Czzzz for SrTiO3 (bottom). relevant implying From the DFT calculated surface elastic constants dijkl, we were able to derive a continuum model, where the surface elasticity is implemented by stacking identical layers with differing (reduced) elastic constants. Further FEM simulations using different tip radii and forces (leading to different contact radii) gave us an estimation of the contact radii elasticity surface contributions. A significant change for both materials scrutinized is observed already at a contact radius rc of 5 nm. From the simulation results we were able to devise an analytical model that describes the indentation modulus as a function of its contact radius assuming that each layer can be described by an effective indentation modulus Mi=Minf - c/ai. Here, c denotes the reduction coefficient, i the number of layers and a the thickness of each layer. Assuming further that the stress field increases linearly with the contact radius and that each layer contributes equally, we get the following expression for the indentation modulus as function of the number of contributing Figure 2: Elastic constants Cxxxx and Czzzz (top) and Cxxyy and Cxxzz (bottom) calculated for Si. 25

Reports Conclusion In the present work, a variety of computational tools were employed to study the mechanical behavior of surfaces and low dimensional ob- jects, including AFM tip apexes, ultrathin Si and strontium titanate films as well as GaN surface steps. Combining FEM modeling, ab initio tech- niques and MD simulations in a multiscale ap- proach, a thorough understanding of the elastic response could be achieved. The present results demonstrate the emergence of size and surface stress related effects and have been discussed with respect to their impact on CR-AFM experi- ments. This paves the way for future CR-AFM studies and lays the groundwork for an improved understanding of nanoscale elastic properties. Acknowledgments This project was funded in part by the Leibniz SAW award (Senatsausschuss-Wettbewerb). Literature [1] A.M. Jakob, J. Buchwald, B. Rauschenbach, S.G. Mayr, Nanoscale, 6 (2014) 6898 [2] J. Buchwald, S. G. Mayr, Nanotechnology 26 (2015) 125704 [3] J. Buchwald, M. Sarmanova, B. Rauschenbach, S.G. Mayr, J. Beilstein, Nanotechnol. 5 (2014) 2164 [4] U. Allenstein, S. Selle, M. Tadsen, C. Patzig, T. Höche, M. Zink, S.G. Mayr, ACS Appl. Mat. Interf. 11 (2015), 1533 [5] U. Allenstein, F. Szillat, A. Weidt, M. Zink, S.G. Mayr, J. Mat. Chem. B 2 (2014), 7739 [6] A. M. Jakob, Ph.D. Thesis, Faculty of Physics and Earth Sciences, University of Leipzig, 2014 [7] J. Buchwald, Ph.D. Thesis, Faculty of Physics and Earth Sciences, University of Leipzig, 2015 27 Figur 6: MD-simulation of the local indentation modulus with contact area AC=1.23 nm² on top and below the GaN step edge (top). FEM simulation of the indentation modulus (AC=1.23 nm2) on top and below the GaN step edge without consideration of surface stresses (bottom). The local indentation modulus is notably sensitive to local stresses, as the effective contact area is minimal. Therefore it shows good agreement with the stress fluctuations, decreasing at the bottom and on top of the step edge, while the FEM simu- lations show a clear dependence of the step height, and even an increase of the elastic con- stants at the bottom of the step (Fig. 6). From these results one can conclude that both effects cancel in the MD simulation of the flat punch indentation with larger radius at the bottom of the step. On top, an overlap of both effects is observed, the geometrical effect dominates the stress effect, which becomes manifested in the range, but also in the differences between differ- ent step heights.

Reports vantages of ZnO over TiO2, the efficiencies of ZnO based DSSCs do not even nearly reach those of TiO2. Femtosecond time-resolved studies on dye mole- cules on ZnO and TiO2 revealed significant differ- ences in the photoinduced dynamics [3,4]. In the case of TiO2, the transfer of the electron from the dye into the conduction band of TiO2 is completed within < 100 fs. In contrast to this, the electron transfer into the conduction band of ZnO takes about 10 - 100 ps. These experiments indicate that the reason for the difference in performance between TiO2 and ZnO - based DSSCs lays in the initial electron transfer step from the dye to the semiconductor. The physical explanation for the observed differences, however, remained a mat- ter of debate. Here, we present results from femtosecond time- resolved inner-shell photoelectron spectroscopy experiments in combination with a detailed theo- retical modeling. Our results strongly support the existence of a transient intermediate state located at the interface between the ZnO substrate and the N3 dye. This intermediate state is identified as the bottle neck for electron transfer from N3 to ZnO. Experiment This experiment investigated the photoinduced charge transfer from the Ruthenium-based dye complex (bis(isothiocyanato)bis(2,2'-bipyridyl-4,4'- dicarboxylato)-ruthenium(II), also called N3) to zinc oxide nanocrystals. The N3 dye is anchored to the ZnO surface via carboxylate moieties on the dye (Figure 2). In order to gain insight into the physical origin of the long electron transfer time from the dye to the conduction band of ZnO, we use the following experimental strategy: A Ruthenium (Ru) atom forms the center of the N3 dye, and absorption of light induces a metal-to-ligand charge transfer excitation within the dye and the transfer of the excited electron to the semiconductor. In this pro- cess, valence electron density is removed from the Ru center and migrates via the ligands to- wards the ZnO. This change in valence electronic structure has an effect on the core level electrons, in particular on their binding energies. Key is that the binding energy of core level electrons gradual- ly increases if valence electron density is removed from the corresponding atom. Thus, the shift in binding energy of the core level electrons corre- lates with the degree of charge separation. In Figure 2: Carboxylate moieties anchor the N3 dye to the surface of ZnO. The dye is composed of a Ruthenium atom and surrounding ligands. other words, the core level binding energy shift is a measure for the distance between the excited electron and its parent atom (here: Ru center). In our experimental approach, we measure shifts in core level binding energies at the relevant time delays of 500 fs and 1 ps after excitation of the dye molecule, in order to gain insight into the bot- tle neck of photoinduced electron transfer. In these experiments, an ultrashort laser pulse with a center wavelength of 535 nm electronically excites the Ruthenium dye complex. A time- delayed X-ray pulse centered at ~850 eV is used to record the inner shell photoelectron spectrum of the sample in the region of the Ru 3d3/2,5/2 core level lines. The measurements are performed at the Soft X-ray Materials Science (SXR) instrument of the Linac Coherent Light Source (LCLS) using <100 fs long X-ray pulses. Results and Discussion Figure 3 shows the photoelectron spectrum of the sample in the region of the Ru 3d core levels. The signal of the Ru 3d5/2 level is separated from the other signals in the spectrum: The overlapping signals of the Ru 3d3/2 level and the C1s levels. Upon excitation of the sample with the pump- pulse (535 n), it is expected that a small fraction (corresponding to the small fraction of excited dye molecules in the sample) of both Ru 3d signals shifts to higher binding energies. The inset in the upper right corner of Figure 4 illustrates the ob- 29

Reports Conclusion We present time-resolved X-ray photoelectron spectroscopy (TRXPS) as a new tool to investi- gate ultrafast charge transfer processes on sur- faces. Experimental findings on the N3@ZnO system are interpreted with the aid of ab-initio calculations using constrained density functional theory and reveal an interfacial charge-transfer state, which precedes free charge carrier for- mation. This transient electronic configuration limits the efficiency of ZnO based dye-sensitized solar cells (DSSCs). Literature [1] K. R. Siefermann, C. D. Pemmaraju, S. Neppl, A. Shav- orskiy, A. A. Cordones, J. Vura-Weis, D. S. Slaughter, F. P. Sturm, F. Weise, H. Bluhm, M. L. Strader, H. Cho, M.- F. Lin, C. Bacellar, C. Khurmi, J. Guo, G. Coslovich, J. S. Robinson, R. A. Kaindl, R. W. Schoenlein, A. Belkacem, D. M. Neumark, S. R. Leone, D. Nordlund, H. Ogasawa- ra, O. Krupin, J. J. Turner, W. F. Schlotter, M. R. Holmes, M. Messerschmidt, M. P. Minitti, S. Gul, J. Z. Zhang, N. Huse, D. Prendergast, O. Gessner, J. Phys. Chem. Lett. 5, (2014) 2753. [2] A. Shavorskiy, S. Neppl, D. S. Slaughter, J. P. Cryan, K. R. Siefermann, F. Weise, M.-F. Lin, C. Bacellar, M. P. Ziemkiewicz, I. Zegkinoglou, M. W. Fraund, C. Khurmi, M. P. Hertlein, T. W. Wright, N. Huse, R. W. Schoenlein, T. Tyliszczak, G. Coslovich, J. Robinson, R. A. Kaindl, B. S. Rude, A. Ölsner, S. Mähl, H. Bluhm, O. Gessner, Rev. Sci. Instrum. 85, (2014) 093102. [3] C. Strothkämper, A. Bartelt, P. Sippel, T. Hannappel, R. Schütz, R. Eichberger, J. Phys. Chem. C 117, (2013) 17901. [4] H. Nemec, J. Rochford, O. Taratula, E. Galoppini, P. Kuzel, T. Polivka, A. Yartsev, V. Sundström, Phys. Rev. Lett 104, (2010) 197401. [5] B. E. Van Kuiken, N. Huse, H. Cho, M. L. Strader, M. S. Lynch, R. W. Schoenlein, M. Khalil, J. Phys. Chem. Lett. 3, (2012) 1695. Figure 5: The upper part of Figure 5 shows the three limiting cases of possible transient electronic configurations. The lower part of Figure 5 displays the chemical shift of the Ru 3d lines computed with different functionals. Figure adapted from Ref. [1]. measured at both time delays, 500 fs and 1 ps, indicates that the interfacial CT state has a life- time significantly beyond 1 ps. This is in agree- ment with previous experimental findings. [3,4] In the light of these new findings, the interfacial charge transfer state very likely contributes to the weak performance of ZnO based dye-sensitized solar cells: Following excitation of the dye by light, the excited electron transfers into an interfacial CT state between the dye and the ZnO. Comple- mentary experimental studies find that the elec- tron transfer into the conduction band of ZnO takes about 10 - 100 ps from the point of optical excitation of the dye [3,4]. According to these results the electron remains in the CT state for as long as 10 to 100 ps, before it eventually transfers into the conduction band of ZnO. While the elec- tron is in the CT state, its proximity to the corre- sponding hole on the dye make a recombination likely. Accordingly, this recombination seems to be a significant loss process in ZnO based dye- sensitized solar cells. We note that this loss process is less prominent in TiO2 based cells, because electrons directly trans- fer from the dye into the conduction band of TiO2 [3,4]. This explains the difference in performance between ZnO and TiO2 based dye-sensitized solar cells. It further highlights that the efficiency of ZnO based cells may be enhanced via a sur- face modification of the ZnO nanocrystals, which prevents the formation of interfacial charge trans- fer states. 31

deposition chamber through a quartz window at a 60° normal incidence with the target. Behind the window, a gate valve has been placed, which makes it possible to separate the laser entry win- dow and the deposition chamber. This enables the inevitable removal and cleaning of the laser entry window without breaking the vacuum in the main chamber. With this setup a regular base pressure of 4·10-8 mbar is maintained. The laser beam is projected on the target surface with a plano-convex lens (f≈800 mm) which resides on a slide. In that way the laser fluence on the target can be adjusted. Inside the chamber a target car- rousel is used which can hold three different abla- tion targets, simultaneously. The substrate holder is mounted perpendicularly to the target manipula- tor with a spacing of roughly 6.5 cm. Moreover, it is possible to move the substrate manipulator laterally to find the best deposition position. Inside the substrate holder a resistive heater is placed which enables substrate heater temperatures of up to 1100°C. Three different substrate types were used for the deposition of epitaxial GST films, namely freshly cleaved KCl(100) and BaF2(111) as well as chemically pre-treated Si(111). Amorphous GeTe films for the crystalliza- tion studies in the second part of this report were deposited on Si(100) substrates at room tempera- ture. The films were mainly characterized by x-ray dif- fraction (XRD), atomic force microscopy (AFM), transmission electron microscopy (TEM), UV-Vis spectrophotometry, differential scanning calori- metry (DSC) and electrical resistivity measure- ments. Epitaxial Growth of GST films by PLD GST films of higher crystalline quality can be achieved, when the film growth is either highly textured or even epitaxial using a suitable single crystal substrate. First, PLD was employed to deposit epitaxial Ge2Sb2Te5 layers on (100) ori- ented KCl-substrates [1]. XRD measurements showed a process temperature window for epitax- ial growth of the cubic GST phase between 200 and 300°C. Below 250°C (111) oriented GST dominated the growth process and above 250°C the (100) orientation was the dominating one. XRD pole figure measurements confirmed these results and additionally revealed that the (111) orientation consists of four domains with 90° azi- muthal separation with an initial 15° rotation with the substrate lattice, i.e., GST[2-1-1] || KCl[100]. Reports The (100) orientation grew cube-on-cube with KCl. A systematic variation of the deposition rate showed that it is possible to obtain epitaxial films in the range between 2.5 and 250 nm/min with no significant deterioration of crystal quality. A smooth topography of (111) oriented films was found, whereas the (100) dominated films is char- acterized by a higher surface roughness as evi- denced from AFM investigations. Second, PLD was also employed to deposit epi- taxial Ge2Sb2Te5 layers on the (111) plane of BaF2 single crystal substrates [2]. XRD measure- ments in this case exhibited a process tempera- ture window for epitaxial growth between 85 and 295°C (Fig. 2). No crystalline growth was ob- served for lower temperatures, whereas higher temperatures lead to strong desorption of the film constituents. The films were of hexagonal struc- ture with lattice parameters consistent with exist- ing models. x-ray pole figure measurements re- vealed that the films grew with one single out-of- plane crystal orientation, but rotational twin do- mains were also present (Fig. 3). The out-of-plane epitaxial to be Ge2Sb2Te5(0001) || BaF2(111), whereas the in- plane relationship was characterized by two direc- tions, i.e., Ge2Sb2Te5[-12-10] || BaF2[1-10] and Ge2Sb2Te5[1-210] || BaF2[1-10]. As the knowledge about the atomic structure and vacancy distribu- tion in phase change material films is of foremost importance in order to understand the underlying mechanism of fast reversible phase transfor- mation, state-of-the-art aberration- corrected high- resolution scanning transmission electron micros- copy (STEM) combined with image simulations was used to resolve the local atomic structure of PLD-deposited Ge2Sb2Te5 thin films and their relationship was determined Figure 2: XRD patterns of GST films deposited on BaF2(111) substrates at different temperatures. Hexagonal phase re- flections belonging to the GST225 phase are marked with black and those belonging to the GST124 phase are marked with blue. Substrate contributions are annotated in red. 33

tween the amorphous and crystalline state was measured. A simple model was used that allowed the discussion of the results based on the distribu- tion of the temperature over the sample upon laser irradiation in dependency on the laser flu- ence. Crystallization kinetics of GeTe phase- change thin films grown by PLD For the investigation of the crystallization process of phase change materials, PLD grown GeTe thin films on Si substrates were thermally treated [5]. XRD measurements revealed that the critical crystallization temperature lies between 220 and 240°C. DSC was used to investigate the crystalli- zation kinetics of the as-deposited films. The acti- vation energy for crystallization was determined to be 3.14 eV (Fig. 5). Optical reflectivity and in situ resistance measurements exhibited a high optical reflectivity contrast of ~21% (Fig. 6) and three to four orders of magnitude drop in the electrical resistivity of the films upon crystallization. Figure 5: (a) DSC diagrams of GeTe films recorded at differ- ent heating rates. (b) Kissinger plot for the determination of the activation energy of crystallization Ea. Reports Figure 6: Reflectivity contrast between annealed and as- deposited films at a wavelength of 650 nm. The dashed line is only intended as a guide for the eye. Conclusions The presented results generally demonstrate that phase change material films of the system Ge-Sb- Tb deposited by PLD exhibit the expected struc- tural, optical and electric properties. Epitaxial growth of GST films with high crystalline quality was realized on KCl(100), BaF2(111) and Si(111) surfaces. One particular advantage of the PLD method in this respect is the achievement of high deposition rates in comparison to MBE growth. GeTe films by PLD, crystallized upon laser pulse treatment as well as thermal treatment, show optical and electric switching properties that com- pare well with the properties of films which were deposited by conventional methods. Thus, the results on the crystallization of PLD-deposited GeTe films demonstrate that such films are a promising candidate for relevant phase-change applications Acknowledgements Parts of this work have been supported by the Leipzig School of Natural Sciences BuildMoNa (Grant No. GS 185/1) as well as by the European Union and the Free State of Saxony (LenA pro- ject; project no. 100074065). Literature [1] E. Thelander, J.W. Gerlach, U. Ross. F. Frost, B. Rau- schenbach, J. Appl. Phys. 115 (2014) 213504. [2] E. Thelander, J.W. Gerlach, U. Ross, A. Lotnyk, B. Rau- schenbach, Appl. Phys. Lett. 105 (2014) 221908. [3] U. Ross, A. Lotnyk, E. Thelander, B. Rauschenbach, Appl. Phys. Lett. 104 (2014) 121904. [4] X. Sun, E. Thelander, P. Lorenz, J.W. Gerlach, U. Decker, B. Rauschenbach, J. Appl. Phys. 116 (2014) 133501. [5] X. Sun, E. Thelander, J.W. Gerlach, U. Decker, B. Rau- schenbach, J. Phys. D Appl. Phys. 48 (2015) 295304. . 35

Reports ly seven orders of magnitude compared to starting materials. CT-GO ai-GO conductivity S × m–1 C/O conductivity S × m–1 no treatment hydrazine EB Indirect UV 5×10–4 a) 400 480 520 2.3 6.9 7.4 8.4 5×10–4 a) 4900 5400 5500 C/O 2.3 7.1 10.9 8.4 Table 1: Conductivity values and C/O ratios for reduced CT-GO and reduced ai-GO films obtained by different treatments of GO aqueous dispersions. a) - adopted from Langmuir 28 (2012) 8224. Figure 2: Change of the optical absorption for a nitrogen saturated aqueous dispersion of GO (0.05 g/l, 0.35 wt.-% of acetone and 2 wt.-% of 2-PrOH at natural pH 5) under illumination at 222 nm from 0 to 10 min photoirradiation time. Inset change of the optical absorption at 400 nm upon photoirradiation time. latter wavelength. A comparison of reaction times for GO-solutions containing none, one component or both is shown in Fig 3. A detailed discussion of the different mechanisms is presented in [4]. De- oxygenation of GO in the EB- and UV-systems is clearly confirmed by the results of XPS: a drastic decrease of O/C atomic ratios was observed, at a level comparable with the best chemical reduct- ants as hydrazine, vitamin C, respectively. High- resolution C1s XPS spectra (Fig. 4) clearly con- firm that the remaining carbon-oxygen bonds after reduction are attributed to carboxyl and carbonyl groups. Bright-field TEM measurements (see Fig. 5) con- firm a relatively flat appearance with typical wrin- kles and a double-layer structure and allow to conclude that the use of high energetic EB and indirect UV reduction does not lead to any signifi- cant structural worsening of the rGO flakes. [2] The conductivities of the rGO samples obtained by the EB, UV or hydrazine methods are similar. They all result in an improvement of approximate- Figure 4: High-resolution C1s XPS spectra for unreduced CT-GO (a) and reduced GO (rGO) obtained by hydrazine (b), EB- (c) and indirect UV-reduction (d). Figure 3: Reaction times observed for the photochemical reduction of GO in water. No additive (black); 2% 2-PrOH (blue); 1% acetone (green); 1% acetone and 2% 2-PrOH (cyan); 1% acetone and 2% 2-PrOH (red). Irradiation wavelengths and times are given in the figure. Figure 5: TEM images of rGO (a). SAED pattern (b) was taken from the area marked by the white circles in image (a). All measurements were done with CT-GO samples. 37

In case of the indirect photochemical reduction of GO α-hydroxyalkyl radicals of 2-PrOH are pro- duced by the following mechanism: acetone exci- tation leads to the formation of triplet acetone (3), which will react with 2-PrOH to give two reducing 2-PrOH radicals (4). Finally, GO is reduced by the electron transfer from 2-PrOH radicals (5) and the process is accompanied by deoxygenation (6). Conclusion We highlighted a rational synthesis strategy, ap- preciating the advantages of high energy radiation to provide optimal reduction conditions, which appears to be superior to other approaches lack- ing options in terms of environmentally friendli- ness, cost-effectiveness, and up-scaling for a high quality graphene material. It can be expected that both, EB-induced reduction or indirect photore- duction of GO will be a solid basis for the devel- opment of large scale production of rGO, because of the high efficiency, environmental compatibility and low costs. Thus, the production of superca- pacitors and other applications may benefit from the indirect photochemical reduction method. Experimental Section All chemicals were of analytical grade, bought from commercial vendors and used as received. Different GO samples have been investigated: a) single-layered GO purchased from Chea- tubes.com (USA; called CT-GO); b) home-made almost-intact carbon framework oxo-GO (ai-GO) synthesized by Eigler (details see [4]) and c) GO from Nanoinnova Technologies (Madrid, Spain, called NI-GO). Solutions were always freshly prepared in Milli- pore water (R > 18.2 MΩ) shortly before irradia- tion. For more details see [1,2]. The photoreduction of aqueous GO dispersions were conducted in a closed quartz cell (3 ml, irra- diated surface 3 cm2). Commercial UV lamps (Radium: 222 nm (6.4 mW/cm2) and Philips PL-S Reports 9W/ TUV 254 nm (16 mW/cm2) with photon fluxes of 1.2×10–8 or 3.4×10–8 Einstein/(cm2×s), respec- tively were employed. For the preparative irradiation of GO systems 10 MeV linear accelerators were employed (EL- EKTRONIKA, Toriy, Moscow and MB10-30MP, Mevex, Canada). For the kinetic studies the sam- ples were irradiated with high energy electron pulses (1 MeV, 15 ns duration) by a pulse trans- former type electron accelerator (Elit - Institute of Nuclear Physics, Novosibirsk, Russia). Changes of the optical spectra of the GO solu- tions were followed using a TIDAS-II UV-VIS spectrometer (Spectralytics GmbH, Essingen, Germany). Raman spectra were recorded from 1050 to 3410 cm-1 with a LabRAM ARAMIS (HORIBA Jobin Yvon) confocal microscope at 532 nm (2.33 eV) excitation wavelength from dip coat- ed silicon-oxide (300 nm) wafer. XPS spectra were recorded on Axis Ultra (Kratos, Manchester, UK) using monochromatized Al-Kα -radiation. Conductivity measurements were done on a four- point probe from Materials Development Corpora- tion (Chatsworth, CA). Acknowledgments The financial support of the European Union and the Free State of Saxony (LenA project) is greatly acknowledged. AK, BA are gratefully acknowledg- ing funding from the Deutsche Forschungsge- meinschaft (DFG) via grants KA 3491/2-1/AB 63/14-1 and EI 938/3-1. This work is also sup- ported by the Cluster of Excellence ‘Engineering of Advanced Materials (EAM)’, SFB 953 funded by the DFG and by “Nanotrace” (03X0130) funded by the Bundesministerium für Bildung und For- schung (BMBF). Literature [1] R. Flyunt, W. Knolle, A. Kahnt, A. Prager, A. Lotnyk, J. Malig, D. Guldi, B. Abel, Int. J. Radiat Biol. 90 (2014) 486. [2] R. Flyunt, W. Knolle, A. Kahnt, S. Eigler, A. Lotnyk, T. Häupl, A. Prager, D. Guldi, B. Abel, Amer. J. Nano Res. Appl. 2 (2014) 9. [3] R. Flyunt, W. Knolle, B. Abel, B. Rauschenbach, Patent, DE 10 2012 024 329.4 (2013). [4] R. Flyunt, W. Knolle, A. Kahnt, C. Halbig, A. Lotnyk, T. Häupl, A. Prager, S. Eigler, B. Abel, Nanoscale (2016) accepted. [5] A. Kahnt, R. Flyunt, C. Laube, W. Knolle, S. Eigler, R. Hermann, S. Naumov, B. Abel, Nanoscale 7 (2015) 19432. 39

ions·cm-2 ·s-1 during trogen ions by a hollow anode ion source. The ion source highly efficiently ionizes the passing N2 gas in a constricted DC glow discharge, resulting in N+ and N2+ ions accelerated towards the sam- ple surface. These ions have a maximum kinetic energy of 25 eV, which is low enough to avoid point defect creation below the surface as well as sputter processes at the sample surface. The nitrogen ion flux was constant at a value of 1.6×1014 the deposition whereas a Ga flux was 1.2×1014 atoms·cm-2 ·s-1. For the results presented in this paper samples were produced with the same growth conditions but different deposition times of 32 minutes (sam- ple A) and 150 minutes (sample B). Eventually, in order to saturate surplus Ga atoms, accumulating at the film surface in form of small Ga droplets during the growth process, a post-ion beam nitri- dation step with closed Ga source shutter was performed, until the RHEED pattern yielded high- est intensity indicating accomplished saturation. The electron beam was in the [2-1-10] azimuth of hexagonal GaN and of the SiC substrate. TEM specimen preparation is essential for atomic- resolution Cs-corrected STEM imaging. For STEM investigations, cross-sectional TEM speci- mens were prepared by a combination of focused high- and low-energy ion beam techniques [4]. Measurements of TEM specimen thickness were performed by electron energy loss spectroscopy. The TEM lamellae were oriented in [2-1-10] zone axis for hexagonal GaN (w-GaN) and 6H-SiC and in [01-1] zone axis for cubic GaN (z-GaN). STEM work was performed with a probe Cs-corrected TEM (Titan cubed G2 60-300) operated at 300 kV. By working in STEM mode with an accelera- tion voltage of 300 kV, a point resolution of 70 pm can be achieved. For imaging of light elements at the GaN-SiC interface, annular BF (ABF) method was used. Before STEM work, the TEM specimen was treated in a plasma cleaner for 10 min with a H2/O2 plasma recipe. All STEM images were slightly digitally filtered by a Wiener filter for noise reduction. Annular ranges of 79.5-200 mrad for the HAADF detector, 19-106 mrad for the ADF detector and of 10-19 mrad for the ABF detector were used. A probe forming aperture of 25 mrad was used in the HAADF and ADF experiments, whereas the aperture of 20 mrad was applied for imaging of light elements with the ABF detector. Image simulations were performed with the xHREM/xSTEM software package, based on the Fast Fourier Transform (FFT) multislice algorithm. Reports Results and Discussion An atomic-resolution ADF-STEM image of sample A is given in Fig. 1. The details of the three re- gions are clearly seen in the image. The presence of two different GaN polytypes, cubic and hexag- onal, is visible and was also confirmed by FFT analysis (insets in Fig. 1). The first nanometers of the GaN film (region3) consist of the w-GaN phase, followed by several nanometers of z-GaN (region2). Above the z-GaN layer, exclusively w- GaN is present in Fig. 1 (region1). This stacking sequence of the different regions consisting of w- GaN, z-GaN and w-GaN layers was observed within all the investigated TEM specimens. Only the thickness of the different GaN regions differs slightly. A similar microstructure was observed for sample B (film thickness 240 nm). However, some parts of sample B show the presence of only re- gion1 consisting of w-GaN without region2 and region3. In addition, the sequence of region3 fol- lowed by the region2 without region1 was ob- served in some parts of the thinner sample A. A variety of defect types was found in the cubic and the hexagonal GaN domains close to the GaN-SiC interface (regions2 and 3). Most of them were identified as basal-plane stacking faults (SFs), grain and stacking mismatch boundaries (shown below). The w-GaN layer (region1) on top of the z-GaN layer (region2) shows a significantly lower density of defects than the w-GaN and z- GaN layers (region2 and region3) close to the interface. Only some rarely distributed basal- plane SFs and grain boundaries were found dur- ing the atomic-resolution STEM investigations. The RHEED patterns in Fig. 1, taken in situ during the film deposition, represent the evolution of the Figure 1: Atomic-resolution ADF-STEM image of sample A with representative FFT images. The STEM image shows z- GaN and w-GaN regions with various defect types and cor- responding RHEED patterns obtained in situ during different growth stages. 41

Reports Conclusion GaN thin films with different thicknesses were directly deposited by IBA-MBE on super-polished 6H-SiC(0001) substrates without using any buffer layers. The thin films were characterized in situ by RHEED and ex situ by Cs-corrected STEM. At the beginning of the film deposition, GaN grows as w- GaN for some nanometers and then changes to z- GaN for several nanometers. These areas show a number of defects which were investigated in detail by atomic-resolution Cs-corrected STEM. The defects were identified as stacking faults, domain and stacking mismatch boundaries. The occurrence of strain was identified at the grain boundaries. The w-GaN growing on top of the z- GaN layer shows only planar defects, such as stacking faults. Thus, due the hyperthermal ions a high crystalline quality of w-GaN can be achieved. The real structure of the GaN-SiC interface was investigated. The heavy and light atomic columns at the GaN-SiC interface were detected by ABF- STEM and the polarity of the GaN films was de- termined as Ga-polar. The presence of z-GaN in the grown thin films is not favoured because of different physical proper- ties of the polytypes like e.g. band gap. The re- sults of this work show, however, the potential to grow w-GaN on top of a z-GaN layer. Since the z- GaN is confined up to 60 nm, the growth of w- GaN thin films beyond this thickness with a high crystalline quality is possible by IBA-MBE. How- ever, the synthesis of single phase z-GaN thin films on 6H-SiC(0001) is an issue by this tech- nique. The use of other substrates with cubic structure should favour the growth of z-GaN by IBA-MBE and further work is needed. Acknowledgements The financial support of the European Union and the Free State of Saxony (LenA project; project no. 100074065) is greatly acknowledged. Literature [1] J.W. Gerlach, R. Schwertberger, D. Schrupp, B. Rau- schenbach, H. Neumann, M. Zeuner, Surf. Coat. Tech- nol. 128-129 (2000) 286. [2] L. Neumann, J.W. Gerlach, B. Rauschenbach, Thin Solid Films 520 (2012) 3936. [3] S. Sienz, J.W. Gerlach, T. Höche, A. Sidorenko, T. Ma- yerhöfer, G. Benndorf, B. Rauschenbach, J. Cryst. Growth 264 (2004) 184. [4] A. Lotnyk, D. Poppitz, U. Ross, J.W. Gerlach, F. Frost, S. Bernütz, E. Thelander, B. Rauschenbach, Microelectron. Reliab. 55 (2015) 2119. [5] D. Poppitz, A. Lotnyk, J.W. Gerlach, J. Lenzner, M. Grundmann, B. Rauschenbach, Micron 73 (2015) 43 Figure 4: Atomic-resolution ABF-STEM image of GaN-SiC interface. The inset shows a magnified image of the GaN- SiC interface. grain boundary. The latter was also formed during the island coalescence, resulting in the formation of SMB. An atomic-resolution ABF-STEM image of the GaN-SiC interface is displayed in Fig. 4. The im- age shows not only presence of heavy elements like Ga and Si. With this technique it was possible to resolve also light elements and to determine directly the polarity of the GaN film. The polarity was determined as Ga-polar at all locations of the here investigated samples and never changes during the film growth. This finding is in good agreement with previously reported experimental and theoretical data. Due to the advanced TEM specimen preparation method, it was possible to prepare the interface region of GaN and SiC very homogeneously. This gives the possibility to re- solve the sequence in the GaN structure within the first monolayers. The stacking sequence in the first three monolayers at the GaN-SiC inter- face is irregular. The sequence in GaN starts with SFs (see left part of Fig. 4). However, areas where w-GaN is directly formed on 6H-SiC were also observed (see right part of Fig. 4). After these three monolayers, the stacking sequence was w-GaN followed by z-GaN and then again by w-GaN. The epitaxial relationship between 6H-SiC and GaN film was determined from Fig. 4 as: 6H-SiC(0001) || w-GaN(0001) || z-GaN(111), 6H-SiC[2-1-10] || w-GaN[2-1-10] || z-GaN[01-1].

Selected Results Surface modification for the mass analysis of latent fingerprints C. Elsner, U. Decker, B. Abel Latent fingerprints (LFP) on surfaces are im- portant targets in forensic sciences. [1] In general, fingerprint analysis is associated with the auto- mated or manual superposition of topological level 1 and 2 features of the sample and a set within a data base. However, level 1 and 2 features are easily to reproduce by simple techniques. Thus, adding chemical analysis e.g. by mass spectrom- etry imaging (MSI) as a third dimension towards forensic investigations and combining them with the topological analysis of level 3 features may significantly reduce the error rate. Mass analysis of latent fingerprints has been already performed by DESI- and MALDI-TOF-MS. [2] The current state of art is the separation of overlapped LFP by their different chemical profile which facilitates automated data base screening. However, main drawbacks are the limited spatial resolution, MSI- time duration of a complete fingerprint, and the huge amount of generated mass data. Thus, the current investigations focused on the detection of skin pores with a diameter of about 100 micron as level 3 features and the analysis of secreted sweat components therein. In order to protect the fingerprint against loss of resolution by the appli- cation of a conventional spray coated matrix the deposition of a gold layer in the nanometer scale by a magnetron sputter coating process was used. During this process, the LFP become visible due to surface plasmon resonance (SPR) effects. Preliminary studies revealed that the surface of the carrier substrates significantly influence the quality of the obtained fingerprint images probably based on SPR. Best results were obtained by the application of a nano-structured gold-coated membrane. High resolution mass spectrometry of 1500 1000 500 ] . u . a [ y t i s n e t n i 0 370 Loratadin from the fingerprint O O CH3 N N Cl Loratadin from reference drug 375 380 m/z 385 390 Figure 2: Example for drug detection within a fingerpore print by MALDI-TOF-MS. Figure 3: Workflow for the rapid analysis of LFP. the developed LFP-samples enables the detection of pores within the fingerlines as “hot spots” for further chemical investigations (Figure 1). [3] Thus, drugs and their metabolites can be detected within the pores with few one-spot laser shots which may qualify the technique for a rapid non- invasive point-of-care diagnostic in the medical field (Figure 2). Combining rapid fingerprint development by sur- face coating techniques (1), iterative image pro- cessing and object analysis (2), and iterative spa- tial localized mass analysis (3) based on generat- ed data from step 2 an approach for the 3- dimensional analysis and reconstitution of finger- prints within a short timescale and a reduced data amount seems possible (Figure 3). Figure 1: Visualization of pores in LPF by MALDI-TOF-MSI. Literature [1] P. Hazarika, D. A. Russell, Angewandte Chemie- International Edition 51(2012) 3524. [2] D. R. Ifa, N. E. Manicke, A. L. Dill, G. Cooks, Science 321 (2008) 805. [3] C. Elsner, B. Abel, Scientific Reports 4 (2014) 6905. 45

Selected Results Surface functionalized carbon materials in solid acid fuel cell electrodes O. Naumov, B. Abel, A. Varga, A. Prager, P. Hertel The intermittency of renewable energy generation currently poses a major challenge for a secure energy supply. Electrochemical systems such as fuel cells will play an important role due to their high energy conversion efficiency, independent of size. However, precious metal catalysts are still necessary for most technologies to enable the electrochemical reactions at the electrode at a reasonable rate and much effort is spent on de- veloping and understanding carbon based materi- als to promote electrode reactions. [1] Beyond using carbon nanotubes (CNTs) as cata- lyst carriers [2], we utilize surface functionalized CNTs as precious metal free electrode compo- nents in solid acid fuel cells to enhance the oxy- gen electroreduction at the cathode. CNTs are directly synthesized via chemical vapor deposition (CVD) on carbon paper current collector sub- strates. Surface functionalization of the as syn- thesized CNTs is achieved with an oxygen or nitrogen plasma treatment, Figure 1. A significant increase in the surface concentration of oxygen is observed via X-ray photoelectron spectroscopy (XPS) and an increase in graphitization via RA- MAN spectroscopy. It is believed that through the plasma treatment, amorphous and defective car- bon structures are removed preferentially. AC impedance spectroscopy and cyclic voltam- metry was used to measure the electrochemical response of CNT electrodes. For this purpose, asymmetric cells (PtCsH2PO4CNT) were fabri- cated with a uniaxial cold-press. The measure- ments were completed in a humidified argon or oxygen environment at 240°C. At these condi- tions, one electrode serves to consume protons, arriving through the electrolyte, via the oxygen reduction reaction (ORR) while at the other elec- trode, protons are generated. This occurs via the electrochemical oxygen evolution reaction (OER) and/or carbon corrosion. Figure 1: SEM micrographs of CNTs grown on carbon paper current collector substrates via chemical vapor deposition a) before and after b) nitrogen and c) oxygen plasma treatment towards oxygen surface Figure 2: Cyclic voltammogram of a PtCsH2PO4CNT electrochemical cell in humidified Ar (green line) and O2 (blue line) at 240°C. Select, representative results are shown in Figure 2. The cyclic voltammogram of an asymmetric cell measured in humidified argon and oxygen shows clear differences for the two sweeping directions as expected and, more significantly, for the appli- cation of CNTs as active cathode components, higher currents when ORR is occurring on the CNT electrode. AC impedance spectra of sym- metric cells (not shown here) indicate a clear re- duction of the electrode impedance with plasma- treatment of the CNTs. Pre and post electrochem- ical measurement analysis of the material surfac- es points functional groups and/or a cleaning of the material surfaces from amorphous carbon as beneficial for electro- chemical activity. Based on the electrochemical data, we have strong indication that precious metal free CNTs enhance the electrode activity of solid acid fuel cell cathodes and that it can be tuned with surface functionalization methods, such as plasma treat- ment. Incorporation in 3-dimensional nanostruc- tures is expected to result in application relevant performances. [3] Literature [1] K. Gong, F. Du, Z. Xia, M. Durstock, L. Dai, Science, 323 [2] Á. Varga, M. Pfohl, N.A. Brunelli, M. Schreier, K.P. Giapis, [3] R.C. Suryaprakash, F. Lohmann, M. Wagner, B. Abel, A. S.M. Haile, Physical chemistry chemical physics : PCCP, 15 (2013) 15470. (2009) 760. Varga, RSC Adv., 4 (2014) 60429. 47

Selected Results Development of gas barrier films for applications together with graphene electrodes in OLEDs L. Prager, P.C. With, E. Bilz, R. Heller, U. Trimper (“Graphene Within the frame of the collaborative EU project GLADIATOR layers: Production, Characterization and Integration”, 7th Framework Programme) the working group Functional Layers has to develop flexible and transparent high- barrier foils which are suitable as substrates for organic light-emitting diode (OLED) stacks which contain thin high-conductive graphene layers in- stead of conventional indium tin oxide (ITO) thin films as transparent electrodes on the front side. For this aim, water vapour transmission rates (WVTR) of these foils has to be diminished below 10-4 g m-2 d-1. Moreover, surface properties have to be adapted to the surface properties of the graphene layer by reasons of trouble-free transfer onto the barrier foil surface as well as good adhe- sion during further technological steps and within the lifetime of completed OLED devices. High-barrier substrate foils developed at IOM consist of two laminated single-barrier films. In previous studies it was found that their barrier values could be dramatically improved by apply- ing a thin polysilazane (PHPS) derived silica layer on top of a silica pre-coating layer generated by a fast and efficient PVD process (CERAMIS® tech- nology, project partner AMCOR) [2]. For this, the PHPS conversion to silica [1] was conducted by VUV irradiation applying a roll-to-roll process de- veloped at the IOM [2]. By reasons of flexibility (demand 1000 bending cycles with a diameter of 1 cm) and optical trans- mission, it is important to minimize the thickness Figure 1: Barrier values of five various PVD pre-coatings before (big symbols) and after final coating by application of three different PHPS thicknesses on each pre-coating (small symbols). Figure 2: SEM image of a successful graphene transfer on top of a surface modified barrier film. of the resulting composite silica layer, preserving high-barrier properties. In this manner, experi- ments were carried out together with AMCOR to elucidate the influence of thickness variations of both the pre-coating and the PHPS-derived silica layer (Figure 1). The WVTR of single barrier PVD films could be improved between 1 and 2 orders of magnitude by an additional PHPS coating. Best results were obtained when both the pre-coating and the final silica layer were approx. 100 nm thick. Note that thicker layers did not result in improved barrier values but in more brittle films. For surface adaption of the barrier films to the graphene layers, several hydrophobic coatings (water contact angle CA = 90° - 100°) were ap- plied. For several surface modifications especially using alkyl- and phenyl- silazanes, alkylsilanes, acrylates and hexamethyl disilazane, a successful graphene transfer to the barrier foils was achieved (Figure 2). Literature [1] W. Knolle, L. Wennrich, S. Naumov, K. Czihal, L. Prager, D. Decker, M.R. Buchmeiser, Phys. Chem. Chem. Phys. 12 (2010) 2380. [2] L. Prager, U. Helmstedt, H. Herrnberger, O. Kahle, F. Kita, M. Münch, A. Pender, A. Prager, J.W. Gerlach, M. Stasiak, Thin Solid Films 570 (2014) 87. 49

Selected Results NIR chemical imaging of coatings and laminates T. Scherzer, G. Mirschel, O. Daikos, K. Heymann Spectral imaging provides the unique possibility to monitor quantitatively the spatial distribution of chemical and physical parameters as well as the homogeneity of the sample. In the past, it was ge- nerally carried out in a microscope, which allows only very small samples to be analyzed. However, the emergence of large hyperspectral cameras enables the continuous large-area scanning of materials and thus the introduction of chemical imaging into process control technology. For the investigation of the potential of this meth- od for applications in technical processes and the development of efficient quantitative monitoring procedures, a measurement station based on a near-infrared (NIR) camera mounted on a con- veyor was built up at IOM. The camera sensor (InGaAs) with 192 x 96 pixels (spatial x spectral resolution) covers a spectral range from 1320 to 1900 nm. NIR spectra can be recorded with a maximum frame rate of 795 Hz, which allows the scanning of large-area samples during the move- ment of the conveyor. Quantitative data are ob- tained by the use of powerful chemometric ap- proaches for the evaluation of the spectral data, and image processing methods are applied for the calculation of distribution patterns. In the framework of two public projects, the poten- tial of hyperspectral imaging for monitoring of coating and lamination processes was investigat- ed. In case of laminates, the thickness and the homogeneity of the hidden adhesive layers inside the laminates was in the focus of interest. The applied coating weight of the hot melt adhesive and its homogeneous distribution are essential for the performance of the laminate. Figure 1 shows an example of an inhomogeneity in a textile lami- nate to be used for interior design in the automo- Figure 2: Conversion in a 90 µm coating of an acrylate var- nish on glass after UV irradiation. Differences in conversion result from variations in the thickness of the layer. tive industry. NIR-based spectral imaging is the only technique suited for processes control that is able to characterize such layers that are not visi- ble from outside. It has been shown that even layers inside black laminates can be quantitatively analyzed. Moreover, the coating weight of such layers can be determined with a precision of about 4 g m-2. An important parameter in the UV curing of coat- ings is the conversion that is achieved during UV irradiation. NIR spectroscopy has already been shown in the past to be perfectly suited for contin- uous monitoring of the acrylate conversion in coating and printing processes [1]. However, us- ing a conventional process spectrometer, the con- version can be determined only in a small stripe corresponding to the spot size of the probe head. In contrast, NIR chemical imaging allows large- area analysis of the conversion. An example is shown in Figure 2. The differences in conversion result from variations in the thickness of the coat- ing and the gradient of the conversion. Other investigations carried out by hyperspectral imaging were directed towards the analysis of layers applied in wet-chemical finishing processes (e.g. on textiles), the detection of impurities and blots, the progress of drying processes, etc. Figure 1: Chemical image of a hot melt adhesive layer in a textile laminate. The lower right corner of the adhesive web was fold over. Literature [1] G. Mirschel, O. Daikos, K. Heymann, U. Decker, T. Scher- zer, C. Sommerer, B. Genest, C. Steckert, Progr. Org. Coat. 77 (2014), 1682. 51

New Equipment for Research and Application

Pilot-scale coating machine for advanced flexible gas-barrier films Development of cost-efficient flexible gas-barrier films for encapsulation of sensitive thin-film photovol- taics is currently a challenge facing industry when aiming on higher quota of renewable energy produc- tion. Recently, at IOM has been developed a photo- chemical process working at normal pressure and low temperature which consists of the UV initiated conversion of a thin polysilazane layer into silica. A pilot-scale coating machine has been designed and constructed with the aim to further develop gas- barrier films and their production technology. The machine enables scale-up to wider substrates, demonstrations in true technical scale, and resilient economical evaluation of the production process. System for deterministic single ion im- plantation Deterministic ion implantation, i.e. the implantation of a pre-defined, counted number of single ions with a lateral accuracy of a few nanometers, is a promising technique to realize a functionalization of single at- oms in a solid state material.In the framework of a mutual project, the Leibniz Joint-Lab “Single Ion Im- plantation” of the IOM and the Nuclear Solid State Physics Department of the University of Leipzig was equipped with an advanced high resolution focused ion beam system containing a high precision laser interferometer stage for accurate and reproducible sample positioning. This development system will be extended with a gas ion beam source together with a sophisticated single ion detector in order to fabricate quantum devices or sensors based on function- alized single atoms.

Reactive ion beam etching facility for sub- strates with 450 mm diameter Reactive i on beam etching (RIBE) is a sophisticat- ed technology enabling the fabrication of e.g. optical elements with sub-atomic precision. Within the extend- ed research infrastructure a new state-of-the-art RIBE facility was realized. The integrated 5 axis-motion sys- tem enables now a uniform etching of large workpieces with diameters up to 450 mm and a maximum weight of 50 kg. The RIBE system is equipped with Kaufman-type ion source, configured for Fluorine-based etching gas- es, and can be upgraded with different optical and masspectroscopic in-situ measurement technologies which guarantee a high process stability and reliability. With the RIBE 450 etching plant newly developed IOM etching processes for ultraprecise and innovative struc- tured functional surfaces can be further scaled up for industrial relevant sizes. NIR Laser workstation Laser microprocessing of bulk materials and thin films is a key technology for future industrial production processes. The new NIR laser workstation for micro material processing is equipped with two laser sources addressing the question of perfect wavelength and optimized pulse duration for specific laser material in- teractions. The 1.55 µm ns laser allows a larger pene- tration into semiconductor materials in order to study interface-related interaction mechanism. The pulse- shape-adjustable laser (λ = 1.06 µm) enables the opti- mization of thermal driven laser processes. In addition to the new physical capabilities the work- station allows to study processes at almost industrial conditions due to the build-in fast scanner and stage technologies enabling processing speeds up to 20 m/s.

Personal Activities Doctoral Theses Diploma and Master Theses Activities in Scientific Organisations Honours and Awards

Doctoral, Diploma and Master Theses Diploma and Master Theses 2014 Balmuri, Upender Rao Characterization of thin gallium nitride films deposited on polyimide substrates by ion-beam as- sisted deposition Hochschule Bremen, 2014 Glaß, Sarah NMR-spektroskopische Untersuchungen der Primärschritte der NNFGAIL-Aggregation Fakultät für Chemie und Mineralogie, 2014 Janke, Daniel Untersuchung der Eigenschaften von ionenstrahlunterstützt abgeschiedenen polykristallinen Galliumnitrid-Schichten auf flexiblen Polyimidsubstraten RWTH Aachen, 2014 Jorewitz, Marcel Kontrollierte cis-trans Isomerisierung in substituierten Azobenzolen Fakultät für Chemie und Mineralogie, 2014 2015 Baule, Nina Dotierung von Phasenwechselmaterialien mittels Ionenimplantation Ernst-Abbe-Hochschule Jena, Fachbereich SciTec, 2015 Bernütz, Sabine Characterization of laser irradiated Ge2Sb2Te5 films by atomic resolution Cs-corrected STEM Universität Leipzig, Fakultät für Physik und Geowissenschaften, 2015 Ganapaphti, Pradeep Synchronization of time proceeding axes: Laser pulses for spatially precise materials processing Hochschule Bremen, 2015 John, Thorsten A molecular dynamics study on alternative mechanisms of amyloid fibrils growth Fakultät für Chemie und Mineralogie, 2015 Oehmichen, Sarah Synthese und Charakterisierung photodynamisch-antibakterieller Cryogele Fakultät für Chemie und Mineralogie, 2015 Wagner, Maximilian Higher efficiency with lower platinum loading: A systematic study of nanoporous solid acid fuel cell electrodes Fakultät für Chemie und Mineralogie, 2015 63

Honours and Awards Honours and Awards Jürgen W. Gerlach Wissenschafts- und Technologiepreis des IOM Leipzig (Institutspreis) 2014 Ulrike Helmstedt Wissenschafts- und Technologiepreis des IOM Leipzig 2015 Erik Thelander Nachwuchsforscherpreis des IOM Leipzig (Institutspreis) 2014 Kristina Fischer Nachwuchsforscherpreis des IOM Leipzig 2015 Bernd Abel, Christian Laube, Aleš Charvát Aluminium Innovations Award 2014 (Special Prize) 65

Scientific Events Scientific Meetings Institute Colloquia Lectures Seminars

Scientific Events Prof. Dr. W. Richtering (30.01.2014) Universität Aachen, Germany Responsive microgels with complex structure Prof. Dr. Saskia F. Fischer (06.02.2014) Humboldt-Universität zu Berlin, Germany Quantum, spin and thermal effects in electronic nanostructures C. Stuhldreher (10.04.2014) Sächsisches Staasministerium für Wissenschaft u. Kunst Dresden, Referat Technologiepolitik, Germany Wissenschaft und Wirtschaft – Technologietransfer im Freistaat Sachsen Prof. Dr. Emad Aziz (24.04.2014) Helmholtz-Zentrum Berlin, Germany Material and energy research using soft X-rays to far IR spectroscopies Prof. Dr. B. Röder (15.05.2014) Humboldt-Universität zu Berlin, Germany Singulettsauerstoff: Generierung, direkter Nachweis und Nutzung zur Inaktivierung von Mikroorganismen auf Oberflächen Prof. Dr. J. Meijer (22.05.2014) Universität Leipzig, Germany Functionalized single atoms addressed by ion beam implantation Prof. Dr. H. Bosse (12.06.2014) Physikalisch-Technische Bundesanstalt, Braunschweig, Germany Beiträge der PTB zur Interferometrie für die Weiterentwicklung des SI-Einheitensystems und die Ferti- gungstechnik Dr. J. Clement (19.06.2014) Universitätsklinikum Jena, Germany Interaction of magnetic nanoparticles with human cells Prof. Dr. T. Pompe (26.06.2014) Universität Leipzig, Germany Cell adhesion on polymer substrates of graded elasticity and ligand affinity Dr. S. Koehler (10.07.2014) The University of Manchester, United Kingdom Velocity-map imaging: From gas-phase dynamics to surface reactions Dr. Timothy Davenport (12.09.2014) California Institute of Technology, USA Synthesizing chemical fuels from sunlight, water and carbon dioxide by thermochemical cycles Prof. Dr. P. Sigmund (08.10.2014) University of Southern Denmark, Denmark Landmarks and controversies in ion beam physics Prof. Dr. Liu Chang (09.10.2014) Wuhan University, Center for NanoScience, China Heterostructures based on m-plane ZnO: Structural, electrical and optical properties Prof. Dr. H. Fouckhardt (23.10.2014) Universität Kaiserlautern, Germany Reflektivitätsanisotropie-Spektroskopie zur (Reaktiv-)Ionenätzkontrolle (RIE-RAS) Dr. Veronica Chappa (30.10.2014) Universität Göttingen, Germany Dynamical simulations of coarse grain polymeric systems: Rouse and entangled dynamics 69

Scientific Events Prof. Dr. D. Belder (11.06.2015) Universität Leipzig, Germany Integrierte chemische Mikrolaboratorien Festvortrag - Prof. Dr. D. Guldi (17.06.2015) Universität Erlangen, Germany Current status and perspective of electron transfer chemistry Prof. Dr. J. Weissmüller (25.06.2015) TU Hamburg-Harburg, Germany Mechanics and mechanical behavior of solids: Role of capillarity Prof. Dr. W. Bolse (02.07.2015) Universität Stuttgart, Germany In-Situ SEM Untersuchungen der Modifikation von Oberflächen und dünnen Schichten durch hochener- getische Ionen Prof. Dr. N. Moncoffre (09.07.2015) CNRS Villeurbanne, Lyon, France Radiation induced modifications in nuclear materials Prof. R. C. Flagan (28.10.2015) California Institute of Technology, Pasadena, USA Airborne nanoparticle measurements for health and new particle formation studies Prof. Dr. R. Smith (29.10.2015) Loughborough University, UK Atomistic modelling of sputtering and thin film growth Prof. Dr. R. Seidel (05.11.2015) Universität Leipzig, Germany Single-molecule nanomechanics Dr. S. Facsko (12.11.2015) Helmholtz-Zentrum Dresden-Rossendorf, Germany Pre-equilibrium dynamics of highly charged ions at surfaces and carbon nanomembranes Prof. Dr. R. Brunner (26.11.2015) Ernst-Abbe-Hochschule Jena, Fachbereich SciTec, Germany Micro- and nanostructures for applications in optical instruments Prof. Dr. C. Deibel (03.12.2015) TU Chemnitz, Germany Fundamental processes in organic and hybrid solar cells Prof. Dr. E. Wendler (10.12.2015) Friedrich-Schiller-Universität Jena, Germany Primary processes of damage formation in semiconductors Lectures B. Abel Physikalische Chemie für Fortgeschrittene Universität Leipzig, Fakultät für Chemie und Mineralogie Summer 2014, Summer 2015 71

A. Schulze Funktionskontrolle an komplexen Oberflächen Universität Leipzig, Fakultät für Chemie und Mineralogie Winter 2015/16 A. Schulze, K. Siefermann and A. Varga Recent Trends in Chemistry Universität Leipzig, Fakultät für Chemie und Mineralogie Summer 2014 K. Siefermann, H. Risselada and A. Varga Aktuelle Entwicklungen in der Chemie Universität Leipzig, Fakultät für Chemie und Mineralogie Summer 2015 Seminars B. Abel Soft Matter Seminar Universität Leipzig, Fakultät für Chemie und Mineralogie Winter 2015/16, Summer 2015, Winter 2014/15, Summer 2014 S.G. Mayr Materialwissenschaftliches Seminar Universität Leipzig, Fakultät für Physik und Geowissenschaften Winter 2015/16, Summer 2015, Winter 2014/15, Summer 2014 B. Rauschenbach Materialwissenschaftliches Seminar Universität Leipzig, Fakultät für Physik und Geowissenschaften Winter 2015/16, Summer 2015, Winter 2014/15, Summer 2014 A. Schulze Funktionskontrolle an komplexen Oberflächen Universität Leipzig, Fakultät für Chemie und Mineralogie Winter 2015/16 D. Spemann Kernphysik Universität Leipzig, Fakultät für Physik und Geowissenschaften Winter 2015/16 Teilchenphysik Universität Leipzig, Fakultät für Physik und Geowissenschaften Winter 2015/16 Scientific Events 73

Publications and Presentations Publications in Journals and Books Conference Proceedings Talks Posters Patents

Publications in Journals and Books C. Elsner, D. Heinz, A. Prager, W. Knolle, K. Zimmer Phase separation micromoulding and photopatterning based on radiation induced free radical polymerisation of acrylates for the microfabrication of porous monolithic structures J. Micromech. Microeng. 24 (2014) 095002. C. Elsner, B. Abel Ultrafast high-resolution mass spectrometric finger pore imaging in latent finger prints Sci. Rep. 4 (2014) 6905. C. Elsner, A. Prager, U. Decker, S. Naumov, B. Abel Tailored nano- and micrometer sized structures of gold-nanoparticles at polymeric surfaces via photochemical and kinetic control of the synthesis and deposition process Am. J. Nano Res. Appl., Special Issue: Advanced Functional Materials 2(6-1) (2014) 1-8. M. Engler, S. Macko, F. Frost, T. Michely Evolution of ion beam induced patterns on Si(001) Phys. Rev. B 89 (2014) 245412, 1-14. M. Engler, F. Frost, S. Müller, S. Macko, M. Will, R. Feder, D. Spemann, R. Hübner, S.Facsko, T. Michely Silicide induced ion beam patterning of Si(001) Nanotechnology 25 (2014) 115303. R. Feder, C. Bundesmann, H. Neumann, B. Rauschenbach Ion beam sputtering of germanium - Energy and angular distribution of sputtered and scattered particles Nucl. Instrum. Meth. B 334 (2014) 88-95. B.B. Fernandes, S. Mändl, R.M. Oliveira, M. Ueda Mechanical properties of nitrogen-rich surface layers on SS304 treated by plasma immersion ion implantation Appl. Surf. Sci. 310 (2014) 278-283. A. Finzel, J.W. Gerlach, J. Lorbeer, F. Frost, B. Rauschenbach High-fluence hyperthermal ion irradiation of gallium nitride surfaces at elevated temperatures Appl. Surf. Sci. 317 (2014) 811-817. K. Fischer, R. Gläser, A. Schulze Nanoneedle and nanotubular titanium dioxide PES mixed matrix membrane for photocatalysis Applied Catalysis B 160-161 (2014) 456-464. R. Flyunt, W. Knolle, A. Kahnt, S. Eigler, A. Lotnyk, T. Häupl, A. Prager, D. Guldi, B. Abel Efficient route to high-quality graphene materials: Kinetically controlled electron beam induced reduction of graphene oxide in aqueous dispersion Am. J. Nano Res. Appl., Special Issue: Advanced Functional Materials Vol. 2, No. 6-1 (2014) 9-18. R. Flyunt, W. Knolle, A. Kahnt, A. Prager, A. Lotnyk, J. Malig, D. Guldi, B. Abel Mechanistic aspects of the radiation-chemical reduction of graphene oxide to graphene-like ma- terials Int. J. Radiat. Biol. 90 (2014) 486-494. L. Fricke, T. Böntgen, J. Lorbeer, C. Bundesmann, R. Schmidt-Grund, M. Grundmann An extended drude model for the in-situ spectroscopic ellipsometry analysis of ZnO thin layers and surface modifications Thin Solid Films 571 (2014) 437441. D. Friedrich, C. Wöckel, S. Küsel, R. Konrath, H. Krautscheid, R. Denecke, B. Abel Investigations on the hydrothermal synthesis of pure and Mg-doped nano-CuCrO2 Am. J. Nano Res. Appl. 2 (2014) 53-60. 77

Publications in Journals and Books S. Mändl, J. Lutz, C. Díaz, J.W. Gerlach, J.A. García Influence of reduced current density on diffusion and phase formation during PIII nitriding of aus- tenitic stainless steel and CoCr alloys Surf. Coat. Tech. 239 (2014) 116-122. S. Mändl, R. Dunkel, D, Hirsch, D. Manova Intermediate stages of CrN precipitation during PIII nitriding of stainless steel Surf. Coat. Tech. 258 (2014) 722-726. S. Mändl, J. Lutz, C. Díaz, J.W. Gerlach, J.A. García Influence of reduced current density on diffusion and phase formation during PIII nitriding of aus- tenitic stainless steel and CoCr alloys Surf. Coat. Tech. 256 (2014) 78-84. D. Manova, D. Hirsch, J.W. Gerlach, S. Mändl, H. Neumann, B. Rauschenbach In-situ investigation of phase formation during low energy ion nitriding of Ni80Cr20 alloy Surf. Coat. Tech. 259 (2014) 434-441. D. Manova, S. Mändl, J.W. Gerlach, D. Hirsch, H. Neumann, B. Rauschenbach In-situ x-ray diffraction investigations during low energy ion nitriding of austenitic stainless steel grade 1.4571 J. Phys. D Appl. Phys. 47 (2014) 365301. D. Manova, S. Mändl, H. Neumann, B. Rauschenbach Analysis of in-situ XRD measurements for low energy ion beam nitriding of austenitic stainless steels Surf. Coat. Tech. 256 (2014) 64-72. G. Mirschel, U. Helmstedt, T. Scherzer, U. Decker, L. Prager Monitoring of the degree of condensation in alkoxysiloxane layers by NIR reflection spectroscopy Ind. Eng. Chem. Res. 53 (2014) 16813-16819. G. Mirschel, O. Daikos, K. Heymann, T. Scherzer, B. Genest, C. Sommerer, C. Steckert In-line monitoring of the conversion in UV-cured printed layers by NIR spectroscopy in an offset printing press Progr. Org. Coat. 77 (2014) 719-724. G. Mirschel, O. Daikos, K. Heymann, U. Decker, T. Scherzer, C. Sommerer, B. Genest, C. Steckert In-line monitoring of printing processes in an offset printing press by NIR spectroscopy: Correla- tion between the conversion and the content of extractable acrylate in UV-cured printing inks Progr. Org. Coat. 77 (2014) 1682-1687. S. Naumov, W. Knolle, J. Becher, M. Schnabelrauch, S. Reichelt Electron-beam generated porous dextran gels: Experimental and quantum chemical studies Int. J. Rad. Biol. 90 (2014) 503-511. S. Naumov, W. Knolle, S. P. Naumov, A. Pöppl, I. Janovský The dynamical behavior of the s-trioxane radical cation: A low-temperature EPR and theoretical study Molecules 19 (2014) 17305-17313. A. Neff, O. Naumov, T.-J. Kühn, N. Weber, M. Merkel, B. Abel, A. Varga, K. Siefermann High resolution imaging of a multi-walled carbon nanotube with energyfiltered photoemission electron microscopy Am. J. Nano Res. Appl. 2 (2014) 27-33. O. Öztürk, M. Fidan, S. Mändl MFM imaging of expanded austenite formed in stainless steel and CoCr alloys Surf. Coat. Tech. 256 (2014) 15-22. D. Poppitz, A. Lotnyk, J.W. Gerlach, B. Rauschenbach Microstructure of porous gallium nitride nanowall networks Acta Mater 65 (2014) 98-105. 79

Publications in Journals and Books K. Schröck, H. Schneider, J. Lutz, M. Hacker, S. Mändl, M. Kamprad, M. Schulz-Siegmund Cytocompatibility of nitrogen plasma ion immersed medical cobalt-chromium alloys J. Biomed. Mater. Res. A102 (2014) 1744-1754. C. Schurig, C.W. Müller, C. Höschen, A. Prager, E. Kothe, H. Beck, A. Miltner, M. Kästner Methods for visualising active microbial benzene degraders in situ microcosms Appl. Microbiol. Biotechnol 2 (2014) 957-968. A. Shalabney, I. Khalaila, Ch. Grüner, B. Rauschenbach, I. Abdulhalim SERS biosensor using metallic nano-sculptured thin films for the detection of endocrine disrupt- ing compound biomarker vitellogenin Small 10 (2014) 3579-3514. A. Shavorskiy, S. Neppl, D. Slaughter, J. Cryan, K. Siefermann Sub-nanosecond time-resolved high-pressure x-ray photoelectron spectroscopy setup for pulsed and constant wave x-ray light sources Rev. Sci. Instrum. 85 (2014) 093102. K. Siefermann, C. Pemmaraju, S. Neppl, A. Shavorskiy, A. Cordones Atomic scale perspective of ultrafast charge transfer at a dye-semiconductor interface J. Phys. Chem. Lett. 5 (2014) 2753-2759. A. Sobottka, L. Drößler, C. Hossbach, B. Abel, U. Helmstedt A flexible research reactor for atomic layer deposition with a sample-transport chamber for in Vacuo analytics Am. J. Nano Res. Appl. 2 (2014) 34-38. C. Steinberg, K. Dhima, D. Blenskens, A. Mayer, S. Wang, M. Papenheim, H.-C. Scheer, J. Zajadacz, K. Zimmer A scalable anti-sticking layer process via controlled evaporation Microelectron. Eng. 123 (2014) 4-8. C. Steinberg, D. Blenskens, K. Dhima, S. Wang, M. Papenheim, H.-C. Scheer, J. Zajadacz, K. Zimmer Guided wrinkling with nanoimprinted SU-8 surfaces J. Vac. Sci. Techn. B32 (2014) 06FG05. X. Sun, E. Thelander, P. Lorenz, J.W. Gerlach, U. Decker, B. Rauschenbach Nanosecond laser-induced phase transitions in pulsed laser deposition-deposited GeTe films J. Appl. Phys. 116 (2014) 133501. R.C. Suryaprakash, F. Lohmann, M. Wagner, B. Abel, A. Varga Spray drying as a novel and scalable fabrication method for nanostructured CsH2PO4, Pt-thin-film composite electrodes for solid acid fuel cells RSC Adv. 4 (2014) 60429. M. Teichmann, J. Lorbeer, F. Frost, B. Rauschenbach Ripple coarsening on ion beam-eroded surfaces Nanoscale Res. Lett. 9 (2014) 439. E. Thelander, J. W. Gerlach, U. Ross, A. Lotnyk, B. Rauschenbach Low temperature epitaxy of Ge-Sb-Te films on BaF2(111) by pulsed laser deposition Appl. Phys. Lett. 105 (2014) 221908. E. Thelander, J.W. Gerlach, U. Roß. F. Frost, B. Rauschenbach Epitaxial growth of Ge-Sb-Te films on KCl by high deposition rate pulsed laser deposition J. Appl. Phys. 115 (2014) 213504. A. Varga Progress in solid acid fuel cell electrodes Am. J. Nano Res. Appl. 2 (2014) 1-5. 81

Publications in Journals and Books A. Arabi-Hashemi, R. Witte, A. Lotnyk, R. A. Brand, A. Setzer, P. Esquinazi, H. Hahn, R. S. Averback, S.G. Mayr Ion-irradiation-assisted tuning of phase transformations and physical properties in single crystal- line Fe7Pd3 ferromagnetic shape memory alloy thin films New J. Phys 17 (2015) 053029. Th. Arnold, F. Pietag Ion beam figuring machine for ultra-precision silicon spheres correction Precision Engineering 41 (2015) 119-125. M. Baklanov, L. Zhang, J.-F. de Marneffe, M. Heyne, S. Naumov, Y. Sun, A. Zotovich, Z. El Otell, S. De Gendt, F. Vajda Improved plasma resistance for porous low-k dielectrics by pore stuffing approach ECS Journal of Solid State and Technology 4(1) (2015) 3098-3107. V. Baranwal, J.W. Gerlach, A. Lotnyk, B. Rauschenbach, H. Karl, S. Ojha, D.K.Avasthi, D. Kanjilal, A.C. Pandey Embedded Ge nanocrystals in SiO2 synthesized by ion implantation J. Appl. Phys. 118 (2015) 134303. F. Bauer, U. Decker, S. Naumov, C. Riedel Photoinitiator-free curing of acrylate-based nanocomposites by monochromatic ultra violet irra- diation, in radiation curing of composites for enhancing their features and utility in health care and industry International Atomic Energy Agency, Vienna, ISBN 978 92 0 103815 9 (2015) 82-96. K. Bente, A. König, F. Dehn, P. Krüger, R. Wirth, D. Hirsch, T. Münster, C. Berthold Vergleichende computertomographische und elektronenmikroskopische Studien zu eisenzeitli- cher Korallenzier Metalla (Deutsches Bergbau Museum Bochum) Sonderheft 7 (2015) 59-61. D. Breite, M. Went, A. Prager, A. Schulze Tailoring membrane surface charges: A novel study on electrostatic interactions during mem- brane fouling Polymers 7 (2015) 2017-2030. S. N. Britvin, A. Lotnyk Water-soluble phosphine capable of dissolving elemental gold: The missing link between 1,3,5- triaza-7-phosphaadamantane (PTA) and verkades ephemeral ligand J. Am. Chem. Soc. 137 (2015) 5526-5535. J. Buchwald and S.G. Mayr Influence of surface stresses on indentation response Nanotechnology 26 (2015) 125704. C. Bundesmann, R. Feder, T. Lautenschläger, H. Neumann Energy distribution of secondary particles in ion beam deposition process of Ag: Experiment, calculation and simulation Contrib. Plasma Phys. 55 (2015) 737-746. C. Bundesmann, R. Feder, R. Wunderlich, U. Teschner, M. Grundmann, H. Neumann Ion beam sputter deposition of Ge films: Influence of process parameters on film properties Thin Solid Films 589 (2015) 487-492. T. Csizmadia, T. Smausz, C. Tapai, J. Kopniczky, X. Wang, M. Ehrhardt, P. Lorenz, K. Zimmer, L. Orosz, E. Varga, A. Oszko, B. Hopp Comparison of the production of nanostructures on bulk metal samples by picosecond laser ab- lation at two wavelengths for the fabrication of low-reflective surfaces J. Laser Micro and Nanoeng. 10 (2015) 110-118. A. de Luca, A. Weidt, M. Zink, S.G. Mayr, A. E. Markaki Effect of microgrooved surface topography on osteoblast maturation and protein adsorption J. Biomed. Mater. Res.: Part A. 103 (8) (2015) 2689 2700. 83

Publications in Journals and Books P. Lorenz, T. Smausz, T. Csizmadia, M. Ehrhardt, K. Zimmer, B. Hopp Shadowgraph studies of laser-assisted non-thermal structuring of thin layers on flexible sub- strates by shock-wave-induced delamination processes Appl. Surf. Sci. 336 (2015) 43-47. P. Lorenz, M. Klöppel, T. Smausz, T. Csizmadia, M. Ehrhardt, K. Zimmer, B. Hopp Dynamics of the laser-induced nanostructuring of thin metal layers: Experiment and theory Mater. Res. Express 2 (2015) 026501. P. Lorenz, M. Klöppel, T. Smausz, T. Csizmadia, M. Ehrhardt, K. Zimmer, B. Hopp Time dependency of the laser-induced nanostructuring process of chromium layers with different thicknesses on fused silica Appl. Surf. Sci. 336 (2015) 176-181. A. Lotnyk, D. Poppitz, U. Ross, J.W. Gerlach, F. Frost, S. Bernütz, E. Thelander, B. Rauschenbach Focused high- and low-energy ion milling for TEM specimen preparation Microelectron. Reliab. 55 (2015) 2119-2125. D. Manova, C. Díaz, L. Pichon, G. Abrasonis, S. Mändl Comparability and accuracy of nitrogen depth profiling in nitrided austenitic stainless steel Nucl. Instrum. Meth. B 349 (2015) 106-113. A. Meiners, M. Leck, B. Abel Compact high-velocity atmospheric pressure dielectric barrier plasma jet in ambient air Plasma Sci. Tech. 17 (2015) 14-19. D. Milovanovic, A. Honigmann, S. Koike, F. Gottfert, G. Pahler, M. Junius, S. Mullar, U. Diederichsen, A. Janshoff, H. Grubenmuller, H. J. Risselada, C. Eggeling, S. W. Hell Hydrophobic mismatch sorts SNARE proteins into distinct membrane domains Nat. Commun. 6 (2015) 5984. P. Nalawade, S. Naumov, S. Kapoor Hidden chemistry of substituted aniline radical cations in water: A mechanistic study J. Phys. Org. Chem. 28 (2015) 2-9. F. Niefind, J. Djamil, W. Bensch, B.R. Srinivasan, I. Sinev, W. Grunert, M. Deng, L. Kienle, A. Lotnyk, M.B. Mesch, J. Senker, L. Durag, T. Beweries Room temperature synthesis of an amorphous MoS2 based composite stabilized by N-donor lig- ands and its light-driven photocatalytic hydrogen production RSC Adv. 5 (2015) 67742-67751. H. Osadnik, M. Schopfel, E. Heidrich, D. Mehner, H. Lolie, C. Parthier, H. J. Risselada, H. Grubmuller, M. T. Stubbs, T. Bruser PspF-binding domain PspA(1-144) and the PspA center dot F complex: New insights into the coiled-coil-dependent regulation of AAA plus proteins Mol. Microbiol. 98 (2015) 743-759. H. Paetzelt, G. Böhm, Th. Arnold Etching of silicon surfaces using atmospheric plasma jets Plasma Sources Sci. Technol. 24 (2015) 025002. K. Pardun, L. Treccani, E. Volkmann, P. Streckbein, C. Heiss, J.W. Gerlach, S. Mändl, K. Rezwan Magnesium containing mixed coatings on zirconia for dental implants: Mechanical characteriza- tion and in vitro behavior J. Biomater. Appl. 30 (2015) 104-118. D. Poppitz, A. Lotnyk, J.W. Gerlach, J. Lenzner, M. Grundmann, B. Rauschenbach An aberration-corrected STEM study of structural defects in epitaxial GaN thin films grown by ion beam assisted MBE Micron 73 (2015) 1-8. 85

Publications in Journals and Books R. M. P. Tanyag, C. Bernando, C. F. Jones, C. Bacellar, K. R. Ferguson, D. Anielski, R. Boll, S. Carron, J. P. Cryan, L. Englert, S. W. Epp, B. Erk, L. Foucar, L. F. Gomez, R. Hartmann, D. M. Neumark, D. Rolles, B. Rudek, A. Rudenko, K. Siefermann Communication: X-ray coherent diffractive imaging by immersion in nanodroplets Struct. Dynam. 2 (2015) 051102. J. Taubert, B. Hou, H. J. Risselada, D. Mehner, H. Lunsdorf, H. Grubmuller, T. Bruser TatBC-independent TatA/Tat substrate interactions contribute to transport efficiency Plos One 10 (2015) 0119761. T. Titze, C. Chmelik, J. Kullmann, L. Prager, E. Miersemann, R. Gläser, D. Enke, J. Weitkamp, J. Kärger Microimaging of transient concentration profiles of reactant and product molecules during cata- lytic conversion in nanoporous materials Angew. Chem.-Int. Edit. 54 (2015) 5060-5064. C. Vass, B. Kiss, R. Flender, Z. Felház, P. Lorenz, M. Ehrhardt, K. Zimmer Comparative study on grating fabrication in transparent materials by TWIN-LIBWE and ultrashort pulsed ablation techniques J. Laser Micro/Nanoeng. 10 (2015) 38-42. F. Wiederschein, E. Vohringer-Martinez, A. Beinsen, F. Postberg, J. Schmidt, R. Srama, F. Stolz, H. Grubmuller, B. Abel Charge separation and isolation in strong water droplet impacts Phys. Chem. Chem. Phys. 17 (2015) 6858-6864. P. C. With, N. Wilde, A. Modrow, S. Fichtner, B. Bohringer R. Glaser Polymer-based spherical activated carbons in combination with TS-1 as efficient epoxidation catalysts Chem. Eng. Technol. 38 (2015) 1671-1676. P. C. With, N. Wilde, A. Modrow, S. Fichtner, B. Bohringer, R. Glaser Polymer-based spherical activated carbons in combination with TS-1 as efficient catalyst for epoxidation Chem. Ing. Tech. 87 (2015) 1424-1430. J. Zajadacz, P. Lorenz, F. Frost, R. Fechner, C. Steinberg, H.-C. Scheer, K. Zimmer Reactive ion beam etching of fused silica using vertical lamellar patterns of PS-b-PMMA diblock copolymer masks Microelectron. Eng. 141 (2015) 289-293. 87

Conference Proceedings P. Lorenz, S. Zehnder, M. Ehrhardt, F. Frost, K. Zimmer, P. Schwaller Nanosecond laser-induced back side wet etching of fused silica with a copper-based absorber liquid Proc. SPIE 8967 (2014) 89670A A. Lotnyk Focused low energy-argon ion milling: A must-have tool for Cs-corrected TEM Imaging & Microscopy 2 (2014) 32-33 A. Lotnyk, D. Poppitz, J.W. Gerlach, B. Rauschenbach Imaging of light elements by annular dark-field Cs-corrected STEM Paper Nr. ISBN 978-80-260-6721-4, IMC 18 Proceedings edited by Pavel Hozak, Prag, Czech Republic (2014) IT-2-O-1555 H. Paetzelt, G. Böhm, Th. Arnold Ultra precision waviness and figure error correction of silicon crystals by local plasma jet ma- chining Paper Nr. P6.25, EUSPEN 14th International Conference, Dubrovnik, Croatia, 02.-06.06. (2014) 140V2 S. Reichelt, S. Richter, A. Prager, W. Knolle, J. Becher, J. Weisser, M. Schnabelrauch Makroporöse Elektronenstrahl-generierte 3D Gerüststrukturen Jahrestagung der Deutschen Gesellschaft für Biomaterialien, Dresden, Germany, 06.-08.11. (2014) S11 S. Reichelt, S. Richter, W. Knolle, J. Becher, J. Weisser, M. Schnabelrauch Novel electron-beam derived macroporous 3D cell culture scaffolds CellMat 2014, Dresden, Germany, 22.-24.10. (2014) U. Ross, A. Lotnyk, E. Thelander, B. Rauschenbach Quantitative structural and chemical investigation of amorphous and metastable crystalline phase-change alloy thin films by Cs-corrected STEM Paper Nr. ISBN 978-80-260-6721-4, IMC 18 Proceedings edited by Pavel Hozak, Prag, Czech Republic (2014) MS-3-O-1956 A. Schulze, B. Marquardt, M. Went, I. Thomas Electron-beam-induced grafting of hydrophilic polymers to hydrophobic membrane surfaces Paper Nr. PO-1-00603, ICOM 2014 - 10th International Congress on Membranes and Membrane Pro- cesses, Suzhou, China, 20.-25.07. (2014) A. Schulze, A. Stoelzer, K. Striegler, S. Starke Bio-inspired self-cleaning polymer membranes Paper Nr. OR-1-00602, ICOM 2014 - the 10th International Congress on Membranes and Membrane Processes, Suzhou, China, 20.-25.07. (2014) A. Schulze, B. Marquardt, M. Went, I. Thomas Grafting of hydrophilic polymers to hydrophobic membrane surfaces via electron beam irradia- tion Paper Nr. P3.21, 15th Aachener Membrankolloquium, Aachen, Germany, 12.-13.11. (2014) 431-432 S. Srivastava, A. Shalabney, I. Khalaila, C. Grüner, B. Rauschenbach, I. Abdulhalim Highly sensitive SERS based nano-sculptured thin film biosensor for the detection of vitellogen- in: an endocrine disruption biomarker Paper Nr. SeM3C.3, Optical Sensors 2014, Barcelona, Spain, 27.-31.07. (2014) S. Zehnder, P. Lorenz, M. Ehrhardt, K. Zimmer, P. Schwaller Laser-induced processes on the back side of dielectric surfaces using a CuSO4-based absorber liquid Proc. SPIE 8968 (2014) 896812 89

Conference Proceedings A. Lotnyk, S. Bernütz, U. Ross, X. Sun, E. Thelander, M. Ehrhardt, B. Rauschenbach Atomic structure of Ge-Sb-Te thin films studied by high-resolution Cs-corrected STEM International Workshop on Advanced and In-situ Microscopies of Functional Nanomaterials and Devices, Hamburg, Germany, 08.-10.07. (2015) 44-45 H. Paetzelt, G. Böhm, Th. Arnold Surface error correction with fine focused plasma jets Paper Nr. EOSMTOC Poster 16, EOSMTOC 2015, München, Germany, 22.-25.06. (2015) D. Pagano, F. Scortecci, C. Bundesmann, C. Eichhorn, F. Scholze, H. Neumann, H. Leiter, H. Kersten, S. Gauter, R. Wiese, R. Blott, P.J. Klar, K. Holste, B. Meyer, S. Mazouffre, A. Bulit, J. Gonzales del Amo Qualification of the AEPD system as a standard on-ground tool for electric propulsion thruster Paper Nr. IEPC-2015-363, 34th International Electric Propulsion Conference, Hyogo-Kobe, Japan, 04.-10.7. (2015) F. Pietag, Th. Arnold Ultra-precision surface finishing using pulsed ion beams Proceedings of EUSPEN International Conference 2015, Leuven, Belguim, 01.-05.06. (2015) 361 D. Poppitz, A. Lotnyk, J. Gerlach, B. Rauschenbach Aberration-corrected STEM study of polar and non-polar epitaxial GaN thin films produced by ion-beam nitridation of Ga droplets on different substrate materials Paper Nr. MS2.P040, Microscopy Conference 2015, Göttingen, Germany, 06.-11.09. (2015) 83-84 S. Reichelt Introduction to macroporous cryogels Springer Sci+Business Media, Affinity Chromatography 1286 (2015) 173-181 U. Roß, A. Lotnyk, E. Thelander, B. Rauschenbach Cs-corrected STEM characterisation of textured and epitaxial Ge-Sb-Te thin films Paper Nr. MS3.P066, Microscopy Conference 2015, Göttingen, Germany, 06.-11.09. (2015) 127-128 U. Roß, A. Lotnyk, E. Thelander, B. Rauschenbach High-resolution STEM investigation of textured and epitaxial Ge-Sb-Te thin films E\PCOS 2015, Amsterdam, Netherlands, 06.-08.09. (2015) 161-162 A. Schulze, M. Went, A. Prager Membrane functionalization with hyperbranched polymers Paper Nr. G-082, Euromembrane 2015, Aachen, Germany, 06.-10.09. (2015) 91

Presentations C. Bundesmann, R. Feder, H. Neumann Tailoring of thin film properties by (dual) ion beam sputter deposition 4. Optik-Kolloquium Dünne Schichten in der Optik (ThGOT), Leipzig, Germany, 04.09.2014 C. Bundesmann, H. Neumann, M. Schubert In-situ thin film characterization by spectroscopic ellipsometry Kolloquium, Institut Solare Brennstoffe, Helmholtz-Zentrum Berlin, Berlin, Germany, 21.05.2014 C. Bundesmann, C. Eichhorn, F. Scholze, H. Neumann Advanced in-situ electric propulsion diagnostics Horizon 2020, Electric Propulsion Innovation and Competitiveness (EPIC), Project Workshop, Brüssel, Belgien, 25.-28.11.2014 M. Ehrhardt, P. Lorenz, F. Frost, J. Zajadacz, K. Zimmer Processes at multi-pulse laser embossing of submicron surface structures 15th International Symposium on Laser Precision Microfabrication (LPM 2014), Vilnius, Lithuania, 17.-20.06.2014 M. Ehrhardt, P. Lorenz, A. Lotnyk, H. Romanus, E. Thelander, K. Zimmer Pattern transfer of sub-micrometre-scaled structures into solid copper by laser embossing LANE 2014, 8th International Conference on Photonic Technologies, Fürth, Germany, 08.-11.09.2014 C. Eichhorn, F. Scholze, C. Bundesmann, H. Neumann Non-intrusive plasmadiagnostics in ion thrusters: Current and planned activities at IOM 5th Russian-German Conference on Electric Propulsion and Their Applications, Dresden, Germany, 07.-12.09.2014 C. Eichhorn, F. Scholze, C. Bundesmann, H. Neumann Erweiterung der plasmadiagnostischen Instrumente des AEPD Systems mit optischen Methoden: Status XXI. Erfahrungsaustausch Oberflächentechnologie mit Plasma- und Ionenstrahlprozessen, Mühlleithen, Germany, 12.-14.03.2014 C. Eichhorn, M. Tartz, F. Scholze, C. Bundesmann, H. Neumann Validated dynamic life time modelling and related material investigations Horizon 2020, Electric Propulsion Innovation & Competitiveness (EPIC), Project Workshop, Brüssel, Belgien, 25.-28.11.2014 C. Elsner, Th. Arnold VUV-Photonen und kalte atmosphärische Mikrowellenplasmajets für die Behandlung empfindli- cher Oberflächen Workshop Innovative Oberflächentechnik und deren Analyseverfahren, Jena, Germany, 11.06.2014 C. Elsner, B. Abel Aus der Hand lesen - ein zweiter Blick auf Fingerabdruckspuren Lange Nacht der Wissenschaften, Leipzig, Germany, 27.06.2014 O. Faehnle, E. Langenbach, F. Frost, R. Fechner, A. Schindler, M. Cumme, H. Biskup, C. Wünsche, R. Rascher Generation and field testing of roughness reference samples for industrial testing of surface roughness levels below 0.5 nm Sq EOSAM 2014, Berlin, Germany, 15.-19.09.2014 R. Feder, H. Neumann, C. Bundesmann, B. Rauschenbach Systematic investigations of low energy ion beam sputtering of Germanium DPG Frühjahrstagung SKM, Dresden, Germany, 30.03.-04.04.2014 R. Feder, C. Bundesmann, C. Eichhorn, D. Manova, H. Neumann Investigations on ion beam sputtering related to electric propulsion 5th Russian-German Conference on Electric Propulsion and Their Application, Dresden, Germany, 07.-12.09.2014 93

Presentations D. Manova, S. Mändl, H. Neumann, B. Rauschenbach In-situ observation of the decay of an expanded CoCr:N phase into CrN and fcc phase 15th Int. Conf. on Plasma Surface Engineering, Garmisch-Partenkirchen, Germany, 15.-19.09.2014 D. Manova, S. Mändl, H. Neumann, B. Rauschenbach In situ XRD investigations of nitriding of CoCr XXI. Erfahrungsaustausch Oberflächentechnologie mit Plasma- und Ionenstrahlprozessen, Mühlleithen, Germany, 12.-14.03.2014 H. Neumann Ionenquellenentwicklungen am IOM 2. Sächsisches Präparatorentreffen, Leipzig, Germany, 22.05.2014 A. Nickel, F. Pietag, Th. Arnold Mathematische Grundlagen der Verweilzeitmethode mit Pulsweitenmodulation für eine 3-Achsenanlage Workshop: Ionenstrahlformgebung unter Nutzung von Pulsweiten modulierten Quellen, IOM, Leipzig, Germany, 18.09.2014 T. Pelras, K. Heymann, O. Daikos, S. Naumov, W. Knolle, T. Scherzer Efficiency of polyhalogenated acrylic monomers for initiation of UV photopolymerization reac- tions 3th European Symposium of Photopolymer Science (ESPS 2014), Wien, Austria, 09.-12.9.2014 D. Poppitz, J.W. Gerlach, A. Lotnyk, B. Rauschenbach Aberration-corrected STEM investigation of epitaxial GaN thin films deposited by IBA-MBE Workshop Ionenstrahlen & Nanostrukturen, Paderborn, Germany, 21.07.2014 D. Poppitz, A. Lotnyk, J.W. Gerlach, B. Rauschenbach Aberration-corrected STEM investigation of epitaxial GaN thin films DPG Frühjahrstagung SKM, Dresden, Germany, 01.04.2014 D. Poppitz, A. Lotnyk, J.W. Gerlach, B. Rauschenbach Präparation von TEM-Lamellen mittels fokussiertem hoch- und niederenergetischen Ionenstrahl- ätzen 2. Sächsisches Präparatorentreffen, Leipzig, Germany, 22.05.2014 D. Poppitz, A. Lotnyk, J. W. Gerlach, B. Rauschenbach Characterization of epitaxial GaN thin films by aberration-corrected scanning transmission elec- tron microscopy XV International Conference on Electron Microscopy, Cracow, Poland, 15.-18.09.2014 L. Prager, U. Helmstedt, H. Herrnberger, O. Kahle, F. Kita, W. Knolle, S. Naumov Conversion of polysilazanes into Si-O-Si networks triggered by vacuum ultraviolet irradiation: Design and production of barrier and high barrier films 2014 MRS Spring Meeting and Exhibition, San Francisco, USA, 21.-25.04.2014 B. Rauschenbach, F. Frost, Th. Arnold Ion beam ultra-precision smoothing of surfaces 19th International Conference on Ion Beam Modification of Materials (IBMM), Leuven, Belgium, 14.-19.09.2014 B. Rauschenbach Ultra-low energy ion-solid interaction Kolloquium, Research Center of Material Science, University Nagoya, Japan, 22.08.2014 B. Rauschenbach Nano-sculptured thin films 2th Intern. Conference on Bioinspired and Biobased Chemistry and Materials, Nizza, France 15.-17.10.2014 95

Presentations F. Scholze, H. Neumann Performance modelling of a radio frequency plasma bridge neutralizer 5th Russian-German Conference on Electric Propulsion and Their Applications, Dresden, Germany, 7.-12.09.2014 A. Schulze, A. Stoelzer, K. Striegler, S. Starke Bio-inspired self-cleaning polymer membranes ICOM 2014, 10th International Congress on Membranes and Membrane Processes, Suzhou, China, 20.-25.07.2014 K. Siefermann Monitoring charge transfer at N3-ZnO interfaces via femtosecond time-resolved core level photoe- lectron spectroscopy Bunsentagung, Hamburg, Germany, 30.05.2014 K. Siefermann How to measure ultrafast dynamics in complex systems? 6th Conferenz - From the Witches Cauldrons in Materials Science, Goslar, Germany, 30.04.2014 K. Siefermann Understanding dynamics in complex systems: Ultrafast spectroscopy with high-harmonics and x- ray free electron lasers Seminar, Fritz-Haber-Institut, Berlin, Germany, 18.07.2014 K. Siefermann Understanding dynamics in complex systems: Ultrafast spectroscopy with High-Harmonics and x-ray free electron lasers Symposium -BRAGFOST, Alexander-von-Humboldt Foundation, Recife, Brazil, 28.09.2014 K. Siefermann Ultrafast relaxation dynamics in aqueous environment and charge trasfer at a molecule- semiconductor interface 3th Ertl Symposium on Surface Analysis and Dynamics, Berlin, Germany, 11.11.2014 K. Siefermann Understanding dynamics in complex systems: Ultrafast spectroscopy with high-harmonics and x- ray free electron lasers Seminar, Universität Tübingen, Germany, 26.11.2014 S. Simison, D. Manova, S. Mändl, S. Brühl, L. Escalada Corrosion resistance of AISI 316L stainless steel nitrided by three different plasma assisted tech- niques 69th International Annual Congress of Associação Brasileira de Metalurgia, Materiais e Mineração, Sao Paulo, Brazil, 21.-23.06.2014 X. Sun, E. Thelander, H. Lu, J.W. Gerlach, B. Rauschenbach Ultraviolet laser-induced phase transitions of PLD-deposited GeTe films Annual Conference of the Graduate School BuildMoNa, Leipzig, Germany, 03.-04.03.2014 C. Vass, B. Kiss, R. Flender, P. Lorenz, M. Ehrhardt, K. Zimmer Microstructuring of fused silica: Nanosecond UV laser in TWIN-LIBWE arrangement versus ultra- short pulse ablation 15th International Symposium on Laser Precision Microfabrication (LPM 2014), Vilnius, Lithuania, 17.-20.06.2014 K. Zimmer, X. Wang, P. Lorenz, M. Ehrhardt, L. Bayer, C. Scheit, A. Braun In-process measurement at laser scribing of CIGS thin film solar cells for studying the impact on their electrical characteristics 15th International Symposium on Laser Precision Microfabrication (LPM 2014), Vilnius, Lithuania, 17.-20.06.2014 97

Presentations C. Bundesmann, R. Feder, T. Lautenschläger, H. Neumann Energieaufgelöste Massenspektrometrie bei Zerstäubungsprozessen EFDS-Workshop Diagnostik von Prozessplasmen, Dresden, Germany, 09.12.2015 C. Bundesmann, C. Eichhorn, F. Scholze, H. Neumann, H.J. Leiter, D. Pagano, F. Scortecci Electric propulsion thruster diagnostic activities at IOM 34th International Electric Propulsion Conference, Hyogo-Kobe, Japan, 04.-10.07.2015 C. Bundesmann, R. Feder, T. Lautenschläger, H. Neumann Secondary particle properties in the ion beam sputter process of Ag and Ge 21th International Workshop on Inelastic Ion-Surface Collisions, Donostia-San Sebastián, Spain, 18.-23.10.2015 O. Daikos, S. Naumov, T. Pelras, K. Heymann, W. Knolle, T. Scherzer Analytical investigations and quantum chemical modeling of mechanisms of initiation of photo- polymerization reactions by polyhalogenated acrylic monomers Photopolymerization Fundamentals 2015, Boulder/CO, USA, 13.-16.09.2015 C. Eichhorn, D. Manova, R. Feder, R. Wunderlich, C. Nömayr, C. Zimmermann, H. Neumann Neue Messungen von Zerstäubungsausbeuten an Folien aus verschiedenen Materialien: STIM und Weight-Loss Techniken im Vergleich XXII. Erfahrungsaustausch Oberflächentechnologie mit Plasma- und Ionenstrahlprozessen, Mühlleithen, Germany, 10.-12.03.2015 O. Faehnle, F. Zygalsky, E. Langenbach, F. Frost, R. Fechner, A. Schindler, M. Cumme, H. Biskup, C. Wünsche, R. Rascher Fabrication and qualification of roughness reference samples for industrial testing of surface roughness levels below 0.5 nm Sq SPIE Conference on Optical Manufacturing and Testing XI, San Diego, USA, 09.-11.08.2015 R. Feder, C. Bundesmann, H. Neumann Ionenstrahlzerstäubung von Germanium - energetische und angulare Verteilung der zerstäubten und gestreuten Teilchen XXII. Erfahrungsaustausch Oberflächentechnologie mit Plasma- und Ionenstrahlprozessen, Mühlleithen, Germany, 10.-12.03.2015 A. Finzel, J. W. Gerlach, F. Frost, R. Fechner, M. Teichmann, A. Lotnyk, B. Rauschenbach Epitaxial GaN films deposited on ion-beam structured Si(111) with SiNx intermediate layer Annual BuildMoNa Conference, Leipzig, Germany, 23.-24.03.2015 A. Finzel, J. W. Gerlach, F. Frost, R. Fechner, M. Teichmann, A. Lotnyk, B. Rauschenbach Epitaxial GaN films deposited on ion-beam structured Si(111) with SiNx intermediate layer DPG Frühjahrstagung, Berlin, Germany, 18.03.2015 K. Fischer, R. Gläser, A. Schulze Combination of nanoporous photocatalytic TiO2 with a polymer membrane for water purification 5th Dissemination workshop of the Nano4water cluster, Barcelona, Spain, 20.-21.01.2015 K. Fischer, M. Grimm, J. Meyers, C. Dietrich, R. Gläser, A. Schulze Assembly of nanostructured TiO2 on polymer membranes for photocatalytic water purification 20. Seminartag des GRK 1626/ DBU-Fachkolloquium Chemische Photokatalyse, Regensburg, Germany, 29.-30.01.2015 K. Fischer, R. Gläser, A. Schulze Nanoporous photocatalytic TiO2 on polymer membranes for water purification Euromembrane 2015, Aachen, Germany, 06.-10.09.2015 P. Frach, D. Glöß, H. Bartzsch, T. Goschurny, A. Drescher, C. Gottfried, J.-S. Liebig, J. Hartung, A. Heisig, H. Grune, L. Leischnig, S. Leischnig, H. Neumann, C. Bundesmann Großflächige präzisionsoptische Beschichtungen mittels reaktiven Puls-Magnetron-Sputterns V2015 - Vakuumbeschichtung und Plasmaoberflächentechnik, Dresden, Germany, 12.-15.10.2015 99

Presentations D. Manova, S. Mändl, H. Neumann, B. Rauschenbach Influence of surface treatments on corrosion properties of stainless steel and CoCr alloys Nanobiotec Biophysics Workshop, Valparaiso, Chile, 30.09.-02.10.2015 D. Manova, S. Mändl, H. Neumann, B. Rauschenbach Formation of metastable diffusion layers in Cr-containing alloys after nitrogen insertion 13th Int. Conf. on Plasma Based Ion Implantation, Buenos Aires, Argentina, 05.-09.10.2015 R.G. Nikov, N.N. Nedyalkov, P.A. Atanasov, D. Hirsch, B. Rauschenbach Characterization of Ag nanostructures fabricated by laser-induced dewetting of thin films E-MRS Meeting, Symposium CC, Lille, Frankreich, 11.-15.05.2015 D. Pagano, F. Scortecci, C. Bundesmann, C. Eichhorn, F. Scholze, H. Neumann, H. Leiter, H. Kersten, S. Gauter, R. Wiese, R. Blott, P.J. Klar, K. Holste, B. Meyer, S. Mazouffre, A. Bulit, J. Gonzales del Amo Qualification of the AEPD System as a Standard On-Ground Tool for Electric Propulsion Thruster 34th International Electric Propulsion Conference, Hyogo-Kobe, Japan, 04.-10.07.2015 D. Poppitz Hochaufgelöste, aberrationskorrigierte Elektronenmikroskopie an epitaktisch gewachsenen GaN Dünnschichten Seminar, Fraunhofer IWM, Halle, Germany, 05.03.2015 D. Poppitz, A. Lotnyk, J.W. Gerlach, B. Rauschenbach Aberration-corrected-STEM investigation of epitaxial GaN thin films formed by ion-beam based post-nitridation of Ga droplets DPG Frühjahrstagung SKM, Berlin, Germany, 15.-20.03.2015 B. Rauschenbach, D. Poppitz, A. Lotnyk, J.W. Gerlach Epitaxial GaN films prepared by hyperthermal ion beam assisted molecular beam epitaxy Collaborative Conference on Crystal Growth, Hong Kong, China, 14.-17.12.2015 B. Rauschenbach Ion beam sputter induced sculptured thin films 8th Intern. Meeting on Recent Developments in the Study of Radiation Effects in Matter, Kerteminde, Denmark, 20.-23.09.2015 B. Rauschenbach Nano-sculptured thin films Intern. Conference Negev Global Issues 2015, Ilse Katz Institute for Nanoscale Science and Technology, Ben Gurion University, Beer-Sheva, Israel, 27.-31.05.2015 B. Rauschenbach, C. Grüner Nanostructured thin films by glancing angle deposition Kolloquium, Technion Haifa, Physics Department, Israel, 01.06.2015 S. Richter, R. Schmidt-Grund, C. Bundesmann, S. Ebbinghaus, M. Grundmann Temperature dependent dielectric function of hexagonal YMnO3 9th European Workshop Ellipsometry, Twente, Netherlands, 23.-25.02.2015 U. Roß, A. Lotnyk, E. Thelander, B. Rauschenbach Epitaxial and textured Ge-Sb-Te phase-change thin films investigated by Cs-corrected STEM DPG Frühjahrstagung, Berlin, Germany, 15.-20.03.2015 T. Scherzer, C. Schmidt, K. Heymann Monitoring of photopolymerization reactions by hyphenated photorheometry / NIR spectroscopy measurements International Symposium on Photopolymerization, Beijing, China, 28.6.-01.07.2015 101

Presentations X. Sun, E. Thelander, J. W. Gerlach, B. Rauschenbach Nanosecond laser-induced phase transitions in PLD-deposited GeTe films DPG Frühjahrstagung, Berlin, Germany, 15.-20.03.2015 P. C. With, U. Helmstedt, L. Prager Development of high-barrier films for encapsulation of flexible planar electronic devices PV Days 2015, Halle/Saale, Germany, 27.-28.10.2015 103

Posters A. Finzel, J.W. Gerlach, J. Lorbeer, F. Frost, B. Rauschenbach High-fluence hyperthermal ion irradiation of gallium nitride surfaces at elevated temperatures Workshop Ionenstrahlen & Nanostrukturen, Paderborn, Germany, 20.-22.07.2014 K. Fischer, R. Gläser, A. Schulze Formation and growth of TiO2 nanotubes on top of a PES membrane for water purification 2. Workshop of Leibniz-Network Nano and 3. PHD Retreat of Section D, Berlin, Germany, 16.-18.7.2014 K. Fischer, R. Gläser, A. Schulze Formation and growth of TiO2 nanotubes on top of a PES membrane for water purification ICOM 2014 - the 10th International Congress on Membranes and Membrane Processes, Suzhou, China, 20.07.-25.07.2014 K. Fischer, R. Gläser, A. Schulze Combination of TiO2 nanotubes with a PES membrane to remove pharmaceuticals from water 15th Aachener Membran Kolloquium, Aachen, Germany, 12.-13.11.2014 K. Fischer, R. Gläser, A. Schulze Formation and growth of TiO2 nanotubes on top of a PES membrane for water purification ICOM 2014 - the 10th International Congress on Membranes and Membrane Processes, Suzhou, China, 20.-25.07.2014 L. Fricke, C. Grüner, C. Bundesmann, R. Schmidt-Grund, M. Grundmann Rigorous simulations and analysis of the optical response of silica sculptured thin films 8th Workshop Ellipsometry, Dresden, Germany, 10.-12.03.2014 E.L. Fricke, C. Grüner, C. Bundesmann, R. Schmidt-Grund, M. Grundmann Rigorous simulations and analysis of the optical response of silica sculptured thin films DPG-Frühjahrstagung, Dresden, Germany, 30.03.-04.04.2014 U. Helmstedt, G. Mirschel, U. Decker, T. Scherzer, L. Prager NIR reflection spectroscopy for (in-line) monitoring of alkoxysilane condensation processes 10. ThGOT Thementage Grenz- und Oberflächentechnik, Leipzig, Germany, 02.-03.09.2014 K. Heymann, C. Schmidt, S. Naumov, R. Schubert, T. Scherzer Photoinitiator-free photopolymerization of allophanate urethane acrylates by UV-C and VUV radi- ation 3rd European Symposium of Photopolymer Science (ESPS 2014), Wien, Austria, 09.-12.09.2014 E. Jahangiri, S. Reichelt, I. Thomas, K. Hausmann, D. Schlosser, A. Schulze Biocatalysts for waste water treatment- Trametes versicolor Laccase immobilization on porous supports 4. Joint Conference of the Association for General and Applied Microbiology (VAAM) and the Society of Hygiene and Microbiology (DGHM), Dresden, Germany, 05.-08.10.2014 A. Kleiman, D. Manova, S. Mändl, J.M. Meichtry, M.I. Litter, A. Márquez Photoactivity of titanium dioxide films grown by cathodic arc doped with Cu and N 15th Int. Conf. on Plasma Surface Engineering, Garmisch-Partenkirchen, Germany, 15.-19.09.2014 P. Lorenz, F. Frost, M. Ehrhardt, K. Zimmer Laser-induced nanostructuring of dielectric surfaces 15th International Symposium on Laser Precision Microfabrication (LPM 2014), Vilnius, Lithuania, 17.-20.06.2014 P. Lorenz, X. Wang, M. Ehrhardt, L. Bayer, A. Braun, K. Zimmer Ablative and delamination laser-structuring of CIGS solar cell stacks on flexible substrates 15th International Symposium on Laser Precision Microfabrication (LPM 2014), Vilnius, Lithuania, 17.-20.06.2014 G. Mirschel, O. Daikos, K. Heymann, U. Decker, T. Scherzer In-line monitoring of printing processes by NIR spectroscopy 3rd European Symposium of Photopolymer Science (ESPS 2014), Wien, Austria, 09.-12.9.2014 105

Posters 2015 K. Bente, A. König, F. Dehn, P. Krüger, R. Wirth, D. Hirsch, T. Münster, C. Berthold Vergleichende computertomographische und elektronenmikroskopische Studien zu eisenzeit- licher Korallenzier Jahrestagung Archäometrie und Denkmalpflege, Mainz, Germany, 25.-28.03.2015 H. Bhuyan, M. Favre, M. Cisternas, A. Henriquez, E. Wyndham, S. Mändl, D. Manova Nitriding of super-ferritic stainless steel by plasma immersion ion implantation in radio frequency and ECR-microwave plasma system 2015 IEEE International Conference on Plasma Sciences, Antalya, Turkey, 24.-28.05.2015 H. Bhuyan, S. Mändl, M. Favre, M. Cisternas, A. Henriquez, E. Wyndham, M. Walczak, D. Manova Nitriding of super-ferritic stainless steel by plasma immersion ion implantation in radio frequency and microwave plasma system 17th International Conference on Materials Science and Engineering, Paris, France, 23.-24.01.2015 D. Breite, M. Went, N. Schönherr, A. Prager, A. Schulze Tailoring the surface charge for fouling resistant membranes Euromembrane 2015, Aachen, Germany, 06.-10.09.2015 M. Cisternas, A. Henriquez, H. Bhuyan, M. Retamal, M. Favre, U. Volkmann, D. Manova, S. Mändl, F. Guzman Formation and study of TiN coatings on titanium substrate using plasma immersion ion implanta- tion for applications in biological membranes DPG-Frühjahrstagung, Berlin, Germany, 15.-20.03.2015 T. Dankwort, U. Ross, J. Ditto, A.L. Hansen, M. Winkler, J. Koenig, W. Bensch, A. Lotnyk, L. Kienle Structure and stability of epitaxial superlattices of Bi2Te3 and Sb2Te3 thermoelectric thin films Microscopy Conference 2015, Göttingen, Germany, 06.-11.09.2015 M. Ehrhardt, P. Lorenz, L. Bayer, K. Zimmer Non-thermal laser patterning of functional thin-films by ablation of the thin-film-supporting carry foils International Conference on Advanced Laser Technologies ALT15, Faro, Portugal, 07.-11.09.2015 M. Fidan, S. Mändl, O. Öztürk Correlation of GIXRD with SIMS and SEM data for expanded austenite on austenitic stainless steel and CoCr 13th Int. Conf. on Plasma Based Ion Implantation, Buenos Aires, Argentina, 05.-09.10.2015 A. Finzel, J. W. Gerlach, A. Lotnyk, B. Rauschenbach Structural analysis of GaN films deposited on different Si substrates by hyperthermal ion-beam assisted molecular beam epitaxy Workshop Ionenstrahlen & Nanostrukturen, Heidelberg, Germany, 22.-24.07.2015 L. Fricke, C. Bundesmann, R. Fechner, M. Burkhardt, M. Helgert, A. Gatto, F. Frost, C. Sturm, R. Schmidt-Grund, M. Grundmann Mueller-Matrix-ellipsometry analysis of blazed gratings produced by reactive ion beam etching DPG-Frühjahrstagung, Berlin, Germany, 15.-20.03.2015 L. Fricke, C. Bundesmann, R. Fechner, M. Burkhardt, M. Helgert, A. Gatto, F. Frost, C. Sturm, R. Schmidt-Grund, M. Grundmann Mueller-Matrix-ellipsometry analysis of blazed gratings produced by reactive ion beam etching 9th European Workshop Ellipsometry, Twente, Netherland, 23.-25.02.2015 F. Haase, D. Manova, H. Kersten, S. Mändl Evidence of secondary electron emission during PIII pulses from thermoprobe measurements 13th Int. Conf. on Plasma Based Ion Implantation, Buenos Aires, Argentina, 05.-09.10.2015 107

Posters T. Scherzer, G. Mirschel, U. Helmstedt, L. Prager, U. Decker Monitoring of the degree of condensation in thin alkoxysiloaxane layers by NIR reflection spec- troscopy International Conference on Near Infrared Spectroscopy (NIR 2015), Foz do Iguaçu, Brazil, 18.-23.10.2015 A. Schulze, M. Went, A. Prager Membrane functionalization with hyperbranched polymers Euromembrane 2015, Aachen, Germany, 06.-10.09.2015 X. Sun, E. Thelander, J. W. Gerlach, U. Decker, D. Hirsch, B. Rauschenbach Effect of O-incorporation on structural transitions of PLD-deposited GeTe films Annual BuildMoNa Conference, Leipzig, Germany, 23.-24.03.2015 X. Sun, E. Thelander, J. W. Gerlach, U. Decker, B. Rauschenbach Pulsed laser deposited GeTe phase-change films on Silicon European Phase Change and Ovonics Symposium 2015, Amsterdam, Netherlands, 06.-08.09.2015 109