TY - CONF A1 - Kautek, Wolfgang A1 - Pentzien, Simone ED - Dickmann, K. T1 - Laser Cleaning System for Automated Paper and Parchment Cleaning T2 - Laser in the Conservation of Artworks - LACONA CY - Osnabrück, Germany DA - 2005-09-15 PY - 2005 SN - 3-540-22996-5 SN - 0930-8989 N1 - Serientitel: Springer proceedings in physics – Series title: Springer proceedings in physics IS - 100 SP - 403 EP - 410 PB - Springer CY - Berlin AN - OPUS4-6874 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kautek, Wolfgang A1 - Pentzien, Simone A1 - Krüger, Jörg A1 - König, E. ED - Kautek, W. ED - König, E. T1 - Laser cleaning of ancient parchments T2 - LACONA I CY - Heraklion, Crete, Greece DA - 1995-10-04 PY - 1997 SN - 3-901025-68-5 VL - 18 SP - 69 EP - 78 PB - Mayer CY - Klosterneuburg AN - OPUS4-11784 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Daminelli-Widany, Grazia A1 - Pentzien, Simone A1 - Hertwig, Andreas A1 - Krüger, Jörg T1 - Influence of film thickness on laser ablation of hydrogenated amorphous carbon films N2 - Single-pulse damage thresholds of hydrogenated amorphous carbon (a-C:H) films were measured for 8-ns laser pulses at 532-nm wavelength. Layer thicknesses from below the optical penetration depth to above the thermal diffusion length (60 nm–13 µm) were examined. After correction of the damage-threshold values for the fraction of energy effectively absorbed by the material, the damage threshold was found to increase linearly with the layer thickness, also for film thicknesses below the optical penetration depth of a-C:H. The threshold fluence reached the bulk value for a layer thickness equal to the thermal diffusion length. The thermal diffusion coefficient was obtained from fitting the experimental data. Several phenomena like graphitization, blistering, exfoliation, and ablation were observed for different fluence regimes and film thicknesses. PY - 2006 DO - https://doi.org/10.1007/s00339-005-3460-5 SN - 0340-3793 VL - 83 IS - 1 SP - 89 EP - 94 PB - Springer CY - Berlin AN - OPUS4-12022 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kautek, Wolfgang A1 - Pentzien, Simone A1 - Rudolph, Pascale A1 - Krüger, Jörg A1 - König, E. T1 - Laser interaction with coated collagen und cellulose fibre composites: fundamentals of laser cleaning of ancient parchment manuscripts and paper N2 - Laser cleaning of delicate biological composite materials such as ancient parchment manuscripts from the 15th and 16th century and printed paper from the 19th century is demonstrated with an ultraviolet excimer pulsed laser at 308 nm. Laser fluence levels must stay below the ablation and destruction threshold of the parchment or paper substrate, and have to surpass the threshold of the contaminant matter. Foreign layers to be removed must exhibit a higher optical density than the artifact substrates. Synthetic carbonaceous dirt modelled by water-soluble black crayons showed a characteristically weak featureless laser-induced plasma spectroscopy spectrum near the noise limit. It turned out that laser-induced plasma spectroscopy is of limited use in monitoring halting points (or etch-stops) because it relies on the destruction not only of the laterally inhomogenously distributed contaminant but also of pigment phases on a microscopically rough parchment substrate. Laser-induced fluorescence spectroscopy, however, promises to be a valuable non-destructive testing technique for etch-stop monitoring. KW - Laser KW - Parchment KW - Papery KW - Spectroscopy KW - Laser cleaning PY - 1998 SN - 0169-4332 SN - 1873-5584 VL - 127-129 SP - 746 EP - 754 PB - North-Holland CY - Amsterdam AN - OPUS4-11516 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wurster, R. A1 - Pentzien, Simone A1 - Conradi, Andrea A1 - Krüger, Jörg T1 - Characterization of laser-generated microparticles by means of a dust monitor and SEM imaging N2 - Nanosecond laser (1064 nm wavelength) cleaning of artificially soiled paper as a model sample simulating a real-world artwork was performed. During the cleaning process, the ejection of particles was monitored in situ by means of a dust monitor (8 size classes, ranging from 0.3 µm to >2 µm) and ex situ using a mini-cascade impactor (MKI, 5 stages). The cleaning result was analyzed by scanning electron microscopy (SEM) considering possible laser-induced damages to the substrate. Size distributions of emitted particles were measured depending on the processing parameters: laser fluence, F, and pulse number per spot, N. High numbers of large (>2 µm) particles were collected by the mini-cascade impactor indicating a gas dynamical liftoff process. Obviously, these particles were not affected by the laser-matter interaction. The different methods (SEM, MKI, and dust monitor) are compared with respect to their usefulness for a proper interpretation of the cleaning results. PY - 2006 DO - https://doi.org/10.1155/2006/31862 SN - 0278-6273 SN - 1476-3516 VL - 2006 IS - Article ID 31862 SP - 1 EP - 5(?) PB - Harwood Academic Publ. CY - London AN - OPUS4-14467 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mäder, M. A1 - Holle, H. A1 - Schreiner, M. A1 - Pentzien, Simone A1 - Krüger, Jörg A1 - Kautek, Wolfgang ED - Johann Nimmrichter, ED - Kautek, Wolfgang ED - Manfred Schreiner, T1 - Traditional and laser cleaning methods of historic picture post cards T2 - LACONA VI CY - Vienna, Austria DA - 2005-09-21 KW - Laser KW - Cleaning KW - Picture Post Card PY - 2007 SN - 978-3-540-72129-1 SN - 0930-8989 N1 - Serientitel: Springer proceedings in physics – Series title: Springer proceedings in physics IS - 116 SP - 281 EP - 286 PB - Springer CY - Berlin AN - OPUS4-16378 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lerber, K. von A1 - Strlic, M. A1 - Kolar, J. A1 - Krüger, Jörg A1 - Pentzien, Simone A1 - Kennedy, C. A1 - Wess, T. A1 - Sokhan, M. A1 - Kautek, W. ED - Johann Nimmrichter, ED - Kautek, Wolfgang ED - Manfred Schreiner, T1 - Laser cleaning of undyed silk: Indications of chemical change T2 - LACONA VI CY - Vienna, Austria DA - 2005-09-21 KW - Laser KW - Cleaning KW - Silk KW - Textiles KW - Viscometry KW - X-ray diffraction KW - SIMS PY - 2007 SN - 978-3-540-72129-1 SN - 0930-8989 N1 - Serientitel: Springer proceedings in physics – Series title: Springer proceedings in physics IS - 116 SP - 313 EP - 319 PB - Springer CY - Berlin AN - OPUS4-16379 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, Jörg A1 - Pentzien, Simone A1 - Lerber, K. von ED - Johann Nimmrichter, ED - Kautek, Wolfgang ED - Manfred Schreiner, T1 - Determination of a working range for the laser cleaning of soiled silk T2 - LACONA VI CY - Vienna, Austria DA - 2005-09-21 KW - Laser KW - Cleaning KW - Silk KW - Textiles PY - 2007 SN - 978-3-540-72129-1 SN - 0930-8989 N1 - Serientitel: Springer proceedings in physics – Series title: Springer proceedings in physics IS - 116 SP - 321 EP - 327 PB - Springer CY - Berlin AN - OPUS4-16380 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eberstein, M. A1 - Geier, M. A1 - Grießmann, H. A1 - Partsch, U. A1 - Voelkel, L. A1 - Böhme, R. A1 - Pentzien, Simone A1 - Koter, Robert A1 - Mann, Guido A1 - Bonse, Jörn A1 - Krüger, Jörg T1 - Towards an industrial laser doping process for the selective emitter using phosphoric acid as dopant N2 - Different laser supported approaches have already been realized, proving the great potential of laserdoped selective emitters (LDSE). However, it is challenging to establish a low-cost process by using pulsed laser tools. So far a single-step process only leads to satisfying results utilizing cw-lasers. In this paper we have examined a two-step process to produce laser-doped selective emitters on multicrystalline textured standard silicon photovoltaic wafers (90-Ω/sq-Emitter, SiN-antireflection coating (ARC)). The precise ARC removal by near-infrared fs-laser pulses (30 fs, 800 nm), and the doping of uncoated silicon wafers by ns-laser pulses (8 ns, 532 nm) were systematically investigated. In the fs-experiment, optimum conditions for ARC removal were identified. In the nsexperiments under suitable conditions (melting regime), the phosphorous concentration underneath the wafer surface was significantly increased and the sheet resistance was reduced by nearly a factor of two. Moreover, electrical measurements on fired metallization fingers deposited on the laser processed wafers showed low contact resistances. Hence, wafer conditioning with combined fs-laser- and ns-laser-processes are expected to be a promising technology for producing selective emitters. T2 - 26th European photovoltaic solar energy conference and exhibition CY - Hamburg, Germany DA - 05.09.2011 KW - Laser processing KW - Doping KW - Selective emitter KW - Multicrystalline silicon PY - 2011 SN - 3-936338-27-2 DO - https://doi.org/10.4229/26thEUPVSEC2011-2BV.1.2 SP - 1220 EP - 1223 AN - OPUS4-24996 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kotsifaki, D.G. A1 - Zekou, L. A1 - Pentzien, Simone A1 - Krüger, Jörg A1 - Serafetinides, A.A. ED - Saunders, D. ED - Strlic, M. ED - Korenberg, C. ED - Luxford, N. ED - Birkhölzer, K. T1 - Cleaning of artificially soiled papers by infrared and mid-infrared lasers N2 - One of the most important materials presenting and witnessing human culture is paper. The cleaning of paper is often necessary because contamination must be removed so that the fragile organic substrate can be preserved. The conventional cleaning methods are mechanical or involve the application of chemicals. These methods can damage drawings or print layers to some extent or make the original paper substrate brittle. More specifically, the use of a scalpel blade can cause damage to fibers. Chemical cleaning is difficult to perform locally, can dissolve foreign matter that then migrates into the paper substrate, or involves volatile organic compounds that can be harmful to the conservator. There is, therefore, a need for new conservation technologies aimed at the safe cleaning of paper. Lasers have proved to be an appropriate tool for cleaning as the energy dose and penetration depth at the specific point of contamination can be controlled. Additionally, if used properly, laser cleaning is not destructive to the paper. T2 - LACONA IX - Lasers in the conservation of artworks CY - London, UK DA - 07.09.2011 KW - Laser cleaning KW - Paper KW - Artificial soiling KW - Nanosecond laser KW - Microsecond laser PY - 2013 SN - 978-1-904982-87-6 SP - 219 EP - 221 PB - Archetype publications Ltd. AN - OPUS4-27956 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -