TY - GEN A1 - Hertwig, Andreas A1 - Martin, Sven A1 - Krüger, Jörg A1 - Spielmann, C. A1 - Lenner, M. A1 - Kautek, Wolfgang ED - Dausinger, F. ED - Lichtner, F. ED - Lubatschowski, H. T1 - Primary hazards and reliability of protective materials N2 - Femtosecond laser pulses are close to industrial use. The advantages of ultrashort laser pulses for micromachining applications especially in the case of dielectric and biological samples down to pulse durations of 5 fs have been established. The current international standards of laser safety are primarily concerned with CW and pulsed lasers down to the nanosecond range. Therefore, human tissue and laser-protection equipment was investigated with respect to its resistance and protection performance for femtosecond laser illumination down to 30 fs. This included filter glasses for laser protection eyewear, polymer and textile materials used in curtains and guards. Bulk absorber filters can provide enough protection against laser radiation, give a sufficiently broad absorption spectrum. Materials are damaged more easily by femtosecond laser radiation. The need for sufficient spectral broadness as well as the different damage thresholds have to be included in international laser safety standards. This work should trigger the development of novel eye-protection devices that are lighter and ergonomically more acceptable than present commercial models. KW - Lasersicherheit KW - Kurzpulslaser KW - Femtosekunden KW - Lasertechnik KW - Materialbearbeitung PY - 2004 SN - 3-540-20114-9 DO - https://doi.org/10.1007/b96440 SN - 0303-4216 N1 - Serientitel: Topics in applied physics – Series title: Topics in applied physics IS - 96 SP - 287 EP - 307 PB - Springer CY - Berlin AN - OPUS4-4661 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kautek, Wolfgang A1 - Pentzien, Simone A1 - Röllig, Mathias A1 - Rudolph, Pascale A1 - Krüger, Jörg A1 - Maywald-Pitellos, C. A1 - Bansa, H. A1 - Grösswang, H. A1 - König, E. T1 - Near-UV laser interaction with contaminants and pigments on parchment: laser cleaning diagnostics by SE-microscopy, VIS-, and IR-spectroscopy PY - 2000 SN - 1296-2074 SN - 1778-3674 VL - 1 IS - sup.1 PB - Elsevier CY - Paris AN - OPUS4-5981 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Paatsch, Wolfgang A1 - Kautek, Wolfgang A1 - Krüger, Jörg T1 - Structuring and Plating of Materials with Ultrashort Laser Pulses PY - 2000 SN - 0016-4232 VL - 91 IS - 5 SP - 1271 EP - 1275 PB - Leuze CY - Saulgau, Württ. AN - OPUS4-6000 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Baudach, Steffen A1 - Krüger, Jörg A1 - Kautek, Wolfgang T1 - Femtosecond Laser Processing of Soft Materials KW - Femtosecond pulse laser KW - Laser processing KW - Polymer ablation KW - Nanostructures PY - 2001 SN - 0387-0200 VL - 29 IS - 11 SP - 705 EP - 709 PB - Gakkai CY - Suita AN - OPUS4-6006 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Bonse, Jörn A1 - Baudach, Steffen A1 - Krüger, Jörg A1 - Kautek, Wolfgang ED - Exarhos, G. T1 - Femtosecond laser damage in dielectric coatings N2 - Multi-shot investigations of Ti:sapphire laser (wavelength (lambda) approximately equals 800 nm) induced damage were performed in three different laboratories (BAM, Berlin; LZH, Hannover; UNM, Albuquerque). The ablation behavior of a high reflecting mirror consisting of alternating (lambda) /4- layers of Ta2O5 and SiO2 was studied. Fused silica served as substrate. The influence of the pulse duration ((tau) equals 13 - 130 fs), the pulse number (30 - (infinity) ) and the repetition rate (10 Hz - 100 MHz) on the damage threshold will be discussed. T2 - 32nd Annual Boulder Damage Symposium CY - Boulder, CO, USA DA - 2000-10-16 PY - 2001 SN - 0-8194-4036-1 DO - https://doi.org/10.1117/12.425056 SN - 1605-7422 N1 - Serientitel: SPIE proceedings series – Series title: SPIE proceedings series IS - 4347 SP - 24 EP - 34 PB - International Society for Optical Engineering (SPIE) CY - Bellingham, Wash. AN - OPUS4-6013 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kautek, Wolfgang A1 - Pentzien, Simone A1 - Rudolph, Pascale A1 - Krüger, Jörg A1 - Maywald-Pitellos, C. A1 - Bansa, H. A1 - Grösswang, H. A1 - König, W. ED - Fotakis, C. T1 - Near-Ultraviolet Pulsed Laser Interaction with Contaminants and Pigments on Parchment: Spectroscopic Diagnostics for Laser Cleaning Safety T2 - 5th International Conference on Optics within Life Sciences CY - H¯erakleion, Greece DA - 1998-01-01 PY - 2000 SN - 3-540-66648-6 N1 - Serientitel: Optics within life sciences – Series title: Optics within life sciences IS - 5 SP - 100 EP - 107 PB - Springer CY - Berlin AN - OPUS4-6189 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Martin, Sven A1 - Hertwig, Andreas A1 - Lenzner, Matthias A1 - Krüger, Jörg A1 - Kautek, Wolfgang T1 - Spot-size dependence of the ablation threshold in dielectrics for femtosecond laser pulses N2 - The multi-pulse ablation threshold of barium borosilicate glass was measured using 30-fs pulses of a high repetition rate (1 kHz) laser system. The threshold fluence was found to decrease with increasing beam radius ranging from 20 to 400 m. Two existing models are applied by considering thermal accumulation and point defects, respectively . PY - 2003 DO - https://doi.org/10.1007/s00339-003-2213-6 SN - 0947-8396 VL - 77 IS - 7 SP - 883 EP - 884 PB - Springer CY - Berlin AN - OPUS4-6317 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krüger, Jörg A1 - Meja, P. A1 - Autric, M. A1 - Kautek, Wolfgang T1 - Femtosecond pulse laser ablation of anodic oxide coatings on aluminium alloys with on-line acoustic observation N2 - The 125-fs laser ablation behaviour (800 nm) of aluminium and anodic oxide coatings on an AlMgSi1 alloy was investigated. The multi-pulse ablation threshold of aluminium at 1.2 J cm-2 was less than that of the oxides of 2–3 J cm-2. Aluminium exhibited a single pulse modification (melting) threshold of 0.3 J cm-2. These values derived from an evaluation of the crater geometry coincided with on-line acoustic measurements. The detected microphone voltage amplitude increased linearly with the laser fluence. The morphology of the ablation craters on aluminium indicated melt formation and displacement of a homogeneous melt phase due to the recoil action of the expanding metal vapour. The laser-processed ceramic oxide phases, on the other hand, showed a spongy resolidified melt layer, which denotes a collocated in-depth formation both of a melt and a gas phase. These phenomena are discussed in terms of the relative dominance of penetration depth of laser light and heat affected zones in the investigated materials with strongly varying optical and thermodynamical properties. KW - Laser ablation KW - Acoustic measurement KW - Microphone KW - Aluminium KW - Aluminium oxide PY - 2002 SN - 0169-4332 SN - 1873-5584 VL - 186 IS - 1-4 SP - 374 EP - 380 PB - North-Holland CY - Amsterdam AN - OPUS4-6324 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bonse, Jörn A1 - Baudach, Steffen A1 - Krüger, Jörg A1 - Kautek, Wolfgang A1 - Lenzner, Matthias T1 - Femtosecond laser ablation of silicon-modification thresholds and morphology N2 - We investigated the initial modification and ablation of crystalline silicon with single and multiple Ti:sapphire laser pulses of 5 to 400 fs duration. In accordance with earlier established models, we found the phenomena amorphization, melting, re-crystallization, nucleated vaporization, and ablation to occur with increasing laser fluence down to the shortest pulse durations. We noticed new morphological features (bubbles) as well as familiar ones (ripples, columns). A nearly constant ablation threshold fluence on the order of 0.2 J/cm2 for all pulse durations and multiple-pulse irradiation was observed. For a duration of ,100 fs, significant incubation can be observed, whereas for 5 fs pulses, the ablation threshold does not depend on the pulse number within the experimental error. For micromachining of silicon, a pulse duration of less than 500 fs is not advantageous. PY - 2002 DO - https://doi.org/10.1007/s003390100893 SN - 0947-8396 VL - 74 IS - 1 SP - 19 EP - 25 PB - Springer CY - Berlin AN - OPUS4-6328 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jeschke, H.O. A1 - Garcia, M.E. A1 - Lenzner, Matthias A1 - Bonse, Jörn A1 - Krüger, Jörg A1 - Kautek, Wolfgang T1 - Laser ablation thresholds of silicon for different pulse durations: theory and experiment N2 - The ultrafast laser ablation of silicon has been investigated experimentally and theoretically. The theoretical description is based on molecular dynamics (MD) simulations combined with a microscopic electronic model. We determine the thresholds of melting and ablation for two different pulse durations =20 and 500 fs. Experiments have been performed using 100 Ti:Sap-phire laser pulses per spot in air environment. The ablation thresholds were determined for pulses with a duration of 25 and 400 fs, respectively. Good agreement is obtained between theory and experiment. KW - Laser ablation KW - Pulse duration KW - Threshold of silicon PY - 2002 DO - https://doi.org/10.1016/S0169-4332(02)00458-0 SN - 0169-4332 SN - 1873-5584 VL - 197-198 SP - 839 EP - 844 PB - North-Holland CY - Amsterdam AN - OPUS4-6314 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Friedrich, Jörg Florian A1 - Möller, B. A1 - Kühn, Gerhard A1 - Unger, Wolfgang A1 - Krüger, P. T1 - Improvement of adhesion properties of polymers by producing oxyfluorinated surfaces PY - 2001 SN - 0016-4232 VL - 92 IS - 5 SP - 1334 EP - 1444 PB - Leuze CY - Saulgau, Württ. AN - OPUS4-6973 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krüger, P. A1 - Knes, R. A1 - Friedrich, Jörg Florian T1 - Surface cleaning by plasma-enhanced desorption of contaminants PY - 1999 SN - 0257-8972 VL - 112 SP - 240 EP - 244 PB - Elsevier Science CY - Lausanne AN - OPUS4-6984 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, P. A1 - Friedrich, Jörg Florian A1 - Meyer-Plath, Asmus T1 - Gezielte chemische Funktionalisierung von porösen Materialien und Bauteilen aus der Mikrosystemtechnik T2 - Workshop Funktionalisierung von Oberflächen für die Biotechnologie CY - Dresden, Deutschland DA - 2003-03-11 PY - 2003 SP - 1(?) EP - 8(?) PB - EFDS CY - Dresden AN - OPUS4-6962 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, P. A1 - Friedrich, Jörg Florian A1 - Meyer-Plath, Asmus T1 - Selective chemical modification of porous materials and films for bio-medical applications T2 - CIP 2003 ; 14th International Colloquium on Plasma Processes CY - Antibes, France DA - 2003-06-30 PY - 2003 SP - 1(?) EP - 4(?) PB - sfv, Sociéte Française du Vide CY - Paris AN - OPUS4-6963 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Krüger, P. A1 - Friedrich, Jörg Florian ED - Mennig, G. T1 - Modifizierung von Polymeren im Niederdruckplasma T2 - 15. Fachtagung über Verarbeitung und Anwendung von Polymeren CY - Chemnitz, Deutschland DA - 1997-11-13 PY - 1997 SN - 3-00-001942-1 IS - B27 SP - 1 EP - 8 PB - Techn. Univ. CY - Chemnitz AN - OPUS4-6992 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, P. A1 - Wigant, L. A1 - Friedrich, Jörg Florian ED - Nowack, H. T1 - Permeabilitätsverminderung von Polyolefinfilmen durch Plasmapolymerbeschichtungen T2 - 5. Internationale Fachtagung - ND-Plasma-Technologie CY - Duisburg, Deutschland DA - 1997-09-22 PY - 1997 VL - 5 SP - 1(?) EP - 16(?) PB - Print-Service CY - Mülheim AN - OPUS4-6996 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, P. A1 - Friedrich, Jörg Florian T1 - Gezielte chemische Funktionalisierung von Polymermaterialien T2 - 4. Wörlitzer Workshop "Funktionelle Schichten" CY - Wörlitz, Deutschland DA - 2003-05-27 PY - 2003 VL - 4 SP - 1(?) EP - 7(?) PB - EFDS CY - Dresden AN - OPUS4-7289 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, Jörg T1 - Determination of a working range for the laser cleaning of soiled silk T2 - Konferenz LACONA VI, Lasers in the Conservation of Artworks CY - Vienna, Austria DA - 2005-09-21 PY - 2005 AN - OPUS4-7135 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mero, M. A1 - Clapp, B. A1 - Jasapara, J.C. A1 - Rudolph, W. A1 - Ristau, D. A1 - Starke, K. A1 - Krüger, Jörg A1 - Martin, Sven A1 - Kautek, Wolfgang T1 - On the damage behavior of dielectric films when illuminated with multiple femtosecond laser pulses N2 - The physical effects reducing the damage threshold of dielectric films when exposed to multiple femtosecond pulses are investigated. The measured temperature increase of a Ta2O5 film scales exponentially with the pulse fluence. A polarized luminescence signal is observed that depends quadratically on the pulse fluence and is attributed to twophoton excitation of self-trapped excitons that form after band-to-band excitation. The damage fluence decreases with increasing pulse number, but is independent of the repetition rate from 1 Hz to 1 kHz at a constant pulse number. The repetition rate dependence of the breakdown threshold is also measured for TiO2 , HfO2, Al2O3, and SiO2 films. A theoretical model is presented that explains these findings. KW - Laser-induced damage KW - Laser materials KW - Ultrafast phenomena KW - Coatings PY - 2005 DO - https://doi.org/10.1117/1.1905343 SN - 0892-354X VL - 44 IS - 5 SP - 051107-1-051107-7 PB - Dekker CY - New York, NY AN - OPUS4-7406 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kautek, Wolfgang A1 - Rudolph, Pascale A1 - Daminelli-Widany, Grazia A1 - Krüger, Jörg T1 - Physico-chemical aspects of femtosecond-pulse-laser-induced surface nanostructures N2 - Near-ablation threshold investigations focusing on the generation of periodic nanostructures and their correlation with physico-chemical properties of the solid phase such as e.g., the material-dependent surface energy, were conducted. Molecular dynamic modelling in the sub-picosecond time domain was used to consider ultrafast opto-electronic processes triggering surface reorganization reactions. Fluid containment of solid interfaces showed strong influence on the resulting micro- and nanostructures due to its drastic reduction of the surface energy. The phenomena are discussed in respect to the minimization of the surface free energy in dependence of material composition and interfacial structure. PY - 2005 DO - https://doi.org/10.1007/s00339-005-3211-7 SN - 0947-8396 VL - 81 SP - 65 EP - 70 PB - Springer CY - Berlin AN - OPUS4-7403 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krüger, Jörg A1 - Martin, Sven A1 - Mädebach, Heinrich A1 - Urech, L. A1 - Lippert, T. A1 - Wokaun, A. A1 - Kautek, Wolfgang T1 - Femto- and nanosecond laser treatment of doped polymethylmethacrylate N2 - Femto- and nanosecond laser ablation of polymethylmethacrylate (PMMA) and PMMA doped with a linear absorber was investigated in the infrared spectral region. Ablation thresholds were determined and incubation phenomena were identified. The ‘degree’ of incubation was calculated employing a phenomenological model. The influence of the pulse duration on the machining quality of the polymers was examined. The presence of an absorbing chromophore is not a prerequisite for a controllable fs-laser structuring in contrast to the ns-treatment. Surface swelling always accompanied ablation. KW - Laser ablation KW - Laser beam machining KW - Doping thin films KW - Polymers-radiation effects PY - 2005 DO - https://doi.org/10.1016/j.apsusc.2005.01.078 SN - 0169-4332 SN - 1873-5584 VL - 247 SP - 406 EP - 411 PB - North-Holland CY - Amsterdam AN - OPUS4-7470 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Starke, K. A1 - Ristau, D. A1 - Martin, Sven A1 - Hertwig, Andreas A1 - Krüger, Jörg A1 - Allenspacher, P. A1 - Riede, W. A1 - Meister, S. A1 - Theiss, C. A1 - Sabbah, A. A1 - Rudolph, W. A1 - Raab, V. A1 - Grigonis, R. A1 - Rakickas, T. A1 - Sirutkaitis, V. ED - Exarhos, G. J. T1 - Results of a round-robin experiment in multiple-pulse LIDT measurement with ultrashort pulses T2 - 35th Annual Boulder Damage Symposium ; 35th Annual Symposium on Optical Materials for High-Power Lasers CY - Boulder, CO, USA DA - 2003-09-22 KW - Multiple-pulse damage KW - ISO 11254-2 KW - S on 1-LIDT KW - Round-robin experiment KW - CHOCLAB PY - 2004 SN - 0-8194-5163-0 DO - https://doi.org/10.1117/12.525135 SN - 0038-7355 N1 - Serientitel: Proceedings of SPIE – Series title: Proceedings of SPIE IS - 5273 SP - 388 EP - 395 PB - SPIE, the International Society for Optical Engineering CY - Bellingham, Wash. AN - OPUS4-4948 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kautek, Wolfgang A1 - Hertwig, Andreas A1 - Martin, Sven A1 - Krüger, Jörg A1 - Lenzner, Matthias A1 - Spielmann, C. A1 - Lenner, M. A1 - Bunte, J. A1 - Puester, T. A1 - Burmester, T. A1 - Fiedler, A. A1 - Heberer, E. A1 - Brose, M. A1 - Stingl, A. A1 - Kiehl, P. A1 - Hönigsmann, H. A1 - Trautinger, F. A1 - Grabner, G. T1 - Safety in Femtosecond Laser Technology - Recent Results of a European Research Project (406) T2 - International Laser Safety Conference 2003 ; ILSC 2003 CY - Jacksonville, FL, USA DA - 2003-03-10 PY - 2003 SN - 0-912035-38-2 SP - 1(?) EP - 10(?) PB - Laser Institute of America CY - Orlando, Fla. AN - OPUS4-2259 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Daminelli-Widany, Grazia A1 - Krüger, Jörg A1 - Kautek, Wolfgang T1 - Femtosecond laser interaction with silicon under water confinement N2 - Femtosecond laser interaction with silicon was investigated in water and in air, with 130-fs laser pulses at 800 nm wavelength. Under water confinement, higher modification thresholds, lower ablation depths and similar incubation factors were found in comparison to the dry experiment. Morphological features of the laser-induced cavities also differed. In contrast to air experiments, debris redeposition was negligible, while the ablated material remained suspended in the water layer phase. Underwater cavities obtained at high fluences and high number of pulses per spot showed anomalous profiles, consistent with a strong spatial deformation of the laser beam coupled into the target. Ripples formed at the edges of the modified area showed varying spacings: f100 and f700 nm for water and air experiments, respectively. Differences to the air experiment were related to a complex combination of fluence-dependent non-linear effects occurring in the water layer and to pulse-number-dependent shielding effects induced by cavitation bubbles and suspended ablated material. KW - Laser ablation KW - Silicon KW - Solid electrolyte interface KW - Water PY - 2004 DO - https://doi.org/10.1016/j.tsf.2004.04.043 SN - 0040-6090 VL - 467 IS - 1-2 SP - 334 EP - 341 PB - Elsevier CY - Amsterdam AN - OPUS4-4008 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, Jörg T1 - Femto- and Nanosecond Laser Treatment of Doped Polymethylmethacrylate T2 - E-MRS 2004 Spring Meeting CY - Strasbourg, France DA - 2004-08-24 PY - 2004 AN - OPUS4-4145 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, Jörg T1 - Results of a round-robin experiment in multiple-pulse LIDT measurment with ultrashort pulses T2 - Boulder Damage Symposium CY - Boulder, CO, USA DA - 2003-09-22 PY - 2003 AN - OPUS4-5016 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krivenko, A.G. A1 - Kautek, Wolfgang A1 - Krüger, Jörg A1 - Benderskii, V.A. T1 - Subpicosecond Emission from Mercury and Silver into Electrolyte Solution: An Experimental Study PY - 1997 SN - 0038-5387 SN - 1023-1935 VL - 33 IS - 4 SP - 394 EP - 400 PB - MAIK Nauka/Interperiodica Publ. CY - Moscow AN - OPUS4-11781 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krivenko, A.G. A1 - Krüger, Jörg A1 - Kautek, Wolfgang A1 - Benderskii, V.A. T1 - Subpicosecond-Pulse-Laser-Induced Electron Emission from Mercury and Silver into Aqueous Electrolytes PY - 1995 SN - 0005-9021 VL - 99 IS - 12 SP - 1489 EP - 1494 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-11782 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 - GEN A1 - Kautek, Wolfgang A1 - Krüger, Jörg ED - Beyer, E. T1 - Femtosecond pulse laser ablation of metallic, semiconducting, ceramic, and biological materials N2 - Production of holes and grooves of < 30 micrometers diameter with high aspect ratio value is a delicate task either for mechanical tools, or for conventional nanosecond pulse lasers like e.g. pulsed Nd:YAG or excimer lasers. They later tend to cause microcracks extending from an annular melting zone, or substantial disruption, respectively. Experimental results are presented which demonstrate that the development of intense ultrashort pulse laser systems (>> 1012 W cm-2, (tau) < 1 ps) opens up possibilities for materials processing by cold plasma generation and ablation of metals, semiconductors, ceramics, composites, and biological materials. A femtosecond and a nanosecond dye laser with pulse durations of 300 fs (< 200 (mu) J) and 7 ns (< 10 mJ), and center wavelengths at 612 and 600 nm, respectively, both focused on an area of the order of 10-5 cm2, have been applied either to absorbing substrates, like polycrystalline gold, silicon (111), aluminum nitride ceramics, or transparent materials, like synthetic and human dental hydroxyapatite composites, bone material, and human cornea transplants. The fs-laser generates its own absorption in transparent materials by a multiphoton absorption process, and thus forces the absorption of visible radiation. Because the time is too short (< ps) for significant transport of mass and energy, the beam interaction generally results in the formation of a thin plasma layer of approximately solid state density. Only after the end of the subpicosecond laser pulse, it expands rapidly away from the surface without any light absorption and further plasma heating. Therefore, energy transfer (heat and impulse) to the target material, and thermal and mechanical disruption are minimized. In contrast to heat- affected zones (HAZ's) generated by conventional nanosecond pulse lasers of the order of 1 - 10 micrometers , HAZ's of less than 0.02 micrometers were observed. T2 - Conference on Production Line Processes ; Conference on Process Control and Modeling ; Conference on Novel Applications CY - Vienna, Austria DA - 1994-04-05 PY - 1994 SN - 0-8194-1508-1 DO - https://doi.org/10.1117/12.184768 SN - 1605-7422 N1 - Serientitel: SPIE proceedings series – Series title: SPIE proceedings series IS - 2207 SP - 600 EP - 611 PB - SPIE--the International Society for Optical Engineering CY - Bellingham, Wash. AN - OPUS4-11892 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Krüger, Jörg A1 - Kautek, Wolfgang A1 - Lenzner, M. A1 - Sartania, S. A1 - Spielmann, C. A1 - Krausz, F. ED - Dubowski, J. T1 - Structuring of dielectric and metallic materials with ultrashort laser pulses between 20 fs and 3 ps N2 - Laser-micromachining of barium aluminum borosilicate glass, fused silica and stainless steel has been extended down to a pulse duration of 20 fs generated by a Ti:sapphire laser system at a wavelength of 0.8 micrometer. A systematic study shows that, below 100 fs, an enhanced precision and a substantial decrease of the ablation threshold fluence in comparison to pulse laser processing with pulses in the picosecond and nanosecond range could be achieved. The physical mechanism and the technical relevance of this novel microtechnology is discussed. T2 - Conference CY - San José, CA, USA DA - 1997-02-10 KW - Ablation KW - Laser processing KW - Micromachining KW - Structuring KW - Femtosecond pulse laser KW - Glass KW - Silica KW - Steel PY - 1997 SN - 0-8194-2402-1 DO - https://doi.org/10.1117/12.273740 SN - 1605-7422 N1 - Serientitel: SPIE proceedings series – Series title: SPIE proceedings series IS - 2991 SP - 40 EP - 47 PB - SPIE CY - Bellingham, Wash. AN - OPUS4-11893 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Gruber, D. A1 - Husinsky, W. A1 - Grabner, G. A1 - Baumgartner, I. A1 - Scholman, J. A1 - Krüger, Jörg A1 - Kautek, Wolfgang ED - Waidelich, W. T1 - Nano- and Femtosecond-Laser Processing of Human Donor Corneal-Transplants and Lenticules for Corneal Surgery T2 - 12. Internationaler Kongress Laser 95 CY - Munich, Germany DA - 1995-06-01 PY - 1996 SN - 3-540-61316-1 SP - 397 EP - 400 PB - Springer CY - Berlin AN - OPUS4-11895 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 - CONF A1 - Krüger, Simone A1 - Schulze, Rolf-Dieter A1 - Brademann-Jock, Kerstin A1 - Friedrich, Jörg Florian ED - Pershin, L. T1 - Introduction of irregularities into plasma polymers by radiative and auto-oxidative processes T2 - 17th International Symposium on Plasma Chemistry (ISPC-17) CY - Toronto, Canada DA - 2005-08-07 PY - 2005 SP - 1(?) EP - 6(?) CY - Toronto AN - OPUS4-11943 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Krüger, Jörg A1 - Kautek, Wolfgang A1 - Staub, M. A1 - Scherer, G.G. ED - Waidelich, W. T1 - Femtosecond-pulse laser micromachining of metal layer composites T2 - 12. Internationalen Kongresses Laser 95 CY - Berlin, Germany DA - 1996-01-01 PY - 1996 SN - 3-540-61316-1 SP - 966 EP - 969 PB - Springer CY - Berlin AN - OPUS4-11958 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - von Woedtke, T. A1 - Abel, P. A1 - Schröder, K. A1 - Schwock, A. A1 - Krüger, Jörg A1 - Kautek, Wolfgang T1 - Biosensor-Membranen mit "Analyt-Fenster" T2 - 8. Internationale Messe mit Kongreß für Sensoren, Meßaufnehmer & Systeme ; 8th International Fair with Congress for Sensors, Transducers & Systems CY - Nürnberg, Deutschland DA - 1997-05-13 PY - 1997 VL - 2 SP - 101 EP - 106 PB - ACS Organisations GmbH CY - Wunstorf AN - OPUS4-11959 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Niino, Hiroyuki A1 - Krüger, Jörg A1 - Kautek, Wolfgang ED - Dubowski, J. ED - Dyer, P. T1 - Photochemical surface modification of polyurethane films with biomaterial by excimer laser processing T2 - 3rd Three-Day Conference on Laser Applications in Microelectronic and Optoelectronic Manufacturing, LAMOM ; LASE ; Photonics West CY - San José, CA, USA DA - 1998-01-26 KW - Laser irradiation surface effects KW - Surface and interface chemistry of polymers KW - Photochemical reactions of biomolecules KW - Biochemical reaction mechanisms and kinetics PY - 1998 SN - 0-8194-2713-6 SN - 1605-7422 N1 - Serientitel: SPIE proceedings series – Series title: SPIE proceedings series IS - 3274 SP - 128 EP - 132 PB - SPIE CY - Bellingham, Wash. AN - OPUS4-12040 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Boeck, T. A1 - Schmidt, K. A1 - Lorenz, M. A1 - Rosenfeld, A. A1 - Rudolph, Pascale A1 - Krüger, Jörg A1 - Kautek, Wolfgang ED - Gobrecht, J. T1 - Ultra-short pulse laser seeding techniques for silicon crystallite growth on amorphous substrates T2 - QUANTSOL 99 CY - Wildhaus, Switzerland DA - 1999-03-14 PY - 1999 SP - 1(?) EP - 3(?) AN - OPUS4-12041 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Lenzner, M. A1 - Sartania, S. A1 - Spielmann, C. A1 - Krausz, F. A1 - Krüger, Jörg A1 - Kautek, Wolfgang T1 - Nanometer precision material ablation and optical breakdown with sub-10 fs pulses T2 - 11th International Conference on Ultrafast Phenomena CY - Garmisch-Partenkirchen, Germany DA - 1998-07-12 PY - 1998 SN - 3-540-65430-5 SN - 0172-6218 N1 - Serientitel: Springer Series in chemical physics – Series title: Springer Series in chemical physics IS - 63 SP - 313 EP - 315 PB - Springer CY - Heidelberg AN - OPUS4-12042 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Lenzner, M. A1 - Sartania, S. A1 - Spielmann, C. A1 - Krausz, F. A1 - Krüger, Jörg A1 - Kautek, Wolfgang T1 - Optical Damage of Dielectrics down to 5 fs T2 - 17th Conference on Lasers and Electro-Optics (CLEO) CY - Baltimore, MD, USA DA - 1997-05-18 PY - 1997 SN - 1-557-52498-X IS - 11 SP - 218 EP - 219 PB - Optical Society of America CY - Washington, DC AN - OPUS4-12043 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, Jörg T1 - Sicherheitsaspekte bei der Nutzung von Laserstrahlung T2 - 11. Salzburger Ophthalmologisches Symposium CY - Salzburg, Austria DA - 2006-04-07 PY - 2006 AN - OPUS4-12203 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, Jörg T1 - Femtosecond laser-induced damage of gold films T2 - E-MRS 2006 Spring Meeting, Symposium H CY - Nice, France DA - 2006-05-29 PY - 2006 AN - OPUS4-12252 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, Jörg T1 - Ultrakurze Laserimpulse in der Mikromaterialbearbeitung T2 - Tag der Technik, Fachhochschule für Technik und Wirtschaft (FHTW) CY - Berlin, Germany DA - 2006-05-19 PY - 2006 AN - OPUS4-12305 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Urech, L. A1 - Lippert, T. A1 - Wokaun, A. A1 - Martin, Sven A1 - Mädebach, Heinrich A1 - Krüger, Jörg T1 - Removal of doped poly(methylmetacrylate) from tungsten and titanium substrates by femto- and nanosecond laser cleaning N2 - The influence of different laser pulse lengths on the removal of a polymer layer from metal substrates was investigated. As model systems, doped poly(methylmetacrylate) (PMMA) on titanium and tungsten substrates were selected. The ablation threshold and irradiation spot morphology of titanium and tungsten were compared for femtosecond (fs) and nanosecond (ns) laser irradiation and different pulse numbers. Nanosecond laser treatment resulted in a non-homogeneous surface morphology for both titanium and tungsten substrates. Femtosecond irradiation of tungsten revealed a homogeneous ablation spot with little changes in the surface morphology. For titanium, the formation of columnar structures within the irradiation spot was observed. Two different dopant concentrations were used for PMMA to achieve an equal linear absorption coefficient for the femto- and nanosecond laser wavelengths of 790 and 1064 nm. The best results were achieved for the removal of doped PMMA by femtosecond laser irradiation, where only a minimal modification of the metal surface was detected. In the case of nanosecond laser exposure, a pronounced change of the structure was observed, suggesting that damage-free cleaning of the selected metal may only be possible using femtosecond laser pulses. Different experimental parameters, such as laser fluence, pulse repetition rate and sample speed were also investigated to optimize the cleaning quality of doped PMMA from tungsten substrates with femtosecond laser pulses. KW - Poly(methylmetacrylate) KW - Laser treatment KW - Tungsten KW - Titanium KW - Femtosecond PY - 2006 DO - https://doi.org/10.1016/j.apsusc.2005.07.109 SN - 0169-4332 SN - 1873-5584 VL - 252 IS - 13 SP - 4754 EP - 4758 PB - North-Holland CY - Amsterdam AN - OPUS4-12368 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krüger, Simone A1 - Schulze, Rolf-Dieter A1 - Brademann-Jock, Kerstin A1 - Swaraj, Sufal A1 - Friedrich, Jörg Florian T1 - Charakterisierung von Plasmapolymeren mittels Thermolumineszenzmessungen N2 - Dünne, mit einem gepulsten Plasma hergestellte Polymerschichten wurden untersucht. Diese Plasmapolymere sollten eine chemisch besser definierte Struktur haben, weil der Anteil an rein chemisch polymerisiertem Produkt während der Plasma-aus-Zeit steigen sollte, während der Anteil an Schichtbildung, der innerhalb der kurzen Plasmapulse durch Monomerfragmentierung und statistische Polyrekombination erzeugt wird, zurückgedrängt wird. Der Monomerfragmentierungsprozeß ist im kontinuierlich brennenden Plasma (cw-Mode) demgegenüber der Hauptprozeß. Neben der Anwendung der klassischen Element- und Bindungsanalysentechnik XPS (X-ray Photoelectron Spectroscopy) wurden hier die Schichten auch mittels Thermolumineszenz untersucht. Defekte und Strukturanomalitäten in Polymeren sollten mit dieser Methode charakterisiert werden können. Untersuchungsobjekte waren funktionalgruppentragende Plasmapolymerschichten, die biosensorische oder biokompatible Funktionen besitzen oder als Haftvermittler in Metall-Polymercompositen eingesetzt werden. Translated Abstract Characterization of Plasmapolymers by Thermoluminescence Thin plasma polymer films were deposited using the pulsed plasma (pp) mode. These plasma polymers should possess a more chemically regular structure because of the lower monomer fragmentation during the short plasma pulses and the chemical chain propagation during the plasma-less periods than those produced by the conventional continuous-wave (cw) mode. In addition to the use of the classic thin film characterization method XPS the method of thermoluminescence was applied to characterize defects and structural specifics in the polymer films produced by pp or cw-plasma mode. The thermoluminescence method was applied to functional groups-carrying plasma polymer layers, which are used in medical technology for forming biocompatible and bioactive coatings or in metal-polymer composites as adhesion-promoting interlayers. KW - Plasmapolymere KW - Thermolumineszenz KW - X-ray PY - 2006 DO - https://doi.org/10.1002/vipr.200600287 SN - 0947-076X SN - 1522-2454 VL - 18 IS - 3 SP - 32 EP - 37 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-12514 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krüger, Simone A1 - Schulze, Rolf-Dieter A1 - Brademann-Jock, Kerstin A1 - Swaraj, Sufal A1 - Friedrich, Jörg Florian T1 - Characterisation of plasma polymers by thermoluminescence N2 - Thin plasma polymer films were deposited using the pulsed plasma mode. These plasma polymers should possess a more regular structure than those produced by the conventional continuous-wave (cw) mode, because of lower monomer fragmentation caused by the plasma pulses and the chemical chain propagation during the plasmaless (free!) periods. The thermoluminescence method was applied to functional groups carrying plasma polymer layers which are used in medical technology. Examples are formation of biocompatible, biosensoric and bioactive coatings or in metal polymer composites such as adhesion-promoting interlayers. In addition to the use of the conventional X-ray Photoelectron Spectroscopy for thin film characterization, the new method of thermoluminescence was applied to characterize undesired defects and structural specifics produced in the polymer films by pp or cw plasma mode. The main areas of focus were oxygen-containing groups produced by post-plasma oxygen introduction via auto-oxidation, oxidation of implemented unsaturations and trapped radical sites known as typical irregular structures in plasma polymers. KW - Plasma polymers KW - Thermoluminescence KW - Structure KW - Defects KW - Pulsed plasma KW - Continuous-wave plasma PY - 2006 DO - https://doi.org/10.1016/j.surfcoat.2005.12.003 SN - 0257-8972 VL - 201 IS - 3-4 SP - 543 EP - 552 PB - Elsevier Science CY - Lausanne AN - OPUS4-12818 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hertwig, Andreas A1 - Martin, Sven A1 - Krüger, Jörg A1 - Kautek, Wolfgang T1 - Interaction area dependence of the ablation threshold of ion-doped glass N2 - The laser ablation behaviour of ion-doped glass filter materials under irradiation with femtosecond laser pulses was investigated with respect to spot size and repetition rate. The damage threshold fluence of Schott BG18 depends on the size of the irradiated area. The effect is discussed in terms of a defect-site model. KW - Femtosecond KW - Laser KW - Materials processing KW - Ablation KW - Threshold KW - Glass PY - 2004 DO - https://doi.org/10.1016/j.tsf.2003.11.131 SN - 0040-6090 VL - 453-454 SP - 527 EP - 530 PB - Elsevier CY - Amsterdam AN - OPUS4-11046 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hertwig, Andreas A1 - Martin, Sven A1 - Krüger, Jörg A1 - Kautek, Wolfgang T1 - Surface damage and color centers generated by femtosecond pulses in borosilicate glass and silica N2 - Color center generation by femtosecond laser pulses (30 fs) is observed in a fluence range below the damage threshold in an alkali-free barium borosilicate (BBS) glass, and in a thin layer of SiO2 on a fused silica substrate. The color centers are characterized spectroscopically. The optical density of the color centers in BBS glass is by two orders of magnitude higher than that in silica. A healing process with a time constant of about 30 h can be found. PY - 2004 UR - http://www.sciencedirect.com/science/journal/0926860X DO - https://doi.org/10.1007/s00339-004-2634-x SN - 0947-8396 VL - 79 SP - 1075 EP - 1077 PB - Springer CY - Berlin AN - OPUS4-11047 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krüger, Jörg A1 - Kautek, Wolfgang T1 - Femtosecond-pulse visible laser processing of transparent materials N2 - High-power lasers in industrial and R & D applications raise the general problem of reliability and degradation of optical components. A systematic study of nonlinear interaction of various transparent dielectric materials as e.g. glasses, fused silica, and polymers, with laser-pulses in the intensity range of up to 1013 W cm-2 is presented. On the other hand, femtosecond-pulse laser processing in the visible spectral range (300 fs; 620 nm, ~ 2 eV) allows precise microstructuring of transparent dielectrics without disruption of the remnant material. Damage and ablation threshold fluences occur above 1.2 J cm-2 at both silicate glasses and fused silica. Two different photon absorption mechanisms have been observed. The first occurs during the initial laser pulses in the incubation range. There, multiphoton absorption results in moderate energy volume densities. These are sufficient to generate morphological changes and optically active defect sites (colour centres) which provide a much higher absorptivity relevant for the second mechanism. It results in gasification without participation of melt. PY - 1996 SN - 0169-4332 SN - 1873-5584 VL - 96-98 SP - 430 EP - 438 PB - North-Holland CY - Amsterdam AN - OPUS4-11509 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - v. Woedtke, T. A1 - Abel, P. A1 - Krüger, Jörg A1 - Kautek, Wolfgang T1 - Subpicosecond-pulse laser microstructuring for enhanced reproducibility of biosensors N2 - Curved substrates can be micro-structured by laser ablation, which is not possible with standard lithographic methods. The novel femtosecond-pulse laser technique allows the production of defined and reproducible micro-perforations of originally analyte-impermeable membranes. The trans-membrane analyte flux can be controlled both by the variation of the laser focus diameter resulting in different areas of single perforations, and the number of perforations in arrays on small membrane areas. This leads to a higher degree of variability as well as reproducibility of the diffusion qualities of sensor membranes, and marks the main innovation with this technique compared to the hand-made mechanical perforation by specially grinded needles used up to now. Touchless micro-perforation of small membrane areas with negligible heat damage of the structures adjacent to the perforation allows the application of ‘analyte door’ membranes directly onto curved surfaces of miniaturized needle-sensors assigned for in vivo glucose monitoring, for the first time. KW - Biosensor KW - Glucose KW - Membrane perforation KW - Subpicosecond laser ablation KW - Reproducibility PY - 1997 DO - https://doi.org/10.1016/S0925-4005(97)80330-9 SN - 0925-4005 SN - 1873-3077 VL - 42 IS - 3 SP - 151 EP - 156 PB - Elsevier CY - Amsterdam [u.a.] AN - OPUS4-11513 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -