TY - JOUR A1 - Rosenfeld, A. A1 - Rohloff, M. A1 - Höhm, S. A1 - Krüger, Jörg A1 - Bonse, Jörn T1 - Formation of laser-induced periodic surface structures on fused silica upon multiple parallel polarized double-femtosecond-laser-pulse irradiation sequences JF - Applied surface science N2 - The formation of laser-induced periodic surface structures (LIPSS) upon irradiation of fused silica with multiple irradiation sequences of parallel polarized Ti:sapphire femtosecond laser pulse pairs (160 fs pulse duration, 800 nm central wavelength) was studied experimentally. For that purpose, a Michelson interferometer was used to generate near-equal-energy double-pulse sequences allowing the temporal pulse delay between the parallel-polarized individual fs-laser pulses to be varied between 0 and 40 ps with ~0.2 ps temporal resolution. The surface morphologies of the irradiated surface areas were characterized by means of scanning electron and scanning force microscopy. In the sub-ps delay range a strong decrease of the LIPSS periods and the ablation crater depths with the double-pulse delay was observed indicating the importance of the laser-induced free-electron plasma in the conduction band of the solids for the formation of LIPSS. KW - Laser-induced periodic surface structures (LIPSS) KW - Femtosecond laser ablation KW - Double-pulse experiments KW - Fused silica KW - Michelson interferometer PY - 2012 DO - https://doi.org/10.1016/j.apsusc.2011.09.076 SN - 0169-4332 SN - 1873-5584 VL - 258 IS - 23 SP - 9233 EP - 9236 PB - North-Holland CY - Amsterdam AN - OPUS4-26226 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Höhm, S. A1 - Rohloff, M. A1 - Rosenfeld, A. A1 - Krüger, Jörg A1 - Bonse, Jörn T1 - Dynamics of the formation of laser-induced periodic surface structures on dielectrics and semiconductors upon femtosecond laser pulse irradiation sequences JF - Applied physics A N2 - The formation of laser-induced periodic surface structures (LIPSS) upon irradiation of fused silica and silicon with multiple (NDPS) irradiation sequences consisting of linearly polarized femtosecond laser pulse pairs (pulse duration ~150 fs, central wavelength ~800 nm) is studied experimentally. Nearly equal-energy double-pulse sequences are generated allowing the temporal pulse delay Δt between the cross-polarized individual fs-laser pulses to be varied from -40 ps to +40 ps with a resolution of ~0.2 ps. The surface morphologies of the irradiated surface areas are characterized by means of scanning electron and scanning force microscopy. Particularly for dielectrics in the sub-ps delay range striking differences in the orientation and spatial characteristics of the LIPSS can be observed. For fused silica, a significant decrease of the LIPSS spatial periods from ~790 nm towards ~550 nm is demonstrated for delay changes of less than ~2 ps. In contrast, for silicon under similar irradiation conditions, the LIPSS periods remain constant (~760 nm) for delays up to 40 ps. The results prove the impact of laser-induced electrons in the conduction band of the solid and associated transient changes of the optical properties on fs-LIPSS formation. PY - 2013 DO - https://doi.org/10.1007/s00339-012-7184-z SN - 0947-8396 VL - 110 IS - 3 SP - 553 EP - 557 PB - Springer CY - Berlin AN - OPUS4-27787 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bonse, Jörn A1 - Höhm, S. A1 - Rosenfeld, A. A1 - Krüger, Jörg T1 - Sub-100-nm laser-induced periodic surface structures upon irradiation of titanium by Ti:sapphire femtosecond laser pulses in air JF - Applied physics A N2 - The formation of laser-induced periodic surface structures (LIPSS) on titanium upon irradiation with linearly polarized femtosecond (fs) laser pulses (τ = 30 fs, λ = 790 nm) in an air environment is studied experimentally and theoretically. In the experiments, the dependence on the laser fluence and the number of laser pulses per irradiation spot has been analyzed. For a moderate number of laser pulses (N < 1000) and at fluences between ~0.09 and ~0.35 J/cm², predominantly low-spatial-frequency-LIPSS with periods between 400 nm and 800 nm are observed perpendicular to the polarization. In a narrow fluence range between 0.05 and 0.09 J/cm², high-spatial-frequency-LIPSS with sub-100-nm spatial periods (~λ/10) can be generated with an orientation parallel to the polarization (N = 50). These experimental results are complemented by calculations based on a theoretical LIPSS model and compared to the present literature. PY - 2013 DO - https://doi.org/10.1007/s00339-012-7140-y SN - 0947-8396 VL - 110 IS - 3 SP - 547 EP - 551 PB - Springer CY - Berlin AN - OPUS4-27788 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krüger, Jörg A1 - Lenzner, Matthias A1 - Martin, Sven A1 - Lenner, M. A1 - Spielmann, Ch. A1 - Fiedler, A. A1 - Kautek, Wolfgang T1 - Single- and multi-pulse femtosecond laser ablation of optical filter materials JF - Applied surface science N2 - Ablation experiments employing Ti:sapphire laser pulses with durations from 30 to 340 fs (centre wavelength 800 nm, repetition rate 1 kHz) were performed in air. Absorbing filters (Schott BG18 and BG36) served as targets. The direct focusing technique was used under single- and multi-pulse irradiation conditions. Ablation threshold fluences were determined from a semi-logarithmic plot of the ablation crater diameter versus laser fluence. The threshold fluence decreases for a shorter pulse duration and an increasing number of pulses. The multi-pulse ablation threshold fluences are similar to those of undoped glass material (~1 J cm-2). That means that the multi-pulse ablation threshold is independent on the doping level of the filters. For more than 100 pulses per spot and all pulse durations applied, the threshold fluence is practically constant. This leads to technically relevant ablation threshold values. KW - Damage KW - Femtosecond laser ablation KW - Filter KW - Incubation KW - Laser safety KW - Threshold PY - 2003 DO - https://doi.org/10.1016/S0169-4332(02)01389-2 SN - 0169-4332 SN - 1873-5584 VL - 208-209 SP - 233 EP - 237 PB - North-Holland CY - Amsterdam AN - OPUS4-11545 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Martin, Sven A1 - Krüger, Jörg A1 - Hertwig, Andreas A1 - Fiedler, A. A1 - Kautek, Wolfgang T1 - Femtosecond laser interaction with protection materials JF - Applied surface science N2 - Textile, aluminium and polyethylene used as components in laser protection curtains were investigated with respect to their ablation behaviour. Employing 33-fs pulses (800 nm wavelength, 1 kHz repetition rate), ex situ geometrical measurements of the ablation cavities and in situ acoustic investigations with a microphone were performed to determine the ablation thresholds in the single- and multi-pulse cases. The acoustical method proved advantageous for complex surface morphologies and/or single laser pulse interactions. Incubation phenomena can be observed for all the materials studied. Technically relevant multi-pulse ablation thresholds are presented and are compared with the single-pulse (1-on-1) irradiation. KW - Damage KW - Femtosecond laser ablation KW - Laser safety KW - Threshold KW - Aluminium KW - Textile PY - 2003 DO - https://doi.org/10.1016/S0169-4332(02)01392-2 SN - 0169-4332 SN - 1873-5584 VL - 208-209 SP - 333 EP - 339 PB - North-Holland CY - Amsterdam AN - OPUS4-11546 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmitt, R. A1 - Koerfer, F. A1 - Sadowny, O. A1 - Zimmermann, J. A1 - Krüger-Sehm, R. A1 - Xu, M. A1 - Dziomba, T. A1 - Koenders, L. A1 - Goch, G. A1 - Tausendfreund, A. A1 - Patzelt, S. A1 - Simon, S. A1 - Rockstroh, L. A1 - Bellon, Carsten A1 - Staude, Andreas A1 - Woias, P. A1 - Goldschmidtböing, F. A1 - Rabold, M. T1 - Virtuelle Messgeräte - Definition und Stand der Entwicklung JF - Technisches Messen N2 - Die Mikro- und Nanotechnologie gehört zu den Schlüsseltechnologien des 21. Jahrhunderts mit hohen Wachstumsprognosen, wie auch die im Auftrag des BMBF durchgeführte Studie “Nanotechnologie als wirtschaftlicher Wachstumsmarkt” von 2004 ausführlich darstellt. Aus diesem Trend resultiert ein steigender Bedarf an Messsystemen, die Nanostrukturen prozessnah bzw. im Fertigungsprozess charakterisieren können. Virtuelle Messgeräte liefern Erkenntnisse zur Entwicklung neuartiger Messsysteme, Analyse und Optimierung bestehender Verfahren sowie die Bestimmung der Messunsicherheit und modellbasierten Korrektur systematischer Fehler. Der virtuelle Messprozess umfasst neben dem Messmittel auch die Probe und die Wechselwirkungen zwischen beiden. In diesem Beitrag werden virtuelle Messgeräte vorgestellt sowie deren Anwendung diskutiert. N2 - Micro- and nanotechnology experienced a high economic growth in recent years. This yields in a growing demand for measuring instruments which are closely linked to the production process. Virtual measuring instruments provide knowledge for the development of new systems, the analysis and optimization of established devices as well as the determination of the uncertainty in measurement. The virtual measuring process consists of the measuring instrument, the sample, and the interaction between both. In this article examples of current developments of virtual instruments are presented and their way of utilization is discussed. KW - Virtuelle Messtechnik KW - Simulation KW - Messunsicherheit KW - Virtual metrology KW - Measurement uncertainty PY - 2008 DO - https://doi.org/10.1524/teme.2008.0872 SN - 0340-837X SN - 0178-2312 SN - 0171-8096 VL - 75 IS - 5 SP - 298 EP - 310 PB - Oldenbourg CY - München AN - OPUS4-17569 LA - deu 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 - Laser-induced damage in optical materials - 2003 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 - Krüger, Ralph-Peter A1 - Heinemann, M. A1 - Falkenhagen, Jana A1 - Hartmann, A. A1 - Friedrich, Jörg Florian A1 - Fritz, H.-G. ED - Fritz, H. ED - Eisenbach, C. T1 - Charakterisierung biologisch abbaubarer Homo- und Copolyester / Characterisation of biodegradable Homo- and Copolyesters T2 - 19. Stuttgarter Kunststoff-Kolloquium T2 - 19. Stuttgarter Kunststoff-Kolloquium 2005 CY - Stuttgart, Deutschland DA - 2005-03-09 KW - MALDI-TOF-MS KW - Bioabbaubare Polyester KW - Flüssigchromatographie KW - Methodenkopplung KW - Biodegradable polyesters KW - Liquid chromatography KW - Coupling of analytical methods PY - 2005 SN - 3-00-015246-6 SP - 5/P1-1 - 5/P1-9 PB - IKT CY - Stuttgart AN - OPUS4-11767 LA - deu 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 JF - Russian journal of electrochemistry 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 - 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 JF - Applied surface science 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 -