TY - JOUR A1 - Krüger, Jörg A1 - Kautek, Wolfgang A1 - Lenzner, M. A1 - Krausz, F. T1 - Precision laser ablation of dielectrics in the 10-fs regime N2 - Zusammenfassung Laser pulses in the 10-fs domain provide a quality of micromachining of fused silica and borosilicate glass that is unobtainable with longer pulses in the range of several 100 femtoseconds up to picoseconds. The shortening of the pulses reduces the statistical behavior of the material removal and the ablation process thus attains a more deterministic and reproducible character. The improved reproducibility of ablation is accompanied by significantly smoother morphology. This offers the potential for lateral and vertical machining precision of the order of 100 nm and 10 nm, respectively. KW - Laser ablation PY - 1999 DO - https://doi.org/10.1007/s003390050906 SN - 0947-8396 VL - 68 IS - 3 SP - 369 EP - 371 PB - Springer CY - Berlin AN - OPUS4-825 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Derrien, Thibault A1 - Koter, Robert A1 - Krüger, Jörg A1 - Höhm, S. A1 - Rosenfeld, A. A1 - Bonse, Jörn T1 - Plasmonic formation mechanism of periodic 100-nm-structures upon femtosecond laser irradiation of silicon in water N2 - The formation of laser-induced periodic surface structures (LIPSS) upon irradiation of silicon by multiple (N = 100) linearly polarized Ti:sapphire femtosecond laser pulses (duration τ = 30 fs, center wavelength λ0 ~ 790 nm) is studied experimentally in air and water environment. The LIPSS surface morphologies are characterized by scanning electron microscopy and their spatial periods are quantified by two-dimensional Fourier analyses. It is demonstrated that the irradiation environment significantly influences the periodicity of the LIPSS. In air, so-called low-spatial frequency LIPSS (LSFL) were found with periods somewhat smaller than the laser wavelength (ΛLSFL ~ 0.7 × λ0) and an orientation perpendicular to the laser polarization. In contrast, for laser processing in water a reduced ablation threshold and LIPSS with approximately five times smaller periods ΛLIPSS ~ 0.15 × λ0 were observed in the same direction as in air. The results are discussed within the frame of recent LIPSS theories and complemented by a thin film based surface plasmon polariton model, which successfully describes the tremendously reduced LIPSS periods in water. PY - 2014 DO - https://doi.org/10.1063/1.4887808 SN - 0021-8979 SN - 1089-7550 VL - 116 IS - 7 SP - 074902-1 EP - 074902-8 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-31209 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Voss, Heike A1 - Knigge, Xenia A1 - Knapic, D. A1 - Weise, Matthias A1 - Sahre, Mario A1 - Hertwig, Andreas A1 - Sacco, A. A1 - Rossi, A. M. A1 - Radnik, Jörg A1 - Müller, Kai A1 - Wasmuth, Karsten A1 - Krüger, Jörg A1 - Hassel, A. W. A1 - Hodoroaba, Vasile-Dan A1 - Bonse, Jörn T1 - Picosecond laser processing of hierarchical micro–nanostructures on titanium alloy upon pre- and postanodization: morphological, structural, and chemical effects N2 - Recent publications indicate that the order of electrochemical anodization (before or after the laser processing step) plays an important role for the response of bone-forming osteoblasts—an effect that can be utilized for improving permanent dental or removable bone implants. For exploring these different surface functionalities, multimethod morphological, structural, and chemical characterizations are performed in combination with electrochemical pre- and postanodization for two different characteristic microspikes covered by nanometric laser-induced periodic surface structures on Ti–6Al–4V upon irradiation with near-infrared ps-laser pulses (1030 nm wavelength, ≈1 ps pulse duration, 67 and 80 kHz pulse repetition frequency) at two distinct sets of laser fluence and beam scanning parameters. This work involves morphological and topographical investigations by scanning electron microscopy and white light interference microscopy, structural material examinations via X-ray diffraction, and micro-Raman spectroscopy, as well as near-surface chemical analyses by X-ray photoelectron spectroscopy and hard X-ray photoelectron spectroscopy. The results allow to qualify the mean laser ablation depth, assess the spike geometry and surface roughness parameters, and provide new detailed insights into the near-surface oxidation that may affect the different cell growth behavior for pre- or postanodized medical implants. T2 - 2023 E-MRS Spring Meeting, Symposium L "Making light matter: lasers in material sciences and photonics" CY - Strasbourg, France DA - 29.05.2023 KW - Hierarchical micro-nanostructures KW - Laser-induced periodic surface structures (LIPSS) KW - Ultrashort laser pulses KW - Ti-6Al-4V alloy KW - X-ray photoelectron spectroscopy PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-601962 DO - https://doi.org/10.1002/pssa.202300920 SN - 1862-6319 SP - 1 EP - 11 PB - Wiley-VCH GmbH CY - Weinheim AN - OPUS4-60196 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 - 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 - JOUR A1 - Krüger, Jörg A1 - Kautek, Wolfgang A1 - Lenzner, M. A1 - Krausz, F. T1 - Photoablation with sub-10 fs laser pulses N2 - Ablation experiments in several glasses with single and multishot irradiation by laser pulses in the 10-fs pulse duration domain are presented; physical and technological implications are discussed. We demonstrate that these short pulses offer the potential for lateral and vertical machining precision of the order of 100 nm. KW - Ablation KW - Laser pulses KW - Femtosecond pulses PY - 2000 DO - https://doi.org/10.1016/S0169-4332(99)00432-8 SN - 0169-4332 SN - 1873-5584 VL - 154-155 SP - 11 EP - 16 PB - North-Holland CY - Amsterdam AN - OPUS4-800 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kautek, Wolfgang A1 - Sorg, N. A1 - Krüger, Jörg ED - Brieger, M. T1 - Optical second-harmonic generation (SHG) on semiconductor electrodes by means of femtosecond and nanosecond-pulse lasers N2 - In situ optical second-harmonic generation (SHG) on centrosymmetric crystalline semiconductor electrodes opens up a new field of in situ investigations of hurried solid state interfaces and metal front contacts relevant to electronic and photovoltaic devices, which are rarely accessible by other methods. Photoelectrochemical nanosecond- and femtosecond-pulse laser investigations of silicon (111) electrodes show that in situ SHG is feasible in such complex interfacial systems. In a p-p polarization configuration, the azimuthal dependence of the SHG from oxide-covered and bare n-Si (111) electrodes, with and without Ni contact deposits, have been studied. Etching and regrowth of silicon oxides as well as burried interfacial electric field distributions were monitored. In situ SHG is shown to be extremely sensitive to trapped interfacial charge, crystal misorientations and surface step arrays. An advantage of femtosecond-pulses is the fact that illumination fluences that are well below the damage threshold, but still with sufficient power density, can be applied. (Author) T2 - 1st International Symposium on Semiconductor Processing and Characterization with Lasers - Applications in Photovoltaics CY - Stuttgart, Germany DA - 1994-04-18 KW - Femtosecond-Pulse Laser KW - Sub-Picosecond-Pulse Laser KW - Semiconductors KW - Silicon KW - Second-Harmonic Generation KW - SHG KW - Nonlinear Electroreflectance KW - Etch Process KW - Oxide KW - Interfacial Electronic States KW - Fermi-Level Pinning KW - MOS Diode PY - 1995 SN - 0-87849-683-1 DO - https://doi.org/10.4028/www.scientific.net/MSF.173-174.285 SN - 0255-5476 N1 - Serientitel: Materials science forum – Series title: Materials science forum IS - 173/174 SP - 285 EP - 290 PB - Trans Tech Publ. CY - Aedermannsdorf AN - OPUS4-11672 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 - JOUR A1 - Bonse, Jörn A1 - Rosenfeld, A. A1 - Krüger, Jörg T1 - On the role of surface plasmon polaritons in the formation of laser-induced periodic surface structures upon irradiation of silicon by femtosecond-laser pulses N2 - The formation of nearly wavelength-sized laser-induced periodic surface structures (LIPSSs) on single-crystalline silicon upon irradiation with single or multiple femtosecond-laser pulses (pulse duration τ=130 fs and central wavelength λ=800 nm) in air is studied experimentally and theoretically. In our theoretical approach, we model the LIPSS formation by combining the generally accepted first-principles theory of Sipe and co-workers with a Drude model in order to account for transient intrapulse changes in the optical properties of the material due to the excitation of a dense electron-hole plasma. Our results are capable to explain quantitatively the spatial periods of the LIPSSs being somewhat smaller than the laser wavelength, their orientation perpendicular to the laser beam polarization, and their characteristic fluence dependence. Moreover, evidence is presented that surface plasmon polaritons play a dominant role during the initial stage of near-wavelength-sized periodic surface structures in femtosecond-laser irradiated silicon, and it is demonstrated that these LIPSSs can be formed in silicon upon irradiation by single femtosecond-laser pulses. KW - Ab initio calculations KW - Elemental semiconductors KW - High-speed optical techniques KW - Laser beam effects KW - Polaritons KW - Silicon KW - Solid-state plasma KW - Surface plasmons KW - Surface structure PY - 2009 DO - https://doi.org/10.1063/1.3261734 SN - 0021-8979 SN - 1089-7550 VL - 106 IS - 10 SP - 104910-1 - 104910-5 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-20453 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 - 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 - 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 - CONF A1 - Krüger, Jörg A1 - Mann, Guido A1 - Vogel, Jens A1 - Preuß, Rüdiger A1 - Vaziri, Pouya A1 - Eberstein, Markus A1 - Zoheidi, M. T1 - Nanosecond laser-induced surface damage of preforms and optical multimode fibers T2 - COLA 2007, Conference on Laser Ablation, Guia de Isora CY - Tenerife, Spain DA - 2007-09-24 PY - 2007 AN - OPUS4-14956 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mann, Guido A1 - Vogel, Jens A1 - Preuß, Rüdiger A1 - Vaziri, Pouya A1 - Zoheidi, M. A1 - Eberstein, Markus A1 - Krüger, Jörg T1 - Nanosecond laser-induced surface damage of optical multimode fibers and their preforms N2 - High-power optical multimode fibers are essential components for materials processing and surgery and can limit the performance of expensive systems due to breakdown at the end faces. The aim of this paper is the determination of laser-induced damage thresholds (LIDT) of fibers (FiberTech) and preforms (Heraeus Suprasil F300). Preforms served as models. They were heated up to maximum temperatures of 1100, 1300 and 1500°C and cooled down to room temperature at rates of 10 K min-1 (oven) and ~105 K min-1 (quenched in air) to freeze in various structural states simulating different conditions similar to a drawing process during the production of fibers. Single- and multi-pulse LIDT measurements were done in accordance with the relevant ISO standards. Nd:YAG laser pulses with durations of 15 ns (1064 nm wavelength) and 8.5 ns (532 nm) at a repetition rate of 10 Hz were used. For the preforms, LIDT values (1-on-1) ranged from 220 to 350 J/cm² (1064 nm) and from 80 to 110 J/cm² (532 nm), respectively. A multi-pulse impact changed the thresholds to lower values. The LIDT (1064 nm wavelength) of the preforms can be regarded as a lower limit for those of the fibers. PY - 2008 DO - https://doi.org/10.1007/s00339-008-4576-1 SN - 0947-8396 VL - 92 IS - 4 SP - 853 EP - 857 PB - Springer CY - Berlin AN - OPUS4-17779 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, Jörg A1 - Mann, Guido A1 - Vogel, Jens A1 - Preuß, Rüdiger A1 - Vaziri, Pouya A1 - Eberstein, Markus A1 - Zoheidi, M. T1 - Nanosecond laser damage resistance of optical multimode fibers prepared differently T2 - EMRS 2007 Spring Meeting, Symposium P: Laser synthesis and processing of advanced materials CY - Strasbourg, France DA - 2007-05-28 PY - 2007 AN - OPUS4-14762 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mann, Guido A1 - Vogel, Jens A1 - Preuß, Rüdiger A1 - Vaziri, Pouya A1 - Zoheidi, M. A1 - Eberstein, Markus A1 - Krüger, Jörg T1 - Nanosecond laser damage resistance of differently prepared semi-finished parts of optical multimode fibers N2 - Optical multimode fibers are applied in materials processing (e.g. automotive industry), defense, aviation technology, medicine and biotechnology. One challenging task concerning the production of multimode fibers is the enhancement of laser-induced damage thresholds. A higher damage threshold enables a higher transmitted average power at a given fiber diameter or the same power inside a thinner fiber to obtain smaller focus spots. In principle, different material parameters affect the damage threshold. Besides the quality of the preform bulk material itself, the drawing process during the production of the fiber and the preparation of the fiber end surfaces influence the resistance. Therefore, the change of the laser-induced damage threshold of preform materials was investigated in dependence on a varying thermal treatment and preparation procedure. Single and multi-pulse laser-induced damage thresholds of preforms (F300, Heraeus) were measured using a Q-switched Nd:YAG laser at 1064 nm wavelength emitting pulses with a duration of 15 ns, a pulse energy of 12 mJ and a repetition rate of 10 Hz. The temporal and spatial shape of the laser pulses were controlled accurately. Laser-induced damage thresholds in a range from 150 J cm-2 to 350 J cm-2 were determined depending on the number of pulses applied to the same spot, the thermal history and the polishing quality of the samples, respectively. KW - Laser ablation KW - Optical fibers KW - Physical radiation damage KW - Radiation treatment KW - Glass transitions KW - Glasses PY - 2007 DO - https://doi.org/10.1016/j.apsusc.2007.09.032 SN - 0169-4332 SN - 1873-5584 VL - 254 IS - 4 SP - 1096 EP - 1100 PB - North-Holland CY - Amsterdam AN - OPUS4-16207 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mann, Guido A1 - Krüger, Jörg ED - Jitsuno, T. ED - Shao, J. ED - Rudolph, W. T1 - Nanosecond laser damage of optical multimode fibers N2 - For pulse laser materials processing often optical step index and gradient index multimode fibers with core diameters ranging from 100 to 600 μm are used. The design of a high power fiber transmission system must take into account limitations resulting from both surface and volume damage effects. Especially, breakdown at the fiber end faces and self-focusing in the fiber volume critically influence the fiber performance. At least operation charts are desirable to select the appropriate fiber type for given laser parameters. In industry-relevant studies the influence of fiber core diameter and end face preparation on laser-induced (surface) damage thresholds (LIDT) was investigated for frequently used all-silica fiber types (manufacturer LEONI). Experiments on preform material (initial fiber material) and compact specimens (models of the cladding and coating material) accompanied the tests performed in accordance with the relevant LIDT standards ISO 21254-1 and ISO 21254 2 for 1-on-1 and S-on-1 irradiation conditions, respectively. The relation beam diameter vs. LIDT was investigated for fused silica fibers. Additionally, laser-induced (bulk) damage thresholds of fused silica preform material F300 (manufacturer Heraeus) in dependence on external mechanical stress simulating fiber bending were measured. All experiments were performed with 10-ns laser pulses at 1064 and 532 nm wavelength with a Gaussian beam profile. T2 - Pacific Rim Laser Damage 2016 CY - Yokohama, Japan DA - 18.05.2016 KW - laser damage KW - optical fiber KW - nanosecond laser KW - fused silica PY - 2016 DO - https://doi.org/10.1117/12.2238515 VL - 9983 SP - 99830T AN - OPUS4-37140 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, Jörg A1 - Mann, Guido T1 - Nanosecond laser damage of optical multimode fibers N2 - For pulse laser materials processing often optical step index and gradient index multimode fibers with core diameters ranging from 100 to 600 μm are used. The design of a high power fiber transmission system must take into account limitations resulting from both surface and volume damage effects. Especially, breakdown at the fiber end faces and self-focusing in the fiber volume critically influence the fiber performance. At least operation charts are desirable to select the appropriate fiber type for given laser parameters. In industry-relevant studies the influence of fiber core diameter and end face preparation on laser-induced (surface) damage thresholds (LIDT) was investigated for frequently used all-silica fiber types (manufacturer LEONI). Experiments on preform material (initial fiber material) and compact specimens (models of the cladding and coating material) accompanied the tests performed in accordance with the relevant LIDT standards ISO 11254-1 and ISO 11254-2 for 1-on-1 and S-on-1 illumination conditions, respectively. The relation beam diameter vs. LIDT was investigated for fused silica fibers and preforms. Additionally, the laser-induced (bulk) damage threshold of fused silica preform material F300 (manufacturer Heraeus) in dependence on external mechanical stress simulating fiber bending was measured. All experiments were performed with 10-ns laser pulses at 1064 and 532 nm wavelength with a Gaussian beam profile. T2 - Pacific Rim Laser Damage Conference CY - Yokohama, Japan DA - 18.05.2016 KW - Laser induced damage KW - Optical multimode fiber KW - Nd:YAG laser KW - Nanosecond Pulses PY - 2016 AN - OPUS4-36258 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kirner, Sabrina A1 - Wirth, Thomas A1 - Sturm, Heinz A1 - Krüger, Jörg A1 - Bonse, Jörn T1 - Nanometer-resolved chemical analyses of femtosecond laser-induced periodic surface structures on titanium N2 - The chemical characteristics of two different types of laser-induced periodic surface structures (LIPSS), so-called high and low spatial frequency LIPSS (HSFL and LSFL), formed upon irradiation of titanium surfaces by multiple femtosecond laser pulses in air (30 fs, 790 nm, 1 kHz), are analyzed by various optical and electron beam based surface analytical techniques, including micro-Raman spectroscopy, energy dispersive X-ray analysis, X-ray photoelectron spectroscopy, and Auger electron spectroscopy. The latter method was employed in a high-resolution mode being capable of spatially resolving even the smallest HSFL structures featuring spatial periods below 100 nm. In combination with an ion sputtering technique, depths-resolved chemical information of superficial oxidation processes was obtained, revealing characteristic differences between the two different types of LIPSS. Our results indicate that a few tens of nanometer shallow HSFL are formed on top of a ∼150 nm thick graded superficial oxide layer without sharp interfaces, consisting of amorphous TiO2 and partially crystallized Ti2O3. The larger LSFL structures with periods close to the irradiation wavelength originate from the laser-interaction with metallic titanium. They are covered by a ∼200 nm thick amorphous oxide layer, which consists mainly of TiO2 (at the surface) and other titanium oxide species of lower oxidation states underneath. KW - Laser-induced periodic surface structures (LIPSS) KW - Femtosecond laser KW - Oxidation KW - Titanium KW - Auger electron spectroscopy PY - 2017 DO - https://doi.org/10.1063/1.4993128 SN - 0021-8979 VL - 122 IS - 10 SP - 104901, 1 EP - 9 PB - AIP Publishing CY - Melville, NY, USA AN - OPUS4-41905 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 -