TY - CHAP A1 - Franz, Daniel A1 - Mücke, Dominik A1 - Kunz, Tim A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - UV picosecond laser drilling of ABF film material for printed circuit boards using laser burst mode and beam shaping T2 - International Congress on Applications of Lasers & Electro-Optics (ICALEO) 2023 N2 - We report on an experimental study of laser microvia percussion drilling of Ajinomoto build-up film (ABF) material using an ultrashort pulsed laser in the ultraviolet region. In order to optimize the drilling quality in terms of the fabricated taper and microvia diameter, the MHz burst mode is used in combination with both a Gaussian and a top-hat laser intensity distribution. To evaluate the influence of the top-hat beam shape on defocusing, microvias were drilled at different z-positions in the range of 200 μm evenly distributed around the focal plane. The drilling quality was evaluated by laser scanning microscopy and metallography. When using a top-hat beam shape, a reduced taper of down to 26.8 % on average is achieved compared to a Gaussian beam. For the application of 3 intra-burst pulses, we find an improvement of the taper by 11.6% compared to the single pulse mode due to the increasing heat accumulation. Using a top-hat beam shape in combination with the MHz burst mode, an 18.2 % reduction in laser drilling time for a microvia with a similar taper is remarkable, demonstrating the high potential for scaling throughput in electronics manufacturing. KW - Pikosekundenbereich KW - Laserbohren Y1 - 2023 ER - TY - CHAP A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Axicon fabrication with ultrashort and CO2 laser T2 - LPM2018 The 19th International Symposium on Laser Precision Microfabrication KW - Ultrakurzzeitlaser KW - Kohlendioxidlaser Y1 - 2018 ER - TY - CHAP A1 - Dudutis, Juozas A1 - Pipiras, Jokūbas A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Hellmann, Ralf A1 - Gečys, Paulius T1 - Bessel beam formation with all laser fabricated axicon - case of glass dicing applications T2 - COLA 2019, 15th International Conference on Laser Ablation KW - Laserbestrahlung Y1 - 2019 ER - TY - CHAP A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Current results on laser-based production of complex optics in glass T2 - 10. Wetzlarer Herbsttagung "Moderne Optikfertigung", 29. - 30. September 2020, Wetzlar KW - Laserbearbeitung KW - Fertigungstechnik Y1 - 2020 ER - TY - CHAP A1 - Rung, Stefan A1 - Bischoff, Christian A1 - Jäger, Erwin A1 - Umhofer, Udo A1 - Hellmann, Ralf T1 - Laser thin film ablation with multiple beams and tailored beam profiles T2 - Proceedings of SPIE 8967, Laser Applications in Microelectronic and Optoelectronic Manufacturing (LAMOM) XIX KW - Thin film KW - Ablation KW - Top-Hat KW - Parallel Processing KW - Beam-Splitter KW - Laserablation KW - Dünnschichttechnik Y1 - 2014 VL - 8967 ER - TY - CHAP A1 - Jäger, Erwin A1 - Rädel, Ulrich A1 - Bischoff, Christian A1 - Umhofer, Udo A1 - Rung, Stefan A1 - Hellmann, Ralf T1 - Laser micromachining – parallel processing with multiple top hat beams T2 - 8th International Conference on Photonic Technologies LANE 2014 KW - Laserbearbeitung Y1 - 2014 ER - TY - CHAP A1 - Rung, Stefan A1 - Rexhepi, Mal A1 - Hellmann, Ralf T1 - Beam shaping for enhanced through-put of laser ablation of transparent conductive films T2 - Proceedings of the XXVII MicroCAD International Scientific Conference KW - Laserablation Y1 - 2013 VL - 2013 ER - TY - CHAP A1 - Dudutis, Juozas A1 - Pipiras, Jokūbas A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Hellmann, Ralf A1 - Račiukaitis, Gediminas A1 - Gečys, Paulius T1 - Glass cutting by oblate-tip axicon-generated Bessel-Gaussian beams T2 - Open Readings, 63rd International Conference for Students of Physics and Natural Sciences KW - Laserschneiden KW - Glas Y1 - 2019 ER - TY - CHAP A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Hellmann, Ralf T1 - Simulation of process parameters towards the generation of low spatial frequency LIPSS on dielectric materials T2 - MultiScience - XXX. microCAD International Multidisciplinary Scientific Conference KW - Laserbestrahlung KW - Quarzglas Y1 - 2016 ER - TY - CHAP A1 - Lutz, Christian A1 - Schwarz, Simon A1 - Rung, Stefan A1 - Marx, Jan A1 - Esen, Cemal A1 - Hellmann, Ralf T1 - Optical system for multi Bessel beam high power ultrashort pulsed laser processing using a spatial light modulator T2 - Lasers in Manufacturing - LiM 2021 N2 - We report on an optical setup for multi Bessel beam processing combining a refractive axicon and a spatial light modulator. Based on their particular beam profile, Bessel beams exhibit various advantages over conventional Gaussian beams for ultrashort pulsed laser processing. Especially for micromachining of transparent materials, applications such as micro-hole drilling or the generation of voids benefit from the increased focal length of the applied Bessel beam. In addition, on account of the significantly increased average output power of industrial ultrashort pulsed lasers over the last years, there is a high demand on multi spot applications for using the available laser power in efficient production processes. Our optical concept combines the dynamic possibilities of beam splitting using spatial light modulator with the benefits of Bessel beams facilitating multi Bessel beam processing. KW - Ultrakurzzeitlaser KW - Lichtmodulator Y1 - 2021 ER -