{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T07:45:01Z","timestamp":1782373501273,"version":"3.54.5"},"reference-count":11,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2014,10,27]],"date-time":"2014-10-27T00:00:00Z","timestamp":1414368000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>Thin film ablation with pulsed nanosecond lasers can benefit from the use of beam shaping optics to transform the Gaussian beam profile with a circular footprint into a Top-Hat beam profile with a rectangular footprint. In general, the quality of the transformed beam profile depends strongly on the beam alignment of the entire laser system. In particular, the adjustment of the beam shaping element is of upmost importance. For an appropriate alignment of the beam shaper, it is generally necessary to observe the intensity distribution near the focal position of the applied focusing optics. Systems with a low numerical aperture (NA) can commonly be qualified by means of laser beam profilers, such as a charge-coupled device (CCD) camera. However, laser systems for micromachining typically employ focus lenses with a high NA, which generate focal spot sizes of only several microns in diameter. This turns out to be a challenge for common beam profiling measurement systems and complicates the adjustment of the beam shaper strongly. In this contribution, we evaluate the quality of a Top-Hat beam profiling element and its alignment in the working area based on the ablated geometry of single pulse ablation of thin transparent conductive oxides. To determine the best achievable adjustment, we develop a quality index for rectangular laser ablation spots and investigate the influences of different alignment parameters, which can affect the intensity distribution of a Top-Hat laser beam profile.<\/jats:p>","DOI":"10.3390\/mi5040943","type":"journal-article","created":{"date-parts":[[2014,10,27]],"date-time":"2014-10-27T11:38:09Z","timestamp":1414409889000},"page":"943-953","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":42,"title":["Characterization of Laser Beam Shaping Optics Based on Their Ablation Geometry of Thin Films"],"prefix":"10.3390","volume":"5","author":[{"given":"Stefan","family":"Rung","sequence":"first","affiliation":[{"name":"University of Applied Science Aschaffenburg, Wuerzburger Strasse 45, D-63743 Aschaffenburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Johannes","family":"Barth","sequence":"additional","affiliation":[{"name":"University of Applied Science Aschaffenburg, Wuerzburger Strasse 45, D-63743 Aschaffenburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ralf","family":"Hellmann","sequence":"additional","affiliation":[{"name":"University of Applied Science Aschaffenburg, Wuerzburger Strasse 45, D-63743 Aschaffenburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2014,10,27]]},"reference":[{"key":"ref_1","unstructured":"Baird, B., Gerke, T., Wieland, K., and Paudel, N. (2011, January 5\u20138). P2 and P3 Spatially Shaped Laser Scribing of CdTe and a-Si Thin Film Solar Cells Using a 532 nm Picosecond MOFPA. Proceedings of 26th European Photovoltaic Solar Energy Conference and Exhibition, Hamburg, Germany."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"37","DOI":"10.2961\/jlmn.2011.01.0009","article-title":"Laser processing by using diffractive optical laser beam shaping technique","volume":"6","author":"Raciukaitis","year":"2011","journal-title":"J. Laser Micro\/Nanoeng."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Steiger, E., Scharnagl, M., Kemnitzer, M., and Laskin, A. (2009, January 2\u20135). Optimization of the Structuring Processes of CI(G)S Thin-Film Solar Cells with an Ultrafast Picosecond Laser and a Special Beam Shaping Optics. Proceedings of 28th International Congress on Applications of Lasers & Electro-Optics (ICALEO), Orlando, FL, USA.","DOI":"10.2351\/1.5061488"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"309","DOI":"10.2961\/jlmn.2013.03.0021","article-title":"Laserscribing of thin films using Top-Hat laser beam profiles","volume":"8","author":"Rung","year":"2013","journal-title":"J. Laser Micro\/Nanoeng."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Hauschild, D., Homburg, O., Mitra, T., Ivanenko, M., Jarczynski, M., Meinschien, J., Bayer, A., and Lissotschenko, V. (2009, January 28\u201329). Optimizing Laser Beam Profiles Using Micro-Lens Arrays for Efficient Material Processing: Applications to Solar Cells. Proceedings of SPIE 7202 Laser-Based Micro- and Nanopackaging and Assembly III, San Jose, CA, USA.","DOI":"10.1117\/12.809270"},{"key":"ref_6","unstructured":"Bovatsek, J., and Patel, R.S. (November, January 29). 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Proceedings of 34th IEEE Photovoltaic Specialists Conference (PVSC), Philadelphia, PA, USA.","DOI":"10.1109\/PVSC.2009.5411310"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"861741","DOI":"10.1155\/2014\/861741","article-title":"Development of amorphous\/microcrystalline silicon tandem thin-film solar modules with low output voltage, high energy yield, low light-induced degradation, and high damp-heat reliability","volume":"2014","author":"Tsai","year":"2014","journal-title":"J. Nanomater."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"196","DOI":"10.1364\/OL.7.000196","article-title":"Simple technique for measurements of pulsed Gaussian-beam spot sizes","volume":"7","author":"Liu","year":"1982","journal-title":"Opt. Lett."},{"key":"ref_11","unstructured":"TOPAG. Available online:http:\/\/www.topag.de."}],"container-title":["Micromachines"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-666X\/5\/4\/943\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:17:29Z","timestamp":1760217449000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-666X\/5\/4\/943"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2014,10,27]]},"references-count":11,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2014,12]]}},"alternative-id":["mi5040943"],"URL":"https:\/\/doi.org\/10.3390\/mi5040943","relation":{},"ISSN":["2072-666X"],"issn-type":[{"value":"2072-666X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2014,10,27]]}}}