Upscaling potential and industrial-suitability of scanner-based Direct Laser Interference Patterning

摘要

Functional surface structures in the range of nano- and micrometers can be used on various technological products to improve mechanical, biological or optical properties. Further important criteria for industrial end-user applications are the process speeds that are required to produce func-tional surface structures. In this study, the fabrication of periodic microstructures on stainless steel using a galvanometer-scanner-based direct laser interference patterning (DLIP) approach is ad-dressed. With the used DLIP setup different scan fields were generated and are evaluated with re-spect to the maximum scan field size in dependence on the spatial period. Furthermore, the correla-tion between spatial period, laser fluence, total number of pulses and the resulting structure depth of the line-like patterns is investigated and discussed. The study shows that the optimization of process parameter can lead to surface patterns with aspect ratios greater than one, which are important for various industrial applications. The combination of the scanner-based DLIP approach with low power ultra-short laser sources (<15 W) results in process throughputs of 250 cm²/min. The effec-tiveness of the approach is exemplified by means of decorative surfaces (varying diffractive colors) and holographic elements.