Laser polishing using ultrashort pulse laser

As a result of laser ablation, a surface roughness S_a between 0.4 μm and 2μm is obtained on 3D structures that have to be polished afterwards to meet customer requirements. For that reason a laser polishing process using ultrashort pulse laser sources is investigated. Applying the polishing process immediately after laser structuring in the same setting simplifies the process chain and saves both time and money. The results reveal an improvement of the surface roughness from an initial grinded surface with 0.4 μm to 0.2 μm by ultrashort pulse laser polishing. The productivity measured by the area that can be processed per time (polishing rate) is with 12.15 cm²/min one order of magnitude higher than state of the art laser polishing using nanosecond pulsed lasers.