Hybrid plasma-laser micro-structuring provides a tool for treating fused silica without the need for a time consuming preconditioning of the surface or the use of expensive vacuum-UV- respectively mid-wavelength-IR-lasers. The use of a hydrogenous plasma prior to the ablation process causes a temporary increase of the absorption in a more easily accessible wavelength region.

Laser ablation is a surface treatment method and is preferably used to remove thin layers or drill narrow holes. As elegant as this technique might be, it demands a sufficient absorption within the treated material or surface. Fused silica however is almost transparent in a range between 200 nm and 2000 nm where laser ablation is usually carried out. As of today there exist two possible solutions to bypass this disadvantage: On the one hand one can add a layer with a higher absorption coefficient onto the transparent surface before ablation but has to make sure that this layer can be completely removed afterwards. On the other hand it is possible to decrease/increase the laser wavelength beyond/above absorption threshold or amplify the energy density of the laser beam. Both solutions increase efforts and thus costs. (Image: Fused silica after conventional laser ablation treatment (left) and after the herein introduced Hybrid Plasma-Laser Micro-Structuring (right). It can clearly be seen, that both contour accuracy and surface roughness are improved by the hybrid technique. )

 How to solve this problem? Read More at MBM ScienceBridge here