Fabrication of hierarchical structures by direct laser writing and multi-beam-interference

We present a new method for the creation of hierarchical structures by two subsequent steps of laser ablation. To create certain functionalization of surfaces hierarchical structures are often required. These structures can be considered as a microstructure with a superposed nanostructure. Therefore the approach presented in this paper divides the patterning process into two parts: The microstructures are accomplished by direct laser writing with feature sizes down to a few microns whereas the nanostructure is subsequently added by Multi-beam-interference (MBI). Multi-beaminterference is a promising tool for the generation of nanostructures on 3D surfaces. Within this work the feasibility and limitations of this method are investigated.