Nanostructuring of fused silica surfaces induced by KrF excimer laser radiation: Experiment and theory

摘要

Nanostructures as well as nanoparticles have a large field of application and a growing economic importance. The usage of laser methods exhibits an outstanding potential for a fast, flexible, and cost-effective production of nanostructures. In particular, the IPSM-LIFE method (IPSM-LIFE: laser-induced front side etching using in situ pre-structured metal layers) allows the easy production of nanostructures in dielectric surfaces. In IPSM-LIFE metal layer-covered dielectric substrates are irradiated with low laser fluences. This results in the formation of complex metal structures through self-assembling processes. An additional high-energy laser irradiation of the metal-structures-covered silica causes the guided formation of complex nanopatterns in the dielectric surface. The chromium-covered fused silica samples were irradiated by a KrF excimer laser and the structured surface was studied by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The experimental results of IPSM-LIFE are discussed with a theoretical approach considering the laser-solid interaction, the heat equation and the restructuring of the liquid film by a Navier-Stokes equation.