Stuttgart 2012 – wissenschaftliches Programm
Q 42.6: Vortrag
Donnerstag, 15. März 2012, 11:45–12:00, V38.04
. Laser-induced front side etching (LIFE) of crystalline silica — •Pierre Lorenz1, Daniel Spemann2, Martin Ehrhardt1, and Klaus Zimmer1 — 1Leibniz-Institute of Surface Modification, Permoserstr. 15, 04318 Leipzig, Germany — 2Nuclear Solid State Physics, University of Leipzig, Linnestr. 5, 04103 Leipzig, Germany
Laser-induced front side etching (LIFE) is a method for laser etching of dielectrics using thin metallic absorber layers. However, the mechanism of the LIFE method is poorly understood. For the better understanding of the underlying process, some basic investigations were performed and the results were compared to theoretical consideration. Within this study the etching of crystalline silica with thin chromium layers as absorbers is presented using nanosecond KrF excimer laser radiation (λ = 248 nm, 25 ns pulses, 100 Hz). The laser fluence as well as the number of pulses was varied. The processed silica surfaces were analysed by different microscopic (scanning electron microscopy (SEM), white light interferometry (WLI)) and spectroscopic methods (photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDX), Rutherford backscattering spectrometry (RBS)). Furthermore, the optical properties of the laser irradiation modified fused silica near-surface region were investigated by depth-dependence transmission measurements. Alternately, the modified material was thinned by ion beam sputtering and transmission measurements were performed. A thermal model calculated by finite element method (FEM) is presented for the discussion of the results.