Microstructuring of glass with excimer laser radiation at different processing gas atmospheres for microreaction technology

Microstructuring of soda lime glass with excimer laser radiation is examined to present its process capabilities for production of surface structures particularly for microreaction technology. Material removal rates, geometries of microstructures and transmission/reflexion of processed soda lime glass are investigated for ArF excimer laser radiation (lambda(L)= 193 nm, tau(L)= 20 ns) and KrF excimer laser radiation (lambda(L)= 248 nm, tau(L)= 25 ns). Processing of glass at atmospheric pressure down to vacuum at p= 10 mbar (He as processing gas) is carried out to investigate the correlation between processing gas pressure and generation of debris (solidification of molten material and re-deposition from expanding vapor/plasma). The influence of processing gas atmospheres consisting of He/F-2 (50/50 vol.%) with a total pressure in the vacuum chamber of 10 mbar < p< 250 mbar on height/ width of the debris is examined. Ultrasonic cleaning of glass after processing is investigated for reduction of debris. Optical microscopy, white light interferometry, optical spectroscopy and X-ray photoelectron spectroscopy (XPS) are used for analysis of microstructures and debris.