In this study, we worked on the formation of micro through holes in multi-component glass substrates using laser-assisted etching, in which mixed aqueous solutions of hydrofluoric acid (HF) and nitric acid (HNO 3 ) were used for the etching. Glass samples modified by femtosecond laser irradiation were immersed for 10 minutes in aqueous solutions containing 2% HF and between 0 and 32% HNO 3 . The subsequent optical microscope observations and measurements showed that the highest etch selectivity, which was 21, was obtained with an etch solution containing 6% HNO 3 . Furthermore, through holes with diameters approaching 20 μm were successfully formed in a 100 μm thick glass substrate without any cracks using the mixed solution.

Abstract:Laser pulse overlapping is one of the least studied parameters involved in the production of nanoparticles by laser ablation confined in liquids. In order to explore its effect on the yield of nanoparticles, we employed a motorized XY translation stage with speed control, which allowed us to regulate the overlapping of laser pulses on the target. Four different XY speed settings were used in the laser ablation of a silver target in distilled water; each process in a virgin surface, using the 532 nm emission of a Nd:YAG laser, with fixed spot diameter of 1 mm and pulse energy of 0.5 J/pulse. Peak optical absorption, in UV-Visible measurements of each nanoparticle suspension, decreases as the employed pulse overlapping increases. According to the well known Beer-Lambert relation, this implies that nanoparticle yield decreases as the pulse overlapping increases.