Front-surface fabrication of moderate aspect ratio micro-channels in fused silica by single picosecond Gaussian-Bessel laser pulse

摘要

Single-shot Gaussian-Bessel laser beams of 1 ps pulse duration and of similar to 0.9 mu m core size and similar to 60 mu m depth of focus are used for drilling micro-channels on front side of fused silica in ambient condition. Channels ablated at different pulse energies are fully characterized by AFM and post-processing polishing procedures. We identify experimental energy conditions (typically 1.5 mu J) suitable to fabricate non-tapered channels with mean diameter of similar to 1.2 mu m and length of similar to 40 mu m while maintaining an utmost quality of the front opening of the channels. In addition, by further applying accurate post-polishing procedure, channels with high surface quality and moderate aspect ratio down to a few units are accessible, which would find interest in the surface micro-structuring of materials, with perspective of further scalability to meta-material specifications.