The efficiency and quality of silicon micromachining above the ablation threshold: a comparison for femto, pico and nanosecond laser

Abstract

In the paper the results of 3D micromachining of silicon using nanosecond (1064 nm), picosecond (343 nm) and femtosecond (343 nm) laser pulses are presented. Effective laser processing demands repeated scanning of the laser beam and overlapping of paths what generate many phenomena which do not occur by impact of individual laser pulses. Thermal incubation effect and shielding of laser beam by ejected particles compete and decide on the final result of ablative micromachining. Applying femto and picosecond laser pulses does not directly guarantee expected quality and effectiveness.