Effects of picosecond pulsed laser radiation on crater formation on copper foil surfaces

Abstract This study investigates crater formation on copper foil surfaces under picosecond-pulsed Nd:YAG laser irradiation at 1064nm. Spectroscopic analysis examines plasma parameters, including electron density ( N e ), electron temperature ( T e ), plasma frequency, and absorption properties. The results indicate that the laser energy density significantly influences crater formation dynamics and plasma characteristics, affecting material removal mechanisms. In contrast to previous assumptions, spectral analysis confirms that the dominant spectral lines in the plasma correspond to neutral Cu atoms (Cu I) rather than singly ionized Cu(I) ions. This correction ensures an accurate interpretation of laser-induced plasma properties. The findings contribute to a deeper understanding of laser-matter interactions, which is crucial for controlled micro and nanostructuring, material processing, and laser machining applications. Finally, the correlation between laser energy density and crater diameter on copper foil surfaces under picosecond pulsed laser irradiation is investigated, and it is found that higher energy densities yield larger crater diameters. This relationship provides essential insights into the ablation mechanism, potentially advancing the optimization of laser microstructuring and material processing techniques.