On the generation of grooves on crystalline silicon irradiated by femtosecond laser pulses

Abstract

for grooves, respectively. Surface-scattered wave theory, which allows modeling irradiation with a single pulse on a rough surface, is exploited to interpret the observed structural modification of the surface textures. A simple, empirical scaling approach is proposed associating the surface structures generated in multiple-pulse experiments with the predictions of the surface-scattered wave theory, at laser fluencies around the grooves formation threshold. This, in turn, allows proposing a physical mechanism interpreting the grooves generation as well as the coexistence and relative prominence of grooves and ripples in the irradiated area.