Analysis of the formation and evolution of oriented microstructures on laser ablated silicon

A theoretical approach and qualitative analysis of the changes induced on the surface morphology and the formation of microstructures on silicon targets irradiated by excimer laser are presented. This study is based on theoretical principles of the laser ablation process, in particular, on the analysis of the contribution of the laser energy density, which involves the laser beam parameters and also the physical properties of the target material. For different laser incident angles, the formation of micro-columns oriented towards the laser incident direction is explained. Moreover, numerical simulations and ablation experiments carried out with an excimer laser corroborate the theoretical analysis.