Surface morphology and structure modification of silicon layers induced by nanosecond laser radiation

New kinds of surface structures were observed during nanosecond pulsed-laser recrystallization of silicon layers. We observed, depending on the crystalline structure of the surface (amorphous or polycrystalline), after the local melting of the surface the formation of dome-shaped regions, and a dendritic surface structure at epitaxial recrystallization of the silicon layer. Also after the etching, we revealed circular surface structures on the boundary of the transition from fine-grained to large-grained recrystallized structures connected with the diffraction on the generated optical surface heterogeneities.