Realization of ~10 nm features on semiconductor surfaces via femtosecond laser direct patterning in far field and in ambient air.

Direct fabrication of ~10 nm features by optical means in far field and in ambient air on semiconductor surfaces is significant for next-generation advance nanomanufacturing. We report here a new method that enables the direct formation of 12 nm (λ/66) features on silicon surfaces. It is processed in far field and in ambient air via the irradiation of orthogonally polarized double femtosecond laser beams. The coupling of orthogonally polarized double femtosecond laser beams, and the incubation effect due to multiple femtosecond laser pulses irradiation under high repetition rate enable the 12 nm nanostructures creation parallel to scanning direction, regardless of scanning path.