Submicron periodic structures produced on polymer surfaces with polarized excimer laser ultraviolet radiation

For the first time, pure laser induced periodic structures (without any ablation or any larger structure) of submicron size (spacing and amplitude of 0.2 μm) are developed on polymer surfaces [poly(ethylene terephthalate), poly(butylene terephthalate) and polystyrene] by irradiation with one thousand pulses of the polarized beam of the excimer laser (193 and 248 nm). Fluence is below the ablation threshold and must be chosen in a narrow window which depends on the polymer and the wavelength. The obtained relief is observed by SEM, TEM and characterized by ellipsometry. Structures are obtained also by irradiation of thin films (2000 A) coated on silicon wafers.