Research Projects

IDEAS project
"Study of deterministic nanostructuring methodes"

Near-field optical wave enhancement and multifoton absorbtion of femtosecond laser beam will be used for deterministic nanopatterning. When evanescent optical waves are controlled using nano-optics, such as submicron scattering particles, laser processing of surface with resolution of tens of nanometers can be done. Colloidal spherical particles with size comparable or less than the laser wavelength will be deposit on surface of different materials. Under femtosecond laser beam irradiation of the particles, the evanescent waves are enhanced at the contact point of the spheres with the surface. Thus, small holes are created by evaporation, with diameter of tens to hundreds of nm depending of spheres diameter and laser wavelength. The nanostructures morphology will be studied and the ablation threshold for different thin films will be determined. Despite of their small size, the geometries of the created patterning are limited by the hexagonal surface arrangement of the monolayer of the colloidal particles. In our studies, more complex geometries will be demonstrated by using near-field laser processing on non-spherical masks. Instead of spherical particles, other structures will de used such as lines, grids, or any 2D geometries. These can be produced at nanometer size by femtosecond laser photopolymerization on photoresists using femtosecond laser. The processed surfaces will be characterized by AFM, SEM,  optical spectrospopy and ellispometry. The studied materials will be metallic films such as Au, Ni, Ag, Co, glasses, ceramics, polymers or any other materials with interest for nanotechologies.