Nano-patterning by pulsed laser irradiation in near field

Pulsed laser irradiation in near field is one of effective ways to break optical diffraction limit for surface nano-structuring. Femtosecond laser (400 nm, 100 fs) irradiation through near-field scanning optical microscopy for sub-50 nm resolution is studied. Application of transparent particles' mask by the self-assembly for nano-hole array fabrication is also investigated. It is attributed to light enhancement in near field through the particles.