Abstract
Direct femtosecond laser nanopatterning of glass substrate by particle-assisted near-field enhancement was demonstrated in this letter. The nanostructure was characterized by field-emission scanning electron microscopy and atomic force microscopy. No cracks were found on the glass surface. The hole size were measured from
200
∼
300
nm
. When laser fluence is close to the damage threshold, a trihole structure was observed. Nonlinear multiphoton absorption and near-field enhancement were the mechanisms of the nanofeature formation. Calculations based on particle-on-surface theory were carried out. The suggested method has potential applications in the nanolithography of a transparent glass substrate for nanostructure device fabrication.