Laser-assisted nanopatterning of aluminium using particle-induced near-field optical enhancement and nanoimprinting

摘要

Laser-assisted nanopatterning of aluminium (Al) thin films using particle-induced near-field optical enhancement and nanoimprinting has been investigated experimentally and theoretically. It is found that nano pit arrays can be created on Al surfaces by laser irradiation (KrF excimer laser, lambda = 248 nm) on an Al surface on which a monolayer of silica particles has been self-assembled. The influence of particle size and laser fluence on the structuring of Al surfaces has been examined. Particles with various diameters of 0.97, 2.34 and 5.06 mu m were used in the experiment. Near-field optical enhancement and nanoimprinting were identified to explain the mechanisms for the formation of different structures on Al surfaces under different laser fluences. A high frequency structure simulator (HFSS) was used to simulate the optical field distribution in the particles attached on Al surfaces.