UV-laser fabrication of sub-micron hole arrays in glass by phase mask projection

Parallel processing of sub-µm holes in a glass surface using ArF excimer laser ablation at a wavelength of 193 nm is demonstrated. To utilize the laser energy most efficiently, a fused silica phase mask is applied, which is projected on the glass surface with a Schwarzschild type reflective objective. Hole arrays with 500 nm pitch and individual holes with 250 nm diameter and more than 100 nm depth are obtained. Holes in soda lime glass are made by direct laser ablation; fused silica is processed by depositing a SiOx-film on SiO2, patterning the SiOx by ablation, and finally oxidizing the remaining SiOx to SiO2. Glass slides patterned in this way can be used as templates for the ordered arrangement of gold nanoparticles by thermally induced dewetting of deposited thin films.