Micropatterning of Foturan photosensitive glass following exposure to MeV proton beams

A new proton lithography mechanism has been identified and investigated: the micropatterning of photosensitive etchable glass based on the crystallization of the glass after irradiation with MeV protons and heat treatment. The use of MeV protons results in a significantly reduced minimum feature size compared with reported results using ultraviolet (UV) irradiation and the threshold dose for etching is very low (4000 protons µm−2), offering the potential for creating complex microstructures by direct writing using very short exposures. The depth of the structures is determined only by the range of the protons in the glass, which allows structures with different depths to be fabricated. This technique appears to be very valuable for the rapid fabrication of high aspect ratio microstructures such as fluid networks and micro-optical devices in a material with useful optical and mechanical properties.