Polymer Nanostructuring by Two-Photon Absorption

Two-photon polymerization (2PP) is an innovative technology that in recent years showed a tremendous potential for three-dimensional structuring of photopolymers at the submicron scale. It is based on the nonlinear absorption of ultrashort laser pulses in transparent photosensitive materials. 2PP has been so far exploited in various fields, including photonics, microfluidics, regenerativemedicine and MEMS prototyping. The versatility of this technology relies also on the photomaterials; indeed, polymers are easy to process, low cost and they allow the tailoring of their chemical and mechanical properties. 2PP nanotechnology is here exploited to produce micro and nanostructures that can be easily customized both in the geometry and in polymer functionalization. In particular, atomic force microscopy tips are fabricated on top of commercial cantilevers to demonstrate the technology feasibility and customizability. Moreover nanoporous membranes that can be fabricated by 2PP as a single custom product or as a mould for mass production through replica moulding are realized to evaluate the scalability of the fabrication process.