The Nonlinear Lithography Group specializes in the fabrication and characterization of micro/nanostructures using two-photon polymerization. Direct laser writing by two-photon polymerization (2PP) of photosensitive materials, has emerged as a promising technique for rapid and flexible fabrication of fully three dimensional structures (3D) with sub-100 nm resolution. The technology is based on two-photon absorption; when the beam of an ultra-fast infrared laser is tightly focused into the volume of a photosensitive material, the polymerization process can be initiated by two-photon absorption within the focal volume. By moving the focused laser beam in a three-dimensional manner through the resin, 3D structures can be fabricated. The only processing required afterwards is the washing and removal of the non-illuminated, and therefore non-photopolymerized material.
We are investigating applications of nonlinear lihography in photonics, medical implants, and scaffolds for tissue engineering.