Morphology and Structural Parameters of Three-Dimensional Structures Created Using STED Nanolithography
An original technique is presented for obtaining 3D nanostructures with the use of femtosecond two-photon photopolymerization and additional photopolimerization quenching STED nanolitography. The effect the degree of polymerization of the pentaerythritol tetraacrylate photoresist in combination with the 7-diethylamino-3-thenoylcoumarin photoinitiator (PETTA + DETC) has on its local mechanical properties is studied for photo- and thermopolymerized samples. Ways are proposed for measuring the degree of monomer conversion from IR-absorption spectra when comparing the hardness of the obtained polymer via atomic force microscopy, and for improving the mechanical properties of 3D nanostructures obtained via STED nanolitography with post-baking post-processing.