Temperature effects on pinpoint photopolymerization and polymerized micronanostructures

The spatial resolution in pinpoint two-photon photopolymerization of radical-type resins was found to be improved by varying the liquid sample temperature from a critical value T-c. For SCR-500 and NOA-61, the currently widely used resins, T-c is around room temperature. The improvement of spatial resolution by temperature decrease was attributable to restraint radicals diffusion; while the voxel size reduction versus temperature increase was considered as arising from enhanced chain termination. Furthermore, temperature plays an important role in size tuning of polymerized structures, for example, a photonic crystal blueshifted its working wavelength for 50 and 400 nm when heated at 200 and 300 degrees C, respectively, indicating the possibility to precisely tailor the photonic bandgap by means of thermal processing. (c) 2008 American Institute of Physics.