A Novel Multibranched Chromophore Containing Carbazole Moiety for Two-Photon Microfabrication

A novel multibranched chromophore containing carbazole moiety，4, 4´, 4´´-tris(9-carbazyl-trans-styryl) triphenylamine (TCSTPA)，was synthesized and characterized by 1HNMR and elemental analysis. A larger two-photon absorption (TPA) cross section of the chromophore was obtained as high as 2350 GM compared to that of the traditional linear chromophore when pumped by a femtosecond laser at 800 nm. Microstructure based on TPA induced polymerization with a spatial resolution of submicron was fabricated under much lower incident laser power using TCSTPA as a TPA photoinitiator and a multifunctional resin of pentaerythritol triacrylate (PETA) as a polymerizable monomer. The result indicates potential applications of this kind of chromophores with multibranched structural motif in the fabrication of polymer and functional microdevices.