Fabrication and Characterization of Two-Photon Polymerized Features in Colloidal Crystals


  • This material is based upon work supported by the U. S. Army Research Laboratory and the U. S. Army Research Office grant DAAD19–03–1–0227, the National Science Foundation grant DMR 00–71645, and the U.S. Department of Energy, Division of Materials Sciences grant DEFG02–91ER45439, through the Frederick Seitz Materials Research Laboratory at the University of Illinois at Urbana-Champaign (UIUC). This work was carried out in part in the Beckman Institute Microscopy Suite, UIUC and the Center for Microanalysis of Materials, UIUC, which is partially supported by the U.S. Department of Energy under grant DEFG02–91-ER45439. We gratefully acknowledge Dr. L.-S. Tan (U.S. Air Force Research Laboratory) for providing AF-350, K. Garsha for advice and assistance with confocal microscopy, and Dr. F. García-Santamaría of our laboratory for experimental assistance. Supporting Information is available online from Wiley InterScience or from the author.


The fabrication and characterization of two-photon polymerized features written within and outside of colloidal crystals is presented. Two-photon polymerization (TPP) response diagrams are introduced and developed to map the polymerization and damage thresholds for features written via modulated beam rastering. The use of tris[4-(7-benzothiazol-2-yl-9,9-diethylfluoren-2-yl)phenyl]amine (AF-350) as an initiator for TPP is demonstrated for the first time and TPP response diagrams illustrate the polymerization window. These diagrams also demonstrate that the polymerization behavior within and outside of colloidal crystals is similar and electron microscopy reveals nearly identical resolution. Fluorescence confocal microscopy further enables visualization of non-self-supporting, three-dimensional TPP features within self-assembled photonic crystals. Finally, microspot spectroscopy is collected from a two-photon feature written within a colloidal crystal and this is compared with simulation.