Fabrication of highly qualified opal film with controlled thickness

Abstract

Stable dispersions of monodisperse colloidal PS spheres of submicron-size have been synthesized according to a general emulsion polymerization procedure for PBG crystals. The size of the PS spheres can be controlled by the amounts of surfactant and monomer. The periodically ordered three-dimensional porous structure having submicron PS spheres was obtained using a precisely controlled withdrawing method in which the fabrication of the template and the infiltration of the voids of the template are controlled by the related experimental parameters for the assembly, including the temperature, concentrations, and withdrawing speed. SEM (scanning electron microscope) images and transmission spectra of the samples show that these films have a highly ordered three-dimensional structure. The transmission spectra of the films, obtained upon changing the incident angle, favorably coincided with results calculated using the Bragg and Snell law.