Effects of paraffin addition on characteristics of self-assembled SiO2 photonic crystals

The effects of silicon oil addition on the optical properties and crystallinity of self-assembled SiO2 photonic crystal were examined using a silica nanopowder. The silica nanopowder was fabricated using the well-known Stöber process. The photonic crystals were self-assembled by evaportation method. During the evaporation process, the nanopowder was 0.4 wt%, the process temperature was 80 °C, and the heattreatment temperature after evaporation was 100∼300°C. The addition of paraffin can reduce the defects in the photonic crystal layer resulting in good crystallinity and transmittance. It is believed that paraffin can enhance the bonding force between silica nanopowders.