The Fabrication Of 3D Silica Photonic Crystals In Visible Light Range

Photonic Crystals (PC) is a new kind of synthesized material, which could change its reflectance n at the scale of visible light (sub-micrometer). According to its spatial periodicity, PC can be sorted into 1-D PC, 2-D PC and 3-D PC. Because of its special structure, PC has some novel physical characters, such as photonic band gap, advanced phenomena. It also could prohibit the spontaneous emission. PC has attracted many scientists from the region of theoretical physics, optical and material science since it was first defined.In this thesis, we studied the fabrication and the characterization of the spherical particles of mono-dispersed SiO₂, and the opal structural PC. Main results are followed:1. We fabricated the spherical particles of mono-dispersed SiO₂ by improved stober's method .We succeeded in controlling the diameter by changing the concentration of ammonia. We also analyzed the diameter and the structure by TEM and XRD.2. Acetone was first time used as the dispersant, which dramatically shortened the cycle of the vertical deposition method. The photonic band gap of PC was measured by UV spectroscopy;and the surface and internal structure were characterized by SEM;They all showed that the PC were packed as face central cubic in the way of (111) facet. The transmission and reflectance spectrum of the sample showed a clear transmission valley/reflectance peak at 534 nm, indicating that the PC had a large photonic band gap in the range of visible wavelength. In addition, the effect of annealing procedure on band gap of PC was studied too.3. We fabricated the compound PC of SiO₂ covered by ZnO by the liquor pyrogenation method. About 222-nm-diameter silica sphere was covered by 13-nm-thickness ZnO, which leading the photonic band gap was changed from 482nm to 542nm.