Coating process of ZnO thin film on macroporous silica periodic array

• Published in: Thin solid films 2006-05, Vol.504 (1), p.41-44
• Main Authors: Cheng, Y.H., Teh, L.K., Tay, Y.Y., Park, H.S., Wong, C.C., Li, S.
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electron and ion emission by liquids and solids; impact phenomena; Exact sciences and technology; Field emission, ionization, evaporation, and desorption; Fundamental areas of phenomenology (including applications); Optical materials; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optics; Photonic bandgap materials; Photonic crystals; Physics; Silica periodic array; Sol-gel; Thin film; ZnO
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2005.09.113

ZnO was deposited onto a 3D ordered macroporous SiO 2 structure using sol-gel method with reverse dip-coating. It was observed that a very thin layer of ZnO film formed on the surface of the macroporous SiO 2 using field emission scanning electron microscopy (FESEM). This thin layer was approximately 70 nm thick. The layer was near transparent, clearly revealing the macroporous SiO 2 structure underneath. The formation of this ZnO thin film suggests that miniscule air spheres trapped within the pores of the SiO 2 structure prevent the ZnO precursor sol from entering into these preoccupied positions. This unique structure can probably serve as an embedded planar defect for photonic crystals in the future and is believed to exhibit unusual photonic and luminescence properties which hold novel future applications.