title: Inward-growing self-assembly of colloidal crystal films on horizontal substrates.
abstract: Colloidal crystal films have been fabricated on solid substrates with a horizontal deposition method. Scanning electron microscope images showed that the colloidal crystal films exhibit ordered face-centered cubic structures in large domains. Optical measurements demonstrated the presence of photonic band gap along the crystallographic [111] direction. The fabrication method described in this paper allows one to rapidly fabricate colloidal crystal films of different thicknesses, which can be controlled by varying colloidal suspension concentration or volume. In addition, the method also works well for growing colloidal crystal films on a hydrophilic solid substrate with a rough surface. Furthermore, the fabrication of colloidal crystal heterostructures has been demonstrated. An inward-growing mechanism responsible for self-assembly of colloidal spheres on horizontal substrates has been proposed to interpret the observed experimental results.
authors.affiliation: Department of Chemical and Biomolecular Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260.
authors.forename: Qingfeng
authors.initials: Q
authors.lastname: Yan
authors.forename: Zuocheng
authors.initials: Z
authors.lastname: Zhou
authors.forename: X S
authors.initials: XS
authors.lastname: Zhao
mesh_terms: D003102:Colloids; D003460:Crystallization; D008855:Microscopy, Electron, Scanning; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D013057:Spectrum Analysis
chemical_list: D003102:Colloids