In this study, high-quality colloidal photonic crystals with sub-micrometer sized colloidal particles as a building block were fabricated via new routes and the applications using the prepared colloidal crystals were demonstrated.

In chapter 2, w ...

In this study, high-quality colloidal photonic crystals with sub-micrometer sized colloidal particles as a building block were fabricated via new routes and the applications using the prepared colloidal crystals were demonstrated.

In chapter 2, we discussed a self-assembly method, referred to as confined convective assembly, for fabricating well-ordered two-dimensional (2D) and three-dimensional (3D) colloidal crystal films. With a minute amount of a polystyrene colloidal suspension (50 ？？L at on time) and without any special equipment, the proposed method can be used to rapidly deposit high-quality colloidal crystal films over a large surface area (1 cm ？e 1 cm). By controlling the lift-up rate of the substrate, we modulate the meniscus thinning rate, which determined whether the colloidal particles are assembled into two or three dimensions. The proposed method can be used to fabricate not only monolayered colloidal crystals with colloidal particles of various sizes, but also multilayered colloidal crystals. In addition, the method enables us to fabricate binary colloidal crystals by consecutively deposing large and small particles.

In chapter 3.1., we demonstrated that two-dimensional polystyrene colloidal crystals of much higher quality can be fabricated in a single-step confined convective assembly process by introducing water-soluble (viscoelastic material) polymer into the colloidal suspension. The presence of the water-soluble polymer in the aqueous phase enables the colloidal particles to arrange into more hexagonally close-packed single crystalline domains, and thus reduces the defect density. In addition, the physical stability of the final two-dimensional colloidal crystals is improved because each particle is bonded to neighboring particles. In chapter 3.2., we have fabricated robust, high-quality 3-D colloidal crystals using the vertical deposition by introducing a water-soluble polymer into the colloidal suspension. Compared to three-dimensional colloidal crystals grown in the absence of water-soluble polymer, the three-dimensional colloidal crystals grown from suspensions containing water-soluble polymer have an even surface over the entire substrate and show greatly improved crystals quality with fewer cracks and line-dislocations.

In chapter 4.1., we fabricated various binary colloidal crystals via the confined convective assembly method by using the two-dimensional colloidal crystals as templates for the epitaxial growth of colloidal particles. By adjusting the ratio of the diameters of the small and large particles as well as the concentration of the small colloidal particles, we fabricated binary colloidal crystals with various superlattices, including the previous reported structures, along with new and more complicated structures. The present results show that the confined convective assembly is a very convenient and efficient approach for quickly fabricating high-quality binary colloidal over a large area using a very small amount of colloidal suspension. In chapter 4.2., we discussed on a fabrication of periodic nanostructures using poly(dimethylsiloxane) molds based on three-dimensionally ordered colloidal crystals. We prepared master molds using three-dimensionally ordered colloidal crystals and poly(dimethylsiloxane) molds by their replications. We then transferred the patterns of the replica molds onto polystyrene thin films via a hot-embossing technique. We could fabricate hexagonally arrayed two-dimensional nanostructures using close-packed and non-close-packed three-dimensional colloidal crystals template. We also fabricated hexagonal arrays with new structure using inverted colloidal crystals template.

We first have described a self-assembly method for fabricating well-ordered two-dimensional and three-dimensional colloidal crystals films. This method was valid for the fabrication of mono-layered colloidal crystals with colloidal particles with coll ...

We first have described a self-assembly method for fabricating well-ordered two-dimensional and three-dimensional colloidal crystals films. This method was valid for the fabrication of mono-layered colloidal crystals with colloidal particles with colloidal particles of various sizes, and we also used this method to fabricate multilayered colloidal crystals. We have reported that the quality and the physical stability of the colloidal crystals produced using convective assembly can be greatly improved by introducing a water-soluble polymer. This improved quality and enhanced stability makes the colloidal crystals formed in the presence of water-soluble polymer potential candidates for used in other applications. By using high-quality 2D colloidal crystals as templates for the epitaxial growth of colloidal particles, we have fabricated various binary colloidal crystals. We believe that these binary colloidal crystals can be used as templates for planarized microphotonic crystal chips....