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Preparation and Properties of Silica Inverse Opal via Self-Assembly

The bottom-up colloidal synthesis of photonic band gap (PBG) materials or photonic crystals (PC) has attracted considerable interest as compared to so-called top-down lithographic approaches due to the simple processing steps involved and the prospect of the economically viable production of complex 3-dimensional optical materials from simple colloidal particles. To date self-assembly techniques constitute the most popular approach to fabricate 3D photonic crystals from colloidal particle suspensions. Based on the natural tendency of monodisperse colloidal particles to organise into ordered arrays, this method represent the best option due to the ease of fabrication, ability to produce larger area samples and cost. Here we report on the fabrication of long range three-dimensional (3D) ordered poly (methyl methacrylate) (PMMA)-silica PC structures and the subsequent fabrication of robust silica inverse opals using self-assembly methods. The optical properties of these materials are described and discussed in terms of potential applications of these materials.