Synthesis of Monosized Silica Microparticles and Fabrication of Size-Controlled Silicon Microwires

The present study has been carried out to fabricate size-controlled monodisperse silica microparticles and SiMW arrays using a silica template via the nanosphere lithography (NSL) technique in accumulation to the metal-catalysed electroless etching (MCEE) technique. Considering the need, importance, and benefits of monosized SiO₂ microparticles as proclaimed in the scientific area with diverse industrial applications, monodispersed silica particles were synthesized by using modified Stober process. Synthesis of monosized microparticles has been achieved by using a silica precursor tetraethyl orthosilicate (TEOS) in an ethanol solution underneath basic conditions and assimilating a surfactant. In this process, a single monolayer closed-pack configuration of SiO₂ microparticles via self-assembled mechanism formed on the 2-inch silicon wafer by using a simple spin coating technique, and further, non-closed-packed structure was obtained from the closed-packed structure using the reactive ion etching (RIE) process. Using the MCEE technique, the size-controlled SiMW arrays were synthesized. The size and morphology of the microparticles and SiMW arrays were examined by the field-emission scanning electron microscope (FESEM). The SiMW arrays showed less than 15% reflection in the wide range of spectrum (300–1000 nm). The surface composition of the microparticles and SiMWs was studied using FT-IR. Such SiMW arrays may have several potential applications including solar cells.