Large-Area Self-Assembled Monolayer of Silica Microspheres by Convective Assembly

Abstract:

We reported here a convective assembly process for the formation of large-area self-assembled monolayers of silica microspheres on silicon and glass substrates. Uniformly coated monolayers of silica spheres were achieved on silicon wafers with and without coated SiN₂ of 3 inch of diameter and large glass substrate of 6 × 6 in² in size. The coating of large-area uniform monolayers of silica microspheres was characterized with scanning electron microscopy and optical microscopy. The mechanism of the convective assembly has been explained by the convective flux that is generated by capillary immersion force caused from the solution evaporation and hydrodynamic drag force. The patterns of silica microspheres were transferred to the silicon substrates using a deep reactive ion etching technique. It is found that textured silicon reduced the reflectance of silicon substrate from 52.2% to 33.2% around 400 nm and from 33.9% to 19.5% around 1,100 nm. The rapid self-assembled monolayer with silica microspheres provided a glimpse at the wide range of coating and photonic device applications where convective assembly can be used.

• Periodical: Key Engineering Materials (Volumes 609-610)
• Pages: 479-482
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.609-610.479
• Online since: April 2014
• Authors: Yue Hui Wang
• Keywords: Convective Assembly, Reactive Ion Etching, Self-Assembly, Silica Microsphere

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