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We study the nonwettability and transparency from the assembly of fluorosilane modified silica nanoparticles (F-SiO₂ NPs) via one-step spin-coating and dip-coating without any surface postpassivation steps. When spin-coating the hydrophobic NPs (100 nm in diameter) at a concentration ≥0.8 wt % in a fluorinated solvent, the surface exhibited superhydrophobicity with an advancing water contact angle greater than 150° and a water droplet (5 μL) roll-off angle less than 5°. In comparison, superhydrophobicity was not achieved by dip-coating the same hydrophobic NPs. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) images revealed that NPs formed a nearly close-packed assembly in the superhydrophobic films, which effectively minimized the exposure of the underlying substrate while offering sufficiently trapped air pockets. In the dip-coated films, however, the surface coverage was …