| Abstract
| - Controlled growth of silicon dioxide (SiO2) using tetrachlorosilane (SiCl4) and water as precursors ontris(trimethylsiloxy)chlorosilane (trisTMSCl)-modified silicon wafer templates was studied. By manipulatingthe kinetics of the vapor-phase reaction of trisTMSCl with silicon wafers, surfaces with varying densitiesand distributions of unreacted silanols (in nanoholes) were obtained. Subsequent treatment with SiCl4/H2O led to site-specific growth of silica from the nanoholes that was monitored by atomic force microscopy(AFM). Different nanoscale structures with varying surface roughness and wettability were fabricated bycontrolling the growth kinetics. Modification of the newly grown silica with tridecafluoro-1,1,2,2-tetrahydrooctyldimethylchlorosilane (FDCS) allowed the growth kinetics to be followed by X-rayphotoelectron spectroscopy. Chemical etching effectively removed the organic residues, resulting inhydrophilic silica surfaces with nanoscale roughness. Further modification with FDCS rendered the surfaceshydrophobic. Water contact angle analysis and AFM clearly indicate that nanometer scale topography hasa profound effect on surface wettability.
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