Surface texture modification of spin-coated SiO2 xerogel thin films by TMCS silylation

The SiO2 xerogel thin films were deposited successfully by sol–gel technique via the acid-catalyzed hydrolysis and condensation of tetraethylorthosilicate (TEOS) with ethanol as a solvent. Further, the deposited thin films were treated wet chemically by trimethylchlorosilane (TMCS) and hexane solution with 10% and 15% volume ratio to remove the hydroxyl groups from the surface of deposited SiO2 thin films. These as deposited and surface-modified films were characterized by ellipsometer, Fourier transform infrared (FTIR) spectrometer and contact angle meter. The presence of 2900 and 850 cm−1 peaks of CH3 vibrations in FTIR spectra of surface-modified films confirms the hydrphobisation of SiO2 surface. The maximum contact angle of 108·7° was observed for the surface-modified film at 10% TMCS.