An improved scanning probe-based lithography: Site-controlled formation of self-assembled film as an etch mask

Abstract A self-assembled 1H,1H,2H,2H-perfluorodecyltriethoxysilane (PFDS) film was prepared on a diamond tip scratched silicon surface, and presented stronger anti-etching ability during subsequent selective etching than direct scratch mask. The effect of self-assembly time, normal load in scratching and etching time on anti-etching performance of the PFDS film were investigated by comparing the height and topography of fabricated mesas. It was found that the self-assembly of 2 h was enough for the formation of PFDS film, and the increase of normal load in scratching could improve anti-etching ability of the film. The result of X-ray photoelectron spectroscopy (XPS) suggested that PFDS molecules were selectively adsorbed on scratched silicon surface. This study provides a novel route for site-controlled formation of self-assembled mask and helps produce higher nanostructures in selective etching, which is promising for constructing functionalized micro/nano devices.