Tailoring of Nano- and Microstructure in Biomimetically Synthesized Ceramic Films; Conference paper

摘要

A novel ceramic thin film deposition approach through which inorganic materials were deposited on a functionalized organic matrix from aqueous media at low temperatures was studied. This process is analogous to the natural biomineralization process. Specifically, nanostructured ZrO2 and TiO2 thin films were deposited at about 70 C by the hydrolysis of Zr(SO4)2 and TiCl4 aqueous precursor solutions, respectively, on silicon substrates coated with phosphonate-terminated self-assembled monolayers (SAMs). The as-deposited oxide films consisted of nanocrystallites of tetragonal ZrO2 and anatase phase TiO2 in size of 5-10 nm, while some amorphous phases existed as well. The principal mechanism for the formation of the films seems to be homogeneous nucleation of the bulk precipitates and their aggregation behavior in supersaturated solution. Different from the previous results, the ZrO2 and TiO2 films could also be deposited on bare silicon substrates without any SAMs, under the same conditions used for deposition on SAMs.