The self-assembled (SA)molecular monolayers of a 3-aminopropyltrimethoxysilane (3-APTS) on a silicon (111) surface, and the?effects of ultraviolet (UV) pre-treatment for substrates on the assembling process have been studied using XPS and atomic?forcemicroscopy (AFM). The results show that the SA 3-APTS molecules are bonded to the substrate surface in a nearly vertical?orientation, with a thickness of the monolayer of about 0.8–1.5 nm. The SA molecular monolayers show a substantial degree?of disorder in molecular packing, which are believed to result from the interactions of amine tails in the silane molecules used?with surface functionalities of the substrates, and the oxygen-containing species from the ambient. UV irradiation for silicon?substrates prior to the self-assembly reaction can enhance the assembly process and hence, significantly increase the coverage?of themonolayer assembled for the substrates.
Nai-Yi Cui,Chaozong Liu,Wantai Yang
Surface and Interface Analysis