Preparation and characterization of self-assembled monolayers of trichlorogermanyl propanoic acid and its derivatives

Self-assembled monolayers(SAMs) of trichlorogermanyl propanoic acid derivat ives on hydroxylated silicon substrates are prepared for the first time. Co ntact angle measurement, ellipsometry and X-ray photoelectron spectrometry( XPS) are used to characterize these SAMs, It is demonstrated that a quasi-2 D network is formed on the surface of the substrate after molecules adsorbe d on it. The molecular chains have certain tilt angles to the substrate sur face, The wettabilities of the SAMs are various,because the molecules adsor bed and liquids used in the experiments are different. It can be concluded that trichlorogermanes have similar self-assembly behavior as trichlorosila nes, Four SAMs are studied together: they are acid, ethyl, butyl and hexyl surfaces whose results are of good consistency.