Azobenzene-containing compounds were covalently attached onto Si(111) surfaces via Si−O linkages usinga two-step procedure. The modified Si(111) surfaces were characterized by X-ray photoelectron spectroscopy(XPS) and Fourier transform infrared (FT-IR) spectroscopy measurements. The monolayer surface showedpreferably chemical stability. Switchable photoisomerizability of azobenzene molecules on these modifiedsurfaces was observed in response to alternating UV and visible light exposure. The measured conductivityshowed distinct difference with trans and cis forms of azobenzene compounds on as-modified Si(111) surfaces.
