Surface band structure of aryl-diazonium modified p-Si electrodes determined by X-ray photoelectron spectroscopy and electrochemical measurements

Abstract

The influence of grafted organic layers, obtained by aryldiazonium cations reduction, on the surface properties of p-type silicon was investigated. These layers were characterized by X-ray photoelectron spectroscopy (XPS), infrared spectroscopy and electrochemical methods. The results indicate a passivation of the silicon surface, a decrease of the oxidation of silicon. The results from electrochemical and XPS measurements can be used together to quantify the shift of the surface energy bands of the semiconductor caused by the presence of these layers at the surface. These measurements are important to understand the interfacial properties of the semiconductor and this grafting method can thus be used to adjust the surface energy levels positions toward those of different chemical reactions.