Electronic structure and chemical composition of thin films forming at europium deposition on Si(100)2 x 1 surface at room temperature

Thin-film Eu-Si(100) structures formed by vacuum deposition of europium at room temperature onto a monocrystal silicon surface were studied by the method of photoelectron spectroscopy using synchrotron radiation. Analysis of the spectra showed that adsorption of even a small amount of metal (θ 0.2 monolayer) leads to destruction of the surface asymmetric dimers. It is found that deposition of europium is accompanied by the formation of a disordered metal film containing dissolved Si atoms. The concentration of silicon in the film decreases with the distance from the Eu-Si interface. Photoelectron spectra of the Si 2p core level of dissolved Si atoms are shifted toward lower binding energies as compared to the similar spectra of clean silicon surface