Electron-induced interaction of condensed chlorine with Si(100)

We have studied electron-induced interaction of molecular chlorine with Si(100) surface under ultra-high vacuum conditions. Without electron beam irradiation, chlorine was found to be adsorbed both dissociatively (first step) and molecularly (second step) at 100 K. Illumination of molecular chlorine-covered surface at 100K with electron beam (1–3 keV) led to the formation of silicon tetrachloride on the Si(100) surface. We established that the surface reaction, that is responsible for the SiCl4 formation, is initiated by Cl2 dissociation and appearance of the active chlorine radicals. Importance of the such effect is also discussed in a view of their possible applications for selective etching of semiconductor surfaces.