Coadsorption and three-component surface phases formation on silicon

In this report we would like to describe the different situations at coadsorption processes of different elements on Si surface and try to classify them using mainly the results which have been obtained in our department. It has been shown that new three-component surface phases are formed at equilibrium situation in the systems like Al--Au, Au--In, Au--Ag, In--Ag, and Al--Sb. One kind of adsorbate can crowd out the other during the coadsorption. This is illustrated for Al--H, Ag--H, Al--Au, Sb--Al, and others. Situation {open_quotes}change a partner{close_quotes} is shown on Al--N/Si(111) system. Aluminum displaces silicon from the silicon-nitride (nitrogen changes the partner) and forms aluminum-nitride epitaxial film on Si surface. The influence of the surface species on the epitaxial growth is also considered.