Mechanism of formation of ytterbium disilicide nanofilms on the Si(111) surface

Thin-film Yb–Si(111) structures have been studied experimentally for different film thicknesses and at substrate temperatures of 300–1500 K. The temperatures at which the formation of ytterbium disilicide begins and ends, the thermal stability, and the work function have been determined. It has been shown that yttrium disilicide is formed at relatively low temperatures. The mechanism explaining this fact has been proposed. This mechanism also explains why and in which manner ytterbium transforms silicon into silicide despite the fact that the bond between atoms in the silicon crystal is stronger than that in silicide.