Heteroepitaxial growth of high-k gate oxides on silicon: insights from first-principles calculations on Zr on Si(0 0 1)

Metal deposition of Zr on a Si(0 0 1) surface has been studied by state-of-the-art electronic structure calculations. The energy per Zr adatom as a function of the coverage shows, that Zr forms silicide islands even at low coverages. Adsorbed Zr is thermodynamically unstable against the formation of bulk silicide ZrSi2. The observation that the islands consist of structural elements of the bulk silicide is an indication that silicide grains will form spontaneously.