Physics of metal silicides: Stability, stoichiometry, and schottky barrier control

Using theoretical calculations, we explain why some metal atoms like Ni produce bulk silicides and the others such as Au never produce silicides, why silicides with some stoichiometry are difficult to grow on Si substrate, why Schottky barrier for electrons simply decreases as the Si ratio in silicides increases, and how the dopants change Schottky barrier. It is shown that the keys to answer these questions are (i) the electron transfer from Si-p to metal-atom-d orbitals and (ii) the energy losses by elastic strain and bond-breaking at the interface.