Refractory metal silicide formation induced by As⁺ implantation

Refractory metal silicides WSi2, TaSi2, and MoSi 2 have been successfully formed by implanting As+ through the respective metal films deposited on Si. These ion-beam-induced silicides can be formed on 〈100〉 single-crystal Si substrates as well as on polycrystalline Si films. The formation and annealing of these silicides have been studied by He+ backscattering, x-ray diffraction, and sheet resistivity measurements. Apparently both the ion beam bombardment and some elevation of temperature during implantation are essential for silicide formation. Annealing these ion-beam-induced silicides reduces their resistivity and changes their crystallographic structure. The redistribution of implanted As is also observed.