New silicide interface model from structural energy calculations.

Local density functional calculations have been employed to study the energies of the epitaxial (111) interfaces Si - NiSi sub 2 and Si - CoSi sub 2. For NiSi sub 2, the widely accepted interface structure with 7-fold coordinated Ni has the lowest energy. For CoSi sub 2, however, a new structure with 8-fold coordinated Co has the lowest energy, and the widely discussed 5-fold structure is seen to be extremely unfavorable.