Improving nickel silicide - silicon nitride adhesion through surface passivation

A process for forming nickel silicide 170 and silicon nitride 190 structure in a semiconductor integrated circuit device 110 is described. Good adhesion between the nickel silicide 170 and the silicon nitride 190 is accomplished by passivating the nickel silicide surface with nitrogen. The passivation may be performed by treating the nickel silicide surface with plasma activated nitrogen species. An alternative passivation method is to cover the nickel silicide with a film of metal nitride and heat the substrate to about 500° C. Another alternative method is to sputter deposit silicon nitride 190 on top of nickel silicide 170.