Comparison between a Ti cap cobalt silicide to a flashed Ti-Ti cap cobalt silicide

Cobalt silicide is used at contacts to reduce contact resistance and provide a low sheet resistance on gate, source and drain. This will improve device speed (lower RC delay). A titanium cap cobalt silicide (Ti/Co/Si) and flashed titanium-titanium cap cobalt silicide (Ti/Co/Ti/Si) solid phase epitaxy (SPE) are compared. Results revealed a transition from polycrystalline CoSi/sub 2/ to epitaxial CoSi/sub 2/ both in the (111) orientation if a flashed titanium is incorporated. The CoSi/sub 2/ nucleation temperature is decreased with the addition of flashed titanium.