An electrode on a semiconductor substrate includes a polysilicon layer, a silicon-implanted
layer on the polysilicon layer, a tungsten nitride layer on the silicon-implanted
layer, a tungsten nitride layer on the silicon-implanted layer, and a tungsten
layer on the tungsten nitride layer. The layer between the polysilicon layer and
the tungsten nitride layer may be either a tungsten silicon nitride layer or a
silicon-germanium layer.