Semiconductor device and method of manufacturing same
View Patent ↗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.
1. A method of manufacturing a semiconductor device comprising:
forming a gate insulating film on a semiconductor substrate;
forming a polysilicon layer on said gate insulating film;
forming a tungsten layer on said polysilicon layer;
implanting germanium into said tungsten layer to form a germanium-implanted layer between said polysilicon layer and said tungsten layer;
thermally treating said tungsten layer and said germanium-implanted layer in an ambient of one of nitrogen and ammonia to convert said tungsten layer into a tungsten nitride layer and said germanium-implanted layer into a silicon-germanium layer; and
forming a tungsten layer on said tungsten nitride layer.