Method for forming heavy nitrogen-doped ultra thin oxynitride gate dielectrics

A method for forming an ultra thin gate dielectric for an integrated circuit device is disclosed. In an exemplary embodiment of the invention, the method includes forming an initial nitride layer upon a substrate by rapidly heating the substrate in the presence of an ammonia (NH 3 ) gas, and then re-oxidizing the initial nitride layer by rapidly heating the initial nitride layer in the presence of a nitric oxide (NO) gas, thereby forming an oxynitride layer. The oxynitride layer has a nitrogen concentration therein of at about 1.0×10 15 atoms/cm 2 to about 6.0×10 15 atoms/cm 2 , and has a thickness which may be controlled within a sub 10 range.