Characterization of Low Pressure Chemical-Vapor-Deposited Titanium Nitride from Metalorganic Sources

TiN films were grown by CVD from the reaction of tetrakis-diethylamino-titanium (TDEAT) with ammonia and tetrakis-dimethylamino-titanium (TDMAT) with ammonia. Deposited films were characterized by growth rate, resistivity, surface morphology and step-coverage over contact structures. Films deposited without ammonia flow were unstable in atmosphere and Auger analysis showed higher relative carbon content. Higher deposition pressure has a tendency to reduce the resistivity but also produces rough films. Films appear smooth at low deposition temperature and low pressure. The deposition process and resulting TiN layers are successfully integrated in a CVD-W plug fill application.