CVD OF INTEGRATED Ta AND TaNx FILMS FROM TANTALUM HALIDE PRECURSORS

摘要

A chemical vapor deposition (CVD) method for depositing high quality conformal tantalum/tantalum nitride (Ta/TaNx) bilayer films from inorganic tantalum pentahalide (TaX5) precursors and nitrogen is described. The inorganic tantalum halide precursors are tantalum pentafluoride (TaF5), tantalum pentachloride (TaCl5) and tantalum pentabromide (TaBr5). A TaX5 vapor is delivered into a heated reaction chamber. The vapor is combined with a process gas to deposit a Ta film and a process gas containing nitrogen to deposit a TaNx film on a substrate that is heated to 300° C.-500° C. The deposited Ta/TaNx bilayer film is useful for integrated circuits containing copper films, especially in small high aspect ratio features. The high conformality of these films is superior to films deposited by PVD.