Method of forming nitride films with high compressive stress for improved PFET device performance

摘要

A method is provided for making a FET device in which a nitride layer overlies the PFET gate structure, where the nitride layer has a compressive stress with a magnitude greater than about 2.8 GPa. This compressive stress permits improved device performance in the PFET. The nitride layer is deposited using a high-density plasma (HDP) process, wherein the substrate is disposed on an electrode to which a bias power in the range of about 50 W to about 500 W is supplied. The bias power is characterized as high-frequency power (supplied by an RF generator at 13.56 MHz). The FET device may also include NFET gate structures. A blocking layer is deposited over the NFET gate structures so that the nitride layer overlies the blocking layer; after the blocking layer is removed, the nitride layer is not in contact with the NFET gate structures. The nitride layer has a thickness in the range of about 300-2000 Å.