Abstract: A method of forming an ultra-thin gate dielectric by soft nitrogen-containing plasma. The method comprises a pre-nitridation step nitrifying a substrate surface by soft nitrogen-containing plasma, and a thermal oxidation step oxidizing the substrate surface to form an ultra-thin gate dielectric on the substrate surface. The plasma density of the soft nitrogen-containing plasma is about 109-1013 cm−3.

Abstract: A method for forming a gate dielectric layer by a single wafer process is provided. The method for forming a gate dielectric layer by a single wafer process is accomplished by two steps respectively performed in a single-wafer chamber and a single-wafer rapid thermal processing (RTP) chamber. First, by placing a silicon wafer in the single-wafer chamber and performing a nitridation process to form a nitrogen-contained silicon oxide layer on the surface of the silicon wafer. Then, placing the silicon wafer in the single-wafer RTP chamber and performing an in-situ steam generation (ISSG) oxidation process to oxidize the nitrogen-contained silicon oxide layer to a silicon oxide layer with an oxynitride bottom layer serving for a gate dielectric layer.