Patent ID: 6524975
Filing Date: 2003-02-25
Classification: C23C,H01L

Abstract:
A method of manufacturing a gate stack or digit line with a protective silicon oxide-type film or silicon nitride-type film on a semiconductor substrate, the method comprising:providing a semiconductor substrate; isolating an active region on the semiconductor substrate; forming a gate stack or digit line on the active region, said gate stack or digit line having sidewalls and at least one horizontal surface; disposing said substrate within a reaction zone of a high density plasma reactor; introducing a gas mixture containing a silicon compound and at least one other reactant gas capable of reacting with said silicon compound to form either silicon nitride or silicon oxide into said reaction zone containing said substrate, wherein said silicon compound is introduced at a flow rate in the range of about 40 to about 400 sccm; maintaining the pressure in said zone from about 0.1 to about 100 millitorr and the temperature in said zone from about 350Â° C. to about 650Â° C.; biasing the substrate with a first RF power while exciting said gas mixture with a high density plasma for a period of time sufficient to form a first layer of silicon oxide or silicon nitride film on said substrate; and after forming said first layer of silicon oxide or silicon nitride film, biasing the substrate with a second RF power while exciting said gas mixture with a high density plasma, wherein said first and second RF powers are selected to control the thicknesses of the silicon nitride or silicon oxide film so as to provide a film of about 1000 to about 3000 angstroms thick on said at least one horizontal surface of said gate stack or digit line and a film of about 100 to about 900 angstroms thick on the sidewalls of said gate stack or digit line.