Patent ID: 6774047
Filing Date: 2004-08-10
Classification: H01L

Abstract:
A method of manufacturing a semiconductor integrated circuit device comprising the steps of:(a) providing a silicon wafer covered with an insulating film whose main surface is mainly silicon oxide; (b) cleaning a surface of said silicon wafer covered with the insulating film whose main an ordinary temperature with a processing solution which contains hydrogen peroxide, hydracid fluoride salt, and water, and also contains HF and HF2âˆ’ as etching seeds of the silicon oxide, under conditions that said insulating film is etched but said silicon wafer is not etched, the concentration of said hydracid fluoride salt being in the range of about 0.1 to 3 mol/l; (c) removing said insulating film after said step (b), thereby to expose the surface of said silicon wafer; and (d) subjecting said silicon wafer to a heat-treatment after said step (c), thereby to form a gate oxide film over said silicon wafer.