The silicon wafer null which improves manner and the surface roughness which improve the surface roughness of the silicon wafer

摘要

PROBLEM TO BE SOLVED: To improve both micro-roughness and haze level of a silicon wafer at the same time by heat treating of a mirror finished silicon wafer in oxidative atmosphere to form a thermal oxide film of specified thickness on the surface thereof and then removing the thermal oxide film. ;SOLUTION: A mirror finished silicon wafer is heat treated in oxidizing atmosphere to form a thermal oxide film of 300 nm thick or above on the surface thereof, and then the thermal oxide film is removed thus improving the surface roughness of the silicon wafer. Heat treatment in oxidizing atmosphere is suitably conducted at a relatively high temperature of 1,100-1,300°C in order to improve the haze level, while shortening the oxidation time. The thermal oxide film is suitably removed by etching the silicon wafer using an aqueous solution containing hydrofluoric acid, in order to remove the thermal oxide film easily at low cost. In this case, an aqueous solution having HF concentration of 10% or less is suitably employed.;COPYRIGHT: (C)1999,JPO