Method of manufacturing a semiconductor device,in which a silicon wafer is provided at its surface with field oxide regions.

摘要

A method of manufacturing a semiconductor device, in which a surface (1) of a silicon wafer (2) is locally provided with an oxidation mask (3), whereupon the wafer is subjected to an oxidation treatment by heating it in an oxidizing gas mixture. According to the invention, the wafer is heated during the treatment in the oxidizing gas mixture to a temperature of 950 to 1050 DEG C. Water is then added to the oxidizing gas mixture. The quantity of added water is initially less than 30 % by volume and later larger. Thus, in a comparatively short time a comparatively thick layer of oxide can be formed without defects being formed in silicon lying under the oxide.