Manufacture of semiconductor device

Abstract

Abstract PURPOSE:To prevent a field oxide film from being reduced at an etching operation by a method wherein, before an insulating film is formed, a protective film at the etching operation is formed, the insulating film is formed on it, the insulating film is then etched by an anisotropic etching operation and a sidewall spacer is formed. CONSTITUTION:After a gate electrode 5 and an n<-> diffusion layer 6 have been formed, a silicon nitride film 10 to be used as a protective film at an etching operation is formed in about 300Angstrom by a CVD method. Then, an anisotropic etching operation by RIE is executed; a sidewall spacer 8 is formed. At this time, an etching parameter is set in such a way that the difference in an etching rate between a silicon oxide film 4 and a silicon nitride film 10 is formed. When the etching rate is selected in this manner, the silicon nitride film 10 is not etched so much even when the silicon oxide film 4 is etched in order to form the sidewall spacer 8. As a result, a substratum field oxide film 3 is not etched. After that, ions are implanted by making use of the sidewall spacer 8 as a mask; an n<+> diffusion layer 9 is formed.

Inventors

• 👤 Jiyunko Yonemizu
• 👤 米水　順子

Bibliographic Details