Selective oxidation

Abstract

Abstract PURPOSE:To prevent unevenness of rise, etc., of an insulating oxide layer to be generated at the circumferential part of a mask to be caused by oxidation in the lateral direction of a substrate when the surface of the silicon substrate is to be oxidized selectively making a silicon nitride film as the mask for oxidation. CONSTITUTION:A resist film 2 having the desired pattern is formed on the silicon substrate 1, nitrogen ions are implanted therein to form an ion implanted layer 3 at the inside part of the surface of silicon substrate , and when heat treatment is performed, nitrogen ions lying scattered between lattices constitute the silicon nitride film 4. Oxidation treatment is performed making the nitride film 4 thereof as the mask to convert the silicon layer 1a on the nitride film 4 and the other surface of the silicon layer into oxide films 51, 52 respectively, and when the whole of surface is etched to remove the oxide film up to remove the silicon nitride film 4, the selective oxide films 52 having precise pattern can be formed.

Inventors

• 👤 Takeshi Ishihara
• 👤 Keiichi Kagawa

Bibliographic Details