Semiconductor device

Abstract

Abstract PURPOSE:To enable a source/drain contact to be formed easily by providing a recessed part on a semiconductor substrate, a gate electrode with a round lower-part peripheral edge at the recessed part, and then a source and a drain regions on the surface of the semiconductor substrate. CONSTITUTION:An opening is formed by coating an Si3N4 film 12 on an Si substrate 11. The Si substrate 11 is subjected to anisotropic dry etching with the Si3N4 film 12 as an etching mask. Then, with the Si3N4 film 12 as an etching mask, the Si substrate 11 is further subjected to wet etching, thus forming a recessed part whose bottom part is no flat. After that, the Si3N4 film 12 which is used as an etching mask is eliminated and an SiO2 film 13 for a gate is formed by thermal oxidation. Then, a poly Si film 14 and a tungsten polycide is laminated, patterning is made, and then a gate electrode is formed within the previously formed recess. After that, after a source/drain diffusion layer is formed by ion-implantation, an MOS semiconductor integrated circuit is formed.

Inventors

• 👤 Makoto Nakamura
• 👤 誠 中村

Bibliographic Details