A method for fabricating a semiconductor device comprising simultaneous growing of epitaxial and polycristalline Si layers over a selectively oxydized Si substrate, by vapor deposition

Abstract

Abstract An epitaxial silicon layer (4) is formed on a surface of a silicon substrate (1) simultaneously with the forming of a polycrystalline silicon layer (5) on a silicon dioxide (SiO₂) layer (3), previously formed on the silicon substrate (1) using a low pressure silicon vapor deposition method, employing a silicon hydride gas, particularly disilane (Si₂H₆), as a silicon source gas. The crystal growing temperature is comprised between 780°C to 950°C and a reaction gas pressure ranging from 30 torrs to 300 torrs is preferred. An extended silicon epitaxial region (a) is achieved under a higher temperature and a higher gas pressure, and with a substrate (1) of (1 0 0) orientation. A polysilicon layer (5) having an even surface and joining smoothly to the epitaxial silicon layer (4) which is simultaneously formed, is obtained under a lower temperature and a lower gas pressure, and with a substrate (1) of a (1 1 1) orientation.

Inventors

• 👤 Fumitake Mieno
• 👤 Kazuyuki Kurita
• 👤 Shinji Nakamura
• 👤 Atuo Shimizu

Bibliographic Details