Claims
- 1. A semiconductor device manufacturing method, comprising the steps of:
- forming a first insulating film on a silicon element substrate in an SOI substrate by thermal oxidation of said silicon element substrate, wherein said SOI substrate includes a support substrate, said silicon element substrate, and a separating insulating film between said silicon element substrate and said support substrate;
- etching said silicon element substrate to form a trench, said trench having a bottom formed by a portion of said separating insulating film, and at least one side wall formed by at least one portion of said silicon element substrate;
- depositing a first polysilicon film upon a surface of said bottom, a surface of each of said at least one side wall of said trench, and said first insulating film;
- etching said first polysilicon film on said insulating film and on said bottom of said trench, using an anisotropic etching technique, to expose said first insulating film and a portion of said bottom, and to leave a portion of said polysilicon on said at least one side wall of said trench;
- etching and removing said exposed first insulating film; and
- depositing an oxidized insulating film on said silicon element substrate and in said trench, using chemical vapor deposition, to isolate said silicon element substrate.
- 2. The semiconductor device manufacturing method according to claim 1, wherein said first polysilicon film contains a dopant.
Priority Claims (1)
Number |
Date |
Country |
Kind |
7-328461 |
Dec 1995 |
JPX |
|
Parent Case Info
This application is a Division of Ser. No. 08/769,031 filed Dec. 17, 1996, U.S. Pat. No. 5,854,120.
US Referenced Citations (4)
Divisions (1)
|
Number |
Date |
Country |
Parent |
769031 |
Dec 1996 |
|