Process for producing semiconductor device and semiconductor device produced thereby
US6858515B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 12, 2003 |
| Grant date | Feb 22, 2005 |
| Priority date | — |
| Expiry date | Oct 3, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D62/117
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A semiconductor device free from electric failure in transistors at upper trench edges can be produced by a simplified process comprising basic steps of forming a pad oxide film on the circuit-forming side of a semiconductor substrate; forming an oxidation prevention film on the pad oxide film; removing the oxidation presention film and the pad oxide film at a desired position, thereby exposing the surface of the semiconductor substrate; horizontally recessing the pad oxide film, etching the exposed surface of the semiconductor substrate by isotropic etching; forming a trench to a desired depth, using the oxidation prevention film as a mask; horizontally recessing the pad oxide film; oxidizing the trench formed in the semiconductor substrate; embedding an embedding isolation film in the oxidized trench; removing the embedding isolation film formed on the oxidation prevention film; removing the oxidation prevention film formed on the circuit-forming side of the semiconductor substrate; and removing the pad oxide film formed on the circuit-forming side of the semiconductor substrate, where round upper trench edges with a curvature can be obtained, if necessary, by conducting isotropi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.