LOCOS type field isolating film and semiconductor memory device formed therewith
US5234859A · kind A · utility
6Cited by
3References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 3, 1991 |
| Grant date | Aug 10, 1993 |
| Priority date | — |
| Expiry date | Sep 3, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76202
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A LOCOS isolation film is formed on a major surface of a semiconductor substrate. Thereafter, a new surface of the semiconductor substrate is exposed by wet etching. A resist pattern is formed on the exposed new surface. A part of the LOCOS isolation film is removed using this resist pattern, to expose the surface of the semiconductor substrate. This unsymmetrical LOCOS isolation film increases the effective area of the surface of the semiconductor substrate and preserves predetermined dielectric resistance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.