Formation of shallow trench isolation (STI)
US6194285A · kind A · utility
18Cited by
16References
33Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 4, 1999 |
| Grant date | Feb 27, 2001 |
| Priority date | — |
| Expiry date | Oct 4, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76237
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method is disclosed to form a shallow trench isolation (STI) having reduced junction leakage by avoiding undercutting near the shoulder of the trench. This is accomplished by using the pad oxide as a screen oxide and not removing it by wet dip etch as is normally practiced. Instead, an extra layer of low temperature oxide is added through thermal growth, and then the resulting composite is removed together with minimal undercutting at the shoulder corners of the trench. Subsequently, gate oxide is grown thermally to complete the forming of the STI.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.