Method of making enhanced trench oxide with low temperature nitrogen integration
US6727569B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 21, 1998 |
| Grant date | Apr 27, 2004 |
| Priority date | — |
| Expiry date | Apr 21, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76235
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A structure and an improved isolation trench between active regions within the semiconductor substrate involves forming on a silicon substrate and forming a nitride layer on the pad layer. Thereafter, a photoresist layer is patterned on the silicon nitride layer such that regions of the nitride layer are exposed where an isolation trench will subsequently be formed. Next, the exposed regions of the nitride layer and the pad layer situated below the exposed regions of the nitride layer are etched away to expose regions of the silicon substrate. Subsequently, isolation trenches are etched into the silicon substrate with a dry etch process. A trench liner is then formed and nitrogen incorporated into a portion of the trench liner to form an oxynitride layer. After formation of the oxynitride layer, the trench is filled with a dielectric preferably comprised of a CVD oxide. Thereafter, the CVD fill dielectric is planarized and the nitride layer is stripped away.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.