3-stage method for forming deep trench structure and deep trench capacitor
US7094658B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 5, 2004 |
| Grant date | Aug 22, 2006 |
| Priority date | — |
| Expiry date | Sep 16, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10B12/0387
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for forming a deep trench structure comprises the steps of providing a silicon substrate; forming a mask layer of a predetermined pattern on the silicon substrate to expose a portion of the silicon substrate; forming a first trench in the exposed portion of the silicon substrate, the first trench having a first depth; forming a nitride layer on the surfaces of the whole structure; forming a second trench in the first trench downward, the second trench having a second depth greater than the first depth; forming another nitride layer on the surfaces of the whole structure; and forming a third trench in the second trench downward, the third trench having a third depth greater than the second depth. The method of the present invention can make the whole trench have better etch uniformity, thereby obtaining good electrical performance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.