Bottom oxide formation process for preventing formation of voids in trench
US6974749B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 1, 2003 |
| Grant date | Dec 13, 2005 |
| Priority date | — |
| Expiry date | Oct 1, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D64/516
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Embodiments of the present invention are directed to a method of forming a bottom oxide layer in the trench in semiconductor devices, such as Double-Diffused Metal-Oxide Semiconductor (DMOS) devices. In one embodiment, a method of forming a bottom oxide layer in a trench structure comprises providing a semiconductor substrate; forming a silicon nitride layer on the semiconductor substrate; forming a first oxide layer on the silicon nitride layer; forming a trench structure in the semiconductor substrate; forming a second oxide layer on a bottom and sidewalls of the trench and on a surface of the first oxide layer; removing the first oxide layer and the second oxide layer on the surface of the silicon nitride layer; and removing the second oxide layer on the sidewalls of the trench and a portion of the second oxide layer on the bottom of the trench.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.