Hybrid trench isolation technology for high voltage isolation using thin field oxide in a semiconductor process
US6699772B1 · kind B1 · utility
Inventor
Key dates
| Filing date | Sep 18, 2002 |
| Grant date | Mar 2, 2004 |
| Priority date | — |
| Expiry date | Oct 21, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10B69/00
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for creating a trench for high voltage isolation begins by forming a trench in the substrate having sidewalls and a bottom surface. Spacers are formed along the sidewalls of a trench with the spacers partially covering the bottom surface. A barrier layer is formed on the portion of the bottom surface not covered by the spacers. The spacers are then removed, exposing the bottom surface not covered by the barrier layer. The bottom surface is then further etched to create a second deeper trench which has sidewalls and bottom surface. An insulating layer is then conformally deposited to cover the surface of the substrate including filling the first and second trenches.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.