MOSFET termination trench
US9935193B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 20, 2015 |
| Grant date | Apr 3, 2018 |
| Priority date | — |
| Expiry date | Mar 20, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D64/256
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method, in one embodiment, can include forming a core trench and a termination trench in a substrate. The termination trench is wider than the core trench. In addition, a first oxide can be deposited that fills the core trench and lines the sidewalls and bottom of the termination trench. A first polysilicon can be deposited into the termination trench. A second oxide can be deposited above the first polysilicon. A mask can be deposited above the second oxide and the termination trench. The first oxide can be removed from the core trench. A third oxide can be deposited that lines the sidewalls and bottom of the core trench. The first oxide within the termination trench is thicker than the third oxide within the core trench.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.