Split-gate trench power MOSFET with protected shield oxide
US9281368B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 12, 2014 |
| Grant date | Mar 8, 2016 |
| Priority date | — |
| Expiry date | Dec 12, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D84/83
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A plurality of gate trenches is formed into a semiconductor substrate in an active cell region. One or more other trenches are formed in a different region. Each gate trench has a first conductive material in lower portions and a second conductive material in upper portions. In the gate trenches, a first insulating layer separates the first conductive material from the substrate, a second insulating layer separates the second conductive material from the substrate and a third insulating material separates the first and second conductive materials. The other trenches contain part of the first conductive material in a half-U shape in lower portions and part of the second conductive material in upper portions. In the other trenches, the third insulating layer separates the first and second conductive materials. The first insulating layer is thicker than the third insulating layer, and the third insulating layer is thicker than the second.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.