Split-gate trench power MOSFET with self-aligned poly-to-poly isolation
US11848378B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 12, 2021 |
| Grant date | Dec 19, 2023 |
| Priority date | — |
| Expiry date | Dec 6, 2041 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D64/2527
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A semiconductor substrate has a trench extending from a front surface and including a lower part and an upper part. A first insulation layer lines the lower part of the trench, and a first conductive material in the lower part is insulated from the semiconductor substrate by the first insulating layer to form a field plate electrode of a transistor. A second insulating layer lines sidewalls of the upper part of said trench. A third insulating layer lines a top surface of the first conductive material at a bottom of the upper part of the trench. A second conductive material fills the upper part of the trench. The second conductive material forms a gate electrode of the transistor that is insulated from the semiconductor substrate by the second insulating layer and further insulated from the first conductive material by the third insulating layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.