High density trench-based power MOSFETs with self-aligned active contacts and method for making such devices
US8951867B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 2012 |
| Grant date | Feb 10, 2015 |
| Priority date | — |
| Expiry date | Mar 31, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D64/2527
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Aspects of the present disclosure describe a high density trench-based power MOSFET with self-aligned source contacts. The source contacts are self-aligned with a first insulative spacer and a second insulative spacer, wherein the first spacer is resistant to an etching process that will selectively remove the material the second spacer is made from. Additionally, the active devices may have a two-step gate oxide, wherein a lower portion of the gate oxide has a thickness T2 that is larger than the thickness T1 of an upper portion of the gate oxide. It is emphasized that this abstract is provided to comply with rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.