Method for increasing the performance of trenched devices and the resulting structure
US4893160A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 13, 1987 |
| Grant date | Jan 9, 1990 |
| Priority date | — |
| Expiry date | Nov 13, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D64/513
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A trenched device, such as a DMOS transistor, provides for higher breakdown voltages than possible using trenched devices of the prior art. The trench extends only into the epitaxial layer, thereby minimizing breakdown problems associated with prior art trench devices in which the trench extends into the more highly doped substrate. However, in order to achieve higher breakdown voltages, the dopant concentration is increased in that portion of the epitaxial layer surrounding the bottom of the trench. Thus, a novel trenched device is taught which achieves higher breakdown voltages by causing the trench to be surrounded by relatively highly doped material, while not requiring the trench to extend into the more highly doped substrate itself.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.