Bottom-drain LDMOS power MOSFET structure having a top drain strap
US7829947B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 17, 2009 |
| Grant date | Nov 9, 2010 |
| Priority date | — |
| Expiry date | Mar 17, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D64/258
Abstract
Lateral DMOS devices having improved drain contact structures and methods for making the devices are disclosed. A semiconductor device comprises a semiconductor substrate; an epitaxial layer on top of the substrate; a drift region at a top surface of the epitaxial layer; a source region at a top surface of the epitaxial layer; a channel region between the source and drift regions; a gate positioned over a gate dielectric on top of the channel region; and a drain contact trench that electrically connects the drift layer and substrate. The contact trench includes a trench formed vertically from the drift region, through the epitaxial layer to the substrate and filled with an electrically conductive drain plug; electrically insulating spacers along sidewalls of the trench; and an electrically conductive drain strap on top of the drain contact trench that electrically connects the drain contact trench to the drift region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.