Trench device structure and fabrication
US7989293B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 24, 2009 |
| Grant date | Aug 2, 2011 |
| Priority date | — |
| Expiry date | Feb 24, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D64/663
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A vertical-current-flow device includes a trench which includes an insulated gate and which extends down into first-conductivity-type semiconductor material. A phosphosilicate glass layer is positioned above the insulated gate and a polysilicon layer is positioned above the polysilicate glass layer. Source and body diffusions of opposite conductivity types are positioned adjacent to a sidewall of the trench. A drift region is positioned to receive majority carriers which have been injected by the source, and which have passed through the body diffusion. A drain region is positioned to receive majority carriers which have passed through the drift region. The gate is capacitively coupled to control inversion of a portion of the body region. As an alternative, a dielectric layer may be used in place of the doped glass where permanent charge is positioned in the dielectric layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.