Stress enhanced MOS transistor and methods for its fabrication
US7534689B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 21, 2006 |
| Grant date | May 19, 2009 |
| Priority date | — |
| Expiry date | May 25, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D84/038
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A stress enhanced MOS transistor and methods for its fabrication are provided. In one embodiment the method comprises forming a gate electrode overlying and defining a channel region in a monocrystalline semiconductor substrate. A trench having a side surface facing the channel region is etched into the monocrystalline semiconductor substrate adjacent the channel region. The trench is filled with a second monocrystalline semiconductor material having a first concentration of a substitutional atom and with a third monocrystalline semiconductor material having a second concentration of the substitutional atom. The second monocrystalline semiconductor material is epitaxially grown to have a wall thickness along the side surface sufficient to exert a greater stress on the channel region than the stress that would be exerted by a monocrystalline semiconductor material having the second concentration if the trench was filled by the third monocrystalline material alone.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.