Semiconductor device, mask for impurity implantation, and method of fabricating the semiconductor device
US7315062B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 30, 2005 |
| Grant date | Jan 1, 2008 |
| Priority date | — |
| Expiry date | Mar 1, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D64/111
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A semiconductor device includes: a semiconductor substrate having a source region and a drain region; and an offset region that is provided in the semiconductor substrate and extends from an edge of a gate electrode toward the drain region. The offset region includes multiple regions having different impurity concentrations formed by an ion implantation with a mask having an opening ratio that changes from the gate electrode to the drain region and by subsequent thermal treatment. The multiple regions include a concentration gradient region that is interposed between adjacent ones of the multiple regions and has the impurity concentration that gradually changes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.