
US Patent No: 6,093,951
Number of patents in Portfolio can not be more than 2000
MOS devices with retrograde pocket regions
Stats
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Jul 25, 2000
Issued date -
Jun 30, 1997
filing date -
08/885,102
serial no -
Expired
status
Importance
Abstract
Disclosed is a low threshold asymmetric MOS device having a pocket region with a graded concentration profile. The pocket region includes a relatively high dopant atom concentration (of the same conductivity type as the bulk region) abutting either the device's source or its drain along the side of the source or drain that faces the device's channel region. The pocket region's graded concentration profile provides a lower dopant concentration near the substrate surface and an increasing dopant concentration below that surface. This provides a relatively low resistance conduction path through the pocket region, while allowing the device's threshold voltage to be somewhat higher at the pocket region. The asymmetric device can also include a counter dopant region located beneath its substrate surface. This forces current to flow in the substrate but just above the region of high counter dopant concentration, where the resistance is relatively low.
First Claim
Related Publications
International Classification(s)
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Cited Art
| Patent Info | (Count) | # Cites | Year |
|---|---|---|---|
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| 5,773,863 Low power, high performance junction transistor | 66 | 1994 | |
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| 5,744,994 Three-terminal power mosfet switch for use as synchronous rectifier or voltage clamp | 47 | 1996 | |