US6218708B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Back-biased MOS device and method
Assignee: Oracle America Inc
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Filing: 1998-02-25
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Granted: 2001-04-17
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Expires: 2018-02-25
Abstract
Abstract An MOS device has source and drain regions of a first conductivity formed in a well of a second conductivity, the well of the second conductivity being formed in an upper surface of a bulk material of the first conductivity. Source and drain potentials are applied to the source and drain regions, respectively, while a separate bias potential is routed to the well through a conductive sub-surface layer of the second conductivity which is located spaced from and beneath an upper surface of the bulk material and which is shorted to the well.
Inventors
- 👤 James B. Burr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 14:22
CPC Classifications
H; H10; H10D; H10D84/00; H10D84/80; H10D84/82; H10D84/83; H10D84/85; H10D62/00; H10D62/10; H10D62/17; H10D62/351; H10D62/357; H10D62/364; H10D62/378
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
118 words
An MOS device comprising: a bulk material of a first conductivity having a principal surface; a well of a second conductivity formed in said principal surface of said bulk material; source and drain regions of the first conductivity formed in said well to define a channel region therebetween; a first conductive sub-surface layer of the second conductivity spaced from and beneath said surface of said bulk material and contacting said well; a metal contact on said principal surface of said bulk material; and a conductive region extending through said bulk material between said metal contact and said first conductive sub-surface layer, wherein the conductive region applies a bias potential to said well via said first conductive sub-surface layer.
Claim 2
Dependent Claim
118 words
An MOS device comprising: a bulk material of a first conductivity having a principal surface; a well of a second conductivity formed in said principal surface of said bulk material; source and drain regions of the first conductivity formed in said well to define a channel region therebetween; a first conductive sub-surface layer of the second conductivity spaced from and beneath said surface of said bulk material and contacting said well; a metal contact on said principal surface of said bulk material; and a conductive region extending through said bulk material between said metal contact and said first conductive sub-surface layer, wherein the conductive region applies a bias potential to said well via said first conductive sub-surface layer.
Claim 3
Dependent Claim
58 words
An MOS device as claimed in claim 1 , further comprising: second source and drain regions of the second conductivity formed in the bulk material to define a second channel region therebetween; and, a second metallic contact on said surface of said bulk material, said second metal contact for applying a second bias potential to said bulk material.
Claim 4
Dependent Claim
102 words
An MOS device as claimed in claim 1 , further comprising: second source and drain regions of the second conductivity formed in the bulk material to define a second channel region therebetween; and a second conductive sub-surface layer of the first conductivity located below said first conductive sub-surface layer such that said first conductive sub-surface layer is located between said second conductive sub-surface layer and said surface of said bulk material; wherein said first conductive sub-surface layer has at least one gap defined therein and said second conductive sub-surface layer is shorted to said bulk material through said at least one gap.
Claim 5
Dependent Claim
42 words
An MOS device as claimed in claim 3 , further comprising a second metallic contact connected to said second conductive sub-surface layer, said second metal contact for applying a second bias potential to said bulk material via said second conductive sub-surface layer.
Claim 6
Dependent Claim
26 words
An MOS device as claimed in claim 4 , wherein said second metal contact is a metal back plate shorted to said second conductive sub-surface layer.
Claim 7
Dependent Claim
49 words
An MOS device as claimed in claim 3 , further comprising a second metallic contact on said surface of said bulk material, said second metal contact for applying a second bias potential to said second conductive sub-surface layer via said bulk material and through said at least one gap.
Claim 8
Dependent Claim
24 words
An MOS device as claimed in claim 1 , wherein said conductive sub-surface layer is an implanted buried layer contained within said bulk material.
Claim 9
Dependent Claim
23 words
An MOS device as claimed in claim 1 , wherein said bulk material is an epitaxial layer grown on said conductive sub-surface layer.
Claim 10
Dependent Claim
129 words
An MOS device comprising: a bulk material of a first conductivity having a principal surface; a plurality of wells of a second conductivity formed in said principal surface of said bulk material; a plurality of source and drain regions of the first conductivity formed in each of said plurality of wells to define respective channel regions therebetween; a first conductive sub-surface layer of the second conductivity spaced from and beneath said surface bulk material and contacting said plurality of wells; a metal contact on said principal surface of said bulk material; and a conductive region extending through said bulk material between said metal contact and said first conductive sub-surface layer, wherein the conductive region applies a bias potential to said plurality of wells via said first conductive sub-surface layer.
Claim 11
Dependent Claim
129 words
An MOS device comprising: a bulk material of a first conductivity having a principal surface; a plurality of wells of a second conductivity formed in said principal surface of said bulk material; a plurality of source and drain regions of the first conductivity formed in each of said plurality of wells to define respective channel regions therebetween; a first conductive sub-surface layer of the second conductivity spaced from and beneath said surface bulk material and contacting said plurality of wells; a metal contact on said principal surface of said bulk material; and a conductive region extending through said bulk material between said metal contact and said first conductive sub-surface layer, wherein the conductive region applies a bias potential to said plurality of wells via said first conductive sub-surface layer.
Claim 12
Dependent Claim
58 words
An MOS device as claimed in claim 9 , further comprising: second source and drain regions of the second conductivity formed in the bulk material to define a second channel region therebetween; and, a second metallic contact on said surface of said bulk material, said second metal contact for applying a second bias potential to said bulk material.
Claim 13
Dependent Claim
102 words
An MOS device as claimed in claim 9 , further comprising: second source and drain regions of the second conductivity formed in the bulk material to define a second channel region therebetween; and a second conductive sub-surface layer of the first conductivity located below said first conductive sub-surface layer such that said first conductive subsurface layer is located between said second conductive sub-surface layer and said surface of said bulk material; wherein said first conductive sub-surface layer has at least one gap defined therein and said second conductive sub-surface layer is shorted to said bulk material through said at least one gap.
Claim 14
Dependent Claim
42 words
An MOS device as claimed in claim 11 , further comprising a second metallic contact connected to said second conductive sub-surface layer, said second metal contact for applying a second bias potential to said bulk material via said second conductive sub-surface layer.
Claim 15
Dependent Claim
26 words
An MOS device as claimed in claim 12 , wherein said second metal contact is a metal back plate shorted to said second conductive sub-surface layer.
Claim 16
Dependent Claim
49 words
An MOS device as claimed in claim 11 , further comprising a second metallic contact on said surface of said bulk material, said second metal contact for applying a second bias potential to said second conductive sub-surface layer via said bulk material and through said at least one gap.
Claim 17
Dependent Claim
24 words
An MOS device as claimed in claim 9 , wherein said conductive sub-surface layer is an implanted buried layer contained within said bulk material.
Claim 18
Dependent Claim
23 words
An MOS device as claimed in claim 9 , wherein said bulk material is an epitaxial layer grown on said conductive sub-surface layer.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2004-04-16 | 2004-10-16 | 2005-04-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2008-04-16 | 2008-10-16 | 2009-04-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2012-04-16 | 2012-10-16 | 2013-04-17 | $7700.00 | Window Closed / Lapsed |