US5262672A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for improvement of interconnection capacitance
Assignee: Nouryon Surface Chemistry AB
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Filing: 1991-11-27
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Granted: 1993-11-16
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Expires: 2011-11-27
Abstract
Abstract A method and apparatus for reducing interconnection capacitance. A lightly doped buried layer is provided in or on a substrate below a field oxide region. The capacitance of an interconnect on the field oxide is significantly reduced by the lightly doped buried layer. When using a p-type substrate, the lightly doped buried layer may, for example, be a lightly doped (10 13 /cm 3 ) n-type region. Junction capacitance of, for example, a bipolar transistor is also reduced.
Inventors
- 👤 Ali A. Iranmanesh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 00:13
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/40; H10W20/495
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
156 words
A semiconductor structure comprising: a) a semiconductor substrate having a first conductivity type, said substrate having a major surface; b) a lightly doped region extending along said major surface, said lightly doped region having a net dopant concentration of less than about 10 14 /cm 3 ; c) a bipolar transistor at a first location along said major surface above said lightly doped region, said bipolar transistor having a collector region, said collector region further comprising a buried layer of opposite conductivity type, said buried layer having a dopant concentration higher than said lightly doped region and extending partially through said lightly doped region, said lightly doped region extending beneath said buried layer; d) a second device at a second location along said major surface; e) a field oxide region between said second device and a third location on said major surface; and f) a conductive interconnect region connecting said second device and said third location.
Claim 2
Dependent Claim
156 words
A semiconductor structure comprising: a) a semiconductor substrate having a first conductivity type, said substrate having a major surface; b) a lightly doped region extending along said major surface, said lightly doped region having a net dopant concentration of less than about 10 14 /cm 3 ; c) a bipolar transistor at a first location along said major surface above said lightly doped region, said bipolar transistor having a collector region, said collector region further comprising a buried layer of opposite conductivity type, said buried layer having a dopant concentration higher than said lightly doped region and extending partially through said lightly doped region, said lightly doped region extending beneath said buried layer; d) a second device at a second location along said major surface; e) a field oxide region between said second device and a third location on said major surface; and f) a conductive interconnect region connecting said second device and said third location.
Claim 3
Dependent Claim
23 words
A structure as recited in claim 1 wherein said interconnect region connects said second device to a bonding pad at said third location.
Claim 4
Dependent Claim
18 words
A structure as recited in claim 1 wherein said lightly doped region is of said opposite conductivity type.
Claim 5
Dependent Claim
121 words
A semiconductor structure comprising: a) a substrate of a first conductivity type and having a major surface; b) a bipolar transistor formed on said major surface, said bipolar transistor comprising an emitter region, a collector region, and a base region between said emitter region and said collector region, said collector region further comprising a buried layer of a second conductivity type; c) means for reducing a parasitic capacitance between said buried layer and said substrate, comprising an intermediate region extending between said buried layer and said substrate, said intermediate region having a net dopant concentration substantially less than said buried layer and said substrate, said intermediate region having a net dopant concentration of less than about 10 14 /cm 3 .
Claim 6
Dependent Claim
121 words
A semiconductor structure comprising: a) a substrate of a first conductivity type and having a major surface; b) a bipolar transistor formed on said major surface, said bipolar transistor comprising an emitter region, a collector region, and a base region between said emitter region and said collector region, said collector region further comprising a buried layer of a second conductivity type; c) means for reducing a parasitic capacitance between said buried layer and said substrate, comprising an intermediate region extending between said buried layer and said substrate, said intermediate region having a net dopant concentration substantially less than said buried layer and said substrate, said intermediate region having a net dopant concentration of less than about 10 14 /cm 3 .
Claim 7
Dependent Claim
17 words
The device as recited in claim 4 wherein said intermediate region is of said second conductivity type.
Claim 8
Dependent Claim
17 words
The device as recited in claim 4 wherein said intermediate region is of said first conductivity type.
Claim 9
Dependent Claim
26 words
The device as recited in claim 4 wherein said intermediate region has a dopant concentration of between about 10 12 and 10 14 /cm 3 .
Claim 10
Dependent Claim
22 words
The device as recited in claim 4 wherein said intermediate region has a dopant concentration of about 10 12 /cm 3 .
Claim 11
Dependent Claim
27 words
The device as recited in claim 4 wherein the intermediate region has a dopant concentration between about two and four orders of magnitude less than said substrate.
Claim 12
Dependent Claim
16 words
The device as recited in claim 9 wherein the intermediate region has said second conductivity type.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-11-15 | 1997-05-17 | 1997-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-11-15 | 2001-05-17 | 2001-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-11-15 | 2005-05-17 | 2005-11-16 | $7700.00 | Window Closed / Lapsed |