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US4704625A Expired / Lapsed US ⏱️ 0.0 years remaining

Capacitor with reduced voltage variability

Assignee: NXP USA Inc
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Filing: 1982-08-05
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Granted: 1987-11-03
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Expires: 2002-08-05
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Abstract

Abstract An MOS capacitive structure comprising a substrate of a first conductivity type, a first region of the first conductivity type but having a different impurity concentration for contacting the substrate, a second region of opposite conductivity type for contacting the substrate, and a dielectric over a region of the substrate adjacent the first and second regions and having a conductive layer thereon forming one plate of the capacitor while the substrate opposite the conductive layer forms the other plate. The first and second regions are contacted and coupled together in order to provide good electrical contact to the substrate region opposite the conductive layer regardless of whether the substrate under the conductive layer is depleted or inverted.

Inventors

  • 👤 Robert D. Lee

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 07:15
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/60; H10D1/62; H10D1/66

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 140 words
A semiconductor device comprising: a substrate of a first conductivity type and having a first surface, a first region in and adjacent to the surface, of the first conductivity type, and having an impurity concentration higher than that of the substrate, a second region in and adjacent to the surface of opposite conductivity type to the substrate, and spaced apart from the first region, means for contacting the first region and the second region and for coupling the first region and the second region together, a conductive layer opposite a region of the substrate abutting the first region and the second region and insulated from the substrate, and means for contacting the conductive layer thereby forming a capacitor in which one plate is contacted by the first and second regions and a second plate is formed by the conductive layer.
Claim 2
Dependent Claim 140 words
A semiconductor device comprising: a substrate of a first conductivity type and having a first surface, a first region in and adjacent to the surface, of the first conductivity type, and having an impurity concentration higher than that of the substrate, a second region in and adjacent to the surface of opposite conductivity type to the substrate, and spaced apart from the first region, means for contacting the first region and the second region and for coupling the first region and the second region together, a conductive layer opposite a region of the substrate abutting the first region and the second region and insulated from the substrate, and means for contacting the conductive layer thereby forming a capacitor in which one plate is contacted by the first and second regions and a second plate is formed by the conductive layer.
Claim 3
Dependent Claim 28 words
A semiconductor device as set forth in claim 1 wherein the substrate and the first region are of N-type material, and the second region is of P-type material.
Claim 4
Dependent Claim 28 words
A semiconductor device as set forth in claim 1 wherein the substrate and the first region are of P-type material, and the second region is of N-type material.
Claim 5
Dependent Claim 144 words
A semiconductor device comprising: a substrate of a first conductivity type and having a surface, a well of a second conductivity type formed in and adjacent to the surface, a first region in the well, of the second conductivity type, and having an impurity concentration higher than that of the well, a second region in the well, of the first conductivity type, and spaced from the first region, means for contacting the first region and the second region and for coupling the first region and the second region together, a conductive layer opposite a region of the well abutting the first region and the second region, and insulated from the well, and means for contacting the conductive layer, thereby forming a capacitor in which one plate is contacted by the first and second regions and a second plate is formed by the conductive layer.
Claim 6
Dependent Claim 144 words
A semiconductor device comprising: a substrate of a first conductivity type and having a surface, a well of a second conductivity type formed in and adjacent to the surface, a first region in the well, of the second conductivity type, and having an impurity concentration higher than that of the well, a second region in the well, of the first conductivity type, and spaced from the first region, means for contacting the first region and the second region and for coupling the first region and the second region together, a conductive layer opposite a region of the well abutting the first region and the second region, and insulated from the well, and means for contacting the conductive layer, thereby forming a capacitor in which one plate is contacted by the first and second regions and a second plate is formed by the conductive layer.
Claim 7
Dependent Claim 144 words
A semiconductor device comprising: a substrate of a first conductivity type and having a surface, a well of the first conductivity type formed in and adjacent o the surface, a first region in the well, of the first conductivity type, and having an impurity concentration higher than that of the well, a second region in the well, of the second conductivity type, and spaced from the first region, means for contacting the first region and the second region and for coupling the first region and the second region together, a conductive layer opposite a region of the well abutting the first region and the second region, and insulated from the well, and means for contacting the conductive layer, thereby forming a capacitor in which one plate is contacted by the first and second regions and a second plate is formed by the conductive layer.
Claim 8
Dependent Claim 144 words
A semiconductor device comprising: a substrate of a first conductivity type and having a surface, a well of the first conductivity type formed in and adjacent o the surface, a first region in the well, of the first conductivity type, and having an impurity concentration higher than that of the well, a second region in the well, of the second conductivity type, and spaced from the first region, means for contacting the first region and the second region and for coupling the first region and the second region together, a conductive layer opposite a region of the well abutting the first region and the second region, and insulated from the well, and means for contacting the conductive layer, thereby forming a capacitor in which one plate is contacted by the first and second regions and a second plate is formed by the conductive layer.
Claim 9
Dependent Claim 31 words
A semiconductor device as set forth in claim 4 or claim 5 wherein the well and the first region are of N-type material and the second region is of P-type material.
Claim 10
Dependent Claim 31 words
A semiconductor device as set forth in claim 4 or claim 5 wherein the well and the first region are of P-type material and the second region is of N-type material.

References Cited (Backward Citations)

US3535600A Cited
US3562608A Cited
US4255677A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-11-02 1991-05-04 1991-11-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-11-02 1995-05-04 1995-11-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-11-02 1999-05-04 1999-11-03 $7700.00 Window Closed / Lapsed

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