US4638400A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Refractory metal capacitor structures, particularly for analog integrated circuit devices
Assignee: Intersil Corp
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Filing: 1985-10-24
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Granted: 1987-01-20
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Expires: 2005-10-24
Abstract
Abstract A capacitor structure which is particularly suitable for use in analog integrated circuit devices employs an intermediate layer of a refractory metal disposed in a thin layer overlying a flat dielectric surface. The thinness and the low reflectivity of the refractory metal facilitates precise patterning of the upper plate of the capacitor structure. In the present invention, capacitance is no longer determined by imprecise cuts through thick oxide layers or by patterning of thick metallization layers within these apertures. The use of refractory metals in the capacitor structure also readily permits the incorporation of resistive circuit elements.
Inventors
- 👤 Dale M. Brown
- 👤 Manjin J. Kim
- 👤 Richard D. Baertsch
- 👤 Thomas L. Vogelsong
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 18:37
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/60; H10D1/68
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
116 words
A capacitor structure, for use in integrated circuit devices, said capacitor structure comprising: a substrate having an insulative layer disposed thereon; a first layer of conductive material disposed on said insulative layer on said substrate; a dielectric layer deposited over said first conductive layer; a layer of metal disposed on said dielectric layer, said layer of metal comprising a refractory metal; an insulative layer disposed over said refractory metal layer, said insulative layer having an aperture therein adjacent to at least a portion of said refractory metal layer; and an interconnection metal layer disposed on said insulative layer and extending through said aperture in said insulative layer so as to make contact with said refractory metal.
Claim 2
Dependent Claim
116 words
A capacitor structure, for use in integrated circuit devices, said capacitor structure comprising: a substrate having an insulative layer disposed thereon; a first layer of conductive material disposed on said insulative layer on said substrate; a dielectric layer deposited over said first conductive layer; a layer of metal disposed on said dielectric layer, said layer of metal comprising a refractory metal; an insulative layer disposed over said refractory metal layer, said insulative layer having an aperture therein adjacent to at least a portion of said refractory metal layer; and an interconnection metal layer disposed on said insulative layer and extending through said aperture in said insulative layer so as to make contact with said refractory metal.
Claim 3
Dependent Claim
25 words
The capacitor structure of claim 1 in which said dielectric layer has a substantially flat upper surface in the region above said first conductive layer.
Claim 4
Dependent Claim
13 words
The capacitor structure of claim 1 in which said interconnection metal comprises aluminum.
Claim 5
Dependent Claim
27 words
The capacitor structure of claim 1 in which said refractory metal comprises material selected from the group consisting of chromium, titanium, molybdenum, tungsten, nickel, and alloys thereof.
Claim 6
Dependent Claim
18 words
The capacitor structure of claim 1 in which said refractory metal layer is formed by chemical vapor deposition.
Claim 7
Dependent Claim
16 words
The capacitor structure of claim 1 in which said refractory metal layer is formed by sputtering.
Claim 8
Dependent Claim
16 words
The capacitor structure of claim 1 in which said refractory metal layer is formed by evaporation.
Claim 9
Dependent Claim
20 words
The capacitor structure of claim 1 in which said refractory metal layer is less than approximately 3,000 angstroms in thickness.
Claim 10
Dependent Claim
18 words
The capacitor structure of claim 1 in which said first conductive layer is approximately 5,000 angstroms in thickness.
Claim 11
Dependent Claim
27 words
The capacitor structure of claim 1 in which said substrate insulative material comprises material selected from the group consisting of silicon oxide, silicon nitride, and combinations thereof.
Claim 12
Dependent Claim
28 words
The capacitor structure of claim 1 in which said dielectric layer comprises material selected from the group consisting of silicon oxide, silicon nitride, combinations thereof, and layers thereof.
Claim 13
Dependent Claim
26 words
The capacitor structure of claim 1 in which said insulative layer comprises material selected from the group consisting of silicon oxide, silicon nitride, and combinations thereof.
Claim 14
Dependent Claim
25 words
The capacitor structure of claim 1 in which said refractory metal layer is patterned so as to additionally provide at least one resistive circuit element.
Claim 15
Independent Claim
105 words
A method for accurately producing capacitors in integrated circuits, said method comprising the steps of: disposing a first conductive layer on a substrate having an insulative layer disposed thereon; disposing a dielectric layer over said first conductive layer so that said dielectric layer has a substantially flat upper surface in the region above said first conductive layer; disposing a refractory metal layer over said dielectric layer; patterning said refractory metal layer; providing a second insulative layer, said second insulative layer being disposed over said refractory metal layer; and connecting, through an aperture in said second insulative layer, an interconnection conductor to said refractory metal layer.
Claim 16
Independent Claim
105 words
A method for accurately producing capacitors in integrated circuits, said method comprising the steps of: disposing a first conductive layer on a substrate having an insulative layer disposed thereon; disposing a dielectric layer over said first conductive layer so that said dielectric layer has a substantially flat upper surface in the region above said first conductive layer; disposing a refractory metal layer over said dielectric layer; patterning said refractory metal layer; providing a second insulative layer, said second insulative layer being disposed over said refractory metal layer; and connecting, through an aperture in said second insulative layer, an interconnection conductor to said refractory metal layer.
Claim 17
Dependent Claim
14 words
The method of claim 14 in which said refractory metal is disposed by sputtering.
Claim 18
Dependent Claim
16 words
The method of claim 13 in which said refractory metal is disposed by chemical vapor deposition.
Claim 19
Dependent Claim
14 words
The method of claim 13 in which said refractory metal is disposed by evaporation.
Claim 20
Dependent Claim
16 words
The method of claim 13 in which said refractory metal is disposed in a serpentine pattern.
Claim 21
Dependent Claim
27 words
The method of claim 14 in which said refractory metal layer comprises material selected from the group consisting of chromium, titanium, tungsten, molybdenum, nickel, and alloys thereof.
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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) | 1990-01-19 | 1990-07-21 | 1991-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-19 | 1994-07-21 | 1995-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-19 | 1998-07-21 | 1999-01-20 | $7700.00 | Window Closed / Lapsed |