US5555486A
Expired / Lapsed
US
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Hybrid metal/metal oxide electrodes for ferroelectric capacitors
Assignee: North Carolina State University
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Filing: 1994-12-29
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Granted: 1996-09-10
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Expires: 2014-12-29
Abstract
Abstract Ferroelectric capacitors with hybrid electrodes including both a conducting oxide and a noble metal may be used to achieve devices having improved performance over capacitors with either platinum or ruthenium oxide electrodes. These hybrid electrode structures can improve capacitor performance both in terms of fatigue and leakage current. Accordingly, these ferroelectric capacitors with hybrid electrodes can be used as elements of an integrated circuit such as a non-volatile memory or dynamic random access memory.
Inventors
- 👤 Angus I. Kingon
- 👤 Husam N. Al-Shareef
- 👤 Orlando H. Auciello
- 👤 Ken D. Gifford
- 👤 Dan J. Lichtenwalner
- 👤 Rovindra Dat
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:32
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/60; H10D1/68
Claims Analysis
Total Claims: 51
Claim 1
Independent Claim
88 words
A ferroelectric capacitor comprising: a first layer comprising a conducting metal oxide; a second layer on said first layer, said second layer comprising a metal, wherein said second layer is deposited sufficiently thin to complement said first layer to improve the leakage current behavior of the capacitor and minimize polarization fatigue; a third layer on said second layer opposite said first layer, said third layer comprising a ferroelectric material; and a fourth layer on said third layer opposite said second layer, said fourth layer comprising a conductive material.
Claim 2
Dependent Claim
88 words
A ferroelectric capacitor comprising: a first layer comprising a conducting metal oxide; a second layer on said first layer, said second layer comprising a metal, wherein said second layer is deposited sufficiently thin to complement said first layer to improve the leakage current behavior of the capacitor and minimize polarization fatigue; a third layer on said second layer opposite said first layer, said third layer comprising a ferroelectric material; and a fourth layer on said third layer opposite said second layer, said fourth layer comprising a conductive material.
Claim 3
Dependent Claim
31 words
A ferroelectric capacitor according to claim 1 wherein said conductive metal oxide comprises one of ruthenium oxide, iridium oxide, lanthanum strontium cobalt oxide, indium tin oxide, or yttrium barium copper oxide.
Claim 4
Dependent Claim
21 words
A ferroelectric capacitor according to claim 1 wherein said second layer is in the range of 50 to 300 Angstroms thick.
Claim 5
Dependent Claim
14 words
A ferroelectric capacitor according to claim 1 wherein said metal comprises a noble metal.
Claim 6
Dependent Claim
13 words
A ferroelectric capacitor according to claim 4 wherein said noble metal comprises platinum.
Claim 7
Dependent Claim
15 words
A ferroelectric capacitor according to claim 1 wherein said conductive material comprises a conductive oxide.
Claim 8
Dependent Claim
15 words
A ferroelectric capacitor according to claim 1 wherein said ferroelectric material comprises lead zirconate titanate.
Claim 9
Dependent Claim
16 words
A ferroelectric capacitor according to claim 1 wherein said capacitor is included in an integrated circuit.
Claim 10
Dependent Claim
19 words
A ferroelectric capacitor according to claim 1 further comprising a substrate on said first layer opposite said second layer.
Claim 11
Dependent Claim
44 words
A ferroelectric capacitor according to claim 9 wherein said substrate comprises one of a silicon layer, a silicon dioxide layer, a magnesium oxide layer, a sapphire layer, a silicon carbide layer, a gallium arsenide layer, or a silicon dioxide layer on a silicon layer.
Claim 12
Dependent Claim
90 words
A ferroelectric capacitor comprising: a first layer comprising a metal; a second layer on said first layer, said second layer comprising a conductive metal oxide wherein said second layer is in the range of 150 to 200 Angstroms thick, wherein said second layer improves polarization fatigue of the capacitor without compromising leakage current; a third layer on said second layer opposite said first layer, said third layer comprising a ferroelectric material; and a fourth layer on said third layer opposite said second layer, said fourth layer comprising a conductive material.
Claim 13
Dependent Claim
90 words
A ferroelectric capacitor comprising: a first layer comprising a metal; a second layer on said first layer, said second layer comprising a conductive metal oxide wherein said second layer is in the range of 150 to 200 Angstroms thick, wherein said second layer improves polarization fatigue of the capacitor without compromising leakage current; a third layer on said second layer opposite said first layer, said third layer comprising a ferroelectric material; and a fourth layer on said third layer opposite said second layer, said fourth layer comprising a conductive material.
Claim 14
Dependent Claim
31 words
A ferroelectric capacitor according to claim 11 wherein said conductive metal oxide comprises one of ruthenium oxide, iridium oxide, lanthanum strontium cobalt oxide, indium tin oxide, or yttrium barium copper oxide.
Claim 15
Dependent Claim
14 words
A ferroelectric capacitor according to claim 11 wherein said metal comprises a noble metal.
Claim 16
Dependent Claim
13 words
A ferroelectric capacitor according to claim 13 wherein said noble metal comprises platinum.
Claim 17
Dependent Claim
15 words
A ferroelectric capacitor according to claim 11 wherein said conductive material comprises a conductive oxide.
Claim 18
Dependent Claim
15 words
A ferroelectric capacitor according to claim 11 wherein said ferroelectric material comprises lead zirconate titanate.
Claim 19
Dependent Claim
16 words
A ferroelectric capacitor according to claim 11 wherein said capacitor is included in an integrated circuit.
Claim 20
Dependent Claim
19 words
A ferroelectric capacitor according to claim 11 further comprising a substrate on said first layer opposite said second layer.
Claim 21
Dependent Claim
44 words
A ferroelectric capacitor according to claim 18 wherein said substrate comprises one of a silicon layer, a silicon dioxide layer, a magnesium oxide layer, a sapphire layer, a silicon carbide layer, a gallium arsenide layer, or a silicon dioxide layer on a silicon layer.
Claim 22
Dependent Claim
52 words
A ferroelectric capacitor comprising: a first layer comprising a mixture of a conductive metal oxide and a noble metal; a second layer on said first layer, said second layer comprising a ferroelectric material; and a third layer on said second layer opposite said first layer, said third layer comprising a conductive material.
Claim 23
Dependent Claim
52 words
A ferroelectric capacitor comprising: a first layer comprising a mixture of a conductive metal oxide and a noble metal; a second layer on said first layer, said second layer comprising a ferroelectric material; and a third layer on said second layer opposite said first layer, said third layer comprising a conductive material.
Claim 24
Dependent Claim
31 words
A ferroelectric capacitor according to claim 20 wherein said conductive metal oxide comprises one of ruthenium oxide, iridium oxide, lanthanum strontium cobalt oxide, indium tin oxide, or yttrium barium copper oxide.
Claim 25
Dependent Claim
13 words
A ferroelectric capacitor according to claim 20 wherein said noble metal comprises platinum.
Claim 26
Dependent Claim
19 words
A ferroelectric capacitor according to claim 22 wherein said first layer comprises less than about 50 atomic percent platinum.
Claim 27
Dependent Claim
15 words
A ferroelectric capacitor according to claim 20 wherein said conductive material comprises a conductive oxide.
Claim 28
Dependent Claim
15 words
A ferroelectric capacitor according to claim 20 wherein said ferroelectric material comprises lead zirconate titanate.
Claim 29
Dependent Claim
16 words
A ferroelectric capacitor according to claim 20 wherein said capacitor is part of an integrated circuit.
Claim 30
Dependent Claim
19 words
A ferroelectric capacitor according to claim 20 further comprising a substrate on said first layer opposite said second layer.
Claim 31
Dependent Claim
44 words
A ferroelectric capacitor according to claim 27 wherein said substrate comprises one of a silicon layer, a silicon dioxide layer, a magnesium oxide layer, a sapphire layer, a silicon carbide layer, a gallium arsenide layer, or a silicon dioxide layer on a silicon layer.
Claim 32
Dependent Claim
73 words
A ferroelectric capacitor comprising: a first layer comprising a plurality of repeating alternating interlayers, at least one of said alternating interlayers comprising a first metal, and another of said interlayers comprising one of a second metal and a conducting oxide; a second layer on said first layer, said second layer comprising a ferroelectric material; and a third layer on said second layer opposite said first layer, said third layer comprising a conductive material.
Claim 33
Dependent Claim
73 words
A ferroelectric capacitor comprising: a first layer comprising a plurality of repeating alternating interlayers, at least one of said alternating interlayers comprising a first metal, and another of said interlayers comprising one of a second metal and a conducting oxide; a second layer on said first layer, said second layer comprising a ferroelectric material; and a third layer on said second layer opposite said first layer, said third layer comprising a conductive material.
Claim 34
Dependent Claim
45 words
A ferroelectric capacitor according to claim 29 wherein at least one of said alternating interlayers comprises a noble metal, and another of said interlayers comprises one of ruthenium, iridium, ruthenium oxide, iridium oxide, lanthanum strontium cobalt oxide, indium tin oxide, or yttrium barium copper oxide.
Claim 35
Dependent Claim
15 words
A ferroelectric capacitor according to claim 29 wherein said conductive material comprises a conductive oxide.
Claim 36
Dependent Claim
15 words
A ferroelectric capacitor according to claim 29 wherein said ferroelectric material comprises lead zirconate titanate.
Claim 37
Dependent Claim
16 words
A ferroelectric capacitor according to claim 29 wherein said capacitor is included in an integrated circuit.
Claim 38
Dependent Claim
19 words
A ferroelectric capacitor according to claim 29 further comprising a substrate on said first layer opposite said second layer.
Claim 39
Dependent Claim
44 words
A ferroelectric capacitor according to claim 34 wherein said substrate comprises one of a silicon layer, a silicon dioxide layer, a magnesium oxide layer, a sapphire layer, a silicon carbide layer, a gallium arsenide layer, or a silicon dioxide layer on a silicon layer.
Claim 40
Dependent Claim
27 words
A ferroelectric capacitor according to claim 29 further comprising a primary layer on said first layer opposite said second layer, said primary layer comprising a primary metal.
Claim 41
Dependent Claim
15 words
A ferroelectric capacitor according to claim 36 wherein said primary metal comprises a noble metal.
Claim 42
Dependent Claim
13 words
A ferroelectric capacitor according to claim 37 wherein said noble metal comprises platinum.
Claim 43
Dependent Claim
68 words
A ferroelectric capacitor comprising: a first layer comprising a metal; a second layer on said first layer, said second layer comprising a conductive metal oxide; a third layer on said second layer opposite said first layer, said third layer comprising a ferroelectric material; and a fourth layer on and in direct contact with said third layer opposite said second layer, said fourth layer comprising said conductive metal oxide.
Claim 44
Dependent Claim
68 words
A ferroelectric capacitor comprising: a first layer comprising a metal; a second layer on said first layer, said second layer comprising a conductive metal oxide; a third layer on said second layer opposite said first layer, said third layer comprising a ferroelectric material; and a fourth layer on and in direct contact with said third layer opposite said second layer, said fourth layer comprising said conductive metal oxide.
Claim 45
Dependent Claim
31 words
A ferroelectric capacitor according to claim 39 wherein said conductive metal oxide comprises one of ruthenium oxide, iridium oxide, lanthanum strontium cobalt oxide, indium tin oxide, or yttrium barium copper oxide.
Claim 46
Dependent Claim
14 words
A ferroelectric capacitor according to claim 39 wherein said metal comprises a noble metal.
Claim 47
Dependent Claim
13 words
A ferroelectric capacitor according to claim 39 wherein said noble metal comprises platinum.
Claim 48
Dependent Claim
15 words
A ferroelectric capacitor according to claim 39 wherein said ferroelectric material comprises lead zirconate titanate.
Claim 49
Dependent Claim
16 words
A ferroelectric capacitor according to claim 39 wherein said capacitor is included in an integrated circuit.
Claim 50
Dependent Claim
19 words
A ferroelectric capacitor according to claim 39 further comprising a substrate on said first layer opposite said second layer.
Claim 51
Dependent Claim
44 words
A ferroelectric capacitor according to claim 45 wherein said substrate comprises one of a silicon layer, a silicon dioxide layer, a magnesium oxide layer, a sapphire layer, a silicon carbide layer, a gallium arsenide layer, or a silicon dioxide layer on a silicon layer.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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