US6492241B1
Expired / Lapsed
US
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Integrated capacitors fabricated with conductive metal oxides
Assignee: Micron Technology Inc
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Filing: 2000-04-10
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Granted: 2002-12-10
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Expires: 2020-04-10
Abstract
Abstract A capacitor for a memory device is formed with a conductive oxide for a bottom electrode. The conductive oxide (RuO x ) is deposited under low temperatures as an amorphous film. As a result, the film is conformally deposited over a three dimensional, folding structure. Furthermore, a subsequent polishing step is easily performed on the amorphous film, increasing wafer throughput. After deposition and polishing, the film is crystallized in a non-oxidizing ambient.
Inventors
- 👤 Howard E. Rhodes
- 👤 Mark Visokay
- 👤 Tom Graettinger
- 👤 Dan Gealy
- 👤 Gurtej Sandhu
- 👤 Cem Basceri
- 👤 Steve Cummings
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 01:25
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/60; H10D1/68; H10D1/692; C; C23; C23C; C23C16/00; C23C16/22; C23C16/30; C23C16/40; H10D1/682; H10D1/711; H10D1/716
Claims Analysis
Total Claims: 34
Claim 1
Independent Claim
82 words
A method of forming a container capacitor in an integrated circuit having a bottom electrode plate and a top electrode plate, comprising: depositing an amorphous conductive oxide layer; patterning said amorphous conductive oxide layer to form a plurality of bottom electrode plates across the integrated circuit; crystallizing said bottom electrode plates by annealing said patterned amorphous conductive oxide layer; forming a capacitor dielectric layer in direct contact with said bottom electrode plates; and forming a top electrode plate over said dielectric layer.
Claim 2
Independent Claim
82 words
A method of forming a container capacitor in an integrated circuit having a bottom electrode plate and a top electrode plate, comprising: depositing an amorphous conductive oxide layer; patterning said amorphous conductive oxide layer to form a plurality of bottom electrode plates across the integrated circuit; crystallizing said bottom electrode plates by annealing said patterned amorphous conductive oxide layer; forming a capacitor dielectric layer in direct contact with said bottom electrode plates; and forming a top electrode plate over said dielectric layer.
Claim 3
Dependent Claim
15 words
The method of claim 1 , wherein said conductive oxide layer comprises a metal oxide.
Claim 4
Dependent Claim
14 words
The method of claim 2 , wherein said conductive oxide layer comprises ruthenium oxide.
Claim 5
Dependent Claim
22 words
The method of claim 3 , wherein crystallizing said first electrode plates comprises annealing said conductive oxide layer in a non-oxidizing ambient.
Claim 6
Dependent Claim
15 words
The method of claim 4 , wherein said non-oxidizing ambient comprises a nitrogen source gas.
Claim 7
Dependent Claim
13 words
The method of claim 5 , wherein said nitrogen source gas comprises ammonia.
Claim 8
Dependent Claim
14 words
The method of claim 4 , wherein said non-oxidizing ambient comprises an inert gas.
Claim 9
Dependent Claim
23 words
The method of claim 4 , wherein annealing comprises heating said conductive oxide to a temperature between about 400° C. and 900° C.
Claim 10
Dependent Claim
23 words
The method of claim 8 , wherein annealing comprises heating said conductive oxide to a temperature between about 500° C. and 850° C.
Claim 11
Dependent Claim
20 words
The method of claim 1 , wherein said first electrode plates comprise storage electrodes of capacitors in a memory array.
Claim 12
Dependent Claim
19 words
The method of claim 1 , wherein said capacitor dielectric layer has a dielectric constant greater than about 9.
Claim 13
Dependent Claim
38 words
The method of claim 11 , wherein said capacitor dielectric layer comprises a material selected from the group consisting of tantalum oxide, aluminum oxide, barium strontium titanate, strontium titanate, strontium bismuth tantalate, zirconium oxide and lead zirconium titanate.
Claim 14
Dependent Claim
19 words
The method of claim 1 , wherein depositing said amorphous conductive oxide layer comprises conformally lining a container shape.
Claim 15
Dependent Claim
17 words
The method of claim 13 , wherein patterning said amorphous conductive oxide layer comprises a polishing process.
Claim 16
Dependent Claim
14 words
The method of claim 14 , wherein said polishing process comprises chemical mechanical polishing.
Claim 17
Dependent Claim
20 words
The method of claim 15 , further comprising coating the conductive oxide layer with resist prior to chemical mechanical polishing.
Claim 18
Dependent Claim
19 words
The method of claim 15 , further comprising filling the container shape with spin-on-glass prior to chemical mechanical polishing.
Claim 19
Independent Claim
86 words
A method of forming a memory cell in an integrated circuit, comprising: forming a container in a structural layer; depositing an amorphous conductive oxide layer over the structural layer and into the container; polishing the amorphous conductive oxide layer from over the structural layer, leaving an isolated amorphous conductive oxide layer within the container; crystallizing the isolated amorphous conductive oxide layer to form a bottom electrode; forming a capacitor dielectric directly over the bottom electrode; and depositing a second conductive layer directly over the capacitor dielectric.
Claim 20
Independent Claim
86 words
A method of forming a memory cell in an integrated circuit, comprising: forming a container in a structural layer; depositing an amorphous conductive oxide layer over the structural layer and into the container; polishing the amorphous conductive oxide layer from over the structural layer, leaving an isolated amorphous conductive oxide layer within the container; crystallizing the isolated amorphous conductive oxide layer to form a bottom electrode; forming a capacitor dielectric directly over the bottom electrode; and depositing a second conductive layer directly over the capacitor dielectric.
Claim 21
Dependent Claim
14 words
The method of claim 18 , wherein said conductive oxide layer comprises ruthenium oxide.
Claim 22
Dependent Claim
20 words
The method of claim 18 , wherein crystallizing comprises annealing the isolated amorphous conductive oxide layer in a non-oxidizing ambient.
Claim 23
Dependent Claim
24 words
The method of claim 20 , wherein crystallizing comprises annealing the isolated amorphous conductive oxide layer at between about 500° C. and 850° C.
Claim 24
Dependent Claim
24 words
The method of claim 21 , wherein crystallizing comprises annealing the isolated amorphous conductive oxide layer at between about 700° C. and 800° C.
Claim 25
Dependent Claim
19 words
The method of claim 18 , wherein depositing said second conductive layer comprises depositing a conductive metal oxide layer.
Claim 26
Dependent Claim
38 words
The method of claim 18 , wherein depositing said second conductive layer comprises depositing a material selected from the group consisting of titanium nitride, tantalum nitride, tungsten nitride, lead, doped polysilicon, iridium, rhodium, ruthenium, platinum and alloys thereof.
Claim 27
Dependent Claim
20 words
The method of claim 18 , wherein said second conductive layer comprises a stack of metal nitride and doped polysilicon.
Claim 28
Dependent Claim
35 words
The method of claim 18 , wherein said capacitor dielectric is selected from the group consisting of tantalum oxide, aluminum oxide, barium strontium titanate, strontium titanate, strontium bismuth tantalate, zirconium oxide and lead zirconium titanate.
Claim 29
Dependent Claim
18 words
The method of claim 18 , wherein said capacitor dielectric has a dielectric constant greater than about 9.
Claim 30
Dependent Claim
13 words
The method of claim 18 , wherein said container overlies a polysilicon plug.
Claim 31
Dependent Claim
19 words
The method of claim 18 , wherein depositing the amorphous ruthenium oxide layer comprises lining a three-dimensional folding structure.
Claim 32
Dependent Claim
14 words
The method of claim 29 , wherein the three-dimensional folding structure comprises a container.
Claim 33
Dependent Claim
20 words
The method of claim 30 , wherein the container comprises a void in a structural layer above a semiconductor substrate.
Claim 34
Dependent Claim
25 words
The method of claim 29 , wherein depositing the amorphous ruthenium oxide layer comprises maintaining a workpiece temperature between about 150° C. and 250° C.
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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) | 2005-12-09 | 2006-06-10 | 2006-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2009-12-09 | 2010-06-10 | 2010-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2013-12-09 | 2014-06-10 | 2014-12-10 | $7700.00 | Window Closed / Lapsed |