US5516346A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Slurries for chemical mechanical polishing
Assignee: Intel Corp
•
Filing: 1994-05-13
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Granted: 1996-05-14
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Expires: 2014-05-13
Abstract
Abstract Novel slurries for the chemical mechanical polishing of thin films used in integrated circuit manufacturing. A tungsten slurry of the present invention comprises an oxidizing agent, such as potassium ferricyanide, an abrasive such as silica, and has a pH between two and four. The tungsten slurry of the present invention can be used in a chemical mechanical planarization process to polish back a blanket deposited tungsten film to form plugs or vias. The tungsten slurry can also be used to polish copper, tungsten silicide, and titanium nitride. A second slurry, which is a 9:1 dilution of the tungsten slurry is ideal for chemical mechanical polishing of titanium nitride films. A third slurry of the present invention comprises a fluoride salt, an abrasive such as silica and has a pH≦8. The third slurry can be used to polish titanium films.
Inventors
- 👤 Kenneth C. Cadien
- 👤 Daniel A. Feller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:08
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/032; H10W20/033; C; C09; C09G; C09G1/00; C09G1/02; C09K; C09K3/00; C09K3/14; C09K3/1454; C09K3/1463; H10P; H10P52/00; H10P52/40; H10P52/403; H10W20/062
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
36 words
A slurry for chemical mechanically polishing a titanium film, said slurry comprising: a fluoride salt in a concentration sufficient to complex said titanium film; an abrasive; and wherein said slurry has a pH less than eight.
Claim 2
Dependent Claim
36 words
A slurry for chemical mechanically polishing a titanium film, said slurry comprising: a fluoride salt in a concentration sufficient to complex said titanium film; an abrasive; and wherein said slurry has a pH less than eight.
Claim 3
Dependent Claim
12 words
The slurry of claim 1 wherein said fluoride salt is potassium fluoride.
Claim 4
Dependent Claim
14 words
The slurry of claim 2 wherein said slurry comprises approximately 0.5 molar potassium fluoride.
Claim 5
Dependent Claim
10 words
The slurry of claim 1 wherein said abrasive is silica.
Claim 6
Dependent Claim
11 words
The slurry of claim 4 wherein said pH is approximately 5.2.
Claim 7
Dependent Claim
11 words
The slurry of claim 1 wherein said pH is approximately 5.2.
Claim 8
Dependent Claim
17 words
The slurry of claim 1 further comprising acetic acid in a concentration sufficient to maintain said pH.
Claim 9
Dependent Claim
15 words
The slurry of claim 1 wherein said slurry comprises less than 15% silica by weight.
Claim 10
Dependent Claim
14 words
The slurry of claim 8 wherein said slurry comprises approximately 0.5% silica by weight.
Claim 11
Dependent Claim
34 words
A slurry for chemical mechanical polishing a titanium film, said slurry comprising: potassium fluoride, in an amount sufficient to complex said titanium film; silica; and wherein said slurry has a pH less than eight.
Claim 12
Dependent Claim
34 words
A slurry for chemical mechanical polishing a titanium film, said slurry comprising: potassium fluoride, in an amount sufficient to complex said titanium film; silica; and wherein said slurry has a pH less than eight.
Claim 13
Dependent Claim
14 words
The slurry of claim 10 wherein said slurry comprises approximately 0.5 molar potassium fluoride.
Claim 14
Dependent Claim
14 words
The slurry of claim 10 wherein said slurry comprises approximately 0.5% silica by weight.
Claim 15
Dependent Claim
20 words
The slurry of claim 10 wherein said slurry further comprises acetic acid in a concentration sufficient to maintain said pH.
Claim 16
Dependent Claim
32 words
A slurry for chemical mechanical polishing a titanium film, said slurry comprising: approximately 0.5 molar potassium fluoride; approximately 0.5% silica by weight; and wherein said slurry has a pH of approximately 5.2.
Claim 17
Dependent Claim
32 words
A slurry for chemical mechanical polishing a titanium film, said slurry comprising: approximately 0.5 molar potassium fluoride; approximately 0.5% silica by weight; and wherein said slurry has a pH of approximately 5.2.
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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) | 1999-05-14 | 1999-11-13 | 2000-05-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-05-14 | 2003-11-13 | 2004-05-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-05-14 | 2007-11-13 | 2008-05-14 | $7700.00 | Window Closed / Lapsed |