Patent US5735963A successfully refreshed from Google Patents.
US5735963A
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US
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Method of polishing
Assignee: Nokia of America Corp
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Filing: 1996-12-17
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Granted: 1998-04-07
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Expires: 2016-12-17
Abstract
Abstract A method for CMP of, illustratively, tungsten is disclosed. Hydroxylamine or hydroxylamine sulfate are employed to oxidize the metal, while gamma (γ) alumina is employed to abrade the oxidized metal.
Inventors
- 👤 Yaw Samuel Obeng
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 23:14
CPC Classifications
C; C09; C09G; C09G1/00; C09G1/02; H; H10; H10P; H10P52/00; H10P52/40; H10P52/403
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
23 words
A method of polishing a material comprising: exposing said material to a slurry which contains an abrasive and an organic oxidant being hydroxylamine.
Claim 2
Independent Claim
23 words
A method of polishing a material comprising: exposing said material to a slurry which contains an abrasive and an organic oxidant being hydroxylamine.
Claim 3
Dependent Claim
11 words
The method of claim 1 wherein said abrasive is γ alumina.
Claim 4
Dependent Claim
13 words
The method of claim 1 wherein the pH of said slurry is acidic.
Claim 5
Dependent Claim
16 words
The method of claim 3 wherein the pH of said slurry is between 1 and 2.
Claim 6
Dependent Claim
25 words
The method of claim 1 in which said slurry contains 0.1-20% Weight/Volume alumina 0.1-20% Weight/Volume oxidant 0.1-20% Weight/Volume complexing agent and 0.1-20% Weight/Volume non-ionic surfactant.
Claim 7
Independent Claim
35 words
A method of polishing a material comprising: exposing said material to a slurry which contains an abrasive and an organic oxidant, said organic oxidant being chosen from the groups consisting of ##STR2## and hydroxylamine sulfate.
Claim 8
Independent Claim
35 words
A method of polishing a material comprising: exposing said material to a slurry which contains an abrasive and an organic oxidant, said organic oxidant being chosen from the groups consisting of ##STR2## and hydroxylamine sulfate.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-04-06 | 2001-10-06 | 2002-04-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-04-06 | 2005-10-06 | 2006-04-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-04-06 | 2009-10-06 | 2010-04-07 | $7700.00 | Window Closed / Lapsed |