Patent US6487390B1 successfully refreshed from Google Patents.
Patent US4954141A successfully refreshed from Google Patents.
US4954141A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polishing pad for semiconductor wafers
Assignee: Resonac Holdings Corp
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Filing: 1989-01-25
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Granted: 1990-09-04
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Expires: 2009-01-25
Abstract
Abstract A polishing pad for a semiconductor wafer, which pad is made of a foamed fluorine-contained resin sheet and is highly resistant to a corrosive polishing solution such as bromine-methanol system or bromine-methanol-silica powder system.
Inventors
- 👤 Masahiro Takiyama
- 👤 Kunihiro Miyazaki
- 👤 Kenichiro Shiozawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:30
CPC Classifications
B; B24; B24B; B24B37/00; B24B37/11; B24B37/20; B24B37/24; B24D; B24D3/00; B24D3/02; B24D3/20; B24D3/28; B24D3/32; Y; Y10; Y10S; Y10S451/00; Y10S451/921
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
45 words
A polishing pad for obtaining a mirror-like surface of a semiconductor wafer, said pad comprising a sheet of foamed fluorine-containing resin, wherein said pad of said foamed fluorine-containing resin has an average pore size of 10 to 2000 μm and porosity of 60 to 95%.
Claim 2
Dependent Claim
45 words
A polishing pad for obtaining a mirror-like surface of a semiconductor wafer, said pad comprising a sheet of foamed fluorine-containing resin, wherein said pad of said foamed fluorine-containing resin has an average pore size of 10 to 2000 μm and porosity of 60 to 95%.
Claim 3
Dependent Claim
28 words
A pad according to claim 1, wherein said fluorine-containing resin is selected from the group consisting of tetrafluoroethylene-based resin, trifluorochloroethylene-based resin, vinylidene fluoride-based resin, and vinyl fluoride-based resin.
Claim 4
Dependent Claim
18 words
A pad according to claim 1, wherein said average pore size is from 50 μm to 500 μm.
Claim 5
Dependent Claim
26 words
A pad according to claim 1, wherein an average thickness of a cell wall of said foamed fluorine-containing resin is from 0.2 μm to 100 μm.
Claim 6
Dependent Claim
21 words
A pad according to claim 4, wherein said average thickness of a cell wall is from 0.5 μm to 50 μm.
Claim 7
Dependent Claim
30 words
A pad according to claim 1, wherein said foamed fluorine-containing resin sheet is adhered to a polishing plate and an exposed surface of the foamed fluorine-containing resin sheet is trued.
References Cited (Backward Citations)
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GB902716A
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FR2063961A1
Cited
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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) | 1993-09-03 | 1994-03-05 | 1994-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-09-03 | 1998-03-05 | 1998-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-09-03 | 2002-03-05 | 2002-09-04 | $7700.00 | Window Closed / Lapsed |