US4169337A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for polishing semi-conductor materials
Assignee: Rodel Inc
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Filing: 1978-03-30
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Granted: 1979-10-02
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Expires: 1998-03-30
Abstract
Abstract Semi-conductors can be polished with greater efficiency by using as a polishing agent a blend of colloidal silica or silica gel and a water-soluble amine.
Inventors
- 👤 Charles C. Payne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 06:27
CPC Classifications
C; C09; C09G; C09G1/00; C09G1/02; H; H10; H10P; H10P52/00; H10P52/40; H10P52/402
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
48 words
An improved method for polishing silicon wafers and like materials which comprises polishing them with a polishing agent which comprises an aqueous colloidal silica sol or a gel which is combined with 0.1%-5% by weight of a water-soluble amine based on the SiO 2 content of the sol.
Claim 2
Dependent Claim
48 words
An improved method for polishing silicon wafers and like materials which comprises polishing them with a polishing agent which comprises an aqueous colloidal silica sol or a gel which is combined with 0.1%-5% by weight of a water-soluble amine based on the SiO 2 content of the sol.
Claim 3
Dependent Claim
37 words
The method of claim 1 where the polishing agent contains a silica sol having an average particle size diameter within the range of 4-100 millimicrons and the amine contains a primary amino group and 2-8 carbon atoms.
Claim 4
Dependent Claim
10 words
The method of claim 2 wherein the amine is aminoethylethanolamine.
Claim 5
Dependent Claim
39 words
The method of claim 1 where the polishing agent contains a silica sol having an average particle size diameter within the range of 4-100 millimicrons and the amine contains two or more primary amino groups and 2-12 carbon atoms.
Claim 6
Dependent Claim
10 words
The method of claim 4 wherein the amine is ethylenediamine.
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) | 1982-10-01 | 1983-04-02 | 1983-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-10-01 | 1987-04-02 | 1987-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-10-01 | 1991-04-02 | 1991-10-02 | $7700.00 | Window Closed / Lapsed |