US4117093A
Expired / Lapsed
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Method of making an amorphous silicon dioxide free of metal ions
Assignee: International Business Machines Corp
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Filing: 1977-06-17
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Granted: 1978-09-26
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Expires: 1997-06-17
Abstract
Abstract Amorphous silicon dioxide particles for polishing semiconductor surfaces are prepared by boiling, at reflux, a mixture of surplus organic amine, a hydroxybenzene, water and silicon in the presence of oxygen to precipitate silicon dioxide.
Inventors
- 👤 Friedrich Christian Brunner
- 👤 Friedrich Wilhelm Schwerdt
- 👤 Hans-Heinz Steinbeck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:23
CPC Classifications
H; H10; H10P; H10P52/00; H10P52/40; H10P52/402; C; C09; C09K; C09K3/00; C09K3/14; C09K3/1454; C09K3/1463
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
53 words
A method of making an amorphous silicon dioxide free of metal ions comprising boiling a mixture of a hydroxybenzene, water, high grade silicon and organic amine in molar surplus to the amount of silicon and hydroxybenzene under reflux with bubbling oxygen to precipitate silicon dioxide, and rinsing the precipitated silicon dioxide with water.
Claim 2
Independent Claim
53 words
A method of making an amorphous silicon dioxide free of metal ions comprising boiling a mixture of a hydroxybenzene, water, high grade silicon and organic amine in molar surplus to the amount of silicon and hydroxybenzene under reflux with bubbling oxygen to precipitate silicon dioxide, and rinsing the precipitated silicon dioxide with water.
Claim 3
Dependent Claim
17 words
The method of claim 1 including the steps of rinsing the silicon dioxide with alcohol and drying.
Claim 4
Dependent Claim
35 words
The method of claim 1, in which the silicon is added to the hydroxybenzene-water solution in the form of thin disks, and that prior to being added the silicon is cleaned with diluted hydrofluoric acid.
Claim 5
Dependent Claim
20 words
The method of claim 1 in which the organic amine is ethylene diamine and in which the hydroxybenzene is pyrocatechol.
Claim 6
Dependent Claim
21 words
The method of claim 4 in which the ethylene diamine and pyrocatechol are used in a mole ratio of about 10:1.
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) | 1981-09-25 | 1982-03-27 | 1982-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-09-25 | 1986-03-27 | 1986-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-09-25 | 1990-03-27 | 1990-09-26 | $7700.00 | Window Closed / Lapsed |