US4057939A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silicon wafer polishing
Assignee: International Business Machines Corp
•
Filing: 1975-12-05
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Granted: 1977-11-15
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Expires: 1995-12-05
Abstract
Abstract The polishing of monocrystalline silicon wafers with an aqueous composition of fine sized abrasive particles, a soluble alkali metal base such a sodium carbonate and an oxidizing agent such as sodium or potassium salt of dichloroisocyanuric acid (e.g., salts of halo-trizenetrione).
Inventors
- 👤 Jagtar S. Basi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:27
CPC Classifications
H; H10; H10P; H10P52/00; H10P52/40; H10P52/402; C; C09; C09G; C09G1/00; C09G1/02
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
86 words
A reagent composition for polishing substrates comprising an aqueous mixture of silicon dioxide particles in a size range of about 5 to about 200 millimicrons, a soluble alkali metal base and an oxidizing agent selected from the group consisting of sodium and potassium salts of dihaloisocyanuric acid, wherein the ratio of said base to said oxidizing agent is in the range of about 05:1 to about 3.2:1, and with the ratio of silicon particles to said base in the range of about 8.5:1 to about 55.6:1.
Claim 2
Dependent Claim
86 words
A reagent composition for polishing substrates comprising an aqueous mixture of silicon dioxide particles in a size range of about 5 to about 200 millimicrons, a soluble alkali metal base and an oxidizing agent selected from the group consisting of sodium and potassium salts of dihaloisocyanuric acid, wherein the ratio of said base to said oxidizing agent is in the range of about 05:1 to about 3.2:1, and with the ratio of silicon particles to said base in the range of about 8.5:1 to about 55.6:1.
Claim 3
Dependent Claim
13 words
The composition of claim 1 wherein said base is an alkali metal carbonate.
Claim 4
Dependent Claim
31 words
The composition of claim 2 wherein said carbonate is a sodium salt thereof and said oxidizing agent is selected from the group consisting of potassium and sodium salts of dichloroisocyanuric acid.
Claim 5
Dependent Claim
23 words
The composition of claim 3 wherein the ratio of said carbonate to said oxidizing agent is in the range of 0.5:1 to 3.2:1.
Claim 6
Dependent Claim
20 words
The composition of claim 1 wherein said particles are selected from the group consisting of silica sols and silica gels.
Claim 7
Dependent Claim
20 words
The composition of claim 2 wherein said particles are selected from the group consisting of silica sols and silica gels.
Claim 8
Dependent Claim
20 words
The composition of claim 3 wherein said particles are selected from the group consisting of silica sols and silica gels.
Claim 9
Dependent Claim
20 words
The composition of claim 4 wherein said particles are selected from the group consisting of silica sols and silica gels.
Claim 10
Dependent Claim
26 words
A process for polishing crystalline silicon which comprises applying to a surface of said silicon a polishing composition of claim 1, and polishing said silicon therewith.
Claim 11
Dependent Claim
26 words
A process for polishing crystalline silicon which comprises applying to a surface of said silicon a polishing composition of claim 2, and polishing said silicon therewith.
Claim 12
Dependent Claim
26 words
A process for polishing crystalline silicon which comprises applying to a surface of said silicon a polishing composition of claim 3, and polishing said silicon therewith.
Claim 13
Dependent Claim
26 words
A process for polishing crystalline silicon which comprises applying to a surface of said silicon a polishing composition of claim 4, and polishing said silicon therewith.
Claim 14
Dependent Claim
26 words
A process for polishing crystalline silicon which comprises applying to a surface of said silicon a polishing composition of claim 5, and polishing said silicon therewith.
Claim 15
Dependent Claim
26 words
A process for polishing crystalline silicon which comprises applying to a surface of said silicon a polishing composition of claim 6, and polishing said silicon therewith.
Claim 16
Dependent Claim
26 words
A process for polishing crystalline silicon which comprises applying to a surface of said silicon a polishing composition of claim 7, and polishing said silicon therewith.
Claim 17
Dependent Claim
26 words
A process for polishing crystalline silicon which comprises applying to a surface of said silicon a polishing composition of claim 8, and polishing said silicon therewith.
References Cited (Backward Citations)
US3328141A
Cited
US3552071A
Cited
US3715842A
Cited
US3807979A
Cited
US3874129A
Cited
US3922393A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-11-14 | 1981-05-16 | 1981-11-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-11-14 | 1985-05-16 | 1985-11-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-11-14 | 1989-05-16 | 1989-11-15 | $7700.00 | Window Closed / Lapsed |