Patent EP0103085A1 successfully refreshed from Google Patents.
EP0103085A1
Expired / Lapsed
EP
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A method for polishing semiconductor wafers with montmorillonite slurry
Assignee: International Business Machines Corp
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Filing: 1983-06-23
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Granted: —
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Expires: 2003-06-23
Abstract
Abstract Semiconductor wafers are polished with an abrasive slurry which is prepared by dispersing montmorillonite clay in deionized water. The pH of the slurry is adjusted to 9.5. to 12.5 by adding alkali such a NaOH or KOH. An oxidizing agent need not be included in the slurry.
Inventors
- 👤 Jagtar Singh Basi
- 👤 Eric Mendel
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 16:18
CPC Classifications
H; H10; H10P; H10P52/00; H10P52/40; H10P52/402
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
35 words
A method for polishing a semiconductor wafer comprising: preparing a polishing slurry by dispersing an abrasive powder in water, and polishing the wafer with said slurry, characterized by: selecting montmorillonite clay as the abrasive powder.
Claim 2
Independent Claim
35 words
A method for polishing a semiconductor wafer comprising: preparing a polishing slurry by dispersing an abrasive powder in water, and polishing the wafer with said slurry, characterized by: selecting montmorillonite clay as the abrasive powder.
Claim 3
Dependent Claim
27 words
The method of claim 1 wherein alkali is included in the slurry such that the pH of the slurry is in the range of 9.5 to 12.5.
Claim 4
Dependent Claim
38 words
The method of claim 2 comprising: adding montmorillonite powder to deionized water with continuous stirring to form a colloidal suspension, and adding alkali solution to said suspension to adjust the pH in the range of 9.5 to 12.5.
Claim 5
Dependent Claim
21 words
The method of claim 3 wherein 2 tot 10 percent by weight of montmorillonite powder is added to said deionized water.
Claim 6
Dependent Claim
16 words
The method of claim 2, 3 or 4 wherein said alkali is sodium or potassium hydroxide.
Claim 7
Independent Claim
25 words
The method of any previous claim wherein polishing is done under a low pressure of less than 69 kPa (10 psi) applied to said wafer.
Claim 8
Independent Claim
28 words
The method of any of claims 1-5 wherein polishing is done under a high pressure of 207 to 552 kPa (30 to 80 psi) applied to said wafer.
Claim 9
Independent Claim
24 words
The method of any previous claim wherein sodium hypochlorite is added to the slurry at a time near the end of the polishing cycle.
Claim 10
Dependent Claim
35 words
A composition for polishing semiconductor substrates comprising 2 to 10 percent by weight of montmorillonite clay added to deionized water, and alkali sufficient to render a pH value in the range of 9.5 to 12.5.
Claim 11
Dependent Claim
35 words
A composition for polishing semiconductor substrates comprising 2 to 10 percent by weight of montmorillonite clay added to deionized water, and alkali sufficient to render a pH value in the range of 9.5 to 12.5.
Claim 12
Dependent Claim
13 words
The composition of claim 9 wherein said alkali is sodium or potassium hydroxide.
References Cited (Backward Citations)
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