EP0004033B1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Process for equalizing the material removal rate of wafers by polishing
Assignee: Siltronic AG
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Filing: 1979-03-01
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Granted: 1981-01-07
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Expires: 1999-03-01
Abstract
No abstract record available.
Inventors
- 👤 Hans Chem.-Ing.grad. Krämer
- 👤 Helmuth Chem.-Ing.Grad Kirschner
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 18:11
CPC Classifications
B; B24; B24B; B24B37/00; B24B37/04; B24B37/042
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
103 words
Process for evening out the amount of material removed from discs in polishing with polishing machines equipped with a polishing plate (8) covered with a polishing cloth (9), one or more carrier plates (2), on the side of which that faces the polishing plate (8) the discs (1) to be polished are cemented, and also pressure pistons (3) which press the carrier plates (2) against the polishing plate (8) covered with a polishing cloth (9), characterised in that inserts (4) consisting of soft elastic bodies having pressure- equalisation cells are placed between the pressure piston (3) and the back of the carrier plate.
Claim 2
Dependent Claim
103 words
Process for evening out the amount of material removed from discs in polishing with polishing machines equipped with a polishing plate (8) covered with a polishing cloth (9), one or more carrier plates (2), on the side of which that faces the polishing plate (8) the discs (1) to be polished are cemented, and also pressure pistons (3) which press the carrier plates (2) against the polishing plate (8) covered with a polishing cloth (9), characterised in that inserts (4) consisting of soft elastic bodies having pressure- equalisation cells are placed between the pressure piston (3) and the back of the carrier plate.
Claim 3
Dependent Claim
12 words
Process according to claim 1, characterised in that air-cushion films are inserted.
References Cited (Backward Citations)
No citation records indexed.
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