US5865891A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Planarization process using artificial gravity
Assignee: Vanguard International Semiconductor Corp
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Filing: 1997-11-20
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Granted: 1999-02-02
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Expires: 2017-11-20
Abstract
Abstract The time needed to planarize the surface of an integrated circuit is reduced by causing the planarization liquid to settle in the presence of artificial gravity that supplements natural gravity. A number of different ways to achieve artificial gravity are described. These include centrifuging, magnetic repulsion, vertical pulling by a motor, and providing a pressure differential between the top and bottom sides of the wafer holder.
Inventors
- 👤 Kung Linliu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:48
CPC Classifications
B; B05; B05D; B05D3/00; B05D3/12; B05D1/00; B05D1/002; B24; B24B; B24B31/00; B24B31/10; B24B31/104; B24B31/112; B24B37/00; B24B37/04; H; H10; H10P; H10P52/00; H10P52/40; H10P52/402; H10P95/00; H10P95/06; H10P95/062; H10W; H10W20/00; H10W20/01; H10W20/071; H10W20/092
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
57 words
An apparatus for planarizing a surface of an integrated circuit wafer comprising: means for applying a quantity of a liquid, having a viscosity between about 10 -2 and 10 10 poise, to said surface; means for applying an artificial gravitational force in a direction normal to said surface; and means for converting the liquid to a solid.
Claim 2
Independent Claim
57 words
An apparatus for planarizing a surface of an integrated circuit wafer comprising: means for applying a quantity of a liquid, having a viscosity between about 10 -2 and 10 10 poise, to said surface; means for applying an artificial gravitational force in a direction normal to said surface; and means for converting the liquid to a solid.
Claim 3
Dependent Claim
28 words
The apparatus of claim 1 wherein said means for applying an artificial gravitational force further comprises means for moving the wafer in a direction normal to its surface.
Claim 4
Dependent Claim
44 words
The apparatus of claim 2 wherein said means for moving the wafer, in a direction normal to its surface, further comprises: a first magnetic coil, mounted in fixed spatial relationship relative to the wafer; and a second magnetic coil mounted in a fixed position.
Claim 5
Dependent Claim
19 words
The apparatus of claim 3 wherein the first coil is concentric with, and positioned inside of, the second coil.
Claim 6
Dependent Claim
18 words
The apparatus of claim 3 wherein the first coil is coaxial with, and positioned above, the second coil.
Claim 7
Dependent Claim
49 words
The apparatus of claim 2 wherein said means for moving the wafer, in a direction normal to its surface, further comprises: an isolation chamber in which the wafer is placed; means for increasing gas pressure below the isolation chamber; and means for decreasing gas pressure above the isolation chamber.
Claim 8
Dependent Claim
68 words
The apparatus of claim 2 wherein said means for moving the wafer, in a direction normal to its surface, further comprises an isolation chamber in which the wafer is placed; an electric motor; a flexible connector, having first and second ends, vertically attached at its first end to the isolation chamber; and means for enabling the electric motor to pull on said flexible connector from said second end.
Claim 9
Dependent Claim
24 words
The apparatus of claim 7 further comprising a set of gears, having a mechanical advantage less than 1, between said first and second ends.
Claim 10
Dependent Claim
24 words
The apparatus of claim 7 further comprising a set of pulleys, having a mechanical advantage less than 1, between said first and second ends.
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) | 2002-02-01 | 2002-08-03 | 2003-02-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-02-01 | 2006-08-03 | 2007-02-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-02-01 | 2010-08-03 | 2011-02-02 | $7700.00 | Window Closed / Lapsed |