US4515828A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Planarization method
Assignee: International Business Machines Corp
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Filing: 1981-01-02
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Granted: 1985-05-07
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Expires: 2001-01-02
Abstract
Abstract A process for producing an extremely smooth or planarized layer of material employs a polymeric material which, when melted has a viscosity enabling it to flow into all crevices and voids on the treated surface. Subsequent heating cures the polymer to form a planarized layer.
Inventors
- 👤 James Economy
- 👤 Mary A. Flandera
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:35
CPC Classifications
B; B05; B05D; B05D7/00; B05D7/24; G; G11; G11B; G11B5/00; G11B5/84
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
86 words
A method of providing a planarized coating on a surface comprising the steps of applying a uniform coating of a prepolymer material selected from the group consisting of diacetylenic prepolymers, novolaks, epoxies and polyimides to said surface, heating said prepolymer to melt said prepolymer to a low viscosity, maintaining said low viscosity prepolymer in a melted phase for a sufficient length of time to permit said prepolymer to flow to form a planarized layer on said surface, and curing said planarized prepolymer into a planarized layer.
Claim 2
Independent Claim
86 words
A method of providing a planarized coating on a surface comprising the steps of applying a uniform coating of a prepolymer material selected from the group consisting of diacetylenic prepolymers, novolaks, epoxies and polyimides to said surface, heating said prepolymer to melt said prepolymer to a low viscosity, maintaining said low viscosity prepolymer in a melted phase for a sufficient length of time to permit said prepolymer to flow to form a planarized layer on said surface, and curing said planarized prepolymer into a planarized layer.
Claim 3
Dependent Claim
21 words
A method in accordance with claim 1, in which said surface is associated with either first or second level semiconductor packaging.
Claim 4
Dependent Claim
16 words
A method in accordance with claim 1, in which said prepolymer is cured by continued heating.
Claim 5
Dependent Claim
15 words
A method in accordance with claim 1, in which said prepolymer material is poly triethynylbenzene.
Claim 6
Dependent Claim
33 words
A method in accordance with claim 1, in which said prepolymer coating is applied to said surface while said surface is rotating, to uniformly distribute said coating over said surface by centrifugal force.
Claim 7
Dependent Claim
15 words
A method in accordance with claim 1, in which said surface is a semiconductor chip.
Claim 8
Dependent Claim
16 words
A method in accordance with claim 4, in which said surface is a metallic disk substrate.
Claim 9
Dependent Claim
27 words
A method in accordance with claim 5, including the additional step of applying a magnetic recording layer to said planarized layer to produce a magnetic recording disk.
References Cited (Backward Citations)
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US4258079A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-05-06 | 1988-11-05 | 1989-05-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-06 | 1992-11-05 | 1993-05-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-06 | 1996-11-05 | 1997-05-07 | $7700.00 | Window Closed / Lapsed |