Patent FR2546409A1 successfully refreshed from Google Patents.
US4087569A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Prebaking treatment for resist mask composition and mask making process using same
Assignee: International Business Machines Corp
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Filing: 1976-12-20
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Granted: 1978-05-02
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Expires: 1996-12-20
Abstract
Abstract Polymethyl methacrylate methacrylic acid (P[MMA/MAA]) copolymer powder is prebaked above 200° C. The prebaked powder is dissolved in a suitable casting solvent. The insoluble material produced during prebaking is removed by filtration. Then the solution remaining is applied to a substrate, post-baked at a temperature less than or equal to the prebaking temperature to drive off the solvent, exposed to electron beam radiation, and developed in a developing solvent.
Inventors
- 👤 Michael Hatzakis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:04
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/039; Y; Y10; Y10S; Y10S430/00; Y10S430/136
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
151 words
A method for the production of a resist image comprising the steps of: prebaking a dry powder of a radiation-sensitive polymeric material comprising polymethyl methacrylate/methacrylic acid copolymer at a first temperature below the decomposition temperature, adding a solvent for said polymeric material to the yield of said prebaking step to produce a solution of said polymeric material and an insoluble residue, then separating said solution from said residue and retaining said solution, coating only said solution of polymeric material without said residue upon a substrate to form a thin polymeric film of said polymeric material, post-baking said substrate and said polymeric film at a second temperature less than or equal to said first temperature and above the evaporation point of said solvent for a predetermined time required for drying said polymeric ffilm at said second temperature, exposing said polymeric film to radiation in a predetermined pattern, and developing said polymeric film.
Claim 2
Independent Claim
151 words
A method for the production of a resist image comprising the steps of: prebaking a dry powder of a radiation-sensitive polymeric material comprising polymethyl methacrylate/methacrylic acid copolymer at a first temperature below the decomposition temperature, adding a solvent for said polymeric material to the yield of said prebaking step to produce a solution of said polymeric material and an insoluble residue, then separating said solution from said residue and retaining said solution, coating only said solution of polymeric material without said residue upon a substrate to form a thin polymeric film of said polymeric material, post-baking said substrate and said polymeric film at a second temperature less than or equal to said first temperature and above the evaporation point of said solvent for a predetermined time required for drying said polymeric ffilm at said second temperature, exposing said polymeric film to radiation in a predetermined pattern, and developing said polymeric film.
Claim 3
Dependent Claim
22 words
A method in accordance with claim 1 wherein subsequent to adding said solvent, said solution is filtered prior to said coating step.
Claim 4
Dependent Claim
17 words
A method in accordance with claim 1 wherein said polymeric film is developed in a developing solvent.
Claim 5
Dependent Claim
28 words
A method in accordance with claim 1 wherein said powder is prebaked at a temperature in the range between 200° C to the decomposition temperature of said copolymer.
Claim 6
Dependent Claim
23 words
A method in accordance with claim 1 in which said powder is prebaked at a temperature below the decomposition temperature of said copolymer.
Claim 7
Dependent Claim
15 words
A method in accordance with claim 1 wherein said powder is prebaked at 220° C.
Claim 8
Dependent Claim
15 words
A method in accordance with claim 4 wherein said powder is prebaked at 230° C.
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) | 1981-05-01 | 1981-10-31 | 1982-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-01 | 1985-10-31 | 1986-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-01 | 1989-10-31 | 1990-05-02 | $7700.00 | Window Closed / Lapsed |