Patent US4051271A successfully refreshed from Google Patents.
US4051271A
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Method for forming images by irradiation of electron rays and resist compositions utilizable therefor
Assignee: National Institute of Advanced Industrial Science and Technology
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Filing: 1976-03-18
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Granted: 1977-09-27
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Expires: 1996-03-18
Abstract
Abstract Syndiotactic poly(methyl methacrylate) obtained by radical polymerization mixed with isotactic poly(methyl methacrylate) obtained by anionic polymerization so that the ratio by weight of the syndiotactic component to the isotactic component is from 2:8 to 8:2 and the mixture is dissolved homogeneously in a non-polar solvent such as benzene or toluene. The resist composition thus obtained is applied onto a substrate to form a photosensitive element which is then exposed to electron rays to cause depolymerization of the polymer in the exposed areas and developed with an organic solvent to form an image which is excellent in contrast and resolving power and devoid of pinholes.
Inventors
- 👤 Shoei Fujishige
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:22
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/039; Y; Y10; Y10S; Y10S430/00; Y10S430/143
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
71 words
A method for forming images characterized by applying onto a substrate a thin film of a sterocomplex composed of syndiotactic poly(methyl methacrylate) obtained by radical polymerization and poly(methyl methacrylate) obtained by anionic polymerization and containing the isotactic structure, exposing said thin film to irradiation by electron rays through an original to effect depolymerization of the polymer in the exposed areas and thereafter washing off the depolymerized substance with an organic solvent.
Claim 2
Independent Claim
71 words
A method for forming images characterized by applying onto a substrate a thin film of a sterocomplex composed of syndiotactic poly(methyl methacrylate) obtained by radical polymerization and poly(methyl methacrylate) obtained by anionic polymerization and containing the isotactic structure, exposing said thin film to irradiation by electron rays through an original to effect depolymerization of the polymer in the exposed areas and thereafter washing off the depolymerized substance with an organic solvent.
Claim 3
Dependent Claim
45 words
A method according to claim 1 wherein said stereocomplex is composed of said syndiotactic poly(methyl methacrylate) and said poly(methyl methacrylate) containing the isotactic structure in such proportion that the ratio by weight of said syndiotactic component to said isotactic component is from 2:8 to 8:2.
Claim 4
Dependent Claim
44 words
A method according to claim 1 wherein said stereocomplex is composed of said syndiotactic poly(methyl methacrylate) having an average molecular weight of 20,000-1 million and of said poly(methyl methacrylate) having the isotactic structure and an average molecular weight from 10,000 to several hundred thousand.
Claim 5
Dependent Claim
47 words
A method according to claim 1 wherein said syndiotactic poly(methyl methacrylate) and said poly(methyl methacrylate) having the isotactic structure are dissolved in said non-polar solvent and applied onto said substrate and thereafter said solvent is removed to form a thin film of said stereocomplex on the substrate.
Claim 6
Dependent Claim
21 words
A method according to claim 1 wherein the dose of electron rays is from 10 -5 -10 -6 coulomb/cm 2 .
Claim 7
Dependent Claim
19 words
A method according to claim 1 wherein said organic solvent is a mixture of a ketone and an alcohol.
Claim 8
Dependent Claim
54 words
A resist material capable of affording images by irradiation with electron rays which comprises a substrate coated with a thin film of a stereocomplex composed of syndiotactic poly(methyl methacrylate) obtained by radical polymerization and poly(methyl methacrylate) obtained by anionic polymerization and having the isotactic structure in a ratio by weight of 2:8 to 8:2.
Claim 9
Dependent Claim
54 words
A resist material capable of affording images by irradiation with electron rays which comprises a substrate coated with a thin film of a stereocomplex composed of syndiotactic poly(methyl methacrylate) obtained by radical polymerization and poly(methyl methacrylate) obtained by anionic polymerization and having the isotactic structure in a ratio by weight of 2:8 to 8:2.
Claim 10
Dependent Claim
48 words
A resist material according to claim 7 wherein said stereocomplex is composed of said syndiotactic poly(methyl methacrylate) having an average molecular weight of 20,000-1 million and of said poly(methyl methacrylate) having the isotactic structure and an average molecular weight within a range from 10,000 to several hundred thousand.
Claim 11
Dependent Claim
60 words
A resist composition capable of affording images by irradiation with electron rays which comprises a non-polar solvent having dissolved therein syndiotactic poly(methyl methacrylate) obtained by radical polymerization and poly(methyl methacrylate) obtained by anionic polymerization and having the isotactic structure in such proportion that the ratio by weight of the syndiotactic component to the isotactic component is from 2:8 to 8:2.
Claim 12
Dependent Claim
60 words
A resist composition capable of affording images by irradiation with electron rays which comprises a non-polar solvent having dissolved therein syndiotactic poly(methyl methacrylate) obtained by radical polymerization and poly(methyl methacrylate) obtained by anionic polymerization and having the isotactic structure in such proportion that the ratio by weight of the syndiotactic component to the isotactic component is from 2:8 to 8:2.
Claim 13
Dependent Claim
39 words
A resist composition according to claim 9 wherein said syndiotactic poly(methyl methacrylate) has an average molecular weight of 20,000-1 million and said poly(methyl methacrylate) having the isotactic structure has an average molecular weight from 10,000 to several hundred thousand.
Claim 14
Dependent Claim
19 words
A resist composition according to claim 9 wherein both poly(methyl methacrylates) have been subjected to a molecular weight-fractionating treatment.
References Cited (Backward Citations)
US3779806A
Cited
US3934057A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-09-26 | 1981-03-28 | 1981-09-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-09-26 | 1985-03-28 | 1985-09-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-09-26 | 1989-03-28 | 1989-09-27 | $7700.00 | Window Closed / Lapsed |