Patent US3981985A successfully refreshed from Google Patents.
US3981985A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Positive-working electron resists
Assignee: US Philips Corp
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Filing: 1973-12-12
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Granted: 1976-09-21
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Expires: 1993-12-12
Abstract
Abstract A cross-linkable positive resist formed from mixtures of a copolymer of an olefinically unsaturated carboxylic acid and an olefinically unsaturated compound having no free acid group and a copolymer of olefinically unsaturated acid chloride and an olefinically unsaturated compound having no acid chloride group.
Inventors
- 👤 Edward David Roberts
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:43
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/039
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
147 words
A cross-linkable positive working electron resist comprising a mixture of copolymers A - B and D - E wherein: A is an unsaturated carboxylic acid of the formula ##EQU1## B is an unsaturated organic compound of the formula ##EQU2## D is an unsaturated acid chloride of the formula ##EQU3## E is an unsaturated compound of the formula ##EQU4## wherein R 1 , R 2 , R 3 , R 4 , R 6 , R 7 , R 8 and R 9 are each moieties selected from the group consisting of aryl, alkyl and hydrogen, R 5 and R 10 are each moieties selected from the group consisting of alkyl, saturated acyloxy, aryl and -COOR wherein R is alkyl, wherein the mixture contains essentially stoichiometric + or -50% quantities of A and D and wherein from 0.5 - 7.5 mol % of the mixture consists of A.
Claim 2
Dependent Claim
147 words
A cross-linkable positive working electron resist comprising a mixture of copolymers A - B and D - E wherein: A is an unsaturated carboxylic acid of the formula ##EQU1## B is an unsaturated organic compound of the formula ##EQU2## D is an unsaturated acid chloride of the formula ##EQU3## E is an unsaturated compound of the formula ##EQU4## wherein R 1 , R 2 , R 3 , R 4 , R 6 , R 7 , R 8 and R 9 are each moieties selected from the group consisting of aryl, alkyl and hydrogen, R 5 and R 10 are each moieties selected from the group consisting of alkyl, saturated acyloxy, aryl and -COOR wherein R is alkyl, wherein the mixture contains essentially stoichiometric + or -50% quantities of A and D and wherein from 0.5 - 7.5 mol % of the mixture consists of A.
Claim 3
Dependent Claim
19 words
A cross-linkble positive-working electron resist as claimed in claim 1, wherein the alkyl groups are methyl or ethyl groups.
Claim 4
Dependent Claim
28 words
A cross-linkable positive-working electron resist as claimed in claim 1, wherein none of R 4 , R 5 , R 9 and R 10 is a hydrogen atom.
Claim 5
Dependent Claim
97 words
A method of producing a resist pattern on a substrate, comprising the steps of applying a coating of a cross-linkable positive-working electron resist as claimed in claim 1 to the substrate, heating the coated substrate so as to form carboxylic acid anhydride cross-links between the groups A and D of the co-polymers A-B and D-E, irradiating the cross-linked resist coating with electrons in accordance with a desired pattern until the acid anhydride cross-links have been broken, and developing the irradiated coating by means of a solvent so as to leave the positive resist pattern on the substrate.
Claim 6
Dependent Claim
13 words
A substrate bearing a resist pattern produced by the method of claim 4.
Claim 7
Dependent Claim
23 words
A method as claimed in claim 1, wherein the irradiated coating is developed with acetone, methyl ethyl ketone, methyl isobutyl ketone or toluene.
Claim 8
Dependent Claim
27 words
A method as claimed in claim 5, wherein before irradiation of the coating with electrons noncross-linked material is leached from the coating by means of a solvent.
Claim 9
Dependent Claim
26 words
A cross-linkable positive-working electron resist as claimed in claim 10 wherein B and E are methyl methacrylate, A is methacrylic acid and D is methacryloyl chloride.
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) | 1979-09-21 | 1980-03-22 | 1980-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-09-21 | 1984-03-22 | 1984-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-09-21 | 1988-03-22 | 1988-09-21 | $7700.00 | Window Closed / Lapsed |