US4931379A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High sensitivity resists having autodecomposition temperatures greater than about 160° C.
Assignee: International Business Machines Corp
•
Filing: 1988-11-03
•
Granted: 1990-06-05
•
Expires: 2008-11-03
Abstract
Abstract The present invention relates to increasing the autodecomposition temperature of particular resists. The resists are comprised of structures having recurrent acid labile groups which are typically pendant to the polymeric backbone. The autodecomposition temperature of a resist is increased by selecting substituent sidechains on the acid labile group which exhibit increased stability. Sidechain structures which provide increased autodecomposition stability include secondary structures capable of forming secondary carbonium ion intermediates and having an available proton adjacent to the carbonium ion formed during cleavage. Moieties which can be used as the secondary sidechain structures include secondary alkyl, including both cyclic and alicyclic alkyl, substituted deactivated secondary benzyl, and 1-(deactivated heterocyclic) secondary alkyl.
Inventors
- 👤 William R. Brunsvold
- 👤 Willard E. Conley
- 👤 Dale M. Crockatt
- 👤 Nancy E. Iwamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 03:25
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/039
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
95 words
A resist comprising at least one polymer copolymer or terpolymer comprising a maleimide or styrene as the polymer backbone having a recurrent acid labile group pendent to the polymer backbone and a photoactive compound capable of generating an acid upon exposure to radiation, wherein the improvement comprises: selecting the acid labile group from carboxylic acid esters wherein the ester portion includes a secondary alkyl substituent side chain on said acid labile group which is capable of forming a secondary carbonium ion intermediate and having an available proton adjacent to the carbonium ion formed during cleavage.
Claim 2
Dependent Claim
95 words
A resist comprising at least one polymer copolymer or terpolymer comprising a maleimide or styrene as the polymer backbone having a recurrent acid labile group pendent to the polymer backbone and a photoactive compound capable of generating an acid upon exposure to radiation, wherein the improvement comprises: selecting the acid labile group from carboxylic acid esters wherein the ester portion includes a secondary alkyl substituent side chain on said acid labile group which is capable of forming a secondary carbonium ion intermediate and having an available proton adjacent to the carbonium ion formed during cleavage.
Claim 3
Dependent Claim
17 words
The resist of claim 1 wherein the autodecomposition temperature of said resist is greater than 160° C.
Claim 4
Dependent Claim
32 words
The resist of claim 1 wherein said substituent side chain, upon acid-catalyzed deprotection of said acid labile group, is capable of forming a less stable intermediate carbonium ion than a t-butyl ion.
Claim 5
Dependent Claim
33 words
The resist of claim 1 wherein said substituent side chain is selected from the group consisting of cyclic secondary alkyl, open chain secondary alkyl, substituted deactivated secondary benzyl, and 1-(deactivated heterocyclic) secondary alkyl.
Claim 6
Dependent Claim
21 words
The resist of claim 4 wherein said cyclic and open chain secondary alkyls are comprised of up to 10 carbon atoms.
Claim 7
Dependent Claim
21 words
The resist of claim 5 wherein said cyclic and open chain secondary alkyls are comprised of up to 6 carbon atoms.
Claim 8
Dependent Claim
22 words
The resist of claim 6 wherein said secondary alkyls are selected from the group consisting of cyclohexyl, sec-butyl, isopropyl, isobutyl, and 2-pentyl.
Claim 9
Dependent Claim
52 words
The resist of claim 4 wherein said substituted deactivated secondary benzyl is selected from the group consisting of 1-(4-nitrophenyl)alkyl, 1-(3methoxyphenyl)alkyl, and 1-(4-methoxycarbonyl-phenyl)alkyl, wherein the alkyl group comprises up to 4 carbon atoms, and 1(3-halophenyl alkyl, wherein the halogen is Cl, Br, or I, wherein the alkyl comprises up to 4 carbon atoms.
Claim 10
Dependent Claim
23 words
The resist of claim 8 wherein said substituted deactivated secondary benzyl is selected from the group consisting of 1-(4-nitrophenyl) ethyl and 1-(3-methoxyphenyl) ethyl.
Claim 11
Dependent Claim
25 words
The resist of claim 4 wherein said 1-(deactivated heterocyclic) secondary alkyl is selected from the group consisting of 1-(2-tetrahydrofurfuryl) alkyl, (1-(2-pyridyl) alkyl and 1-(4-pyridyl) alkyl.
Claim 12
Dependent Claim
14 words
The resist of claim 10 wherein said 1-(deactivated heterocyclic) secondary alkyl is 1-(2-tetrahydrofurfuryl) ethyl.
References Cited (Backward Citations)
US3779778A
Cited
US4286049A
Cited
US4491628A
Cited
US4678737A
Cited
US4663268A
Cited
US4603101A
Cited
US4845009A
Cited
US4689289A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-06-04 | 1993-12-04 | 1994-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-04 | 1997-12-04 | 1998-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-04 | 2001-12-04 | 2002-06-05 | $7700.00 | Window Closed / Lapsed |