US4968581A
Expired / Lapsed
US
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High resolution photoresist of imide containing polymers
Assignee: Clariant Finance BVI Ltd
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Filing: 1989-06-06
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Granted: 1990-11-06
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Expires: 2009-06-06
Abstract
Abstract Photoresist compositions suitable for deep UV and excimer laser lithography are disclosed that are mixtures of a photoacid and a polymer having imide residues to which acid labile groups are attached. These compositions provide high resolution, high contrast and high sensitivity in the deep UV (wavelength of 250-300 nm), mid-UV (wavelength of 300-350 nm) or conventional (wavelength of 350-450 nm) exposure bands. The compositions are also suitable for exposure at wavelengths commonly associated with excimer laser sources (248, 308 nm) or for exposure by X-radiation. In the compositions disclosed, the imide group ##STR1## can be blocked with certain groups, X, to form compounds containing the structure ##STR2## which have solubility properties different from the unblocked imide. These groups, X, can be cleaved by acid under the proper conditions to regenerate the unblocked imide. Also, where the imide group is incorporated in a polymer, the polymer with blocked imide groups can be made to function as a resist when compounded with a substance capable of forming an acid upon exposure to radiation. The exact nature of the imide containing polymer is not critical, providing that: (1) in the unblocked state, the polymer is completely soluble in aqueous alkali; (2) in the blocked state, it is insoluble in the same aqueous solution, while simultaneously; (3) in the blocked state, it is soluble in a solvent capable of dissolving a suitable sensitizer; and (4) it is film forming. Other secondary properties may be selected (to enhance the characteristics of the resist) by varying the structure of the imide or a comonomer.
Inventors
- 👤 Chengjiu Wu
- 👤 Anne M. Mooring
- 👤 Michael J. McFarland
- 👤 Christopher E. Osuch
- 👤 James T. Yardley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:13
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/022; G03F7/023; G03F7/0233; G03F7/039
Claims Analysis
Total Claims: 44
Claim 1
Independent Claim
81 words
An article comprising a substrate and a dried photoresist composition on the substrate, the photoresist composition comprising a mixture of: (a) from 1 to 50% by weight of a latent photoacid; and (b) from 50 to 99% by weight of a film forming imide containing polymer having a sufficient number of imide N-H groups replaced by acid labile groups to render the polymer insoluble in aqueous alkali, the composition comprising a solvent which dissolves both the latent photoacid and the polymer.
Claim 2
Dependent Claim
81 words
An article comprising a substrate and a dried photoresist composition on the substrate, the photoresist composition comprising a mixture of: (a) from 1 to 50% by weight of a latent photoacid; and (b) from 50 to 99% by weight of a film forming imide containing polymer having a sufficient number of imide N-H groups replaced by acid labile groups to render the polymer insoluble in aqueous alkali, the composition comprising a solvent which dissolves both the latent photoacid and the polymer.
Claim 3
Independent Claim
110 words
A method of producing a positive tone relief image on a semiconductor substrate comprising forming a photoresist composition comprising a mixture of: (a) from 1 to 50% by weight of a latent photoacid; and (b) from 50% to 99% by weight of a film forming imide containing polymer having a sufficient number of imide N-H groups replaced by acid labile groups to render the polymer insoluble in aqueous alkali; coating the composition on a semiconductor substrate; drying the composition; imagewise exposing the composition to imaging radiation; deblocking at least a portion of the imides; and developing the composition with an aqueous alkaline developer to thereby produce a positive relief image.
Claim 4
Independent Claim
110 words
A method of producing a positive tone relief image on a semiconductor substrate comprising forming a photoresist composition comprising a mixture of: (a) from 1 to 50% by weight of a latent photoacid; and (b) from 50% to 99% by weight of a film forming imide containing polymer having a sufficient number of imide N-H groups replaced by acid labile groups to render the polymer insoluble in aqueous alkali; coating the composition on a semiconductor substrate; drying the composition; imagewise exposing the composition to imaging radiation; deblocking at least a portion of the imides; and developing the composition with an aqueous alkaline developer to thereby produce a positive relief image.
Claim 5
Independent Claim
111 words
A method of producing a negative tone relief image on a semiconductor substrate, comprising forming a photoresist composition of comprising a mixture of: (a) from 1 to 50% by weight of a latent photoacid; and (b) from 50 to 99% by weight of a film forming imide containing polymer having a sufficient number of imide N-H groups replaced by acid labile groups to render the polymer insoluble in aqueous alkali; coating the composition on a semiconductor substrate; drying the composition; imagewise exposing the composition to imaging radiation; deblocking at least a portion of the imides; and developing the composition with an organic non-polar developer to thereby produce a negative relief image.
Claim 6
Independent Claim
111 words
A method of producing a negative tone relief image on a semiconductor substrate, comprising forming a photoresist composition of comprising a mixture of: (a) from 1 to 50% by weight of a latent photoacid; and (b) from 50 to 99% by weight of a film forming imide containing polymer having a sufficient number of imide N-H groups replaced by acid labile groups to render the polymer insoluble in aqueous alkali; coating the composition on a semiconductor substrate; drying the composition; imagewise exposing the composition to imaging radiation; deblocking at least a portion of the imides; and developing the composition with an organic non-polar developer to thereby produce a negative relief image.
Claim 7
Dependent Claim
66 words
An article which comprises a substrate and a dried light composition on said substrate, which composition comprises (i) from 1 to 50 by weight percent of a latent photoacid and (ii) from 50 to 99 by weight percent of a film forming imide containing polymer having a sufficient number of imide N-H groups replaced by acid labile groups to render the polymer insoluble in aqueous alkali.
Claim 8
Dependent Claim
66 words
An article which comprises a substrate and a dried light composition on said substrate, which composition comprises (i) from 1 to 50 by weight percent of a latent photoacid and (ii) from 50 to 99 by weight percent of a film forming imide containing polymer having a sufficient number of imide N-H groups replaced by acid labile groups to render the polymer insoluble in aqueous alkali.
Claim 9
Dependent Claim
13 words
The article of claim 4 wherein the latent photoacid is an iodonium salt.
Claim 10
Dependent Claim
29 words
The article of claim 5 wherein the iodonium salt is selected from the group consisting of a diphenyl iodonium salt, a 4-methylphenyl iodonium salt, and a 4-methoxyphenyl iodonium salt.
Claim 11
Dependent Claim
26 words
The article of claim 6 wherein the iodonium salt is selected from the group consisting of diphenyl iodonium triflate; di-4-methylphenyl iodonium triflate; and (4-methoxyphenyl)phenyl iodonium triflate.
Claim 12
Dependent Claim
13 words
The article of claim 4 wherein the latent photoacid is a sulfonium salt.
Claim 13
Dependent Claim
29 words
The article of claim 8 wherein the sulfonium salt is selected from the group consisting of a phenyl sulfonium salt; a methylphenyl sulfonium salt, and a 4-methoxyphenyl sulfonium salt.
Claim 14
Dependent Claim
14 words
The article of claim 9 wherein the sulfonium salt is a triphenyl sulfonium triflate.
Claim 15
Dependent Claim
12 words
The article of claim 4 wherein the latent photoacid is a diazonaphthoquinone.
Claim 16
Dependent Claim
10 words
The article of claim 11 wherein the diazonaphthoquinone is 2,4-bis(1,2-dihydro-1-oxo-2-diazonaphthalene-4-sulfonato)benzophenone.
Claim 17
Dependent Claim
15 words
The article of claim 4 wherein the imide containing polymer contains succinimide or glutarimide residues.
Claim 18
Dependent Claim
16 words
The article of claim 13 wherein the imide containing polymer is poly-co(maleimide styrene) or poly-co(maleimide-4-tertbutyl styrene).
Claim 19
Dependent Claim
21 words
The article of claim 14 wherein 50 to 100% of the imide of N-H groups are replaced with acid labile groups.
Claim 20
Dependent Claim
14 words
The article of claim 13 wherein the acid labile group is an oxycarbonyl group.
Claim 21
Dependent Claim
15 words
The article of claim 16 wherein the oxycarbonyl group is tert-butoxy carbonyl or benzyloxy carbonyl.
Claim 22
Dependent Claim
14 words
The article of claim 4 wherein the imide containing polymer contains acyclic imide residues.
Claim 23
Dependent Claim
21 words
The article of claim 18 wherein in 50 to 100% of the imide N-H groups are replaced with acid labile groups.
Claim 24
Dependent Claim
14 words
The article of claim 19 wherein the acid labile group is an oxycarbonyl group.
Claim 25
Dependent Claim
21 words
The article of claim 4 wherein a sensitizer capable of transferring energy to the latent photoacid is incorporated in the composition.
Claim 26
Independent Claim
159 words
A method of producing a positive or negative image which comprises (a) forming a composition comprising (i) from 1 to 50 weight percent of a latent photoacid and (ii) from 50 to 99 weight percent of a film forming imide containing polymer having a sufficient number of imide N-H groups replaced by acid labile groups to render the polymer insoluble in aqueous alkali, the composition being dissolved in a solvent which dissolves both the latent photoacid and the polymer; and (b) coating said composition on a substrate to form a substantially uniform film of the composition on the substrate; and (c) heating said composition for a sufficient time and at a sufficient temperature to substantially dry the composition; and (d) imagewise exposing the composition to sufficient imaging energy to form a latent image; and (e) developing the composition with an aqueous alkaline solution to form a positive image or an organic nonpolar solvent developer to obtain a negative image.
Claim 27
Independent Claim
159 words
A method of producing a positive or negative image which comprises (a) forming a composition comprising (i) from 1 to 50 weight percent of a latent photoacid and (ii) from 50 to 99 weight percent of a film forming imide containing polymer having a sufficient number of imide N-H groups replaced by acid labile groups to render the polymer insoluble in aqueous alkali, the composition being dissolved in a solvent which dissolves both the latent photoacid and the polymer; and (b) coating said composition on a substrate to form a substantially uniform film of the composition on the substrate; and (c) heating said composition for a sufficient time and at a sufficient temperature to substantially dry the composition; and (d) imagewise exposing the composition to sufficient imaging energy to form a latent image; and (e) developing the composition with an aqueous alkaline solution to form a positive image or an organic nonpolar solvent developer to obtain a negative image.
Claim 28
Dependent Claim
13 words
The method of claim 22 wherein the latent photoacid is an iodonium salt.
Claim 29
Dependent Claim
29 words
The method of claim 22 wherein the iodonium salt is selected from the group consisting of a diphenyl iodonium salt, a 4-methylphenyl iodonium salt, and a 4-methoxphenyl iodonium salt.
Claim 30
Dependent Claim
26 words
The method of claim 24 wherein the iodonium salt is selected from the group consisting of diphenyl iodonium triflate; di-4-methylphenyl iodonium triflate; and (4-methoxyphenyl)phenyl iodonium triflate.
Claim 31
Dependent Claim
13 words
The method of claim 22 wherein the latent photoacid is a sulfonium salt.
Claim 32
Dependent Claim
29 words
The method of claim 26 wherein the sulfonium salt is selected from the group consisting of a phenyl sulfonium salt; a methylphenyl sulfonium salt, and a 4-methoxyphenyl sulfonium salt.
Claim 33
Dependent Claim
14 words
The method of claim 27 wherein the sulfonium salt is a triphenyl sulfonium triflate.
Claim 34
Dependent Claim
12 words
The method of claim 22 wherein the latent photoacid is a diazonaphthoquinone.
Claim 35
Dependent Claim
10 words
The method of claim 29 wherein the diazonaphthoquinone is 2,4-bis(1,2-dihydro-1-oxo-2-diazonaphthalene-4-sulfonato)benzophenone.
Claim 36
Dependent Claim
15 words
The method of claim 22 wherein the imide containing polymer contains succinimide or glutarimide residues.
Claim 37
Dependent Claim
16 words
The method of claim 31 wherein the imide containing polymer is poly-co(maleimide styrene) or poly-co(maleimide-4-tert-butyl styrene).
Claim 38
Dependent Claim
20 words
The method of claim 32 wherein 50 to 100% of the imide N-H groups are replaced with acid labile groups.
Claim 39
Dependent Claim
14 words
The method of claim 31 wherein the acid labile group is an oxycarbonyl group.
Claim 40
Dependent Claim
15 words
The method of claim 34 wherein the oxycarbonyl group is tert-butoxy carbonyl or benzyloxy carbonyl.
Claim 41
Dependent Claim
14 words
The method of claim 22 wherein the imide containing polymer contains acyclic imide residues.
Claim 42
Dependent Claim
20 words
The method of claim 36 wherein 50 to 100% of the imide N-H groups are replaced with acid labile groups.
Claim 43
Dependent Claim
14 words
The method of claim 37 wherein the acid labile group is an oxycarbonyl group.
Claim 44
Dependent Claim
21 words
The method of claim 22 wherein a sensitizer capable of transferring energy to the latent photoacid is incorporated in the composition.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-11-05 | 1994-05-07 | 1994-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-11-05 | 1998-05-07 | 1998-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-11-05 | 2002-05-07 | 2002-11-06 | $7700.00 | Window Closed / Lapsed |