U.S. patent application number 10/126191 was filed with the patent office on 2002-10-31 for polymer and photoresist compositions.
This patent application is currently assigned to Shipley Company, L.L.C.. Invention is credited to Barclay, George G., Szmanda, Charles R., Trefonas, Peter III, Yueh, Wang.
Application Number | 20020160302 10/126191 |
Document ID | / |
Family ID | 24036180 |
Filed Date | 2002-10-31 |
United States Patent
Application |
20020160302 |
Kind Code |
A1 |
Szmanda, Charles R. ; et
al. |
October 31, 2002 |
Polymer and photoresist compositions
Abstract
Disclosed are spirocyclic olefin polymers, methods of preparing
spirocyclic olefin polymers, photoresist compositions including
spirocyclic olefin resin binders and methods of forming relief
images using such photoresist compositions.
Inventors: |
Szmanda, Charles R.;
(Westborough, MA) ; Barclay, George G.;
(Jefferson, MA) ; Trefonas, Peter III; (Medway,
MA) ; Yueh, Wang; (Shrewsbury, MA) |
Correspondence
Address: |
S. Matthew Cairns
c/o EDWARDS & ANGELL, LLP
Dike, Bronstein, Roberts & Cushman, IP Group
P.O. Box 9169
Boston
MA
02209
US
|
Assignee: |
Shipley Company, L.L.C.
Marlborough
MA
|
Family ID: |
24036180 |
Appl. No.: |
10/126191 |
Filed: |
April 20, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10126191 |
Apr 20, 2002 |
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09511726 |
Feb 24, 2000 |
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6406828 |
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Current U.S.
Class: |
430/270.1 ;
430/325; 526/281 |
Current CPC
Class: |
G03F 7/039 20130101;
Y10S 430/108 20130101; C08F 32/08 20130101; G03F 7/0397 20130101;
G03F 7/0045 20130101; G03F 7/0395 20130101 |
Class at
Publication: |
430/270.1 ;
430/325; 526/281 |
International
Class: |
G03F 007/004 |
Claims
What is claimed is:
1. A polymer comprising as polymerized units one or more
spirocyclic olefin monomers, wherein the spirocyclic olefin
monomers are bound to the polymer backbone through the olefinic
carbons, and optionally one or more ethylenically or acetylenically
unsaturated monomers.
2. The polymer of claim 1 wherein the spirocyclic olefin monomer
has the formula 57wherein A.dbd.O, S, CH.sub.2, and NR.sup.1;
R.sup.1=phenyl, substituted phenyl, benzyl, substituted benzyl,
(C.sub.1-C.sub.8)alkyl and substituted (C.sub.1-C.sub.8)alkyl;
G.dbd.C(Z'), O, S, and NR.sup.2; R.sup.2.dbd.(C.sub.1-C.sub.8)alkyl
and substituted (C.sub.1-C.sub.8)alkyl; E and W are independently
selected from C(Z'), O, NR.sup.2 and a chemical bond; Z'.dbd.O or
S; n=0 to 3; m=0 to 2; m'=0 to 2; l=0 to 5; and p=0 to 5; provided
that l+p=3 to 5; provided that when A.dbd.O, S or NR.sup.1, n=1;
wherein T and L are taken together and selected from a double bond
or a 5 to 8-membered unsaturated ring.
3. The polymer of claim 1 wherein the spirocyclic olefin monomer
comprises one or more electron withdrawing groups within at least
one of the spirocyclic rings.
4. The polymer of claim 3 wherein the electron withdrawing group is
selected from anhydrides, thioanhydrides, lactones, thiolactones,
imides, thioimides, lactams and thiolactams.
5. The polymer of claim 4 wherein the electron withdrawing group is
selected from anhydrides, lactones, imides or lactams.
6. The polymer of claim 3 wherein the spirocyclic monomer is
selected form the monomers of Formulae II and III 58wherein
Z.dbd.CH.sub.2, C(O), C(S), O or S; X and Y are independently
selected from CH.sub.2, C(O), C(S), O or NR.sup.2; and
R.sup.2.dbd.(C.sub.1-C.sub.8)alkyl and substituted
(C.sub.1-C.sub.8)alkyl; provided that at least one of X, Y and Z is
selected from C(O) or C(S); and wherein the spirocyclic monomer is
optionally substituted.
7. The polymer of claim 6 wherein Z is C(O) and X is oxygen.
8. The polymer of claim 1 having the Formula VIa or VIb 59wherein
Z.dbd.CH.sub.2, C(O), C(S), O or S; X and Y are independently
selected from CH.sub.2, C(O), C(S), O or NR.sup.2;
R.sup.2.dbd.(C.sub.1-C.sub.8)al- kyl and substituted
(C.sub.1-C.sub.8)alkyl; R.sup.3.dbd.C(O)O(CH.sub.2).su- b.qOH, H,
and C(O)OR.sup.4; R.sup.4.dbd.(C.sub.1-C.sub.24)alkyl and H;
J.dbd.C(O)O--, Ar--O-- and (CH.sub.2).sub.n'C(CF.sub.3).sub.2--O--;
LG is a leaving group having 4 or more carbon atoms with at least
one quaternary carbon atom bonded directly to the carboxyl group; q
is an integer from 0 to 20; n'=0 to 4; r is 10 to 60 percent by
weight of the monomer unit, based on the total weight of the
monomers; r' is 10 to 80 percent by weight of the monomer unit,
based on the total weight of the monomers; t is 10 to 90 percent by
weight of the monomer unit, based on the total weight of the
monomers; t' is 20 to 90 percent by weight of the monomer unit,
based on the total weight of the monomers; and p is 0 to 80 percent
by weight of the monomer unit, based on the total weight of the
monomers.
9. The polymer of claim 8 wherein LG is selected from isobutyl,
2,3-dimethylbutyl, 2,3,4-trimethylpentyl and alicyclic leaving
groups.
10. The polymer of claim 9 wherein the alicyclic leaving group is
selected from 60
11. A method of polymerizing one or more spirocyclic olefinic
monomers to form a polymer comprising as polymerized units one or
more spirocyclic olefin monomers, comprising the step of contacting
the one or more spirocyclic olefinic monomers with one or more
catalysts selected from palladium(II) polymerization catalyst,
nickel(II) polymerization catalyst or free radical polymerization
catalyst.
12. The method of claim 11 wherein the palladium(II) catalyst
comprises palladium dihalide, nonionic palladium(II)-halide
complexes, (Pd(RCN).sub.4)(BF.sub.4).sub.2, where R is
(C.sub.1-C.sub.4)alkyl, palladium(II)-alkyl complexes, and
(.eta..sup.3-allyl)palladium(II) compounds with weakly coordinating
counterions.
13. The method of claim 11 wherein the palladium(II) catalyst
comprises (Pd(RCN).sub.4)(BF.sub.4).sub.2, where R is
(C.sub.1-C.sub.4)alkyl, (.eta..sup.3-allyl)palladium(II) compounds
with weakly coordinating counterions, and mixtures thereof.
14. The method of claim 11 wherein the free radical polymerization
catalyst is selected from hydrogen peroxide, tert-butyl
hydroperoxide, sodium persulfate, potassium persulfate or lithium
persulfate.
15. The method of claim 11 wherein the nickel(II) polymerization
catalyst is selected from nickel(II) catalysts having as ligands at
least one of salicylaldimine or substituted salicylaldimine and at
least one of acetonitrile or phosphine.
16. A photoresist composition comprising a resin binder comprising
as polymerized units one or more spirocyclic olefin monomers,
wherein the spirocyclic olefin monomers are bound to the polymer
backbone through the olefinic carbons, optionally one or more
ethylenically or acetylenically unsaturated monomers and a
photoactive component.
17. The photoresist composition of claim 16 wherein the resin
binder comprises a spirocyclic polymer comprising as polymerized
units one or more spirocyclic olefin monomers of the formula
61wherein A.dbd.O, S, CH.sub.2, and NR.sup.1; R.sup.1=phenyl,
substituted phenyl, benzyl, substituted benzyl,
(C.sub.1-C.sub.8)alkyl and substituted (C.sub.1-C.sub.8)alkyl;
G.dbd.C(Z'), O, S, and NR.sup.2; R.sup.2.dbd.(C.sub.1-C.sub.8)alkyl
and substituted (C.sub.1-C8)alkyl; E and W are independently
selected from C(Z'), O, NR.sup.2 and a chemical bond; Z'.dbd.O or
S; n=0 to 3; m=0 to 2; m'=0 to 2; l=0 to 5; and p=0 to 5; provided
that l+p=3 to 5; provided that when A.dbd.O, S or NR.sup.1, n=1;
wherein T and L are taken together and selected from a double bond
or a 5 to 8-membered unsaturated ring.
18. The photoresist composition of claim 16 wherein the spirocyclic
olefin monomer comprises one or more electron withdrawing groups
within at least one of the spirocyclic rings.
19. The photoresist composition of claim 18 wherein the electron
withdrawing group is selected from anhydrides, thioanhydrides,
lactones, thiolactones, imides, thioimides, lactams or
thiolactams.
20. The photoresist composition of claim 16 further comprising a
solvent.
21. The photoresist composition of claim 20 wherein the solvent
comprises ethyl lactate, ethylene glycol monomethyl ether, ethylene
glycol monomethyl ether acetate, propylene glycol monomethyl ether,
propylene glycol monomethyl ether acetate, 3-ethoxyethyl
propionate, 2-heptanone, .gamma.-butyrolactone, and mixtures
thereof.
22. The photoresist composition of claim 21 wherein the solvent is
selected from .gamma.-butyrolactone or mixtures of
.gamma.-butyrolactone and 2-heptanone.
23. A method for forming a photoresist relief image, including the
steps of applying a coating layer of the photoresist composition of
claim 16; exposing the photoresist coating layer to patterned
activating radiation; developing the exposed photoresist coating
layer to provide a photoresist relief image.
24. The method of claim 23 wherein the photoresist composition
comprises a resin binder comprising a spirocyclic olefin polymer of
the Formula VIa or VIb 62wherein Z.dbd.CH.sub.2, C(O), C(S), O or
S; X and Y are independently selected from CH.sub.2, C(O), C(S), O
or NR.sup.2; R.sup.2.dbd.(C.sub.1-C.sub.8)alkyl and substituted
(C.sub.1-C.sub.8)alkyl; R.sup.3.dbd.C(O)O(CH.sub.2).sub.qOH, H, and
C(O)OR.sup.4; R.sup.4.dbd.(C.sub.1-C.sub.24)alkyl and H;
J.dbd.C(O)O--, Ar--O-- and (CH.sub.2).sub.n'C(CF.sub.3).sub.2--O--;
LG is a leaving group having 4 or more carbon atoms with at least
one quaternary carbon atom bonded directly to the carboxyl group; q
is an integer from 0 to 20; n'=0 to 4; r is 10 to 60 percent by
weight of the monomer unit, based on the total weight of the
monomers; t is 10 to 90 percent by weight of the monomer unit,
based on the total weight of the monomers; and p is 0 to 80 percent
by weight of the monomer unit, based on the total weight of the
monomers.
25. A compound of the formula 63wherein R.sup.1 and R.sup.3 are
independently selected from hydrogen or (C.sub.1-C.sub.8)alkyl,
R.sup.2=cyclohexyl or cyclopentyl, and R.sup.2 and R.sup.3 may be
joined to form a 5- to 7-member fused ring.
26. The compound of claim 24 wherein R.sup.1 is hydrogen or methyl.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates generally to polymer compositions
useful in photoresist compositions. In particular, this invention
relates to polymer compositions including spirocyclic olefin units
useful as binders in photoresist compositions.
[0002] Photoresists are photosensitive films used for transfer of
images to a substrate. A coating layer of a photoresist is formed
on a substrate and the photoresist layer is then exposed through a
photomask to a source of activating radiation. The photomask has
areas that are opaque to activating radiation and other areas that
are transparent to activating radiation. Exposure to activating
radiation provides a photoinduced chemical transformation of the
photoresist coating to thereby transfer the pattern of the
photomask to the photoresist-coated substrate. Following exposure,
the photoresist is developed to provide a relief image that permits
selective processing of a substrate.
[0003] A photoresist can be either positive-acting or
negative-acting. For most negative-acting photoresists, those
coating layer portions that are exposed to activating radiation
polymerize or crosslink in a reaction between a photoactive
compound and polymerizable agents of the photoresist composition.
Consequently, the exposed coating portions are rendered less
soluble in a developer solution than unexposed portions. For
positive-acting photoresists, exposed portions are rendered more
soluble in a developer solution while areas not exposed remain
comparatively less developer soluble. In general, photoresist
compositions include at least a resin binder component and a
photoactive agent.
[0004] More recently, chemically-amplified type resists have been
increasingly employed, particularly for formation of sub-micron
images and other high performance applications. Such photoresists
may be negative-acting or positive-acting and generally include
many crosslinking events (in the case of a negative-acting resist)
or deprotection reactions (in the case of a positive-acting resist)
per unit of photogenerated acid. In the case of positive
chemically-amplified resists, certain cationic photoinitiators have
been used to induce cleavage of certain "blocking" groups pendant
from a photoresist binder, or cleavage of certain groups comprising
a photoresist binder backbone. See, for example, U.S. Pat. Nos.
5,075,199; 4,968,581; 4,810,613; and 4,491,628 and Canadian Patent
Application 2,001,384. Upon cleavage of the blocking group through
exposure of a coating layer of such a resist, a polar functional
group is formed, e.g. carboxyl or imide, which results in different
solubility characteristics in exposed and unexposed areas of the
resist coating layer. See also R. D. Allen et al. Proceedings of
SPIE, 2724:334-343 (1996); and P. Trefonas et al. Proceedings of
the 11.sup.th International Conference on Photopolymers (Soc. of
Plastics Engineers), pp 44-58 (Oct. 6, 1997).
[0005] While currently available photoresists are suitable for many
applications, current resists can also exhibit significant
shortcomings, particularly in high performance applications such as
formation of highly resolved sub-half micron and sub-quarter micron
features.
[0006] Consequently, interest has increased in photoresists that
can be photoimaged with short wavelength radiation, including
exposure radiation of about 250 nm or less, or even about 200 nm or
less, such as wavelengths of about 248 nm (provided by a KrF laser)
or 193 nm (provided by an ArF exposure tool). Use of such short
exposure wavelengths can enable formation of smaller features.
Accordingly, a photoresist that yields well-resolved images upon
248 or 193 nm exposure could enable formation of extremely small
(e.g. sub-quarter micron) features that respond to constant
industry demands for smaller dimension circuit patterns, e.g. to
provide greater circuit density and enhanced device
performance.
[0007] However, many current photoresists are generally designed
for imaging at relatively higher wavelengths, such as I-line (365
nm) and G-line (436 nm) exposures, and are generally unsuitable for
imaging at short wavelengths, such as 248 nm and 193 nm. In
particular, prior resists exhibit poor resolution (if any image at
all can be developed) upon exposure to these shorter wavelengths.
Among other things, current photoresists can be highly opaque to
extremely short exposure wavelengths, such as 248 nm and 193 nm,
thereby resulting in poorly resolved images. Efforts to enhance
transparency for short wavelength exposure can negatively impact
other important performance properties such as substrate adhesion
or swelling, which in turn can dramatically compromise image
resolution.
[0008] Cyclic monomer units, particularly those containing
functional groups, impart various properties to the resin binder
when incorporated into the backbone of the resin binder. Anhydrides
incorporated into the resin binder backbone help reduce swelling.
For example, Barclay et al., The Effect of Polymer Architecture on
the Aqueous Base development of Photoresists, Polym. Prepr.
(American Chemical Society, Division of Polymer Chemistry), volume
40(1), pages 438-439, 1999, discloses the incorporation of itaconic
anhydride into a photoresist resin binder, such as a (meth)acrylic
polymer. However, such anhydrides can undergo hydrolysis in the
presence of alcohols or other solvents, especially solvents that
are contaminated with small amounts of water.
[0009] Such swelling of resin binders could be even further reduced
or eliminated through the use of a binder containing a high
proportion of cyclic monomers in the polymer backbone, particularly
cyclic monomers containing functional groups. One approach for
achieving this is to use only cyclic monomers in the preparation of
the polymer. However, this approach suffers from the difficulty in
polymerizing such cyclic monomers, especially when the cyclic
monomers contain electron withdrawing groups, such as anhydrides.
In particular, 5-norbornene-2,3-dicarboxylic anhydride cannot be
easily polymerized.
[0010] For example, WO 99/42510 discloses resins useful in
photoresist compositions wherein the resin is composed of
norbomenyl monomers containing various functional groups. This
patent application is directed to a method for preparing a
polycyclic polymer and introducing difficult to polymerize
functionalities into the polymer by post-polymerization
functionalization. Such post polymerization treatment avoids the
use of monomers containing such difficult to polymerize
functionalities as nitrogen containing groups, such as amides, and
hydroxyl containing groups, such as alcohols and carboxylic acids.
The post polymerization functionalization is achieved by using
cyclic monomers containing protected functionalities, deprotecting
the functionality to give a free functionality and then reacting
the free functionality to give a post-functionalized moiety.
Drawbacks of this invention are that the mass of the polymer resin
may change, resulting in shrinkage of the polymer, and a number of
extra steps are required which greatly adds to the time and cost of
the preparation.
[0011] Polymers containing tricyclic nornornenyl monomers composed
of a norbornenyl ring fused to a 5-membered anhydride ring are
disclosed in WO 99/42510. However, spirocyclic monomers are not
disclosed in that patent application.
[0012] Japanese Patent Application JP 10 310 640 A, to Maruzen
Petrochem Co. Ltd., discloses a variety of spirocyclic olefin
monomers including those containing lactone and imide functional
groups. Spiropolyimides are also disclosed, however, such
polyimides are bound to the polymer backbone through the imide
nitrogen groups. This patent application does not disclose
spirocyclic monomer units bound to the polymer,backbone through the
olefinic carbons of the spirocyclic olefin monomers.
[0013] It is thus desirable to have photoresist compositions that
can be imaged at short wavelengths, contain resin binders having
reduced swelling and have better substrate adhesion than known
photoresist compositions. It is further desirable to have
photoresist compositions containing resin binders that have mass
persistence and can be prepared with few reactions or
transformations.
SUMMARY OF THE INVENTION
[0014] It has been surprisingly found that polymers containing
spirocyclic monomers can be readily obtained without the use of
ring-opening polymerizations. It has also been surprisingly found
that resin binders can be prepared having a high proportion of
cyclic monomers in the polymer backbone, including cyclic monomers
having electron withdrawing functional groups. It has further been
surprisingly found that such spirocyclic resin binders include, as
polymerized units, spirocyclic monomers bound to the polymer
backbone through the monomer olefinic carbons.
[0015] In one aspect, the present invention provides a polymer
including as polymerized units one or more spirocyclic olefin
monomers, wherein the spirocyclic olefin monomers are bound to the
polymer backbone through the olefinic carbons, and optionally one
or more ethylenically or acetylenically unsaturated monomers.
[0016] In a second aspect, the present invention provides a method
of polymerizing one or more spirocyclic olefinic monomers to form a
polymer including as polymerized units one or more spirocyclic
olefin monomers, including the step of contacting the one or more
spirocyclic olefinic monomers with one or more catalysts selected
from palladium(II) polymerization catalyst, nickel(II)
polymerization catalyst and free radical polymerization
catalyst.
[0017] In a third aspect, the present invention provides a
photoresist composition including a resin binder including as
polymerized units one or more spirocyclic olefin monomers, wherein
the spirocyclic olefin monomers are bound to the polymer backbone
through the olefinic carbons, optionally one or more ethylenically
or acetylenically unsaturated monomers and a photoactive
component.
[0018] In a fourth aspect, the present invention provides a method
for forming a photoresist relief image, including the steps of
applying a coating layer of the photoresist composition described
above; exposing the photoresist coating layer to patterned
activating radiation; developing the exposed photoresist coating
layer to provide a photoresist relief image.
DETAILED DESCRIPTION OF THE INVENTION
[0019] As used throughout this specification, the following
abbreviations shall have the following meanings, unless the context
clearly indicates otherwise: .degree. C.=degrees Centigrade;
g=gram; mol=mole; mol %=percent by moles; w/w=weight per weight
basis; mmol=millimole; ml=milliliter; mm=millimeter; nm=nanometer;
Ar=aryl; and sec=second.
[0020] The terms "resin" and "polymer" are used interchangeably
throughout this specification. The term "alkyl" refers to linear,
branched and cyclic alkyl. The terms "halogen" and "halo" include
fluorine, chlorine, bromine, and iodine. Thus the term
"halogenated" refers to fluorinated, chlorinated, brominated, and
iodinated. "Polymers" refer to both homopolymers and copolymers.
The term "(meth)acrylate" refers to both acrylate and methacrylate.
Likewise, the term "(meth)acrylic" refers to both acrylic and
methacrylic.
[0021] All amounts are percent by weight and all ratios are by
weight, unless otherwise noted. All numerical ranges are
inclusive.
[0022] The present invention provides a polymer including as
polymerized units one or more spirocyclic olefin monomers. The term
"spirocyclic" as used herein has its conventional meaning, that is,
any compound containing two or more rings wherein two of the rings
have one ring carbon in common. By "spirocyclic olefin" is meant
any spirocyclic compound having a double bond. "Sprirocyclic olefin
monomer" refers to any spirocyclic olefin capable of being
polymerized.
[0023] The polymers of the present invention contain from 1 to 100
percent by weight, based on the total weight of the monomers, of
one or more spirocyclic monomers. Thus the polymers of the present
invention may be homopolymers or copolymers of spirocyclic olefin
monomers. It will be appreciated by those skilled in the art that
any ethylenically unsaturated monomer, acetylenically unsaturated
monomer or mixtures thereof may be copolymerized with the
spirocyclic olefin monomers of the present invention. Such
ethylenically or acetylenically unsaturated monomer or mixtures
thereof may be present in the polymers of the present invention in
an amount in the range of 1 to 99 percent by weight, based on the
total weight of the monomers.
[0024] Any spirocyclic olefin monomer is useful in the polymers of
the present invention. It is preferred that at least one ring of
the spirocyclic olefin monomer is a 5- to 7-membered ring, and more
preferably both spirocyclic rings are 5- to 7-membered rings.
Suitable spirocyclic olefin monomers useful in the present
invention include those of Formula I 1
[0025] wherein A.dbd.O. S, CH.sub.2, and NR.sup.1; R.sup.1=phenyl,
substituted phenyl, benzyl, substituted benzyl,
(C.sub.1-C.sub.8)alkyl and substituted (C.sub.1-C.sub.8)alkyl;
G.dbd.C(Z'), O, S, and NR.sup.2; R.sup.2.dbd.(C.sub.1-C.sub.8)alkyl
and substituted (C.sub.1-C.sub.8)alkyl; E and W are independently
selected from C(Z'), O, NR.sup.2 and a chemical bond; Z'.dbd.O or
S; n=0 to 3;m=0 to 2; m'=0 to 2; l=0 to 5; and p=0 to 5; provided
that l+p=3 to 5; provided that when A.dbd.O, S or NR.sup.1, n=1;
wherein T and L are taken together and selected from a double bond
or a 5 to 8-membered unsaturated ring.
[0026] Suitable spirocyclic monomers of the present invention
wherein T and L are joined to form a 5 to 8-membered unsaturated
ring include those having the Formula Ia 2
[0027] wherein A, E, W, G, l, m, n and p are as defined above.
[0028] It is preferred that the spirocyclic olefin monomers of the
present invention have the structure of Formula Ib 3
[0029] wherein A, E, W, G, l, m, n and p are as defined above. More
preferably, the spirocyclic olefin monomers have the structure of
Formula Ic 4
[0030] wherein A, E, W, G, l, m, n and p are as defined above. It
is further preferred that n is 1 or 2. It is still further
preferred that A is CH.sub.2. It is also preferred that m is 0 or
1.
[0031] By "substituted phenyl" is meant a phenyl ring having one or
more of its hydrogens replaced with another substituent group. By
"substituted benzyl" is meant a benzyl group having one or more of
its hydrogens replaced with another substituent group. Suitable
substituent groups include, but are not limited to, cyano, halo,
(CI-C.sub.4)alkoxy, (C.sub.1-C.sub.4)alkyl, amino,
(C.sub.1-C.sub.4)alkylamino, (C.sub.1-C.sub.4)dialkylamino,
(C.sub.1-C.sub.4)alkylthio, and the like.
[0032] The spirocyclic olefin monomers useful in the present
invention may be optionally substituted. By substituted is meant
that one or more of the hydrogens on the ring carbons is replaced
by one or more substituent groups. Suitable substituent groups
include (C.sub.1-C.sub.12)alkyl, phenyl, substituted phenyl,
(C.sub.1-C.sub.12)alkoxy, (C.sub.7-C.sub.10)alkaryl,
(C.sub.1-C.sub.8)perhaloalkyl, and halogen. Preferred substituents
are (C.sub.1-C.sub.12)alkyl, more preferably
(C.sub.1-C.sub.4)alkyl, and most preferably
(C.sub.1-C.sub.2)alkyl.
[0033] Preferred spirocyclic olefin monomers are those containing
electron withdrawing groups within at least one of the spirocyclic
rings. As used herein, spirocyclic olefin monomers containing
electron withdrawing groups are intended to include compounds
having groups such as carbonyl, thiocarbonyl, oxa, mercapto, amino,
substituted amino, amido, and the like as ring atoms. Suitable
electron withdrawing groups include, but are not limited to
anhydrides, thioanhydrides, lactones, thiolactones, imides,
thioimides, lactams and thiolactams. It is preferred that the
electron withdrawing groups are anhydrides, lactones, imides and
lactams, and more preferably anhydrides and lactones. It is further
preferred that such electron withdrawing groups are alpha to the
spirocarbon.
[0034] Suitable spirocyclic olefin monomers include, but are not
limited to, spirocyclic norbornenyl monomers, spirocyclic
cyclohexene monomers, spirocyclic cyclopentene monomers and
mixtures thereof. Suitable spirocyclic norbomenyl monomers include
those having a 5-membered spirocycle, such as those of Formulae II
and III 5
[0035] wherein Z.dbd.CH.sub.2, C(O), C(S), O or S; X and Y are
independently selected from CH.sub.2, C(O), C(S), O or NR.sup.2;
and R.sup.2.dbd.(C.sub.1-C.sub.8)alkyl and substituted
(C.sub.1-C.sub.8)alkyl; provided that at least one of X, Y and Z is
selected from C(O) or C(S); and wherein the spirocyclic monomer is
optionally substituted.
[0036] Preferred spirocyclic norbomenyl olefin monomers of Formulae
II and III are those wherein Z is C(O), and more preferably wherein
Z is C(O) and X is oxygen. Spirocyclic norbornenyl olefin monomers
having a carbonyl or thiocarbonyl in the exo position are preferred
in certain polymerizations as polymerizations of such exo monomers
are believed to be faster than that of the corresponding endo
monomers. Thus, for example, spirocyclic norbornenyl olefin
monomers of Formula II are preferred when Z is C(O) or C(S).
[0037] The spirocyclic olefinic monomers useful in the present
invention are generally known in the literature. For example,
Griffini, Heterocycles, volume 16, number 5, pages 775-788, 1981,
discloses various spirocyclic olefinic imides, herein incorporated
by reference to the extent this article teaches the preparation of
such compounds.
[0038] In general, the spirocyclic olefin monomers of the present
invention may be prepared by a Diels-Alder reaction of a cyclic
hydrocarbon containing an exo double bond with butadiene, a
substituted butadiene, a cyclodiene, such as cyclopentadiene or
1,3-cyclohexadiene, or a substituted cyclodiene. Such reaction is
illustrated in the following Reaction Scheme. 6
[0039] The ethylenically or acetylenically unsaturated monomers
that may be used in the present invention are any that will
copolymerize with the spirocyclic olefinic monomers of the present
invention. It will be appreciated by those skilled in the art that
one or more ethylenically or acetylenically unsaturated monomers
may be copolymerized with the spirocyclic olefinic monomers of the
present invention. The total amount of the ethylenic ally and
acetylenic ally monomers useful in the polymer of the present
invention is from 1 to 99 percent by weight, based on the total
weight of the monomers, preferably from 10 to 95 percent by weight,
more preferably from 20 to 90 percent by weight, and even more
preferably from 60 to 90 percent by weight.
[0040] Suitable ethylenically or acetylenically unsaturated
monomers include, but are not limited to: (meth) acrylic acid,
(meth)acrylamides, alkyl (meth)acrylates, alkenyl (meth)acrylates,
aromatic (meth)acrylates, vinyl aromatic monomers,
nitrogen-containing compounds and their thio-analogs, substituted
ethylene monomers, cyclic olefins, substituted cyclic olefins, and
the like.
[0041] Typically, the alkyl (meth)acrylates useful in the present
invention are (C.sub.1-C.sub.24)alkyl (meth)acrylates. Suitable
alkyl (meth)acrylates include, but are not limited to, "low cut"
alkyl (meth)acrylates, "mid cut" alkyl (meth)acrylates and "high
cut" alkyl (meth)acrylates.
[0042] "Low cut" alkyl (meth)acrylates are typically those where
the alkyl group contains from 1 to 6 carbon atoms. Suitable low cut
alkyl (meth)acrylates include, but are not limited to: methyl
methacrylate ("MMA"), methyl acrylate, ethyl acrylate, propyl
methacrylate, butyl methacrylate ("BMA"), butyl acrylate ("BA"),
isobutyl methacrylate ("IBMA"), hexyl methacrylate, cyclohexyl
methacrylate, cyclohexyl acrylate and mixtures thereof.
[0043] "Mid cut" alkyl (meth)acrylates are typically those where
the alkyl group contains from 7 to 15 carbon atoms. Suitable mid
cut alkyl (meth)acrylates include, but are not limited to:
2-ethylhexyl acrylate ("EHA"), 2-ethylhexyl methacrylate, octyl
methacrylate, decyl methacrylate, isodecyl methacrylate ("IDMA",
based on branched (C.sub.10)alkyl isomer mixture), undecyl
methacrylate, dodecyl methacrylate (also known as lauryl
methacrylate), tridecyl methacrylate, tetradecyl methacrylate (also
known as myristyl methacrylate), pentadecyl methacrylate and
mixtures thereof. Particularly useful mixtures include
dodecyl-pentadecyl methacrylate ("DPMA"), a mixture of linear and
branched isomers of dodecyl, tridecyl, tetradecyl and pentadecyl
methacrylates; and lauryl-myristyl methacrylate ("LMA").
[0044] "High cut" alkyl (meth)acrylates are typically those where
the alkyl group contains from 16 to 24 carbon atoms. Suitable high
cut alkyl (meth)acrylates include, but are not limited to:
hexadecyl methacrylate, heptadecyl methacrylate, octadecyl
methacrylate, nonadecyl methacrylate, cosyl methacrylate, eicosyl
methacrylate and mixtures thereof. Particularly useful mixtures of
high cut alkyl (meth)acrylates include, but are not limited to:
cetyl-eicosyl methacrylate ("CEMA"), which is a mixture of
hexadecyl, octadecyl, cosyl and eicosyl methacrylate; and
cetyl-stearyl methacrylate ("SMA"), which is a mixture of hexadecyl
and octadecyl methacrylate.
[0045] The mid-cut and high-cut alkyl (meth)acrylate monomers
described above are generally prepared by standard esterification
procedures using technical grades of long chain aliphatic alcohols,
and these commercially available alcohols are mixtures of alcohols
of varying chain lengths containing between 10 and 15 or 16 and 20
carbon atoms in the alkyl group. Examples of these alcohols are the
various Ziegler catalyzed ALFOL alcohols from Vista Chemical
company, i.e., ALFOL 1618 and ALFOL 1620, Ziegler catalyzed various
NEODOL alcohols from Shell Chemical Company, i.e. NEODOL 25 L, and
naturally derived alcohols such as Proctor & Gamble's TA-1618
and CO-1270. Consequently, for the purposes of this invention,
alkyl (meth)acrylate is intended to include not only the individual
alkyl (meth)acrylate product named, but also to include mixtures of
the alkyl (meth)acrylates with a predominant amount of the
particular alkyl (meth)acrylate named.
[0046] The alkyl (meth)acrylate monomers useful in the present
invention may be a single monomer or a mixture having different
numbers of carbon atoms in the alkyl portion. Also, the
(meth)acrylamide and alkyl (meth)acrylate monomers useful in the
present invention may optionally be substituted. Suitable
optionally substituted (meth)acrylamide and alkyl (meth)acrylate
monomers include, but are not limited to: hydroxy
(C.sub.2-C.sub.6)alkyl (meth)acrylates,
dialkylamino(C.sub.2-C.sub.6)-alk- yl (meth)acrylates,
dialkylamino(C.sub.2-C.sub.6)alkyl (meth)acrylamides.
[0047] Particularly useful substituted alkyl (meth)acrylate
monomers are those with one or more hydroxyl groups in the alkyl
radical, especially those where the hydroxyl group is found at the
.beta.-position (2-position) in the alkyl radical. Hydroxyalkyl
(meth)acrylate monomers in which the substituted alkyl group is a
(C.sub.2-C.sub.6)alkyl, branched or unbranched, are preferred.
Suitable hydroxyalkyl (meth)acrylate monomers include, but are not
limited to: 2-hydroxyethyl methacrylate ("HEMA"), 2-hydroxyethyl
acrylate ("HEA"), 2-hydroxypropyl methacrylate,
1-methyl-2-hydroxyethyl methacrylate, 2-hydroxy-propyl acrylate,
1-methyl-2-hydroxyethyl acrylate, 2-hydroxybutyl methacrylate,
2-hydroxybutyl acrylate and mixtures thereof. The preferred
hydroxyalkyl (meth)acrylate monomers are HEMA,
1-methyl-2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate
and mixtures thereof. A mixture of the latter two monomers is
commonly referred to as "hydroxypropyl methacrylate" or HPMA.
[0048] Other substituted (meth)acrylate and (meth)acrylamide
monomers useful in the present invention are those with a
dialkylamino group or dialkylaminoalkyl group in the alkyl radical.
Examples of such substituted (meth)acrylates and (meth)acrylamides
include, but are not limited to: dimethylaminoethyl methacrylate,
dimethylaminoethyl acrylate, N,N-dimethylaminoethyl methacrylamide,
N,N-dimethyl-aminopropyl methacrylamide, N,N-dimethylaminobutyl
methacrylamide, N,N-di-ethylaminoethyl methacrylamide,
N,N-diethylaminopropyl methacrylamide, N,N-diethylaminobutyl
methacrylamide, N-(1,1-dimethyl-3-oxobutyl) acrylamnide,
N-(1,3-diphenyl-1-ethyl-3-oxobut- yl) acrylamide,
N-(1-methyl-1-phenyl-3-oxobutyl) methacrylamide, and 2-hydroxyethyl
acrylamide, N-methacrylamide of aminoethyl ethylene urea,
N-methacryloxy ethyl morpholine, N-maleimide of
dimethylaminopropylamine and mixtures thereof.
[0049] Other substituted (meth)acrylate monomers useful in the
present invention are silicon-containing monomers such as
.gamma.-propyl tri(C.sub.1-C.sub.6)alkoxysilyl (meth)acrylate,
.gamma.-propyl tri(C.sub.1-C.sub.6)alkylsilyl (meth)acrylate,
.gamma.-propyl di(C.sub.1-C.sub.6)alkoxy(C.sub.1-C.sub.6)alkylsilyl
(meth)acrylate, .gamma.-propyl
di(C.sub.1-C.sub.6)alkyl(C.sub.1-C.sub.6)alkoxysilyl
(meth)acrylate, vinyl tri(C.sub.1-C.sub.6)alkoxysilyl
(meth)acrylate, vinyl
di(C.sub.1-C.sub.6)alkoxy(C.sub.1-C.sub.6)alkylsilyl
(meth)acrylate, vinyl
(C.sub.1-C.sub.6)alkoxydi(C.sub.1-C.sub.6)alkylsily- l
(meth)acrylate, vinyl tri(C.sub.1-C.sub.6)alkylsilyl
(meth)acrylate, and mixtures thereof.
[0050] The vinyl aromatic monomers useful as unsaturated monomers
in the present invention include, but are not limited to: styrene
("STY"), .alpha.-methylstyrene, vinyltoluene, p-methylstyrene,
ethylvinylbenzene, vinylnaphthalene, vinylxylenes, and mixtures
thereof. The vinylaromatic monomers also include their
corresponding substituted counterparts, such as halogenated
derivatives, i.e., containing one or more halogen groups, such as
fluorine, chlorine or bromine; and nitro, cyano,
(C.sub.1-C.sub.10)alkoxy, halo(C.sub.1-C.sub.10)alkyl,
carb(C.sub.1-C.sub.10)alkoxy, carboxy, amino,
(C.sub.1-C.sub.10)alkylamin- o derivatives and the like.
[0051] The nitrogen-containing compounds and their thio-analogs
useful as unsaturated monomers in the present invention include,
but are not limited to: vinylpyridines such as 2-vinylpyridine or
4-vinylpyridine; lower alkyl (C.sub.1-C.sub.8) substituted N-vinyl
pyridines such as 2-methyl-5-vinyl-pyridine,
2-ethyl-5-vinylpyridine, 3-methyl-5-vinylpyridine,
2,3-dimethyl-5-vinyl-pyridine, and
2-methyl-3-ethyl-5-vinylpyridine; methyl-substituted quinolines and
isoquinolines; N-vinylcaprolactam; N-vinylbutyrolactam;
N-vinylpyrrolidone; vinyl imidazole; N-vinyl carbazole;
N-vinyl-succinimide; (meth)acrylonitrile; o-, m-, or
p-aminostyrene; maleimide; N-vinyl-oxazolidone; N,N-dimethyl
aminoethyl-vinyl-ether; ethyl-2-cyano acrylate; vinyl acetonitrile;
N-vinylphthalimide; N-vinyl-pyrrolidones such as
N-vinyl-thio-pyrrolidone, 3 methyl-1-vinyl-pyrrolidone,
4-methyl-1-vinyl-pyrrolidone, 5-methyl-1-vinyl-pyrrolidone,
3-ethyl-1-vinyl-pyrrolidone, 3-butyl-1-vinyl-pyrrolidone,
3,3-dimethyl-1-vinyl-pyrrolidone, 4,5-dimethyl-1-vinyl-pyrrolidone,
5,5-dimethyl-1-vinyl-pyrrolidone,
3,3,5-trimethyl-1-vinyl-pyrrolidone, 4-ethyl-1-vinyl-pyrrolidone,
5-methyl-5-ethyl-1-vinyl-pyrrolidone and
3,4,5-trimethyl-1-vinyl-pyrrolid- one; vinyl pyrroles; vinyl
anilines; and vinyl piperidines.
[0052] The substituted ethylene monomers useful as unsaturated
monomers is in the present invention include, but are not limited
to: vinyl acetate, vinyl formamide, vinyl chloride, vinyl fluoride,
vinyl bromide, vinylidene chloride, vinylidene fluoride, vinylidene
bromide and itaconic anhydride.
[0053] Suitable cyclic olefin monomers useful in the present
invention are (C.sub.5-C.sub.10)cyclic olefins, such as
cyclopentene, cyclopentadiene, dicylopentene, cyclohexene,
cyclohexadiene, cycloheptene, cycloheptadiene, cyclooctene,
cyclooctadiene, norbomene, maleic anhydride and the like. Suitable
substituted cyclic olefin monomers include, but are not limited to,
cyclic olefins having one or more substituent groups selected from
hydroxy, aryloxy, halo, (C.sub.1-C.sub.12)alkyl,
(C.sub.1-C.sub.12)haloalkyl, (C.sub.1-C.sub.12)hydroxyalkyl,
(C.sub.1-Cl.sub.2)halohydroxyalkyl such as
(CH.sub.12).sub.n'C(CF.sub.3).- sub.2OH where n'=0 to 4,
(C.sub.1-C.sub.12)alkoxy, thio, amino, (C.sub.1-C.sub.6)alkylamino,
(C.sub.1-C.sub.6)dialkylamino, (C.sub.1-C.sub.12)alkylthio,
carbo(C.sub.1-C.sub.20)alkoxy, carbo(C.sub.1-C.sub.20)haloalkoxy,
(C.sub.1-C.sub.12)acyl,
(C.sub.1-C.sub.6)alkylcarbonyl(C.sub.1-C.sub.6)alkyl, and the like.
Particularly suitable substituted cyclic olefins include maleic
anhydride and cyclic olefins containing one or more of hydroxy,
aryloxy, (C.sub.1-C.sub.12)alkyl, (C.sub.1-C.sub.12)haloalkyl,
(C.sub.1-C.sub.12)hydroxyalkyl, (C.sub.1-C.sub.12)halohydroxyalkyl,
carbo(C.sub.1-C.sub.20)alkoxy, and
carbo(C.sub.1-C.sub.20)haloalkoxy. It will be appreciated by those
skilled in the art that the alkyl and alkoxy substituents may be
optionally substituted, such as with halogen, hydroxyl, cyano,
(C.sub.1-C.sub.6)alkoxyl, mercapto, (C.sub.1-C.sub.6)alkylthio,
amino, acid labile leaving group and the like.
[0054] Suitable carbo(C.sub.1-C.sub.20)alkoxy substituents include,
but are not limited to, those of the formula C(O)O--LG, wherein LG
is a leaving group having 4 or more carbon atoms with at least one
quaternary carbon atom bonded directly to the carboxyl group.
Suitable leaving groups include, but are not limited to, isobutyl,
2,3-dimethylbutyl, 2,3,4-trimethylpentyl and alicyclic leaving
groups. Suitable alicyclic leaving groups include adamantyl,
methyladamantyl, ethyladamantyl, methylnorbomyl, ethylnorbomyl,
ethyltrimethylnorbomyl, and the like. Particularly useful alicyclic
leaving groups are those of Formulae IVa-IVd. 7
[0055] Other particularly useful cyclic olefin monomer substituents
include, but are not limited to, Ar--O--LG and
(CH.sub.2).sub.n'C(CF.sub.- 3).sub.2O--LG where n'=0 to 4, wherein
LG is as described above. It is preferred that the aryl group is
phenyl.
[0056] Suitable ethylenically unsaturated cyclic olefins having one
or more hydroxy groups include, but are not limited to, norbornenyl
alcohols of Formula (V) 8
[0057] wherein R.sup.1 , R.sup.2 and R.sup.3 are independently
hydrogen and (C.sub.1-C.sub.8)alkyl and wherein R.sup.1 and R.sup.3
may be joined to form a 5- to 7-member fused ring. It is preferred
that R.sup.1 and R.sup.3 are independently selected from hydrogen
or (C.sub.1-C.sub.8)alkyl, R.sup.2=cyclohexyl or cyclopentyl, and
R.sup.2 and R.sup.3 may be joined to form a 5- to 7-member fused
ring. It is further preferred that R.sup.1 is hydrogen or methyl.
Particularly useful norbornenyl alcohols are those of the Formulae
Va-Vc. 9
[0058] The spirocyclic polymers of the present invention may be
prepared by a variety of methods, such as free-radical
polymerization and metal catalyzed polymerization. Any catalyst is
suitable for use in the present invetion as long as it catalyzes
the polymerization of the double bond of the spirocyclic olefinic
monomers without substantially openi ng the rings of the
spirocyclic monomer. Metal catalyzed polymerizations are preferred.
Suitable free-radical polymerization catalysts include, but are not
limited to: hydrogen peroxide, tert-butyl hydroperoxide, sodium
persulfate, potassium persulfate, lithium persulfate; and the like.
Such free-radical polymerization conditions will be clear to those
skilled in the art.
[0059] It will be appreciated by those skilled in the art that more
than one metal catalyst may be used in the polymerizations of the
present invention. Suitable metal polymerization catalysts include,
but are not limited to, palladium(II) catalysts, such as palladium
dihalide, nonionic palladium(II)-halide complexes,
(Pd(RCN).sub.4)(BF.sub.4).sub.2, where R is (C.sub.1-C.sub.4)alkyl,
palladium(II)-alkyl complexes, and (.eta..sup.3-allyl)palladium(II)
compounds with weakly coordinating counterions. Preferred
palladium(II) catalysts are (Pd(RCN).sub.4)(BF.sub.4).sub.2, where
R is (C.sub.1-C.sub.4)alkyl, (.eta..sup.3-allyl)palladium(II)
compounds with weakly coordinating counterions, and mixtures
thereof. Particularly useful palladium(ll) catalysts include, but
are not limited to: (Pd(CH.sub.3CN).sub.4)(BF.sub.- 4).sub.2,
(Pd(C.sub.2H.sub.5CN).sub.4)(BF.sub.4).sub.2,
(.eta..sup.3-allyl)Pd(BF.sub.4), ((.eta..sup.3-allyl)PdCl).sub.2,
(.eta..sup.3-allyl)Pd(SbF.sub.6), and mixtures of
(.eta..sup.3-allyl)Pd(B- F.sub.4) and
(.eta..sup.3-allyl)Pd(SbF.sub.6). Such catalysts are generally
known, see, for example, Mathew et al., (.eta..sup.3-Allyl)pall-
adium(II) and Palladium(II) Nitrile Catalysts for the Addition
Polymerization of Norbornene Derivatives with Functional Groups,
Macromolecules, vol. 29, pages 2755-2763, 1996, herein incorporated
by reference to the extent it teaches the preparation and use of
such catalysts.
[0060] Other suitable metal polymerization catalysts include
nickel(II) catalysts having as ligands at least one of
salicylaldimine or substituted salicylaldimine and at least one of
acetonitrile or a phosphine, such as triphenylphosphine. Suitable
substituted salicylaldimine ligands include those substituted in
the ortho position to the oxygen with a bulky group, such as
phenyl, substituted phenyl, anthracene, substituted anthracene,
triphenylmethyl, meta-terphenyl and the like. Suitable catalysts
are those disclosed in Younkin et al., Neutral, Single-Component
Nickel (II) Polyolefin Catalysts that Tolerate Heteroatoms,
Science, vol. 287, pp 460-462, Jan. 21, 2000.
[0061] The ratio of monomer to metal catalyst in the polymerization
reaction of the present invention can range from about 5000:1 to
about 25:1, preferably from 1000:1 to 50:1, and more preferably
from 100:1 to 50:1. The polymerization reaction using this catalyst
can be run in a hydrocarbon solvent, such as cyclohexane, toluene,
benzene, nitrobenzene, chlorobenzene, nitromethane, dichloromethane
and mixtures thereof. A particularly useful solvent mixture is
nitrobenzene and dichlorobenzene in a 4:1 ratio. The polymerization
reactions using palladium(II) catalysts can be carried out at a
temperature in the range of from about 0.degree. to about
70.degree. C. It is preferred that the polymerization reaction is
carried out at a temperature of 10.degree. to 50.degree. C., and
more preferably 20.degree. to 40.degree. C. The yields for the
polymerizations are typically in the range of 25 to 100%.
[0062] The spirocyclic polymers of the present invention may be
used in any application where cyclic polymers may be useful. The
spirocyclic polymers of the present invention are particularly
useful in electronics applications, such as, but not limited to,
photoresist compositions, antireflective coating compositions,
soldermasks, dielectrics, and the like. Spirocyclic polymers of the
present invention containing as polymerized units one or more
spirocyclic olefin monomers containing one or more electron
withdrawing groups are particularly suitable for use as resin
binders in photoresist compositions. When used in photoresist
compositions, such spirocyclic polymers of the present invention
show reduced swelling and improved adhesion over known photoresist
compositions.
[0063] Particularly suitable spirocyclic polymers of the present
invention for use in photoresist compositions include those of
Formula Via and VIb 10
[0064] wherein Z.dbd.CH.sub.2, C(O), C(S), O or S; X and Y are
independently selected from CH.sub.2, C(O), C(S), O or NR.sup.2;
R.sup.2.dbd.(C.sub.1-C.sub.8)alkyl and substituted
(C.sub.1-C.sub.8)alkyl; R.sup.3.dbd.C(O)O(CH.sub.2).sub.qOH, H and
C(O)OR.sup.4; R.sup.4.dbd.(C.sub.1-C.sub.24)alkyl and H; J=C(O)O--,
Ar--O-- and (CH.sub.2).sub.n'C(CF.sub.3).sub.2--O--; LG is a
leaving group having 4 or more carbon atoms with at least one
quaternary carbon atom bonded directly to the carboxyl group; q is
an integer from 0 to 20; n'=0 to 4; r is 10 to 60 percent by weight
of the monomer unit, based on the total weight of the monomers; r'
is 10 to 80 percent by weight of the monomer unit, based on the
total weight of the monomers; t is 10 to 90 percent by weight of
the monomer unit, based on the total weight of the monomers; t' is
20 to 90 percent by weight of the monomer unit, based on the total
weight of the monomers; and p is 0 to 80 percent by weight of the
monomer unit, based on the total weight of the monomers. It is
preferred that the t+p is in the range of 20 to 90 percent by
Weight based on the total weight of the monomers, and more
preferably in the range of 60 to 90 percent by weight.
[0065] Other particularly suitable spirocyclic polymers of the
present invention, particularly for use in photoresist systems,
include as polymerized units one or more spirocyclic olefin
monomers of the present invention, maleic anhydride, one or more
cyclic olefin monomers having as a substituent a leaving group as
described herein and optionally one or more other monomers.
Suitable optional monomers in these polymers include, but are not
limited to, norbornene, itaconic anhydride, (meth)acrylate esters
and the like.
[0066] Other particularly suitable spirocyclic polymers of the
present invention for use in photoresist compositions are those
containing as polymerized units one or more spriocyclic olefin
monomers of Formulae VII and VIII 11
[0067] wherein R.sup.5.dbd.(C.sub.1-C.sub.24)alkyl and v is an
integer between 1 and 4. It is preferred that
R.sup.5.dbd.(C.sub.1-C.sub.6)alkyl, and more preferably
(C.sub.1-C.sub.4)alkyl. While not intending to be bound by theory,
it is believed that in certain cases, such as when v is 3 or
greater, such spirocyclic olefin monomers may ring open in the
presence of an acid to yield a norbomenyl compound containing as
pendant groups both a carboxylic acid and an alkene. Thus, such
spirocyclic monomer units, when polymerized into a polymer, may
also ring open in the presence of an acid. Such ring opening
affords a cyclic polymer backbone having carboxylic acid
functionality and an alkenyl group without the loss of any
significant mass. Thus, not only can an acid functionality can be
introduced into a cyclic polymer backbone with fewer reaction steps
than known methods, but the resulting spirocyclic polymers show
mass persistence, that is, they do not significantly shrink.
Spirocyclic polymers containing as polymerized units one or more
7-membered or higher-membered spirocyclic olefin monomers are thus
particularly useful in photoresist compositions.
[0068] The photoresist compositions of the present invention
include one or more photoactive components, one or more spirocyclic
resin binders of the present invention, and optionally one or more
additives. The photoactive components useful in the present
invention are typically photoacid or photobase generators, and
preferably photoacid generators.
[0069] The photoacid generators useful in the present invention are
any compounds which liberate acid upon exposure to light, typically
at a wavelength of about 320 to 420 nanometers, however other
wavelengths may be suitable. Suitable photoacid generators include
halogenated triazines, onium salts, sulfonated esters and
halogenated sulfonyloxy dicarboximides.
[0070] Particularly useful halogenated triazines include
halomethyl-s-triazines. Suitable halogenated triazines include for
example,
2-[1-(3,4-benzodioxolyl)]-4,6-bis(trichloromethyl)-1,2,5-triazin-
e,
2-[1-(2,3-benzodioxolyl)]-4,6-bis(trichloromethyl)-1,3,5-triazine,
2-[1-(3,4-benzodioxolyl)]-4,6-bis(tribromomethyl)-1,3,5-triazine,
2-[1-(2,3-benzodioxolyl)]-4,6-bis(tribromomethyl)- 1,3,5-triazine,
2-(2-furfylethylidene)-4,6-bis(trichloromethyl)-1,3,5-triazine,
2-[2-(5-methylfuryl)ethylidene]-4,6-bis(trichloromethyl)-1,3,5-triazine,
2-[2-(4-methylfuryl)ethylidene]-4,6-bis(trichloromethyl)-1,3,5-triazine,
2-[2-(3-methylfuryl)ethylidene]-4,6-bis-(trichloromethyl)-1,3,5-triazine,
2-[2-(4,5-dimethylfuryl)ethylidenie-4,6-bis(trichloromethyl)-1,3,5-triazi-
ne, 2-[2-(
5-methoxyfuryl)ethylidene]-4,6-bis(trichloromethyl)-1,3,5-triaz-
ine,
2-[2-(4-methoxyfuryl)ethylidene]-4,6-bis(trichloromethyl)-1,3,5-triaz-
ine, 2-[2-(3-methoxyfuryl)ethylidene]-4,6-bis
(trichloromethyl)-1,3,5-tria- zine,
2-[2-(4,5-dimethoxy-furyl)ethylidene]-4,6-bis(trichloromethyl)-1,3,5-
-triazine,
2-(2-furfylethylidene)-4,6-bis(tribromomethyl)-1,3,5-triazine,
2-[2-(5-methylfuryl)ethylidene]-4,6-bis(tribromomethyl)-1,3,5-triazine,
2-[2-(4-methylfuryl)-ethylidene]-4,6-bis(tribromomethyl)-1,3,5-triazine,
2-[2-(3-methylfuryl)ethylidene]-4,6-bis(tribromomethyl)-1,3,5-triazine,
2-[2-(4,5-dimethoxyfuryl)ethylidene]-4,6-bis(tribromomethyl)-1,3,5-triazi-
ne,
2-[2-(5-methoxyfuryl)ethylidene]-4,6-bis(tribromomethyl)-1,3,5-triazin-
e, 2-[2-(4-methoxyfuryl)ethylidene]-4,6-bis (tribromomethyl)-1,3
,5-triazine,
2-[2-(3-methoxyfuryl)ethylidene]-4,6-bis(tribromomethyl)-1,3-
,5-triazine,
2-[2-(4,5-dimethoxyfuryl)ethylidene]-4,6-bis(tribromomethyl)--
1,3,5-triazine, 2,4,6-tris-(trichloromethyl)-1,3,5-triazine,
2,4,6-tris-(tribromomethyl)-1,3,5-triazine,
2-phenyl-4,6-bis(trichloromet- hyl)-1,3,5-triazine,
2-phenyl-4,6-bis(tribromomethyl)-1,3,5-triazine,
2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-1,3,5-triazine,
2-(4-methoxyphenyl)-4,6-bis(tribromomethyl)-1,3,5-triazine, 2-(1
-naphthyl)-4,6-bis(trichloromethyl)-1,3,5-triazine,
2-(1-naphthyl)-4,6-bis(tribromomethyl)-1,3,5-triazine,
2-(4-methoxy-1-naphthyl)-4,6-bis(trichloromethyl)-1,3,5-triazine,
2-(4-methoxy-1-naphthyl)-4,6-bis(tribromomethyl)-1,3,5-triazine,
2-(4-chlorophenyl)-4,6-bis(tribromomethyl)-1,3,5-triazine,
2-styryl-4,6-bis(trichloromethyl)-1,3,5-triazine,
2-styryl-4,6-bis(tribro- momethyl)-1,3,5-triazine,
2-(4-methoxystyryl)-4,6-bis(trichloromethyl)-1,3- ,5-triazine,
2-(4-methoxystyryl)-4,6-bis(tribromomethyl)-1,3,5-triazine,
2-(3,4,5-trimethoxystyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine,
2-(3,4,5-trimethoxystyryl)-4,6-bis(tribromomethyl)-1,3,5-triazine,
2-(3-chloro-1-phenyl)-4,6-bis(trichloromethyl)-1,3,5-triazine,
2-(3-chlorophenyl)-4,6-bis(tribromomethyl)-1,3,5-triazine and the
like. Other triazine type photoacid generators useful in the
present invention are disclosed in U.S. Pat. No. 5,366,846, herein
incorporated by reference.
[0071] The s-triazine compounds are condensation reaction products
of certain methyl-halomethyl-s-triazines and certain aldehydes or
aldehyde derivatives. Such s-triazine compounds may be prepared
according to the procedures disclosed in U.S. Pat. No. 3,954,475
and Wakabayashi et al., Bulletin of the Chemical Society of Japan,
42, 2924-30 (1969).
[0072] Onium salts with weakly nucleophilic anions are particularly
suitable for use as photoacid generators in the present invention.
Examples of such anions are the halogen complex anions of divalent
to heptavalent metals or non-metals, for example, antimony, tin,
iron, bismuth, aluminum, gallium, indium, titanium, zirconium,
scandium, chromium, hafnium, copper, boron, phosphorus and arsenic.
Examples of suitable onium salts include, but are not limited to:
diaryl-diazonium salts and onium salts of group VA and B, IIA and B
and I of the Periodic Table, for example, halonium salts,
quaternary ammonium, phosphonium and arsonium salts, aromatic
sulfonium salts and sulfoxonium salts or selenium salts. Examples
of suitable onium are disclosed in U.S. Pat. Nos. 4,442,197;
4,603,101; and 4,624,912, all incorporated herein by reference.
[0073] The sulfonated esters useful as photoacid generators in the
present invention include sulfonyloxy ketones. Suitable sulfonated
esters include, but are not limited to: benzoin tosylate,
t-butylphenyl alpha-(p-toluenesulfonyloxy)-acetate, and t-butyl
alpha-(p-toluenesulfony- loxy)-acetate. Such sulfonated esters are
disclosed in the Journal of Photopolymer Science and Technology,
vol. 4, No. 3,337-340 (1991), incorporated herein by reference.
[0074] Suitable halogenated sulfonyloxy dicarboximides useful as
photoacid generators in the present invention include, but are not
limnited to:
1(((trifluoromethyl)sulfonyl)oxy)-1H-pyrrole-2,5-dione;
N-((perfluorooctanesulfonyl)oxy)-5-norbornene-2,3-dicarboximide;
1-(((trifluoromethyl)sulfonyl)oxy)-2,5-pyrrolidinedione;
3a,4,7,7a-tetrahydro-2-(((trifluoromethyl)sulfonyl)oxy)-4,7-methano-1H-is-
oindole-1,3 (2H)-dione;
2-(((trifluoromethyl)sulfonyl)oxy)-1H-benz(f)isoin-
dole-1,3(2H)-dione;
3,4-dimnethyl-1-(((trifluoromethyl)sulfonyl)oxy)-1H-py-
rrole-2,5-dione;
2-(((trifluoromethyl)sulfonyl)oxy)-1H-isoindole-1,3(2H)-d- ione;
2-(((trifluoromethyl)sulfonyl)oxy)-1H-benz(de)isoquinoline-1,3(2H)-d-
ione;
4,5,6,7-tetrahydro-2-(((trifluoromethyl)sulfonyl)oxy)-1H-isoindole-1-
,3(2H)-dione;
3a,4,7,7a-tetrahydro-2-(((trifluoromethyl)sulfonyl)oxy)-4,7--
epoxy-1H-isoindole-1,3(2H)-dione;
2,6-bis-(((trifluoromethyl)sulfonyl)oxy)-
-benzo(1,2-c:4,5-c')dipyrrole-1,3,5,7(2H,6H)-tetrone;
hexahydro-2,6-bis-(((trifluoromethyl)sulfonyl)oxy)-4,9-methano-1H-pyrrolo-
(4,4-g)isoquinoline-1,3,5,7(2H,3aH,6H)-tetrone;
1,8,8-trimethyl-3-(((trifl-
uoromethyl)sulfonyl)oxy)-3-azabicyclo(3.2.1)octane-2,4-dione;
4,7-dihydro-2--(((trifluoromethyl)sulfonyl)oxy)-4,7-epoxy-1H-isoindole-1,-
3(2H)-dione;
3-(1-naphthalenyl)-4-phenyl-1--(((trifluoromethyl)sulfonyl)ox-
y)-1H-pyrrole-2,5-dione;
3,4-diphenyl-1--(((trifluoromethyl)sulfonyl)oxy)--
1H-pyrrole-2,5-dione;
5,5'-(2,2,2-trifluoro-1-(triflluoromethyl)ethylidene-
)bis(2-(((trifluoromethyl)sulfonyl)oxy)-1H-isoindole-1,3(2H)-dione;
tetrahydro-4-(((trifluoromethyl)sulfonyl)oxy)-2,6-methano-2H-oxireno(f)is-
oindole-3,5(1 aH,4H)-dione;
5,5'-oxybis-2-(((trifluoromethyl)sulfonyl)oxy)-
-1H-isoindole-1,3(2H)-dione;
4-methyl-2-(((trifluoromethyl)sulfonyl)oxy)-1-
H-isoindole-1,3(2H)-dione;
3,3,4,4-tetramethyl-1-(((trifluoromethyl)sulfon-
yl)oxy)-2,5-pyrrolidinedione and mixtures thereof. It is preferred
that the halogenated sulfonyloxy dicarboximides comprise one or
more of 1(((trifluoromethyl)sulfonyl)oxy)-1H-pyrrole-2,5-dione;
N-((perfluorooctanesulfonyl)oxy)-5-norbornene-2,3-dicarboximide;
and 1-(((trifluoromethyl)sulfonyl)oxy)-2,5-pyrrolidinedione, and
more preferably
N-((perfluorooctanesulfonyl)oxy)-5-norbornene-2,3-dicarboximid-
e.
[0075] The photoactive components are typically added to
photoresist compositions in an amount sufficient to generate a
latent image in a coating layer of resist material upon exposure to
activating radiation. When the photoactive component is a photoacid
generator, the amount is typically in the range of 0.1 to 10
percent by weight, based on the weight of the resin, and preferably
1 to 8 percent by weight. It will be appreciated by those skilled
in that art that more than one photoacid generators may be used
advantageously in the photoresist compositions of the present
invention.
[0076] Any spirocyclic polymers of the present invention may be
advantageously used as the resin binders in the photoresist
compositions of the present invention. It will appreciated by those
skilled in the art that more than one resin binder may be used in
the photoresist compositions of the present invention, including
more than one spirocyclic resin binder. Thus, the spirocyclic resin
binders of the present invention may be advantageously combined
with one or more other resin binders.
[0077] The optional additives that may be used in the photoresist
compositions of the present invention include, but are not limited
to: anti-striation agents, plasticizers, speed enhancers, fillers,
dyes and the like. Such optional additives will be present in
relatively minor concentrations in a photoresist composition except
for fillers and dyes which may be used in relatively large
concentrations, e.g. in amounts of from about 5 to 30 percent by
weight, based on the total weight of the composition's dry
components.
[0078] The photoresist compositions of the present invention may be
readily prepared by those skilled in the art. For example, a
photoresist composition of the invention can be prepared by
dissolving the components of the photoresist in a suitable solvent.
Such suitable solvents include, but are not limited to: ethyl
lactate, ethylene glycol monomethyl ether, ethylene glycol
monomethyl ether acetate, propylene glycol monomethyl ether,
propylene glycol monomethyl ether acetate, 3-ethoxyethyl
propionate, 2-heptanone, .gamma.-butyrolactone, and mixtures
thereof. When the resin binder is a spirocyclic lactone polymer, it
is preferred that the solvent comprises .gamma.-butyrolactone, and
more preferably the solvent is a mixture of .gamma.-butyrolactone
and 2-heptanone. Thus, it is preferred that photoresist
compositions comprising spirocyclic resin binders including as
polymerized units spirocyclic olefin monomers of Formula I, and
preferably those of Formulae VII or VIII, contain
.gamma.-butyrolactone.
[0079] Typically, the solids content of the photoresist composition
varies from about 5 to about 35 percent by weight, based on the
total weight of the composition. The resin binder and photoacid
generators should be present in amounts sufficient to provide a
film coating layer and formation of good quality latent and relief
images.
[0080] Such photoresist compositions may be applied to a substrate
by any known means, such as spinning, dipping, roller coating and
the like. When the compositions are applied by spin coating, the
solids content of the coating solution can be adjusted to provide a
desired film thickness based upon the specific spinning equipment
utilized, the viscosity of the solution, the speed of the spinner
and the amount of time allowed for spinning.
[0081] Photoresist compositions including the spirocyclic polymers
of the present invention are useful in all applications where
photoresists are typically used. For example, the compositions may
be applied over silicon wafers or silicon wafers coated with
silicon dioxide for the production of microprocessors and other
integrated circuit components. Aluminum-aluminum oxide, gallium
arsenide, ceramic, quartz, copper, glass and the like are also
suitable employed as substrates for the photoresist compsitions of
the invention.
[0082] Once the photoresist composition is coated on a substrate
surface, it is dried by heating to remove any solvent. It is
preferably dried until the coating is tack free. Thereafter, it is
imaged through a mask in a conventional manner. The exposure is
sufficient to effectively activate the photoacid component of the
photoresist to produce a patterned image in the resist coating
layer, and more specifically, the exposure energy typically ranges
from about 1 to 100 mJ/cm.sup.2, dependent upon the exposure tool
and the components of the photoresist composition.
[0083] The photoresist compositions of the present invention are
preferably activated by a short exposure wavelength, particularly a
sub-300 nm, such as UV, and more preferably a sub-200 nm exposure
wavelength. Particularly preferred wavelengths include 248, 193,
157 nm and 11-15 nm. However, the photoresist compositions of the
present invention may be used at higher wavelengths, such as, but
not limited to, visible, e-beam and x-ray.
[0084] Following exposure, the film layer of the composition is
preferably baked at temperatures ranging from about 70.degree. C.
to 160.degree. C. Thereafter, the film is developed. The exposed
resist film is rendered positive working by employing a polar
developer, preferably an aqueous based developer, such as
quartemary ammonium hydroxide solutions, such as tetra-alkyl
ammonium hydroxide, preferably a 0.26 N tetramethylammonium
hydroxide; various amine solutions, such as ethylamine,
n-propylamine, diethylamine, triethylamine or methyl diethylamine;
alcohol amines, such as diethanolamine, triethanolamine; cyclic
amines, such as pyrrole, pyridine, and the like. One skilled in the
art will appreciate which development procedures should be used for
a given system.
[0085] After development of the photoresist coating, the developed
substrate may be selectively processed on those areas bared of
resist, for example, by chemically etching or plating substrate
areas bared of resist in accordance with procedures known in the
art. For the manufacture of microelectronic substrates, e.g. the
manufacture of silicon dioxide wafers, suitable etchants include,
but are not limited to, a gas etchant, such as a chlorine- or
fluorine-based etchant, such as Cl.sub.2 or CF.sub.4/CHF.sub.3
etchant applied as a plasma stream. After such processing, the
resist may be removed from the processed substrate using any
stripping procedures known in the art.
[0086] The following examples are intended to illustrate further
various aspects of the present invention, but are not intended to
limit the scope of the invention in any aspect.
EXAMPLE 1
[0087] Norbomene butyrolactone (or 4',5'-dihydro-(1a,2a,4a)-
spiro[bicyclo[2.2.1 ]hept-5-ene-2,3'(2'H)-furan]-2'-one) was
prepared as follows. Methylene butyrolactone was dissolved in
dichloromethane and freshly cracked cyclopentadiene was added. The
reaction mixture was stirred at room temperature for 3 hours,
heated to 40.degree. C. and held at 40.degree. C. overnight. The
reaction mixture was then slowly cooled to room temperature. The
methylene chloride was removed under reduced pressure, leaving an
oil. The crude oil was then distilled under reduced pressure to
afford pure product.
EXAMPLE 2
[0088] Norbornene valerolactone was prepared as follows. A solution
of valerolactone (50.1 g) in 150 mL of anhydrous THF was placed in
a three-neck-bottomed flask at -78.degree. C. (dry ice/acetone
bath). To it, solution of lithium dimethylamine ("LDA") (250 mL,
2M) in 250 mL anhydrous THF was added dropwise. The reaction
mixture was stirred at this temperature for 4 hours. Then, the
thermal cracking of paraformaldehyde (36.94 g, excess) was bubbled
into the reaction mixture. After the paraformaldehyde was all
cracked, the reaction mixture was stirred overnight and allowed to
gradually warm to room temperature. Then, the solvent was removed
by rotary pump and the residue was added 500 mL dichloromethane and
washed with NaHCO.sub.3 (aq, sat.) and water several times
(3.times.500 mL). The organic solvent was dried over MgSO.sub.4 and
then removed by rotary pump. The desired product,
methylene-valerolactone, was distilled under vacuum
(135-140.degree. C./8 mm Hg).
[0089] The methylene-valerolactone was then dissolved in
dichloromethane and freshly cracked cyclopentadiene was added. The
reaction mixture was stirred at room temperature for 3 hours, then
heated to 40.degree. C., and held at 40.degree. C. overnight. The
reaction mixture was then slowly cooled to room temperature. The
dichloromethane was removed under reduced pressure, leaving an oil.
The crude oil was then distilled under reduced pressure to afford
pure product.
EXAMPLE 3
[0090] To a 50 ml glass vial equipped with a Teflon coated stir bar
is added 2.64 g (13.6 mmol) of 5-norbornenecarboxylic acid
tert-butyl ester, 0.952 g (5.34 mmol) of
spiro[bicyclo[2.2.1]hept-5-ene-2,3'(2'H)-furan]-2'- ,5'(4'H)-dione,
as shown by the following formula 12
[0091] together with 50 ml of freshly distilled dichloroethane. The
solution is degassed under an argon atmosphere. A 10 ml glass vial
equipped with a Teflon coated stir bar is then charged with 0.0365
g (0.1 mmol) of h.sup.3-allylpalladium chloride dimer and 2 ml of
dichloroethane. Another 10 ml glass vial is charged with 0.0195 g
(0.1 mmol) of silver tetrafluoroborate and 2 ml of dichloroethane.
The catalyst solution is then prepared by mixing the allylpalladium
chloride dimer solution with silver tetrafluoroborate solution
inside a dry box. Silver chloride salt will immediately
precipitate, which is then filtered, and a clear yellow solution is
obtained. This active yellow catalyst solution is added to the
monomer solution via a syringe and the reaction mixture is allowed
to stir for 20 hours at 60.degree. C. Solids that form typically
precipitate in the solution. The solution is cooled, concentrated
in a rotary-evaporator, and precipitated into hexane to obtain the
polymer.
EXAMPLE 4
[0092] The polymer from Example 3 (1.4 g) is placed in a bottle,
together with 0.0895 g of triphenyl sulfonium trifluoromethane
sulfonate (TPS-Triflate), 0.00165 g of
1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 6.11 g of methyl amyl
ketone and 3.05 g of propylene glycol methyl ether acetate. The
mixture is then stirred on a rolling mill until all solids
completely dissolve. The solution is then filtered through a 0.05
mm porous filter into a clean bottle. The resulting resist is spun
on a silicon wafer, baked on a hot plate at 135.degree. C. for 60
sec, exposed on an ISI 193 nm step-and-repeat printer,
post-exposure baked at 155.degree. C. for 60 sec and then developed
in an aqueous solution of 2.38% tetramethylammonium hydroxide.
Typically, adhesion is improved and little or no swelling of the
resist features is observed.
EXAMPLE 5
[0093] To a 50 ml glass vial equipped with a Teflon coated stir bar
is added 1.943 g (10.0 mmol) of TBN-CA, 1.64 g (10.0 mmol) of
4',5'-dihydro-(1a,2a,4a)-
spiro[bicyclo[2.2.1]hept-5-ene-2,3'(2'H)-furan]- -2'-one, as shown
by the following formula 13
[0094] together with 50 ml of freshly distilled dichloroethane. The
solution is degassed under an argon atmosphere. A 10 ml glass vial
is equipped with a Teflon coated stir bar and then is charged with
0.0365 g (0.1 mmol) of .eta..sup.3-allylpalladium chloride dimer
and 2 mL of dichloroethane. Into another 10 mL glass vial is
charged with 0.0195 g (0.1 mmol) of silver tetrafluoroborate and 2
mL of dichlorethane. The catalyst solution is prepared by mixing
the allylpalladium chloride dimer solution with silver
tetrafluoroborate solution inside a dry box. Silver chloride
immediately precipitates, and the mixture is then filtered, to
obtain a clear yellow solution. This active yellow catalyst
solution is added to the monomer solution via a syringe and the
reaction mixture is then allowed to stir for 20 hours at 60.degree.
C. Solids that form typically precipitate in the solution. The
solution is cooled, concentrated in a rotary-evaporator, and
precipitated into hexane to obtain the polymer.
EXAMPLE 6
[0095] The procedure of Example 4 is repeated except that 1.4 g of
the polymer from Example 5 is used and the solvent consists of 4.58
g g-butyrolactone and 4.58 g 2-heptanone. Typically, adhesion is
improved and little or no swelling of the resist features is
observed.
EXAMPLES 7-22
[0096] Polymers useful as photoresist binders are shown in the
following Table. Such polymers are prepared according to the
procedures described in Examples 3 or 5, as noted in the Table.
1TABLE Monomer 1 Monomer 2 Monomer 3 Polymer Example Mol % Mol %
Mol % Preparation 7 14 15 16 Example 5 33 33 33 8 17 18 19 Example
5 33 33 33 9 20 21 22 Example 5 33 33 33 10 23 24 -- Example 3 50
50 11 25 26 -- Example 3 50 50 12 27 -- 28 Example 3 50 50 13 29 --
30 Example 3 50 50 14 31 32 33 Example 5 33 33 33 15 34 35 --
Example 5 50 50 16 36 37 -- Example 5 40 60 17 38 39 -- Example 5
30 70 18 40 41 42 Example 5 30 40 30 19 43 44 45 Example 5 40 50 10
20 46 47 48 Example 5 30 50 20 21 49 50 51 Example 5 20 50 30 22 52
53 54 Example 5 30 40 30
EXAMPLE 23
[0097] The following polymer was prepared. 55
[0098] A mixture of norbornene ethyltricyclodecane carboxylate
(I15.16 g), maleic anhydride (6.60 g), norbornene-spiro-butylactone
(2.80 g), and dimethyl 2,2'-azobis(2-methylpropionate) (0.31 g, 1
mole % of total monomers) in 12.28 g ethyl acetate was placed in a
round-bottomed flask. After stirring for 5 minutes (until all
solids were dissolved), the flask was put into a pre-heated
70.degree. C. oil bath. The reaction mixture was stirred at this
temperature for 24 hours. After cooling, 25.0 g of tetrahydrofuran
was added. The polymer was isolated by precipitation into 1.5 L of
hexane/isopropanol (1/1, w/w.). The resulting suspension was
stirred for 120 minutes. The polymer was filtered off and washed
with an additional 200 mL of hexane. The polymer was dried in a
vacuum oven at 40.degree. C. overnight. The overall yield was
25%.
EXAMPLE 24
[0099] The polymer
norborene/(spiro-2-2-.alpha.-butyrolactone)-5-norborene-
/norbornene ethyl tricyclodecane carboxylate/maleic anhydride
(7.5/7.5/35/50 mol %) was prepared. 56
[0100] Into a 100 mL round bottom flask were added norbomnene 1.22
g (0.013 mol), (spiro-2-2-.alpha.-butyrolactone)-5-norborene 2.13
g(0.013 mol), maleic anhydride 8.86 g (0.086 mol), norbornene ethyl
tricyclodecane carboxylate 18.18 grams (0.060 moles), dimethyl
2,2'-azobis(2-methyipropionate) 0.4 g (0.0017 mol) and 15 g ethyl
acetate. A magnetic stir bar was added to the flask and the
solution was stirred for approximately 15 minutes to dissolve the
solids. Once all the solids were dissolved, the flask was placed in
a hot oil bath that was preheated to 80.degree. C. A condenser and
nitrogen line were attached on top and the reaction was allowed to
stir for 24 hours. After 24 hours the heat was removed and the
flask was allowed to cool to room temperature. After cooling, the
contents of the flask was precipitated into 1.5 L of
hexanes/isopropanol (50/50 w/w). The precipitated solution was
stirred for 1.5 hours and then the polymer was isolated via a glass
fritted funnel. The polymer was then dried for 4 hours in a hood
and then overnight in a vacuum oven at room temperature. This
reaction yielded 15 grams of polymer (50%).
EXAMPLE 25
[0101] Photoresists containing the polymers of Examples 7 to 22 are
prepared by according to Examples 4 or 6, except that the polymers
are taken up in .gamma.-butyrolactone.
* * * * *