U.S. patent application number 11/453030 was filed with the patent office on 2006-10-19 for novel ester compounds, polymers, resist compositions and patterning process.
Invention is credited to Koji Hasegawa, Takeshi Kinsho, Takeru Watanabe.
Application Number | 20060234160 11/453030 |
Document ID | / |
Family ID | 31973382 |
Filed Date | 2006-10-19 |
United States Patent
Application |
20060234160 |
Kind Code |
A1 |
Hasegawa; Koji ; et
al. |
October 19, 2006 |
Novel ester compounds, polymers, resist compositions and patterning
process
Abstract
Novel ester compounds having formula (1) wherein A.sup.1 is a
polymerizable functional group having a double bond, A.sup.2 is
furandiyl, tetrahydrofurandiyl or oxanorbornanediyl, R.sup.1 and
R.sup.2 each are a monovalent hydrocarbon group, or R.sup.1 and
R.sup.2 may bond together to form an aliphatic hydrocarbon ring
with the carbon atom, and R.sup.3 is hydrogen or a monovalent
hydrocarbon group which may contain a hetero atom are polymerizable
into polymers. Resist compositions comprising the polymers are
sensitive to high-energy radiation, have an improved sensitivity,
resolution, and etching resistance, and lend themselves to
micropatterning with electron beams or deep-UV rays. ##STR1##
Inventors: |
Hasegawa; Koji; (US)
; Kinsho; Takeshi; (US) ; Watanabe; Takeru;
(US) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Family ID: |
31973382 |
Appl. No.: |
11/453030 |
Filed: |
June 15, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10671948 |
Sep 29, 2003 |
|
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11453030 |
Jun 15, 2006 |
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Current U.S.
Class: |
430/270.1 |
Current CPC
Class: |
G03F 7/0392 20130101;
G03F 7/0395 20130101; G03F 7/0397 20130101; Y10S 430/111 20130101;
Y10S 430/106 20130101; C08F 20/30 20130101 |
Class at
Publication: |
430/270.1 |
International
Class: |
G03C 1/00 20060101
G03C001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 30, 2002 |
JP |
2002-285161 |
Claims
1. An ester compound having the general formula (1): ##STR59##
wherein A.sup.1 is a polymerizable functional group having a
carbon-to-carbon double bond, A.sup.2 is tetrahydrofurandiyl,
R.sup.1 and R.sup.2 bond together to form an aliphatic hydrocarbon
ring with the carbon atom to which they are bonded, and R.sup.3 is
hydrogen or a straight, branched, or cyclic monovalent hydrocarbon
group having 1 to 10 carbon atoms which may contain a hetero
atom.
2. A polymer comprising recurring units derived from the ester
compound of claim 1.
3. A polymer comprising recurring units of any one of the general
formulae (1b) and (1c): ##STR60## wherein A.sup.2 is a divalent
group selected from among furandiyl, and tetrahydrofurandiyl,
R.sup.1 and R.sup.2 bond together to form an aliphatic hydrocarbon
ring with the carbon atom to which they are bonded, R.sup.3 is
hydrogen or a straight, branched, or cyclic monovalent hydrocarbon
group having 1 to 10 carbon atoms which may contain a hetero atom,
and k.sup.1 is 0 or 1.
4. The polymer of claim 3, further comprising recurring units of
any one of the general formulae (M1) to (M13): ##STR61## ##STR62##
wherein R.sup.001 is hydrogen, methyl or CH.sub.2CO.sub.2R.sup.003;
R.sup.002 is hydrogen, methyl or CO.sub.2R.sup.003; R.sup.003 is a
straight, branched or cyclic alkyl group of 1 to 15 carbon atoms;
R.sup.004 is hydrogen or a monovalent hydrocarbon group of 1 to 15
carbon atoms having a carboxyl or hydroxyl group; at least one of
R.sup.005 to R.sup.008 represents a monovalent hydrocarbon group of
1 to 15 carbon atoms having a carboxyl or hydroxyl group while the
remaining R's independently represent hydrogen or a straight,
branched or cyclic alkyl group of 1 to 15 carbon atoms, or
R.sup.005 to R.sup.008, taken together, may form a ring, and in
that event, at least one of R.sup.005 to R.sup.008 is a divalent
hydrocarbon group of 1 to 15 carbon atoms having a carboxyl or
hydroxyl group, while the remaining R's are independently single
bonds or straight, branched or cyclic alkylene groups of 1 to 15
carbon atoms; R.sup.009 is a monovalent hydrocarbon group of 2 to
15 carbon atoms containing at least one partial structure selected
from among ether, aldehyde, ketone, ester, carbonate, acid
anhydride, amide and imide; at least one of R.sup.010 to R.sup.013
is a monovalent hydrocarbon group of 2 to 15 carbon atoms
containing at least one partial structure selected from among
ether, aldehyde, ketone, ester, carbonate, acid anhydride, amide
and imide, while the remaining R's are independently hydrogen or
straight, branched or cyclic alkyl groups of 1 to 15 carbon atoms,
or R.sup.010 to R.sup.013, taken together, may form a ring, and in
that event, at least one of R.sup.010 to R.sup.013 is a divalent
hydrocarbon group of 1 to 15 carbon atoms containing at least one
partial structure selected from among ether, aldehyde, ketone,
ester, carbonate, acid anhydride, amide and imide, while the
remaining R's are independently single bonds or straight, branched
or cyclic alkylene groups of 1 to 15 carbon atoms; R.sup.014 is a
polycyclic hydrocarbon group having 7 to 15 carbon atoms or an
alkyl group containing a polycyclic hydrocarbon group; R.sup.015 is
an acid labile group; X is CH.sub.2 or an oxygen atom or sulfur
atom; Y' is --O-- or --(NR.sup.f)--; R.sup.f is hydrogen atom or a
straight, branched or cyclic alkyl group of 1 to 15 carbon atoms;
and letter k is 0 or 1.
5. A resist composition comprising the polymer of claim 3.
6. A process for forming a resist pattern comprising the steps of:
applying the resist composition of claim 5 onto a substrate to form
a coating, heat treating the coating and then exposing it to
high-energy radiation or electron beams through a photomask, and
optionally heat treating the exposed coating and developing it with
a developer.
7. An ester compound having the general formula: ##STR63## wherein
A.sup.2 is tetrahydrofurandiyl, R.sup.1 and R.sup.2 bond together
to form an aliphatic hydrocarbon ring with the carbon atom to which
they are bonded, R.sup.3 is hydrogen or a straight, branched or
cyclic monovalent hydrocarbon group having 1 to 10 carbon atoms
which may contain a hetero atom, and R.sup.4 is hydrogen or
methyl.
8. A polymer comprising recurring units of the general formula
(1a): ##STR64## wherein A.sup.2 is a divalent group selected from
among furandiyl and tetrahydrofurandiyl, R.sup.1 and R.sup.2 bond
together to form an aliphatic hydrocarbon ring with the carbon atom
to which they are bonded, R.sup.3 is hydrogen or a straight,
branched or cyclic monovalent hydrocarbon group having 1 to 10
carbon atoms which may contain a hetero atom, and R.sup.4 is
hydrogen or methyl.
9. The polymer of claim 8, further comprising recurring units of
any one of the general formulae (M1) to (M13): ##STR65## ##STR66##
wherein R.sup.001 is hydrogen, methyl or CH.sub.2CO.sub.2R.sup.003;
R.sup.002 is hydrogen, methyl or CO.sub.2R.sup.003; R.sup.003 is a
straight, branched or cyclic alkyl group of 1 to 15 carbon atoms;
R.sup.004 is hydrogen or a monovalent hydrocarbon group of 1 to 15
carbon atoms having a carboxyl or hydroxyl group; at least one of
R.sup.005 to R.sup.008 represents a monovalent hydrocarbon group of
1 to 15 carbon atoms having a carboxyl or hydroxyl group while the
remaining R's independently represent hydrogen or a straight,
branched or cyclic alkyl group of 1 to 15 carbon atoms, or
R.sup.005 to R.sup.008, taken together, may form a ring, and in
that event, at least one of R.sup.005 to R.sup.008 is a divalent
hydrocarbon group of 1 to 15 carbon atoms having a carboxyl or
hydroxyl group, while the remaining R's are independently single
bonds or straight, branched or cyclic alkylene groups of 1 to 15
carbon atoms; R.sup.009 is a monovalent hydrocarbon group of 2 to
15 carbon atoms containing at least one partial structure selected
from among ether, aldehyde, ketone, ester, carbonate, acid
anhydride, amide and imide; at least one of R.sup.010 to R.sup.013
is a monovalent hydrocarbon group of 2 to 15 carbon atoms
containing at least one partial structure selected from among
ether, aldehyde, ketone, ester, carbonate, acid anhydride, amide
and imide, while the remaining R's are independently hydrogen or
straight, branched or cyclic alkyl groups of 1 to 15 carbon atoms,
or R.sup.010 to R.sup.013, taken together, may form a ring, and in
that event, at least one of R.sup.010 to R.sup.013 is a divalent
hydrocarbon group of 1 to 15 carbon atoms containing at least one
partial structure selected from among ether, aldehyde, ketone,
ester, carbonate, acid anhydride, amide and imide, while the
remaining R's are independently single bonds or straight, branched
or cyclic alkylene groups of 1 to 15 carbon atoms; R.sup.014 is a
polycyclic hydrocarbon group having 7 to 15 carbon atoms or an
alkyl group containing a polycyclic hydrocarbon group; R.sup.015 is
an acid labile group; X is CH.sub.2 or an oxygen atom or sulfur
atom; Y' is --O-- or --(NR.sup.f)--; R.sup.f is hydrogen atom or a
straight, branched or cyclic alkyl group of 1 to 15 carbon atoms;
and letter k is 0 or 1.
10. A resist composition comprising the polymer of claim 8.
11. A process for forming a resist pattern comprising the steps of:
applying the resist composition of claim 10 onto a substrate to
form a coating, heat treating the coating and then exposing it to
high-energy radiation or electron beams through a photomask, and
optionally heat treating the exposed coating and developing it with
a developer.
12. An ester compound selected from the group consisting of
compounds having any one of the following formulae: ##STR67##
##STR68## ##STR69## ##STR70##
13. A polymer comprising recurring units derived from the ester
compound of claim 12.
14. The polymer of claim 13, further comprising recurring units of
any one of the general formulae (M1) to (M13): ##STR71## ##STR72##
wherein R.sup.001 is hydrogen, methyl or CH.sub.2CO.sub.2R.sup.003;
R.sup.002 is hydrogen, methyl or CO.sub.2R.sup.003; R.sup.003 is a
straight, branched or cyclic alkyl group of 1 to 15 carbon atoms;
R.sup.004 is hydrogen or a monovalent hydrocarbon group of 1 to 15
carbon atoms having a carboxyl or hydroxyl group; at least one of
R.sup.005 to R.sup.008 represents a monovalent hydrocarbon group of
1 to 15 carbon atoms having a carboxyl or hydroxyl group while the
remaining R's independently represent hydrogen or a straight,
branched or cyclic alkyl group of 1 to 15 carbon atoms, or
R.sup.005 to R.sup.008, taken together, may form a ring, and in
that event, at least one of R.sup.005 to R.sup.008 is a divalent
hydrocarbon group of 1 to 15 carbon atoms having a carboxyl or
hydroxyl group, while the remaining R's are independently single
bonds or straight, branched or cyclic alkylene groups of 1 to 15
carbon atoms; R.sup.009 is a monovalent hydrocarbon group of 2 to
15 carbon atoms containing at least one partial structure selected
from among ether, aldehyde, ketone, ester, carbonate, acid
anhydride, amide and imide; at least one of R.sup.010 to R.sup.013
is a monovalent hydrocarbon group of 2 to 15 carbon atoms
containing at least one partial structure selected from among
ether, aldehyde, ketone, ester, carbonate, acid anhydride, amide
and imide, while the remaining R's are independently hydrogen or
straight, branched or cyclic alkyl groups of 1 to 15 carbon atoms,
or R.sup.010 to R.sup.013, taken together, may form a ring, and in
that event, at least one of R.sup.010 to R.sup.013 is a divalent
hydrocarbon group of 1 to 15 carbon atoms containing at least one
partial structure selected from among ether, aldehyde, ketone,
ester, carbonate, acid anhydride, amide and imide, while the
remaining R's are independently single bonds or straight, branched
or cyclic alkylene groups of 1 to 15 carbon atoms; R.sup.014 is a
polycyclic hydrocarbon group having 7 to 15 carbon atoms or an
alkyl group containing a polycyclic hydrocarbon group; R.sup.015 is
an acid labile group; X is CH.sub.2 or an oxygen atom or sulfur
atom; Y' is --O-- or --(NR.sup.f)--; R.sup.f is hydrogen atom or a
straight, branched or cyclic alkyl group of 1 to 15 carbon atoms;
and letter k is 0 or 1.
15. A resist composition comprising the polymer of claim 14.
16. A process for forming a resist pattern comprising the steps of:
applying the resist composition of claim 15 onto a substrate to
form a coating, heat treating the coating and then exposing it to
high-energy radiation or electron beams through a photomask, and
optionally heat treating the exposed coating and developing it with
a developer.
17. The ester compound of claim 1, wherein A.sup.1 is selected from
the group consisting of vinyl, allyl, 1-propenyl, isopropenyl, and
tetracyclo[4.4.0.1.sup.2,5.1.sup.7,10 ]dodecyl.
18. A polymer comprising recurring units derived from the ester
compound of claim 17.
19. A resist composition comprising the polymer of claim 18.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a 37 C.F.R. .sctn. 1.53(b)
divisional of U.S. application Ser. No. 10/671,948 filed Sep. 29,
2003, which in turn claims priority on Japanese Application No.
2002-285161 filed Sep. 30, 2002. The entire contents of each of
these applications is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to (1) a novel ester compound,
(2) a polymer comprising units of the ester compound which is
blended as a base resin to formulate a chemically amplified resist
composition suitable in the micropatterning technology, (3) a
resist composition comprising the polymer, and (4) a patterning
process using the resist composition.
[0004] 2. Prior Art
[0005] While a number of recent efforts are being made to achieve a
finer pattern rule in the drive for higher integration and
operating speeds in LSI devices, deep-ultraviolet lithography is
thought to hold particular promise as the next generation in
microfabrication technology. In particular, photolithography using
a KrF or ArF excimer laser as the light source is strongly desired
to reach the practical level as the micropatterning technique
capable of achieving a feature size of 0.3 .mu.m or less.
[0006] For resist materials for use with a KrF excimer lasers,
polyhydroxystyrene having a practical level of transmittance and
etching resistance is, in fact, a standard base resin. For resist
materials for use with ArF excimer lasers, polyacrylic or
polymethacrylic acid derivatives and polymers comprising
cycloaliphatic compounds in the backbone are under investigation.
In either case, the basic concept is that some or all of alkali
soluble sites of alkali soluble resin are protected with acid
labile or eliminatable groups. The overall performance of resist
material is adjusted by a choice from among a variety of acid
eliminatable protective groups.
[0007] Exemplary acid eliminatable protective groups include
tert-butoxycarbonyl (JP-B 2-27660), tert-butyl (JP-A 62-115440 and
J. Photopolym. Sci. Technol. 7 [3], 507 (1994)),
2-tetrahydropyranyl (JP-A 2-80515 and JP-A 5-88367), and
1-ethoxyethyl (JP-A 2-19847 and JP-A 4-215661). While it is desired
to achieve a finer pattern rule, none of these acid eliminatable
protective groups are deemed to exert satisfactory performance.
[0008] More particularly, tert-butoxycarbonyl and tert-butyl are
extremely less reactive with acids so that a substantial quantity
of energy radiation must be irradiated to generate a sufficient
amount of acid in order to establish a difference in rate of
dissolution before and after exposure. If a photoacid generator of
the strong acid type is used, the exposure can be reduced to a
relatively low level because reaction can proceed with a small
amount of acid generated. However, in this event, the deactivation
of the generated acid by air-borne basic substances has a
relatively large influence, giving rise to such problems as a T-top
pattern. On the other hand, 2-tetrahydropyranyl and 1-ethoxyethyl
are so reactive with acids that with the acid generated by
exposure, elimination reaction may randomly proceed without a need
for heat treatment, with the result that substantial dimensional
changes occur between exposure and heat treatment/ development.
Where these groups are used as protective groups for carboxylic
acid, they have a low inhibiting effect to alkali dissolution,
resulting in a high rate of dissolution in unexposed areas and film
thinning during development. If highly substituted polymers are
used to avoid such inconvenience, there results an extreme drop of
heat resistance. These resins fail to provide a difference in rate
of dissolution before and after exposure, resulting in resist
materials having a very low resolution.
[0009] For the above-described resist materials using
acid-eliminatable protective groups, there is a common problem of
line density dependency that when a pattern to be transferred
includes dense and sparse regions, it is impossible to produce the
desired pattern in both the dense and sparse regions at the same
exposure. More particularly, with respect to the formation of a
line-and-space pattern, for example, if solitary lines are formed
at an exposure that can resolve crowded lines with good size
control, they are finished to a line width less than the desired
size. Presumably this phenomenon is ascribable to the increased
diffusion length of acid generated upon exposure. There is a
tendency that the diffusion of the generated acid is enhanced as
the system becomes more hydrophobic. Since both (meth)acrylic
resins and cycloaliphatic backbone resins have increased their
carbon density in order to improve etching resistance, the
diffusion of the generated acid is more promoted as a result,
exaggerating line density dependency. Then at the very fine pattern
size for which an ArF excimer laser is actually used, a resist
material having substantial line density dependency cannot be used
in an industrially acceptable manner because solitary lines can
disappear. While a finer pattern rule is being demanded, there is a
need to have a resist material which is not only satisfactory in
sensitivity, resolution, and etching resistance, but also minimized
in line density dependency.
SUMMARY OF THE INVENTION
[0010] Therefore, an object of the present invention is to provide
(1) a novel ester compound capable of forming a polymer which is
effectively acid-decomposable and can control the diffusion of the
acid generated upon exposure, (2) a polymer which is blended as a
base resin to formulate a resist composition having a higher
sensitivity and resolution than conventional resist compositions as
well as minimized line density dependency, (3) a resist composition
comprising the polymer as a base resin, and (4) a patterning
process using the resist composition.
[0011] It has been found that ester compounds of the general
formula (1), shown below, can be prepared in high yields by a
simple method to be described later; that polymers obtained using
the ester compounds have high transparency at the exposure
wavelength of an excimer laser; that resist compositions comprising
the polymers as the base resin have a high sensitivity, high
resolution and minimized line density dependency; and that these
resist compositions lend themselves to precise micropatterning.
[0012] In a first aspect, the invention provides an ester compound
having the general formula (1). ##STR2## Herein A.sup.1 is a
polymerizable functional group having a carbon-to-carbon double
bond, A.sup.2 is a divalent group selected from among furandiyl,
tetrahydrofurandiyl and oxanorbornanediyl, R.sup.1 and R.sup.2 are
each independently a straight, branched or cyclic monovalent
hydrocarbon group having 1 to 10 carbon atoms, or R.sup.1 and
R.sup.2 may bond together to form an aliphatic hydrocarbon ring
with the carbon atom to which they are bonded, and R.sup.3 is
hydrogen or a straight, branched or cyclic monovalent hydrocarbon
group having 1 to 10 carbon atoms which may contain a hetero
atom.
[0013] In a preferred embodiment, the ester compound has the
general formula (2). ##STR3## Herein R.sup.1 and R.sup.2 are as
defined above, and R.sup.4 is hydrogen or methyl.
[0014] In another preferred embodiment, the ester compound has the
general formula (3). ##STR4## Herein R.sup.1, R.sup.2 and R.sup.4
are as defined above, and k.sup.1 is 0 or 1.
[0015] In a second aspect, the invention provides a polymer
comprising recurring units derived from the ester compound.
[0016] Another embodiment is a polymer comprising recurring units
of any one of the general formulae (1a) to (1c). ##STR5## Herein
A.sup.1 is a polymerizable functional group having a
carbon-to-carbon double bond, A.sup.2 is a divalent group selected
from among furandiyl, tetrahydrofurandiyl and oxanorbornanediyl,
R.sup.1 and R.sup.2 are each independently a straight, branched or
cyclic monovalent hydrocarbon group having 1 to 10 carbon atoms, or
R.sup.1 and R.sup.2 may bond together to form an aliphatic
hydrocarbon ring with the carbon atom to which they are bonded,
R.sup.3 is hydrogen or a straight, branched or cyclic monovalent
hydrocarbon group having 1 to 10 carbon atoms which may contain a
hetero atom, R.sup.4 is hydrogen or methyl, and k.sup.1 is 0 or
1.
[0017] The polymer may further comprise recurring units of any one
of the general formulae (M1) to (M13). ##STR6## ##STR7## Herein
R.sup.001 is hydrogen, methyl or CH.sub.2CO.sub.2R.sup.003;
R.sup.002 is hydrogen, methyl or CO.sub.2R.sup.003; R.sup.003 is a
straight, branched or cyclic alkyl group of 1 to 15 carbon atoms;
R.sup.004 is hydrogen or a monovalent hydrocarbon group of 1 to 15
carbon atoms having a carboxyl or hydroxyl group; at least one of
R.sup.005 to R.sup.008 represents a monovalent hydrocarbon group of
1 to 15 carbon atoms having a carboxyl or hydroxyl group while the
remaining R's independently represent hydrogen or a straight,
branched or cyclic alkyl group of 1 to 15 carbon atoms, or
R.sup.005 to R.sup.008, taken together, may form a ring, and in
that event, at least one of R.sup.005 to R.sup.008 is a divalent
hydrocarbon group of 1 to 15 carbon atoms having a carboxyl or
hydroxyl group, while the remaining R's are independently single
bonds or straight, branched or cyclic alkylene groups of 1 to 15
carbon atoms; R.sup.009 is a monovalent hydrocarbon group of 2 to
15 carbon atoms containing at least one partial structure selected
from among ether, aldehyde, ketone, ester, carbonate, acid
anhydride, amide and imide; at least one of R.sup.010 to R.sup.013
is a monovalent hydrocarbon group of 2 to 15 carbon atoms
containing at least one partial structure selected from among
ether, aldehyde, ketone, ester, carbonate, acid anhydride, amide
and imide, while the remaining R's are independently hydrogen or
straight, branched or cyclic alkyl groups of 1 to 15 carbon atoms,
or R.sup.010 to R.sup.013, taken together, may form a ring, and in
that event, at least one of R.sup.010 to R.sup.013 is a divalent
hydrocarbon group of 1 to 15 carbon atoms containing at least one
partial structure selected from among ether, aldehyde, ketone,
ester, carbonate, acid anhydride, amide and imide, while the
remaining R's are independently single bonds or straight, branched
or cyclic alkylene groups of 1 to 15 carbon atoms; R.sup.014 is a
polycyclic hydrocarbon group having 7 to 15 carbon atoms or an
alkyl group containing a polycyclic hydrocarbon group; R.sup.015 is
an acid labile group; X is CH.sub.2 or an oxygen atom or sulfur
atom; Y' is --O-- or --(NR.sup.f)--; R.sup.f is hydrogen atom or a
straight, branched or cyclic alkyl group of 1 to 15 carbon atoms;
and k is 0 or 1.
[0018] In a third aspect, the invention provides a resist
composition comprising the polymer defined above.
[0019] In a fourth aspect, the invention provides a process for
forming a resist pattern comprising the steps of applying the
resist composition onto a substrate to form a coating; heat
treating the coating and then exposing it to high-energy radiation
or electron beams through a photomask; and optionally heat treating
the exposed coating and developing it with a developer.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Ester
[0020] The ester compounds of the invention have the general
formula (1). ##STR8##
[0021] In formula (1), A.sup.1 is a polymerizable functional group
having a carbon-to-carbon double bond. Examples include vinyl,
allyl, 1-propenyl, isopropenyl, norbornenyl, and
tetracyclo[4.4.0.1.sup.2,5.1.sup.7,10] dodecenyl.
[0022] A.sup.2 is a divalent group selected from among furandiyl,
tetrahydrofurandiyl and oxanorbornanediyl. Examples include
furan-2,4-diyl, furan-2,5-diyl, tetrahydrofuran-2,4-diyl,
tetrahydrofuran-2,5-diyl, 7-oxanorbornane-1,2-diyl, and
7-oxanorbornane-1,3-diyl.
[0023] R.sup.1 and R.sup.2 are each independently a straight,
branched or cyclic monovalent hydrocarbon group having 1 to 10
carbon atoms, typically alkyl. Examples include methyl, ethyl,
n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, tert-amyl,
n-pentyl, n-hexyl, cyclopentyl, cyclohexyl, bicyclo[2.2.1]heptyl,
bicyclo[2.2.2]octyl, bicyclo[3.3.1]nonyl, bicyclo[4.4.0]decanyl,
and adamantyl. Alternatively, R.sup.1 and R.sup.2, taken together,
may form an aliphatic hydrocarbon ring of 3 to 20 carbon atoms,
especially 4 to 15 carbon atoms, with the carbon atom to which they
are bonded. Examples of the ring formed include cyclopropane,
cyclobutane, cyclopentane, cyclohexane, bicyclo[2.2.1]heptane,
bicyclo[2.2.2]octane, bicyclo[3.3.1]nonane, bicyclo[4.4.0]decane,
and adamantane.
[0024] R.sup.3 is hydrogen or a straight, branched or cyclic
monovalent hydrocarbon group having 1 to 10 carbon atoms which may
contain a hetero atom, typically oxygen atom. Suitable hydrocarbon
groups are alkyl, hydroxyalkyl, alkoxyalkyl, alkoxyalkoxyalkyl,
alkylcarbonyl, alkoxycarbonyl, carbonyloxy, alkylcarbonyloxy,
alkoxy, carbonyloxyalkyl, and alkylcarbonyloxyalkyl groups.
Specific examples include hydroxymethyl, hydroxyethyl,
methoxymethyl, methoxyethyl, methoxyethoxymethyl, methoxycarbonyl,
formyloxy, acetoxy, pivaloyloxy, cyclohexyloxy, formyloxymethyl,
acetoxymethyl, pivaloyloxymethyl, and cyclohexyloxymethyl.
[0025] Of the ester compounds of formula (1), those having the
general formula (2) are preferred. ##STR9## Herein R.sup.1 and
R.sup.2 are as defined above, and R.sup.4 is hydrogen or
methyl.
[0026] Of the ester compounds of formula (1), those having the
general formula (3) are most preferred. ##STR10## Herein R.sup.1,
R.sup.2 and R.sup.4 are as defined above, and k.sup.1 is 0 or
1.
[0027] Illustrative, non-limiting examples of the ester compounds
of formulae (1) to (3) are given below. Note that Me is methyl and
Ac is acetyl. ##STR11## ##STR12## ##STR13## ##STR14## ##STR15##
##STR16## ##STR17## ##STR18## ##STR19## ##STR20## ##STR21##
[0028] The ester compounds of formula (1) may be obtained, for
example, as seen from the reaction scheme shown below, through the
first step of forming an alcohol intermediate of formula (11) by
any procedure i) to iv), and the second step of esterifying the
hydroxyl group on the alcohol intermediate of formula (11) by a
procedure v), although the process is not limited thereto.
##STR22## Herein, A.sup.1, A.sup.2, and R.sup.1 to R.sup.3 are as
defined above. R.sup.5 is a halogen atom or --OR.sup.8. R.sup.6 is
a divalent hydrocarbon group formed by R.sup.1 and R.sup.2 (i.e.,
--R.sup.1--R.sup.2--) in the event where R.sup.1 and R.sup.2 bond
together to form an aliphatic hydrocarbon ring with the carbon atom
to which they are bonded. R.sup.7 is a hydroxyl group or halogen
atom. R.sup.8 is methyl or ethyl. M is Li, Na, K, MgP or ZnP
wherein P is a halogen atom.
[0029] Referring to the first step, the synthesis of an alcohol
intermediate (11) by procedures i) to iv) is described in
detail.
[0030] Procedure i) is synthesis of the alcohol intermediate (11)
through nucleophilic addition reaction of an organometallic reagent
(4) to a ketone compound (5).
[0031] An appropriate amount of the organometallic reagent (4) used
is 0.5 to 2.0 moles, especially 0.9 to 1.2 moles per mole of the
ketone compound (5). Preferred examples of solvents include ethers
such as tetrahydrofuran, diethyl ether, di-n-butyl ether, and
1,4-dioxane, and hydrocarbons such as n-hexane, n-heptane, benzene,
toluene, xylene and cumene. These solvents may be used alone or in
admixture of any. The reaction temperature and time vary over a
range depending on other reaction conditions. In one example where
a Grignard reagent (corresponding to formula (4) wherein M is MgP)
is used as the organometallic reagent, the reaction temperature is
in a range of -20.degree. C. to 80.degree. C., preferably 0.degree.
C. to 50.degree. C. It is desired for higher yields that the
reaction time is determined by monitoring the reaction until the
completion by gas chromatography (GC) or silica gel thin-layer
chromatography (TLC). The reaction time is usually about 0.5 hour
to about 10 hours. The alcohol intermediate (11) is recovered from
the reaction mixture by a conventional aqueous work-up step. If
necessary, the intermediate is purified by any conventional
technique such as distillation or chromatography.
[0032] Procedure ii) is synthesis of the alcohol intermediate (11)
through nucleophilic addition reaction of an organometallic reagent
(6) to a ketone compound (7).
[0033] An appropriate amount of the organometallic reagent (6) used
is 1.0 to 3.0 moles, especially 1.1 to 1.5 moles per mole of the
ketone compound (7). Preferred examples of solvents include ethers
such as tetrahydrofuran, diethyl ether, di-n-butyl ether, and
1,4-dioxane, and hydrocarbons such as n-hexane, n-heptane, benzene,
toluene, xylene and cumene. These solvents may be used alone or in
admixture of any. The reaction temperature and time vary over a
range depending on other reaction conditions. In one example where
a Grignard reagent (corresponding to formula (6) wherein M is MgP)
is used as the organometallic reagent, the reaction temperature is
in a range of -20.degree. C. to 80.degree. C., preferably 0.degree.
C. to 50.degree. C. It is desired for higher yields that the
reaction time is determined by monitoring the reaction until the
completion by gas chromatography (GC) or silica gel thin-layer
chromatography (TLC). The reaction time is usually about 0.5 hour
to about 10 hours. The alcohol intermediate (11) is recovered from
the reaction mixture by a conventional aqueous work-up step. If
necessary, the intermediate is purified by any conventional
technique such as distillation or chromatography.
[0034] Procedure iii) is synthesis of the alcohol intermediate (11)
through nucleophilic addition reaction of organometallic reagents
(6) and (8) to a carbonyl compound (9).
[0035] An appropriate amount of the organometallic reagents (6) and
(8) used is 2.0 to 5.0 moles, especially 2.0 to 3.0 moles per mole
of the carbonyl compound (9). Preferred examples of solvents
include ethers such as tetrahydrofuran, diethyl ether, di-n-butyl
ether, and 1,4-dioxane, and hydrocarbons such as n-hexane,
n-heptane, benzene, toluene, xylene and cumene. These solvents may
be used alone or in admixture of any. The reaction temperature and
time vary over a range depending on other reaction conditions. In
one example where Grignard reagents (corresponding to formulae (6)
and (8) wherein M is MgP) are used as the organometallic reagent,
the reaction temperature is in a range of 0.degree. C. to
100.degree. C., preferably 20.degree. C. to 70.degree. C. It is
desired for higher yields that the reaction time is determined by
monitoring the reaction until the completion by gas chromatography
(GC) or silica gel thin-layer chromatography (TLC). The reaction
time is usually about 0.5 hour to about 10 hours. The alcohol
intermediate (11) is recovered from the reaction mixture by a
conventional aqueous work-up step. If necessary, the intermediate
is purified by any conventional technique such as distillation or
chromatography.
[0036] Procedure iv) is taken when the alcohol intermediate of the
general formula (11) is represented by the general formula (13):
##STR23## that is, R.sup.1 and R.sup.2 bond together to form an
aliphatic hydrocarbon ring with the carbon atom to which they are
bonded, and is synthesis of the alcohol intermediate (11) through
nucleophilic addition reaction of an organometallic reagent (10) to
a carbonyl compound (9).
[0037] An appropriate amount of the organometallic reagent (10)
used is 1.0 to 3.0 moles, especially 1.1 to 1.5 moles per mole of
the carbonyl compound (9). Preferred examples of solvents include
ethers such as tetrahydrofuran, diethyl ether, di-n-butyl ether,
and 1,4-dioxane, and hydrocarbons such as n-hexane, n-heptane,
benzene, toluene, xylene and cumene. These solvents may be used
alone or in admixture of any. The reaction temperature and time
vary over a range depending on other reaction conditions. In one
example where a Grignard reagent (corresponding to formula (10)
wherein M is MgP) is used as the organometallic reagent, the
reaction temperature is in a range of 0.degree. C. to 100.degree.
C., preferably 20.degree. C. to 70.degree. C. It is desired for
higher yields that the reaction time is determined by monitoring
the reaction until the completion by gas chromatography (GC) or
silica gel thin-layer chromatography (TLC). The reaction time is
usually about 0.5 hour to about 10 hours. The alcohol intermediate
(11) is recovered from the reaction mixture by a conventional
aqueous work-up step. If necessary, the intermediate is purified by
any conventional technique such as distillation or
chromatography.
[0038] The second step v) is to esterify the alcoholic hydroxyl
group resulting from the first step. Esterification is readily
carried out by well-known methods. In one example where an acid
chloride (corresponding to formula (12) wherein R.sup.7 is a
chlorine atom) is employed as the esterifying agent, the alcohol
intermediate (11), a corresponding acid chloride such as
methacrylic acid chloride or norbornenecarboxylic acid chloride and
a base such as triethylamine, pyridine or 4-dimethylaminopyridine
are sequentially or simultaneously added to a solvent such as
methylene chloride, toluene or hexane or in a solventless system,
while heating or cooling if necessary. In another example where a
carboxylic acid (corresponding to formula (12) wherein R.sup.7 is a
hydroxyl group) is employed, a condensation agent such as
N,N-dicyclohexylcarbodiimide is preferably used.
[0039] In the second aspect, the present invention provides a
polymer or high molecular weight compound obtained using the ester
compound of formula (1) as a monomer. Therefore, the polymer
comprises recurring units derived from the ester compound of
formula (1).
[0040] Specifically the recurring units derived from the ester
compound of formula (1) include those of the formulae (1a) to (1c)
below. ##STR24## Herein, A.sup.2, R.sup.1 to R.sup.4, and k.sup.1
are as defined above.
[0041] In addition to the recurring units of formulae (1a) to (1c),
the inventive polymers may further contain recurring units derived
from any of monomers having a polymerizable double bond.
[0042] The recurring units derived from monomers having a
polymerizable double bond include those of the general formulae
(M1) to (M13). ##STR25## ##STR26## Herein, R.sup.001 is hydrogen,
methyl or CH.sub.2CO.sub.2R.sup.003. R.sup.002 is hydrogen, methyl
or CO.sub.2R.sup.003. R.sup.003 is a straight, branched or cyclic
alkyl group of 1 to 15 carbon atoms. R.sup.004 is hydrogen or a
monovalent hydrocarbon group of 1 to 15 carbon atoms having a
carboxyl or hydroxyl group. At least one of R.sup.005 to R.sup.008
represents a monovalent hydrocarbon group of 1 to 15 carbon atoms
having a carboxyl or hydroxyl group while the remaining R's
independently represent hydrogen or a straight, branched or cyclic
alkyl group of 1 to 15 carbon atoms. Alternatively, R.sup.005 to
R.sup.008, taken together, may form a ring, and in that event, at
least one of R.sup.005 to R.sup.008 is a divalent hydrocarbon group
of 1 to 15 carbon atoms having a carboxyl or hydroxyl group, while
the remaining R's are independently single bonds or straight,
branched or cyclic alkylene groups of 1 to 15 carbon atoms.
R.sup.009 is a monovalent hydrocarbon group of 2 to 15 carbon atoms
containing at least one partial structure selected from among
ether, aldehyde, ketone, ester, carbonate, acid anhydride, amide
and imide. At least one of R.sup.010 to R.sup.013 is a monovalent
hydrocarbon group of 2 to 15 carbon atoms containing at least one
partial structure selected from among ether, aldehyde, ketone,
ester, carbonate, acid anhydride, amide and imide, while the
remaining R's are independently hydrogen or straight, branched or
cyclic alkyl groups of 1 to 15 carbon atoms. R.sup.010 to
R.sup.013, taken together, may form a ring, and in that event, at
least one of R.sup.010 to R.sup.013 is a divalent hydrocarbon group
of 1 to 15 carbon atoms containing at least one partial structure
selected from among ether, aldehyde, ketone, ester, carbonate, acid
anhydride, amide and imide, while the remaining R's are
independently single bonds or straight, branched or cyclic alkylene
groups of 1 to 15 carbon atoms. R.sup.014 is a polycyclic
hydrocarbon group having 7 to 15 carbon atoms or an alkyl group
containing a polycyclic hydrocarbon group. R015 is an acid labile
group. X is CH.sub.2 or an oxygen atom or sulfur atom. Y' is --O--
or --(NR.sup.f)--. R.sup.f is hydrogen atom or a straight, branched
or cyclic alkyl group of 1 to 15 carbon atoms. Letter k is 0 or
1.
[0043] More illustratively, R.sup.001 is hydrogen, methyl or
CH.sub.2CO.sub.2R.sup.003. R.sup.002 is hydrogen, methyl or
CO.sub.2R.sup.003. R.sup.003 is a straight, branched or cyclic
alkyl group of 1 to 15 carbon atoms, for example, methyl, ethyl,
propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, tert-amyl,
n-pentyl, n-hexyl, cyclopentyl, cyclohexyl, ethylcyclopentyl,
butylcyclopentyl, ethylcyclohexyl, butylcyclohexyl, adamantyl,
ethyladamantyl, and butyladamantyl.
[0044] R.sup.004 is hydrogen or a monovalent hydrocarbon group of 1
to 15 carbon atoms having a carboxyl or hydroxyl group, for
example, hydrogen, carboxyethyl, carboxybutyl, carboxycyclopentyl,
carboxycyclohexyl, carboxynorbornyl, carboxyadamantyl,
hydroxyethyl, hydroxybutyl, hydroxycyclopentyl, hydroxycyclohexyl,
hydroxynorbornyl, and hydroxyadamantyl.
[0045] At least one of R.sup.005 to R.sup.008 represents a
monovalent hydrocarbon group of 1 to 15 carbon atoms having a
carboxyl or hydroxyl group while the remaining R's independently
represent hydrogen or a straight, branched or cyclic alkyl group of
1 to 15 carbon atoms. Examples of the carboxyl or hydroxyl-bearing
monovalent hydrocarbon group of 1 to 15 carbon atoms include
carboxy, carboxymethyl, carboxyethyl, carboxybutyl, hydroxymethyl,
hydroxyethyl, hydroxybutyl, 2-carboxyethoxycarbonyl,
4-carboxybutoxycarbonyl, 2-hydroxyethoxycarbonyl,
4-hydroxybutoxycarbonyl, carboxycyclopentyloxycarbonyl,
carboxycyclohexyloxycarbonyl, carboxynorbornyloxycarbonyl,
carboxyadamantyloxycarbonyl, hydroxycyclopentyloxycarbonyl,
hydroxycyclohexyloxycarbonyl, hydroxynorbornyloxycarbonyl, and
hydroxyadamantyloxycarbonyl. Examples of the straight, branched or
cyclic alkyl group of 1 to 15 carbon atoms include methyl, ethyl,
propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, tert-amyl,
n-pentyl, n-hexyl, cyclopentyl, cyclohexyl, ethylcyclopentyl,
butylcyclopentyl, ethylcyclohexyl, butylcyclohexyl, adamantyl,
ethyladamantyl, and butyladamantyl.
[0046] Alternatively, R.sup.005 to R.sup.008, taken together, may
form a ring, and in that event, at least one of R.sup.005 to
R.sup.008 is a divalent hydrocarbon group of 1 to 15 carbon atoms
having a carboxyl or hydroxyl group, while the remaining R's are
independently single bonds or straight, branched or cyclic alkylene
groups of 1 to 15 carbon atoms. Examples of the carboxyl or
hydroxyl-bearing divalent hydrocarbon group of 1 to 15 carbon atoms
include the above-exemplified carboxyl or hydroxyl-bearing
monovalent hydrocarbon groups, with one hydrogen atom eliminated
therefrom. Examples of the straight, branched or cyclic alkylene
groups of 1 to 15 carbon atoms include the above-exemplified
straight, branched or cyclic alkyl groups of 1 to 15 carbon atoms,
with one hydrogen atom eliminated therefrom.
[0047] R.sup.009 is a monovalent hydrocarbon group of 2 to 15
carbon atoms containing at least one partial structure selected
from among ether, aldehyde, ketone, ester, carbonate, acid
anhydride, amide and imide. Examples of such hydrocarbon groups
include methoxymethyl, methoxyethoxymethyl, 2-oxooxolan-3-yl,
2-oxooxolan-4-yl, 4,4-dimethyl-2-oxooxolan-3-yl,
4-methyl-2-oxooxan-4-yl, 2-oxo-1,3-dioxolan-4-ylmethyl, and
5-methyl-2-oxooxolan-5-yl, as well as the groups shown below.
##STR27##
[0048] In these formulae and throughout the specification, the
broken line denotes a free valence bond, Me is methyl, and Et is
ethyl.
[0049] At least one of R.sup.010 to R.sup.013 is a monovalent
hydrocarbon group of 2 to 15 carbon atoms containing at least one
partial structure selected from among ether, aldehyde, ketone,
ester, carbonate, acid anhydride, amide and imide, while the
remaining R's are independently hydrogen or straight, branched or
cyclic alkyl groups of 1 to 15 carbon atoms. Examples of the
monovalent hydrocarbon group of 2 to 15 carbon atoms containing at
least one partial structure selected from among ether, aldehyde,
ketone, ester, carbonate, acid anhydride, amide and imide include
methoxymethyl, methoxymethoxymethyl, formyl, methylcarbonyl,
formyloxy, acetoxy, pivaloyloxy, formyloxymethyl, acetoxymethyl,
pivaloyloxymethyl, methoxycarbonyl, 2-oxooxolan-3-yloxycarbonyl,
4,4-dimethyl-2-oxooxolan-3-yloxycarbonyl,
4-methyl-2-oxooxan-4-yloxycarbonyl,
2-oxo-1,3-dioxolan-4-ylmethyloxycarbonyl, and
5-methyl-2-oxooxolan-5-yloxycarbonyl, as well as the groups shown
below. ##STR28##
[0050] Examples of the straight, branched or cyclic alkyl groups of
1 to 15 carbon atoms are the same as exemplified for R.sup.003.
[0051] R.sup.010 to R.sup.013, taken together, may form a ring, and
in that event, at least one of R.sup.010 to R.sup.013 is a divalent
hydrocarbon group of 1 to 15 carbon atoms containing at least one
partial structure selected from among ether, aldehyde, ketone,
ester, carbonate, acid anhydride, amide and imide, while the
remaining R's are independently single bonds or straight, branched
or cyclic alkylene groups of 1 to 15 carbon atoms. Examples of the
divalent hydrocarbon group of 1 to 15 carbon atoms containing at
least one partial structure selected from among ether, aldehyde,
ketone, ester, carbonate, acid anhydride, amide and imide include
2-oxapropane-1,3-diyl, 1,1-dimethyl-2-oxapropane-1,3-diyl,
1-oxo-2-oxapropane-1,3-diyl, 1,3-dioxo-2-oxapropane-1,3-diyl,
1-oxo-2-oxabutane-1,4-diyl, and 1,3-dioxo-2-oxabutane-1,4-diyl, as
well as the groups exemplified as the monovalent hydrocarbon group
of 1 to 15 carbon atoms containing at least one partial structure
selected from among ether, aldehyde, ketone, ester, carbonate, acid
anhydride, amide and imide, with one hydrogen atom eliminated
therefrom. Examples of the straight, branched or cyclic alkylene
groups of 1 to 15 carbon atoms include the groups exemplified for
R.sup.003, with one hydrogen atom eliminated therefrom.
[0052] R.sup.014 is a polycyclic hydrocarbon group having 7 to 15
carbon atoms or an alkyl group containing a polycyclic hydrocarbon
group, for example, norbornyl, bicyclo[3.3.1]nonyl,
tricyclo[5.2.1.0.sup.2,6]decyl, adamantyl, methyladamantyl,
ethyladamantyl, butyladamantyl, norbornylmethyl, and
adamantylmethyl.
[0053] R.sup.015 is an acid labile group. Suitable acid labile
groups include groups of the following general formulae (L1) to
(L4), tertiary alkyl groups of 4 to 20 carbon atoms, preferably 4
to 15 carbon atoms, trialkylsilyl groups in which each alkyl moiety
has 1 to 6 carbon atoms, and oxoalkyl groups of 4 to 20 carbon
atoms. ##STR29##
[0054] R.sup.L01 and R.sup.L02 are hydrogen or straight, branched
or cyclic alkyl groups of 1 to 18 carbon atoms, preferably 1 to 10
carbon atoms. Exemplary alkyl groups include methyl, ethyl, propyl,
isopropyl, n-butyl, sec-butyl, tert-butyl, cyclopentyl, cyclohexyl,
2-ethylhexyl, and n-octyl. R.sup.L03 is a monovalent hydrocarbon
group of 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms,
which may contain a hetero atom such as oxygen, examples of which
include unsubstituted straight, branched or cyclic alkyl groups and
straight, branched or cyclic alkyl groups in which some hydrogen
atoms are replaced by hydroxyl, alkoxy, oxo, amino, alkylamino or
the like. Illustrative examples are the substituted alkyl groups
shown below. ##STR30##
[0055] A pair of R.sup.L01 and R.sup.L02, R.sup.L01 and R.sup.L03,
or R.sup.L02 and R.sup.L03 may bond together to form a ring. Each
of R.sup.L01, R.sup.L02 and R.sup.L03 is a straight or branched
alkylene group of 1 to 18 carbon atoms, preferably 1 to 10 carbon
atoms when they form a ring.
[0056] R.sup.L04 is a tertiary alkyl group of 4 to 20 carbon atoms,
preferably 4 to 15 carbon atoms, a trialkylsilyl group in which
each alkyl moiety has 1 to 6 carbon atoms, an oxoalkyl group of 4
to 20 carbon atoms, or a group of formula (L1). Exemplary tertiary
alkyl groups are tert-butyl, tert-amyl, 1,1-diethylpropyl,
2-cyclopentylpropan-2-yl, 2-cyclohexylpropan-2-yl,
2-(bicyclo[2.2.1]heptan-2-yl)propan-2-yl,
2-(adamantan-1-yl)propan-2-yl, 1-ethylcyclopentyl,
1-butylcyclopentyl, 1-ethylcyclohexyl, 1-butylcyclohexyl,
1-ethyl-2-cyclopentenyl, 1-ethyl-2-cyclohexenyl,
2-methyl-2-adamantyl, and 2-ethyl-2-adamantyl. Exemplary
trialkylsilyl groups are trimethylsilyl, triethylsilyl, and
dimethyl-tert-butylsilyl. Exemplary oxoalkyl groups are
3-oxocyclohexyl, 4-methyl-2-oxooxan-4-yl, and
5-methyl-2-oxooxolan-5-yl. Letter y is an integer of 0 to 6.
[0057] R.sup.L05 is a monovalent hydrocarbon group of 1 to 8 carbon
atoms which may contain a hetero atom or a substituted or
unsubstituted aryl group of 6 to 20 carbon atoms. Examples of the
monovalent hydrocarbon group which may contain a hetero atom
include straight, branched or cyclic alkyl groups such as methyl,
ethyl, propyl, isopropyl, n-butyl, sec-butyl, tert-butyl,
tert-amyl, n-pentyl, n-hexyl, cyclopentyl, and cyclohexyl, and
substituted groups in which some hydrogen atoms on the foregoing
groups are substituted with hydroxyl, alkoxy, carboxy,
alkoxycarbonyl, oxo, amino, alkylamino, cyano, mercapto, alkylthio,
sulfo or other groups. Exemplary aryl groups are phenyl,
methylphenyl, naphthyl, anthryl, phenanthryl, and pyrenyl. Letter m
is equal to 0 or 1, n is equal to 0, 1, 2 or 3, and 2m+n is equal
to 2 or 3.
[0058] R.sup.L06 is a monovalent hydrocarbon group of 1 to 8 carbon
atoms which may contain a hetero atom or a substituted or
unsubstituted aryl group of 6 to 20 carbon atoms. Examples of these
groups are the same as exemplified for R.sup.L05.
[0059] R.sup.L07 to R.sup.L16 independently represent hydrogen or
monovalent hydrocarbon groups of 1 to 15 carbon atoms which may
contain a hetero atom. Exemplary hydrocarbon groups are straight,
branched or cyclic alkyl groups such as methyl, ethyl, propyl,
isopropyl, n-butyl, sec-butyl, tert-butyl, tert-amyl, n-pentyl,
n-hexyl, n-octyl, n-nonyl, n-decyl, cyclopentyl, cyclohexyl,
cyclopentylmethyl, cyclopentylethyl, cyclopentylbutyl,
cyclohexylmethyl, cyclohexylethyl and cyclohexylbutyl, and
substituted ones of these groups in which some hydrogen atoms are
replaced by hydroxyl, alkoxy, carboxy, alkoxycarbonyl, oxo, amino,
alkylamino, cyano, mercapto, alkylthio, sulfo or other groups.
Alternatively, R.sup.L07 to R.sup.L16, taken together, form a ring
(for example, a pair of R.sup.L07 and R.sup.L08, R.sup.L07 and
R.sup.L09, R.sup.L08 and R.sup.L10, R.sup.L09 and R.sup.L10,
R.sup.L11 and R.sup.L12, R.sup.L13 and R.sup.L14, or a similar pair
form a ring). Each of R.sup.L07 to R.sup.L16 represents a divalent
C.sub.1-C.sub.15 hydrocarbon group which may contain a hetero atom,
when they form a ring, examples of which are the ones exemplified
above for the monovalent hydrocarbon groups, with one hydrogen atom
being eliminated. Two of R.sup.L07 to R.sup.L16 which are attached
to adjoining carbon atoms (for example, a pair of R.sup.L07 and
R.sup.L09, R.sup.L09 and R.sup.L15, R.sup.L13 and R.sup.L15, or a
similar pair) may bond together directly to form a double bond.
[0060] Of the acid labile groups of formula (L1), the straight and
branched ones are exemplified by the following groups.
##STR31##
[0061] Of the acid labile groups of formula (L1), the cyclic ones
are, for example, tetrahydrofuran-2-yl,
2-methyltetrahydrofuran-2-yl, tetrahydropyran-2-yl, and
2-methyltetrahydropyran-2-yl.
[0062] Examples of the acid labile groups of formula (L2) include
tert-butoxycarbonyl, tert-butoxycarbonylmethyl,
tert-amyloxycarbonyl, tert-amyloxycarbonylmethyl,
1,1-diethylpropyloxycarbonyl, 1,1-diethylpropyloxycarbonylmethyl,
1-ethylcyclopentyloxycarbonyl, 1-ethylcyclopentyloxycarbonylmethyl,
1-ethyl-2-cyclopentenyloxycarbonyl,
1-ethyl-2-cyclopentenyloxycarbonylmethyl,
1-ethoxyethoxycarbonylmethyl, 2-tetrahydropyranyloxycarbonylmethyl,
and 2-tetrahydrofuranyloxycarbonylmethyl groups.
[0063] Examples of the acid labile groups of formula (L3) include
1-methylcyclopentyl, 1-ethylcyclopentyl, 1-n-propylcyclopentyl,
1-isopropylcyclopentyl, 1-n-butylcyclopentyl,
1-sec-butylcyclopentyl, 1-cyclohexylcyclopentyl,
1-(4-methoxy-n-butyl)cyclopentyl, 1-methylcyclohexyl,
1-ethylcyclohexyl, 3-methyl-l-cyclopenten-3-yl,
3-ethyl-1-cyclopenten-3-yl, 3-methyl-1-cyclohexen-3-yl, and
3-ethyl-1-cyclohexen-3-yl groups.
[0064] The acid labile groups of formula (L4) are exemplified by
the following groups. ##STR32##
[0065] Examples of the tertiary alkyl groups of 4 to 20 carbon
atoms, trialkylsilyl groups in which each alkyl moiety has 1 to 6
carbon atoms, and oxoalkyl groups of 4 to 20 carbon atoms are as
exemplified for R.sup.L04.
[0066] Referring back to formulae (M1) to (M13), X is CH.sub.2 or
an oxygen atom or sulfur atom. Y' is --O-- or --(NR.sup.f)--.
R.sup.f is hydrogen atom or straight, branched or cyclic alkyl
groups of 1 to 15 carbon atoms. Letter k is 0 or 1.
[0067] In addition to the recurring units described above,
recurring units originating from any of other monomers having a
carbon-to-carbon double bond may be introduced into the inventive
polymer. Illustrative examples of such additional compounds are
substituted acrylates such as methyl methacrylate, methyl
crotonate, dimethyl maleate, and dimethyl itaconate; unsaturated
carboxylic acids such as maleic acid, fumaric acid, and itaconic
acid; substituted norbornenes such as norbornene and methyl
norbornene-5-carboxylate; and unsaturated acid anhydrides such as
itaconic anhydride.
[0068] The polymer of the invention should preferably have a weight
average molecular weight (Mw) of about 1,000 to about 500,000, more
preferably about 3,000 to about 100,000, as measured by gel
permeation chromatography (GPC) using polystyrene standards.
Outside the range, there may arise problems such as an extreme
lowering of etching resistance and a lowering of resolution due to
a failure to have a difference in dissolution rate before and after
exposure.
[0069] In the polymers of the invention, the preferred proportion
of recurring units based on the respective monomers is in the
following range (in mol %), though not limited thereto. The
polymers contain: (i) more than 0 mol % to 100 mol %, preferably 10
to 80 mol %, and more preferably 20 to 60 mol % of constituent
units of formulae (1a) to (1c) derived from the monomer of formula
(1), (ii) 0 mol % to less than 100 mol %, preferably 1 to 95 mol %,
and more preferably 40 to 80 mol % of constituent units of one or
more types of formulae (M1) to (M13), and optionally, (iii) 0 to 80
mol %, preferably 0 to 70 mol %, and more preferably 0 to 50 mol %
of constituent units of one or more types derived from another
monomer or monomers.
[0070] The polymers of the invention can be prepared by a variety
of copolymerization reaction methods using the compound of formula
(1) as a first monomer and compounds having a polymerizable double
bond as second and subsequent monomers. The preferred
polymerization reaction is radical polymerization, anionic
polymerization or coordination polymerization.
[0071] For radical polymerization, preferred reaction conditions
include (a) a solvent selected from among hydrocarbons such as
benzene, ethers such as tetrahydrofuran, alcohols such as ethanol,
and ketones such as methyl isobutyl ketone, (b) a polymerization
initiator selected from azo compounds such as
2,2'-azobisisobutyronitrile and peroxides such as benzoyl peroxide
and lauroyl peroxide, (c) a temperature of about 0.degree. C. to
about 100.degree. C., and (d) a time of about 1/2 hour to about 48
hours. Reaction conditions lo outside the described range may be
employed if desired.
[0072] For anionic polymerization, preferred reaction conditions
include (a) a solvent selected from among hydrocarbons such as
benzene, ethers such as tetrahydrofuran, and liquid ammonia, (b) a
polymerization initiator selected from metals such as sodium and
potassium, alkyl metals such as n-butyllithium and
sec-butyllithium, ketyl, and Grignard reagents, (c) a temperature
of about -78.degree. C. to about 0.degree. C., (d) a time of about
1/2 hour to about 48 hours, and (e) a stopper selected from among
proton-donative compounds such as methanol, halides such as methyl
iodide, and electrophilic compounds. Reaction conditions outside
the described range may be employed if desired.
[0073] For coordination polymerization, preferred reaction
conditions include (a) a solvent selected from among hydrocarbons
such as n-heptane and toluene, (b) a catalyst selected from
Ziegler-Natta catalysts comprising a transition metal (e.g.,
titanium) and alkylaluminum, Phillips catalysts of metal oxides
having chromium or nickel compounds carried thereon, and
olefin-metathesis mixed catalysts as typified by tungsten and
rhenium mixed catalysts, (c) a temperature of about 0.degree. C. to
about 100.degree. C., and (d) a time of about 1/2 hour to about 48
hours. Reaction conditions outside the described range may be
employed if desired.
Resist Composition
[0074] Since the polymer of the invention is useful as the base
resin of a resist composition, the other aspect of the invention
provides a resist composition, especially a chemically amplified
positive resist composition, comprising the polymer. Typically, the
resist composition contains the polymer, a photoacid generator, and
an organic solvent, and other optional components.
[0075] Photoacid Generator
[0076] The photoacid generator is a compound capable of generating
an acid upon exposure to high energy radiation or electron beams
and includes the following:
(i) onium salts of the formula (P1a-1), (P1a-2) or (P1b),
(ii) diazomethane derivatives of the formula (P2),
(iii) glyoxime derivatives of the formula (P3),
(iv) bissulfone derivatives of the formula (P4),
(v) sulfonic acid esters of N-hydroxyimide compounds of the formula
(P5),
(vi) .beta.-ketosulfonic acid derivatives,
(vii) disulfone derivatives,
(viii) nitrobenzylsulfonate derivatives,
(ix) sulfonate derivatives, and
(x) oxime sulfonates.
[0077] These photoacid generators are described in detail. (i)
Onium Salts of Formula (P1a-1), (P1a-2) or (P1b): ##STR33##
[0078] Herein, R.sup.101a, R.sup.101b, and R.sup.101c independently
represent straight, branched or cyclic alkyl, alkenyl, oxoalkyl or
oxoalkenyl groups of 1 to 12 carbon atoms, aryl groups of 6 to 20
carbon atoms, or aralkyl or aryloxoalkyl groups of 7 to 12 carbon
atoms, wherein some or all of the hydrogen atoms may be replaced by
alkoxy or other groups. Also, R.sup.101b and R.sup.101c, taken
together, may form a ring. R.sup.101b and R.sup.101c each are
alkylene groups of 1 to 6 carbon atoms when they form a ring.
K.sup.- is a non-nucleophilic counter ion.
[0079] R.sup.101a, R.sup.101b, and R.sup.101c may be the same or
different and are illustrated below. Exemplary alkyl groups include
methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, tert-butyl,
pentyl, hexyl, heptyl, octyl, cyclopentyl, cyclohexyl, cycloheptyl,
cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norbornyl,
and adamantyl. Exemplary alkenyl groups include vinyl, allyl,
propenyl, butenyl, hexenyl, and cyclohexenyl. Exemplary oxoalkyl
groups include 2-oxocyclopentyl and 2-oxocyclohexyl as well as
2-oxopropyl, 2-cyclopentyl-2-oxoethyl, 2-cyclohexyl-2-oxoethyl, and
2-(4-methylcyclohexyl)-2-oxoethyl. Exemplary aryl groups include
phenyl and naphthyl; alkoxyphenyl groups such as p-methoxyphenyl,
m-methoxyphenyl, o-methoxyphenyl, ethoxyphenyl,
p-tert-butoxyphenyl, and m-tert-butoxyphenyl; alkylphenyl groups
such as 2-methylphenyl, 3-methylphenyl, 4-methylphenyl,
ethylphenyl, 4-tert-butylphenyl, 4-butylphenyl, and dimethylphenyl;
alkylnaphthyl groups such as methylnaphthyl and ethylnaphthyl;
alkoxynaphthyl groups such as methoxynaphthyl and ethoxynaphthyl;
dialkylnaphthyl groups such as dimethylnaphthyl and
diethylnaphthyl; and dialkoxynaphthyl groups such as
dimethoxynaphthyl and diethoxynaphthyl. Exemplary aralkyl groups
include benzyl, phenylethyl, and phenethyl. Exemplary aryloxoalkyl
groups are 2-aryl-2-oxoethyl groups such as 2-phenyl-2-oxoethyl,
2-(1-naphthyl)-2-oxoethyl, and 2-(2-naphthyl)-2-oxoethyl. Examples
of the non-nucleophilic counter ion represented by K.sup.- include
halide ions such as chloride and bromide ions, fluoroalkylsulfonate
ions such as triflate, 1,1,1-trifluoroethanesulfonate, and
nonafluorobutanesulfonate, arylsulfonate ions such as tosylate,
benzenesulfonate, 4-fluorobenzenesulfonate, and
1,2,3,4,5-pentafluorobenzenesulfonate, and alkylsulfonate ions such
as mesylate and butanesulfonate. ##STR34##
[0080] Herein, R.sup.102a and R.sup.102b independently represent
straight, branched or cyclic alkyl groups of 1 to 8 carbon atoms.
R.sup.103 represents a straight, branched or cyclic alkylene groups
of 1 to 10 carbon atoms. R.sup.104a and R.sup.104b independently
represent 2-oxoalkyl groups of 3 to 7 carbon atoms. K.sup.- is a
non-nucleophilic counter ion.
[0081] Illustrative of the groups represented by R.sup.102a and
R.sup.102b are methyl, ethyl, propyl, isopropyl, n-butyl,
sec-butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, cyclopentyl,
cyclohexyl, cyclopropylmethyl, 4-methylcyclohexyl, and
cyclohexylmethyl. Illustrative of the groups represented by
R.sup.103 are methylene, ethylene, propylene, butylene, pentylene,
hexylene, heptylene, octylene, nonylene, 1,4-cyclohexylene,
1,2-cyclohexylene, 1,3-cyclopentylene, 1,4-cyclooctylene, and
1,4-cyclohexanedimethylene. Illustrative of the groups represented
by R.sup.104a and R.sup.104b are 2-oxopropyl, 2-oxocyclopentyl,
2-oxocyclohexyl, and 2-oxocycloheptyl. Illustrative examples of the
counter ion represented by K.sup.- are the same as exemplified for
formulae (P1a-1) and (P1a-2). (ii) Diazomethane Derivatives of
Formula (P2) ##STR35##
[0082] Herein, R.sup.105 and R.sup.106 independently represent
straight, branched or cyclic alkyl or halogenated alkyl groups of 1
to 12 carbon atoms, aryl or halogenated aryl groups of 6 to 20
carbon atoms, or aralkyl groups of 7 to 12 carbon atoms.
[0083] Of the groups represented by R.sup.105 and R.sup.106,
exemplary alkyl groups include methyl, ethyl, propyl, isopropyl,
n-butyl, sec-butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, amyl,
cyclopentyl, cyclohexyl, cycloheptyl, norbornyl, and adamantyl.
Exemplary halogenated alkyl groups include trifluoromethyl,
1,1,1-trifluoroethyl, 1,1,1-trichloroethyl, and nonafluorobutyl.
Exemplary aryl groups include phenyl; alkoxyphenyl groups such as
p-methoxyphenyl, m-methoxyphenyl, o-methoxyphenyl, ethoxyphenyl,
p-tert-butoxyphenyl, and m-tert-butoxyphenyl; and alkylphenyl
groups such as 2-methylphenyl, 3-methylphenyl, 4-methylphenyl,
ethylphenyl, 4-tert-butylphenyl, 4-butylphenyl, and dimethylphenyl.
Exemplary halogenated aryl groups include fluorophenyl,
chlorophenyl, and 1,2,3,4,5-pentafluorophenyl. Exemplary aralkyl
groups include benzyl and phenethyl. (iii) Glyoxime Derivatives of
Formula (P3) ##STR36##
[0084] Herein, R.sup.105 is as defined above. R.sup.107, R.sup.108,
and R.sup.109 independently represent straight, branched or cyclic
alkyl or halogenated alkyl groups of 1 to 12 carbon atoms, aryl or
halogenated aryl groups of 6 to 20 carbon atoms, or aralkyl groups
of 7 to 12 carbon atoms. Also, R.sup.108 and R.sup.109, taken
together, may form a ring. R.sup.108 and R.sup.109 each are
straight or branched alkylene groups of 1 to 6 carbon atoms when
they form a ring.
[0085] Illustrative examples of the alkyl, halogenated alkyl, aryl,
halogenated aryl, and aralkyl groups represented by R.sup.107,
R.sup.108, and R.sup.109 are the same as exemplified for R.sup.105
and R.sup.106. Examples of the alkylene groups represented by
R.sup.108 and R.sup.109 include methylene, ethylene, propylene,
butylene, and hexylene. (iv) Bissulfone Derivatives of Formula (P4)
##STR37##
[0086] Herein, R.sup.101a and R.sup.101b are as defined above. (v)
Sulfonic Acid Esters of N-hydroxyimide Compounds of Formula (P5)
##STR38##
[0087] Herein, R.sup.110 is an arylene group of 6 to 10 carbon
atoms, alkylene group of 1 to 6 carbon atoms, or alkenylene group
of 2 to 6 carbon atoms wherein some or all of the hydrogen atoms
may be replaced by straight or branched alkyl or alkoxy groups of 1
to 4 carbon atoms, nitro, acetyl, or phenyl groups. R.sup.111 is a
straight, branched or cyclic alkyl group of 1 to 8 carbon atoms,
alkenyl, alkoxyalkyl, phenyl or naphthyl group wherein some or all
of the hydrogen atoms may be replaced by alkyl or alkoxy groups of
1 to 4 carbon atoms, phenyl groups (which may have substituted
thereon an alkyl or alkoxy of 1 to 4 carbon atoms, nitro, or acetyl
group), hetero-aromatic groups of 3 to 5 carbon atoms, or chlorine
or fluorine atoms.
[0088] Of the groups represented by R.sup.110, exemplary arylene
groups include 1,2-phenylene and 1,8-naphthylene; exemplary
alkylene groups include methylene, ethylene, trimethylene,
tetramethylene, phenylethylene, and norbornane-2,3-diyl; and
exemplary alkenylene groups include 1,2-vinylene,
1-phenyl-1,2-vinylene, and 5-norbornene-2,3-diyl. Of the groups
represented by R.sup.111, exemplary alkyl groups are as exemplified
for R.sup.101a to R.sup.101c; exemplary alkenyl groups include
vinyl, 1-propenyl, allyl, 1-butenyl, 3-butenyl, isoprenyl,
1-pentenyl, 3-pentenyl, 4-pentenyl, dimethylallyl, 1-hexenyl,
3-hexenyl, 5-hexenyl, 1-heptenyl, 3-heptenyl, 6-heptenyl, and
7-octenyl; and exemplary alkoxyalkyl groups include methoxymethyl,
ethoxymethyl, propoxymethyl, butoxymethyl, pentyloxymethyl,
hexyloxymethyl, heptyloxymethyl, methoxyethyl, ethoxyethyl,
propoxyethyl, butoxyethyl, pentyloxyethyl, hexyloxyethyl,
methoxypropyl, ethoxypropyl, propoxypropyl, butoxypropyl,
methoxybutyl, ethoxybutyl, propoxybutyl, methoxypentyl,
ethoxypentyl, methoxyhexyl, and methoxyheptyl.
[0089] Of the substituents on these groups, the alkyl groups of 1
to 4 carbon atoms include methyl, ethyl, propyl, isopropyl,
n-butyl, isobutyl and tert-butyl; and the alkoxy groups of 1 to 4
carbon atoms include methoxy, ethoxy, propoxy, isopropoxy,
n-butoxy, isobutoxy, and tert-butoxy. The phenyl groups which may
have substituted thereon an alkyl or alkoxy of 1 to 4 carbon atoms,
nitro, or acetyl group include phenyl, tolyl, p-tert-butoxyphenyl,
p-acetylphenyl and p-nitrophenyl. The hetero-aromatic groups of 3
to 5 carbon atoms include pyridyl and furyl.
[0090] Illustrative examples of the photoacid generator
include:
[0091] onium salts such as
diphenyliodonium trifluoromethanesulfonate,
(p-tert-butoxyphenyl)phenyliodonium trifluoromethanesulfonate,
diphenyliodonium p-toluenesulfonate,
(p-tert-butoxyphenyl)phenyliodonium p-toluenesulfonate,
triphenylsulfonium trifluoromethanesulfonate,
(p-tert-butoxyphenyl)diphenylsulfonium
trifluoromethanesulfonate,
bis(p-tert-butoxyphenyl)phenylsulfonium
trifluoromethanesulfonate,
tris(p-tert-butoxyphenyl)sulfonium trifluoromethanesulfonate,
triphenylsulfonium p-toluenesulfonate,
(p-tert-butoxyphenyl)diphenylsulfonium p-toluenesulfonate,
bis(p-tert-butoxyphenyl)phenylsulfonium p-toluenesulfonate,
tris(p-tert-butoxyphenyl)sulfonium p-toluenesulfonate,
triphenylsulfonium nonafluorobutanesulfonate,
triphenylsulfonium butanesulfonate,
trimethylsulfonium trifluoromethanesulfonate,
trimethylsulfonium p-toluenesulfonate,
cyclohexylmethyl(2-oxocyclohexyl)sulfonium
trifluoromethanesulfonate,
cyclohexylmethyl(2-oxocyclohexyl)sulfonium p-toluenesulfonate,
dimethylphenylsulfonium trifluoromethanesulfonate,
dimethylphenylsulfonium p-toluenesulfonate,
dicyclohexylphenylsulfonium trifluoromethanesulfonate,
dicyclohexylphenylsulfonium p-toluenesulfonate,
trinaphthylsulfonium trifluoromethanesulfonate,
cyclohexylmethyl(2-oxocyclohexyl)sulfonium
trifluoromethanesulfonate,
(2-norbornyl)methyl(2-oxocyclohexyl)sulfonium
trifluoromethanesulfonate,
ethylenebis[methyl(2-oxocyclopentyl)sulfonium
trifluoromethanesulfonate], and
1,2'-naphthylcarbonylmethyltetrahydrothiophenium triflate;
[0092] diazomethane derivatives such as
bis(benzenesulfonyl)diazomethane,
bis(p-toluenesulfonyl)diazomethane,
bis(xylenesulfonyl)diazomethane,
bis(cyclohexylsulfonyl)diazomethane,
bis(cyclopentylsulfonyl)diazomethane,
bis(n-butylsulfonyl)diazomethane,
bis(isobutylsulfonyl)diazomethane,
bis(sec-butylsulfonyl)diazomethane,
bis(n-propylsulfonyl)diazomethane,
bis(isopropylsulfonyl)diazomethane,
bis(tert-butylsulfonyl)diazomethane,
bis(n-amylsulfonyl)diazomethane,
bis(isoamylsulfonyl)diazomethane,
bis(sec-amylsulfonyl)diazomethane,
bis(tert-amylsulfonyl)diazomethane,
1-cyclohexylsulfonyl-1-(tert-butylsulfonyl)diazomethane,
1-cyclohexylsulfonyl-1-(tert-amylsulfonyl)diazomethane, and
1-tert-amylsulfonyl-1-(tert-butylsulfonyl)diazomethane;
[0093] glyoxime derivatives such as
bis-O-(p-toluenesulfonyl)-.alpha.-dimethylglyoxime,
bis-O-(p-toluenesulfonyl)-.alpha.-diphenylglyoxime,
bis-O-(p-toluenesulfonyl)-.alpha.-dicyclohexylglyoxime,
bis-O-(p-toluenesulfonyl)-2,3-pentanedioneglyoxime,
bis-O-(p-toluenesulfonyl)-2-methyl-3,4-pentanedioneglyoxime,
bis-O-(n-butanesulfonyl)-.alpha.-dimethylglyoxime,
bis-O-(n-butanesulfonyl)-.alpha.-diphenylglyoxime,
bis-O-(n-butanesulfonyl)-.alpha.-dicyclohexylglyoxime,
bis-O-(n-butanesulfonyl)-2,3-pentanedioneglyoxime,
bis-O-(n-butanesulfonyl)-2-methyl-3,4-pentanedioneglyoxime,
bis-O-(methanesulfonyl)-.alpha.-dimethylglyoxime,
bis-O-(trifluoromethanesulfonyl)-.alpha.-dimethylglyoxime,
bis-O-(1,1,1-trifluoroethanesulfonyl)-.alpha.-dimethylglyoxime,
bis-O-(tert-butanesulfonyl)-.alpha.-dimethylglyoxime,
bis-O-(perfluorooctanesulfonyl)-.alpha.-dimethylglyoxime,
bis-O-(cyclohexanesulfonyl)-.alpha.-dimethylglyoxime,
bis-O-(benzenesulfonyl)-.alpha.-dimethylglyoxime,
bis-O-(p-fluorobenzenesulfonyl)-.alpha.-dimethylglyoxime,
bis-O-(p-tert-butylbenzenesulfonyl)-.alpha.-dimethylglyoxime,
bis-O-(xylenesulfonyl)-.alpha.-dimethylglyoxime, and
bis-O-(camphorsulfonyl)-.alpha.-dimethylglyoxime;
[0094] bissulfone derivatives such as
bisnaphthylsulfonylmethane, bistrifluoromethylsulfonylmethane,
bismethylsulfonylmethane, bisethylsulfonylmethane,
bispropylsulfonylmethane, bisisopropylsulfonylmethane,
bis-p-toluenesulfonylmethane, and bisbenzenesulfonylmethane;
[0095] .beta.-ketosulfone derivatives such as
2-cyclohexylcarbonyl-2-(p-toluenesulfonyl)propane and
2-isopropylcarbonyl-2-(p-toluenesulfonyl)propane;
[0096] nitrobenzyl sulfonate derivatives such as
2,6-dinitrobenzyl p-toluenesulfonate and
2,4-dinitrobenzyl p-toluenesulfonate;
[0097] sulfonic acid ester derivatives such as
1,2,3-tris(methanesulfonyloxy)benzene,
1,2,3-tris(trifluoromethanesulfonyloxy)benzene, and
1,2,3-tris(p-toluenesulfonyloxy)benzene; and
[0098] sulfonic acid esters of N-hydroxyimides such as
N-hydroxysuccinimide methanesulfonate,
N-hydroxysuccinimide trifluoromethanesulfonate,
N-hydroxysuccinimide ethanesulfonate,
N-hydroxysuccinimide 1-propanesulfonate,
N-hydroxysuccinimide 2-propanesulfonate,
N-hydroxysuccinimide 1-pentanesulfonate,
N-hydroxysuccinimide 1-octanesulfonate,
N-hydroxysuccinimide p-toluenesulfonate,
N-hydroxysuccinimide p-methoxybenzenesulfonate,
N-hydroxysuccinimide 2-chloroethanesulfonate,
N-hydroxysuccinimide benzenesulfonate,
N-hydroxysuccinimide 2,4,6-trimethylbenzenesulfonate,
N-hydroxysuccinimide 1-naphthalenesulfonate,
N-hydroxysuccinimide 2-naphthalenesulfonate,
N-hydroxy-2-phenylsuccinimide methanesulfonate,
N-hydroxymaleimide methanesulfonate,
N-hydroxymaleimide ethanesulfonate,
N-hydroxy-2-phenylmaleimide methanesulfonate,
N-hydroxyglutarimide methanesulfonate,
N-hydroxyglutarimide benzenesulfonate,
N-hydroxyphthalimide methanesulfonate,
N-hydroxyphthalimide benzenesulfonate,
N-hydroxyphthalimide trifluoromethanesulfonate,
N-hydroxyphthalimide p-toluenesulfonate,
N-hydroxynaphthalimide methanesulfonate,
N-hydroxynaphthalimide benzenesulfonate,
N-hydroxy-5-norbornene-2,3-dicarboxyimide methanesulfonate,
N-hydroxy-5-norbornene-2,3-dicarboxyimide
trifluoromethanesulfonate, and
N-hydroxy-5-norbornene-2,3-dicarboxyimide p-toluenesulfonate.
[0099] Preferred among these photoacid generators are onium salts
such as
triphenylsulfonium trifluoromethanesulfonate,
(p-tert-butoxyphenyl)diphenylsulfonium
trifluoromethanesulfonate,
tris(p-tert-butoxyphenyl)sulfonium trifluoromethanesulfonate,
triphenylsulfonium p-toluenesulfonate,
(p-tert-butoxyphenyl)diphenylsulfonium p-toluenesulfonate,
tris(p-tert-butoxyphenyl)sulfonium p-toluenesulfonate,
trinaphthylsulfonium trifluoromethanesulfonate,
cyclohexylmethyl(2-oxocyclohexyl)sulfonium
trifluoromethanesulfonate,
(2-norbornyl)methyl(2-oxocylohexyl)sulfonium
trifluoromethanesulfonate, and
1,2'-naphthylcarbonylmethyltetrahydrothiophenium triflate;
diazomethane derivatives such as
bis(benzenesulfonyl)diazomethane,
bis(p-toluenesulfonyl)diazomethane,
bis(cyclohexylsulfonyl)diazomethane,
bis(n-butylsulfonyl)diazomethane,
bis(isobutylsulfonyl)diazomethane,
bis(sec-butylsulfonyl)diazomethane,
bis(n-propylsulfonyl)diazomethane,
bis(isopropylsulfonyl)diazomethane, and
bis(tert-butylsulfonyl)diazomethane;
glyoxime derivatives such as
bis-O-(p-toluenesulfonyl)-.alpha.-dimethylglyoxime and
bis-O-(n-butanesulfonyl)-.alpha.-dimethylglyoxime;
bissulfone derivatives such as bisnaphthylsulfonylmethane;
and sulfonic acid esters of N-hydroxyimide compounds such as
N-hydroxysuccinimide methanesulfonate,
N-hydroxysuccinimide trifluoromethanesulfonate,
N-hydroxysuccinimide 1-propanesulfonate,
N-hydroxysuccinimide 2-propanesulfonate,
N-hydroxysuccinimide 1-pentanesulfonate,
N-hydroxysuccinimide p-toluenesulfonate,
N-hydroxynaphthalimide methanesulfonate, and
N-hydroxynaphthalimide benzenesulfonate.
[0100] Also included are the oxime sulfonates described in U.S.
Pat. No. 6,004,724, for example,
(5-(4-toluenesulfonyl)oxyimino-5H-thiophen-2-ylidene)phenylacetonitrile,
(5-(10-camphorsulfonyl)oxyimino-5H-thiophen-2-ylidene)phenylacetonitrile-
,
(5-n-octanesulfonyloxyimino-5H-thiophen-2-ylidene)phenylacetonitrile,
(5-(4-toluenesulfonyl)oxyimino-5H-thiophen-2-ylidene)(2-methylphenyl)ace-
tonitrile,
(5-(10-camphorsulfonyl)oxyimino-5H-thiophen-2-ylidene)(2-methylphenyl)ac-
etonitrile,
(5-n-octanesulfonyloxyimino-5H-thiophen-2-ylidene)(2-methylphenyl)aceton-
itrile, etc.
[0101] Also included are the oxime sulfonates described in U.S.
Pat. No. 6,261,738 and JP-A 2000-314956, for example,
2,2,2-trifluoro-1-phenyl-ethanone oxime-O-methylsulfonate;
2,2,2-trifluoro-1-phenyl-ethanone
oxime-O-(10-camphorylsulfonate);
2,2,2-trifluoro-1-phenyl-ethanone
oxime-O-(4-methoxyphenylsulfonate);
2,2,2-trifluoro-1-phenyl-ethanone
oxime-O-(1-naphthylsulfonate);
2,2,2-trifluoro-1-phenyl-ethanone
oxime-O-(2-naphthylsulfonate);
2,2,2-trifluoro-1-phenyl-ethanone
oxime-O-(2,4,6-trimethylphenylsulfonate);
2,2,2-trifluoro-1-(4-methylphenyl)-ethanone
oxime-O-(10-camphorylsulfonate);
2,2,2-trifluoro-1-(4-methylphenyl)-ethanone
oxime-O-(methylsulfonate);
2,2,2-trifluoro-1-(2-methylphenyl)-ethanone
oxime-O-(10-camphorylsulfonate);
2,2,2-trifluoro-1-(2,4-dimethylphenyl)-ethanone
oxime-O-(10-camphorylsulfonate);
2,2,2-trifluoro-1-(2,4-dimethylphenyl)-ethanone
oxime-O-(1-naphthylsulfonate);
2,2,2-trifluoro-1-(2,4-dimethylphenyl)-ethanone
oxime-O-(2-naphthylsulfonate);
2,2,2-trifluoro-1-(2,4,6-trimethylphenyl)-ethanone
oxime-O-(10-camphorylsulfonate);
2,2,2-trifluoro-1-(2,4,6-trimethylphenyl)-ethanone
oxime-O-(1-naphthylsulfonate);
2,2,2-trifluoro-1-(2,4,6-trimethylphenyl)-ethanone
oxime-O-(2-naphthylsulfonate);
2,2,2-trifluoro-1-(4-methoxyphenyl)-ethanone
oxime-O-methylsulfonate;
2,2,2-trifluoro-1-(4-methylthiophenyl)-ethanone
oxime-O-methylsulfonate;
2,2,2-trifluoro-1-(3,4-dimethoxyphenyl)-ethanone
oxime-O-methylsulfonate;
2,2,3,3,4,4,4-heptafluoro-1-phenyl-butanone
oxime-O-(10-camphorylsulfonate);
2,2,2-trifluoro-1-(phenyl)-ethanone oxime-O-methylsulfonate;
2,2,2-trifluoro-1-(phenyl)-ethanone
oxime-O-10-camphoryl-sulfonate;
2,2,2-trifluoro-1-(phenyl)-ethanone
oxime-O-(4-methoxyphenyl)sulfonate;
2,2,2-trifluoro-1-(phenyl)-ethanone
oxime-O-(1-naphthyl)-sulfonate;
2,2,2-trifluoro-1-(phenyl)-ethanone
oxime-O-(2-naphthyl)-sulfonate;
2,2,2-trifluoro-1-(phenyl)-ethanone
oxime-O-(2,4,6-trimethylphenyl)sulfonate;
2,2,2-trifluoro-1-(4-methylphenyl)-ethanone
oxime-O-(10-camphoryl)sulfonate;
2,2,2-trifluoro-1-(4-methylphenyl)-ethanone
oxime-O-methylsulfonate;
2,2,2-trifluoro-1-(2-methylphenyl)-ethanone
oxime-O-(10-camphoryl)sulfonate;
2,2,2-trifluoro-1-(2,4-dimethylphenyl)-ethanone
oxime-O-(1-naphthyl)sulfonate;
2,2,2-trifluoro-1-(2,4-dimethylphenyl)-ethanone
oxime-O-(2-naphthyl)sulfonate;
2,2,2-trifluoro-1-(2,4,6-trimethylphenyl)-ethanone
oxime-O-(10-camphoryl)sulfonate;
2,2,2-trifluoro-1-(2,4,6-trimethylphenyl)-ethanone
oxime-O-(1-naphthyl)sulfonate;
2,2,2-trifluoro-1-(2,4,6-trimethylphenyl)-ethanone
oxime-O-(2-naphthyl)sulfonate;
2,2,2-trifluoro-1-(4-methoxyphenyl)-ethanone
oxime-O-methylsulfonate;
2,2,2-trifluoro-1-(4-thiomethylphenyl)-ethanone
oxime-O-methylsulfonate;
2,2,2-trifluoro-1-(3,4-dimethoxyphenyl)-ethanone
oxime-O-methylsulfonate;
2,2,2-trifluoro-1-(4-methoxyphenyl)-ethanone
oxime-O-(4-methylphenyl)sulfonate;
2,2,2-trifluoro-1-(4-methoxyphenyl)-ethanone
oxime-O-(4-methoxyphenyl)sulfonate;
2,2,2-trifluoro-1-(4-methoxyphenyl)-ethanone
oxime-O-(4-dodecylphenyl)sulfonate;
2,2,2-trifluoro-1-(4-methoxyphenyl)-ethanone
oxime-O-octylsulfonate;
2,2,2-trifluoro-1-(4-thiomethylphenyl)-ethanone
oxime-O-(4-methoxyphenyl)sulfonate;
2,2,2-trifluoro-1-(4-thiomethylphenyl)-ethanone
oxime-O-(4-dodecylphenyl)sulfonate;
2,2,2-trifluoro-1-(4-thiomethylphenyl)-ethanone
oxime-O-octylsulfonate;
2,2,2-trifluoro-1-(4-thiomethylphenyl)-ethanone
oxime-O-(2-naphthyl)sulfonate;
2,2,2-trifluoro-1-(2-methylphenyl)-ethanone
oxime-O-methylsulfonate;
2,2,2-trifluoro-1-(4-methylphenyl)-ethanone
oxime-O-phenylsulfonate;
2,2,2-trifluoro-1-(4-chlorophenyl)-ethanone
oxime-O-phenylsulfonate;
2,2,3,3,4,4,4-heptafluoro-1-(phenyl)-butanone
oxime-O-(10-camphoryl)sulfonate;
2,2,2-trifluoro-1-naphthyl-ethanone oxime-O-methylsulfonate;
2,2,2-trifluoro-2-naphthyl-ethanone oxime-O-methylsulfonate;
2,2,2-trifluoro-1-[4-benzylphenyl]-ethanone
oxime-O-methylsulfonate;
2,2,2-trifluoro-1-[4-(phenyl-1,4-dioxa-but-1-yl)phenyl]-ethanone
oxime-O-methylsulfonate;
2,2,2-trifluoro-1-naphthyl-ethanone oxime-O-propylsulfonate;
2,2,2-trifluoro-2-naphthyl-ethanone oxime-O-propylsulfonate;
2,2,2-trifluoro-1-[4-benzylphenyl]-ethanone
oxime-O-propylsulfonate;
2,2,2-trifluoro-1-[4-methylsulfonylphenyl]-ethanone
oxime-O-propylsulfonate;
1,3-bis[1-(4-phenoxyphenyl)-2,2,2-trifluoroethanone
oxime-O-sulfonyl]phenyl;
2,2,2-trifluoro-1-[4-methylsulfonyloxyphenyl]-ethanone
oxime-O-propylsulfonate;
2,2,2-trifluoro-1-[4-methylcarbonyloxyphenyl]-ethanone
oxime-O-propylsulfonate;
2,2,2-trifluoro-1-[6H,7H-5,8-dioxonaphth-2-yl]-ethanone
oxime-O-propylsulfonate;
2,2,2-trifluoro-1-[4-methoxycarbonylmethoxyphenyl]-ethanone
oxime-O-propylsulfonate;
2,2,2-trifluoro-1-[4-(methoxycarbonyl)-(4-amino-1-oxa-pent-1-yl)-phenyl]-
-ethanone oxime-O-propylsulfonate;
2,2,2-trifluoro-1-(3,5-dimethyl-4-ethoxyphenyl)-ethanone
oxime-O-propylsulfonate;
2,2,2-trifluoro-1-[4-benzyloxyphenyl]-ethanone
oxime-O-propylsulfonate;
2,2,2-trifluoro-1-[2-thiophenyl]-ethanone oxime-O-propylsulfonate;
and
2,2,2-trifluoro-1-[1-dioxa-thiophen-2-yl)]-ethanone
oxime-O-propylsulfonate.
[0102] Also included are the oxime sulfonates described in JP-A
9-95479 and JP-A 9-230588 and the references cited therein, for
example,
.alpha.-(p-toluenesulfonyloxyimino)-phenylacetonitrile,
.alpha.-(p-chlorobenzenesulfonyloxyimino)-phenylacetonitrile,
.alpha.-(4-nitrobenzenesulfonyloxyimino)-phenylacetonitrile,
.alpha.-(4-nitro-2-trifluoromethylbenzenesulfonyloxyimino)-phenylacetoni-
trile,
.alpha.-(benzenesulfonyloxyimino)-4-chlorophenylacetonitrile,
.alpha.-(benzenesulfonyloxyimino)-2,4-dichlorophenylacetonitrile,
.alpha.-(benzenesulfonyloxyimino)-2,6-dichlorophenylacetonitrile,
.alpha.-(benzenesulfonyloxyimino)-4-methoxyphenylacetonitrile,
.alpha.-(2-chlorobenzenesulfonyloxyimino)-4-methoxyphenylacetonitrile,
.alpha.-(benzenesulfonyloxyimino)-2-thienylacetonitrile,
.alpha.-(4-dodecylbenzenesulfonyloxyimino)-phenylacetonitrile,
.alpha.-[(4-toluenesulfonyloxyimino)-4-methoxyphenyl]acetonitrile,
.alpha.-[(dodecylbenzenesulfonyloxyimino)-4-methoxyphenyl]acetonitrile,
.alpha.-(tosyloxyimino)-3-thienylacetonitrile,
.alpha.-(methylsulfonyloxyimino)-1-cyclopentenylacetonitrile,
.alpha.-(ethylsulfonyloxyimino)-1-cyclopentenylacetonitrile,
.alpha.-(isopropylsulfonyloxyimino)-1-cyclopentenylacetonitrile,
.alpha.-(n-butylsulfonyloxyimino)-1-cyclopentenylacetonitrile,
.alpha.-(ethylsulfonyloxyimino)-1-cyclohexenylacetonitrile,
.alpha.-(isopropylsulfonyloxyimino)-1-cyclohexenylacetonitrile,
and
.alpha.-(n-butylsulfonyloxyimino)-1-cyclohexenylacetonitrile.
[0103] Suitable bisoxime sulfonates include those described in JP-A
9-208554, for example,
bis(.alpha.-(4-toluenesulfonyloxy)imino)-p-phenylenediacetonitrile,
bis(.alpha.-(benzenesulfonyloxy)imino)-p-phenylenediacetonitrile,
bis(.alpha.-(methanesulfonyloxy)imino)-p-phenylenediacetonitrile,
bis(.alpha.-(butanesulfonyloxy)imino)-p-phenylenediacetonitrile,
bis(.alpha.-(10-camphorsulfonyloxy)imino)-p-phenylenediacetonitrile,
bis(.alpha.-(4-toluenesulfonyloxy)imino)-p-phenylenediacetonitrile,
bis(.alpha.-(trifluoromethanesulfonyloxy)imino)-p-phenylenediacetonitril-
e,
bis(.alpha.-(4-methoxybenzenesulfonyloxy)imino)-p-phenylenediacetonitril-
e,
bis(.alpha.-(4-toluenesulfonyloxy)imino)-m-phenylenediacetonitrile,
bis(.alpha.-(benzenesulfonyloxy)imino)-m-phenylenediacetonitrile,
bis(.alpha.-(methanesulfonyloxy)imino)-m-phenylenediacetonitrile,
bis(.alpha.-(butanesulfonyloxy)imino)-m-phenylenediacetonitrile,
bis(.alpha.-(10-camphorsulfonyloxy)imino)-m-phenylenediacetonitrile,
bis(.alpha.-(4-toluenesulfonyloxy)imino)-m-phenylenediacetonitrile,
bis(.alpha.-(trifluoromethanesulfonyloxy)imino)-m-phenylenediacetonitril-
e,
bis(.alpha.-(
4-methoxybenzenesulfonyloxy)imino)-m-phenylenediacetonitrile,
etc.
[0104] These photoacid generators may be used singly or in
combinations of two or more thereof. Onium salts are effective for
improving rectangularity, while diazomethane derivatives and
glyoxime derivatives are effective for reducing standing waves. The
combination of an onium salt with a diazomethane or a glyoxime
derivative allows for fine adjustment of the profile.
[0105] The photoacid generator is added in an amount of 0.1 to 50
parts, and especially 0.5 to 40 parts by weight, per 100 parts by
weight of the base resin (all parts are by weight, hereinafter).
Less than 0.1 part of the photoacid generator may generate a less
amount of acid upon exposure, sometimes leading to a poor
sensitivity and resolution whereas more than 50 parts of the
photoacid generator may adversely affect the transmittance and
resolution of resist.
[0106] Organic Solvent
[0107] The organic solvent used herein may be any organic solvent
in which the base resin, photoacid generator, and other components
are soluble. Illustrative, non-limiting, examples of the organic
solvent include ketones such as cyclohexanone and
methyl-2-n-amylketone; alcohols such as 3-methoxybutanol,
3-methyl-3-methoxybutanol, 1-methoxy-2-propanol, and
1-ethoxy-2-propanol; ethers such as propylene glycol monomethyl
ether, ethylene glycol monomethyl ether, propylene glycol monoethyl
ether, ethylene glycol monoethyl ether, propylene glycol dimethyl
ether, and diethylene glycol dimethyl ether; esters such as
propylene glycol monomethyl ether acetate, propylene glycol
monoethyl ether acetate, ethyl lactate, ethyl pyruvate, butyl
acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate,
tert-butyl acetate, tert-butyl propionate, and propylene glycol
mono-tert-butyl ether acetate; and lactones such as
y-butyrolactone. These solvents may be used alone or in
combinations of two or more thereof. Of the above organic solvents,
it is recommended to use diethylene glycol dimethyl ether and
1-ethoxy-2-propanol in which the photoacid generator is most
soluble, propylene glycol monomethyl ether acetate, or a mixture
thereof.
[0108] An appropriate amount of the organic solvent used is about
200 to 1,000 parts, especially about 400 to 800 parts by weight per
100 parts by weight of the base resin.
[0109] Dissolution Inhibitor
[0110] To the resist composition, a dissolution inhibitor may be
added. The dissolution inhibitor is a compound having on the
molecule at least two phenolic hydroxyl groups, in which an average
of from 0 to 100 mol % of all the hydrogen atoms on the phenolic
hydroxyl groups are replaced with acid labile groups or a compound
having on the molecule at least one carboxyl group, in which an
average of 50 to 100 mol % of all the hydrogen atoms on the
carboxyl groups are replaced with acid labile groups, both the
compounds having an average molecular weight within a range of 100
to 1,000, and preferably 150 to 800.
[0111] The degree of substitution of the hydrogen atoms on the
phenolic hydroxyl groups with acid labile groups is on average at
least 0 mol %, and preferably at least 30 mol %, of all the
phenolic hydroxyl groups. The upper limit is 100 mol %, and
preferably 80 mol %. The degree of substitution of the hydrogen
atoms on the carboxyl groups with acid labile groups is on average
at least 50 mol %, and preferably at least 70 mol %, of all the
carboxyl groups, with the upper limit being 100 mol %.
[0112] Preferable examples of such compounds having two or more
phenolic hydroxyl groups or compounds having at least one carboxyl
group include those of formulas (D1) to (D14) below. ##STR39##
##STR40##
[0113] In these formulas, R.sup.201 and R.sup.202 are each hydrogen
or a straight or branched alkyl or alkenyl of 1 to 8 carbon atoms;
R.sup.203 is hydrogen, a straight or branched alkyl or alkenyl of 1
to 8 carbon atoms, or --(R.sup.207).sub.h--COOH; R.sup.204 is
--(CH.sub.2).sub.i-- (where i=2 to 10), an arylene of 6 to 10
carbon atoms, carbonyl, sulfonyl, an oxygen atom, or a sulfur atom;
R.sup.205 is an alkylene of 1 to 10 carbon atoms, an arylene of 6
to 10 carbon atoms, carbonyl, sulfonyl, an oxygen atom, or a sulfur
atom; R.sup.206 is hydrogen, a straight or branched alkyl or
alkenyl of 1 to 8 carbon atoms, or a hydroxyl-substituted phenyl or
naphthyl; R.sup.207 is a straight or branched alkylene of 1 to 10
carbon atoms; R.sup.208 is hydrogen or hydroxyl; the letter j is an
integer from 0 to 5; u and h are each 0 or 1; s, t, s', t', s'',
and t'' are each numbers which satisfy s+t=8, s'+t'=5, and
s''+t''=4, and are such that each phenyl skeleton has at least one
hydroxyl group; and .alpha. is a number such that the compounds of
formula (D8) or (D9) have a molecular weight of from 100 to
1,000.
[0114] In the above formulas, suitable examples of R.sup.201 and
R.sup.202 include hydrogen, methyl, ethyl, butyl, propyl, ethynyl,
and cyclohexyl; suitable examples of R.sup.203 include the same
groups as for R.sup.201 and R.sup.202, as well as --COOH and
--CH.sub.2COOH; suitable examples of R.sup.204 include ethylene,
phenylene, carbonyl, sulfonyl, oxygen, and sulfur; suitable
examples of R.sup.205 include methylene as well as the same groups
as for R.sup.204; and suitable examples of R.sup.206 include
hydrogen, methyl, ethyl, butyl, propyl, ethynyl, cyclohexyl, and
hydroxyl-substituted phenyl or naphthyl.
[0115] Exemplary acid labile groups on the dissolution inhibitor
include a variety of such groups, and typically groups of the
following general formulae (L1) to (L4), tertiary alkyl groups of 4
to 20 carbon atoms, trialkylsilyl groups in which each of the
alkyls has 1 to 6 carbon atoms, and oxoalkyl groups of 4 to 20
carbon atoms. ##STR41##
[0116] In these formulas, R.sup.L01 and R.sup.L02 are each hydrogen
or a straight, branched or cyclic alkyl having 1 to 18 carbon
atoms; and R.sup.L03 is a monovalent hydrocarbon group of 1 to 18
carbon atoms which may contain a heteroatom (e.g., oxygen). A pair
of R.sup.L01 and R.sup.L02, a pair of R.sup.L01 and R.sup.L03 or a
pair of R.sup.L02 and R.sup.L03 may together form a ring, with the
proviso that R.sup.L01, R.sup.L02, and R.sup.L03 are each a
straight or branched alkylene of 1 to 18 carbon atoms when they
form a ring. R.sup.L04 is a tertiary alkyl group of 4 to 20 carbon
atoms, a trialkysilyl group in which each of the alkyls has 1 to 6
carbon atoms, an oxoalkyl group of 4 to 20 carbon atoms, or a group
of the formula (L1). R.sup.L05 is a monovalent hydrocarbon groups
of 1 to 8 carbon atoms which may contain a hetero atom or a
substituted or unsubstituted aryl group of 6 to 20 carbon atoms.
R.sup.L06 is a monovalent hydrocarbon groups of 1 to 8 carbon atoms
which may contain a hetero atom or a substituted or unsubstituted
aryl group of 6 to 20 carbon atoms. R.sup.L07 to R.sup.L16
independently represent hydrogen or monovalent hydrocarbon groups
of 1 to 15 carbon atoms which may contain a hetero atom.
Alternatively, R.sup.L07 to R.sup.L16, taken together, may form a
ring. Each of R.sup.L07 to R.sup.L16 represents a divalent
C.sub.1-C.sub.15 hydrocarbon group which may contain a hetero atom,
when they form a ring. Two of R.sup.L07 to R.sup.L16 which are
attached to adjoining carbon atoms may bond together directly to
form a double bond. Letter y is an integer of 0 to 6. Letter m is
equal to 0 or 1, n is equal to 0, 1, 2 or 3, and 2m+n is equal to 2
or 3. Illustrative examples of these groups are as previously
exemplified.
[0117] The dissolution inhibitor may be formulated in an amount of
0 to 50 parts, preferably 0 to 40 parts, and more preferably 0 to
30 parts, per 100 parts of the base resin, and may be used singly
or as a mixture of two or more thereof. The use of more than 50
parts would lead to slimming of the patterned film, and thus a
decline in resolution.
[0118] The dissolution inhibitor can be synthesized by introducing
acid labile groups into a compound having phenolic hydroxyl or
carboxyl groups in accordance with an organic chemical
formulation.
[0119] Basic Compound
[0120] In the resist composition of the invention, a basic compound
may be blended. A suitable basic compound used herein is a compound
capable of suppressing the rate of diffusion when the acid
generated by the photoacid generator diffuses within the resist
film. The inclusion of this type of basic compound holds down the
rate of acid diffusion within the resist film, resulting in better
resolution. In addition, it suppresses changes in sensitivity
following exposure, thus reducing substrate and environment
dependence, as well as improving the exposure latitude and the
pattern profile.
[0121] Examples of basic compounds include primary, secondary, and
tertiary aliphatic amines, mixed amines, aromatic amines,
heterocyclic amines, carboxyl group-bearing nitrogenous compounds,
sulfonyl group-bearing nitrogenous compounds, hydroxyl
group-bearing nitrogenous compounds, hydroxyphenyl group-bearing
nitrogenous compounds, alcoholic nitrogenous compounds, amide
derivatives, and imide derivatives.
[0122] Examples of suitable primary aliphatic amines include
ammonia, methylamine, ethylamine, n-propylamine, isopropylamine,
n-butylamine, isobutylamine, sec-butylamine, tert-butylamine,
pentylamine, tert-amylamine, cyclopentylamine, hexylamine,
cyclohexylamine, heptylamine, octylamine, nonylamine, decylamine,
dodecylamine, cetylamine, methylenediamine, ethylenediamine, and
tetraethylenepentamine. Examples of suitable secondary aliphatic
amines include dimethylamine, diethylamine, di-n-propylamine,
diisopropylamine, di-n-butylamine, diisobutylamine,
di-sec-butylamine, dipentylamine, dicyclopentylamine, dihexylamine,
dicyclohexylamine, diheptylamine, dioctylamine, dinonylamine,
didecylamine, didodecylamine, dicetylamine, N,
N-dimethylmethylenediamine, N, N-dimethylethylenediamine, and
N,N-dimethyltetraethylenepentamine. Examples of suitable tertiary
aliphatic amines include trimethylamine, triethylamine,
tri-n-propylamine, triisopropylamine, tri-n-butylamine,
triisobutylamine, tri-sec-butylamine, tripentylamine,
tricyclopentylamine, trihexylamine, tricyclohexylamine,
triheptylamine, trioctylamine, trinonylamine, tridecylamine,
tridodecylamine, tricetylamine,
N,N,N',N'-tetramethylmethylenediamine,
N,N,N',N'-tetramethylethylenediamine, and
N,N,N',N'-tetramethyltetraethylenepentamine.
[0123] Examples of suitable mixed amines include
dimethylethylamine, methylethylpropylamine, benzylamine,
phenethylamine, and benzyldimethylamine. Examples of suitable
aromatic and heterocyclic amines include aniline derivatives (e.g.,
aniline, N-methylaniline, N-ethylaniline, N-propylaniline,
N,N-dimethylaniline, 2-methylaniline, 3-methylaniline,
4-methylaniline, ethylaniline, propylaniline, trimethylaniline,
2-nitroaniline, 3-nitroaniline, 4-nitroaniline, 2,4-dinitroaniline,
2,6-dinitroaniline, 3,5-dinitroaniline, and N,N-dimethyltoluidine),
diphenyl(p-tolyl)amine, methyldiphenylamine, triphenylamine,
phenylenediamine, naphthylamine, diaminonaphthalene, pyrrole
derivatives (e.g., pyrrole, 2H-pyrrole, 1-methylpyrrole,
2,4-dimethylpyrrole, 2,5-dimethylpyrrole, and N-methylpyrrole),
oxazole derivatives (e.g., oxazole and isooxazole), thiazole
derivatives (e.g., thiazole and isothiazole), imidazole derivatives
(e.g., imidazole, 4-methylimidazole, and
4-methyl-2-phenylimidazole), pyrazole derivatives, furazan
derivatives, pyrroline derivatives (e.g., pyrroline and
2-methyl-1-pyrroline), pyrrolidine derivatives (e.g., pyrrolidine,
N-methylpyrrolidine, pyrrolidinone, and N-methylpyrrolidone),
imidazoline derivatives, imidazolidine derivatives, pyridine
derivatives (e.g., pyridine, methylpyridine, ethylpyridine,
propylpyridine, butylpyridine, 4-(1-butylpentyl)pyridine,
dimethylpyridine, trimethylpyridine, triethylpyridine,
phenylpyridine, 3-methyl-2-phenylpyridine, 4-tert-butylpyridine,
diphenylpyridine, benzylpyridine, methoxypyridine, butoxypyridine,
dimethoxypyridine, 1-methyl-2-pyridine, 4-pyrrolidinopyridine,
1-methyl-4-phenylpyridine, 2-(1-ethylpropyl)pyridine,
aminopyridine, and dimethylaminopyridine), pyridazine derivatives,
pyrimidine derivatives, pyrazine derivatives, pyrazoline
derivatives, pyrazolidine derivatives, piperidine derivatives,
piperazine derivatives, morpholine derivatives, indole derivatives,
isoindole derivatives, 1H-indazole derivatives, indoline
derivatives, quinoline derivatives (e.g., quinoline and
3-quinolinecarbonitrile), isoquinoline derivatives, cinnoline
derivatives, quinazoline derivatives, quinoxaline derivatives,
phthalazine derivatives, purine derivatives, pteridine derivatives,
carbazole derivatives, phenanthridine derivatives, acridine
derivatives, phenazine derivatives, 1,10-phenanthroline
derivatives, adenine derivatives, adenosine derivatives, guanine
derivatives, guanosine derivatives, uracil derivatives, and uridine
derivatives.
[0124] Examples of suitable carboxyl group-bearing nitrogenous
compounds include aminobenzoic acid, indolecarboxylic acid, and
amino acid derivatives (e.g. nicotinic acid, alanine, alginine,
aspartic acid, glutamic acid, glycine, histidine, isoleucine,
glycylleucine, leucine, methionine, phenylalanine, threonine,
lysine, 3-aminopyrazine-2-carboxylic acid, and methoxyalanine).
Examples of suitable sulfonyl group-bearing nitrogenous compounds
include 3-pyridinesulfonic acid and pyridinium p-toluenesulfonate.
Examples of suitable hydroxyl group-bearing nitrogenous compounds,
hydroxyphenyl group-bearing nitrogenous compounds, and alcoholic
nitrogenous compounds include 2-hydroxypyridine, aminocresol,
2,4-quinolinediol, 3-indolemethanol hydrate, monoethanolamine,
diethanolamine, triethanolamine, N-ethyldiethanolamine,
N,N-diethylethanolamine, triisopropanolamine, 2,2'-iminodiethanol,
2-aminoethanol, 3-amino-1-propanol, 4-amino-1-butanol,
4-(2-hydroxyethyl)morpholine, 2-(2-hydroxyethyl)pyridine,
1-(2-hydroxyethyl)piperazine,
1-[2-(2-hydroxyethoxy)ethyl]piperazine, piperidine ethanol,
1-(2-hydroxyethyl)pyrrolidine, 1-(2-hydroxyethyl)-2-pyrrolidinone,
3-piperidino-1,2-propanediol, 3-pyrrolidino-1,2-propanediol,
8-hydroxyjulolidine, 3-quinuclidinol, 3-tropanol,
1-methyl-2-pyrrolidine ethanol, 1-aziridine ethanol,
N-(2-hydroxyethyl)phthalimide, and
N-(2-hydroxyethyl)isonicotinamide. Examples of suitable amide
derivatives include formamide, N-methylformamide,
N,N-dimethylformamide, acetamide, N-methylacetamide,
N,N-dimethylacetamide, propionamide, and benzamide. Suitable imide
derivatives include phthalimide, succinimide, and maleimide.
[0125] In addition, basic compounds of the following general
formula (B)-1 may also be included alone or in admixture.
N(X).sub.n(Y).sub.3-n (B)-1
[0126] In the formula, n is equal to 1, 2 or 3; side chain Y is
independently hydrogen or a straight, branched or cyclic alkyl
group of 1 to 20 carbon atoms which may contain an ether or
hydroxyl group; and side chain X is independently selected from
groups of the following general formulas (X)-1to (X)-3, and two or
three X's may bond together to form a ring. ##STR42##
[0127] In the formulas, R.sup.300, R.sup.302 and R.sup.305 are
independently straight or branched alkylene groups of 1 to 4 carbon
atoms; R.sup.301 and R.sup.304 are independently hydrogen,
straight, branched or cyclic alkyl groups of 1 to 20 carbon atoms,
which may contain at least one hydroxyl, ether, ester group or
lactone ring; R.sup.303 is a single bond or a straight or branched
alkylene group of 1 to 4 carbon atoms; and R.sup.306 is a straight,
branched or cyclic alkyl group of 1 to 20 carbon atoms, which may
contain at least one hydroxyl, ether, ester group or lactone
ring.
[0128] Illustrative examples of the basic compounds of formula
(B)-1 include tris(2-methoxymethoxyethyl)amine,
tris{2-(2-methoxyethoxy)ethyl}amine,
tris{2-(2-methoxyethoxymethoxy)ethyl}amine,
tris{2-(1-methoxyethoxy)ethyl}amine,
tris{2-(1-ethoxyethoxy)ethyl}amine,
tris{2-(1-ethoxypropoxy)ethyl}amine,
tris[2-{2-(2-hydroxyethoxy)ethoxy}ethyl]amine,
4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane,
4,7,13,18-tetraoxa-1,10-diazabicyclo[8.5.5]eicosane,
1,4,10,13-tetraoxa-7,16-diazabicyclooctadecane,
1-aza-12-crown-4, 1-aza-15-crown-5, 1-aza-18-crown-6,
tris(2-formyloxyethyl)amine, tris(2-acetoxyethyl)amine,
tris(2-propionyloxyethyl)amine, tris(2-butyryloxyethyl)amine,
tris(2-isobutyryloxyethyl)amine, tris(2-valeryloxyethyl)amine,
tris(2-pivaloyloxyethyl)amine,
N,N-bis(2-acetoxyethyl)-2-(acetoxyacetoxy)ethylamine,
tris(2-methoxycarbonyloxyethyl)amine,
tris(2-tert-butoxycarbonyloxyethyl)amine,
tris[2-(2-oxopropoxy)ethyl]amine,
tris[2-(methoxycarbonylmethyl)oxyethyl]amine,
tris[2-(tert-butoxycarbonylmethyloxy)ethyl]amine,
tris[2-(cyclohexyloxycarbonylmethyloxy)ethyl]amine,
tris(2-methoxycarbonylethyl)amine,
tris(2-ethoxycarbonylethyl)amine,
N,N-bis(2-hydroxyethyl)-2-(methoxycarbonyl)ethylamine,
N,N-bis(2-acetoxyethyl)-2-(methoxycarbonyl)ethylamine,
N,N-bis(2-hydroxyethyl)-2-(ethoxycarbonyl)ethylamine,
N,N-bis(2-acetoxyethyl)-2-(ethoxycarbonyl)ethylamine,
N,N-bis(2-hydroxyethyl)-2-(2-methoxyethoxycarbonyl)ethylamine,
N,N-bis(2-acetoxyethyl)-2-(2-methoxyethoxycarbonyl)ethylamine,
N,N-bis(2-hydroxyethyl)-2-(2-hydroxyethoxycarbonyl)ethylamine,
N,N-bis(2-acetoxyethyl)-2-(2-acetoxyethoxycarbonyl)ethylamine,
N,N-bis(2-hydroxyethyl)-2-[(methoxycarbonyl)methoxycarbonyl]ethylamine,
N,N-bis(2-acetoxyethyl)-2-[(methoxycarbonyl)methoxycarbonyl]ethylamine,
N,N-bis(2-hydroxyethyl)-2-(2-oxopropoxycarbonyl)ethylamine,
N,N-bis(2-acetoxyethyl)-2-(2-oxopropoxycarbonyl)ethylamine,
N,N-bis(2-hydroxyethyl)-2-(tetrahydrofurfuryloxycarbonyl)ethylamine,
N,N-bis(2-acetoxyethyl)-2-(tetrahydrofurfuryloxycarbonyl)ethylamine,
N,N-bis(2-hydroxyethyl)-2-[(2-oxotetrahydrofuran-3-yl)oxycarbonyl]ethyla-
mine,
N,N-bis(2-acetoxyethyl)-2-[(2-oxotetrahydrofuran-3-yl)oxycarbonyl]ethyla-
mine,
N,N-bis(2-hydroxyethyl)-2-(4-hydroxybutoxycarbonyl)ethylamine,
N,N-bis(2-formyloxyethyl)-2-(4-formyloxybutoxycarbonyl)ethylamine,
N,N-bis(2-formyloxyethyl)-2-(2-formyloxyethoxycarbonyl)ethylamine,
N,N-bis(2-methoxyethyl)-2-(methoxycarbonyl)ethylamine,
N-(2-hydroxyethyl)-bis[2-(methoxycarbonyl)ethyl]amine,
N-(2-acetoxyethyl)-bis[2-(methoxycarbonyl)ethyl]amine,
N-(2-hydroxyethyl)-bis[2-(ethoxycarbonyl)ethyl]amine,
N-(2-acetoxyethyl)-bis[2-(ethoxycarbonyl)ethyl]amine,
N-(3-hydroxy-1-propyl)-bis[2-(methoxycarbonyl)ethyl]amine,
N-(3-acetoxy-1-propyl)-bis[2-(methoxycarbonyl)ethyl]amine,
N-(2-methoxyethyl)-bis[2-(methoxycarbonyl)ethyl]amine,
N-butyl-bis[2-(methoxycarbonyl)ethyl]amine,
N-butyl-bis[2-(2-methoxyethoxycarbonyl)ethyl]amine,
N-methyl-bis(2-acetoxyethyl)amine,
N-ethyl-bis(2-acetoxyethyl)amine,
N-methyl-bis(2-pivaloyloxyethyl)amine,
N-ethyl-bis[2-(methoxycarbonyloxy)ethyl]amine,
N-ethyl-bis[2-(tert-butoxycarbonyloxy)ethyl]amine,
tris(methoxycarbonylmethyl)amine,
tris(ethoxycarbonylmethyl)amine,
N-butyl-bis(methoxycarbonylmethyl)amine,
N-hexyl-bis(methoxycarbonylmethyl)amine, and
.beta.-(diethylamino)-.delta.-valerolactone.
[0129] Also useful are one or more of cyclic structure-bearing
basic compounds having the following general formula (B)-2.
##STR43## Herein X is as defined above, and R.sup.307 is a straight
or branched alkylene group of 2 to 20 carbon atoms which may
contain one or more carbonyl, ether, ester or sulfide groups.
[0130] Illustrative examples of the cyclic structure-bearing basic
compounds having formula (B)-2 include
1-[2-(methoxymethoxy)ethyl]pyrrolidine,
1-[2-(methoxymethoxy)ethyl]piperidine,
4-[2-(methoxymethoxy)ethyl]morpholine,
1-[2-[(2-methoxyethoxy)methoxy]ethyl]pyrrolidine,
1-[2-[(2-methoxyethoxy)methoxy]ethyl]piperidine,
4-[2-[(2-methoxyethoxy)methoxy]ethyl]morpholine,
2-(1-pyrrolidinyl)ethyl acetate, 2-piperidinoethyl acetate,
2-morpholinoethyl acetate, 2-(1-pyrrolidinyl)ethyl formate,
2-piperidinoethyl propionate,
2-morpholinoethyl acetoxyacetate,
2-(1-pyrrolidinyl)ethyl methoxyacetate,
4-[2-(methoxycarbonyloxy)ethyl]morpholine,
1-[2-(t-butoxycarbonyloxy)ethyl]piperidine,
4-[2-(2-methoxyethoxycarbonyloxy)ethyl]morpholine,
methyl 3-(1-pyrrolidinyl)propionate,
methyl 3-piperidinopropionate,
methyl 3-morpholinopropionate,
methyl 3-(thiomorpholino)propionate,
methyl 2-methyl-3-(1-pyrrolidinyl)propionate,
ethyl 3-morpholinopropionate,
methoxycarbonylmethyl 3-piperidinopropionate,
2-hydroxyethyl 3-(1-pyrrolidinyl)propionate,
2-acetoxyethyl 3-morpholinopropionate,
2-oxotetrahydrofuran-3-yl 3-(1-pyrrolidinyl)propionate,
tetrahydrofurfuryl 3-morpholinopropionate,
glycidyl 3-piperidinopropionate,
2-methoxyethyl 3-morpholinopropionate,
2-(2-methoxyethoxy)ethyl 3-(1-pyrrolidinyl)propionate,
butyl 3-morpholinopropionate,
cyclohexyl 3-piperidinopropionate,
.alpha.-(1-pyrrolidinyl)methyl-y-butyrolactone,
.beta.-piperidino-.gamma.-butyrolactone,
.beta.-morpholino-.delta.-valerolactone,
methyl 1-pyrrolidinylacetate, methyl piperidinoacetate,
methyl morpholinoacetate, methyl thiomorpholinoacetate,
ethyl 1-pyrrolidinylacetate, and
2-methoxyethyl morpholinoacetate.
[0131] Also, one or more of cyano-bearing basic compounds having
the following general formulae (B)-3 to (B)-6 may be blended.
##STR44## Herein, X, R.sup.307 and n are as defined above, and
R.sup.308 and R.sup.309 are each independently a straight or
branched alkylene group of 1 to 4 carbon atoms.
[0132] Illustrative examples of the cyano-bearing basic compounds
having formulae (B)-3 to (B)-6 include
3-(diethylamino)propiononitrile,
N,N-bis(2-hydroxyethyl)-3-aminopropiononitrile,
N,N-bis(2-acetoxyethyl)-3-aminopropiononitrile,
N,N-bis(2-formyloxyethyl)-3-aminopropiononitrile,
N,N-bis(2-methoxyethyl)-3-aminopropiononitrile,
N,N-bis[2-(methoxymethoxy)ethyl]-3-aminopropiononitrile,
methyl N-(2-cyanoethyl)-N-(2-methoxyethyl)-3-aminopropionate,
methyl N-(2-cyanoethyl)-N-(2-hydroxyethyl)-3-aminopropionate,
methyl N-(2-acetoxyethyl)-N-(2-cyanoethyl)-3-aminopropionate,
N-(2-cyanoethyl)-N-ethyl-3-aminopropiononitrile,
N-(2-cyanoethyl)-N-(2-hydroxyethyl)-3-aminopropiononitrile,
N-(2-acetoxyethyl)-N-(2-cyanoethyl)-3-aminopropiononitrile,
N-(2-cyanoethyl)-N-(2-formyloxyethyl)-3-aminopropiononitrile,
N-(2-cyanoethyl)-N-(2-methoxyethyl)-3-aminopropiononitrile,
N-(2-cyanoethyl)-N-[2-(methoxymethoxy)ethyl]-3-aminopropiononitrile,
N-(2-cyanoethyl)-N-(3-hydroxy-1-propyl)-3-aminopropiononitrile,
N-(3-acetoxy-1-propyl)-N-(2-cyanoethyl)-3-aminopropiononitrile,
N-(2-cyanoethyl)-N-(3-formyloxy-1-propyl)-3-aminopropiononitrile,
N-(2-cyanoethyl)-N-tetrahydrofurfuryl-3-aminopropiononitrile,
N,N-bis(2-cyanoethyl)-3-aminopropiononitrile,
diethylaminoacetonitrile,
N,N-bis(2-hydroxyethyl)aminoacetonitrile,
N,N-bis(2-acetoxyethyl)aminoacetonitrile,
N,N-bis(2-formyloxyethyl)aminoacetonitrile,
N,N-bis(2-methoxyethyl)aminoacetonitrile,
N,N-bis[2-(methoxymethoxy)ethyl]aminoacetonitrile,
methyl N-cyanomethyl-N-(2-methoxyethyl)-3-aminopropionate,
methyl N-cyanomethyl-N-(2-hydroxyethyl)-3-aminopropionate,
methyl N-(2-acetoxyethyl)-N-cyanomethyl-3-aminopropionate,
N-cyanomethyl-N-(2-hydroxyethyl)aminoacetonitrile,
N-(2-acetoxyethyl)-N-(cyanomethyl)aminoacetonitrile,
N-cyanomethyl-N-(2-formyloxyethyl)aminoacetonitrile,
N-cyanomethyl-N-(2-methoxyethyl)aminoacetonitrile,
N-cyanomethyl-N-[2-(methoxymethoxy)ethyl]aminoacetonitrile,
N-cyanomethyl-N-(3-hydroxy-1-propyl)aminoacetonitrile,
N-(3-acetoxy-1-propyl)-N-(cyanomethyl)aminoacetonitrile,
N-cyanomethyl-N-(3-formyloxy-1-propyl)aminoacetonitrile,
N,N-bis(cyanomethyl)aminoacetonitrile,
1-pyrrolidinepropiononitrile, 1-piperidinepropiononitrile,
4-morpholinepropiononitrile, 1-pyrrolidineacetonitrile,
1-piperidineacetonitrile, 4-morpholineacetonitrile,
cyanomethyl 3-diethylaminopropionate,
cyanomethyl N,N-bis(2-hydroxyethyl)-3-aminopropionate,
cyanomethyl N,N-bis(2-acetoxyethyl)-3-aminopropionate,
cyanomethyl N,N-bis(2-formyloxyethyl)-3-aminopropionate,
cyanomethyl N,N-bis(2-methoxyethyl)-3-aminopropionate,
cyanomethyl N,N-bis[2-(methoxymethoxy)ethyl]-3-aminopropionate,
2-cyanoethyl 3-diethylaminopropionate,
2-cyanoethyl N,N-bis(2-hydroxyethyl)-3-aminopropionate,
2-cyanoethyl N,N-bis(2-acetoxyethyl)-3-aminopropionate,
2-cyanoethyl N,N-bis(2-formyloxyethyl)-3-aminopropionate,
2-cyanoethyl N,N-bis(2-methoxyethyl)-3-aminopropionate,
2-cyanoethyl
N,N-bis[2-(methoxymethoxy)ethyl]-3-aminopropionate,
cyanomethyl 1-pyrrolidinepropionate,
cyanomethyl 1-piperidinepropionate,
cyanomethyl 4-morpholinepropionate,
2-cyanoethyl 1-pyrrolidinepropionate,
2-cyanoethyl 1-piperidinepropionate, and
2-cyanoethyl 4-morpholinepropionate.
[0133] The basic compounds may be used alone or in admixture of two
or more. The basic compound is preferably formulated in an amount
of 0.001 to 2 parts, and especially 0.01 to 1 part by weight, per
100 parts by weight of the entire base resin. Less than 0.001 part
of the basic compound achieves no or little addition effect whereas
more than 2 parts would result in too low a sensitivity.
[0134] Other Components
[0135] In the resist composition, a compound bearing a
.ident.--C--COOH group in a molecule may be blended. Exemplary,
non-limiting compounds bearing a .ident.--C--COOH group include one
or more compounds selected from Groups I and II below. Including
this compound improves the PED stability of the resist and
ameliorates edge roughness on nitride film substrates.
Group I:
[0136] Compounds in which some or all of the hydrogen atoms on the
phenolic hydroxyl groups of the compounds of general formulas (A1)
to (A10) below have been replaced with --R.sup.401--COOH (wherein
R.sup.401 is a straight or branched alkylene of 1 to 10 carbon
atoms), and in which the molar ratio C/(C+D) of phenolic hydroxyl
groups (C) to .ident.--C--COOH groups (D) in the molecule is from
0.1 to 1.0. ##STR45## ##STR46##
[0137] In these formulas, R.sup.408 is hydrogen or methyl;
R.sup.402 and R.sup.403 are each hydrogen or a straight or branched
alkyl or alkenyl of 1 to 8 carbon atoms; R.sup.404 is hydrogen, a
straight or branched alkyl or alkenyl of 1 to 8 carbon atoms, or a
--(R.sup.409).sub.h--COOR' group (R' being hydrogen or
--R.sup.409--COOH); R.sup.405 is --(CH.sub.2).sub.i-- (wherein i is
2 to 10), an arylene of 6 to 10 carbon atoms, carbonyl, sulfonyl,
an oxygen atom, or a sulfur atom; R.sup.406 is an alkylene of 1 to
10 carbon atoms, an arylene of 6 to 10 carbon atoms, carbonyl,
sulfonyl, an oxygen atom, or a sulfur atom; R.sup.407 is hydrogen,
a straight or branched alkyl or alkenyl of 1 to 8 carbon atoms, or
a hydroxyl-substituted phenyl or naphthyl; R.sup.409 is a straight
or branched alkylene of 1 to 10 carbon atoms; R.sup.410 is
hydrogen, a straight or branched alkyl or alkenyl of 1 to 8 carbon
atoms, or a --R.sup.411--COOH group; R.sup.411 is a straight or
branched alkylene of 1 to 10 carbon atoms; the letter j is an
integer from 0 to 5; u and h are each 0 or 1; s1, t1, s2, t2, s3,
t3, s4, and t4 are each numbers which satisfy s1+t1=8, s2+t2=5,
s3+t3=4, and s4+t4=6, and are such that each phenyl skeleton has at
least one hydroxyl group; .kappa. is a number such that the
compound of formula (A6) may have a weight average molecular weight
of 1,000 to 5,000; and .lamda. is a number such that the compound
of formula (A7) may have a weight average molecular weight of 1,000
to 10,000.
Group II:
[0138] Compounds of general formulas (A11) to (A15) below.
##STR47##
[0139] In these formulas, R.sup.402, R.sup.403, and R.sup.411 are
as defined above; R.sup.412 is hydrogen or hydroxyl; s5 and t5 are
numbers which satisfy s5>0, t5>0, and s5+t5=5; and h' is
equal to 0 or 1.
[0140] Illustrative, non-limiting examples of the compound bearing
a .quadrature.--C--COOH group include compounds of the general
formulas AI-1 to AI-14 and AII-1 to AII-10 below. ##STR48##
##STR49##
[0141] In the above formulas, R'' is hydrogen or a CH.sub.2COOH
group such that the CH.sub.2COOH group accounts for 10 to 100 mol %
of R'' in each compound, .kappa. and .lamda. are as defined above.
##STR50## ##STR51##
[0142] The compound bearing a .ident.--C--COOH group within the
molecule may be used singly or as combinations of two or more
thereof.
[0143] The compound bearing a .ident.--C--COOH group within the
molecule is added in an amount ranging from 0 to 5 parts,
preferably 0.1 to 5 parts, more preferably 0.1 to 3 parts, further
preferably 0.1 to 2 parts, per 100 parts of the base resin. More
than 5 parts of the compound can reduce the resolution of the
resist composition.
[0144] The resist composition of the invention may additionally
include an acetylene alcohol derivative for the purpose of
enhancing the shelf stability. Preferred acetylene alcohol
derivatives are those having the general formula (S1) or (S2)
below. ##STR52##
[0145] In the formulas, R.sup.501, R.sup.502, R.sup.503, R.sup.504,
and R.sup.505 are each hydrogen or a straight, branched, or cyclic
alkyl of 1 to 8 carbon atoms; and X and Y are each 0 or a positive
number, satisfying 0.ltoreq.X.ltoreq.30, 0.ltoreq.Y.ltoreq.30, and
0.ltoreq.X+Y.ltoreq.40.
[0146] Preferable examples of the acetylene alcohol derivative
include Surfynol 61, Surfynol 82, Surfynol 104, Surfynol 104E,
Surfynol 104H, Surfynol 104A, Surfynol TG, Surfynol PC, Surfynol
440, Surfynol 465, and Surfynol 485 from Air Products and Chemicals
Inc., and Surfynol E1004 from Nisshin Chemical Industry Co.
Ltd.
[0147] The acetylene alcohol derivative is preferably added in an
amount of 0.01 to 2% by weight, and more preferably 0.02 to 1% by
weight, per 100% by weight of the resist composition. Less than
0.01% by weight would be ineffective for improving coating
characteristics and shelf stability, whereas more than 2% by weight
would result in a resist having a low resolution.
[0148] The resist composition of the invention may include optional
ingredients, for example, a surfactant which is commonly used for
improving the coating characteristics. Optional ingredients may be
added in conventional amounts so long as this does not compromise
the objects of the invention.
[0149] Nonionic surfactants are preferred, examples of which
include perfluoroalkylpolyoxyethylene ethanols, fluorinated alkyl
esters, perfluoroalkylamine oxides, perfluoroalkyl EO-addition
products, and fluorinated organosiloxane compounds. Useful
surfactants are commercially available under the trade names
Florade FC-430 and FC-431 from Sumitomo 3M, Ltd., Surflon S-141,
S-145, KH-10, KH-20, KH-30 and KH-40 from Asahi Glass Co., Ltd.,
Unidyne DS-401, DS-403 and DS-451 from Daikin Industry Co., Ltd.,
Megaface F-8151 from Dai-Nippon Ink & Chemicals, Inc., and
X-70-092 and X-70-093 from Shin-Etsu Chemical Co., Ltd. Preferred
surfactants are Florade FC-430 from Sumitomo 3M, Ltd., KH-20 and
KH-30 from Asahi Glass Co., Ltd., and X-70-093 from Shin-Etsu
Chemical Co., Ltd.
[0150] Pattern formation using the resist composition of the
invention may be carried out by a known lithographic technique. For
example, the resist composition is applied onto a substrate such as
a silicon wafer by spin coating or the like to form a resist film
having a thickness of 0.2 to 2.0 .mu.m, which is then pre-baked on
a hot plate at 60 to 150.degree. C. for 1 to 10 minutes, and
preferably at 80 to 130.degree. C. for 1 to 5 minutes. A patterning
mask having the desired pattern is then placed over the resist
film, and the film exposed through the mask to an electron beam or
to high-energy radiation such as deep-UV rays, an excimer laser, or
x-rays in a dose of about 1 to 200 mJ/cm.sup.2, and preferably
about 5 to 100 mJ/cm.sup.2, then post-exposure baked (PEB) on a hot
plate at 60 to 150.degree. C. for 1 to 5 minutes, and preferably at
80 to 130.degree. C. for 1 to 3 minutes. Finally, development is
carried out using as the developer an aqueous alkali solution, such
as a 0.1 to 5% (preferably 2 to 3%) aqueous solution of
tetramethylammonium hydroxide (TMAH), this being done by a
conventional method such as dipping, puddling, or spraying for a
period of 0.1 to 3 minutes, and preferably 0.5 to 2 minutes. These
steps result in the formation of the desired pattern on the
substrate. Of the various types of high-energy radiation that may
be used, the resist composition of the invention is best suited to
fine pattern formation with, in particular, deep-UV rays having a
wavelength of 248 to 193 nm, an excimer laser, x-rays, or an
electron beam. The desired pattern may not be obtainable outside
the upper and lower limits of the above range.
[0151] The resist composition comprising the polymer as a base
resin is sensitive to high-energy radiation, has excellent
sensitivity, resolution, and etching resistance, and lends itself
to micropatterning with electron beams or deep-UV rays. Especially
because of the minimized absorption at the exposure wavelength of
an ArF or KrF excimer laser, a finely defined pattern having
sidewalls perpendicular to the substrate can easily be formed.
EXAMPLE
[0152] Synthesis Examples and Examples are given below by way of
illustration and not by way of limitation.
Synthesis Example 1
[0153] Ester compounds were synthesized in accordance with the
following formulation.
Synthesis Example 1-1
Synthesis of Monomer 1
[0154] A flask was charged with 13.6 g of magnesium and 300 ml of
tetrahydrofuran, to which 60.3 g of 1,4-dibromobutane was added
dropwise at 50.degree. C. After the completion of dropwise
addition, the solution was stirred at 60.degree. C. for one hour.
To the solution below 40.degree. C., 31.0 g of ethyl
tetrahydrofurancarboxylate was added dropwise. The solution was
stirred at room temperature for one hour, after which an aqueous
solution of ammonium chloride was added for hydrolysis. Ordinary
post-treatment yielded 30.2 g of
1-(2-tetrahydrofuranyl)cyclopentanol.
[0155] In 80 ml of toluene were dissolved 16.8 g of
1-(2-tetrahydrofuranyl)cyclopentanol, 13.1 g of triethylamine, and
0.5 g of 4-(N,N-dimethylamino)pyridine. Then 10.7 g of acrylic
chloride was added to the solution at 50.degree. C., which was
stirred at the temperature for one hour. Water, 50 ml, was added to
the solution below 30.degree. C., followed by ordinary
post-treatment. Vacuum distillation yielded 18.1 g of
1-(2-tetrahydrofuranyl)cyclopentyl acrylate. The two-step yield was
80%.
boiling point: 84-86.degree. C./86 Pa
IR (thin film): .nu.=2954, 2871, 1720, 1635, 1619, 1450, 1402,
1298, 1207, 1170, 1074, 1049, 983, 811 cm.sup.-1
.sup.1H-NMR (300 MHz in CDCl.sub.3): .delta.=1.49-2.25 (12H, m),
3.70-3.92 (2H, m), 4.57 (1H, t), 5.72 (1H, dd), 6.04 (1H, dd), 6.29
(1H, dd) ppm
Synthesis Example 1-2
Synthesis of Monomer 2
[0156] A flask was charged with 240 ml of a solution of 1M
methylmagnesium chloride in tetrahydrofuran, to which 15.6 g of
methyl 7-oxa-2-norbornanecarboxylate was added dropwise below
40.degree. C. The solution was stirred at room temperature for one
hour, after which an aqueous solution of ammonium chloride was
added for hydrolysis. Ordinary post-treatment yielded 14.8 g of
2-(7-oxanorbornan-2-yl)-2-propanol.
[0157] In 80 ml of toluene were dissolved 12.5 g of
2-(7-oxanorbornan-2-yl)-2-propanol, 12.1 g of triethylamine, and
0.4 g of 4-(N,N-dimethylamino)pyridine. Then 9.1 g of acrylic
chloride was added to the solution at 50.degree. C., which was
stirred at the temperature for one hour. Water, 50 ml, was added to
the solution below 30.degree. C., followed by ordinary
post-treatment. Vacuum distillation yielded 13.8 g of
2-(7-oxanorbornan-2-yl)-2-propyl acrylate. The two-step yield was
82%.
boiling point: 86-88.degree. C./40 Pa
IR (thin film): .nu.=2978, 2950, 2873, 1720, 1635, 1467, 1452,
1402, 1367, 1299, 1232, 1207, 1166, 1136, 1045, 998, 930, 887, 847,
811, 777 cm.sup.-1
.sup.1H-NMR of major isomer (300 MHz in CDCl.sub.3):
.delta.=1.41-1.93 {11H, m including 1.53 (3H, s) and 1.61 (3H, s)},
2.07-2.18 (2H, m), 4.47 (1H, t), 4.58 (1H, t), 5.75 (1H, dd), 6.03
(1H, dd), 6.31 (1H, dd) ppm
Synthesis Example 1-3
Synthesis of Monomer 3
[0158] The procedure of Synthesis Example 1-2 was repeated except
that methacrylic chloride was used instead of acrylic chloride,
obtaining 2-(7-oxanorbornan-2-yl)-2-propyl methacrylate. The
two-step yield was 76%.
boiling point: 87-88.degree. C./27 Pa
IR (thin film): .nu.=2977, 2952, 2910, 2873, 1712, 1637, 1469,
1452, 1400, 1384, 1367, 1326, 1305, 1240, 1207, 1180, 1159, 1133,
1029, 1000, 973, 931, 887, 848, 815, 783, 777 cm.sup.-1
.sup.1H-NMR of major isomer (300 MHz in CDCl.sub.3):
.delta.=1.46-1.68{9H, m including 1.52 (3H, s) and 1.62 (3H, s)},
1.69-1.82 (1H, m), 1.83-1.93 (4H, m), 2.08-2.18 (2H, m), 4.48 (1H,
t), 4.58 (1H, t), 5.50 (1H, m), 5.99 (1H, m) ppm
Synthesis Example 1-4
Synthesis of Monomer 4
[0159] A flask was charged with 14.6 g of magnesium and 270 ml of
tetrahydrofuran, to which 64.8 g of 1,4-dibromobutane was added
dropwise at 50.degree. C. After the completion of dropwise
addition, the solution was stirred at 60.degree. C. for one hour.
To the solution below 40.degree. C., 39.0 g of methyl
7-oxa-2-norbornanecarboxylate was added dropwise. The solution was
stirred at room temperature for one hour, after which an aqueous
solution of ammonium chloride was added for hydrolysis. Ordinary
post-treatment yielded 43.7 g of
1-(7-oxanorbornan-2-yl)cyclopentanol.
[0160] In 80 ml of toluene were dissolved 18.2 g of
1-(7-oxanorbornan-2-yl)cyclopentanol, 15.2 g of triethylamine, and
0.5 g of 4-(N,N-dimethylamino)pyridine. Then 12.5 g of acrylic
chloride was added to the solution at 50.degree. C., which was
stirred at the temperature for one hour. Water, 50 ml, was added to
the solution below 30.degree. C., followed by ordinary
post-treatment. Vacuum distillation yielded 19.7 g of
1-(7-oxanorbornan-2-yl)cyclopentyl acrylate. The two-step yield was
84%.
boiling point: 95-98.degree. C./29 Pa
IR (thin film): .nu.=2960, 2873, 1720, 1633, 1619, 1469, 1450,
1402, 1332, 1297, 1280, 1197, 1168, 1120, 1045, 998, 985, 962, 944,
881, 811 cm.sup.-1
.sup.1H-NMR of major isomer (600 MHz in CDCl.sub.3): .delta.=1.31
(1H, dd), 1.41-1.48 (1H, m), 1.52-1.93 (9H, m), 1.99-2.05 (1H, m),
2.22-2.26 (1H, m), 2.35-2.43 (1H, m), 2.75-2.81 (1H, m), 4.39 (1H,
t), 4.57 (1H, t), 5.75 (1H, dd), 6.04 (1H, dd), 6.31 (1H, dd)
ppm
Synthesis Example 1-5
Synthesis of Monomer 5
[0161] The procedure of Synthesis Example 1-4 was repeated except
that methacrylic chloride was used instead of acrylic chloride,
obtaining 1-(7-oxanorbornan-2-yl)cyclopentyl methacrylate. The
two-step yield was 73%.
boiling point: 94-96.degree. C./13 Pa
IR (thin film): .nu.=2975, 2956, 2873, 1712, 1637, 1469, 1450,
1400, 1376, 1328, 1303, 1270, 1180, 1159, 1002, 987, 939, 883, 848,
815 cm.sup.-1
.sup.1H-NMR of major isomer (300 MHz in CDCl.sub.3): .delta.=1.30
(1H, dd), 1.41-1.50 (1H, m), 1.52-2.07 (13H, m), 2.16-2.18 (1H, m),
2.35-2.47 (1H, m), 2.78-2.89 (1H, m), 4.38 (1H, t), 4.57 (1H, t),
5.49 (1H, m), 5.99 (1H, m) ppm
Synthesis Example 1-6
Synthesis of Monomer 6
[0162] Monomer 1, 29.5 g, was dissolved in 30 ml of toluene, to
which 11.6 g of cyclopentadiene was added dropwise below 30.degree.
C. The solution was stirred at 50.degree. C. for 10 hours. Vacuum
distillation yielded 37.1 g of 1-(2-tetrahydrofuranyl)-cyclopentyl
5-norbornene-2-carboxylate. The yield was 96%.
boiling point: 116-118.degree. C./33 Pa
IR (thin film): .nu.=2971, 2871, 1727, 1448, 1336, 1270, 1232,
1203, 1167, 1108, 1072, 1024, 995, 937, 865, 839, 711 cm.sup.-1
.sup.1H-NMR of major isomer (300 MHz in CDCl.sub.3):
.delta.=1.20-2.25 (17H, m), 2.81-2.94 (2H, m), 3.16(1H, s),
3.68-3.89 (2H, m), 4.47 (1H, t), 5.86-5.97 (1H, m), 6.14-6.22 (1H,
m) ppm
Synthesis Example 1-7
Synthesis of Monomer 7
[0163] The procedure of Synthesis Example 1-6 was repeated except
that Monomer 2 was used instead of Monomer 1, obtaining
2-(7-oxanorbornan-2-yl)-2-propyl 5-norbornene-2-carboxylate. The
yield was 95%.
boiling point: 120-122.degree. C./13 Pa
IR (thin film): .nu.=3060, 2973, 2946, 2871, 1727, 1463, 1450,
1382, 1365, 1336, 1301, 1272, 1253, 1230, 1205, 1187, 1164, 1133,
1108, 1027, 998, 973, 931, 917, 887, 838, 815, 709 cm.sup.-1
.sup.1H-NMR of major isomer (600 MHz in CDCl.sub.3): .delta.=1.27
(1H, t), 1.35-1.67 (11H, m), 1.72-1.91 (3H, m), 2.05-2.24 (2H, m),
2.88-2.91 (2H, m), 3.18 (1H, s), 4.46 (1H, t), 4.57-4.61 (1H, m),
5.88-5.95 (1H, m), 6.18-6.21 (1H, m) ppm
Synthesis Example 1-8
Synthesis of Monomer 8
[0164] The procedure of Synthesis Example 1-6 was repeated except
that Monomer 4 was used instead of Monomer 1, obtaining
1-(7-oxanorbornan-2-yl)cyclopentyl 5-norbornene-2-carboxylate. The
yield was 93%.
boiling point: 132-135.degree. C./13 Pa
IR (thin film): .nu.=3060, 2973, 2871, 1725, 1471, 1448, 1334,
1270, 1230, 1191, 1164, 1132, 1108, 1022, 1000, 941, 883, 838, 815,
709 cm.sup.-1
[0165] .sup.1H-NMR of major isomer (600 MHz in CDCl.sub.3):
.delta.=1.24-1.33 (4H, m), 1.47-1.69 (6H, m), 1.74-1.92 (5H, m),
2.01-2.19 (2H, m), 2.23-2.33 (1H, m), 2.66-2.71 (1H, m), 2.87-2.91
(2H, m), 3.17 (1H, s), 4.36-4.40 (1H, m), 4.54-4.59 (1H, m),
5.90-5.95 (1H, m), 6.17-6.21 (1H, m) ppm ##STR53## ##STR54##
Synthesis Example 2
[0166] Polymers within the scope of the invention were synthesized
according to the following formulation.
Synthesis Example 2-1
Synthesis of Polymer 1
[0167] To 1500 g of tetrahydrofuran were added 78.5 g of Monomer 1,
70.9 g of hydroxyadamantyl methacrylate, and 77.8 g of
4-oxatricyclo[4.2.1.0.sup.3,7]nonan-5-on-2-yl methacrylate. The
reaction mixture was heated at 60.degree. C., combined with 6.4 g
of 2,2'-azobis(2,4-dimethylvaleronitrile), and then stirred at
60.degree. C. for 15 hours. After cooling to room temperature, the
reaction solution was added dropwise to 9 liters of methanol under
vigorous stirring. The resulting solids were collected by
filtration and vacuum dried at 40.degree. C. for 15 hours. There
was obtained 209 g of a polymer in white powder solid form,
designated Polymer 1. The yield was 92%. Note that Mw is a weight
average molecular weight as measured by gel permeation
chromatography (GPC) using polystyrene standards.
Synthesis Examples 2-2 to 2-7
Synthesis of Polymers 2 to 7
[0168] Polymers 2 to 7 were synthesized by the same procedure as
above or a well-known procedure. ##STR55## ##STR56## ##STR57##
EXAMPLE
[0169] Resist compositions were formulated using the inventive
polymers as a base resin and examined for line density dependency
and resolution.
Examples 1-7 & Comparative Examples 1-2
[0170] Resist compositions were prepared by dissolving the
inventive polymers (Polymers 1 to 7) or comparative polymers
(Polymers 8 to 9 shown below), a photoacid generator, and a basic
compound in a solvent in accordance with the formulation shown in
Table 1. These compositions were each filtered through a Teflon
filter (pore diameter 0.2 .mu.m), thereby giving resist solutions.
##STR58##
[0171] These resist solutions were spin-coated onto silicon wafers
on which an anti-reflection film (AR-19 by Shipley) of 82 nm thick
had been coated and baked at 200.degree. C. for 60 seconds, then
baked on a hot plate at 130.degree. C. for 90 seconds to give
resist films having a thickness of 0.3 .mu.m. The resist films were
exposed using an ArF excimer laser stepper (Nikon Corporation; NA
0.68, .sigma.0.75), then heat treated at 110.degree. C. for 90
seconds, and puddle developed with a solution of 2.38%
tetramethylammonium hydroxide in water for 30 seconds, thereby
giving line-and-space patterns. The developed wafers were cut, and
the cross section was observed under a sectional scanning electron
microscope (SEM). The optimum exposure (Eop, mJ/cm2) was defined as
the exposure which provided a 1:1 resolution at the top and bottom
of a 0.13 .mu.m line-and-space pattern. The resolution of the
resist under evaluation was defined as the minimum line width
(.mu.m) of the lines and spaces that separated at this exposure.
Measured for evaluating line density dependency was the line width
of line-and-space 1:10 solitary lines at the same exposure. The
line width of group lines minus the line width of solitary lines is
the dimensional difference (nm) between sparse and dense patterns.
Also the shape of the resist pattern was classified into
rectangular, rounded head, T-top, forward taper or reverse
taper.
[0172] The composition and test results of the resist materials in
Examples and Comparative Examples are shown in Table 1. The
photoacid generator, basic compound and solvent used are as
follows. It is noted that the solvent contained 0.01% by weight of
surfactant FC-430 (Sumitomo 3M Co., Ltd.).
TPSNf: triphenylsulfonium nonafluorobutanesulfonate
TMMEA: trismethoxymethoxyethylamine
[0173] PGMEA: propylene glycol monomethyl ether acetate
TABLE-US-00001 TABLE 1 Photoacid Basic Dimensional Resin generator
compound Solvent Eop Resolution difference (pbw) (pbw) (pbw) (pbw)
(mJ/cm.sup.2) (.mu.m) (nm) Shape Example 1-1 Polymer 1 TPSNf TMMEA
PGMEA 25 0.11 5 rectangular (80) (1.090) (0.236) (480) 1-2 Polymer
2 TPSNf TMMEA PGMEA 22 0.11 5 rectangular (80) (1.090) (0.236)
(480) 1-3 Polymer 3 TPSNf TMMEA PGMEA 19 0.11 6 rectangular (80)
(1.090) (0.236) (480) 1-4 Polymer 4 TPSNf TMMEA PGMEA 21 0.11 6
rectangular (80) (1.090) (0.236) (480) 1-5 Polymer 5 TPSNf TMMEA
PGMEA 20 0.11 6 rectangular (80) (1.090) (0.236) (480) 1-6 Polymer
6 TPSNf TMMEA PGMEA 28 0.11 6 rectangular (80) (1.090) (0.236)
(480) 1-7 Polymer 7 TPSNf TMMEA PGMEA 18 0.11 5 rectangular (80)
(1.090) (0.236) (480) Comparative 1-1 Polymer 8 TPSNf TMMEA PGMEA
35 0.13 9 T-top Example (80) (1.090) (0.236) (480) 1-2 Polymer 9
TPSNf TMMEA PGMEA 25 0.13 10 forward (80) (1.090) (0.236) (480)
taper
[0174] It is seen from Table 1 that using the polymers within the
scope of the invention, resist compositions having a high
sensitivity, high resolution and minimized line density dependency
are formulated.
[0175] Japanese Patent Application No. 2002-285161 is incorporated
herein by reference.
[0176] Although some preferred embodiments have been described,
many modifications and variations may be made thereto in light of
the above teachings. It is therefore to be understood that the
invention may be practiced otherwise than as specifically described
without departing from the scope of the appended claims.
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