U.S. patent application number 12/321091 was filed with the patent office on 2010-03-04 for organic anti-reflective layer composition containing ring-opened phthalic anhydride and method for preparation thereof.
This patent application is currently assigned to Korea Kumho Petrochemical Co., Ltd.. Invention is credited to Shin-Hyo Bae, Seung-Duk Cho, Seung-Hee Hong, Jong-Don Lee, Jun-Ho Lee.
Application Number | 20100055408 12/321091 |
Document ID | / |
Family ID | 41725878 |
Filed Date | 2010-03-04 |
United States Patent
Application |
20100055408 |
Kind Code |
A1 |
Lee; Jong-Don ; et
al. |
March 4, 2010 |
Organic anti-reflective layer composition containing ring-opened
phthalic anhydride and method for preparation thereof
Abstract
A light absorbent for forming an organic anti-reflective layer,
represented by the following formula 1 or formula 2, is provided:
##STR00001## ##STR00002## wherein A represents a substituted or
unsubstituted, linear or branched, saturated tetravalent
hydrocarbon group, a substituted or unsubstituted, linear or
branched, saturated hydrocarbon group and containing one or more
heteroatoms, a substituted or unsubstituted aromatic group, a
substituted or unsubstituted heteroaromatic group, a substituted or
unsubstituted alicyclic group, a substituted or unsubstituted
heteroalicyclic group, a substituted or unsubstituted diaryl ether,
a substituted or unsubstituted diaryl sulfide, a substituted or
unsubstituted diaryl sulfoxide, a substituted or unsubstituted
diaryl ketone, or a substituted or unsubstituted diaryl bisphenol
A; R.sub.1, R.sub.2, and R.sub.3 each independently represent a
hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl
group a substituted or unsubstituted aryl group, a substituted or
unsubstituted acetal group, or a substituted or unsubstituted
hydroxyl group; and n is an integer from 2 to 500.
Inventors: |
Lee; Jong-Don; (Asan-si,
KR) ; Lee; Jun-Ho; (Asan-si, KR) ; Bae;
Shin-Hyo; (Asan-si, KR) ; Hong; Seung-Hee;
(Asan-si, KR) ; Cho; Seung-Duk; (Asan-si,
KR) |
Correspondence
Address: |
Davidson, Davidson & Kappel, LLC
485 7th Avenue, 14th Floor
New York
NY
10018
US
|
Assignee: |
Korea Kumho Petrochemical Co.,
Ltd.
Seoul
KR
|
Family ID: |
41725878 |
Appl. No.: |
12/321091 |
Filed: |
January 15, 2009 |
Current U.S.
Class: |
428/172 ;
257/E21.215; 438/689; 524/155; 524/288; 524/289; 524/291; 524/294;
560/11; 560/17; 560/61; 560/83; 560/85 |
Current CPC
Class: |
Y10T 428/24612 20150115;
C07C 69/92 20130101; C07C 2602/44 20170501; C07C 69/76 20130101;
C07C 317/44 20130101; C07C 323/62 20130101; C07C 69/753 20130101;
G03F 7/091 20130101 |
Class at
Publication: |
428/172 ; 560/85;
560/61; 560/17; 560/11; 560/83; 524/294; 524/291; 524/155; 524/289;
524/288; 438/689; 257/E21.215 |
International
Class: |
B32B 3/10 20060101
B32B003/10; C07C 69/76 20060101 C07C069/76; C08K 5/12 20060101
C08K005/12; C08K 5/41 20060101 C08K005/41; C08K 5/36 20060101
C08K005/36; H01L 21/306 20060101 H01L021/306 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 26, 2008 |
KR |
10-2008-0083295 |
Claims
1. A light absorbent for forming an organic anti-reflective layer,
represented by the following formula 1: ##STR00025## wherein A
represents a substituted or unsubstituted, linear or branched,
saturated tetravalent hydrocarbon group having 1 to 20 carbon
atoms, a substituted or unsubstituted, linear or branched,
saturated hydrocarbon group having 1 to 20 carbon atoms and
containing one or more heteroatoms, a substituted or unsubstituted
aromatic group having 4 to 20 carbon atoms, a substituted or
unsubstituted heteroaromatic group having 3 to 20 carbon atoms, a
substituted or unsubstituted alicyclic group having 4 to 20 carbon
atoms, a substituted or unsubstituted heteroalicyclic group having
3 to 20 carbon atoms, a substituted or unsubstituted diaryl ether
having 3 to 20 carbon atoms, a substituted or unsubstituted diaryl
sulfide having 3 to 20 carbon atoms, a substituted or unsubstituted
diaryl sulfoxide having 3 to 20 carbon atoms, a substituted or
unsubstituted diaryl ketone having 3 to 20 carbon atoms, or a
substituted or unsubstituted diaryl bisphenol A having 3 to 20
carbon atoms; and R.sub.1 and R.sub.2 each independently represent
a hydrogen atom, a halogen atom, a substituted or unsubstituted
alkyl group having 1 to 10 carbon atoms, a substituted or
unsubstituted aryl group having 6 to 14 carbon atoms, a substituted
or unsubstituted acetal group, or a substituted or unsubstituted
hydroxyl group.
2. A light absorbent for forming an organic anti-reflective layer,
represented by the following formula 2: ##STR00026## wherein A
represents a substituted or unsubstituted, linear or branched,
saturated tetravalent hydrocarbon group having 1 to 20 carbon
atoms, a substituted or unsubstituted, linear or branched,
saturated hydrocarbon group having 1 to 20 carbon atoms and
containing one or more heteroatoms, a substituted or unsubstituted
aromatic group having 4 to 20 carbon atoms, a substituted or
unsubstituted heteroaromatic group having 3 to 20 carbon atoms, a
substituted or unsubstituted alicyclic group having 4 to 20 carbon
atoms, a substituted or unsubstituted heteroalicyclic group having
3 to 20 carbon atoms, a substituted or unsubstituted diaryl ether
having 3 to 20 carbon atoms, a substituted or unsubstituted diaryl
sulfide having 3 to 20 carbon atoms, a substituted or unsubstituted
diaryl sulfoxide having 3 to 20 carbon atoms, a substituted or
unsubstituted diaryl ketone having 3 to 20 carbon atoms, or a
substituted or unsubstituted diaryl bisphenol A having 3 to 20
carbon atoms; R.sub.3 represents a hydrogen atom, a halogen atom, a
substituted or unsubstituted alkyl group having 1 to 10 carbon
atoms, a substituted or unsubstituted aryl group having 6 to 14
carbon atoms, a substituted or unsubstituted acetal group, or a
substituted or unsubstituted hydroxyl group; and n is an integer
from 2 to 500.
3. The light absorbent for forming an organic anti-reflective layer
according to claim 1, wherein the light absorbent represented by
the formula 1 is a compound produced by a reaction in the presence
of a base.
4. The light absorbent for forming an organic anti-reflective layer
according to claim 3, wherein the base is a compound selected from
the group consisting of dimethylaminopyridine, pyridine,
1,4-diazabicyclo[2,2,2]octane, 1,5-diazabicyclo[4,3,0]nonane,
triethylamine, 2,6-di-tert-butylpyridine, diisopropylethylamine,
diazabicycloundecene, tetramethylethylenediamine and
tetrabutylammonium bromide.
5. An organic anti-reflective layer composition comprising a light
absorbent represented by the following formula 1 or formula 2, a
polymer, a thermal acid generating agent, a crosslinking agent and
a solvent: ##STR00027## wherein A represents a substituted or
unsubstituted, linear or branched, saturated tetravalent
hydrocarbon group having 1 to 20 carbon atoms, a substituted or
unsubstituted, linear or branched, saturated hydrocarbon group
having 1 to 20 carbon atoms and containing one or more heteroatoms,
a substituted or unsubstituted aromatic group having 4 to 20 carbon
atoms, a substituted or unsubstituted heteroaromatic group having 3
to 20 carbon atoms, a substituted or unsubstituted alicyclic group
having 4 to 20 carbon atoms, a substituted or unsubstituted
heteroalicyclic group having 3 to 20 carbon atoms, a substituted or
unsubstituted diaryl ether having 3 to 20 carbon atoms, a
substituted or unsubstituted diaryl sulfide having 3 to 20 carbon
atoms, a substituted or unsubstituted diaryl sulfoxide having 3 to
20 carbon atoms, a substituted or unsubstituted diaryl ketone
having 3 to 20 carbon atoms, or a substituted or unsubstituted
diaryl bisphenol A having 3 to 20 carbon atoms; R.sub.1, R.sub.2
and R.sub.3 each independently represent a hydrogen atom, a halogen
atom, a substituted or unsubstituted alkyl group having 1 to 10
carbon atoms, a substituted or unsubstituted aryl group having 6 to
14 carbon atoms, a substituted or unsubstituted acetal group, or a
substituted or unsubstituted hydroxyl group; and n is an integer
from 2 to 500.
6. The organic anti-reflective layer composition according to claim
5, wherein the composition comprises 0.1 to 5% by weight of the
light absorbent, 0.1 to 5% by weight of the polymer, 0.01 to 1% by
weight of the thermal acid generating agent, and 0.05 to 5% by
weight of the crosslinking agent.
7. The organic anti-reflective layer composition according to claim
5, wherein the polymer is a resin having crosslinking sites at the
terminals of the main chain or side chains.
8. The organic anti-reflective layer composition according to claim
5, wherein the crosslinking agent is an aminoplastic compound, a
polyfunctional epoxy resin, an anhydride or a mixture thereof,
which respectively has two or more crosslinkable functional
groups.
9. The organic anti-reflective layer composition according to claim
5, wherein the thermal acid generating agent is toluenesulfonic
acid, an amine salt of toluenesulfonci acid, a pyridine salt of
toluenesulfonic acid, alkylsulfonic acid, an amine salt of
alkylsulfonic acid, or a pyridine salt of alkylsulfonic acid.
10. The organic anti-reflective layer composition according to
claim 5, wherein the solvent is one or more selected from the group
consisting of propylene glycol monomethyl ether (PGME), propylene
glycol monomethyl ether acetate (PGMEA), cyclohexanone, ethyl
lactate, propylene glycol n-propyl ether, dimethylformamide (DMF),
.gamma.-butyrolactone, ethoxyethanol, methoxyethanol, methyl
3-methoxypropionate (MMP) and ethyl 3-ethoxypropionate (EEP).
11. A method for patterning a semiconductor device, the method
comprising: applying the organic anti-reflective layer composition
according to claim 5 on top of a layer to be etched; curing the
applied composition through a baking process, and forming
crosslinking bonds to form an organic anti-reflective layer;
applying a photoresist on top of the organic anti-reflective layer,
and exposing and developing the photoresist to form a photoresist
pattern; and etching the organic anti-reflective layer using the
photoresist pattern as an etching mask, and then etching the layer
to be etched so as to pattern the layer to be etched.
12. The method for patterning a semiconductor device according to
claim 11, wherein the baking process during the curing is carried
out at a temperature of 150.degree. C. to 250.degree. C. for 0.5
minutes or 5 minutes.
13. The method for patterning a semiconductor device according to
claim 11, further comprising a second baking process before or
after exposing during the forming a photoresist pattern.
14. A semiconductor device produced by the method for patterning
according to claim 11.
15. The light absorbent for forming an organic anti-reflective
layer according to claim 2, wherein the light absorbent represented
by the formula 2 is a compound produced by a reaction in the
presence of a base.
16. The light absorbent for forming an organic anti-reflective
layer according to claim 15, wherein the base is a compound
selected from the group consisting of dimethylaminopyridine,
pyridine, 1,4-diazabicyclo[2,2,2]octane,
1,5-diazabicyclo[4,3,0]nonane, triethylamine,
2,6-di-tert-butylpyridine, diisopropylethylamine,
diazabicycloundecene, tetramethylethylenediamine and
tetrabutylammonium bromide.
17. The organic anti-reflective layer composition according to
claim 6, wherein the polymer is a resin having crosslinking sites
at the terminals of the main chain or side chains.
18. The organic anti-reflective layer composition according to
claim 6, wherein the crosslinking agent is an aminoplastic
compound, a polyfunctional epoxy resin, an anhydride or a mixture
thereof, which respectively has two or more crosslinkable
functional groups.
19. The organic anti-reflective layer composition according to
claim 6, wherein the thermal acid generating agent is
toluenesulfonic acid, an amine salt of toluenesulfonci acid, a
pyridine salt of toluenesulfonic acid, alkylsulfonic acid, an amine
salt of alkylsulfonic acid, or a pyridine salt of alkylsulfonic
acid.
20. The organic anti-reflective layer composition according to
claim 6, wherein the solvent is one or more selected from the group
consisting of propylene glycol monomethyl ether (PGME), propylene
glycol monomethyl ether acetate (PGMEA), cyclohexanone, ethyl
lactate, propylene glycol n-propyl ether, dimethylformamide (DMF),
.gamma.-butyrolactone, ethoxyethanol, methoxyethanol, methyl
3-methoxypropionate (MMP) and ethyl 3-ethoxypropionate (EEP).
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a novel light absorbent for
forming an organic anti-reflective layer, which is a ring-opened
phthalic anhydride compound, an organic anti-reflective layer
composition, a method for patterning a semiconductor device using
the organic anti-reflective layer composition, and a semiconductor
device produced by the method for patterning. More particularly,
the present invention relates to a novel light absorbent capable of
being used in producing an organic anti-reflective layer which is
useful for the formation of ultrafine semiconductor patterns using
an ArF excimer laser; an organic anti-reflective layer composition
containing the light absorbent, which prevents reflection from
underneath film layers in lithographic processes, prevents a
stationary wave, and exhibits a high dry etching rate; a method for
patterning a semiconductor device using the organic anti-reflective
layer composition; and a semiconductor device produced by the
method for patterning.
[0003] 2. Description of the Related Art
[0004] Along with the recent high integration of semiconductor
devices, there is a demand for ultrafine patterns with a line width
of 0.10 micrometers or less in the production of ultra LSI and the
like, and a demand also exists for lithographic processes using
light of lower wavelengths in the region of conventionally used
g-ray or i-ray as the exposure wavelength. Accordingly,
microlithographic processes using KrF excimer lasers and ArF
excimer lasers are currently used for the process for producing
semiconductor devices.
[0005] Because the size of patterns of semiconductor devices is
ever decreasing, only when the reflectance is maintained to be at
least less than 1% while the exposure process is carried out, a
uniform pattern can be obtained, and an appropriate process window
can be obtained, so as to attain a desired yield.
[0006] Therefore, technologies of preventing reflection from
underneath film layers and eliminating a stationary wave, by
disposing an organic anti-reflective layer containing organic
molecules which are capable of absorbing light, beneath a
photoresist layer, to thereby control the reflectance so as to
reduce the reflectance at the maximum, have become important.
SUMMARY OF THE INVENTION
[0007] In order to overcome such problems as described above, it is
an object of the present invention to provide a novel light
absorbent which can be used in an organic anti-reflective layer
capable of absorbing reflected light that is generated during
exposure in ultrafine patterning lithographic processes making use
of 193-nm ArF excimer laser, and an organic anti-reflective layer
composition comprising the light absorbent.
[0008] It is another object of the invention to provide a method of
designing the basic structure of an organic anti-reflective layer
to constitute a chemical structure capable of increasing the
etching rate of the organic anti-reflective layer, and producing a
polymer in accordance therewith, to thus produce an organic
anti-reflective layer using the polymer, so that etching processes
can be carried out more smoothly, and to provide a method for
forming a pattern of a semiconductor device using the organic
anti-reflective layer composition, which method is capable of
achieving the formation of excellent ultrafine patterns by
eliminating undercut, footing and the like.
[0009] According to an aspect of the present invention, there is
provided a light absorbent for forming an organic anti-reflective
layer, represented by the following formula 1:
##STR00003##
wherein A represents a substituted or unsubstituted, linear or
branched, saturated tetravalent hydrocarbon group having 1 to 20
carbon atoms, a substituted or unsubstituted, linear or branched,
saturated hydrocarbon group having 1 to 20 carbon atoms and
containing one or more heteroatoms, a substituted or unsubstituted
aromatic group having 4 to 20 carbon atoms, a substituted or
unsubstituted heteroaromatic group having 3 to 20 carbon atoms, a
substituted or unsubstituted alicyclic group having 4 to 20 carbon
atoms, a substituted or unsubstituted heteroalicyclic group having
3 to 20 carbon atoms, a substituted or unsubstituted diaryl ether
having 3 to 20 carbon atoms, a substituted or unsubstituted diaryl
sulfide having 3 to 20 carbon atoms, a substituted or unsubstituted
diaryl sulfoxide having 3 to 20 carbon atoms, a substituted or
unsubstituted diaryl ketone having 3 to 20 carbon atoms, or a
substituted or unsubstituted diaryl bisphenol A having 3 to 20
carbon atoms; and R.sub.1 and R.sub.2 each independently represent
a hydrogen atom, a halogen atom, a substituted or unsubstituted
alkyl group having 1 to 10 carbon atoms, a substituted or
unsubstituted aryl group having 6 to 14 carbon atoms, a substituted
or unsubstituted acetal group, or a substituted or unsubstituted
hydroxyl group.
[0010] According to another aspect of the present invention, there
is provided a light absorbent for forming an organic
anti-reflective layer, represented by the following formula 2:
##STR00004##
wherein A represents a substituted or unsubstituted, linear or
branched, saturated tetravalent hydrocarbon group having 1 to 20
carbon atoms, a substituted or unsubstituted, linear or branched,
saturated hydrocarbon group having 1 to 20 carbon atoms and
containing one or more heteroatoms, a substituted or unsubstituted
aromatic group having 4 to 20 carbon atoms, a substituted or
unsubstituted heteroaromatic group having 3 to 20 carbon atoms, a
substituted or unsubstituted alicyclic group having 4 to 20 carbon
atoms, a substituted or unsubstituted heteroalicyclic group having
3 to 20 carbon atoms, a substituted or unsubstituted diaryl ether
having 3 to 20 carbon atoms, a substituted or unsubstituted diaryl
sulfide having 3 to 20 carbon atoms, a substituted or unsubstituted
diaryl sulfoxide having 3 to 20 carbon atoms, a substituted or
unsubstituted diaryl ketone having 3 to 20 carbon atoms, or a
substituted or unsubstituted diaryl bisphenol A having 3 to 20
carbon atoms; R.sub.3 represents a hydrogen atom, a halogen atom, a
substituted or unsubstituted alkyl group having 1 to 10 carbon
atoms, a substituted or unsubstituted aryl group having 6 to 14
carbon atoms, a substituted or unsubstituted acetal group, or a
substituted or unsubstituted hydroxyl group; and n is an integer
from 2 to 500.
[0011] According to another aspect of the present invention, there
is provided an organic anti-reflective composition comprising the
light absorbent represented by the formula 1 or formula 2, a
polymer, a thermal acid generating agent, a crosslinking agent, and
a solvent.
[0012] According to another aspect of the present invention, there
is provided a method for patterning a semiconductor device, the
method comprising:
[0013] applying the organic anti-reflective layer composition
according to the present invention on top of a layer to be
etched;
[0014] curing the applied composition through a baking process, and
forming crosslinking bonds to form an organic anti-reflective
layer; applying a photoresist on top of the organic anti-reflective
layer, and exposing and developing the photoresist to form a
photoresist pattern; and
[0015] etching the organic anti-reflective layer using the
photoresist pattern as an etching mask, and then etching the layer
to be etched so as to pattern the layer to be etched.
[0016] According to another aspect of the present invention, there
is provided a semiconductor device produced by the method for
patterning according to the present invention.
[0017] The organic anti-reflective layer composition according to
the present invention exhibits excellent adhesiveness and storage
stability, as well as excellent resolution in both C/H patterns and
L/S patterns. The organic anti-reflective layer composition also
has an excellent process window, so that excellent pattern profiles
can be obtained irrespective of the type of the substrate.
[0018] Furthermore, when a pattern is formed using the organic
anti-reflective layer composition, etching of the anti-reflective
layer can be rapidly carried out in ultrafine patterning processes
making use of a 193-nm light source, and as a result, development
of high integration semiconductor devices can be achieved more
actively.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a .sup.1H-NMR spectrum of a copolymer produced
according to an embodiment of the present invention;
[0020] FIG. 2 is a .sup.1H-NMR spectrum of a copolymer produced
according to another embodiment of the present invention;
[0021] FIG. 3 is a .sup.1H-NMR spectrum of a copolymer produced
according to another embodiment of the present invention;
[0022] FIG. 4 is a .sup.1H-NMR spectrum of a copolymer produced
according to another embodiment of the present invention;
[0023] FIG. 5 is a .sup.1H-NMR spectrum of a copolymer produced
according to another embodiment of the present invention;
[0024] FIG. 6 is a .sup.1H-NMR spectrum of a copolymer produced
according to another embodiment of the present invention;
[0025] FIG. 7 is a .sup.1H-NMR spectrum of a copolymer produced
according to another embodiment of the present invention;
[0026] FIG. 8 is a .sup.1H-NMR spectrum of a copolymer produced
according to another embodiment of the present invention; and
[0027] FIG. 9 is a .sup.1H-NMR spectrum of a copolymer produced
according to another embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0028] Hereinafter, the present invention will be described in more
detail.
[0029] According to an aspect of the present invention, a
ring-opened phthalic anhydride represented by the following formula
1, which serves as a light absorbent for forming an organic
anti-reflective layer, is provided.
##STR00005##
wherein A represents a substituted or unsubstituted, linear or
branched, saturated tetravalent hydrocarbon group having 1 to 20
carbon atoms, a substituted or unsubstituted, linear or branched,
saturated hydrocarbon group having 1 to 20 carbon atoms and
containing one or more heteroatoms, a substituted or unsubstituted
aromatic group having 4 to 20 carbon atoms, a substituted or
unsubstituted heteroaromatic group having 3 to 20 carbon atoms, a
substituted or unsubstituted alicyclic group having 4 to 20 carbon
atoms, a substituted or unsubstituted heteroalicyclic group having
3 to 20 carbon atoms, a substituted or unsubstituted diaryl ether
having 3 to 20 carbon atoms, a substituted or unsubstituted diaryl
sulfide having 3 to 20 carbon atoms, a substituted or unsubstituted
diaryl sulfoxide having 3 to 20 carbon atoms, a substituted or
unsubstituted diaryl ketone having 3 to 20 carbon atoms, or a
substituted or unsubstituted diaryl bisphenol A having 3 to 20
carbon atoms; and R.sub.1 and R.sub.2 each independently represent
a hydrogen atom, a halogen atom, a substituted or unsubstituted
alkyl group having 1 to 10 carbon atoms, a substituted or
unsubstituted aryl group having 6 to 14 carbon atoms, a substituted
or unsubstituted acetal group, or a substituted or unsubstituted
hydroxyl group.
[0030] According to another aspect of the present invention, a
ring-opened phthalic anhydride compound represented by the
following formula 2, which serves as a light absorbent for forming
an organic anti-reflective layer, is provided.
##STR00006##
wherein A represents a substituted or unsubstituted, linear or
branched, saturated tetravalent hydrocarbon group having 1 to 20
carbon atoms, a substituted or unsubstituted, linear or branched,
saturated hydrocarbon group having 1 to 20 carbon atoms and
containing one or more heteroatoms, a substituted or unsubstituted
aromatic group having 4 to 20 carbon atoms, a substituted or
unsubstituted heteroaromatic group having 3 to 20 carbon atoms, a
substituted or unsubstituted alicyclic group having 4 to 20 carbon
atoms, a substituted or unsubstituted heteroalicyclic group having
3 to 20 carbon atoms, a substituted or unsubstituted diaryl ether
having 3 to 20 carbon atoms, a substituted or unsubstituted diaryl
sulfide having 3 to 20 carbon atoms, a substituted or unsubstituted
diaryl sulfoxide having 3 to 20 carbon atoms, a substituted or
unsubstituted diaryl ketone having 3 to 20 carbon atoms, or a
substituted or unsubstituted diaryl bisphenol A having 3 to 20
carbon atoms; R.sub.3 represents a,hydrogen atom, a halogen atom, a
substituted or unsubstituted alkyl group having 1 to 10 carbon
atoms, a substituted or unsubstituted aryl group having 6 to 14
carbon atoms, a substituted or unsubstituted acetal group, or a
substituted or unsubstituted hydroxyl group; and n is an integer
from 2 to 500, and preferably an integer from 2 to 300.
[0031] Preferably, the compound of formula 2 has a weight average
molecular weight of 350 to 100,000, and more preferably 400 to
50,000.
[0032] The light absorbent contained in an organic anti-reflective
layer can be classified into a type in which the light absorbent is
included in a compound in the form of a chemical moiety capable of
absorbing light, and a type in which the light absorbent is
separately present with a polymer incapable of absorbing light.
Typically, the light absorbent is separately used so that the
amount of the light absorbing chemical species can be
controlled.
[0033] The light absorbent of the present invention includes a
benzene chromophore, and contains functional groups for thermal
curing.
[0034] Specifically, since benzene chromophore derivatives may have
widely varying etching properties depending on the structure,
derivatives having various structures have been introduced in the
present invention for the application in the organic
anti-reflective layer composition.
[0035] Upon examining the reaction between the above-described
light absorbent according to the present invention and a thermally
curable compound which is a polymer to be contained in the
anti-reflective layer composition as will be described later, a
carboxylic acid functional group is generated by ring-opening of
the light absorbent by means of an alcohol compound, and this
carboxylic acid functional group reacts with a functional group of
the thermally curable compound, such as acetal, epoxy or
hemiacetal, to form a crosslinked structure.
[0036] The term "substituted" according to the present invention
means that one or more hydrogen atoms in a group may be
respectively substituted with a halogen atom, a hydroxyl group, a
nitro group, a cyano group, an amino group, an amidino group,
hydrazine, hydrazone, a carboxylic acid group or a salt thereof, a
sulfonic acid group or a salt thereof, a phosphoric acid group or a
salt thereof, a C.sub.1-C.sub.10 alkyl group, a C.sub.1-C.sub.10
alkenyl group, a C.sub.1-C.sub.10 alkynyl group, a C.sub.6-C.sub.20
aryl group, a C.sub.7-C.sub.20 arylalkyl group, a C.sub.4-C.sub.20
heteroaryl group or a C.sub.5-C.sub.20 heteroarylalkyl group.
[0037] Specific examples of the light absorbent for forming an
organic anti-reflective layer, represented by the formula 1,
according to the present invention include compounds of the
following formulas 3 to 42.
##STR00007## ##STR00008## ##STR00009## ##STR00010## ##STR00011##
##STR00012## ##STR00013## ##STR00014## ##STR00015## ##STR00016##
##STR00017## ##STR00018## ##STR00019##
[0038] Furthermore, specific examples of the light absorbent for
forming an organic anti-reflective layer, represented by the
formula 2, according to the present invention include compounds of
the following formulas 43 to 60.
##STR00020## ##STR00021## ##STR00022##
[0039] According to an embodiment of the present invention, the
compounds represented by formula 1 of the present invention are
produced by reacting a substituted or unsubstituted benzyl alcohol
compound represented by the following formula 61 with various
dianhydride compounds in the presence of a base, and then
neutralizing the base used with an acid.
##STR00023##
wherein R.sub.4 represents a hydrogen atom, a halogen atom, a
substituted or unsubstituted alkyl group having 1 to 10 carbon
atoms, a substituted or unsubstituted aryl group having 6 to 14
carbon atoms, a substituted or unsubstituted acetal group, or a
substituted or unsubstituted hydroxyl group.
[0040] According to another embodiment of the present invention,
the compounds represented by formula 2 of the present invention can
be produced by reacting a compound represented by the following
formula 62 with various dianhydride compounds.
##STR00024##
wherein R.sub.5 represents a hydrogen atom, a halogen atom, a
substituted or unsubstituted alkyl group having 1 to 10 carbon
atoms, a substituted or unsubstituted aryl group having 6 to 14
carbon atoms, a substituted or unsubstituted acetal group, or a
substituted or unsubstituted hydroxyl group.
[0041] The light absorbent of the present invention can be
synthesized by conventional methods, but preferably, synthesis of
the light absorbent of the present invention is achieved by a
reaction in a basic environment.
[0042] The aforementioned various dianhydrides are advantageous in
that the compounds are highly reactive with alcohols, and have four
reactive groups so that two chromophores can be introduced first
and then two more crosslinking sites can be provided in the
subsequent processes.
[0043] Examples of the base that can be used to provide a basic
environment include dimethylaminopyridine, pyridine,
1,4-diazabicyclo[2,2,2]octane. 1,5-diazabicyclo[4,3,0]nonane,
triethylamine, 2,6-di-tert-butylpyridine, diisopropylethylamine,
diazabicycloundecene, tetramethylethylenediamine,
tetrabutylammonium bromide and the like, and no particular
limitation is posed.
[0044] As for the solvent for synthesis, one or more can be
selected from benzene, toluene, xylene, halogenated benzene,
diethyl ether, tetrahydrofuran, esters, ethers, lactones, ketones
and amides, and used.
[0045] The temperature for synthesis of the compound can be
selected and used in accordance with the solvent, and is usually
5.degree. C. to 200.degree. C., and preferably 20.degree. C. to
100.degree. C.
[0046] According to another aspect of the present invention, an
organic anti-reflective layer composition containing the light
absorbent of the present invention is also provided.
[0047] According to an embodiment of the present invention, the
organic anti-reflective layer composition comprises the light
absorbent of the present invention, a polymer, a thermal acid
generating agent, a crosslinking agent and a solvent.
[0048] A preferable organic anti-reflective layer composition needs
to satisfy the following requirements.
[0049] Firstly, the composition should contain a substance which is
capable of absorbing light in the wavelength region of the light
source for exposure so as to prevent reflection from underneath
film layers.
[0050] Secondly, in a process of laminating an anti-reflective
layer and then laminating a photoresist layer, the anti-reflective
layer should not be dissolved and destroyed by the solvent for the
photoresist. For this reason, the anti-reflective layer should be
designed to have a structure which can be thermally cured, and
during the process of laminating the anti-reflective layer, a
baking process is carried out after coating of the anti-reflective
layer so as to proceed curing.
[0051] Thirdly, the anti-reflective layer should be able to be
etched more rapidly than the photoresist layer on the upper side,
so that the loss of photoresist resulting from etching of
underneath film layers can be reduced.
[0052] Fourthly, the anti-reflective layer composition should not
be reactive to the photoresist on the upper side. Further,
compounds such as amines or acids should be prevented from
migrating to the photoresist layer. This is because these migrating
impurities may cause defects, such as footing or undercut in
particular, in the photoresist pattern.
[0053] Fifthly, the anti-reflective layer composition should have
optical properties which are suitable for various exposure
processes using various substrates, that is, appropriate refractive
index and absorption coefficient, and should have good adhesive
power to the substrate and photoresist layer.
[0054] The organic anti-reflective layer composition according to
the present invention satisfies all of the above-mentioned
requirements.
[0055] Hereinafter, the organic anti-reflective layer composition
according to the present invention will be described in detail.
[0056] The light absorbent is a compound represented by formula 1
or formula 2 as described previously in the above. The polymer to
be contained in the organic anti-reflective layer composition of
the present invention can be obtained by polymerizing an
acrylate-based, maleic anhydride-based, phenol-based or ester-based
monomer, and the polymer is not particularly limited as long as it
is a polymer having crosslinking sites which are capable of
reacting with the light absorbent, at the terminals of the main
chain or side chains.
[0057] An organic anti-reflective layer employing such polymer
acquires resistance to dissolution by solvents, as the composition
applied on a substrate is cured while going through a baking
process.
[0058] Therefore, at the time of applying a photosensitizer after
the lamination of the organic anti-reflective layer, dissolution of
the anti-reflective layer by the solvent of the photosensitizer
does not occur, and stability can be imparted to the
anti-reflective layer.
[0059] The organic anti-reflective layer composition of the present
invention may contain additives in order to facilitate curing of
the light absorbent and polymer and to enhance their performance,
and examples of such additives include a crosslinking agent and a
thermal acid generating agent.
[0060] First, the crosslinking agent is preferably a compound
having at least two or more crosslinkable functional groups, and
examples thereof include aminoplastic compounds, polyfunctional
epoxy resins, mixtures of dianhydrides, and the like.
[0061] The aminoplastic compounds may be exemplified by
dimethoxymethylglycoluril, diethoxymethylglycoluril and mixtures
thereof, diethyldimethylmethylglycoluril,
tetramethoxymethylglycoluril, hexamethoxymethylmelamine resin, and
the like.
[0062] As for the polyfunctional epoxy compounds, it is preferable
to use, for example, MY720, CY179MA, DENACOL and the like, as well
as products equivalent thereto.
[0063] Next, it is preferable to use a thermal acid generating
agent as a catalyst for accelerating the curing reaction. As for
the thermal acid generating agent to be contained in the present
invention, toluenesulfonic acid, amine salts or pyridine salts of
toluenesulfonic acid, alkylsulfonic acid, amine salts or pyridine
salts of alkylsulfonic acid, and the like can also be used.
[0064] As for the organic solvent that can be used in the organic
anti-reflective layer composition of the present invention, it is
preferable to use one or more solvents selected from the group
consisting of propylene glycol monomethyl ether (PGME), propylene
glycol monomethyl ether acetate (PGMEA), cyclohexanone, ethyl
lactate, propylene glycol n-propyl ether, dimethylformamide (DMF),
.gamma.-butyrolactone, ethoxyethanol, methoxyethanol, methyl
3-methoxypropionate (MMP) and ethyl 3-ethoxypropionate (EEP).
[0065] According to another embodiment of the present invention,
the organic anti-reflective layer composition contains the light
absorbent represented by formula 1 or formula 2 in an amount of
preferably 0.1 to 40% by weight, more preferably 0.1 to 15% by
weight, and even more preferably 0.1 to 10% by weight, based on the
whole composition. The polymer is contained in an amount of
preferably 0.1 to 20% by weight based on the whole composition. The
crosslinking agent is contained in an amount of preferably 0.01 to
15% by weight, and more preferably 0.05 to 7% by weight, based on
the whole composition. The thermal acid generating agent is
contained in an amount of 0.01 to 20% by weight, more preferably
0.01 to 10% by weight, and even more preferably 0.02 to 5% by
weight, based on the whole composition. The balance of the contents
in the composition can be constituted of the solvent and other
additional additives which are well known and widely used.
[0066] When the processes for forming an organic anti-reflective
layer are briefly examined, an organic anti-reflective layer
composition containing the constituent components as described
above at the compositional ratios given above is applied on a
wafer, and then a thermal process such as baking is carried out so
that acid is generated from the thermal acid generating agent.
Then, in the presence of the generated acid, a crosslinking
reaction involving the light absorbent represented by formula 1 or
formula 2, the polymer and the crosslinking agent which is used as
an additive, is accelerated, and an organic anti-reflective layer
which is not soluble in organic solvents is formed. Such organic
anti-reflective layer can prevent diffused reflection from the
layers underneath the photoresist layer by absorbing
far-ultraviolet rays which have penetrated through the photoresist
layer and reached the organic anti-reflective layer.
[0067] The method for forming a pattern of a semiconductor device
using the organic anti-reflective layer composition as described
above, comprises applying the organic anti-reflective layer
composition on top of a layer to be etched; curing the applied
composition through a baking process, and forming crosslinking
bonds to form an organic anti-reflective layer; applying a
photoresist on top of the organic anti-reflective layer, and
exposing and developing the photoresist to form a photoresist
pattern; and etching the organic anti-reflective layer using the
photoresist pattern as an etching mask, and then etching the layer
to be etched so as to pattern the layer to be etched.
[0068] In the process of laminating the organic anti-reflective
layer according to the present invention, the baking process can be
carried out preferably at a temperature of 150.degree. C. to
250.degree. C. for 0.5 to 5 minutes, and more preferably for 1
minute to 5 minutes.
[0069] Furthermore, in the patterning method according to the
present invention, an additional baking process can be carried out
again before or after laminating an organic or inorganic
composition of anti-reflective layer or silicone anti-reflective
layer on top of a spin-on carbon hard mask, and such baking process
is preferably carried out at a temperature of 70.degree. C. to
200.degree. C.
[0070] According to another aspect of the present invention, a
semiconductor device produced by the patterning method of the
present invention is provided.
[0071] The present invention will be described specifically by way
of the following Synthesis Examples and Examples. However, the
present invention is not intended to be limited to these Synthesis
Examples and Examples.
[0072] In the following Synthesis Examples 1 to 10, light
absorbents for organic anti-reflective layer were synthesized.
SYNTHESIS EXAMPLE 1
[0073] 50 g of bicycle[2,2,2]octene-2,3,5,6-tetracarboxylic acid
dianhydride, 43.57 g of benzenemethanol, 31.87 g of pyridine and
4.92 g of dimethylaminopyridine were dissolved in 260.73 g of
1,4-dioxane, and then the solution was allowed to react at
80.degree. C. for 24 hours. After completion of the reaction,
formic acid was added dropwise to the reaction solution to
neutralize the solution. Ethyl acetate and distilled water were
added to this reaction product, and the organic layer was
separated. The separated organic layer was subjected to solvent
removal, and then was dissolved again in dioxane. This solution was
dropped in water, and a precipitate thus generated was filtered,
washed several times with distilled water, and then dried, to
obtain 45.62 g (yield=46.6%) of a compound. The .sup.1H-NMR
spectrum of the copolymer produced according to Synthesis Example 1
is presented in FIG. 1.
SYNTHESIS EXAMPLE 2
[0074] 105 g of 4,4'-oxydiphthalic anhydride, 73.21 g of
benzenemethanol, 5.36 g of pyridine, and 8.27 g of
dimethylaminopyridine were dissolved in 450.21 g of 1,4-dioxane,
and then the solution was allowed to react at 80.degree. C. for 24
hours. After completion of the reaction, formic acid was added
dropwise to the reaction solution to neutralize the solution. Ethyl
acetate and distilled water were added to this reaction product,
and the organic layer was separated. The separated organic layer
was subjected to solvent removal, and then was dissolved in
propylene glycol monomethyl ether acetate, to obtain a compound.
The .sup.1H-NMR spectrum of the solid light absorbent produced
according to Synthesis Example 2 is presented in FIG. 2.
SYNTHESIS EXAMPLE 3
[0075] 50 g of 4,4'-(4,4'-isopropylidenediphenoxy)bis(phthalic
anhydride), 19.74 g of benzyl alcohol, 15.2 g of pyridine, and 2.35
g of dimethylaminopyridine were dissolved in 174.56 g of
1,4-dioxane, and then the solution was allowed to react at
80.degree. C. for 24 hours. After completion of the reaction,
formic acid was added dropwise to the reaction solution to
neutralize the solution. Ethyl acetate and distilled water were
added to this reaction product, and the organic layer was
separated. The separated organic layer was subjected to solvent
removal, and then was dissolved in propylene glycol monomethyl
ether acetate, to obtain a compound. The .sup.1H-NMR spectrum of
the solid light absorbent produced according to Synthesis Example 3
is presented in FIG. 3.
SYNTHESIS EXAMPLE 4
[0076] 50 g of benzophenone-3,3',4,4'-tetracarboxylic acid
dianhydride, 33.56 g of benzyl alcohol, 24.55 g of pyridine, and
3.79 g of dimethylaminopyridine were dissolved in 223.8 g of
1,4-dioxane, and then the solution was allowed to react at
80.degree. C. for 24 hours. After completion of the reaction,
formic acid was added dropwise to the reaction solution to
neutralize the solution. Ethyl acetate and distilled water were
added to this reaction product, and the organic layer was
separated. The separated organic layer was subjected to solvent
removal, and then was dissolved in propylene glycol monomethyl
ether acetate, to obtain a compound. The .sup.1H-NMR spectrum of
the solid light absorbent produced according to Synthesis Example 4
is presented in FIG. 4.
SYNTHESIS EXAMPLE 5
[0077] 25 g of 4,4'-(hexafluoroisopropylidene)diphthalic anhydride,
12.17 g of benzyl alcohol, 8.9 g of pyridine, and 1.38 g of
dimethylaminopyridine were dissolved in 94.9 g of 1,4-dioxane, and
then the solution was allowed to react at 80.degree. C. for 24
hours. After completion of the reaction, formic acid was added
dropwise to the reaction solution to neutralize the solution. Ethyl
acetate and distilled water were added to this reaction product,
and the organic layer was separated. The separated organic layer
was subjected to solvent removal, and then was dissolved in
propylene glycol monomethyl ether acetate, to obtain a compound.
The .sup.1H-NMR spectrum of the solid light absorbent produced
according to Synthesis Example 5 is presented in FIG. 5.
SYNTHESIS EXAMPLE 6
[0078] 20 g of 4,4'-(4,4'-isopropylidenediphenoxy)bis(phthalic
anhydride), 5.31 g of benzenedimethanol, 3.04 g of pyridine, and
0.74 g of dimethylaminopyridine were dissolved in 57.64 g of
1,4-dioxane, and then the solution was allowed to react at
80.degree. C. for 24 hours. After completion of the reaction,
formic acid was added dropwise to the reaction solution to
neutralize the solution. Ethyl acetate and distilled water were
added to this reaction product, and the organic layer was
separated. The separated organic layer was subjected to solvent
removal, and then was dissolved in propylene glycol monomethyl
ether acetate, to obtain a compound. The .sup.1H-NMR spectrum of
the solid light absorbent produced according to Synthesis Example 6
is presented in FIG. 6.
SYNTHESIS EXAMPLE 7
[0079] 50 g of 4,4'-(4,4'-isopropylidenediphenoxy)bis(phthalic
anhydride), 27.28 g of 4-(hydroxymethyl)benzoic acid, 15.2 g of
pyridine, and 2.35 g of dimethylaminopyridine were dissolved in
174.56 g of 1,4-dioxane, and then the solution was allowed to react
at 80.degree. C. for 24 hours. After completion of the reaction,
formic acid was added dropwise to the reaction solution to
neutralize the solution. Ethyl acetate and distilled water were
added to this reaction product, and the organic layer was
separated. The separated organic layer was subjected to solvent
removal, and then was dissolved in propylene glycol monomethyl
ether acetate, to obtain a compound. The .sup.1H-NMR spectrum of
the solid light absorbent produced according to Synthesis Example 7
is presented in FIG. 7.
SYNTHESIS EXAMPLE 8
[0080] 50 g of 4,4'-(4,4'-isopropylidenediphenoxy)bis(phthalic
anhydride), 31.39 g of methyl 4-(hydroxymethyl)benzoate, 15.2 g of
pyridine, and 2.35 g of dimethylaminopyridine were dissolved in
174.56 g of 1,4-dioxane, and then the solution was allowed to react
at 80.degree. C. for 24 hours. After completion of the reaction,
formic acid was added dropwise to the reaction solution to
neutralize the solution. Ethyl acetate and distilled water were
added to this reaction product, and the organic layer was
separated. The separated organic layer was subjected to solvent
removal, and then was dissolved in propylene glycol monomethyl
ether acetate, to obtain a compound. The .sup.1H-NMR spectrum of
the solid light absorbent produced according to Synthesis Example 8
is presented in FIG. 8.
SYNTHESIS EXAMPLE 9
[0081] 50 g of 4,4'-(4,4'-isopropylidenediphenoxy)bis(phthalic
anhydride), 23.47 g of 4-methylbenzyl alcohol, 15.2 g of pyridine,
and 2.35 g of dimethylaminopyridine were dissolved in 174.56 g of
1,4-dioxane, and then the solution was allowed to react at
80.degree. C. for 24 hours. After completion of the reaction,
formic acid was added dropwise to the reaction solution to
neutralize the solution. Ethyl acetate and distilled water were
added to this reaction product, and the organic layer was
separated. The separated organic layer was subjected to solvent
removal, and then was dissolved in propylene glycol monomethyl
ether acetate, to obtain a compound. The .sup.1H-NMR spectrum of
the solid light absorbent produced according to Synthesis Example 9
is presented in FIG. 9.
SYNTHESIS EXAMPLE 10
[0082] 50 g of 4,4'-(4,4'-isopropylidenediphenoxy)bis(phthalic
anhydride), 23.85 g of 4-hydroxybenzyl alcohol, 15.2 g of pyridine,
and 2.35 g of dimethylaminopyridine were dissolved in 174.56 g of
1,4-dioxane, and then the solution was allowed to react at
80.degree. C. for 24 hours. After completion of the reaction,
formic acid was added dropwise to the reaction solution to
neutralize the solution. Ethyl acetate and distilled water were
added to this reaction product, and the organic layer was
separated. The separated organic layer was subjected to solvent
removal, and then was dissolved in propylene glycol monomethyl
ether acetate, to obtain a compound. The .sup.1H-NMR spectrum of
the solid light absorbent produced according to Synthesis Example
10 is presented in FIG. 10.
EXAMPLE 1
[0083] Preparation of Organic Anti-Reflective Layer Composition
A
[0084] 4 g of the light absorbent for organic anti-reflective layer
produced in the above Synthesis Example 1, 6 g of an acrylic
polymer, 2 g of tetramethoxymethylglycoluril and 0.2 g of
pyridinium p-toluenesulfonate were dissolved in 987.8 g of
propylene glycol monomethyl ether acetate, and then the solution
was filtered through a membrane filter having a pore size of 0.2
.mu.m, to prepare an organic anti-reflective layer composition
A.
EXAMPLE 2
[0085] Preparation of Organic Anti-Reflective Layer Composition
B
[0086] 4 g of the light absorbent for organic anti-reflective layer
produced in the above Synthesis Example 2, 6 g of an acrylic
polymer, 2 g of tetramethoxymethylglycoluril and 0.2 g of
pyridinium p-toluenesulfonate were dissolved in 987.8 g of
propylene glycol monomethyl ether acetate, and then the solution
was filtered through a membrane filter having a pore size of 0.2
.mu.m, to prepare an organic anti-reflective layer composition
B.
EXAMPLE 3
[0087] Preparation of Organic Anti-Reflective Layer Composition
C
[0088] 4 g of the light absorbent for organic anti-reflective layer
produced in the above Synthesis Example 3, 6 g of an acrylic
polymer, 2 g of tetramethoxymethylglycoluril and 0.2 g of
pyridinium p-toluenesulfonate were dissolved in 987.8 g of
propylene glycol monomethyl ether acetate, and then the solution
was filtered through a membrane filter having a pore size of 0.2
.mu.m, to prepare an organic anti-reflective layer composition
C.
EXAMPLE 4
[0089] Preparation of Organic Anti-Reflective Layer Composition
D
[0090] 4 g of the light absorbent for organic anti-reflective layer
produced in the above Synthesis Example 4, 6 g of an acrylic
polymer, 2 g of tetramethoxymethylglycoluril and 0.2 g of
pyridinium p-toluenesulfonate were dissolved in 987.8 g of
propylene glycol monomethyl ether acetate, and then the solution
was filtered through a membrane filter having a pore size of 0.2
.mu.m, to prepare an organic anti-reflective layer composition
D.
EXAMPLE 5
[0091] Preparation of Organic Anti-Reflective Layer Composition
E
[0092] 4 g of the light absorbent for organic anti-reflective layer
produced in the above Synthesis Example 5, 6 g of an acrylic
polymer, 2 g of tetramethoxymethylglycoluril and 0.2 g of
pyridinium p-toluenesulfonate were dissolved in 987.8 g of
propylene glycol monomethyl ether acetate, and then the solution
was filtered through a membrane filter having a pore size of 0.2
.mu.m, to prepare an organic anti-reflective layer composition
E.
EXAMPLE 6
[0093] Preparation of Organic Anti-Reflective Layer Composition
F
[0094] 4 g of the light absorbent for organic anti-reflective layer
produced in the above Synthesis Example 6, 6 g of an acrylic
polymer, 2 g of tetramethoxymethylglycoluril and 0.2 g of
pyridinium p-toluenesulfonate were dissolved in 987.8 g of
propylene glycol monomethyl ether acetate, and then the solution
was filtered through a membrane filter having a pore size of 0.2
.mu.m, to prepare an organic anti-reflective layer composition
F.
EXAMPLE 7
[0095] Preparation of Organic Anti-Reflective Layer Composition
G
[0096] 4 g of the light absorbent for organic anti-reflective layer
produced in the above Synthesis Example 7, 6 g of an acrylic
polymer, 2 g of tetramethoxymethylglycoluril and 0.2 g of
pyridinium p-toluenesulfonate were dissolved in 987.8 g of
propylene glycol monomethyl ether acetate, and then the solution
was filtered through a membrane filter having a pore size of 0.2
.mu.m, to prepare an organic anti-reflective layer composition
G.
EXAMPLE 8
[0097] Preparation of Organic Anti-Reflective Layer Composition
H
[0098] 4 g of the light absorbent for organic anti-reflective layer
produced in the above Synthesis Example 8, 6 g of an acrylic
polymer, 2 g of tetramethoxymethylglycoluril and 0.2 g of
pyridinium p-toluenesulfonate were dissolved in 987.8 g of
propylene glycol monomethyl ether acetate, and then the solution
was filtered through a membrane filter having a pore size of 0.2
.mu.m, to prepare an organic anti-reflective layer composition
H.
EXAMPLE 9
[0099] Preparation of Organic Anti-Reflective Layer Composition
I
[0100] 4 g of the light absorbent for organic anti-reflective layer
produced in the above Synthesis Example 9, 6 g of an acrylic
polymer, 2 g of tetramethoxymethylglycoluril and 0.2 g of
pyridinium p-toluenesulfonate were dissolved in 987.8 g of
propylene glycol monomethyl ether acetate, and then the solution
was filtered through a membrane filter having a pore size of 0.2
.mu.m, to prepare an organic anti-reflective layer composition
I.
EXAMPLE 10
[0101] Preparation of Organic Anti-Reflective Layer Composition
J
[0102] 4 g of the light absorbent for organic anti-reflective layer
produced in the above Synthesis Example 10, 6 g of an acrylic
polymer, 2 g of tetramethoxymethylglycoluril and 0.2 g of
pyridinium p-toluenesulfonate were dissolved in 987.8 g of
propylene glycol monomethyl ether acetate, and then the solution
was filtered through a membrane filter having a pore size of 0.2
.mu.m, to prepare an organic anti-reflective layer composition
J.
[0103] Results for measurement of properties of organic
anti-reflective layers and formation of photoresist patterns
[0104] 1) Stripping Test
[0105] Each of the organic anti-reflective layer compositions A to
J prepared in Example 1 to 10 was applied on a silicon wafer by
spin coating, and then the coated wafer was baked on a hot plate at
230.degree. C. for 1 minute to form an organic anti-reflective
layer. The thickness of the layer was measured, and the wafer
coated with the organic anti-reflective layer was immersed for 1
minute in ethyl lactate and propylene glycol monomethyl ether,
which are solvents used for the photoresist. Subsequently, the
coated wafer was baked on a hot plate at 100.degree. C. for 1
minute to completely remove the solvents, and then the thickness of
the organic anti-reflective layer was measured again. It was
confirmed that the anti-reflective layer was insoluble in the
solvents.
[0106] 2) Measurement of Optical Properties
[0107] Each of the organic anti-reflective layer compositions A to
J prepared in Example 1 to 10 was applied on a silicon wafer by
spin coating, and then the coated wafer was baked on a hot plate at
230.degree. C. for 1 minute to form an organic anti-reflective
layer. The refractive index (n) at 193 nm and the extinction
coefficient (k) of the anti-reflective layer were measured using a
spectroscopic ellipsometer (J.A. Woollam Co., Inc.). The
measurement results are presented in Table 1.
TABLE-US-00001 TABLE 1 Extinction Thickness of first Refractive
coefficient microthin film Reflectance index (n) (k) (nm) (%)
Example 1 1.62 0.28 33 <0.1 Example 2 1.76 0.28 24 <0.1
Example 3 1.75 0.29 24 <0.1 Example 4 1.79 0.33 22 <0.1
Example 5 1.69 0.37 27 <0.2 Example 6 1.67 0.28 30 <0.1
Example 7 1.65 0.29 31 <0.1 Example 8 1.68 0.29 29 <0.1
Example 9 1.67 0.25 30 <0.1 Example 10 1.66 0.25 31 <0.1
[0108] 3) Simulation of First Microthin Film
[0109] An organic anti-reflective layer was formed using each of
the organic anti-reflective layer compositions A to J prepared in
Example 1 to 10, and then the refractive index (n) at 193 nm and
the extinction coefficient (k) of the anti-reflective layer were
measured using a spectroscopic ellipsometer. Subsequently, the
thickness of the first microthin film, and the reflectance in the
case of using the thickness of the first microthin film were
calculated by performing a simulation using the values of the
refractive index (n) and extinction coefficient (k) obtained from
the measurement. The simulation was related to the reflectance
obtainable in the case where 40 nm of silicon oxynitride was
deposited on the silicon wafer. The software used in the simulation
was KLA Tencor FINDLE Division PROLITH, and the results are
presented in Table 1.
[0110] 4) Formation of Organic Anti-Reflective Layer and
Photoresist Pattern
[0111] Each of the organic anti-reflective layer compositions A to
J prepared in Example 1 to 10 was applied by spin coating on a
silicon wafer deposited with silicon oxynitride, and then the
coated wafer was baked on a hot plate at 230.degree. C. for 1
minute, to form an organic anti-reflective layer. Subsequently, an
ArF photoresist was applied on top of the organic anti-reflective
layer, and then the coated wafer was baked at 100.degree. C. for 60
seconds. Then, the photoresist was exposed using a scanner
equipment, and then the wafer was baked again at 115.degree. C. for
60 seconds. The exposed wafer was developed using a developer
solution containing 2.38% by weight of TMAH, to obtain a final
photoresist pattern. The pattern was of L/S type with a size of 80
nm, and the results are presented in Table 2.
TABLE-US-00002 TABLE 2 Energy Focus margin depth margin (%) (.mu.m)
Shape of pattern Example 1 22 0.4 Perpendicular Example 2 20 0.5
Perpendicular Example 3 23 0.5 Perpendicular Example 4 26 0.3
Perpendicular Example 5 31 0.5 Perpendicular Example 6 28 0.4
Perpendicular Example 7 27 0.4 Perpendicular Example 8 26 0.5
Perpendicular Example 9 28 0.4 Perpendicular Example 10 31 0.3
Perpendicular
* * * * *