PLANARIZI NG COATI NG-FORMI NG COM POSITION AN D M ETHODS FOR MAN U FACTU RI NG PLANARIZI N G COATI NG AN D DEVI CE USI NG TH E SAME [Technical Field]

[0001 ]

The present invention relates to a planarizing coating-forming composition used for forming a pattern by a lithography technique using a photoresist and to a method for manufacturing a planarizing coating using the planarizing coating-forming composition . The present invention also relates to methods for manufacturing a resist pattern and a device such as a semiconductor by a lithography technique using the planarizing coating.

[Background Art]

[0002]

Production processes of devices such as semiconductors generally employ fine processing performed by lithography technology using a photoresist. The fine processing includes the steps of: forming a thin photoresist layer on a semiconductor substrate such as a silicon wafer; covering the layer with a mask pattern corresponding to the pattern of the intended device; exposing the layer with active light such as ultraviolet light through the mask pattern ; developing the exposed layer to obtain a photoresist pattern ; and etching the substrate using the obtained

photoresist pattern as a protective coating, thus forming a fine unevenness corresponding to the above-described pattern . These photolithography steps suffer from reduction in the dimensional accuracy of the photoresist pattern due to the influence of standing waves resulting from reflection of light from the substrate or the influence of diffuse reflection of the exposure light by irregularities of the substrate. To solve this problem, methods of providing a bottom anti-reflective coating have been widely studied . The properties required of such a bottom anti-reflective coating include: having a high absorbance for the radioactive ray used for exposure of the photoresist; being able to prevent a phenomenon such as diffuse reflection so that the cross-section of the photoresist will be vertical to the surface of the substrate after exposure and development; and being insoluble in the solvent contained in the photoresist composition (being less prone to intermixing).

[0003]

Attempts to place a resist bottom coating between a resist layer and a wafer have also been made to achieve good adhesion of the resist layer to the wafer or enable selective etching (Patent Literature 1 ).

[Citation List]

[Patent Literature]

[0004]

[Patent Literature 1 ]

I nternational Publication No. WO 201 3/024779 A1 [Summary of I nvention]

[Technical Problem]

[0005]

The present inventors have considered that etching resistance and gap filling property in a complicated , finely processed substrate (for example, a stepped substrate) are useful for a planarizing coating in a lithography step, made intensive studies, and found a composition to be described below. Further, the present inventors have found that a specific monomer that is polymerized into a coating and exhibits high etching resistance after being applied to a substrate is highly soluble in a specific solvent. The present inventors have focused on the fact that in practically used semiconductors, unlike in test wafers, steps are unevenly distributed so that the distribution of high structures is locally dense or sparse (nonuniform). When a wafer has such a dense region and sparse region, it is difficult for a coating formed from a composition on the wafer to be completely flat, since there occur interaction of the composition , surface tension , and contraction during conversion to the coating. However, the composition discovered by the present inventors yielded high flatness even when formed into a coating on a wafer having a dense region and sparse region as described above.

[Solution to Problem]

[0006]

A planarizing coating-forming composition according to the present invention comprises:

a monomer represented by formula (I ); and

one or more organic solvents comprising a hydroxyl group and an ester-derivative group represented by formula (I I ) in a molar ratio of 23:77 to 77:23.

[0007]

[Formula 1 ]

( I ) [0008]

In formula (I),

An is a direct bond, Ci-6 alkyl, Ce-12 cycloalkyl, or Ce-14 aryl,

Ar2 is Ci-6 alkyl, Ce-12 cycloalkyl, or Ce-14 aryl,

Ri and R2 are each independently C1-6 alkyl, hydroxy, halogen, or cyano,

R3 is hydrogen, C1-6 alkyl, or Ce-14 aryl,

when Ar2 is C1-6 alkyl or Ce-14 aryl and R3 is C1-6 alkyl or Ce-14 aryl, Ar2 and R3 are optionally linked to each other to form a hydrocarbon ring,

r and s are each independently 0, 1, 2, 3, 4, or 5,

at least one of the Ci, C2, and C3 rings each surrounded by the broken line is an aromatic hydrocarbon ring fused with the adjacent aromatic hydrocarbon ring Pi, and

at least one of the C4, C5, and C6 rings each surrounded by the broken line is an aromatic hydrocarbon ring fused with the adjacent aromatic hydrocarbon ring P2.

[0009]

[Formula 2]

[0010]

In formula (II), R4 is a direct bond to a moiety of the organic solvent molecule other than the moiety of formula (II), a methyl, or carbon linked to R6 to form a saturated ring,

R5 is hydrogen, or methoxy-substituted or unsubstituted C1-3 alkyl, and

R6 is a methyl or carbon linked to R4 to form a saturated ring. [001 1 ]

A method for manufacturing a planarizing coating according to the present invention comprises: applying a planarizing coating composition according to the present invention onto a not-flat substrate; and curing the planarizing coating composition . The phrase "onto a substrate" as used for the manufacturing method means "on or above a substrate and below a photoresist layer" or "between a substrate and a photoresist layer". For example, a substrate-modifying layer may be formed over and in contact with a substrate, and a planarizing coating may be formed over and in contact with the substrate-modifying layer.

[0012]

A method for manufacturing a device according to the present invention comprises:

forming a planarizing coating according to the present invention ; applying a photoresist composition onto the planarizing coating, or forming an interlayer on the planarizing coating and applying a photoresist composition onto the interlayer;

curing the photoresist composition to form a photoresist layer;

exposing the substrate coated with the photoresist layer;

developing the exposed substrate to form a resist pattern ;

etching the planarizing coating or the interlayer through the resist pattern as a mask to pattern the coating or the interlayer; and

processing the substrate by etching it through the patterned planarizing coating or the patterned interlayer as a mask.

[Effects of I nvention]

[001 3]

A planarizing coating formed from the composition according to the present invention exhibits good coating formation property, is capable of gap filling of a processed substrate, and has high flatness. The

planarizing coating is produced from a monomer having a high carbon content and has high etching resistance. It has also been confirmed that the specific monomer used in the present invention is homogeneously soluble and stable in a specific solvent.

[Brief Description of Drawings]

[0014]

[Figure 1 ] Figure 1 is a schematic diagram illustrating a not-flat substrate. [Figure 2] Figure 2 is a schematic diagram illustrating how to form a coating of a composition on a not-flat substrate.

[Description of Embodiments]

[001 5]

The above summary and the following details are provided for illustration of the present invention, and are not intended to limit the claimed invention .

[001 6]

When a numerical range is specified herein using the numerical range includes both of the numbers indicated before and after "-" and the unit is the same for the two numbers, unless otherwise explicitly stated. For example, "5-25 mol%" means "5 mol% or more and 25 mol% or less".

[001 7]

The terms such as "C _x - _y ", " C _x -C _y ", and "C _x " as used herein represent the number of carbon atoms in a molecule or substituent. For example, "Ci-6 alkyl" refers to an alkyl chain having 1 -6 carbon atoms (such as methyl , ethyl , propyl , butyl , pentyl , and hexyl).

[001 8] When a polymer as described herein has plural types of repeating units, these repeating units are copolymerized . The copolymerization may be any one selected from alternating copolymerization, random

copolymerization , block copolymerization, graft copolymerization , and a combination thereof, unless otherwise explicitly stated .

[001 9]

The unit of temperatures as indicated herein is degree Celsius, unless otherwise explicitly stated . For example, "20 degrees" means "20 degrees Celsius" (20°C).

[0020]

Planarizing Coating-Forming Composition

The planarizing coating-forming composition according to the present invention is advantageously used in pattern formation by a lithography technique. The composition comprises: a monomer represented by formula (I ); and one or more organic solvents comprising a hydroxyl group and an ester-derivative group represented by formula (I I ) in a ratio of 23:77 to 77:23.

[0021 ]

The planarizing coating-forming composition according to the present invention is a composition that can be formed into a coating placed between a substrate and a photoresist coating and having an upper surface (the surface facing the photoresist) having high flatness. Preferably, an interlayer (such as a Si-containing resist interlayer, an adhesive layer, a bottom anti-reflective coating, or a combination thereof) may be formed on the upper surface of the planarizing coating (the surface facing the photoresist), and the photoresist layer may be formed on the interlayer. The substrate used in the present invention may be a flat substrate, in view of high etching resistance of the composition and the ease of handling. Even when the substrate is a not-flat substrate, the composition of the present invention exhibits its effect sufficiently by virtue of having good gap filling property.

[0022]

Monomer Represented by Formula (I)

The planarizing coating-forming composition comprises a monomer represented by formula (I).

[0023]

[Formula 3]

[0024]

An is a direct bond, C1-6 alkyi, Ce-12 cycloalkyi, or Ce-14 aryl. An is preferably a direct bond, C1-6 alkyi, or phenyl, more preferably a direct bond, linear C3 alkyi, linear C6 alkyi, tertiary butyl, or phenyl, and even more preferably a direct bond or phenyl.

[0025]

Ar2 is C1-6 alkyi, C6-12 cycloalkyi, or Ce-14 aryl. Ar2 is preferably isopropyl, tertiary butyl, C6 cycloalkyi, phenyl, naphthyl, phenanthryl, or biphenyl, and more preferably phenyl.

[0026]

Ri and R2 are each independently C1-6 alkyi, hydroxy, halogen, or cyano. Ri and R2 are preferably each independently methyl, ethyl, propyl, isopropyl, tertiary butyl , hydroxy, fluorine, chlorine, or cyano, and more preferably each independently methyl , hydroxy, fluorine, or chlorine.

[0027]

R3 is hydrogen , C1 -6 alkyl, or Ce-14 aryl. R3 is preferably hydrogen , C1 -6 alkyl, phenyl , more preferably hydrogen, methyl, ethyl, linear C5 alkyl, tertiary butyl, or phenyl , even more preferably hydrogen or phenyl , and still even more preferably hydrogen .

[0028]

When Ar2 is C1 -6 alkyl or Ce-14 aryl and R3 is C1 -6 alkyl or Ce-14 aryl , Ar2 and R3 are optionally linked to each other to form a hydrocarbon ring.

[0029]

r and s are each independently 0, 1 , 2, 3, 4, or 5. r and s are preferably each independently 0 or 1 . r and s are more preferably each independently 0.

[0030]

At least one of the Ci , C2, and C3 rings each surrounded by the broken line is an aromatic hydrocarbon ring fused with the adjacent aromatic hydrocarbon ring P i , and the total number of carbon atoms of the aromatic hydrocarbon ring and the aromatic hydrocarbon ring P i is preferably C10-14 and more preferably C10.

[0031 ]

At least one of the C4, C5, and C6 rings each surrounded by the broken line is an aromatic hydrocarbon ring fused with the adjacent aromatic hydrocarbon ring P2, and the total number of carbon atoms of the aromatic hydrocarbon ring and the aromatic hydrocarbon ring P2 is preferably C10-14 and more preferably C10.

[0032]

I n formula (I ), the bonding positions of Ri , R2 , and OH are not limited .

[0033] For example, the compound shown below can have the following structure of formula (I ). That is, the aromatic hydrocarbon ring Pi and the aromatic hydrocarbon ring C3 are fused with each other to form a naphthyl ring, and OH is bonded to the aromatic hydrocarbon ring C3. An is a direct bond , Ar2 and R3 are each phenyl, and A2 and R3 are linked to each other to form a hydrocarbon ring (fluorene).

[0034]

Formula 4]

[0035]

Specific examples of the monomer of formula (I ) are as follows.

[0036]

[Formula 5]

[0037]

[Formula 6]

[0038]

[Formula 7]

[0039]

In formulae (III), (IV), and (V), An, Ar2, Ri, R2, R3, r, and s are as defined above. Preferred examples of An, Ar2, Ri, R2, R3, r, and s are also each independently the same as described above. Among the monomers of formula (I), the monomer represented by formula (III) is more preferred.

[0040]

The monomer of formula (I) contained in the planarizing coating- forming composition is formed into a polymer by curing. The monomer is not limited to a single compound and may comprise a combination of a plurality of monomers as long as the monomers are those represented by formula (I). For example, the following two compounds may be contained as the monomer in the planarizing coating-forming composition.

[0041] Formula 8]

[0042]

When the combination of these monomers is employed, the monomers may be copolymerized or may each be polymerized alone. In terms of handling during manufacturing, it is preferable for the monomer of formula (I ) to consist of a single compound .

[0043]

Specific examples of the monomer of formula (I ) are shown below for illustrative purpose. These examples are not intended to limit the present invention .

[0044]

[Formula 9]

[0045]

The amount of the monomer of formula (I ) is preferably 5-30% by mass, more preferably 5-20% by mass, and even more preferably 8-1 5% by mass relative to the total amount of the planarizing coating-forming composition .

[0046]

Solid Component other than Monomer of Formula (I )

The planarizing coating-forming composition according to the present invention may further comprise a solid component that is other than the monomer of formula (I ) and that is formed into a coating. Such a solid component may be a monomer different from the monomer of formula (I ) or may be a polymer. When formed into a coating, the solid component may be copolymerized with , or polymerized separately from, the polymer of formula (I ), or both the copolymerization and separate polymerization may take place.

[0047]

One or More Organic Solvents Comprising Hydroxyl Group and Ester- Derivative Group Represented by Formula (I I ) in Ratio of 23:77 to 77:23

The planarizing coating-forming composition comprises one or more organic solvents comprising a hydroxyl group and an ester-derivative group represented by formula (I I ) in a molar ratio of 23:77 to 77:23.

[0048]

[Formula 10]

[0049]

R ₄ is a direct bond to a moiety of the organic solvent molecule other than the moiety of formula (I I ), a methyl, or carbon linked to R6 to form a saturated ring. R ₄ is preferably a direct bond to a moiety of the organic solvent molecule other than the moiety of formula (I I ) or a methyl .

[0050]

R5 is hydrogen or methoxy-substituted or unsubstituted C1-3 alkyl. R5 is preferably hydrogen or methoxy-substituted methyl.

[0051 ]

R6 is a methyl, or carbon linked to R ₄ to form a saturated ring. R6 is preferably a methyl .

[0052]

When the one or more organic solvents contained in the planarizing coating-forming composition consist of one kind of organic solvent, the hydroxyl group and the ester-derivative group represented by formula (I I) are present in one and the same molecule. When one molecule has one hydroxyl group and one ester-derivative group represented by formula (I I ), the molar ratio between the hydroxyl group and the ester-derivative group is 50:50. The number of carbon atoms in one molecule is preferably C3- 10 and more preferably C4-6.

[0053]

For example, ethyl lactate shown below is an organic solvent (C5) having a hydroxyl group and an ester-derivative group represented by formula (I I ) in one and the same molecule. R ₄ is a direct bond to a moiety other than the moiety of formula (I I ) (bond to a hydroxyl group via ethyl), R ₅ is hydrogen, and R6 is a methyl. The abundance ratio between the hydroxyl group and the ester-derivative group represented by formula (I I ) is 50:50 in molar ratio.

[0054]

[Formula 1 1 ]

[0055]

When the one or more organic solvents contained in the planarizing coating-forming composition consist of a plurality of (preferably two) organic solvents, it is preferable that the molecule containing a hydroxyl group and the molecule containing an ester-derivative group represented by formula (I I ) be different from each other. The number of carbon atoms in the molecule containing a hydroxyl group is preferably C 3-10 and more preferably C3-5. The number of carbon atoms in the molecule containing an ester-derivative group represented by formula (I I ) is preferably C3- 10 , more preferably C4-7 , and even more preferably C5-7.

[0056] For example, propylene glycol monomethyl ether (PGME) shown below is an organic solvent (C ₄ ) having a hydroxyl group.

[0057]

[Formula 12] Propylene glycol monomethyl ether [0058]

For example, γ-butyrolactone shown below is an organic solvent (C ₄ ) having an ester-derivative group represented by formula (I I ). R ₄ is carbon linked to R6 to form a saturated ring, R ₅ is hydrogen , and R6 is carbon linked to R ₄ to form a saturated ring.

[0059]

[Formula 13]

γ-Butyrolactone

[0060]

The one or more organic solvents of the planarizing coating-forming composition preferably comprise a hydroxyl group and an ester-derivative group represented by formula (I I ) in a molar ratio of 23:77 to 77:23. The present inventors have found that the presence of both the hydroxyl group and the ester-derivative group in the one or more organic solvents allows stable dissolution of the monomer of formula (I ) and leads to good coating formation property. The presence of the hydroxyl group in the one or more organic solvents is believed to contribute to the solubility of the hydroxyl group of the monomer of formula (I ), while the presence of the ester- derivative group in the one or more organic solvents is believed to contribute to the solubility of the aromatic ring of the monomer of formula (I ). The abundance ratio between the hydroxyl group and the ester- derivative group represented by formula (I I) in the one or more organic solvents is preferably 30:70 to 70:30 in molar ratio, more preferably 40:60 to 60:40 in molar ratio, even more preferably 45:55 to 55:45 in molar ratio, and still even more preferably 50:50 in molar ratio.

[0061 ]

The amount of the one or more organic solvents (or the total amount of a plurality of organic solvents) is preferably 60-95% by mass, more preferably 75-95% by mass, and even more preferably 82-92% by mass relative to the total amount of the planarizing coating-forming composition . The thickness of the coating to be formed can be controlled by increasing or reducing the amount of the one or more organic solvents relative to the total amount of the composition . The amount of water contained in the planarizing coating-forming composition is preferably 0.1 % by mass or less and more preferably 0.01 % by mass or less. Given the relationship with another layer or coating, it is preferable for the solvent to be free of water. I n an aspect of the present invention , the amount of water contained in the planarizing coating-forming composition is 0.00% by mass.

[0062]

For example, an organic solvent such as cyclohexanone may be capable of dissolving the monomer of formula (I ) to allow coating formation ; however, such an organic solvent has the problems of toxicity and irritation potential .

[0063]

When the one or more organic solvents contained in the planarizing coating-forming composition consist of one kind of organic solvent, the organic solvent is, for example, methyl lactate, ethyl lactate, n-butyl lactate, i-butyl lactate, sec-butyl lactate, n-amyl lactate, n-propyl lactate, i-propyl lactate, n-butyl lactate, i-butyl lactate, sec-butyl lactate, n-pentyl lactate, or sec-pentyl lactate. The organic solvent may be a mixture of these lactates. The organic solvent is preferably methyl lactate, ethyl lactate, or n-butyl lactate. The organic solvent is more preferably ethyl lactate. In an aspect of the present invention , the one or more organic solvents contained in the planarizing coating-forming composition consist only of any one selected from methyl lactate, ethyl lactate, and n-butyl lactate. In a more preferred aspect of the present invention, the one or more organic solvents consist only of ethyl lactate.

[0064]

When the one or more organic solvents contained in the planarizing coating-forming composition consist of a plurality of organic solvents, the organic solvent comprising a hydroxyl group is, for example, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, ethanol, n- propanol , i-propanol , n-butanol , i-butanol , sec-butanol , t-butanol , n- pentanol , i-pentanol, 2-methylbutanol, sec-pentanol , t-pentanol, 3- methoxybutanol , n-hexanol, 2-methylpentanol, sec-hexanol , 2-ethylbutanol , sec-heptanol , heptanol-3, n-octanol , 2-ethylhexanol , sec-octanol , n-nonyl alcohol, 2,6-dimethylheptanol-4, n-decanol , sec-undecyl alcohol ,

trimethylnonyl alcohol, sec-tetradecyl alcohol , sec-heptadecyl alcohol , phenol, cyclohexanol, methylcyclohexanol, 3,3,5-trimethylcyclohexanol , benzyl alcohol, phenylmethylcarbinol, diacetone alcohol, cresol, ethylene glycol , propylene glycol, 1 ,3-butylene glycol, pentanediol-2,4, 2- methylpentanediol-2,4, hexanediol-2,5, heptanediol-2,4, 2-ethylhexanediol- 1 ,3, diethylene glycol , dipropylene glycol , triethylene glycol , tripropylene glycol , glycerin , or a mixture thereof. The organic solvent is preferably propylene glycol monomethyl ether, propylene glycol monoethyl ether, ethanol , n-propanol , i-propanol, or a mixture thereof. The organic solvent is more preferably propylene glycol monomethyl ether or i-propanol and even more preferably propylene glycol monomethyl ether.

[0065]

When the one or more organic solvents contained in the planarizing coating-forming composition consist of a plurality of organic solvents, the organic solvent comprising an ester-derivative group represented by formula (I I ) is, for example, propylene glycol 1 -monomethyl ether 2-acetate (PGMEA), γ-butyrolactone, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, methyl acetate, γ-valerolactone, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, sec-butyl acetate, n-pentyl acetate, sec-pentyl acetate, 3-methoxybutyl acetate, methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, benzyl acetate, cyclohexyl acetate, methylcyclohexyl acetate, n-nonyl acetate, methyl acetoacetate, ethyl acetoacetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol mono-n-butyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, glycol diacetate, methoxytriglycol acetate, ethyl propionate, n-butyl propionate, i-amyl propionate, diethyl oxalate, di-n-butyl oxalate, diethyl malonate, dimethyl phthalate, diethyl phthalate, or a mixture thereof. The organic solvent is preferably propylene glycol 1 -monomethyl ether 2- acetate or γ-butyrolactone and more preferably propylene glycol 1 - monomethyl ether 2-acetate.

[0066]

I n a preferred aspect of the present invention , the one or more organic solvents contained in the planarizing coating-forming composition consist of two organic solvents, one of which is the organic solvent comprising a hydroxyl group and the other of which is the organic solvent comprising an ester-derivative group represented by formula (I I ).

[0067]

Surfactant

The planarizing coating-forming composition may further comprise a surfactant, a crosslinking agent, an acid generator, a radical generator, an agent for enhancing the adhesion to substrates, or a mixture thereof.

[0068]

A surfactant is useful for preventing the occurrence of pinholes, striation or the like and improving the ease of application and solubility of the planarizing coating-forming composition . The amount of the surfactant in the composition is preferably 0.01 -5% by mass and more preferably 0.05- 3% by mass relative to the total amount of the composition .

[0069]

Examples of the surfactant include: polyoxyethylene alkyl ether compounds such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, and polyoxyethylene oleyl ether; polyoxyethylene alkylaryl ether compounds such as polyoxyethylene octylphenol ether and polyoxyethylene nonylphenol ether; polyoxyethylene-polyoxypropylene block copolymer compounds; sorbitan fatty acid ester compounds such as sorbitan

monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan trioleate, and sorbitan tristearate; and polyoxyethylene sorbitan fatty acid ester compounds such as polyoxyethylene sorbitan monolaurate,

polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, and polyoxyethylene sorbitan tristearate. Other examples of the surfactant include: fluorosurfactants such as EFTOP (trade name) EF301 , EF303, and EF352 (manufactured by Tohkem Products

Corporation), MEGAFACE (trade name) F1 71 , F1 73, R-08, R-30, and R- 201 1 (manufactured by DI C Corporation), Fluorad FC430 and FC431 (manufactured by Sumitomo 3M Limited), AsahiGuard (trade name) AG71 0 (manufactured by Asahi Glass Co. , Ltd .), and SU RFLON S-382, SC1 01 , SC1 02, SC 103, SC1 04, SC1 05, and SC1 06 (manufactured by Asahi Glass Co. , Ltd .); and organosiloxane polymers such as KP341 (manufactured by Shin-Etsu Chemical Co. , Ltd.).

[0070]

Crosslinking Agent

A crosslinking agent can be added for the purpose of improving the coating formation property of the planarizing coating to be formed , preventing intermixing with an upper layer (such as a silicon-containing interlayer and a resist), and preventing diffusion of a low-molecular-weight component into the upper layer.

[0071 ]

Specific examples of crosslinking agents that can be used in the present invention include: melamine, guanamine, glycol uril , and urea compounds substituted by at least one group selected from a methylol group, an alkoxymethyl group, and an acyloxymethyl group; epoxy compounds; thioepoxy compounds; isocyanate compounds; azide compounds; and compounds having a double bond-containing group such as an alkenyl ether group. These may be used as an additive or may alternatively be introduced as a pendant group into a polymer side chain. Compounds containing a hydroxy group can also be used as a crosslinking agent.

[0072]

Examples of the epoxy compounds mentioned above include tris(2,3- epoxypropyl) isocyanurate, trimethylolmethane triglycidyl ether,

trimethylolpropane triglycidyl ether, and triethylolethane triglycidyl ether. Specific examples of the melamine compounds include hexamethylolmelamine, hexamethoxymethylmelamine, compounds derived by methoxymethylation of 1 -6 methylol groups of hexamethylolmelamine, mixtures of such compounds, hexamethoxyethylmelamine,

hexaacyloxymethylmelamine, compounds derived by acyloxymethylation of 1 -6 methylol groups of hexamethylolmelamine, and mixtures of such compounds. Examples of the guanamine compounds include

tetramethylolguanamine, tetramethoxymethylguanamine, compounds derived by methoxymethylation of 1 -4 methylol groups of

tetramethylolguanamine, mixtures of such compounds,

tetramethoxyethylguanamine, tetraacyloxyguanamine, compounds derived by acyloxymethylation of 1 -4 methylol groups of tetramethylolguanamine, and mixtures of such compounds. Examples of the glycoluril compounds include tetramethylolglycoluril, tetramethoxyglycoluril,

tetramethoxymethylglycoluril , compounds derived by methoxymethylation of 1 -4 methylol groups of tetramethylolglycoluril , mixtures of such compounds, compounds derived by acyloxymethylation of 1 -4 methylol groups of tetramethylolglycoluril , and mixtures of such compounds. Examples of the urea compounds include tetramethylolurea, tetramethoxymethylurea, compounds derived by methoxymethylation of 1 -4 of methylol groups of tetramethylolurea, mixtures of such compounds, and tetramethoxyethylurea.

[0073]

Examples of the compounds containing an alkenyl ether group include ethylene glycol divinyl ether, triethylene glycol divinyl ether, 1 ,2- propanediol divinyl ether, 1 ,4-butanediol divinyl ether, tetramethylene glycol divinyl ether, neopentyl glycol divinyl ether, trimethylolpropane trivinyl ether, hexanediol divinyl ether, 1 ,4-cyclohexanediol divinyl ether,

pentaerythritol trivinyl ether, pentaerythritol tetravinyl ether, sorbitol tetravinyl ether, sorbitol pentavinyl ether, and trimethylolpropane trivinyl ether. [0074]

Examples of the crosslinking agent used in the present invention include those represented by formula (VI).

[0075]

[Formula 14]

[0076]

In formula (VI), l_3 is a direct bond or substituted or unsubstituted C1-3 alkyl. L3 is preferably a direct bond or methyl and more preferably a direct bond. The substituent of C1-3 alkyl is preferably hydrogen, methyl, Ce-ιο aryl, or a substituent represented by formula (VII) or formula (VIII) and more preferably methyl or a substituent represented by formula (VII). In formula (VI), R11 is hydrogen or methyl.

[0077]

(V I I

[0078]

[Formula 16] Specific examples of the crosslinking agent represented by formula (VI ) include the following compounds, to which the scope of the present invention is not limited .

[0080]

[0081 ]

The amount of the crosslinking agent in the present invention is preferably 3-50% by mass and more preferably 5-40% by mass relative to the mass of the monomer of formula (I ) contained in the planarizing coating- forming composition .

[0082]

The monomer of formula (I ) is self-crosslinkable, which allows a reduction in the amount of the crosslinking agent to be added to the planarizing coating-forming composition . Whether to reduce the amount of the crosslinking agent can be selected depending on the apparatus and conditions employed for the process. When the amount of the crosslinking agent is reduced , the concentration of the crosslinking agent is preferably 0-1 ,000 ppm and more preferably 0-500 ppm in the planarizing coating- forming composition . Given the ease of process control, the present invention may be implemented as an embodiment in which the crosslinking of the composition into a coating is allowed to proceed only by self- crosslinking of the monomer of formula (I ) without addition of any

crosslinking agent (this means that the amount of the crosslinking agent may be 0 ppm in the planarizing coating-forming composition).

[0083] Acid Generator

The planarizing coating-forming composition according to the present invention may further comprise an acid generator. The amount of the acid generator contained in the composition is preferably 0.1 -1 0% by mass and more preferably 1 -7% by mass relative to the mass of the monomer of formula (I).

[0084]

The acid generator can be a thermal acid generator capable of generating a strong acid when heated . The thermal acid generator (TAG) used in the present invention can comprise one or more thermal acid generators which , when heated, generate an acid capable of reacting with the monomer of formula (I ) present in the present invention and capable of promoting crosslinking of the monomer. The acid is more preferably a strong acid such as sulfonic acid . The thermal acid generator is preferably activated at a temperature above 80 degrees. Examples of the thermal acid generator include: metal-free sulfonium salts such as triarylsulfonium , dialkylarylsulfonium , and diarylalkylsulfonium salts of strong non- nucleophilic acids; metal-free iodonium salts such as alkylaryliodonium and diaryliodonium salts of strong non-nucleophilic acids; and ammonium , alkylammonium , dialkylammonium , trialkylammonium, and

tetraalkylammonium salts of strong non-nucleophilic acids. Covalent thermal acid generators are also considered useful as additives, and examples include 2-nitrobenzyl esters of alkylsulfonic or arylsulfonic acids and other sulfonic acid esters which are thermally decomposed to give free sulfonic acid . Examples thereof include diaryliodonium perfluoroalkyl sulfonates, diaryliodonium tris(fluoroalkylsulfonyl)methides, diaryliodonium bis(fluoroalkylsulfonyl)methides, diaryliodonium

bis(fluoroalkylsulfonyl)imides, and diaryliodonium quaternary ammonium perfluoroalkyl sulfonates. Examples of labile esters include: nitrobenzyl tosylates such as 2-nitrobenzyl tosylate, 2,4-dinitrobenzyl tosylate, 2,6- dinitrobenzyl tosylate, and 4-nitrobenzyl tosylate; benzenesulfonates such as 2-trifluoromethyl-6-nitrobenzyl 4-chlorobenzenesulfonate and 2- trifluoromethyl-6-nitrobenzyl 4-nitrobenzenesulfonate; phenolic sulfonate esters such as phenyl 4-methoxybenzenesulfonate; quaternary ammonium tris(fluoroalkylsulfonyl)methides; quaternary alkylammonium

bis(fluoroalkylsulfonyl)imides; and alkylammonium salts of organic acids such as triethylammonium salt of 1 0-camphorsulfonic acid . A variety of amine salts of aromatic (anthracene, naphthalene, or benzene derivative) sulfonic acids, including those disclosed in U .S. Patent Nos. 3,474,054 (Patent Literature 2), 4,200,729 (Patent Literature 3), 4,251 ,665 (Patent Literature 4), and 5, 187,019 (Patent Literature 5), can be used as the TAG.

[0085]

Specific examples of the acid generator that can be contained in the planarizing coating-forming composition include the following compounds, to which the scope of the present invention is not limited.

[0086]

[Formula 18] Triethylamine [0087]

The monomer of formula (I ) is self-crosslinkable, which allows a reduction in the amount of the acid generator to be added to the planarizing coating-forming composition . Whether to reduce the amount of the acid generator can be selected depending on the apparatus and conditions employed for the process. When the amount of the acid generator is reduced, the concentration of the acid generator is preferably 0-500 ppm in the planarizing coating-forming composition . Given the ease of process control, the present invention may be implemented as an embodiment in which no acid generator is added to the planarizing coating-forming composition (this means that the amount of the acid generator may be 0 ppm in the planarizing coating-forming composition).

[0088]

Other Components

To the planarizing coating-forming composition according to the present invention there may be further added other components such as a radical generator, an agent for enhancing the adhesion to substrates, a lubricating agent, a monomeric dye, a lower alcohol ( C 1 -6 alcohol), a surface leveling agent, an anti-foaming agent, and a preservative agent. The amount of these components in the composition is preferably 0.1 -1 0% by mass and more preferably 0.5-5% by mass relative to the amount of the monomer of formula (I ) in the composition . I n an aspect of the present invention , the composition contains none of these components (0% by mass).

[0089]

Method for Manufacturing Planarizing Coating

An aspect of the method for forming a planarizing coating according to the present invention will be described .

[0090]

As previously described , a "planarizing coating-forming composition" as defined in the present invention refers to a composition that can be formed into a coating placed between a substrate and a photoresist coating and having an upper surface (the surface facing the photoresist) having high flatness. Having high flatness means that the upper surface of the planarizing coating formed is horizontal . When the planarizing coating has high flatness, the variation in distance between the horizontally positioned bottom surface of a substrate (or the lowest substrate of a plurality of stacked substrates) and the upper surface of the coating is small. A "flat substrate" refers to a substrate in which the distance between the bottom surface and top surface is substantially constant (the variation in the distance is from 0-3% in the substrate). A "not-flat substrate" broadly refers to a substrate that is not a flat substrate.

[0091 ]

Hereinafter, the present invention will be described with reference to the drawings for ease of understanding. To obtain a composition capable of being suitably formed into a coating on a substrate having a dense region and sparse region, the present inventors examined Examples and

Comparative Examples using a substrate shown in Figure 1 . An inexact reduction scale is used in Figures 1 and 2 for ease of understanding of the invention . Reference numeral 1 denotes an island region , which extends over 1 00 μηη or more. Reference numeral 2 denotes a sea region , which has 1 00 μηη width . Reference numeral 3 denotes a dense region , which extends over 1 00 μηη or more and in which wall structures with a depth of 1 00 nm are arranged in parallel, with a half pitch of 0.04 μηη and a line-to- space ratio of 1 :2.5. The substrate is a S1 O2 wafer having a sufficient width . Reference numeral 4 denotes the bottom surface of the substrate, and reference numeral 5 denotes the lower part of the substrate. When the substrate has a plurality of sea regions or gaps, a height or distance as described in the present invention is determined on the basis of one of the sea regions or gaps that is nearest the bottom surface (with the exception of a hole piercing through the substrate and a structure deviating from the intended design). Reference numeral 6 denotes the top part of the substrate. When the substrate has a plurality of top parts or gaps, a height or distance as described in the present invention is determined on the basis of one of the top parts that is farthest from the bottom surface (with the exception of a structure deviating from the intended design). Reference numeral 7 denotes a height between the island region and the sea region and corresponds to the difference between the distance from the top part of the island region to the bottom surface and the distance from the lower part contiguous with the island region to the bottom surface. Reference numeral 8 denotes a height between the dense region and the sea region and corresponds to the difference between the distance from the top part of the dense region to the bottom surface and the distance from the lower part contiguous with the dense region to the bottom surface. A planarizing coating is formed as shown by reference numeral 9 in Figure 2; it is difficult for the coating to be completely flat (being "completely flat" means that the distance from the coating to the bottom surface is constant). Reference numeral 1 0 denotes the height from the bottom surface of the substrate to the upper surface of the planarizing coating formed on the island region , while reference numeral 1 1 denotes the height from the bottom surface of the substrate to the upper surface of the planarizing coating formed on the dense region . The planarizing coating-forming composition discovered by the present inventors is advantageous because it can be formed into a coating on a not-flat substrate so that the difference between the heights denoted by reference numeral 1 0 and reference numeral 1 1 becomes small (so that high flatness is achieved). In evaluation of this composition , the difference between the heights is referred to as a "flatness index".

[0092]

Examples of the not-flat substrate in the present invention include a silicon-containing substrate with a difference in height between the top part and the lower part (namely a difference between the distance from the top part to the bottom surface and the distance from the lower part to the bottom surface) of 20-1 0,000 nm . The difference in height is preferably 50-1 ,000 nm and more preferably 50-500 nm. It is preferable to determine the difference in height in a structure where the top part and the lower part adjoin to each other as shown by reference numerals 7 and 8. Other examples of the not-flat substrate include a substrate having a wall or contact hole resulting from pre-treatment and further include a substrate in which the difference between the distance from the top part to the bottom surface and the distance from the lower part to the bottom surface is 30- 95% (preferably 30-80%) of the values mentioned above. The wall or contact hole can be formed by a known technique such as lithography, etching, or DSA, and preferably has an aspect ratio of 3-25 (preferably 5- 1 0). A substrate in which wall structures are merely arranged at intervals (see the region denoted by reference numeral 3 in Figure 1 ) is also a not- flat substrate. The advantage of the planarizing coating-forming

composition becomes evident, for example, when the substrate has both a region where such structures are densely arranged (dense region) and a region where such structures are absent (sparse region). Furthermore, the planarizing coating-forming composition according to the present invention is applicable to a substrate with a step (see the regions denoted by reference numeral 1 and reference numeral 2 in Figure 1 ). The height of the step is preferably 20-1 0,000 nm, more preferably 50-1 ,000 nm , and even more preferably 50-500 nm.

[0093]

When the planarizing coating-forming composition according to the present invention is applied to a flat substrate (bare wafer) and formed into a planarizing coating by heating, the planarizing coating can have a thickness of 20-2, 000 nm (preferably 1 00-500 nm , more preferably 200-400 nm).

[0094]

As described above, the substrate used can be a flat substrate or a not-flat substrate. The advantage of the present invention becomes more evident when a not-flat substrate is used . [0095]

The substrate used can be a metal-containing substrate or a silicon- containing substrate. The substrate used in the present invention may be a single-layer substrate or a multi-layer substrate composed of a plurality of substrate layers. As the substrate there can be used any known substrate such as a silicon-coated substrate, silicon dioxide-coated substrate, silicon nitride-coated substrate, silicon wafer substrate (such as a S 1 O2 wafer), glass substrate, indium-containing substrate (such as an ITO substrate), or titanium-containing substrate (such as a titanium nitride or titanium oxide substrate).

[0096]

I n the process for manufacturing a semiconductor according to the present invention, any known manner can be employed for the configuration of the substrate according to the conditions of the process. Examples of the configuration of the substrate include the multi-layer configurations listed below. The left-to-right direction in the following list corresponds to the bottom-to-top direction in the multi-layer configurations.

[0097]

Silicon wafer substrate

Silicon wafer substrate/titanium-containing substrate

Silicon wafer substrate/titanium-containing substrate/silicon-coated substrate

Silicon wafer substrate/titanium-containing substrate/silicon dioxide- coated substrate

Silicon wafer substrate/silicon dioxide-coated substrate/titanium- containing substrate

Silicon nitride substrate

Silicon nitride substrate/titanium-containing substrate Silicon nitride substrate/titanium-containing substrate/silicon-coated substrate

Silicon nitride substrate/titanium-containing substrate/silicon dioxide- coated substrate

Silicon nitride substrate/silicon dioxide-coated substrate/titanium- containing substrate

[0098]

One substrate to be laminated on another substrate can be formed by a known technique such as CVD. The one substrate can be patterned by a known lithography technique or etching technique. Still another substrate can be laminated on the patterned substrate by a known technique such as CVD.

[0099]

I n the present invention , the planarizing coating-forming composition according to the present invention is applied by an appropriate application means such as a spinner or coater. The planarizing coating-forming composition is good at gap filling of the substrate, since the solid

component of the planarizing coating-forming composition is the monomer of formula (I ) at the moment when the composition is applied. In the application of the planarizing coating-forming composition to the substrate, it is preferable for the substrate and the planarizing coating-forming composition to come into direct contact with each other, but the planarizing coating-forming composition may be applied with another thin coating (such as a substrate-modifying layer) interposed between the composition and the substrate. The applied composition is then heated to form a planarizing coating. As for the heating conditions, the heating temperature is typically selected from the range of 200-400°C (preferably 225-375°C, more preferably 250-350°C), and the heating time is typically selected from the range of 30-1 80 seconds (preferably 30-120 seconds). The heating allows polymerization of the monomer of formula (I ) in the applied composition to proceed , thereby forming a planarizing coating. The heating can be carried out in separate steps (step bake). For example, the heating may be two-step heating consisting of: first heating by which the substrate is gap-filled along with removal of the solvent; and second heating by which the composition is mildly reflowed and thus formed into a coating with high flatness. For example, it is preferable that the first heating be performed at 200-300°C for 30-120 seconds and the second heating be performed at 300-400°C for 30-120 seconds. The heating may be performed in an air atmosphere, whose oxygen concentration can be reduced to prevent oxidation of the planarizing coating composition and planarizing coating. For example, the oxygen concentration may be adjusted to 1 ,000 ppm or less (preferably 100 ppm or less) by introducing an inert gas ( N2, Ar, He, or a mixture thereof) into the atmosphere.

[01 00]

The planarizing coating comprises a coating resulting from

polymerization of the monomer of formula (I ); thus, the planarizing coating has a high carbon content and can be etched at a low etching rate. The planarizing coating is therefore suitable for being formed by a spin-on- coating method . The evaluation of the etching rate can be made by a known technique. For example, the ratio of the etching rate of the coating to that of a resist (UV 1 610, manufactured by Dow Chemical Company) is preferably 1 .0 or less, more preferably 0.9 or less, and even more preferably 0.8 or less.

[01 01 ]

Formation of Photoresist Coating and Other Coatings

A photoresist composition (such as a positive-type photoresist composition) is applied to the planarizing coating formed as described above. The positive-type photoresist composition as described herein refers to a photoresist composition that undergoes a reaction under light irradiation and whose light-irradiated portion has an increased solubility in a developer. The photoresist composition used is not particularly limited, and any positive-type photoresist composition , negative-type photoresist composition , or negative tone development (NTD) photoresist composition can be used , as long as the photoresist composition is sensitive to the exposure light for pattern formation .

[01 02]

I n the method for manufacturing a resist pattern according to the present invention , a coating or layer other than the planarizing coating formed from the planarizing coating-forming composition and the

photoresist coating may be present. An interlayer may be interposed between the planarizing coating and the photoresist coating so that the planarizing coating and the photoresist coating are not in direct contact with each other. The interlayer is a coating formed between the photoresist coating and the planarizing coating, and examples of the interlayer include a bottom anti-reflecting coating (BARC layer), an inorganic hard mask interlayer (such as a silicon oxide coating, silicon nitride coating, or silicon oxynitride coating), and an adhesive coating. The inorganic hard mask interlayer can be formed by reference to Japanese Patent No. 5336306 B2 (Patent Literature 6). The interlayer may consist of a single layer or a plurality of layers. A top anti-reflective coating (TARC layer) may be formed on the photoresist coating.

[01 03]

I n the process for manufacturing a semiconductor according to the present invention, any known manner can be employed for the configuration of the layers other than the planarizing coating according to the conditions of the process. Examples include the following multi-layer configurations.

[01 04] Substrate/planarizing coating/photoresist coating

Substrate/planarizing coating/BARC layer/photoresist coating

Substrate/planarizing coating/BARC layer/photoresist coating/TARC layer

Substrate/planarizing coating/inorganic hard mask

interlayer/photoresist coating/TARC layer

Substrate/planarizing coating/inorganic hard mask interlayer/BARC layer/photoresist coating/TARC layer

Substrate/planarizing coating/adhesive coating/BARC

layer/photoresist coating/TARC layer

Substrate/substrate-modifying layer/planarizing coating/BARC layer/photoresist coating/TARC layer

Substrate/substrate-modifying layer/planarizing coating/adhesive coating/BARC layer/photoresist coating/TARC layer

[01 05]

These layers can be cured by heating and/or exposure after being applied or can be formed by a known technique such as CVD. These layers can be removed by a known technique (such as etching) and can each be patterned through an upper layer as a mask.

[01 06]

I n an aspect of the present invention , the planarizing coating can be formed on a not-flat substrate, and another substrate can be formed on the planarizing coating. The other substrate can be formed , for example, by a technique such as CVD. The lower substrate and the upper substrate may have the same composition or different compositions. Still another layer can further be formed on the upper substrate. Forming the planarizing coating or a photoresist coating as the other layer enables processing of the upper substrate. A photoresist coating or another coating that can be employed is as described above. [01 07]

Patterning and Device Manufacturing

The photoresist coating is exposed through a given mask. The wavelength of the light used for exposure is not particularly limited. The exposure is preferably performed with light having a wavelength of 1 3.5-248 nm. Specifically, KrF excimer laser (wavelength : 248 nm), ArF excimer laser (wavelength : 1 93 nm), or extreme ultraviolet light (wavelength : 1 3.5 nm) can be used, and KrF excimer laser is more preferred . These wavelengths may vary within ±1 %. The exposure can , if desired , be followed by post-exposure bake. The temperature for the post-exposure bake is selected from the range of 80-1 50°C, preferably 1 00-140°C, and the heating time for the post-exposure bake is selected from the range of 0.3-5 minutes, preferably 0.5-2 minutes.

[01 08]

Next, development is performed with a developer. When a positive- type photoresist composition is used , the exposed part of the positive-type photoresist layer is removed by the development, resulting in the formation of a photoresist pattern . This photoresist pattern can be made finer using, for example, a shrink material .

[01 09]

A 2.38% by mass aqueous TMAH solution is preferred as the developer used for the development in the above photoresist pattern formation method . The use of such a developer allows easy dissolution and removal of the planarizing coating at room temperature. An additive such as a surfactant can be added to the developer. The temperature of the developer is typically selected from the range of 5-50°C, preferably 25- 40°C, and the development time is typically selected from the range of 1 0- 300 seconds, preferably 30-60 seconds.

[01 1 0] The interlayer can be patterned through the resulting photoresist pattern as a mask. For pattern formation , a known technique such as etching (dry etching or wet etching) can be used . For example, the interlayer may be etched through the photoresist pattern as an etching mask, and then the planarizing coating and substrate may be etched through the resulting interlayer pattern as an etching mask to form a pattern on the substrate. Alternatively, the inorganic hard mask interlayer may be etched through the photoresist pattern as an etching mask, the planarizing coating may be etched through the resulting inorganic hard mask interlayer pattern as an etching mask, and then the substrate may be etched through the resulting planarizing coating pattern as an etching mask to form a pattern on the substrate. Wiring can be formed in the substrate using the pattern formed on the substrate.

[01 1 1 ]

For example, the planarizing coating can be suitably removed by dry etching with O2, CF ₄ , C H F3, C , or BCI3. O2 or CF ₄ can be suitably used .

[01 12]

Subsequently, the substrate, if necessary, is further processed to form a device. Such further processing can be done by using a known method . After formation of the device, the substrate, if necessary, is cut into chips, which are connected to a leadframe and packaged with a resin .

I n the present invention, the packaged product is referred to as a device.

Preferred examples of the device include a semiconductor, a solar cell , an organic EL element, and an inorganic EL element. A semiconductor is more preferred .

[01 1 3]

Examples Hereinafter, the present invention will be described with specific examples. These examples are given only for illustrative purpose and not intended to limit the scope of the present invention.

[0114]

Preparation Example 1 of Composition 1

Compound 1 shown below (manufactured by Mitsubishi Gas Chemical Company, Inc.) is dissolved in ethyl lactate (manufactured by KANTO

CHEMICAL CO., INC., abbreviated as EL) to a concentration of 10% by mass. The resulting solution was used as composition 1.

[0115]

Compound 1

[0116]

Example 1-1: Evaluation of Solubility and Stability for Composition 1

The extent of dissolution of the solute in composition 1 was visually observed and evaluated as follows.

[0117]

A: The solute was fully dissolved.

B: The solute remained not fully dissolved.

[0118]

When the solubility was rated as "A", the composition was stored at 0°C for 1 month, and the storage behavior was visually observed and evaluated as follows.

[0119]

A: No precipitate was formed. B: A precipitate was formed .

[0120]

Example 1 -2: Evaluation of Coating Formation Property of Composition 1

Composition 1 was applied to a bare silicon wafer using a spin coater (MS-1 50A, manufactured by Mikasa Co. , Ltd .) at 1 ,500 rpm , baked at 250°C for 1 minute, and further baked at 350°C for 1 minute to obtain a planarizing coating. It was confirmed by a spectroscopic reflectometer (Lambda Ace VM-31 10, manufactured by Dainippon Screen Mfg. , Co. , Ltd .) that this planarizing coating had a thickness of 300 nm .

[0121 ]

The surface of the planarizing coating was observed with an optical microscope, and the coating formation property was evaluated as follows.

[0122]

A: A uniform coating formed in which any marking resulting from uneven distribution of the composition was not found .

B: A marking such as striation (radial patch or stripe) was found .

[0123]

Example 1 -3: Evaluation of Filling Property of Composition 1

Composition 1 was applied to a S 1 O2 wafer (not-flat substrate) shown in Figure 1 using a spin coater (MS-1 50A, manufactured by Mikasa Co. , Ltd .) at 1 ,500 rpm so that the composition filled the sea regions and the gaps between the walls in the dense regions and covered the island regions. The composition was baked at 250°C for 1 minute and further baked at 350°C for 1 minute to obtain a planarizing coating. A section of the planarizing coating was prepared , and gaps between walls in a dense region of the section of the coating were observed in a photograph taken by a SEM (S-5500, manufactured by Hitachi High-tech Fielding Corporation), and the filling property of composition 1 was evaluated as follows.

[0124] A: The composition successfully filled the gaps so that no gap with voids or pores was found .

B: The composition failed to sufficiently fill the gaps so that a gap with voids or pores was present.

[0125]

Example 1 -4: Evaluation of Flatness for Composition 1

To evaluate the degree of flatness achieved by composition 1 , the flatness index (the difference between the heights denoted by reference numeral 1 0 and reference numeral 1 1 in Figure 2) was measured in the SEM photograph taken in Example 1 -3 described above. The flatness index of the planarizing coating formed from composition 1 was 10 nm.

[0126]

Preparation Example 2 of Composition 2

Composition 2 was prepared by the same procedure as in

Preparation Example 1 , except that a solvent was prepared by mixing

PGME and PGM EA in a molar ratio of 59 : 41 (this solvent is referred to as "PGME: PG MEA = 59:41 " (weight ratio of 1 : 1 )) and was substituted for EL used in Preparation Example 1 .

[0127]

Preparation Example 3 of Composition 3

Composition 3 was prepared by the same procedure as in

Preparation Example 1 , except that a solvent was prepared by mixing PGM E and PGMEA in a molar ratio of 77: 23 (this solvent is referred to as "PGM E: PGM EA = 77:23") and was substituted for EL used in Preparation Example 1 .

[0128]

Preparation Example 4 of Composition 4

Composition 4 was prepared by the same procedure as in

Preparation Example 1 , except that a solvent was prepared by mixing PGME and PGM EA in a molar ratio of 39:61 (this solvent is referred to as "PGM E: PGM EA = 39:61 ") and was substituted for EL used in Preparation Example 1 .

[0129]

Preparation Example 5 of Composition 5

Composition 5 was prepared by the same procedure as in

Preparation Example 1 , except that a solvent was prepared by mixing PGME and PGM EA in a molar ratio of 50:50 (this solvent is referred to as "PGM E: PGM EA = 50:50") and was substituted for EL used in Preparation Example 1 .

[01 30]

Evaluation of Examples 2-1 0

Compositions 2-5 were subjected to the same evaluation procedures as in Example 1 (Examples 1 -1 to 1 -4). The baking conditions in Example 1 -3 were changed as shown in Table 1 , and the conditions for the other procedures were unchanged . The evaluation results are shown in Table 1 .

[01 31 ]

Comparative Preparation Example 1 of Comparative Composition 1 and Evaluation of Comparative Example 1

Comparative composition 1 was prepared by the same procedure as in Preparation Example 1 , except for substituting PGME for EL used in Preparation Example 1 . The solubility was evaluated in the same manner as in Example 1 -1 and was consequently rated as "B". The evaluation result is shown in Table 1 .

[01 32]

Comparative Preparation Example 2 of Comparative Composition 2 and Evaluation of Comparative Example 2

Comparative composition 2 was prepared by the same procedure as in Preparation Example 1 , except for substituting PGMEA for EL used in Preparation Example 1 . The solubility was evaluated in the same manner as in Example 1 -1 and was consequently rated as "B". The evaluation result is shown in Table 1 .

[01 33]

Comparative Preparation Example 3 of Comparative Composition 3 and Evaluation of Comparative Example 3

The following experiment was conducted to examine whether a composition disclosed as a bottom coating-forming material in Patent Literature 1 is suitable for use as the planarizing coating-forming

composition of the present application . An amount of 7.2 g of compound 1 shown above and 2.5 g of N I KALAC MX270 (manufactured by SANWA CH EMI CAL CO. , LTD.) were dissolved in 85.9 g of a cyclohexanone solvent to obtain comparative composition 3. It was confirmed by visual observation that both of the solutes were fully dissolved.

[01 34]

Comparative composition 3 was formed into a coating in the same manner as in Example 1 -3, except for changing the baking to step bake in which the composition was baked at 200°C for 1 minute and then 250°C for 1 minute. Evaluation of the flatness was made in the same manner as in Example 1 -4. As a result, the flatness index of the coating formed from comparative composition 3 was determined to be 55 nm .

[01 35]

[Table 1 ]

[Reference Signs List]

[01 36]

1 . Island region of substrate

2. Sea region of substrate

3. Dense region of substrate

4. Bottom surface of substrate

5. Lower part of substrate

6. Top part of substrate

7. Height between island region and sea region

8. Height between dense region and sea region

9. Formed planarizing coating 1 0. Height between top part of island region and bottom surface of substrate

1 1 . Height between top part of dense region and bottom surface of substrate