Composition for coating uneven substrates containing a compound having a curable functional group

Abstract

[Problem] To provide a composition for coating a substrate with level difference, said composition forming a coating film that is capable of filling and flattening a pattern. [Solution] A composition for coating a substrate with level difference, said composition containing a solvent and a compound (A) which serves as a base material, and which contains a partial structure that is represented by formula (A-1), formula (A-2) or formula (A-3). This composition for coating a substrate with level difference is cured by means of light irradiation or heating. In formula (A-1) and formula (A-2), the broken line represents a bond to an aromatic ring; the aromatic ring constitutes a polymer skeleton or a monomer; and n represents an integer of 1 or 2. In formula (A-3), the chain line represents a bond to a carbon chain, alicyclic carbon ring or aromatic ring that constitutes a polymer skeleton; Q represents a single bond or an organic group having an ether bond, an ester bond, a urethane bond, an alkylene bond having 1 to 3 carbon atoms or an amide bond; and m represents 1. Formula (A-3) does not include formula (A-1).

Description

[Technical Field]

[0001] The present invention relates to a coating composition for uneven substrates that is cured by light irradiation or heat to form a planarizing film on a substrate having steps, and to a method for producing a planarized laminated substrate using the coating composition for uneven substrates. [Background technology]

[0002] In recent years, semiconductor integrated circuit devices have been fabricated to finer design rules. In order to form finer resist patterns using photolithography technology, it is necessary to shorten the exposure wavelength.

[0003] However, as the exposure wavelength becomes shorter, the depth of focus decreases, making it necessary to improve the planarization of the coating formed on the substrate. In other words, substrate planarization technology is becoming increasingly important for manufacturing semiconductor devices with fine design rules.

[0004] As a method for forming a planarizing film, for example, a method for forming a resist underlayer film under a resist film by photo-curing has been disclosed.

[0005] A resist underlayer film-forming composition containing a polymer having an epoxy group or an oxetane group in the side chain and a photocationic polymerization initiator, or a resist underlayer film-forming composition containing a polymer having a radically polymerizable ethylenically unsaturated bond and a photoradical polymerization initiator has been disclosed (see Patent Document 1).

[0006] In addition, a resist underlayer film-forming composition has been disclosed that contains a silicon-based compound having a cationic polymerizable reactive group such as an epoxy group or a vinyl group, a photocationic polymerization initiator, and a photoradical polymerization initiator (see Patent Document 2).

[0007] Also disclosed is a method for manufacturing a semiconductor device using a resist underlayer film containing a polymer having a crosslinkable functional group (for example, a hydroxy group) in the side chain, a crosslinking agent, and a photoacid generator (see Patent Document 3).

[0008] Furthermore, although not a photocrosslinkable resist underlayer film, a resist underlayer film having an unsaturated bond in the main chain or side chain has been disclosed (see Patent Documents 4 and 5).

[0009] Also disclosed is a resist underlayer film made of a polymer having an epoxy group on the side chain (see Patent Document 6). [Prior art documents] [Patent documents]

[0010] [Patent Document 1] International publication pamphlet WO2006 / 115044 [Patent Document 2] International Publication Pamphlet WO2007 / 066597 [Patent Document 3] International publication pamphlet WO2008 / 047638 [Patent Document 4] International Publication Pamphlet WO2009 / 008446 [Patent Document 5] Special Publication 2004-533637 [Patent Document 6] International Publication Pamphlet WO2019 / 054420 Summary of the Invention [Problem to be solved by the invention]

[0011] In conventional photocrosslinking materials, for example, in resist underlayer film-forming compositions containing a polymer having a thermally crosslinkable functional group such as a hydroxyl group, a crosslinker, and an acid catalyst (acid generator), when the composition is heated to fill a pattern (e.g., a hole or trench structure) formed on a substrate, the crosslinking reaction proceeds, causing an increase in viscosity, resulting in poor filling of the pattern. Furthermore, thermal shrinkage due to degassing occurs, causing problems with loss of flatness.

[0012] Therefore, an object of the present invention is to provide a coating composition for coating a substrate with unevenness, which has high pattern filling properties, is capable of forming a coating film on a substrate, and has planarizing properties that do not cause outgassing or thermal shrinkage. [Means for solving the problem]

[0013] A first aspect of the present invention is a composition for covering an uneven substrate, comprising a compound (A) as a main component and a solvent, The compound (A) is represented by the following formula (A-1), formula (A-2) or formula (A-3): [ka] [ka] (In the formula, the dashed line indicates a bond to an aromatic ring, and the aromatic ring is an aromatic ring constituting the polymer skeleton or an aromatic ring constituting the monomer, and n is an integer of 1 to 4.) [ka] (wherein the chain line represents a bond to a linear carbon chain, alicyclic carbon ring or aromatic ring constituting the polymer skeleton; Q represents a single bond, or an organic group having an ether bond, ester bond, urethane bond, alkylene bond having 1 to 3 carbon atoms or amide bond; provided that formula (A-3) does not include formula (A-1); and m represents 1), a coating composition for substrates with uneven surfaces which is cured by irradiation with light or heat; As a second aspect, the composition for covering a stepped substrate according to the first aspect, wherein the aromatic ring is a benzene ring, a naphthalene ring, or an anthracene ring; According to a third aspect, the present invention provides the composition for covering stepped substrates according to the first or second aspect, wherein the polymer containing an aromatic ring is a polymer containing a hydroxyaryl novolak structure, and the hydroxyl group thereof is substituted with a partial structure of formula (A-1) or formula (A-2). As a fourth aspect, the composition for covering a stepped substrate according to the first aspect or the second aspect, wherein the aromatic ring-containing monomer is a monomer in which a hydroxyl group of the aromatic ring is substituted with a partial structure of formula (A-1) or formula (A-2). According to a fifth aspect, the composition for covering a substrate with irregularities according to any one of the first to fourth aspects further contains an acid generator. According to a sixth aspect, the composition for covering a substrate with irregularities according to any one of the first to fifth aspects further contains a surfactant. As a seventh aspect, a method for producing a coated substrate, the method comprising: step (i) of applying the stepped substrate coating composition according to any one of the first to sixth aspects to a substrate having a step; and step (ii) of exposing the composition applied in step (i) to light or heating it during or after exposure. As an eighth aspect, the method for producing a coated substrate according to the seventh aspect, further comprising the step (ia) of heating the stepped substrate coating composition on the substrate having steps at a temperature of 70°C to 400°C for 10 seconds to 5 minutes before the exposing step (ii). As a ninth aspect, the method for producing a coated substrate according to the seventh or eighth aspect, wherein in step (ii), the light used for exposure has a wavelength of 150 nm to 700 nm; According to a tenth aspect, in the step (ii), the exposure light amount is 10 mJ / cm 2 ~5000mJ / cm 2 The method for producing a coated substrate according to any one of the seventh to ninth aspects, As an eleventh aspect, the method for producing a coated substrate according to the seventh aspect, wherein in step (ii), heating is performed at a temperature of 100°C to 500°C; As a twelfth aspect, the method for producing a coated substrate according to any one of the seventh to eleventh aspects, in which the substrate having a step has an open area (non-pattern area) and a pattern area consisting of DENCE (dense) and ISO (coarse), and the aspect ratio of the pattern is 0.1 to 100; As a thirteenth aspect, the method for producing a coated substrate according to any one of the seventh to twelfth aspects, wherein the substrate having a step has an open area (non-pattern area) and a pattern area consisting of DENCE (dense) and ISO (sparse), and a bias (coating step) between the open area and the pattern area is 1 nm to 50 nm. as a fourteenth aspect, a method for manufacturing a semiconductor device, comprising the steps of: forming an underlayer film made of the uneven substrate coating composition according to any one of the first to sixth aspects on a substrate having steps; forming a resist film thereon; subsequently irradiating the resist film with light or an electron beam, or heating the resist film during or after the irradiation with light or an electron beam, and then developing the resist film to form a resist pattern; etching the underlayer film using the formed resist pattern; and processing a semiconductor substrate using the patterned underlayer film; As a fifteenth aspect, the method for producing a semiconductor device according to the fourteenth aspect, wherein the step of forming an underlayer film comprises step (i) of applying the stepped substrate covering composition according to any one of the first to sixth aspects to the substrate having the step, and step (ii) of exposing or heating the composition applied in step (i); According to a sixteenth aspect, the method for producing a semiconductor device according to the fifteenth aspect further comprises, in the step (i), a step (ia) of heating the stepped substrate coating composition on the substrate having steps at a temperature of 70° C. to 400° C. for 10 seconds to 5 minutes before the exposing step (ii). As a seventeenth aspect, the method for manufacturing a semiconductor device according to the fifteenth or sixteenth aspect, wherein in the step (ii), the light used for exposure has a wavelength of 150 nm to 700 nm; According to an eighteenth aspect, in the step (ii), the exposure light amount is 10 mJ / cm 2 ~5000mJ / cm 2 The method for manufacturing a semiconductor device according to any one of the fifteenth to seventeenth aspects, According to a nineteenth aspect, there is provided the method for manufacturing a semiconductor device according to the fifteenth aspect, wherein in step (ii), heating is performed at a temperature of 100° C. to 500° C.; As a twentieth aspect, the method for manufacturing a semiconductor device according to any one of the fourteenth to nineteenth aspects, wherein the substrate having the step has an open area (non-pattern area) and a pattern area consisting of DENCE (dense) and ISO (sparse), and the aspect ratio of the pattern is 0.1 to 100; As a 21st aspect, the method for manufacturing a semiconductor device according to any one of the 14th to 20th aspects, wherein the substrate having a step has an open area (non-pattern area) and a pattern area consisting of DENCE (dense) and ISO (coarse), and an underlayer film obtained from the stepped substrate coating composition has a bias (coating step) between the open area and the pattern area of 1 nm to 50 nm. as a 22nd aspect, a method for manufacturing a semiconductor device, comprising the steps of: forming an underlayer film made of the uneven substrate coating composition according to any one of the first to sixth aspects on a substrate having steps; forming a hard mask thereon; further forming a resist film thereon; subsequently irradiating the resist film with light or an electron beam, or heating the resist film during or after the light or electron beam irradiation, and then developing the resist film to form a resist pattern; etching the hard mask using the formed resist pattern; etching the underlayer film using the patterned hard mask; and processing a semiconductor substrate using the patterned underlayer film; According to a 23rd aspect, there is provided a method for producing a semiconductor device according to the 22nd aspect, wherein the step of forming an underlayer film comprises a step (i) of applying the stepped substrate covering composition according to any one of the first to sixth aspects to the substrate having the steps, and a step (ii) of exposing or heating the composition applied in the step (i); According to a 24th aspect, the method for producing a semiconductor device according to the 23rd aspect further comprises, in the step (i), a step (ia) of heating the stepped substrate coating composition on the substrate having steps at a temperature of 70° C. to 400° C. for 10 seconds to 5 minutes before the exposing step (ii). According to a 25th aspect, there is provided a method for manufacturing a semiconductor device according to the 23rd or 24th aspect, in which the light used for exposure in the step (ii) has a wavelength of 150 nm to 700 nm. According to a 26th aspect, in the step (ii), the exposure light amount is 10 mJ / cm 2 ~5000mJ / cm 2 The method for manufacturing a semiconductor device according to any one of the twenty-third to twenty-fifth aspects, According to a 27th aspect, in the method for manufacturing a semiconductor device according to the 23rd aspect, in the step (ii), heating is performed at a temperature of 100° C. to 500° C.; As a 28th aspect, the method for manufacturing a semiconductor device according to any one of the 22nd to 27th aspects, wherein the substrate having the step has an open area (non-pattern area) and a pattern area consisting of DENCE (dense) and ISO (coarse), and the aspect ratio of the pattern is 0.1 to 100; and As a 29th aspect, there is provided a method for manufacturing a semiconductor device according to any one of the 22nd to 28th aspects, wherein the substrate having a step has an open area (non-pattern area) and a pattern area consisting of DENCE (dense) and ISO (coarse), and the underlayer film obtained from the stepped substrate coating composition has a bias (coating step) between the open area and the pattern area of 1 nm to 50 nm. [Effects of the Invention]

[0014] When the uneven substrate coating composition of the present invention is cured by light irradiation, it is first heated at a low temperature, so a crosslinking reaction does not occur at that temperature. In other words, sufficient planarization is achieved on uneven substrates. Further, by curing with light, a good planarizing film can be obtained. Furthermore, when curing is performed by heating alone, the crosslinking initiation temperature of the crosslinking groups in the polymer is high, so the crosslinking reaction begins after sufficient reflow at a high temperature, resulting in a good planarizing film.

[0015] Furthermore, the uneven substrate coating composition of the present invention can be applied to an uneven substrate to form a flat film regardless of whether the uneven substrate has an open area (non-pattern area) or a pattern area consisting of DENCE (dense) and ISO (sparse). Furthermore, the uneven substrate coating film (flattened film) formed by the uneven substrate coating composition of the present invention does not require a crosslinking agent, so a crosslinking reaction between the crosslinking agent and an acid catalyst does not occur during thermal reflow. Furthermore, when exposed to light, curing is a photoreaction that does not involve degassing, so thermal shrinkage does not occur.

[0016] In other words, the composition for covering an uneven substrate of the present invention can provide an excellent planarized film that simultaneously satisfies both good pattern filling properties and flatness after filling.

[0017] Furthermore, the step-like substrate coating composition of the present invention can be cured by heating or exposure to light. In particular, the fact that it can be cured by heating alone is convenient in operation and can increase production efficiency. DETAILED DESCRIPTION OF THE INVENTION

[0018] The present invention provides a coating composition for uneven substrates, comprising a compound (A) as a main component and a solvent, wherein the compound (A) is represented by the following formula (A-1), formula (A-2) or formula (A-3): [ka] [ka] (In the formula, the dashed line indicates a bond to an aromatic ring, and the aromatic ring is an aromatic ring constituting the polymer skeleton or an aromatic ring constituting the monomer, and n is an integer of 1 or 2.) [ka] (in the formula, the chain line represents a bond to the linear carbon chain, alicyclic carbon ring, or aromatic ring that constitutes the polymer skeleton; Q represents a single bond, or an organic group having an ether bond, ester bond, urethane bond, alkylene bond having 1 to 3 carbon atoms, or amide bond; and m represents 1. However, formula (A-1) is not included in formula (A-3),) and the composition for covering uneven substrates is cured by light irradiation or heat.

[0019] In formula (A-1), n represents an integer of 1 or 2, and the dashed line represents a bond to an aromatic ring, which is an aromatic ring constituting the polymer skeleton or an aromatic ring constituting a monomer.

[0020] The aromatic ring can be a benzene ring, a naphthalene ring, or an anthracene ring.

[0021] The polymer containing an aromatic ring can be a polymer in which the hydroxyl group of a polymer containing a hydroxyaryl novolac structure is substituted with a partial structure of formula (A-1) or a partial structure of formula (A-2). These aryl groups can be aromatic groups derived from benzene or naphthalene. Such polymers are not limited, but examples include the following:

[0022] [ka]

[0023] [ka]

[0024] [ka]

[0025] [ka]

[0026] The polymers of formula (a-1) to formula (a-13) can be synthesized by any known method, for example, by subjecting the epoxy group of the precursor polymer to a condensation reaction with 2-furancarboxylic acid, although the method is not limited thereto.

[0027] The weight average molecular weight of the polymer is 600 to 1,000,000, or 600 to 200,000, or 1,500 to 15,000.

[0028] In the present invention, the aromatic ring-containing monomer may be a monomer in which the glycidyl ether group of the aromatic ring is substituted with a partial structure of formula (A-1) or a partial structure of formula (A-2). Such monomers are not limited, but examples thereof include the following:

[0029] [ka]

[0030] [ka]

[0031] [ka]

[0032] [ka]

[0033] The monomer compounds of formulae (aa-1) to (aa-18) are synthesized by substituting the epoxy group of the precursor monomer by condensation with 2-furancarboxylic acid.

[0034] The aromatic ring-containing monomers may have a molecular weight in the range of 200 to 10,000, or 200 to 2,000, or 200 to 1,000.

[0035] In formula (A-3), the chain line represents a bond to the linear carbon chain, alicyclic carbon ring, or aromatic ring that constitutes the polymer skeleton. Q represents a single bond, or an organic group having an ether bond, ester bond, urethane bond, alkylene bond having 1 to 3 carbon atoms, or amide bond, etc. However, formula (A-3) does not include formula (A-1). m represents 1.

[0036] The bonding methods of the ether bond (-O-), ester bond (-COO-), urethane bond (-NHCOO-), alkylene bond having 1 to 3 carbon atoms (-CH-, -CHCH-, -CHCHCH-), and amide bond (-CONH-) mentioned above can be applied in any manner, whether it is a method of directly bonding the polymer skeleton and furan or a method of using an organic group containing the linking group.

[0037] When synthesizing the polymer compound represented by formula (A-3), other copolymerizable monomers can be used together with the raw material monomers to produce a copolymer, which can be used as the polymer compound of the present invention. Examples of such copolymerizable monomers include addition-polymerizable monomers such as acrylic acid esters, methacrylic acid esters, acrylamides, methacrylamides, vinyl compounds, styrene, maleimides, maleic anhydrides, and acrylonitrile. In this case, the mass ratio of the unit structure represented by formula (A-3) to the unit structure of the addition-polymerizable monomer in the resulting polymer compound is 10 / 1 to 1 / 10, 5 / 1 to 1 / 5, or 3 / 1 to 1 / 3.

[0038] The weight average molecular weight (standard polystyrene equivalent) of the polymer compound is 100 or more, for example, 1000 to 200000, or 1500 to 50000, or 3000 to 50000, or 4000 to 30000. Examples of these polymer compounds include the following:

[0039] [ka]

[0040] [ka]

[0041] [ka]

[0042] [ka]

[0043] The present invention can contain an acid generator, which can be a photoacid generator or a thermal acid generator. Examples of photoacid generators include onium salt-based photoacid generators such as bis(4-t-butylphenyl)iodonium trifluoromethanesulfonate and triphenylsulfonium trifluoromethanesulfonate, halogen-containing compound-based photoacid generators such as phenyl-bis(trichloromethyl)-s-triazine, and sulfonic acid-based photoacid generators such as benzoin tosylate and N-hydroxysuccinimide trifluoromethanesulfonate. The amount of the photoacid generator is 0.2 to 5% by mass, or 0.4 to 5% by mass, or 0.4 to 4.9% by mass, or 0.4 to 4.8% by mass, based on the total solids content. Examples of thermal acid generators include 2,4,4,6-tetrabromocyclohexanedienone, benzoin tosylate, 2-nitrobenzyl tosylate, pyridinium p-toluenesulfonate, pyridinium p-hydroxybenzenesulfonate, other organic sulfonic acid alkyl esters, and salts thereof. Commercially available products include K-PURE (registered trademark) CXC-1612, CXC-1614, CXC-1742, CXC-1802, TAG-2678, TAG2681, TAG2689, TAG2690, and TAG2700 (manufactured by King Industries), and SI-45, SI-60, SI-80, SI-100, SI-110, and SI-150 (manufactured by Sanshin Chemical Industry Co., Ltd.). These thermal acid generators can be used alone or in combination of two or more. The content of the thermal acid generator is, for example, 0.01 to 20% by mass, preferably 0.1 to 10% by mass, based on the total mass of the furan compound (A).

[0044] The coating composition for uneven substrates of the present invention may contain a surfactant. Examples of the surfactant include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, and polyoxyethylene oleyl ether; polyoxyethylene alkylaryl ethers such as polyoxyethylene octylphenyl ether and polyoxyethylene nonylphenyl ether; polyoxyethylene-polyoxypropylene block copolymers; sorbitan fatty acid esters such as sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, and sorbitan tristearate; polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, and polyoxyethylene sorbitan monostearate; nonionic surfactants such as polyoxyethylene sorbitan fatty acid esters such as polyoxyethylene sorbitan trioleate, polyoxyethylene sorbitan tristearate, etc.; F-Top (registered trademark) EF301, EF303, EF352 (manufactured by Mitsubishi Materials Electronic Chemicals Co., Ltd.); Megafac (registered trademark) F171, F173, R30, R-30N, R-40, R-4 Examples of such surfactants include fluorine-based surfactants such as OL M (manufactured by DIC Corporation), Fluorad FC430, FC431 (manufactured by Sumitomo 3M Limited), Asahiguard (registered trademark) AG710, Surflon (registered trademark) S-382, SC101, SC102, SC103, SC104, SC105, and SC106 (manufactured by Asahi Glass Co., Ltd.), and organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.). One selected from these surfactants may be added, or two or more may be added in combination. The content of the surfactant is, for example, 0.01 to 5% by mass, or 0.01 to 2% by mass, or 0.01 to 0.2% by mass, or 0.01 to 0.1% by mass, or 0.01 to 0.09% by mass, based on the solid content of the step substrate covering composition of the present invention excluding the solvent described below.

[0045] Examples of the solvent for dissolving compound (A) in the present invention include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoisopropyl ether, ethylene glycol methyl ether acetate, ethylene glycol ethyl ether acetate, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monoethyl ether acetate, propylene glycol, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether, propylene glycol monoethyl ether acetate, propylene glycol propyl ether acetate, and dipropylene glycol. Glycol monomethyl ether, dipropylene glycol monoethyl ether, triethylene glycol dimethyl ether, toluene, xylene, styrene, methyl ethyl ketone, cyclopentanone, cyclohexanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, 1-octanol, ethylene glycol, hexylene glycol, trimethylene glycol, 1-methoxy-2-butanol, cyclohexanol, diacetone alcohol, furfuryl alcohol, tetrahydrofurfuryl alcohol, propylene glycol, benzyl alcohol, 1,3-butanediol, 1,4-butanediol, 2,Examples of organic solvents that can be used include 3-butanediol, γ-butyl lactone, acetone, methyl isopropyl ketone, diethyl ketone, methyl isobutyl ketone, methyl normal butyl ketone, isopropyl acetate ketone, normal propyl acetate, isobutyl acetate, methanol, ethanol, isopropanol, tert-butanol, allyl alcohol, normal propanol, 2-methyl-2-butanol, isobutanol, normal butanol, 2-methyl-1-butanol, 1-pentanol, 2-methyl-1-pentanol, 2-ethylhexanol, isopropyl ether, 1,4-dioxane, N,N-dimethylacetamide, N,N-dimethylacetamide, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, dimethyl sulfoxide, and N-cyclohexyl-2-pyrrolidinone. These organic solvents can be used alone or in combination of two or more.

[0046] Next, the method for forming a planarized film using the uneven substrate coating composition of the present invention will be described. The uneven substrate coating composition is applied to a substrate used in the manufacture of precision integrated circuit devices (e.g., a transparent substrate such as a silicon / silicon dioxide-coated substrate, a glass substrate, or an ITO substrate) using an appropriate coating method such as a spinner or coater, and then baked (heated) or exposed to light to form a coating. That is, the coated substrate is produced by the following steps: step (i) of applying the uneven substrate coating composition to a substrate having steps, and step (ii) of exposing or heating the composition applied in step (i).

[0047] When applying using a spinner, the application can be carried out at a rotation speed of 100 to 5000 for 10 to 180 seconds, for example.

[0048] The substrate has an open area (non-patterned area) and a patterned area consisting of DENCE (dense) and ISO (coarse), and the aspect ratio of the pattern is 0.1 to 10, or 0.1 to 100.

[0049] A non-patterned area refers to a portion of the substrate where there are no patterns (e.g., holes or trench structures), a dense area refers to a portion of the substrate where patterns are densely packed, and a coarse area refers to a portion of the substrate where patterns are widely spaced and scattered. The aspect ratio of a pattern is the ratio of the pattern depth to the pattern width. The pattern depth is typically several hundred nanometers (e.g., about 100 to 300 nm), and a dense area refers to a portion where patterns of several tens of nanometers (e.g., about 30 to 80 nm) are densely packed at intervals of about 100 nm. An coarse area refers to a portion where patterns of several hundred nanometers (e.g., about 200 to 1000 nm) are scattered.

[0050] Here, the thickness of the uneven substrate coating film (planarizing film) is preferably 0.01 μm to 3.0 μm. In step (ia), the coating composition can be heated after application and before light irradiation at 70° C. to 400° C., or 100° C. to 250° C. for 10 seconds to 5 minutes, or 30 seconds to 2 minutes. This heating causes the uneven substrate coating composition to reflow, forming a flat uneven substrate coating film (planarizing film).

[0051] In step (ii), the exposure light is actinic radiation such as near ultraviolet light or far ultraviolet light, and light with wavelengths of, for example, 248 nm (KrF laser light), 193 nm (ArF laser light), 172 nm (xenon excimer light), 157 nm (F2 laser light), etc. The exposure wavelength may be ultraviolet light of 150 nm to 700 nm, with a wavelength of 172 nm being preferred.

[0052] This exposure causes crosslinking of the film covering the stepped substrate (flattening film). In step (ii), the exposure dose is 10 mJ / cm 2 2 ~3000mJ / cm 2 , or 10 mJ / cm 2 ~5000mJ / cm 2 Within this range of exposure light amount, a photoreaction occurs, crosslinking is formed, and solvent resistance is achieved.

[0053] In step (ii), the uneven substrate coating film (flattening film) can be crosslinked by heating alone, without light irradiation. Heating is preferably performed at a temperature of 100°C to 500°C, or 200°C to 400°C. At temperatures within this range, acid is generated, causing a curing reaction, resulting in solvent resistance.

[0054] The stepped substrate coating film (planarizing film) formed in this manner preferably has zero bias (coating step) between the open area and the pattern area, but can be planarized to a range of 1 nm to 50 nm, or 1 nm to 25 nm. The bias between the open area and the DENCE area is about 15 nm to 20 nm, and the bias between the open area and the ISO area is about 1 nm to 10 nm.

[0055] The uneven substrate coating film (planarizing film) obtained by the present invention can be coated with a resist film, and the resist film can be exposed and developed by lithography to form a resist pattern, and the substrate can be processed according to the resist pattern. In this case, the uneven substrate coating film (planarizing film) serves as a resist underlayer film, and the uneven substrate coating composition also serves as a resist underlayer film-forming composition.

[0056] A good resist pattern can be obtained by applying a resist to the resist underlayer film, irradiating it with light or an electron beam through a predetermined mask, developing, rinsing, and drying. If necessary, post-exposure baking (PEB) can also be performed. The resist underlayer film in the areas where the resist film has been developed and removed in the above process is then removed by dry etching, allowing the desired pattern to be formed on the substrate.

[0057] The resist used in the present invention is a photoresist or an electron beam resist.

[0058] The photoresist to be applied on top of the resist underlayer film for lithography in the present invention may be either a negative or positive type, and examples thereof include a positive photoresist composed of a novolak resin and a 1,2-naphthoquinone diazide sulfonic acid ester; a chemically amplified photoresist composed of a binder having a group that is decomposed by acid to increase the alkaline dissolution rate and a photoacid generator; a chemically amplified photoresist composed of an alkali-soluble binder, a low molecular weight compound that is decomposed by acid to increase the alkaline dissolution rate of the photoresist and a photoacid generator; a chemically amplified photoresist composed of a binder having a group that is decomposed by acid to increase the alkaline dissolution rate and a low molecular weight compound that is decomposed by acid to increase the alkaline dissolution rate of the photoresist and a photoacid generator; and a photoresist having Si atoms in its skeleton, such as APEX-E, a product of Rohm and Haas.

[0059] Examples of the electron beam resist to be applied on top of the resist underlayer film for lithography in the present invention include a composition comprising a resin containing a Si-Si bond in the main chain and an aromatic ring at the terminal, and an acid generator that generates acid upon irradiation with an electron beam, or a composition comprising poly(p-hydroxystyrene) in which the hydroxyl group is substituted with an organic group containing N-carboxyamine, and an acid generator that generates acid upon irradiation with an electron beam. In the latter electron beam resist composition, the acid generated from the acid generator upon irradiation with an electron beam reacts with the N-carboxyaminooxy group in the polymer side chain, decomposing the polymer side chain into a hydroxyl group, making it alkali-soluble and dissolving in an alkaline developer, thereby forming a resist pattern. Acid generators that generate acid upon irradiation with an electron beam include halogenated organic compounds such as 1,1-bis[p-chlorophenyl]-2,2,2-trichloroethane, 1,1-bis[p-methoxyphenyl]-2,2,2-trichloroethane, 1,1-bis[p-chlorophenyl]-2,2-dichloroethane, and 2-chloro-6-(trichloromethyl)pyridine; onium salts such as triphenylsulfonium salts and diphenyliodonium salts; and sulfonic acid esters such as nitrobenzyl tosylate and dinitrobenzyl tosylate.

[0060] The exposure light for the photoresist is actinic radiation such as near ultraviolet, far ultraviolet, or extreme ultraviolet (e.g., EUV, wavelength 13.5 nm), and light with wavelengths of, for example, 248 nm (KrF laser light), 193 nm (ArF laser light), or 172 nm is used. For light irradiation, any method can be used without particular limitation as long as it can generate acid from the photoacid generator in the resist film, and the exposure light dose is 1 to 5000 mJ / cm. 2 , or 10 to 5000 mJ / cm 2 , or 10 to 1000 mJ / cm 2 by.

[0061] The electron beam resist can be irradiated with electron beams using, for example, an electron beam irradiation device.

[0062] Developers for resist films having a resist underlayer film formed using the stepped substrate coating composition of the present invention include aqueous solutions of alkalis such as inorganic alkalis (e.g., sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia), primary amines (e.g., ethylamine and n-propylamine), secondary amines (e.g., diethylamine and di-n-butylamine), tertiary amines (e.g., triethylamine and methyldiethylamine), alcohol amines (e.g., dimethylethanolamine and triethanolamine), quaternary ammonium salts (e.g., tetramethylammonium hydroxide, tetraethylammonium hydroxide, and choline), and cyclic amines (e.g., pyrrole and piperidine). Furthermore, aqueous solutions of the alkalis described above can be used by adding an appropriate amount of alcohols (e.g., isopropyl alcohol) or a nonionic surfactant. Among these, preferred developers are quaternary ammonium salts, more preferably tetramethylammonium hydroxide and choline.

[0063] An organic solvent can be used as the developer, for example, methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, ethyl methoxyacetate, ethyl ethoxyacetate, propylene glycol monomethyl ether, ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol monobutyl ether acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-ethyl-3-methoxybutyl acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, 2-ethoxybutyl ether ...2-ethoxybutyl ether acetate, 2-ethoxybutyl ether acetate, 2-ethoxybutyl ether acetate, 2-ethoxybutyl ether acetate, 2-ethoxybutyl ether acetate, 2-ethoxybutyl ether acetate, 2-ethoxybutyl ether acetate, 2-ethoxybutyl ether acetate, 2-ethoxybutyl ether acetate, 2-ethoxybutyl ether acetate, 2 Dibutyl acetate, 4-ethoxybutyl acetate, 4-propoxybutyl acetate, 2-methoxypentyl acetate, 3-methoxypentyl acetate, 4-methoxypentyl acetate, 2-methyl-3-methoxypentyl acetate, 3-methyl-3-methoxypentyl acetate, 3-methyl-4-methoxypentyl acetate, 4-methyl-4-methoxypentyl acetate, propylene glycol diacetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, propyl lactate, charcoal Examples of the alkyl esters include ethyl acetate, propyl carbonate, butyl carbonate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl-3-methoxypropionate, ethyl-3-methoxypropionate, ethyl-3-ethoxypropionate, and propyl-3-methoxypropionate.Furthermore, a surfactant may be added to these developers. The development conditions are appropriately selected from a temperature of 5 to 50° C. and a time of 10 to 600 seconds.

[0064] In the present invention, a semiconductor device can be manufactured through the steps of forming a resist underlayer film on a semiconductor substrate using a resist underlayer film-forming composition, forming a resist film thereon, subsequently forming a resist pattern by irradiating the resist film with light or an electron beam and developing it, etching the resist underlayer film using the resist pattern, and processing a semiconductor substrate using the patterned resist underlayer film.

[0065] As resist patterns become increasingly finer, problems such as resolution and the collapse of resist patterns after development will arise, necessitating thinner resists. As a result, it is difficult to obtain resist patterns thick enough for substrate processing. This has led to the need for processes in which not only the resist pattern but also the resist underlayer film formed between the resist film and the semiconductor substrate to be processed functions as a mask during substrate processing. For these processes, resist underlayer films, unlike conventional high-etch-rate resist underlayer films, are increasingly required, including lithography resist underlayer films with dry etching selectivities similar to those of resist films, those with dry etching selectivities lower than those of resist films, and those with dry etching selectivities lower than those of semiconductor substrates. Furthermore, such resist underlayer films can be imparted with antireflective properties, thereby combining the functionality of conventional antireflective films.

[0066] On the other hand, in order to obtain fine resist patterns, a process has begun to be used in which the resist pattern and the resist underlayer film are made narrower during dry etching than the pattern width during resist development. For resist underlayer films used in such processes, there is a growing demand for resist underlayer films that have a dry etching rate selectivity similar to that of the resist film, unlike conventional high-etch-rate antireflective films. Furthermore, such resist underlayer films can also be imparted with antireflective properties, allowing them to possess the functions of conventional antireflective films.

[0067] In the present invention, after the resist underlayer film of the present invention is formed on a substrate, a resist can be applied directly onto the resist underlayer film, or after one or several layers of a coating material are formed on the resist underlayer film as needed. This narrows the pattern width of the resist film, and even if a thin resist film is applied to prevent pattern collapse, it becomes possible to process the substrate by selecting an appropriate etching gas.

[0068] That is, a semiconductor device can be manufactured through the following steps: forming a resist underlayer film on a semiconductor substrate using a resist underlayer film-forming composition; forming a hard mask thereon using a coating material containing a silicon component or the like or a hard mask by vapor deposition (e.g., silicon nitride oxide); forming a resist film thereon; forming a resist pattern by irradiation with light or an electron beam and development; etching the hard mask using the resist pattern with a halogen-based gas; etching the resist underlayer film using an oxygen-based gas or a hydrogen-based gas using the patterned hard mask; and processing the semiconductor substrate with a halogen-based gas using the patterned resist underlayer film.

[0069] When the effect of the coating composition for uneven substrates of the present invention as an anti-reflection film is taken into consideration, the light-absorbing moiety is incorporated into the skeleton, so that no matter diffuses into the photoresist during heating and drying, and the light-absorbing moiety has sufficiently high light-absorbing performance, so that the coating composition for uneven substrates of the present invention has a high anti-reflection effect.

[0070] The coating composition for uneven substrates of the present invention has high thermal stability, prevents contamination of the upper layer film by decomposition products during firing, and allows for a large temperature margin in the firing step.

[0071] Furthermore, depending on the process conditions, the composition for coating a stepped substrate of the present invention can be used as a film having the function of preventing light reflection and further the function of preventing interaction between the substrate and the photoresist or preventing adverse effects on the substrate of materials used in the photoresist or substances generated during exposure of the photoresist. [Example]

[0072] <Synthesis Example 1> In a two-necked flask Furfuryl methacrylate (Tokyo Chemical Industry Co., Ltd.) 5g, methyl methacrylate (Tokyo Chemical Industry Co., Ltd.) 3.01g, 2,2 ’- 0.42 g of azobis(methyl isobutyrate) (Tokyo Chemical Industry Co., Ltd.) and 48 g of propylene glycol monomethyl ether acetate were added. The mixture was then heated to 120°C and stirred for approximately 6 hours. After the reaction was completed, the polymer solution was added dropwise to methanol (Kanto Chemical Co., Ltd.) to cause reprecipitation. The resulting precipitate was filtered by suction, and the residue was dried under reduced pressure at 60°C overnight. 5 g of Compound 1 resin was obtained. The weight-average molecular weight Mw of the resulting compound, estimated by GPC in terms of polystyrene, was 6,500.

[0073] [ka]

[0074] <Synthesis Example 2> A two-neck flask was charged with 7 g of JER-1031S (Mitsubishi Chemical Corporation) (tetraphenylethane-type epoxy resin), 4.1 g of 2-furancarboxylic acid (Tokyo Chemical Industry Co., Ltd.), 0.006 g of tetrabutylphosphonium bromide (Tokyo Chemical Industry Co., Ltd.), and 26 g of propylene glycol monomethyl ether acetate. The mixture was then heated to 100°C and stirred for approximately 6 hours. To the resulting solution, 11 g of cation exchange resin (Dowex® 550A, Muromachi Technos Co., Ltd.) and 11 g of anion exchange resin (Urban Light® 15JWET, Organo Corporation) were added, and the mixture was subjected to ion exchange treatment at room temperature for 4 hours. After separating the ion exchange resin, a solution of Compound 2 was obtained. The weight-average molecular weight (Mw) of the resulting compound measured by GPC in terms of polystyrene was 1600.

[0075] [ka]

[0076] <Comparative Synthesis Example 3> In a two-neck flask, 40.0 g of EHPE3150 (Daicel Chemical Industries, Ltd.) (1,2-epoxy-4-(2-oxiranyl)cyclohexane adduct of 2,2-bis(hydroxymethyl)-1-butanol), 20.3 g of 9-anthracenecarboxylic acid, and 13.7 g of benzoic acid were dissolved in 302.0 g of propylene glycol monomethyl ether, followed by the addition of 1.5 g of benzyltriethylammonium and refluxing for 24 hours. The resulting solution was added with 11 g of cation exchange resin (Dowex® 550A, Muromachi Technos Co., Ltd.) and 11 g of anion exchange resin (Urban Light® 15JWET, Organo Corporation), and the mixture was subjected to ion exchange treatment at room temperature for 4 hours. After separating the ion exchange resin, Compound 3 solution was obtained. The weight-average molecular weight (Mw) of the resulting compound measured by GPC in terms of polystyrene was 4,100.

[0077] [ka]

[0078] Example 1 0.95 g of the resin obtained in Synthesis Example 1 was mixed with 0.95 g of propylene glycol monomethyl ether containing 5% TPS-Tf (photoacid generator, manufactured by Toyo Gosei Co., Ltd.), 0.09 g of propylene glycol monomethyl ether acetate containing 1% surfactant (fluorosurfactant, product name: Megafac [product name] R-40, manufactured by DIC Corporation), 1.8 g of propylene glycol monomethyl ether, and 6.2 g of propylene glycol monomethyl ether acetate. The mixture was then filtered through a 0.1 μm diameter polytetrafluoroethylene microfilter to prepare a solution of a resist underlayer film-forming composition.

[0079] <Example 2> 8.4 g of the resin solution (solid content 20.4%) obtained in Synthesis Example 2 was mixed with 1.71 g of propylene glycol monomethyl ether containing 5% TPS-Tf (photoacid generator, manufactured by Toyo Gosei Co., Ltd.), 0.17 g of propylene glycol monomethyl ether acetate containing 1% surfactant (fluorosurfactant, product name: Megafac [product name] R-40, manufactured by DIC Corporation), 2.4 g of propylene glycol monomethyl ether, and 2.3 g of propylene glycol monomethyl ether acetate. The mixture was then filtered through a polytetrafluoroethylene microfilter with a pore size of 0.1 μm to prepare a solution of a resist underlayer film-forming composition.

[0080] Example 3 8.4 g of the resin solution (solid content 20.4%) obtained in Synthesis Example 2 was mixed with 1.71 g of propylene glycol monomethyl ether containing 5% TAG2689 (trade name, manufactured by King Chemical Industries, Ltd., USA, component: quaternary ammonium salt of trifluoromethanesulfonic acid), 0.17 g of propylene glycol monomethyl ether acetate containing 1% surfactant (manufactured by DIC Corporation, product name: Megafac [trade name] R-40, fluorine-based surfactant), 2.4 g of propylene glycol monomethyl ether, and 2.3 g of propylene glycol monomethyl ether acetate. The mixture was then filtered through a polytetrafluoroethylene microfilter with a pore size of 0.1 μm to prepare a solution of a resist underlayer film-forming composition.

[0081] Example 4 8.4 g of the resin solution (solid content 20.4%) obtained in Synthesis Example 2 was mixed with 1.71 g of propylene glycol monomethyl ether containing 5% pyridinium p-hydroxybenzenesulfonate, 0.17 g of propylene glycol monomethyl ether acetate containing 1% of a surfactant (manufactured by DIC Corporation, product name: Megafac [product name] R-40, fluorine-based surfactant), 2.4 g of propylene glycol monomethyl ether, and 2.3 g of propylene glycol monomethyl ether acetate. The mixture was then filtered through a polytetrafluoroethylene microfilter with a pore size of 0.1 μm to prepare a solution of a resist underlayer film-forming composition.

[0082] <Comparative Example 1> 1.0 g of the resin obtained in Synthesis Example 1 was mixed with 0.1 g of propylene glycol monomethyl ether acetate containing 1% of a surfactant (manufactured by DIC Corporation, product name: Megafac [product name] R-40, fluorine-based surfactant), 2.7 g of propylene glycol monomethyl ether, and 6.2 g of propylene glycol monomethyl ether acetate. The mixture was then filtered through a polytetrafluoroethylene microfilter with a pore size of 0.1 μm to prepare a solution of a resist underlayer film-forming composition.

[0083] <Comparative Example 2> 8.8 g of the resin obtained in Synthesis Example 2 was mixed with 0.2 g of propylene glycol monomethyl ether acetate containing 1% of a surfactant (manufactured by DIC Corporation, product name: Megafac [product name] R-40, fluorine-based surfactant), 2.1 g of propylene glycol monomethyl ether, and 4.0 g of propylene glycol monomethyl ether acetate. The mixture was then filtered through a polytetrafluoroethylene microfilter with a pore size of 0.1 μm to prepare a solution of a resist underlayer film-forming composition.

[0084] <Comparative Example 3> 0.2 g of tetramethoxymethyl glycoluril, 0.2 g of propylene glycol monomethyl ether containing 5% pyridinium p-toluenesulfonate, 0.08 g of propylene glycol monomethyl ether acetate containing 1% of a surfactant (manufactured by DIC Corporation, product name: Megafac [product name] R-40, a fluorine-based surfactant), 2.1 g of propylene glycol monomethyl ether, and 2.6 g of propylene glycol monomethyl ether acetate were mixed with 4.9 g of the resin solution obtained in Comparative Synthesis Example 3 (solid content: 16.0%). The mixture was then filtered through a polytetrafluoroethylene microfilter having a pore size of 0.1 μm to prepare a solution of a resist underlayer film-forming composition.

[0085] (Thermosetting test) The resist underlayer film compositions prepared in Examples 3 and 4 and Comparative Examples 1 and 2 were each applied to a silicon wafer using a spin coater. The coating was heated on a hot plate at 300°C for 60 minutes to form a resist underlayer film with a thickness of 200 nm. Solvent strippability was evaluated by immersing the baked coating film in a 7:3 mixed solvent of propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate for 1 minute, spin-drying, and baking at 100°C for 60 seconds. The film thickness was measured, and the remaining film ratio was calculated (Table 1). In Examples 3 and 4, a curing reaction occurred due to the effect of acid generated by heat, resulting in resistance to solvents and a film remaining rate of 100%, whereas in Comparative Examples 1 and 2, the film remaining rate was 0%.

[0086] [Table 1]

[0087] (Photocuring test) The resist underlayer film compositions prepared in Examples 1 and 2 and Comparative Examples 1 and 2 were each applied onto a silicon wafer using a spin coater. The wafer was heated on a hot plate at 170°C for 60 seconds to form a resist underlayer film with a thickness of 150 nm. This resist underlayer film was then exposed to 500 mJ / cm 2 UV irradiation using a UV irradiation unit (172 nm) manufactured by Ushio Inc. 2 After UV irradiation, the film was heated on a hot plate at 160°C for 60 seconds to check solvent removability under light irradiation (UV irradiation). Solvent removability was measured by immersing the UV-irradiated coating film for 1 minute in a 7:3 mixed solvent of propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate, spin-drying it, and then baking it at 100°C for 60 seconds. The film thickness was measured and the remaining film rate was calculated (Table 2). In Examples 1 and 2, a curing reaction occurred due to the effect of acid generated by light, resulting in resistance to solvents and a film remaining rate of 100%, whereas in Comparative Examples 1 and 2, the film remaining rate was 0%.

[0088] [Table 2]

[0089] (Evaluation of flattening and embedding properties on uneven substrates) To evaluate the planarization ability on uneven substrates, a comparison was made between the coating thickness of a dense pattern area (DENSE) with a trench width of 50 nm and a pitch of 100 nm on a 200 nm thick SiO2 substrate and an open area (OPEN) where no pattern was formed. The resist underlayer film compositions prepared in Examples 1 and 2 were applied to the substrates using a spin coater, and then heated on a hot plate at 170°C for 60 seconds to form resist underlayer films with film thicknesses of 150 nm and 200 nm. These resist underlayer films were then exposed to 500 mJ / cm using an ultraviolet irradiation device using a UV irradiation unit (172 nm) manufactured by Ushio Inc.2 After irradiating the substrate with ultraviolet light, the substrate was heated on a hot plate at 160°C for 60 seconds. The resist underlayer film compositions prepared in Examples 3, 4, and Comparative Example 3 were each applied to the substrate using a spin coater and then heated on a hot plate at 215°C and 300°C for 60 seconds. The planarization properties of these substrates were observed using a scanning electron microscope (S-4800) manufactured by Hitachi High-Technologies Corporation, and the planarization properties were evaluated by measuring the film thickness difference between the dense area (pattern area) and the open area (non-pattern area) of the uneven substrate (the coating step between the dense area and the open area, referred to as bias). Here, planarization properties refer to a small difference in film thickness (iso-dense bias) between the area where the pattern is present (dense area (pattern area)) and the area where the pattern is not present (open area (non-pattern area)). (Table 3)

[0090] In Examples 1 and 2, the crosslinking reaction does not occur at 170°C, so sufficient reflowability is obtained at this stage, and sufficient planarization is achieved on uneven substrates. Furthermore, by curing with light, a good planarization film can be obtained. In Examples 3 and 4, the crosslinking group in the polymer has a high crosslinking initiation temperature, so the crosslinking reaction begins after sufficient reflow at high temperature, resulting in a good planarization film. On the other hand, in Comparative Example 3, the crosslinking initiation temperature of the crosslinking agent is low, so sufficient reflowability is not obtained, and planarization is poor.

[0091] [Table 3] [Industrial Applicability]

[0092] The coating composition for uneven substrates of the present invention has a furyl group, which allows for more stable purification with an ion exchange resin than conventional epoxy groups when synthesizing the coating composition for uneven substrates, thereby ultimately enabling the production of a high-purity coating composition for uneven substrates.Furthermore, the coating composition for uneven substrates of the present invention can be used as a coating composition for uneven substrates for forming a coating film on a substrate that has high pattern filling properties and planarizing properties.

Claims

1. A coating composition for uneven substrates, comprising a compound (A) as a main component and a solvent, but not containing a crosslinking agent or a silane compound, The compound (A) is represented by the following formula (A-1) or formula (A-3): 【Chemical 1】 (In the formula, the dashed line indicates a bond to an aromatic ring, the aromatic ring is an aromatic ring constituting the monomer, and n is an integer of 1 or 2.) 【Chemistry 2】 (in the formula, the chain line represents a bond to a linear carbon chain, alicyclic carbon ring or aromatic ring constituting the (meth)acrylic polymer skeleton; Q represents a single bond, or an organic group having an ether bond, ester bond, urethane bond, alkylene bond having 1 to 3 carbon atoms or amide bond; and m represents 1. However, formula (A-1) is not included in formula (A-3), and the composition for covering stepped substrates is cured by light irradiation or heat.

2. 2. The composition for covering stepped substrates according to claim 1, wherein the aromatic ring is a benzene ring, a naphthalene ring, or an anthracene ring.

3. The composition for covering stepped substrates according to claim 1 or 2, wherein the polymer containing an aromatic ring is a polymer containing a hydroxyaryl novolak structure, in which the hydroxyl group is substituted with a partial structure represented by formula (A-1).

4. The aromatic ring-containing monomer is such that the hydroxyl group of the aromatic ring is a group represented by the formula (A- 3. The coating composition for uneven substrates according to claim 1, wherein the monomer is substituted with the partial structure of 1).

5. The composition for covering a substrate with irregularities according to any one of claims 1 to 4, further comprising an acid generator.

6. The coating composition for a stepped substrate according to any one of claims 1 to 5, further comprising a surfactant.

7. A method for producing a coated substrate, comprising: a step (i) of applying the uneven substrate coating composition according to any one of claims 1 to 6 to a substrate having an uneven surface; and a step (ii) of exposing or heating the composition applied in step (i).

8. 8. The method for producing a coated substrate according to claim 7, further comprising the step (ia) of heating the stepped substrate coating composition on the stepped substrate at a temperature of 70°C to 400°C for 10 seconds to 5 minutes before the step (ii) of exposing.

9. 9. The method for producing a coated substrate according to claim 7, wherein the light used for exposure in the step (ii) has a wavelength of 150 nm to 700 nm.

10. In the above step (ii), the exposure light amount is 10 mJ / cm ２ ~5000mJ / cm ２ The method for producing a coated substrate according to any one of claims 7 to 9, wherein

11. 8. The method for producing a coated substrate according to claim 7, wherein the heating in step (ii) is performed at a temperature of 100 to 500°C.

12. 12. The method for producing a coated substrate according to claim 7, wherein the substrate having the step has an open area (non-pattern area) and a pattern area consisting of DENCE (dense) and ISO (coarse), and the aspect ratio of the pattern is 0.1 to 100.

13. 13. The method for producing a coated substrate according to any one of claims 7 to 12, wherein the substrate having the step has an open area (non-pattern area) and a pattern area consisting of DENCE (dense) and ISO (coarse), and the bias (coating step) between the open area and the pattern area is 1 nm to 50 nm.

14. 10. A method for manufacturing a semiconductor device, comprising the steps of: forming an underlayer film made of the uneven substrate coating composition according to claim 1 on a substrate having steps; forming a resist film thereon; irradiating the resist film with light or an electron beam, or heating the resist film during or after the irradiation with light or an electron beam, and then developing the resist film to form a resist pattern; etching the underlayer film using the formed resist pattern; and processing a semiconductor substrate with the patterned underlayer film.

15. 15. The method for manufacturing a semiconductor device according to claim 14, wherein the step of forming the underlayer film comprises step (i) of applying the stepped substrate coating composition according to any one of claims 1 to 6 to the substrate having the step, and step (ii) of exposing or heating the composition applied in step (i).

16. 16. The method for manufacturing a semiconductor device according to claim 15, further comprising the step (ia) of heating the stepped substrate coating composition on the stepped substrate at a temperature of 70°C to 400°C for 10 seconds to 5 minutes before the step (ii) of exposing the substrate to light.

17. 17. The method for manufacturing a semiconductor device according to claim 15, wherein the light used for exposure in the step (ii) has a wavelength of 150 nm to 700 nm.

18. In the above step (ii), the exposure light amount is 10 mJ / cm ２ ~5000mJ / cm ２ 18. The method for manufacturing a semiconductor device according to claim 15, wherein

19. 16. The method for manufacturing a semiconductor device according to claim 15, wherein the heating is performed at a temperature of 100 to 500[deg.] C. in the step (ii).

20. 20. A method for manufacturing a semiconductor device according to any one of claims 14 to 19, wherein the substrate having the step has an open area (non-pattern area) and a pattern area consisting of DENCE (dense) and ISO (coarse), and the aspect ratio of the pattern is 0.1 to 100.

21. 21. The method for manufacturing a semiconductor device according to claim 14, wherein the substrate having a step has an open area (non-pattern area) and a pattern area consisting of DENCE (dense) and ISO (coarse), and the underlayer film obtained from the stepped substrate coating composition has a bias (coating step) between the open area and the pattern area of 1 nm to 50 nm.

22. 10. A method for manufacturing a semiconductor device, comprising the steps of: forming an underlayer film made of the uneven substrate coating composition according to claim 1 on a substrate having steps; forming a hard mask thereon; further forming a resist film thereon; subsequently irradiating the resulting film with light or an electron beam, or heating the film during or after the light or electron beam irradiation, and then developing the resulting film to form a resist pattern; etching the hard mask using the formed resist pattern; etching the underlayer film using the patterned hard mask; and processing a semiconductor substrate using the patterned underlayer film.

23. 23. The method for manufacturing a semiconductor device according to claim 22, wherein the step of forming the underlayer film comprises step (i) of applying the stepped substrate coating composition according to any one of claims 1 to 6 to the substrate having the step, and step (ii) of exposing or heating the composition applied in step (i).

24. 24. The method for manufacturing a semiconductor device according to claim 23, further comprising the step (ia) of heating the stepped substrate coating composition on the stepped substrate at a temperature of 70°C to 400°C for 10 seconds to 5 minutes before the step (ii) of exposing.

25. 25. The method for manufacturing a semiconductor device according to claim 23, wherein in the step (ii), the light used for exposure has a wavelength of 150 nm to 700 nm.

26. In the above step (ii), the exposure light amount is 10 mJ / cm ２ ~5000mJ / cm ２ 26. The method for manufacturing a semiconductor device according to claim 23, wherein

27. 24. The method for manufacturing a semiconductor device according to claim 23, wherein the heating is performed at a temperature of 100 to 500° C. in the step (ii).

28. 28. A method for manufacturing a semiconductor device according to any one of claims 22 to 27, wherein the substrate having the step has an open area (non-pattern area) and a pattern area consisting of DENCE (dense) and ISO (coarse), and the aspect ratio of the pattern is 0.1 to 100.

29. 29. The method for manufacturing a semiconductor device according to any one of claims 22 to 28, wherein the substrate having a step has an open area (non-pattern area) and a pattern area consisting of DENCE (dense) and ISO (coarse), and the underlayer film obtained from the stepped substrate coating composition has a bias (coating step) between the open area and the pattern area of 1 nm to 50 nm.

Images