FILM-FORMING COMPOSITION

Abstract

A film-forming composition includes a solvent and hydrolysis condensate prepared through hydrolysis and condensation of a hydrolyzable silane compound by using an acidic compound containing two or more acidic groups. The hydrolyzable silane compound contains an amino-group-containing silane with formula (1). R.sup.1 is an organic group containing an amino group. R.sup.2 is a substitutable alkyl, substitutable aryl, substitutable aralkyl, substitutable halogenated alkyl, substitutable halogenated aryl, substitutable halogenated aralkyl, substitutable alkoxyalkyl, substitutable alkoxyaryl, substitutable alkoxyaralkyl, or substitutable alkenyl group, or an organic group containing an epoxy, acryloyl, methacryloyl, mercapto, or a cyano group. R.sup.3 is an alkoxy, aralkyloxy, or acyloxy group or halogen atom. a is an integer of 1 or 2, b of 0 or 1; and a and b satisfy a relation of a+b≤2.

R.sup.1.sub.aR.sup.2.sub.bSi(R.sup.3).sub.4−(a+b)  (1)

Claims

1. A film-forming composition comprising a solvent, and a hydrolysis condensate prepared through hydrolysis and condensation of a hydrolyzable silane compound by using an acidic compound containing two or more acidic groups, the film-forming composition being characterized in that: the hydrolyzable silane compound contains an amino-group-containing silane of the following Formula (1):
R.sup.1.sub.aR.sup.2.sub.bSi(R.sup.3).sub.4−(a+b)  (1) (wherein R.sup.1 is a group bonded to the silicon atom, and is each independently an organic group containing an amino group; R.sup.2 is a group bonded to the silicon atom, and is a substitutable alkyl group, a substitutable aryl group, a substitutable aralkyl group, a substitutable halogenated alkyl group, a substitutable halogenated aryl group, a substitutable halogenated aralkyl group, a substitutable alkoxyalkyl group, a substitutable alkoxyaryl group, a substitutable alkoxyaralkyl group, or a substitutable alkenyl group, or an organic group containing an epoxy group, an acryloyl group, a methacryloyl group, a mercapto group, or a cyano group; R.sup.3 is a group or atom bonded to the silicon atom, and is each independently an alkoxy group, an aralkyloxy group, an acyloxy group, or a halogen atom; a is an integer of 1 or 2; b is an integer of 0 or 1; and a and b satisfy a relation of a+b≤2).

2. The film-forming composition according to claim 1, wherein the two or more acidic groups contain two or more mutually different groups selected from the group consisting of a sulfonate group, a phosphate group, a carboxy group, and a phenolic hydroxy group.

3. The film-forming composition according to claim 2, wherein the two or more acidic groups contain at least one selected from the group consisting of a sulfonate group, a phosphate group, a carboxy group, and a phenolic hydroxy group, and at least one selected from the group consisting of a carboxy group and a phenolic hydroxy group.

4. The film-forming composition according to claim 1, wherein the acidic compound contains an aromatic ring.

5. The film-forming composition according to claim 4, wherein at least one of the two or more acidic groups is directly bonded to the aromatic ring.

6. The film-forming composition according to claim 5, wherein all of the two or more acidic groups are directly bonded to the aromatic ring.

7. The film-forming composition according to claim 1, wherein the acidic compound contains an acidic compound containing two or three acidic groups.

8. The film-forming composition according to claim 1, wherein the two or more acidic groups are a sulfonate group and a phenolic hydroxy group; a sulfonate group and a carboxy group; a sulfonate group, a carboxy group, and a phenolic hydroxy group; a phosphate group and a phenolic hydroxy group; a phosphate group and a carboxy group; a phosphate group, a carboxy group, and a phenolic hydroxy group; or a carboxy group and a phenolic hydroxy group.

9. The film-forming composition according to claim 1, wherein the acidic compound contains an acidic compound of the following Formula (S):
(R.sup.A).sub.q—Ar—(R.sup.S).sub.r  (S) (wherein Ar is a C.sub.6-20 aromatic ring; R is an acidic group; R.sup.S is a substituent; q is the number of acidic groups bonded to the aromatic ring, and is an integer of 2 to 5; r is the number of substituents bonded to the aromatic ring, and is an integer of 0 to 3; q R.sup.As are mutually different groups; and r RSS are identical to or different from one another).

10. The film-forming composition according to claim 1, wherein the organic group containing an amino group is a group of the following Formula (A.sup.1): ##STR00055## (wherein R.sup.101 and R.sup.102 are each independently a hydrogen atom or a hydrocarbon group, and L is a substitutable alkylene group).

11. The film-forming composition according to claim 10, wherein the alkylene group is a linear or branched alkylene group having a carbon atom number of 1 to 10.

12. The film-forming composition according to claim 1, wherein the composition is for forming a resist underlayer film used in a lithographic process.

13. A resist underlayer film formed from the film-forming composition according to claim 1.

14. A method for producing a semiconductor device, the method comprising: a step of forming an organic underlayer film on a substrate; a step of forming, on the organic underlayer film, a resist underlayer film from the film-forming composition according to claim 1; and a step of forming a resist film on the resist underlayer film.

Description

EXAMPLES

[0281] The present invention will next be described in more detail with reference to Synthesis Examples and Examples, but the present invention should not be construed as being limited to the following Examples.

[0282] The weight average molecular weight of a polymer is determined by GPC analysis in terms of polystyrene. The GPC analysis was performed under the following conditions: GPC apparatus (trade name: HLC-8220GPC, available from Tosoh Corporation), GPC columns (trade name: Shodex KF803L, KF802, and KF801, available from Showa Denko K.K.), a column temperature of 40° C., tetrahydrofuran serving as an eluent (elution solvent), a flow amount (flow rate) of 1.0 mL/min, and polystyrene (available from Showa Denko K.K.) as a standard sample.

[0283] [1] Synthesis of Polymer (Hydrolysis Condensate)

Synthesis Example 1

[0284] A 300-mL flask was charged with 20.2 g of tetraethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], 11.3 g of methyltriethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], and 47.8 g of propylene glycol monoethyl ether, and then the mixture was stirred. While the resultant solution was stirred with a magnetic stirrer, a mixture of 20.4 g of aqueous p-phenolsulfonic acid solution (concentration: 0.2 mol/L) and 0.37 g of dimethylaminopropyltrimethoxysilane [available from Tokyo Chemical Industry Co., Ltd.] was added dropwise to the solution.

[0285] After completion of the dropwise addition, the flask was transferred to an oil bath set at 60° C., and the mixture was refluxed for 240 minutes. Thereafter, ethanol, methanol, and water were distilled off under reduced pressure, to thereby prepare a hydrolysis condensate (polymer) concentrate containing propylene glycol monoethyl ether as a solvent. The resultant concentrate was found to have a solid content concentration of more than 20% by mass in terms of solid residue content when heated at 140° C.

[0286] Subsequently, propylene glycol monoethyl ether was added to the resultant concentrate so as to achieve a concentration of 20% by mass in terms of solid residue content when heated at 140° C., to thereby produce a hydrolysis condensate (polymer) solution containing propylene glycol monoethyl ether as a solvent (solid content concentration: 20% by mass). The resultant polymer was found to have a structure of Formula (E1) and a weight average molecular weight (Mw) of 2,000 as determined by GPC in terms of polystyrene.

##STR00037##

Synthesis Example 2

[0287] A hydrolysis condensate (polymer) solution (solid content concentration: 20% by mass) was produced in the same manner as in Synthesis Example 1, except that 20.4 g of aqueous p-phenolsulfonic acid solution (concentration: 0.2 mol/L) was replaced with 20.4 g of aqueous 5-sulfosalicylic acid solution (concentration: 0.2 mol/L). The resultant polymer was found to have a structure of Formula (E2) and a weight average molecular weight (Mw) of 2,100 as determined by GPC in terms of polystyrene.

##STR00038##

Synthesis Example 3

[0288] A hydrolysis condensate (polymer) solution (solid content concentration: 20% by mass) was produced in the same manner as in Synthesis Example 1, except that 20.4 g of aqueous p-phenolsulfonic acid solution (concentration: 0.2 mol/L) was replaced with 20.4 g of aqueous 4-sulfo-o-phthalic acid solution (concentration: 0.2 mol/L). The resultant polymer was found to have a structure of Formula (E3) and a weight average molecular weight (Mw) of 2,200 as determined by GPC in terms of polystyrene.

##STR00039##

Synthesis Example 4

[0289] A hydrolysis condensate (polymer) solution (solid content concentration: 20% by mass) was produced in the same manner as in Synthesis Example 1, except that 20.4 g of aqueous p-phenolsulfonic acid solution (concentration: 0.2 mol/L) was replaced with 20.4 g of aqueous p-hydroxyphenylphosphonic acid solution (concentration: 0.2 mol/L). The resultant polymer was found to have a structure of Formula (E4) and a weight average molecular weight (Mw) of 2,500 as determined by GPC in terms of polystyrene.

##STR00040##

Synthesis Example 5

[0290] A hydrolysis condensate (polymer) solution (solid content concentration: 20% by mass) was produced in the same manner as in Synthesis Example 1, except that 20.4 g of aqueous p-phenolsulfonic acid solution (concentration: 0.2 mol/L) was replaced with 20.4 g of aqueous p-phosphonobenzoic acid solution (concentration: 0.2 mol/L). The resultant polymer was found to have a structure of Formula (E5) and a weight average molecular weight (Mw) of 2,400 as determined by GPC in terms of polystyrene.

##STR00041##

Synthesis Example 6

[0291] A hydrolysis condensate (polymer) solution (solid content concentration: 20% by mass) was produced in the same manner as in Synthesis Example 1, except that 20.4 g of aqueous p-phenolsulfonic acid solution (concentration: 0.2 mol/L) was replaced with 20.4 g of aqueous 4-hydroxybenzoic acid solution (concentration: 0.2 mol/L). The resultant polymer was found to have a structure of Formula (E6) and a weight average molecular weight (Mw) of 2,200 as determined by GPC in terms of polystyrene.

##STR00042##

Synthesis Example 7

[0292] A 300-mL flask was charged with 19.9 g of tetraethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], 9.65 g of methyltriethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], 2.04 g of bicyclo[2.2.1]hept-5-en-2-yltriethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], and 47.9 g of propylene glycol monoethyl ether, and then the mixture was stirred. While the resultant solution was stirred with a magnetic stirrer, a mixture of 20.0 g of aqueous 5-sulfosalicylic acid solution (concentration: 0.2 mol/L) and 0.36 g of dimethylaminopropyltrimethoxysilane [available from Tokyo Chemical Industry Co., Ltd.] was added dropwise to the solution.

[0293] After completion of the dropwise addition, the flask was transferred to an oil bath set at 60° C., and the mixture was refluxed for 240 minutes. Thereafter, ethanol, methanol, and water were distilled off under reduced pressure, to thereby prepare a hydrolysis condensate (polymer) concentrate containing propylene glycol monoethyl ether as a solvent. The resultant concentrate was found to have a solid content concentration of more than 20% by mass in terms of solid residue content when heated at 140° C.

[0294] Subsequently, propylene glycol monoethyl ether was added to the resultant concentrate so as to achieve a concentration of 20% by mass in terms of solid residue content when heated at 140° C., to thereby produce a hydrolysis condensate (polymer) solution containing propylene glycol monoethyl ether as a solvent (solid content concentration: 20% by mass). The resultant polymer was found to have a structure of Formula (E7) and a weight average molecular weight (Mw) of 2,200 as determined by GPC in terms of polystyrene.

##STR00043##

Synthesis Example 8

[0295] A 300-mL flask was charged with 19.3 g of tetraethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], 9.36 g of methyltriethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], 3.19 g of diallyl isocyanurate propyltriethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], and 48.3 g of propylene glycol monoethyl ether, and then the mixture was stirred. While the resultant solution was stirred with a magnetic stirrer, a mixture of 19.48 g of aqueous 5-sulfosalicylic acid solution (concentration: 0.2 mol/L) and 0.35 g of dimethylaminopropyltrimethoxysilane [available from Tokyo Chemical Industry Co., Ltd.] was added dropwise to the solution. After completion of the dropwise addition, the flask was transferred to an oil bath set at 60° C., and the mixture was refluxed for 240 minutes. Thereafter, ethanol, methanol, and water were distilled off under reduced pressure, to thereby prepare a hydrolysis condensate (polymer) concentrate containing propylene glycol monoethyl ether as a solvent. The resultant concentrate was found to have a solid content concentration of more than 20% by mass in terms of solid residue content when heated at 140° C.

[0296] Subsequently, propylene glycol monoethyl ether was added to the resultant concentrate so as to achieve a concentration of 20% by mass in terms of solid residue content when heated at 140° C., to thereby produce a hydrolysis condensate (polymer) solution containing propylene glycol monoethyl ether as a solvent (solid content concentration: 20% by mass). The resultant polymer was found to have a structure of Formula (E8) and a weight average molecular weight (Mw) of 2,000 as determined by GPC in terms of polystyrene.

##STR00044##

Synthesis Example 9

[0297] A 300-mL flask was charged with 19.9 g of tetraethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], 9.64 g of methyltriethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], 2.09 g of thiocyanatopropyltriethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], and 48.0 g of propylene glycol monoethyl ether, and then the mixture was stirred. While the resultant solution was stirred with a magnetic stirrer, a mixture of 20.0 g of aqueous 5-sulfosalicylic acid solution (concentration: 0.2 mol/L) and 0.36 g of dimethylaminopropyltrimethoxysilane [available from Tokyo Chemical Industry Co., Ltd.] was added dropwise to the solution.

[0298] After completion of the dropwise addition, the flask was transferred to an oil bath set at 60° C., and the mixture was refluxed for 240 minutes. Thereafter, ethanol, methanol, and water were distilled off under reduced pressure, to thereby prepare a hydrolysis condensate (polymer) concentrate containing propylene glycol monoethyl ether as a solvent. The resultant concentrate was found to have a solid content concentration of more than 20% by mass in terms of solid residue content when heated at 140° C.

[0299] Subsequently, propylene glycol monoethyl ether was added to the resultant concentrate so as to achieve a concentration of 20% by mass in terms of solid residue content when heated at 140° C., to thereby produce a hydrolysis condensate (polymer) solution containing propylene glycol monoethyl ether as a solvent (solid content concentration: 20% by mass). The resultant polymer was found to have a structure of Formula (E9) and a weight average molecular weight (Mw) of 1,900 as determined by GPC in terms of polystyrene.

##STR00045##

Synthesis Example 10

[0300] A 300-mL flask was charged with 19.6 g of tetraethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], 9.49 g of methyltriethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], 2.70 g of triethoxy((2-methoxy-4-(methoxymethyl)phenoxy)methyl)silane [available from Tokyo Chemical Industry Co., Ltd.], and 48.2 g of propylene glycol monoethyl ether, and then the mixture was stirred. While the resultant solution was stirred with a magnetic stirrer, a mixture of 20.0 g of aqueous 5-sulfosalicylic acid solution (concentration: 0.2 mol/L) and 0.36 g of dimethylaminopropyltrimethoxysilane [available from Tokyo Chemical Industry Co., Ltd.] was added dropwise to the solution.

[0301] After completion of the dropwise addition, the flask was transferred to an oil bath set at 60° C., and the mixture was refluxed for 240 minutes. Thereafter, ethanol, methanol, and water were distilled off under reduced pressure, to thereby prepare a hydrolysis condensate (polymer) concentrate containing propylene glycol monoethyl ether as a solvent. The resultant concentrate was found to have a solid content concentration of more than 20% by mass in terms of solid residue content when heated at 140° C.

[0302] Subsequently, propylene glycol monoethyl ether was added to the resultant concentrate so as to achieve a concentration of 20% by mass in terms of solid residue content when heated at 140° C., to thereby produce a hydrolysis condensate (polymer) solution containing propylene glycol monoethyl ether as a solvent (solid content concentration: 20% by mass). The resultant polymer was found to have a structure of Formula (E10) and a weight average molecular weight (Mw) of 2,700 as determined by GPC in terms of polystyrene.

##STR00046##

Synthesis Example 11

[0303] A 300-mL flask was charged with 23.3 g of tetraethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], 7.11 g of methyltriethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], 1.58 g of phenyltrimethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], and 47.9 g of propylene glycol monoethyl ether, and then the mixture was stirred. While the resultant solution was stirred with a magnetic stirrer, 20.1 g of aqueous nitric acid solution (concentration: 0.2 mol/L) was added dropwise to the solution.

[0304] After completion of the dropwise addition, the flask was transferred to an oil bath set at 60° C., and the mixture was refluxed for 240 minutes. Thereafter, ethanol, methanol, and water were distilled off under reduced pressure, to thereby prepare a hydrolysis condensate (polymer) concentrate containing propylene glycol monoethyl ether as a solvent. The resultant concentrate was found to have a solid content concentration of more than 20% by mass in terms of solid residue content when heated at 140° C.

[0305] Subsequently, a solution prepared by dissolving 0.36 g of N,N-dimethyl-3-(trimethoxysilyl)propan-1-amine and 0.27 g of p-phenolsulfonic acid in propylene glycol monoethyl ether was added to the resultant concentrate so as to achieve a concentration of 20% by mass in terms of solid residue content when heated at 140° C., to thereby produce a hydrolysis condensate (polymer) solution containing propylene glycol monoethyl ether as a solvent (solid content concentration: 20% by mass). The resultant polymer was found to have a structure of Formula (E11) and a weight average molecular weight (Mw) of 2,500 as determined by GPC in terms of polystyrene.

##STR00047##

Synthesis Example 12

[0306] A 300-mL flask was charged with 23.3 g of tetraethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], 7.11 g of methyltriethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], 1.58 g of phenyltrimethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], and 47.9 g of propylene glycol monoethyl ether, and then the mixture was stirred. While the resultant solution was stirred with a magnetic stirrer, 20.1 g of aqueous nitric acid solution (concentration: 0.2 mol/L) was added dropwise to the solution.

[0307] After completion of the dropwise addition, the flask was transferred to an oil bath set at 60° C., and the mixture was refluxed for 240 minutes. Thereafter, ethanol, methanol, and water were distilled off under reduced pressure, to thereby prepare a hydrolysis condensate (polymer) concentrate containing propylene glycol monoethyl ether as a solvent. The resultant concentrate was found to have a solid content concentration of more than 20% by mass in terms of solid residue content when heated at 140° C.

[0308] Subsequently, a solution prepared by dissolving 0.47 g of 1-(3-triethoxysilyl)propyl)-4,5-dihydro-1H-imidazole and 0.34 g of 5-sulfosalicylic acid in propylene glycol monoethyl ether was added to the resultant concentrate so as to achieve a concentration of 20% by mass in terms of solid residue content when heated at 140° C., to thereby produce a hydrolysis condensate (polymer) solution containing propylene glycol monoethyl ether as a solvent (solid content concentration: 20% by mass). The resultant polymer was found to have a structure of Formula (E12) and a weight average molecular weight (Mw) of 2,500 as determined by GPC in terms of polystyrene.

##STR00048##

Comparative Synthesis Example 1

[0309] A 300-mL flask was charged with 20.3 g of tetraethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], 11.6 g of triethoxymethylsilane [available from Tokyo Chemical Industry Co., Ltd.], and 47.7 g of propylene glycol monoethyl ether, and then the mixture was stirred. While the resultant solution was stirred with a magnetic stirrer, 20.4 g of aqueous nitric acid solution (concentration: 0.2 mol/L) was added dropwise to the mixed solution.

[0310] After completion of the dropwise addition, the flask was transferred to an oil bath set at 60° C., and the mixture was refluxed for 240 minutes. Thereafter, ethanol, methanol, and water were distilled off under reduced pressure, to thereby prepare a hydrolysis condensate (polymer) concentrate containing propylene glycol monoethyl ether as a solvent. The resultant concentrate was found to have a solid content concentration of more than 20% by mass in terms of solid residue content when heated at 140° C.

[0311] Subsequently, propylene glycol monoethyl ether was added to the resultant concentrate so as to achieve a concentration of 20% by mass in terms of solid residue content when heated at 140° C., to thereby produce a hydrolysis condensate (polymer) solution containing propylene glycol monoethyl ether as a solvent (solid content concentration: 20% by mass). The resultant polymer was found to have a structure of Formula (C1) and a weight average molecular weight (Mw) of 1,700 as determined by GPC in terms of polystyrene.

##STR00049##

Comparative Synthesis Example 2

[0312] A 300-mL flask was charged with 20.3 g of tetraethoxysilane [available from Tokyo Chemical Industry Co., Ltd.], 11.6 g of triethoxymethylsilane [available from Tokyo Chemical Industry Co., Ltd.], and 47.7 g of propylene glycol monoethyl ether, and then the mixture was stirred. While the resultant solution was stirred with a magnetic stirrer, 20.4 g of aqueous methanesulfonic acid solution (0.2 mol/L) was added dropwise to the mixed solution.

[0313] After completion of the dropwise addition, the flask was transferred to an oil bath set at 60° C., and the mixture was refluxed for 240 minutes. Thereafter, ethanol, methanol, and water were distilled off under reduced pressure, to thereby prepare a hydrolysis condensate (polymer) concentrate containing propylene glycol monoethyl ether as a solvent. The resultant concentrate was found to have a solid content concentration of more than 20% by mass in terms of solid residue content when heated at 140° C.

[0314] Subsequently, propylene glycol monoethyl ether was added to the resultant concentrate so as to achieve a concentration of 20% by mass in terms of solid residue content when heated at 140° C., to thereby produce a hydrolysis condensate (polymer) solution containing propylene glycol monoethyl ether as a solvent (solid content concentration: 20% by mass). The resultant polymer was found to have a structure of Formula (C2) and a weight average molecular weight (Mw) of 1,900 as determined by GPC in terms of polystyrene.

##STR00050##

Comparative Synthesis Example 3

[0315] A hydrolysis condensate (polymer) solution (solid content concentration: 20% by mass) was produced in the same manner as in Synthesis Example 1, except that 20.4 g of aqueous p-phenolsulfonic acid solution (concentration: 0.2 mol/L) was replaced with 20.4 g of aqueous benzoic acid solution (concentration: 0.2 mol/L). The resultant polymer was found to have a structure of Formula (C3) and a weight average molecular weight (Mw) of 2,400 as determined by GPC in terms of polystyrene.

##STR00051##

Comparative Synthesis Example 4

[0316] A hydrolysis condensate (polymer) solution (solid content concentration: 20% by mass) was produced in the same manner as in Synthesis Example 1, except that 20.4 g of aqueous p-phenolsulfonic acid solution (concentration: 0.2 mol/L) was replaced with 20.4 g of aqueous benzenesulfonic acid solution (concentration: 0.2 mol/L). The resultant polymer was found to have a structure of Formula (C4) and a weight average molecular weight (Mw) of 2,800 as determined by GPC in terms of polystyrene.

##STR00052##

Comparative Synthesis Example 5

[0317] A hydrolysis condensate (polymer) solution (solid content concentration: 20% by mass) was produced in the same manner as in Synthesis Example 1, except that 20.4 g of aqueous p-phenolsulfonic acid solution (concentration: 0.2 mol/L) was replaced with 20.4 g of aqueous phenol solution (concentration: 0.2 mol/L). The resultant polymer was found to have a structure of Formula (C5) and a weight average molecular weight Mw of 700 as determined by GPC in terms of polystyrene.

##STR00053##

[0318] [2] Preparation of Film-Forming Composition

[0319] Each of the polysiloxanes (polymers) produced in the aforementioned Synthesis Examples, an acid (additive 1), a photoacid generator (additive 2), and a solvent were mixed in proportions shown in Table 1, and the resultant mixture was filtered with a fluororesin-made filter (0.1 μm), to thereby prepare a film-forming composition. In Table 1, the amount of each component added is shown by part(s) by mass.

[0320] The amount of each polymer shown in Table 1 corresponds not to the amount of the polymer solution, but to the amount of the polymer itself.

[0321] In Table 1, DIW denotes ultrapure water; PGEE, propylene glycol monoethyl ether; PGMEA, propylene glycol monoethyl ether acetate; and PGME, propylene glycol monoethyl ether.

[0322] Furthermore, MA denotes maleic acid; and TPSNO3, triphenylsulfonium nitrate.

TABLE-US-00001 TABLE 1 Polymer Additive 1 Additive 2 Solvent Example 1 Synthesis MA PGEE PGMEA PGME DIW Example 1 (part(s) by mass) 1 0.03 40 10 38 12 Example 2 Synthesis MA PGEE PGMEA PGME DIW Example 2 (part(s) by mass) 1 0.03 40 10 38 12 Example 3 Synthesis MA PGEE PGMEA PGME DIW Example 3 (part(s) by mass) 1 0.03 40 10 38 12 Example 4 Synthesis MA PGEE PGMEA PGME DIW Example 4 (part(s) by mass) 1 0.03 40 10 38 12 Example 5 Synthesis MA PGEE PGMEA PGME DIW Example 5 (part(s) by mass) 1 0.03 40 10 38 12 Example 6 Synthesis MA PGEE PGMEA PGME DIW Example 6 (part(s) by mass) 1 0.03 40 10 38 12 Example 7 Synthesis MA PGEE PGMEA PGME DIW Example 7 (part(s) by mass) 1 0.03 40 10 38 12 Example 8 Synthesis MA PGEE PGMEA PGME DIW Example 8 (part(s) by mass) 1 0.03 40 10 38 12 Example 9 Synthesis MA PGEE PGMEA PGME DIW Example 9 (part(s) by mass) 1 0.03 40 10 38 12 Example 10 Synthesis MA PGEE PGMEA PGME DIW Example 10 (part(s) by mass) 1 0.03 40 10 38 12 Example 11 Synthesis MA TPSNO3 PGEE PGMEA PGME DIW Example 11 (part(s) by mass) 1 0.03 0.03 40 10 38 12 Example 12 Synthesis MA TPSNO3 PGEE PGMEA PGME DIW Example 12 (part(s) by mass) 1 0.03 0.03 40 10 38 12 Comparative Comparative MA PGEE PGMEA PGME DIW Example 1 Synthesis Example 1 (part(s) by mass) 1 0.03 40 10 38 12 Comparative Comparative MA TPSNO3 PGEE PGMEA PGME DIW Example 2 Synthesis Example 2 (part(s) by mass) 1 0.03 0.05 40 10 38 12 Comparative Comparative MA TPSNO3 PGEE PGMEA PGME DIW Example 3 Synthesis Example 3 (part(s) by mass) 1 0.03 0.05 40 10 38 12 Comparative Comparative MA TPSNO3 PGEE PGMEA PGME DIW Example 4 Synthesis Example 4 (part(s) by mass) 1 0.03 0.05 40 10 38 12 Comparative Comparative MA TPSNO3 PGEE PGMEA PGME DIW Example 5 Synthesis Example 5 (part(s) by mass) 1 0.03 0.05 40 10 38 12

[0323] [3] Preparation of Organic Underlayer Film-Forming Composition

[0324] In a nitrogen atmosphere, a 100-mL four-necked flask was charged with 6.69 g (0.040 mol) of carbazole (available from Tokyo Chemical Industry Co., Ltd.), 7.28 g (0.040 mol) of 9-fluorenone (available from Tokyo Chemical Industry Co., Ltd.), and 0.76 g (0.0040 mol) of p-toluenesulfonic acid monohydrate (available from Tokyo Chemical Industry Co., Ltd.), and then 6.69 g of 1,4-dioxane (available from KANTO CHEMICAL CO., INC.) was added to the flask. The resultant mixture was stirred and heated to 100° C. for dissolution, to thereby initiate polymerization. After the elapse of 24 hours, the reaction mixture was left to cool to 60° C.

[0325] The cooled reaction mixture was then diluted with 34 g of chloroform (available from KANTO CHEMICAL CO., INC.), and the diluted mixture was added to 168 g of methanol (available from KANTO CHEMICAL CO., INC.) for precipitation.

[0326] The resultant precipitate was filtered, and the filtrate was dried with a reduced-pressure dryer at 80° C. for 24 hours, to thereby yield 9.37 g of a target polymer of Formula (3-1) (hereinafter abbreviated as “PCzFL”).

[0327] The results of .sup.1H-NMR analysis of PCzFL were as follows: .sup.1H-NMR (400 MHz, DMSO-d.sub.6): δ7.03-7.55 (br, 12H), 67.61-8.10 (br, 4H), δ11.18 (br, 1H).

[0328] PCzFL was found to have a weight average molecular weight Mw of 2,800 as determined by GPC in terms of polystyrene and a polydispersity Mw/Mn of 1.77.

##STR00054##

[0329] Subsequently, 20 g of PCzFL was mixed with 3.0 g of tetramethoxymethyl glycoluril (trade name: Powderlink 1174, available from Cytec Industries Japan (former Mitsui Cytec Ltd.)) serving as a crosslinking agent, 0.30 g of pyridinium p-toluenesulfonate serving as a catalyst, and 0.06 g of MEGAFAC R-30 (trade name, available from DIC Corporation) serving as a surfactant, and the mixture was dissolved in 88 g of propylene glycol monomethyl ether acetate. Thereafter, the resultant solution was filtered with a polyethylene-made microfilter (pore size: 0.10 μm), and then filtered with a polyethylene-made microfilter (pore size: 0.05 μm), to thereby prepare an organic underlayer film-forming composition used for a lithographic process using a multilayer film.

[0330] [4] Tests for Solvent Resistance and Resistance to Dissolution in Developer

[0331] Each of the film-forming compositions prepared in Examples 1 to 12 and Comparative Examples 1 and 5 was applied onto a silicon wafer with a spinner, and then heated on a hot plate at 215° C. for one minute, to thereby form an Si-containing film. The thickness of the resultant Si-containing film was measured.

[0332] Subsequently, a mixed solvent of propylene glycol monomethyl ether/propylene glycol monomethyl ether acetate (7/3 (V/V)) was applied onto the Si-containing film, and then spin-dried. The thickness of the dried Si-containing film was measured, to thereby evaluate a change in film thickness between before and after application of the mixed solvent. Solvent resistance was evaluated as “Good” or “Not cured” when a change in film thickness after application of the mixed solvent was less than 1% or 1% or more, respectively, on the basis of the thickness before application of the mixed solvent.

[0333] Separately, an alkaline developer (2.38% aqueous TMAH solution) was applied onto an Si-containing film formed on a silicon wafer in the same manner as described above, and then spin-dried. The thickness of the dried underlayer film was measured, to thereby evaluate a change in film thickness between before and after application of the developer. Developer resistance was evaluated as “Good” or “Not cured” when a change in film thickness was less than 1% or 1% or more, respectively, on the basis of the thickness before application of the developer.

[0334] The results are shown in Table 2.

TABLE-US-00002 TABLE 2 Film-forming composition Solvent resistance Developer resistance Example 1 Good Good Example 2 Good Good Example 3 Good Good Example 4 Good Good Example 5 Good Good Example 6 Good Good Example 7 Good Good Example 8 Good Good Example 9 Good Good Example 10 Good Good Example 11 Good Good Example 12 Good Good Comparative Example 1 Not cured Not cured Comparative Example 5 Good Not cured

[0335] As shown in Table 2, a film formed from the film-forming composition of the present invention exhibited good resistance to a solvent and a developer.

[0336] [5] Measurement of Dry Etching Rate

[0337] The following etchers and etching gases were used for measurement of dry etching rate.

[0338] Lam2300 (available from Lam Research Co., Ltd.): CF.sub.4/CHF.sub.3/N.sub.2 (fluorine-containing gas)

[0339] RIE-10NR (available from SAMCO Inc.): O.sub.2 (oxygen-containing gas)

[0340] Each of the film-forming compositions prepared in Examples 1 to 12 was applied onto a silicon wafer with a spinner, and then heated on a hot plate at 215° C. for one minute, to thereby form an Si-containing film (thickness: 0.02 μm).

[0341] Similarly, the aforementioned organic underlayer film-forming composition was applied onto a silicon wafer with a spinner, and then heated on a hot plate at 215° C. for one minute, to thereby form an organic underlayer film (thickness: 0.20 μm).

[0342] The resultant silicon wafer provided with the Si-containing film was used for measurement of dry etching rate with CF.sub.4/CHF.sub.3/N.sub.2 gas and O.sub.2 gas as etching gases. Also, the silicon wafer provided with the organic underlayer film was used for measurement of dry etching rate with O.sub.2 gas as an etching gas. The results are shown in Table 3.

[0343] The dry etching rate of the Si-containing film with O.sub.2 gas was expressed as the ratio (resistance) relative to the dry etching rate of the organic underlayer film.

TABLE-US-00003 TABLE 3 Oxygen-containing Etching rate with gas resistance (ratio fluorine-containing relative to organic Film-forming composition gas (nm/min) underlayer film) Example 1 38 0.02 Example 2 42 0.02 Example 3 38 0.02 Example 4 40 0.03 Example 5 38 0.02 Example 6 37 0.02 Example 7 36 0.02 Example 8 42 0.04 Example 9 44 0.02 Example 10 36 0.03 Example 11 36 0.02 Example 12 34 0.02

[0344] As shown in Table 3, a film formed from the film-forming composition of the present invention exhibited a high etching rate with respect to a fluorine-containing gas, and better resistance to an oxygen-containing gas than an organic underlayer film.

[0345] [6] Measurement of Wet Etching Rate

[0346] Each of the film-forming compositions prepared in Examples 1 to 12 and Comparative Examples 2 and 4 was applied onto a silicon wafer with a spinner, and then heated on a hot plate at 215° C. for one minute, to thereby form an Si-containing film (thickness: 0.02 μm).

[0347] The resultant silicon wafer provided with the Si-containing film was used for measurement of wet etching rate with an aqueous NH.sub.3/HF mixed solution as a wet etching agent. When the wet etching rate was 10 nm/min or more, evaluation “Good” was given, whereas when the wet etching rate was less than 10 nm/min, evaluation “Poor” was given. The results are shown in Table 4.

TABLE-US-00004 TABLE 4 Aqueous NH.sub.3/HF solution Film-forming composition Wet etching rate Example 1 Good Example 2 Good Example 3 Good Example 4 Good Example 5 Good Example 6 Good Example 7 Good Example 8 Good Example 9 Good Example 10 Good Example 11 Good Example 12 Good Comparative Example 2 Poor Comparative Example 4 Poor

[0348] As shown in Table 4, a film formed from the film-forming composition of the present invention exhibited a high wet etching rate with respect to a wet etching agent.

[0349] [7] Formation of Resist Pattern by EUV Exposure: Negative Solvent Development

[0350] The aforementioned organic underlayer film-forming composition was applied onto a silicon wafer by spin coating, and then heated on a hot plate at 215° C. for one minute, to thereby form an organic underlayer film (layer A) (thickness: 90 nm).

[0351] The film-forming composition prepared in Example 1 was applied onto the organic underlayer film by spin coating, and then heated on a hot plate at 215° C. for one minute, to thereby form a resist underlayer film (layer B) (thickness: 20 nm).

[0352] An EUV resist solution (methacrylate resin-based resist) was applied onto the resist underlayer film by spin coating, and then heated on a hot plate at 130° C. for one minute, to thereby form an EUV resist film (layer C). Thereafter, the EUV resist film was exposed to light with an EUV exposure apparatus (NXE3300B, available from ASML) under the following conditions: NA: 0.33, σ: 0.67/0.90, Dipole.

[0353] After the light exposure, post exposure bake (at 110° C. for one minute) was performed, and the resultant product was cooled on a cooling plate to room temperature, followed by development with an organic solvent developer (butyl acetate) for one minute and subsequent rinsing treatment, to thereby form a resist pattern.

[0354] Each of the compositions prepared in Examples 2 to 12 and Comparative Examples 3 and 5 was used, and a resist pattern was formed through the same procedure as described above.

[0355] Each of the thus-formed resist patterns was evaluated for formation of a 44 nm pitch and a 22 nm line-and-space by determining the pattern shape through observation of a cross section of the pattern.

[0356] In the observation of the pattern shape, evaluation “Good” was given to a shape between footing and undercut and a state of no significant residue in a space portion; evaluation “Collapse” was given to an unfavorable state of peeling and collapse of the resist pattern; and evaluation “Bridge” was given to an unfavorable state of contact between upper portions or lower portions of the resist pattern. The results are shown in Table 5.

TABLE-US-00005 TABLE 5 Film-forming composition Evaluation result Example 1 Good Example 2 Good Example 3 Good Example 4 Good Example 5 Good Example 6 Good Example 7 Good Example 8 Good Example 9 Good Example 10 Good Example 11 Good Example 12 Good Comparative Example 3 Collapse Comparative Example 5 Collapse

[0357] As shown in Table 5, a film formed from the film-forming composition of the present invention effectively functioned as a resist underlayer film, and achieved excellent lithographic property.

[0358] [8] Formation of Resist Pattern by EUV Exposure: Positive Alkali Development

[0359] The aforementioned organic underlayer film-forming composition was applied onto a silicon wafer by spin coating, and then heated on a hot plate at 215° C. for one minute, to thereby form an organic underlayer film (layer A) (thickness: 90 nm).

[0360] The film-forming composition prepared in Example 11 was applied onto the organic underlayer film by spin coating, and then heated on a hot plate at 215° C. for one minute, to thereby form a resist underlayer film (layer B) (thickness: 20 nm).

[0361] An EUV resist solution (methacrylate resin-based resist) was applied onto the resist underlayer film by spin coating, and then heated on a hot plate at 130° C. for one minute, to thereby form an EUV resist film (layer C). Thereafter, the EUV resist film was exposed to light with an EUV exposure apparatus (NXE3300B, available from ASML) under the following conditions: NA: 0.33, σ: 0.67/0.90, Dipole.

[0362] After the light exposure, post exposure bake (at 110° C. for one minute) was performed, and the resultant product was cooled on a cooling plate to room temperature, followed by development with an alkaline developer (aqueous TMAH solution) for one minute and subsequent rinsing treatment, to thereby form a resist pattern.

[0363] Each of the compositions prepared in Example 12 and Comparative Example 4 was used, and a resist pattern was formed through the same procedure as described above.

[0364] Each of the thus-formed resist patterns was evaluated for formation of a 44 nm pitch and a 22 nm line-and-space by determining the pattern shape through observation of a cross section of the pattern.

[0365] In the observation of the pattern shape, evaluation “Good” was given to a shape between footing and undercut and a state of no significant residue in a space portion; evaluation “Collapse” was given to an unfavorable state of peeling and collapse of the resist pattern; and evaluation “Bridge” was given to an unfavorable state of contact between upper portions or lower portions of the resist pattern. The results are shown in Table 6.

TABLE-US-00006 TABLE 6 Film-forming composition Evaluation result Example 11 Good Example 12 Good Comparative Example 4 Collapse

[0366] As shown in Table 6, a film formed from the film-forming composition of the present invention effectively functioned as a resist underlayer film, and achieved excellent lithographic property.