SILICON-CONTAINING RESIST UNDERLAYER FILM-FORMING COMPOSITION INCLUDING ORGANIC GROUP HAVING AMMONIUM GROUP

Abstract

A composition for forming a resist underlayer film containing a hydrolysis condensate prepared through hydrolysis and condensation of a hydrolyzable silane, wherein the hydrolyzable silane contains a hydrolyzable silane of Formula (1):

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

wherein R.sup.1 is an organic group having a primary amino group, a secondary amino group, or a tertiary amino group and is bonded to a silicon atom via an Si—C bond; R.sup.2 is an alkyl group, an aryl group, a halogenated alkyl group, a halogenated aryl group, an alkoxyaryl group, an alkenyl group, an acyloxyalkyl group, or an organic group having an acryloyl group, a methacryloyl group, a mercapto group, an amino group, an amide group, a hydroxyl group, an alkoxy group, an ester group, a sulfonyl group, or a cyano group, or any combination of these groups, and is bonded to a silicon atom via an Si—C bond; R.sup.1 and R.sup.2 are optionally bonded together to form a ring structure; R.sup.3 is an alkoxy group, an acyloxy group, or a halogen group; a is an integer of 1; b is an integer of 0 to 2; and a+b is an integer of 1 to 3; and the hydrolysis condensate contains an organic group having a salt structure formed between a counter anion derived from a nitric acid and a counter cation derived from a primary ammonium group, a secondary ammonium group, or a tertiary ammonium group.

Claims

1. A composition for forming a resist underlayer film containing a hydrolysis condensate prepared through hydrolysis and condensation of a hydrolyzable silane, wherein the hydrolyzable silane contains a hydrolyzable silane of Formula (1):
R.sup.1.sub.aR.sup.2.sub.bSi(R.sup.3).sub.4−(a+b)   Formula (1) wherein R.sup.1 is an organic group having a primary amino group, a secondary amino group, or a tertiary amino group and is bonded to a silicon atom via an Si—C bond; R.sup.2 is an alkyl group, an aryl group, a halogenated alkyl group, a halogenated aryl group, an alkoxyaryl group, an alkenyl group, an acyloxyalkyl group, or an organic group having an acryloyl group, a methacryloyl group, a mercapto group, an amino group, an amide group, a hydroxyl group, an alkoxy group, an ester group, a sulfonyl group, or a cyano group, or any combination of these groups, and is bonded to a silicon atom via an Si—C bond; R.sup.1 and R.sup.2 are optionally bonded together to form a ring structure; R.sup.3 is an alkoxy group, an acyloxy group, or a halogen group; a is an integer of 1; b is an integer of 0 to 2; and a+b is an integer of 1 to 3; and wherein the hydrolysis condensate contains an organic group having a salt structure formed between a counter anion derived from a nitric acid and a counter cation derived from a primary ammonium group, a secondary ammonium group, or a tertiary ammonium group.

2. The composition for resist underlayer film formation according to claim 1, wherein the hydrolysis condensate is a hydrolysis condensate prepared through hydrolysis and condensation of the hydrolyzable silane in a non-alcoholic solvent in the presence of the nitric acid.

3. The composition for forming a resist underlayer film according to claim 1, wherein the hydrolyzable silane of Formula (1) is selected from the group consisting of: ##STR00064## ##STR00065## ##STR00066## ##STR00067## ##STR00068## ##STR00069## ##STR00070## ##STR00071## wherein T represents an alkoxy group, an acyloxy group, or a halogen group.

4. The composition for forming a resist underlayer film according to claim 1, wherein the composition further comprises a hydrolysis product of the hydrolyzable silane of Formula (1).

5. The composition for forming a resist underlayer film according to claim 2, wherein the non-alcoholic solvent is a ketone or an ether.

6. The composition for forming a resist underlayer film according to claim 1, wherein the hydrolyzable silane comprises the hydrolyzable silane of Formula (1) and at least one additional hydrolyzable silane selected from the group consisting of a hydrolyzable silane of Formula (2):
R.sup.4.sub.cSi(R.sup.5).sub.4−c   Formula (2) wherein R.sup.4 is an alkyl group, an aryl group, a halogenated alkyl group, a halogenated aryl group, an alkoxyaryl group, an alkenyl group, an acyloxyalkyl group, or an organic group having an acryloyl group, a methacryloyl group, a mercapto group, an amino group, an amide group, a hydroxyl group, an alkoxy group, an ester group, a sulfonyl group, or a cyano group, or any combination of these groups, and is bonded to a silicon atom via an Si—C bond; R.sup.5 is an alkoxy group, an acyloxy group, or a halogen group; and c is an integer of 0 to 3) and a hydrolyzable silane of Formula (3):
R.sup.6.sub.dSi(R.sup.7).sub.3−d.sub.2Y.sub.e   Formula (3) wherein R.sup.6 is an alkyl group and is bonded to a silicon atom via an Si—C bond; R.sup.7 is an alkoxy group, an acyloxy group, or a halogen group; Y is an alkylene group or an arylene group; d is an integer of 0 or 1; and e is an integer of 0 or 1.

7. The composition for forming a resist underlayer film according to claim 6, wherein the amount of the hydrolyzable silane of Formula (1) contained in the entire hydrolyzable silane is 0.1% by mole to 100% by mole relative to the total amount by mole of the entire hydrolyzable silane.

8. The composition for forming a resist underlayer film according to claim 1, wherein the composition further comprises a crosslinkable compound.

9. The composition for forming a resist underlayer film according to claim 1, wherein the composition further comprises an acid or an acid generator.

10. The composition for forming a resist underlayer film according to claim 1, wherein the composition further comprises water.

11. A resist underlayer film which is a cured product of the composition for forming a silicon-containing resist underlayer film according to claim 1.

12. A semiconductor processing substrate comprising a semiconductor substrate and the resist underlayer film according to claim 11 thereon.

13. A method for manufacturing a semiconductor device, comprising a step of forming an organic underlayer film on a substrate, and a step of forming the resist underlayer film according to claim 11 on the organic underlayer film, and a step of forming a resist film on the resist underlayer film.

14. The method for manufacturing a semiconductor device according to claim 13, further comprising a step of removing the resist underlayer film with a chemical after the step of forming the resist film.

15. The method for manufacturing a semiconductor device according to claim 14, wherein the chemical is sulfuric acid superwater (SPM) in which hydrogen peroxide solution and sulfuric acid are mixed, and/or ammonia superwater (SC1) in which hydrogen peroxide solution and ammonia water are mixed.

Description

EXAMPLES

Synthesis Example 1

[0159] A 300-ml flask was charged with 22.3 g of tetraethoxysilane, 6.5 g of methyltriethoxysilane, 3.2 g of triethoxysilylpropyldiallyl isocyanurate, and 48.5 g of acetone. While the mixture was stirred with a magnetic stirrer, a mixture of 19.2 g of 0.2 M aqueous nitric acid solution and 0.32 g of dimethylaminopropyltrimethoxysilane was added dropwise to the flask. After completion of the dropwise addition, the flask was transferred to an oil bath set at 85° C., and the mixture was refluxed for 240 minutes. Thereafter, 64 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol, ethanol, and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer). Subsequently, propylene glycol monomethyl ether was added to the aqueous solution so as to achieve a solid residue content of 13% by weight at 140° C. while a solvent proportion of propylene glycol monomethyl ether was 100%. The resultant polymer corresponds to Formula (A-1). The polymer was found to have a weight average molecular weight Mw of 1,500 as determined by GPC in terms of polystyrene.

Synthesis Example 2

[0160] A 300-ml flask was charged with 23.1 g of tetraethoxysilane, 6.8 g of methyltriethoxysilane, 1.9 g of glycidoxypropyltrimethoxysilane, and 48.1 g of acetone. While the mixture was stirred with a magnetic stirrer, a mixture of 19.8 g of 0.2 M aqueous nitric acid solution and 0.32 g of dimethylaminopropyltrimethoxysilane was added dropwise to the flask. After completion of the dropwise addition, the flask was transferred to an oil bath set at 85° C., and the mixture was refluxed for 240 minutes. Thereafter, 64 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol, ethanol, and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer). Subsequently, propylene glycol monomethyl ether was added to the aqueous solution so as to achieve a solid residue content of 13% by weight at 140° C. while a solvent proportion of propylene glycol monomethyl ether was 100%. The resultant polymer corresponds to Formula (A-2). The polymer was found to have a weight average molecular weight Mw of 2,000 as determined by GPC in terms of polystyrene.

Synthesis Example 3

[0161] A 300-ml flask was charged with 22.6 g of tetraethoxysilane, 6.6 g of methyltriethoxysilane, 2.7 g of phenylsulfonylpropyltriethoxysilane, and 48.4 g of acetone. While the mixture was stirred with a magnetic stirrer, a mixture of 19.4 g of 0.2 M aqueous nitric acid solution and 0.32 g of dimethylaminopropyltrimethoxysilane was added dropwise to the flask. After completion of the dropwise addition, the flask was transferred to an oil bath set at 85° C., and the mixture was refluxed for 240 minutes. Thereafter, 64 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol, ethanol, and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer). Subsequently, propylene glycol monomethyl ether was added to the aqueous solution so as to achieve a solid residue content of 13% by weight at 140° C. while a solvent proportion of propylene glycol monomethyl ether was100%. The resultant polymer corresponds to Formula (A-3). The polymer was found to have a weight average molecular weight Mw of 1,800 as determined by GPC in terms of polystyrene.

Synthesis Example 4

[0162] A 300-ml flask was charged with 23.0 g of tetraethoxysilane, 6.8 g of methyltriethoxysilane, 2.0 g of bicyclo(2,2,1)hept-5-en-yltriethoxysilane, and 48.2 g of acetone. While the mixture was stirred with a magnetic stirrer, a mixture of 19.7 g of 0.2 M aqueous nitric acid solution and 0.33 g of dimethylaminopropyltrimethoxysilane was added dropwise to the flask. After completion of the dropwise addition, the flask was transferred to an oil bath set at 85° C., and the mixture was refluxed for 240 minutes. Thereafter, 64 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol, ethanol, and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer). Subsequently, propylene glycol monomethyl ether was added to the aqueous solution so as to achieve a solid residue content of 13% by weight at 140° C. while a solvent proportion of propylene glycol monomethyl ether was 100%. The resultant polymer corresponds to Formula (A-4). The polymer was found to have a weight average molecular weight Mw of 2,000 as determined by GPC in terms of polystyrene.

Synthesis Example 5

[0163] A 300-ml flask was charged with 23.1 g of tetraethoxysilane, 6.8 g of methyltriethoxysilane, 1.9 g of cyclohexylepoxyethyltrimethoxysilane, and 48.1 g of acetone. While the mixture was stirred with a magnetic stirrer, a mixture of 19.8 g of 0.2 M aqueous nitric acid solution and 0.33 g of dimethylaminopropyltrimethoxysilane was added dropwise to the flask. After completion of the dropwise addition, the flask was transferred to an oil bath set at 85° C., and the mixture was refluxed for 240 minutes. Thereafter, 64 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol, ethanol, and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer). Subsequently, propylene glycol monomethyl ether was added to the aqueous solution so as to achieve a solid residue content of 13% by weight at 140° C. while a solvent proportion of propylene glycol monomethyl ether was100%. The resultant polymer corresponds to Formula (A-5). The polymer was found to have a weight average molecular weight Mw of 2,000 as determined by GPC in terms of polystyrene.

Synthesis Example 6

[0164] A 300-ml flask was charged with 22.7 g of tetraethoxysilane, 6.7 g of methyltriethoxysilane, 2.5 g of phenylsulfonamidopropyltrimethoxysilane, and 48.1 g of acetone. While the mixture was stirred with a magnetic stirrer, a mixture of 19.5 g of 0.2 M aqueous nitric acid solution and 0.32 g of dimethylaminopropyltrimethoxysilane was added dropwise to the flask. After completion of the dropwise addition, the flask was transferred to an oil bath set at 85° C., and the mixture was refluxed for 240 minutes. Thereafter, 64 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol, ethanol, and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer). Subsequently, propylene glycol monomethyl ether was added to the aqueous solution so as to achieve a solid residue content of 13% by weight at 140° C. while a solvent proportion of propylene glycol monomethyl ether was100%. The resultant polymer corresponds to Formula (A-6). The polymer was found to have a weight average molecular weight Mw of 2,000 as determined by GPC in terms of polystyrene.

Synthesis Example 7

[0165] A 300-ml flask was charged with 23.2 g of tetraethoxysilane, 6.8 g of methyltriethoxysilane, 1.6 g of cyclohexyltrimethoxysilane, and 48.0 g of acetone. While the mixture was stirred with a magnetic stirrer, a mixture of 19.9 g of 0.2 M aqueous nitric acid solution and 0.33 g of dimethylaminopropyltrimethoxysilane was added dropwise to the flask. After completion of the dropwise addition, the flask was transferred to an oil bath set at 85° C., and the mixture was refluxed for 240 minutes.

[0166] Thereafter, 64 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol, ethanol, and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer). Subsequently, propylene glycol monomethyl ether was added to the aqueous solution so as to achieve a solid residue content of 13% by weight at 140° C. while a solvent proportion of propylene glycol monomethyl ether was100%. The resultant polymer corresponds to Formula (A-7). The polymer was found to have a weight average molecular weight Mw of 1,500 as determined by GPC in terms of polystyrene.

Synthesis Example 8

[0167] A 300-ml flask was charged with 23.4 g of tetraethoxysilane, 8.3 g of methyltriethoxysilane, and 48.0 g of acetone. While the mixture was stirred with a magnetic stirrer, a mixture of 20.0 g of 0.2 M aqueous nitric acid solution and 0.33 g of dimethylaminopropyltrimethoxysilane was added dropwise to the flask. After completion of the dropwise addition, the flask was transferred to an oil bath set at 85° C., and the mixture was refluxed for 240 minutes. Thereafter, 64 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol, ethanol, and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer). Subsequently, propylene glycol monomethyl ether was added to the aqueous solution so as to achieve a solid residue content of 13% by weight at 140° C. while a solvent proportion of propylene glycol monomethyl ether was100%. The resultant polymer corresponds to Formula (A-8). The polymer was found to have a weight average molecular weight Mw of 1,700 as determined by GPC in terms of polystyrene.

Synthesis Example 9

[0168] A 300-ml flask was charged with 22.9 g of tetraethoxysilane, 6.7 g of methyltriethoxysilane, 2.2 g of trifluoroacetamidopropyltriethoxysilane, and 48.2 g of acetone. While the mixture was stirred with a magnetic stirrer, a mixture of 19.6 g of 0.2 M aqueous nitric acid solution and 0.33 g of dimethylaminopropyltrimethoxysilane was added dropwise to the flask. After completion of the dropwise addition, the flask was transferred to an oil bath set at 85° C., and the mixture was refluxed for 240 minutes. Thereafter, 64 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol, ethanol, and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer). Subsequently, propylene glycol monomethyl ether was added to the aqueous solution so as to achieve a solid residue content of 13% by weight at 140° C. while a solvent proportion of propylene glycol monomethyl ether was 100%. The resultant polymer corresponds to Formula (A-9). The polymer was found to have a weight average molecular weight Mw of 1,800 as determined by GPC in terms of polystyrene.

Synthesis Example 10

[0169] A 300-ml flask was charged with 22.8 g of tetraethoxysilane, 6.7 g of methyltriethoxysilane, 2.4 g of succinic anhydride-propyltriethoxysilane, and 48.3 g of acetone. While the mixture was stirred with a magnetic stirrer, a mixture of 19.5 g of 0.2 M aqueous nitric acid solution and 0.32 g of dimethylaminopropyltrimethoxysilane was added dropwise to the flask. After completion of the dropwise addition, the flask was transferred to an oil bath set at 85° C., and the mixture was refluxed for 240 minutes. Thereafter, 64 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol, ethanol, and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer). Subsequently, propylene glycol monomethyl ether was added to the aqueous solution so as to achieve a solid residue content of 13% by weight at 140° C. while a solvent proportion of propylene glycol monomethyl ether was 100%. The resultant polymer corresponds to Formula (A-10). The polymer was found to have a weight average molecular weight Mw of 1,600 as determined by GPC in terms of polystyrene.

Synthesis Example 11

[0170] A 300-ml flask was charged with 22.9 g of tetraethoxysilane, 6.7 g of methyltriethoxysilane, 2.2 g of p-ethoxyethoxyphenyltrimethoxysilane, and 48.2 g of acetone. While the mixture was stirred with a magnetic stirrer, a mixture of 19.6 g of 0.2 M aqueous nitric acid solution and 0.33 g of dimethylaminopropyltrimethoxysilane was added dropwise to the flask. After completion of the dropwise addition, the flask was transferred to an oil bath set at 85° C., and the mixture was refluxed for 240 minutes. Thereafter, 64 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol, ethanol, and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer). Subsequently, propylene glycol monomethyl ether was added to the aqueous solution so as to achieve a solid residue content of 13% by weight at 140° C. while a solvent proportion of propylene glycol monomethyl ether was100%. The resultant polymer corresponds to Formula (A-11). The polymer was found to have a weight average molecular weight Mw of 1,600 as determined by GPC in terms of polystyrene.

Synthesis Example 12

[0171] A 300-ml flask was charged with 23.5 g of tetraethoxysilane, 6.9 g of methyltriethoxysilane, 1.2 g of vinyltrimethoxysilane, and 47.9 g of acetone. While the mixture was stirred with a magnetic stirrer, a mixture of 20.2 g of 0.2 M aqueous nitric acid solution and 0.33 g of dimethylaminopropyltrimethoxysilane was added dropwise to the flask. After completion of the dropwise addition, the flask was transferred to an oil bath set at 85° C., and the mixture was refluxed for 240 minutes. Thereafter, 64 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol, ethanol, and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer). Subsequently, propylene glycol monomethyl ether was added to the aqueous solution so as to achieve a solid residue content of 13% by weight at 140° C. while a solvent proportion of propylene glycol monomethyl ether was100%. The resultant polymer corresponds to Formula (A-12). The polymer was found to have a weight average molecular weight Mw of 2,000 as determined by GPC in terms of polystyrene.

Synthesis Example 13

[0172] A 300-ml flask was charged with 23.1 g of tetraethoxysilane, 5.7 g of methyltriethoxysilane, and 48.0 g of acetone. While the mixture was stirred with a magnetic stirrer, a mixture of 20.0 g of 2 M aqueous nitric acid solution and 3.3 g of dimethylaminopropyltrimethoxysilane was added dropwise to the flask. After completion of the dropwise addition, the flask was transferred to an oil bath set at 85° C., and the mixture was refluxed for 240 minutes. Thereafter, 64 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol, ethanol, and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer). Subsequently, propylene glycol monomethyl ether was added to the aqueous solution so as to achieve a solid residue content of 13% by weight at 140° C. while a solvent proportion of propylene glycol monomethyl ether was100%. The resultant polymer corresponds to Formula (A-8). The polymer was found to have a weight average molecular weight Mw of 2,800 as determined by GPC in terms of polystyrene.

Synthesis Example 14

[0173] A 300-ml flask was charged with 18.3 g of tetraethoxysilane, 15.1 g of triethoxysilylpropyldiallyl isocyanurate, and 50.6 g of acetone. While the mixture was stirred with a magnetic stirrer, a mixture of 15.7 g of 0.2 M aqueous nitric acid solution and 0.26 g of dimethylaminopropyltrimethoxysilane was added dropwise to the flask. After completion of the dropwise addition, the flask was transferred to an oil bath set at 85° C., and the mixture was refluxed for 240 minutes. Thereafter, 64 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol, ethanol, and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer). Subsequently, propylene glycol monomethyl ether was added to the aqueous solution so as to achieve a solid residue content of 13% by weight at 140° C. while a solvent proportion of propylene glycol monomethyl ether was100%. The resultant polymer corresponds to Formula (A-13). The polymer was found to have a weight average molecular weight Mw of 1,500 as determined by GPC in terms of polystyrene.

Synthesis Example 15

[0174] A 300-ml flask was charged with 22.3 g of tetraethoxysilane, 6.6 g of methyltriethoxysilane, 3.2 g of triethoxysilylpropyldiallyl isocyanurate, and 48.5 g of acetone. While the mixture was stirred with a magnetic stirrer, a mixture of 19.2 g of 0.2 M aqueous nitric acid solution and 0.27 g of aminopropyltrimethoxysilane was added dropwise to the flask. After completion of the dropwise addition, the flask was transferred to an oil bath set at 85° C., and the mixture was refluxed for 240 minutes. Thereafter, 64 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol, ethanol, and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer). Subsequently, propylene glycol monomethyl ether was added to the aqueous solution so as to achieve a solid residue content of 13% by weight at 140° C. while a solvent proportion of propylene glycol monomethyl ether was100%. The resultant polymer corresponds to Formula (A-14). The polymer was found to have a weight average molecular weight Mw of 2,500 as determined by GPC in terms of polystyrene.

Synthesis Example 16

[0175] A 300-ml flask was charged with 22.3 g of tetraethoxysilane, 6.5 g of methyltriethoxysilane, 3.2 g of triethoxysilylpropyldiallyl isocyanurate, and 48.6 g of acetone. While the mixture was stirred with a magnetic stirrer, a mixture of 19.1 g of 0.2 M aqueous nitric acid solution and 0.42 g of 4,5-dihydroxyimidazole propyltriethoxysilane was added dropwise to the flask. After completion of the dropwise addition, the flask was transferred to an oil bath set at 85° C., and the mixture was refluxed for 240 minutes. Thereafter, 64 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol, ethanol, and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer). Subsequently, propylene glycol monomethyl ether was added to the aqueous solution so as to achieve a solid residue content of 13% by weight at 140° C. while a solvent proportion of propylene glycol monomethyl ether was100%. The resultant polymer corresponds to Formula (A-15). The polymer was found to have a weight average molecular weight Mw of 2,000 as determined by GPC in terms of polystyrene.

Synthesis Example 17

[0176] A 300-ml flask was charged with 22.2 g of tetraethoxysilane, 6.5 g of methyltriethoxysilane, 3.2 g of triethoxysilylpropyldiallyl isocyanurate, and 48.6 g of acetone. While the mixture was stirred with a magnetic stirrer, a mixture of 19.1 g of 0.2 M aqueous nitric acid solution and 0.47 g of bishydroxyethylaminopropyltriethoxysilane was added dropwise to the flask. After completion of the dropwise addition, the flask was transferred to an oil bath set at 85° C., and the mixture was refluxed for 240 minutes. Thereafter, 64 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol, ethanol, and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer). Subsequently, propylene glycol monomethyl ether was added to the aqueous solution so as to achieve a solid residue content of 13% by weight at 140° C. while a solvent proportion of propylene glycol monomethyl ether was 100%. The resultant polymer corresponds to Formula (A-16). The polymer was found to have a weight average molecular weight Mw of 1,800 as determined by GPC in terms of polystyrene.

Synthesis Example 18

[0177] A 500-ml flask was charged with 91.16 g of water. While the mixture was stirred with a magnetic stirrer, 22.23 g of dimethylaminopropyltrimethoxysilane and 8.16 g of triethoxysilylpropylsuccinic anhydride were added dropwise to the mixture. After completion of the dropwise addition, the flask was transferred to an oil bath set at 40° C., and reaction was allowed to proceed for 240 minutes. Thereafter, the reaction mixture was cooled to room temperature, and 91.16 g of water was added to the reaction mixture. Methanol (i.e., a reaction by-product) and water were then distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polysiloxane). Subsequently, water was added to the aqueous solution so as to achieve a solid residue content of 20% by mass at 140° C. while a solvent proportion of water was 100% (solvent: water only). The resultant polymer corresponds to Formula (A-17). The polymer was found to have a weight average molecular weight Mw of 3,300 as determined by GPC in terms of polyethylene glycol.

Synthesis Example 19

[0178] A 500-ml flask was charged with 16.84 g of acetic acid, 70.11 of water, and 70.11 g of acetone. While the mixture was stirred with a magnetic stirrer, 23.26 g of dimethylaminopropyltrimethoxysilane was added dropwise to the mixture. Thereafter, the resultant mixture was added to 15.58 g of tetraethoxysilane. The flask was then transferred to an oil bath set at 110° C., and reaction was allowed to proceed for 240 minutes. Thereafter, the reaction mixture was cooled to room temperature, and 116.51 g of water was added to the reaction mixture. Ethanol (i.e., a reaction by-product) and water were then distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polysiloxane). Subsequently, water was added to the aqueous solution so as to achieve a solid residue content of 20% by mass at 140° C. while a solvent proportion of water was 100% (solvent: water only). The resultant polymer corresponds to Formula (A-18). The polymer was found to have a weight average molecular weight Mw of 1,000 as determined by GPC in terms of polyethylene glycol.

Synthesis Example 20

[0179] A 500-ml flask was charged with 25.24 g of 70% nitric acid, 70.11 g of water, and 70.11 g of acetone. While the mixture was stirred with a magnetic stirrer, 23.26 g of dimethylaminopropyltrimethoxysilane was added dropwise to the mixture. Thereafter, the resultant mixture was added to 15.58 g of tetraethoxysilane. The flask was then transferred to an oil bath set at 110° C., and reaction was allowed to proceed for 240 minutes. Thereafter, the reaction mixture was cooled to room temperature, and 143.87 g of water was added to the reaction mixture. Ethanol (i.e., a reaction by-product) and water were then distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polysiloxane). Subsequently, water was added to the aqueous solution so as to achieve a solid residue content of 20% by mass at 140° C. while a solvent proportion of water was 100% (solvent: water only). The resultant polymer corresponds to Formula (A-19). The polymer was found to have a weight average molecular weight Mw of 800 as determined by GPC in terms of polyethylene glycol.

Synthesis Example 21

[0180] A 500-ml flask was charged with 10.78 g of acetic acid, 44.90 g of water, and 44.90 g of acetone. While the mixture was stirred with a magnetic stirrer, 14.89 g of dimethylaminopropyltrimethoxysilane was added dropwise to the mixture. Thereafter, the resultant mixture was added to 34.92 g of tetraethoxysilane. The flask was then transferred to an oil bath set at 110° C., and reaction was allowed to proceed for 240 minutes. Thereafter, the reaction mixture was cooled to room temperature, and 149.43 g of water was added to the reaction mixture. Ethanol (i.e., a reaction by-product) and water were then distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polysiloxane). Subsequently, water was added to the aqueous solution so as to achieve a solid residue content of 20% by mass at 140° C. while a solvent proportion of water was 100% (solvent: water only). The resultant polymer corresponds to Formula (A-18). The polymer was found to have a weight average molecular weight Mw of 1,200 as determined by GPC in terms of polyethylene glycol.

Synthesis Example 22

[0181] A 500-ml flask was charged with 16.16 g of 70% nitric acid, 44.90 g of water, and 44.90 g of acetone. While the mixture was stirred with a magnetic stirrer, 14.89 g of dimethylaminopropyltrimethoxysilane was added dropwise to the mixture. Thereafter, the resultant mixture was added to 34.92 g of tetraethoxysilane. The flask was then transferred to an oil bath set at 110° C., and reaction was allowed to proceed for 240 minutes. Thereafter, the reaction mixture was cooled to room temperature, and 149.43 g of water was added to the reaction mixture. Ethanol (i.e., a reaction by-product) and water were then distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polysiloxane). Subsequently, water was added to the aqueous solution so as to achieve a solid residue content of 20% by mass at 140° C. while a solvent proportion of water was 100% (solvent: water only). The resultant polymer corresponds to Formula (A-19). The polymer was found to have a weight average molecular weight Mw of 1,000 as determined by GPC in terms of polyethylene glycol.

Comparative Synthesis Example 1

[0182] A 300-ml flask was charged with 24.1 g of tetraethoxysilane, 1.8 g of phenyltrimethoxysilane, 9.5 g of triethoxymethylsilane, and 53.0 g of acetone. While the mixture was stirred with a magnetic stirrer, 11.7 g of 0.01 M aqueous hydrochloric acid solution was added dropwise to the mixture. After completion of the dropwise addition, the flask was transferred to an oil bath set at 85° C., and the mixture was refluxed for 240 minutes. Thereafter, 70 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol, ethanol, and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer). Subsequently, propylene glycol monomethyl ether was added to the aqueous solution so as to achieve a solid residue content of 13% by weight at 140° C. The resultant polymer corresponds to the following Formula (E-1). The polymer was found to have a weight average molecular weight Mw of 1,400 as determined by GPC in terms of polystyrene.

##STR00062##

[0183] (Preparation of Resist Underlayer Film-Forming Composition)

[0184] Each of the polysiloxanes (polymers) prepared in the aforementioned Synthesis Examples, an acid, 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 resist underlayer film-forming composition. 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.

[0185] The water used in Examples was ultrapure water. In the following Tables, the amount of each component is represented by “parts by mass.” In the following Tables, MA denotes maleic acid; NfA, nonafluorobutanesulfonic acid;

[0186] APTEOS, aminopropyltrimethoxysilane; TPSCS, triphenylsulfonium camphorsulfonate; TPSNO3, triphenylsulfonium nitrate; PGMEA, propylene glycol monomethyl ether acetate; PGEE, propylene glycol monoethyl ether, PGME, propylene glycol monomethyl ether; and DIW, water.

TABLE-US-00001 TABLE 1 Si polymer solution Additive 1 Additive 2 Solvent Example 1 Synthesis MA PGEE PGMEA PGME DIW Example 1 (parts by mass) 1 0.03 40 10 38 12 Example 2 Synthesis MA PGEE PGMEA PGME DIW Example 2 (parts by mass) 1 0.03 40 10 38 12 Example 3 Synthesis MA PGEE PGMEA PGME DIW Example 3 (parts by mass) 1 0.03 40 10 38 12 Example 4 Synthesis MA PGEE PGMEA PGME DIW Example 4 (parts by mass) 1 0.03 40 10 38 12 Example 5 Synthesis MA PGEE PGMEA PGME DIW Example 5 (parts by mass) 1 0.03 40 10 38 12 Example 6 Synthesis MA PGEE PGMEA PGME DIW Example 6 (parts by mass) 1 0.03 40 10 38 12 Example 7 Synthesis MA PGEE PGMEA PGME DIW Example 7 (parts by mass) 1 0.03 40 10 38 12 Example 8 Synthesis MA PGEE PGMEA PGME DIW Example 8 (parts by mass) 1 0.03 40 10 38 12 Example 9 Synthesis MA PGEE PGMEA PGME DIW Example 9 (parts by mass) 1 0.03 40 10 38 12 Example 10 Synthesis MA PGEE PGMEA PGME DIW Example 10 (parts by mass) 1 0.03 40 10 38 12 Example 11 Synthesis MA PGEE PGMEA PGME DIW Example 11 (parts by mass) 1 0.03 40 10 38 12 Example 12 Synthesis MA PGEE PGMEA PGME DIW Example 12 (parts by mass) 1 0.03 40 10 38 12

TABLE-US-00002 TABLE 2 Si polymer solution Additive 1 Additive 2 Solvent Example 13 Synthesis MA PGEE PGMEA PGME DIW Example 13 (parts by mass) 1 0.03 40 10 38 12 Example 14 Synthesis MA PGEE PGMEA PGME DIW Example 14 (parts by mass) 1 0.03 40 10 38 12 Example 15 Synthesis MA PGEE PGMEA PGME DIW Example 15 (parts by mass) 1 0.03 40 10 38 12 Example 16 Synthesis MA PGEE PGMEA PGME DIW Example 16 (parts by mass) 1 0.03 40 10 38 12 Example 17 Synthesis MA PGEE PGMEA PGME DIW Example 17 (parts by mass) 1 0.03 40 10 38 12 Example 18 Synthesis NfA DIW Example 18 (parts by mass) 1 0.01 100  Example 19 Synthesis NfA DIW Example 19 (parts by mass) 1 0.01 100  Example 20 Synthesis NfA DIW Example 20 (parts by mass) 1 0.01 100  Example 21 Synthesis NfA DIW Example 21 (parts by mass) 1 0.01 100  Example 22 Synthesis NfA DIW Example 22 (parts by mass) 1 0.01 100  Comparative Comparative MA PGEE PGMEA PGME DIW Example 1 Synthesis Example 1 (parts by mass) 1 0.03 40 10 38 12 Comparative Comparative MA TPSNO3 PGEE PGMEA PGME DIW Example 2 Synthesis Example 1 (parts by mass) 1 0.03 0.05 40 10 38 12

[0187] (Preparation of Organic Resist Underlayer Film)

[0188] 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.), 0.76 g (0.0040 mol) of p-toluenesulfonic acid monohydrate (available from Tokyo Chemical Industry Co., Ltd.), and 6.69 g of 1,4-dioxane (available from Kanto Chemical Co., Inc.), and the resultant mixture was stirred. The mixture was heated to 100° C. for dissolution, to thereby initiate polymerization. After the elapse of 24 hours, the mixture was left cool to 60° C. The mixture was then diluted with 34 g of chloroform (available from Kanto Chemical Co., Inc.) and reprecipitated in 168 g of methanol (available from Kanto Chemical Co., Inc.). The resultant precipitate was filtered and dried with a reduced pressure dryer at 80° C. for 24 hours, to thereby yield 9.37 g of a target polymer (Formula (F-1), hereinafter abbreviated as “PCzFL”).

##STR00063##

[0189] The results of .sup.1H-NMR analysis of PCzFL were as follows: .sup.1H-NMR (400 MHz, DMSO-d.sub.6): δ 7.03-7.55 (br, 12H), δ 7.61-8.10 (br, 4H), δ 11.18 (br, 1H).

[0190] 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.

[0191] Subsequently, 20 g of the resultant resin was mixed with 3.0 g of tetramethoxymethyl glycoluril (trade name: Powderlink 1174, available from 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 Dainippon Ink and Chemicals, Inc.) serving as a surfactant, and the mixture was dissolved in 88 g of propylene glycol monomethyl ether acetate, to thereby prepare a solution. Thereafter, the 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 a solution of an organic resist underlayer film-forming composition used for a lithography process using a multilayer film.

[0192] (Tests for Solvent Resistance and Developer Solubility)

[0193] Each of the Si-containing resist underlayer film-forming compositions prepared in Examples 1 to 22 and Comparative Examples 1 and 2 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 resist underlayer film. Thereafter, a solvent of propylene glycol monomethyl ether/propylene glycol monomethyl ether acetate (=7/3) was applied onto the Si-containing resist underlayer film and then spin-dried for determining a change in film thickness between before and after application of the solvent. Solvent resistance was evaluated as “Good” when a change in film thickness was less than 1%, or evaluated as “Not cured” when a change in film thickness was 1% or more.

[0194] Similarly, each of the Si-containing coating liquids prepared in Examples 1 to 22 and Comparative Examples 1 and 2 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 resist underlayer film. Thereafter, an alkaline developer (2.38% aqueous TMAH solution) was applied onto the Si-containing resist underlayer film and then spin-dried for determining a change in film thickness between before and after application of the solvent. Developer resistance was evaluated as “Good” when a change in film thickness was less than 1%, or evaluated as “Not cured” when a change in film thickness was 1% or more.

TABLE-US-00003 TABLE 3 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

TABLE-US-00004 TABLE 4 Solvent resistance Developer resistance Example 13 Good Good Example 14 Good Good Example 15 Good Good Example 16 Good Good Example 17 Good Good Example 18 Good Good Example 19 Good Good Example 20 Good Good Example 21 Good Good Example 22 Good Good Comparative Example 1 Not cured Not cured Comparative Example 2 Good Good

[0195] (Measurement of Dry Etching Rate)

[0196] Dry etching rate was measured with the following etchers and etching gases.

[0197] Lam 2300 (available from Lam Research Co., Ltd.): CF.sub.4/CHF.sub.3/N.sub.2

[0198] RIE-10NR (available from SAMCO Inc.): O.sub.2

[0199] Each of the resist underlayer film-forming compositions prepared in Examples 1 to 22 and Comparative Example 2 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 coating film (thickness: 0.02 μm (for measurement of etching rate with CF.sub.4 gas), thickness: 0.02 μm (for measurement of etching rate with O.sub.2 gas)). Similarly, the organic resist underlayer film-forming composition was applied onto a silicon wafer with a spinner, to thereby form a coating film (thickness: 0.20 μm). The dry etching rate of the coating film was measured by using CF.sub.4/CHF.sub.3/N.sub.2 gas and O.sub.2 gas serving as etching gases, and was compared with the dry etching rate of the Si-containing coating film formed from each of the compositions of the Examples.

TABLE-US-00005 TABLE 5 Fluorine- Oxygen-containing gas containing gas Resistance etching rate (relative to organic resist (nm/min) underlayer film) Example 1 46 0.03 Example 2 50 0.02 Example 3 46 0.02 Example 4 43 0.02 Example 5 38 0.03 Example 6 43 0.03 Example 7 43 0.02 Example 8 46 0.02 Example 9 49 0.02 Example 10 49 0.03 Example 11 43 0.02 Example 12 46 0.02

TABLE-US-00006 TABLE 6 Fluorine- Oxygen-containing gas containing gas Resistance (relative etching rate to organic resist (nm/min) underlayer film) Example 13 53 0.02 Example 14 40 0.06 Example 15 46 0.03 Example 16 46 0.03 Example 17 46 0.03 Example 18 53 0.06 Example 19 50 0.04 Example 20 50 0.04 Example 21 48 0.03 Example 22 48 0.03 Comparative Example 2 30 0.02

[0200] [Formation of Resist Pattern by EUV Exposure: Positive Alkali Development]

[0201] The aforementioned organic underlayer film (layer A)-forming composition was applied onto a silicon wafer, and then baked on a hot plate at 215° C. for 60 seconds, to thereby form an organic underlayer film (layer A) having a thickness of 90 nm. Each of the resist underlayer film-forming composition solutions prepared in Examples 1 to 22 of the present invention and Comparative Example 2 was applied onto layer A by spin coating, and then heated at 215° C. for one minute, to thereby form a resist underlayer film (layer B) (20 nm). An EUV resist solution (methacrylate resin resist) was applied onto the hard mask by spin coating, and then heated to form an EUV resist layer (layer C). The EUV resist layer was exposed to light with an EUV exposure apparatus (NXE3300B, available from ASML) under the following conditions: NA: 0.33, a: 0.67/0.90, Dipole. After the light exposure, PEB was performed, and the resultant product was cooled on a cooling plate to room temperature, followed by development with an alkaline developer (2.38% aqueous TMAH solution) for 60 seconds and rinsing treatment, to thereby form a resist pattern. The resist pattern was evaluated for formation of a 20 nm line and space. The pattern shape was evaluated by observation of a cross section of the pattern.

[0202] In Table 7, “Good” indicates a shape between footing and undercut and a state of no significant residue in a space portion; “Collapse” indicates an unfavorable state of peeling and collapse of the resist pattern; and “Bridge” indicates an unfavorable state of contact between upper portions or lower portions of the resist pattern.

TABLE-US-00007 TABLE 7 Pattern shape 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

TABLE-US-00008 TABLE 8 Pattern shape Example 13 Good Example 14 Good Example 15 Good Example 16 Good Example 17 Good Example 18 Good Example 19 Good Example 20 Good Example 21 Good Example 22 Good Comparative Example 2 Good

[0203] [Formation of Resist Pattern by EUV Exposure: Negative Solvent Development]

[0204] The aforementioned organic underlayer film (layer A)-forming composition was applied onto a silicon wafer, and then baked on a hot plate at 215° C. for 60 seconds, to thereby form an organic underlayer film (layer A) having a thickness of 90 nm. Each of the resist underlayer film-forming composition solutions prepared in Examples 1 to 22 of the present invention and Comparative Example 2 was applied onto layer A by spin coating, and then heated at 215° C. for one minute, to thereby form a resist underlayer film (layer B) (20 nm). An EUV resist solution (methacrylate resin resist) was applied onto the hard mask by spin coating, and then heated to form an EUV resist layer (layer C). The EUV resist layer 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. After the light exposure, PEB 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 60 seconds and rinsing treatment, to thereby form a resist pattern. The resist pattern was evaluated for formation of a 22 nm line and space. The pattern shape was evaluated by observation of a cross section of the pattern.

[0205] In Table 9, “Good” indicates a shape between footing and undercut and a state of no significant residue in a space portion; “Collapse” indicates an unfavorable state of peeling and collapse of the resist pattern; and “Bridge” indicates an unfavorable state of contact between upper portions or lower portions of the resist pattern.

TABLE-US-00009 TABLE 9 Pattern shape 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

TABLE-US-00010 TABLE 10 Pattern shape Example 13 Good Example 14 Good Example 15 Good Example 16 Good Example 17 Good Example 18 Good Example 19 Good Example 20 Good Example 21 Good Example 22 Good Comparative Example 2 Good

[0206] (SPM, SC-1 Solubility Test)

[0207] Each of the Si-containing resist underlayer film-forming compositions prepared in Example 18 and Comparative Example 2 was applied onto a silicon wafer with a spinner, and then heated on a hot plate at 180° C. for one minute, to thereby form an Si-containing resist underlayer film. Thereafter, RS-30 (mixture of hydrogen peroxide and sulfuric acid) (available from Rasa Industries, LTD.) or hydrogen peroxide-aqueous ammonia was applied onto the Si-containing resist underlayer film and then spin-dried for determining a change in film thickness between before and after application of the solvent. Solubility was evaluated as “Good” when a change in film thickness was 90% or more, or evaluated as “Not dissolved” when a change in film thickness was less than 90%.

TABLE-US-00011 TABLE 11 SPM solution SC-1 solution Example 18 Good Good Comparative Example 2 Not dissolved Not dissolved

INDUSTRIAL APPLICABILITY

[0208] The present invention provides a resist underlayer film material that achieves a high etching rate during etching with halogen gas by a hydrolysis condensate (polysiloxane) containing a curing catalyst when a resist pattern is transferred onto an underlayer film in accordance with a reduction in the thickness of a resist film in a tri-layer process, and forms a resist underlayer film capable of being removed with a chemical after processing of a substrate.