FILM-FORMING COMPOSITION

Abstract

A film-forming composition including one selected from among a hydrolyzable silane compound, a hydrolysate of the compound, and a hydrolysis condensate of the compound, and a solvent, the film-forming composition wherein: the hydrolyzable silane compound contains a hydrolyzable silane having a cyano group in the molecule and being 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 a silicon atom and is an organic group containing a cyano group; R.sup.2 is a group bonded to a silicon atom via an Si—C bond, and is each independently a substitutable alkyl group, etc.; R.sup.3 is a group or atom bonded to a silicon atom, and is each independently a hydroxy group, an alkoxy group, an aralkyloxy group, an acyloxy group, or a halogen atom; a is an integer of 1; b is an integer of 0 to 2; and a+b is an integer of 1 to 3).

Claims

1. A film-forming composition comprising at least one selected from among a hydrolyzable silane compound, a hydrolysate of the compound, and a hydrolysis condensate of the compound, and a solvent, the film-forming composition being wherein: the hydrolyzable silane compound contains a hydrolyzable silane having a cyano group in the molecule and being 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 a silicon atom and is an organic group containing a cyano group; R.sup.2 is a group bonded to a silicon atom via an Si—C bond, and is each independently 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, an amino group, an amide group, an alkoxy group, or a sulfonyl group, or any combination of these; R.sup.3 is a group or atom bonded to a silicon atom, and is each independently a hydroxy group, an alkoxy group, an aralkyloxy group, an acyloxy group, or a halogen atom; a is an integer of 1; b is an integer of 0 to 2; and a+b is an integer of 1 to 3).

2. The film-forming composition according to claim 1, wherein the organic group containing a cyano group is an organic group prepared by substitution of one or more hydrogen atoms of an alkyl group selected from the group consisting of a chain alkyl group, a branched alkyl group, and a cyclic alkyl group with a cyano-containing group selected from among a cyano group (—CN) and a thiocyanato group (—S—CN).

3. The film-forming composition according to claim 1, wherein the composition comprises a hydrolysis condensate of the hydrolyzable silane compound.

4. The film-forming composition according to claim 1, wherein the hydrolyzable silane compound further contains at least one selected from among a hydrolyzable silane of the following Formula (2):
R.sup.4.sub.cSi(R.sup.5).sub.4−c  (2) (wherein R.sup.4 is a group bonded to a silicon atom via an Si—C bond, and is each independently 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, an amino group, an amide group, an alkoxy group, or a sulfonyl group, or any combination of these; R.sup.5 is a group or atom bonded to a silicon atom, and is each independently an alkoxy group, an aralkyloxy group, an acyloxy group, or a halogen atom; and c is an integer of 0 to 3), and a hydrolyzable silane of the following Formula (3):
[R.sup.6.sub.dSi(R.sup.7).sub.3−d].sub.2Y.sub.e  (3) (wherein R.sup.6 is a group bonded to a silicon atom via an Si—C bond, and is each independently 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, an amino group, an amide group, an alkoxy group, or a sulfonyl group, or any combination of these; R.sup.7 is a group or atom bonded to a silicon atom, and is each independently an alkoxy group, an aralkyloxy group, an acyloxy group, or a halogen atom; Y is a group bonded to a silicon atom via an Si—C bond, and is each independently an alkylene group or an arylene group; d is an integer of 0 or 1; and e is an integer of 0 or 1).

5. The film-forming composition according to claim 1, wherein the hydrolysis condensate is a hydrolysis condensate of the hydrolyzable silane compound containing a hydrolyzable silane having a cyano group in the molecule and being of Formula (1) in an amount of 0.1% by mole to 10% by mole relative to the entire amount of the hydrolyzable silane compound.

6. The film-forming composition according to claim 1, wherein hydrolysis of the hydrolyzable silane compound is performed with nitric acid serving as a hydrolysis catalyst.

7. The film-forming composition according to claim 1, wherein the solvent contains water.

8. The film-forming composition according to claim 1, wherein the composition further comprises a pH adjuster.

9. The film-forming composition according to claim 1, wherein the composition further comprises a surfactant.

10. The film-forming composition according to claim 1, wherein the composition is for forming a resist underlayer film for EUV lithography.

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

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

Description

EXAMPLES

[0291] 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.

[0292] [1] Synthesis of Polymer (Hydrolysis Condensate)

Synthesis Example 1

[0293] A 300-mL flask was charged with 25.6 g of tetraethoxysilane, 7.82 g of methyltriethoxysilane, 1.91 g of cyanoethyltriethoxysilane, and 53.0 g of acetone. While the resultant mixture was stirred with a magnetic stirrer, 11.7 g of 0.01 M aqueous nitric acid solution was added dropwise to the flask.

[0294] 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 acetate was added to the mixture, and then acetone, ethanol (i.e., reaction by-product), and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer).

[0295] Subsequently, propylene glycol monomethyl ether acetate was added to the solution so as to achieve a solvent proportion of propylene glycol monomethyl ether acetate of 100% and a solid residue content of 20% by mass at 140° C. The resultant polymer (corresponding to Formula (E1)) was found to have a weight average molecular weight Mw of 1,500 as determined by GPC in terms of polystyrene.

##STR00037##

Synthesis Example 2

[0296] A 300-mL flask was charged with 24.5 g of tetraethoxysilane, 11.0 g of cyanoethyltriethoxysilane, and 53.3 g of acetone. While the resultant mixture was stirred with a magnetic stirrer, 11.2 g of 0.01 M aqueous nitric acid solution was added dropwise to the flask.

[0297] 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, 72 g of propylene glycol monomethyl ether acetate was added to the mixture, and then acetone, ethanol (i.e., reaction by-product), and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer).

[0298] Subsequently, propylene glycol monomethyl ether acetate was added to the solution so as to achieve a solvent proportion of propylene glycol monomethyl ether acetate of 100% and a solid residue content of 20% by mass at 140° C. The resultant polymer (corresponding to Formula (E2)) was found to have a weight average molecular weight Mw of 1,300 as determined by GPC in terms of polystyrene.

##STR00038##

Synthesis Example 3

[0299] A 300-mL flask was charged with 25.2 g of tetraethoxysilane, 7.71 g of methyltriethoxysilane, 2.45 g of 5-(triethoxysilyl)bicyclo(2,2,1)heptyl-2-carbonitrile, and 53.1 g of acetone. While the resultant mixture was stirred with a magnetic stirrer, 11.5 g of 0.01 M aqueous nitric acid solution was added dropwise to the flask.

[0300] 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 acetate was added to the mixture, and then acetone, ethanol (i.e., reaction by-product), and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer).

[0301] Subsequently, propylene glycol monomethyl ether acetate was added to the solution so as to achieve a solvent proportion of propylene glycol monomethyl ether acetate of 100% and a solid residue content of 20% by mass at 140° C. The resultant polymer (corresponding to Formula (E3)) was found to have a weight average molecular weight Mw of 1,700 as determined by GPC in terms of polystyrene.

##STR00039##

Synthesis Example 4

[0302] A 300-mL flask was charged with 22.7 g of tetraethoxysilane, 13.2 g of 5-(triethoxysilyl)bicyclo(2,2,1)heptyl-2-carbonitrile, and 53.8 g of acetone. While the resultant mixture was stirred with a magnetic stirrer, 10.4 g of 0.01 M aqueous nitric acid solution was added dropwise to the flask.

[0303] 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, 72 g of propylene glycol monomethyl ether acetate was added to the mixture, and then acetone, ethanol (i.e., reaction by-product), and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer).

[0304] Subsequently, propylene glycol monomethyl ether acetate was added to the solution so as to achieve a solvent proportion of propylene glycol monomethyl ether acetate of 100% and a solid residue content of 20% by mass at 140° C. The resultant polymer (corresponding to Formula (E4)) was found to have a weight average molecular weight Mw of 1,200 as determined by GPC in terms of polystyrene.

##STR00040##

Synthesis Example 5

[0305] A 300-mL flask was charged with 24.0 g of tetraethoxysilane, 5.87 g of methyltriethoxysilane, 2.33 g of 5-(triethoxysilyl)bicyclo(2,2,1)heptyl-2-carbonitrile, 3.40 g of triethoxysilylpropyldiallyl isocyanurate, and 53.4 g of acetone. While the resultant mixture was stirred with a magnetic stirrer, 11.0 g of 0.01 M aqueous nitric acid solution was added dropwise to the flask.

[0306] 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, 72 g of propylene glycol monomethyl ether acetate was added to the mixture, and then acetone, ethanol (i.e., reaction by-product), and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer).

[0307] Subsequently, propylene glycol monomethyl ether acetate was added to the solution so as to achieve a solvent proportion of propylene glycol monomethyl ether acetate of 100% and a solid residue content of 20% by mass at 140° C. The resultant polymer (corresponding to Formula (E5)) was found to have a weight average molecular weight Mw of 1,500 as determined by GPC in terms of polystyrene.

##STR00041##

Synthesis Example 6

[0308] A 300-mL flask was charged with 24.8 g of tetraethoxysilane, 6.07 g of methyltriethoxysilane, 2.41 g of 5-(triethoxysilyl)bicyclo(2,2,1)heptyl-2-carbonitrile, 2.18 g of bicyclo(2,2,1)heptenyltriethoxysilane, and 53.2 g of acetone. While the resultant mixture was stirred with a magnetic stirrer, 11.3 g of 0.01 M aqueous nitric acid solution was added dropwise to the flask.

[0309] 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, 72 g of propylene glycol monomethyl ether acetate was added to the mixture, and then acetone, ethanol (i.e., reaction by-product), and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer).

[0310] Subsequently, propylene glycol monomethyl ether acetate was added to the solution so as to achieve a solvent proportion of propylene glycol monomethyl ether acetate of 100% and a solid residue content of 20% by mass at 140° C. The resultant polymer (corresponding to Formula (E6)) was found to have a weight average molecular weight Mw of 1,500 as determined by GPC in terms of polystyrene.

##STR00042##

Synthesis Example 7

[0311] A 300-mL flask was charged with 24.3 g of tetraethoxysilane, 5.95 g of methyltriethoxysilane, 2.37 g of 5-(triethoxysilyl)bicyclo(2,2,1)heptyl-2-carbonitrile, 2.89 g of benzenesulfonamidepropyltriethoxysilane, and 53.3 g of acetone. While the resultant mixture was stirred with a magnetic stirrer, 11.1 g of 0.01 M aqueous nitric acid solution was added dropwise to the flask.

[0312] 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, 72 g of propylene glycol monomethyl ether acetate was added to the mixture, and then acetone, ethanol (i.e., reaction by-product), and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer).

[0313] Subsequently, propylene glycol monomethyl ether acetate was added to the solution so as to achieve a solvent proportion of propylene glycol monomethyl ether acetate of 100% and a solid residue content of 20% by mass at 140° C. The resultant polymer (corresponding to Formula (E7)) was found to have a weight average molecular weight Mw of 1,800 as determined by GPC in terms of polystyrene.

##STR00043##

Synthesis Example 8

[0314] A 300-mL flask was charged with 21.1 g of tetraethoxysilane, 6.19 g of methyltriethoxysilane, 2.05 g of 5-(triethoxysilyl)bicyclo(2,2,1)heptyl-2-carbonitrile, and 53.3 g of acetone. While the resultant mixture was stirred with a magnetic stirrer, a mixture of 26.1 g of 0.2 M aqueous nitric acid solution and 0.30 g of dimethylaminopropyltrimethoxysilane was added dropwise to the flask.

[0315] 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, 60 g of propylene glycol monomethyl ether was added to the mixture, and then acetone, methanol and ethanol (i.e., reaction by-products), and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer).

[0316] Subsequently, propylene glycol monomethyl ether was added to the solution so as to achieve a solvent proportion of propylene glycol monomethyl ether of 100% and a solid residue content of 20% by mass at 140° C. The resultant polymer (corresponding to Formula (E8)) was found to have a weight average molecular weight Mw of 1,700 as determined by GPC in terms of polystyrene.

##STR00044##

Synthesis Example 9

[0317] A 300-mL flask was charged with 24.8 g of tetraethoxysilane, 6.08 g of methyltriethoxysilane, 4.49 g of 3-thiocyanatopropyltriethoxysilane, and 53.2 g of acetone. While the resultant mixture was stirred with a magnetic stirrer, 11.4 g of 0.01 M aqueous nitric acid solution was added dropwise to the flask.

[0318] 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, 72 g of propylene glycol monomethyl ether acetate was added to the mixture, and then acetone, ethanol (i.e., reaction by-product), and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer).

[0319] Subsequently, propylene glycol monomethyl ether acetate was added to the solution so as to achieve a solvent proportion of propylene glycol monomethyl ether acetate of 100% and a solid residue content of 20% by mass at 140° C. The resultant polymer (corresponding to Formula (E9)) was found to have a weight average molecular weight Mw of 1,800 as determined by GPC in terms of polystyrene.

##STR00045##

Synthesis Example 10

[0320] A 300-mL flask was charged with 23.2 g of tetraethoxysilane, 12.6 g of 3-thiocyanatopropyltriethoxysilane, and 53.7 g of acetone. While the resultant mixture was stirred with a magnetic stirrer, 10.6 g of 0.01 M aqueous nitric acid solution was added dropwise to the flask.

[0321] 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, 72 g of propylene glycol monomethyl ether acetate was added to the mixture, and then acetone, ethanol (i.e., reaction by-product), and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer).

[0322] Subsequently, propylene glycol monomethyl ether acetate was added to the solution so as to achieve a solvent proportion of propylene glycol monomethyl ether acetate of 100% and a solid residue content of 20% by mass at 140° C. The resultant polymer (corresponding to Formula (E10)) was found to have a weight average molecular weight Mw of 1,600 as determined by GPC in terms of polystyrene.

##STR00046##

Comparative Synthesis Example 1

[0323] A 300-mL flask was charged with 24.1 g of tetraethoxysilane, 1.8 g of phenyltrimethoxysilane, 9.5 g of methyltriethoxysilane, and 53.0 g of acetone. While the resultant mixture was stirred with a magnetic stirrer, 11.7 g of 0.01 M aqueous nitric acid solution was added dropwise to the mixture.

[0324] 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 and ethanol (i.e., reaction by-products), and water were distilled off under reduced pressure, followed by concentration, to thereby prepare an aqueous solution of a hydrolysis condensate (polymer).

[0325] Subsequently, propylene glycol monomethyl ether was added to the solution so as to achieve a solvent proportion of propylene glycol monomethyl ether of 100% and a solid residue content of 13% by mass at 140° C. The resultant polymer (corresponding to Formula (C1)) was found to have a weight average molecular weight Mw of 1,400 as determined by GPC in terms of polystyrene.

##STR00047##

[0326] [2] Preparation of Composition to be Applied to Resist Pattern

[0327] Each of the polysiloxanes (polymers) prepared in the aforementioned Synthesis Examples, an additive, 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 composition to be applied to a resist pattern. In Table 1, the amount of each component added is shown by part(s) by mass.

[0328] 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.

[0329] In Table 1, DIW denotes ultrapure water; PGEE, propylene glycol monoethyl ether; PGMEA, propylene glycol monoethyl ether acetate; and PGME, propylene glycol monoethyl ether.

[0330] Furthermore, MA denotes maleic acid; TPSNO3, triphenylsulfonium nitrate; TPSTFA, triphenylsulfonium trifluoroacetate; TPSML, triphenylsulfonium maleate; TPSCl, triphenylsulfonium chloride; BTEAC, benzyltriethylammonium chloride; TMANO3, tetramethylammonium nitrate; and TPSCS, triphenylsulfonium camphorsulfonate.

TABLE-US-00001 TABLE 1 Polymer Additive 1 Additive 2 Solvent Example 1 Synthesis MA TPSNO3 PGEE PGMEA PGME DIW Example 1 (part(s) by mass) 1 0.03 0.05 40 10 38 12 Example 2 Synthesis MA TPSTFA PGEE PGMEA PGME DIW Example 2 (part(s) by mass) 1 0.03 0.05 40 10 38 12 Example 3 Synthesis MA TPSML PGEE PGMEA PGME DIW Example 3 (part(s) by mass) 1 0.03 0.05 40 10 38 12 Example 4 Synthesis MA TPSC1 PGEE PGMEA PGME DIW Example 4 (part(s) by mass) 1 0.03 0.05 40 10 38 12 Example 5 Synthesis MA BTEAC PGEE PGMEA PGME DIW Example 5 (part(s) by mass) 1 0.03 0.05 40 10 38 12 Example 6 Synthesis MA TMANO3 PGEE PGMEA PGME DIW Example 6 (part(s) by mass) 1 0.03 0.05 40 10 38 12 Example 7 Synthesis MA TPSNO3/ PGEE PGMEA PGME DIW Example 7 TPSCS (part(s) by mass) 1 0.03 0.05/0.05 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 TPSNO3 PGEE PGMEA PGME DIW Example 9 (part(s) by mass) 1 0.03 0.05 40 10 38 12 Example 10 Synthesis MA TPSML PGEE PGMEA PGME DIW Example _10 (part(s) by mass) 1 0.03 0.05 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 1 (part(s) by mass) 1 0.03 0.05 40 10 38 12

[0331] [3] Preparation of Organic Resist Underlayer Film-Forming Composition

[0332] 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.

[0333] 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.

[0334] 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 (X) (hereinafter abbreviated as “PCzFL”).

[0335] 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), δ7.61-8.10 (br, 4H), δ11.18 (br, 1H).

[0336] 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.

##STR00048##

[0337] 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 MEGAFACE 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 resist underlayer film-forming composition used for a lithographic process using a multilayer film.

[0338] [4] Solvent Resistance Test and Developer Solubility Test

[0339] Each of the compositions prepared in Examples 1 to 10 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. The thickness of the resultant underlayer film was measured.

[0340] Subsequently, a mixed solvent of propylene glycol monomethyl ether/propylene glycol monomethyl ether acetate (7/3 (V/V)) was applied onto the Si-containing resist underlayer film, and then spin-dried. The thickness of the underlayer film was measured after application of the mixed solvent, 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 1% or less or 1% or more, respectively, on the basis of the thickness before application of the mixed solvent.

[0341] Separately, an alkaline developer (2.38% aqueous TMAH solution) was applied onto an Si-containing resist underlayer film formed on a silicon wafer in the same manner as described above, and then spin-dried. The thickness of the underlayer film was measured after application of the developer, 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 1% or less or 1% or more, respectively, on the basis of the thickness before application of the developer.

[0342] The results are shown in Table 2.

TABLE-US-00002 TABLE 2 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 Comparative Example 1 Not cured Not cured Comparative Example 2 Good Good

[0343] [5] Measurement of Dry Etching Rate

[0344] The following etchers and etching gases were used for measurement of dry etching rate.

[0345] Lam2300 (available from Lam Research Co., Ltd.): CF.sub.4/CHF.sub.3/N.sub.2 (fluorine-containing gas)

[0346] RIE-10NR (available from SAMCO Inc.): O.sub.2 (oxygen-containing gas)

[0347] Each of the compositions prepared in Examples 1 to 10 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 resist underlayer film (thickness: 0.02 μm).

[0348] Similarly, the aforementioned organic resist 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 resist underlayer film (thickness: 0.20 μm).

[0349] The resultant silicon wafer provided with the Si-containing resist underlayer 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 resist 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.

[0350] The dry etching rate with O.sub.2 gas was expressed as the ratio (resistance) relative to the dry etching rate of the organic resist underlayer film.

TABLE-US-00003 TABLE 3 Etching rate with Oxygen-containing gas fluorine- resistance containing gas (relative to organic resist (nm/min) underlayer film) Example 1 35 0.02 Example 2 40 0.03 Example 3 33 0.02 Example 4 38 0.03 Example 5 38 0.02 Example 6 35 0.02 Example 7 37 0.02 Example 8 39 0.02 Example 9 40 0.02 Example 10 45 0.03 Comparative Example 2 30 0.02

[0351] [6] Formation of Resist Pattern by EUV Exposure: Negative Solvent Development

[0352] The aforementioned organic resist underlayer film-forming composition was applied onto a silicon wafer with a spinner, 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.

[0353] The composition prepared in Example 1 was applied onto the organic underlayer film by spin coating, and then heated at 215° C. for one minute, to thereby form a resist underlayer film (layer B) (20 nm).

[0354] An EUV resist solution (methacrylate resin-based resist) was applied onto the resist underlayer film by spin coating, and then heated at 130° C. for one minute, to thereby form an EUV resist film (layer C). 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.

[0355] After the light exposure, post exposure bake (PEB, 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 60 seconds and rinsing treatment, to thereby form a resist pattern.

[0356] Each of the compositions prepared in Examples 2 to 10 and Comparative Example 2 was used, and a resist pattern was formed through the same procedure as described above.

[0357] 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.

[0358] 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 4.

TABLE-US-00004 TABLE 4 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 Comparative Example 2 Collapse