Composition for forming metal-containing film and patterning process

Abstract

To provide: a composition for forming a resist underlayer film to be used for forming a resist underlayer film capable of contributing to sensitivity enhancement while keeping LWR of an upper layer resist; and a patterning process using this composition.SOLUTION: A composition for forming a metal-containing film contains (A) a silicon-containing polymer containing polysiloxane, polycarbosilane or polysilane, (B) a metal source, and (C) an organic solvent. The metal source (B) is a salt of a metal selected from Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi with a monovalent to tetravalent carboxylic acid having 1 to 30 carbon atoms, or a complex of the metal with a β-diketone.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a composition for forming a metal-containing film that can be used for fine patterning by a multilayer resist method in a semiconductor device manufacturing process, and a patterning method using the composition.

Background Art

[0002] With the high integration and high speed of LSIs, the miniaturization of pattern rules has been rapidly progressing. In particular, logic devices used in smartphones and the like have been driving miniaturization, and logic devices with a 10 nm node are being mass-produced using a multiple exposure (multi-patterning lithography) process by ArF lithography.

[0003] For the next lithography of the 7 nm node and 5 nm node, problems such as high cost due to multiple exposures and overlay accuracy problems in multiple exposures have become apparent, and the advent of EUV lithography that can reduce the number of exposures has been expected.

[0004] Extreme ultraviolet light (EUV) with a wavelength of 13.5 nm has a wavelength that is 1 / 10 or less that of an ArF excimer laser with a wavelength of 193 nm. Therefore, EUV lithography is expected to have high contrast and high resolution. Since EUV has a short wavelength and a high energy density, an acid generator is sensitive to a small amount of photons. The number of photons in EUV exposure is said to be 1 / 14 of that in ArF exposure. In EUV exposure, a phenomenon in which line width roughness (LWR) and critical dimension uniformity (CDU) of holes deteriorate due to photon variation has been regarded as a problem (Non-Patent Document 1). Furthermore, the possibility of uneven distribution and aggregation of the base polymer and acid generator, and the influence of acid diffusion generated from the acid generator have also been pointed out.

[0005] As a countermeasure, for example, it is possible to reduce LWR by lowering the post-exposure bake (PEB) temperature, but the sensitivity of the EUV resist will decrease. Furthermore, increasing the amount of quencher added also reduces LWR, but this method also results in decreased sensitivity. In order to put EUV resist into practical use, it is necessary to break the trade-off relationship between sensitivity and LWR.

[0006] In order for EUV lithography to be put into practical use as a mass production process for semiconductor devices, many issues need to be solved. Among them, the characteristic that particularly needs improvement is to increase the sensitivity while maintaining LWR. In Patent Document 1, a method of forming an underlayer film containing a sensitizer that absorbs EUV light and generates secondary electrons has been reported. In Patent Document 2, it has been reported that a thermosetting silicon-containing material containing iodine can contribute to improving the sensitivity while maintaining the LWR of the upper layer resist. However, in the above material design, the introduction rate of elements with a large light absorption is limited, and it is considered that a material design that contributes more to improving the sensitivity of the resist is required.

[0007] Regarding the above problems, a method of introducing a resist underlayer film containing a metal element with a large EUV light absorption coefficient can be considered. In Patent Document 3, a composition of a spin-on material containing metal oxide nanoparticles and an organic polymer has been reported. Although the pattern formation evaluation of the EUV resist is not described, it is assumed that an underlayer film of the resist containing a large amount of a metal element with a large light absorption can be formed. However, since the film formed using metal nanoparticles has crystallinity, when nanoparticles are used as the underlayer film material of the resist, there is a risk of deteriorating the line width roughness (LWR) of the pattern when the substrate to be processed is etched.

[0008] In Patent Document 4, a resist composition containing a polymer having a repeating unit having a carboxyl group or phenolic hydroxyl group substituted with an acid-labile group, an acid generator, and a carboxylate or β-diketone complex of various metals has been proposed. In this case, the acid generated from the acid generator is trapped by ion-exchanging with a carboxylate or β-diketone complex of various metals. The carboxylate or β-diketone complex of a metal functions as an acid catalyst quencher and is effective for controlling acid diffusion, but does not actively improve the sensitivity. A breakthrough for controlling acid diffusion while increasing the sensitivity is desired.

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Non-Patent Documents

[0010]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0011] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a composition for forming a metal-containing film that can contribute to improving the sensitivity while maintaining the LWR of the upper-layer resist, and a pattern formation method using this composition.

Means for Solving the Problems

[0012] In order to solve the above problems, in the present invention, A metal-containing film-forming composition comprising (A) a silicon-containing polymer containing polysiloxane, polycarbosilane, or polysilane, (B) a metal source, and (C) an organic solvent, wherein the (B) metal source is a salt of a metal selected from Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi and a monovalent to tetravalent carboxylic acid having 1 to 30 carbon atoms, or a complex of the metal and β-diketones, is provided.

[0013] With such a metal-containing film-forming composition, a resist underlayer film or an intermediate film that can contribute to improving the sensitivity while maintaining the LWR of the upper-layer resist can be formed.

[0014] Further, it is preferable that the polysiloxane of the component (A) contains any one or more of a repeating unit represented by the following general formula (Sx-1), a repeating unit represented by the following general formula (Sx-2), and a partial structure represented by the following general formula (Sx-3).

Chemical formula

[0015] By using such a metal-containing film-forming composition, it becomes possible to improve the adhesion to the resist pattern and prevent the collapse of the fine pattern.

[0016] At this time, in the formulas (Sx-1) to (Sx-3), it is preferable that at least one of R a to R c is an organic group having one or more carbon-oxygen single bonds or carbon-oxygen double bonds.

[0017] By using such a composition for forming a metal-containing film, it becomes possible to improve the adhesion to the resist pattern and prevent the collapse of the fine pattern.

[0018] Moreover, it is preferable that the polycarbosilane as the component (A) contains a unit structure represented by the following general formula (Sy-1).

Chemical formula

[0019] By using such a composition for forming a metal-containing film, it becomes possible to improve the adhesion to the resist pattern and prevent the collapse of the fine pattern.

[0020] Moreover, it is preferable that the polysilane as the component (A) contains a repeating unit represented by the following general formula (Sz-1). (R 9 R 10 R 11 Si) a2 (R 12 R 13 Si) a3 (R 14 Si) a4 (Si) a5 (Sz-1) (In the formula, R 9 , R 10 , R 11 , R 12 , R 13 , and R 14 are each a methyl group, a phenyl group, or a hydroxy group. a2, a3, a4, and a5 are molar fractions, and a2 + a3 + a4 + a5 = 1, 0 ≦ a2 ≦ 1, 0 ≦ a3 ≦ 1, 0 ≦ a4 ≦ 1, 0 ≦ a5 ≦ 1.)

[0021] By using such a composition for forming a metal-containing film, it becomes possible to improve the adhesion to the resist pattern and prevent the collapse of fine patterns.

[0022] Further, it is preferable that the (B) metal source is a salt of the metal and a monovalent to tetravalent carboxylic acid having 1 to 30 carbon atoms.

[0023] With such a composition for forming a metal-containing film, it is possible to form a resist underlayer film or an intermediate film that can contribute to improving the sensitivity while maintaining the LWR of the upper resist. In addition, since it is possible to form a resist underlayer film having excellent dry etching resistance when transferring a pattern to the underlayer film, the upper resist pattern can be transferred to the substrate to be processed with high precision.

[0024] Further, it is preferable that the (B) metal source has a structure represented by the following formula (B-1).

Chemical formula

[0025] With such a composition for forming a metal-containing film, it is possible to form a resist underlayer film or an intermediate film that can contribute to improving the sensitivity while maintaining the LWR of the upper resist. In addition, since it is possible to form a resist underlayer film having excellent dry etching resistance when transferring a pattern to the underlayer film, the upper resist pattern can be transferred to the substrate to be processed with high precision.

[0026] At this time, it is preferable that R1 in the formula (B-1) is a saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms.

[0027] With such a (B) metal source, when used in a composition for forming a metal-containing film, the solubility in an organic solvent becomes good, the film-forming property is excellent, and a resist underlayer film or an intermediate film with few defects can be formed.

[0028] Also at this time, it is preferable that R1 in the formula (B-1) is a branched alkyl group having 3 to 10 carbon atoms.

[0029] If it is such a metal source (B), when used in the composition for forming a metal-containing film, the solubility in an organic solvent becomes good, the film-forming property is excellent, and a resist underlayer film or intermediate film with few defects can be formed.

[0030] Moreover, it is preferable that the metal of the metal source (B) is Sn.

[0031] If it is such a composition for forming a metal-containing film, a resist underlayer film or intermediate film that can contribute to improving the sensitivity while maintaining the LWR of the upper-layer resist can be formed.

[0032] Also, it is preferable that the composition further contains one or more of (D) a crosslinking agent, (E) an acid generator, (F) a surfactant, and (G) a pigment.

[0033] These additives can be added to the composition of the present invention as necessary.

[0034] Moreover, it is preferable that the organic solvent (C) is a mixture of one or more organic solvents having a boiling point of less than 180°C and one or more organic solvents ((C') high-boiling solvent) having a boiling point of 180°C or higher.

[0035] By imparting fluidity to the composition for forming a metal-containing film by adding a high-boiling solvent, the occurrence of coating defects due to drying of the composition for forming a metal-containing film can be suppressed.

[0036] Also in the present invention, a method for forming a pattern on a substrate to be processed, (I-1) A step of forming a metal-containing film by applying the above composition for forming a metal-containing film on a substrate to be processed and then performing heat treatment, (I-2) A step of forming a resist upper-layer film using a photoresist material on the metal-containing film, (I-3) After pattern-exposing the resist upper layer film, developing it with a developer to form a pattern in the resist upper layer film; (I-4) Using the resist upper layer film on which the pattern is formed as a mask, transferring the pattern to the metal-containing film by dry etching, and (I-5) Using the metal-containing film on which the pattern is formed as a mask to process the substrate to be processed and form a pattern on the substrate to be processed. provided is a pattern formation method having the above steps.

[0037] By the above pattern formation method using a two-layer resist process, a fine pattern can be formed on a workpiece (substrate to be processed).

[0038] Further, in the present invention, a method for forming a pattern on a substrate to be processed, comprising: (II-1) forming an organic resist lower layer film on the substrate to be processed; (II-2) coating the above composition for forming a metal-containing film on the organic resist lower layer film and then performing heat treatment to form a metal-containing film; (II-3) forming a resist upper layer film on the metal-containing film using a photoresist material; (II-4) after pattern-exposing the resist upper layer film, developing it with a developer to form a pattern in the resist upper layer film; (II-5) using the resist upper layer film on which the pattern is formed as a mask, transferring the pattern to the metal-containing film by dry etching; (II-6) using the metal-containing film to which the pattern is transferred as a mask, transferring the pattern to the organic resist lower layer film by dry etching, and (II-7) using the organic resist lower layer film on which the pattern is formed as a mask to process the substrate to be processed and form a pattern on the substrate to be processed. provided is a pattern formation method having the above steps.

[0039] By the pattern formation method using the above three-layer resist process, a fine pattern can be formed on a workpiece with high precision.

[0040] Also, in the step (I-3), it is preferable to perform the pattern exposure using EUV light.

[0041] Also, in the step (II-4), it is preferable to perform the pattern exposure using EUV light.

[0042] Since the composition for forming a metal-containing film of the present invention contains metal atoms with a large light absorption, in EUV lithography, it is possible to form a resist underlayer film or an intermediate film that can contribute to improving the sensitivity while maintaining the LWR of the upper layer resist.

Advantages of the Invention

[0043] For the composition for forming a metal-containing film of the present invention, since the metal salt structure is decomposed by heat treatment and metal ions are desorbed to form a metal oxide, a resist underlayer film with a high metal content can be provided. Because it contains many metal atoms with a large light absorption, it has the characteristic that the sensitizing effect by secondary electrons generated during exposure can be expected in EUV lithography. Furthermore, since the above metal atoms have a large atomic weight, they have a high effect of suppressing acid diffusion from the upper layer resist into the resist underlayer film, and have the characteristic that the sensitivity can be increased while maintaining the LWR performance originally possessed by the upper layer resist film. Also, since it contains polysiloxane or polysilane having excellent adhesion to the upper layer resist pattern, it is effective in suppressing the collapse of fine patterns and can provide a very effective pattern formation method in lithography using EUV light.

Brief Description of the Drawings

[0044]

Figure 1

Embodiments for Carrying Out the Invention

[0045] As described above, in the fine patterning process using a multilayer resist method, there has been a demand for the development of a composition for forming a metal-containing film that can contribute to improving the sensitivity while maintaining the LWR of the upper-layer resist, and a patterning method using the composition.

[0046] The present inventors focused on a metal material having a large absorption of EUV light and conducted intensive studies. The metal oxide film formed by spin coating was one candidate, but it had poor adhesion to the upper-layer resist film and it was difficult to suppress the collapse of fine patterns. The present inventors have found that a composition for forming a metal-containing film containing a silicon-containing polymer and a predetermined metal compound can form a resist underlayer film or an intermediate film having excellent adhesion to the upper-layer resist film and containing a large amount of a metal element having a large EUV light absorption, and completed the present invention.

[0047] That is, the present invention is a composition for forming a metal-containing film containing (A) a silicon-containing polymer containing polysiloxane (Sx), polycarbosilane (Sy), or polysilane (Sz), (B) a metal source, and (C) an organic solvent, wherein the (B) metal source is a salt of a metal selected from Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi and a monovalent to tetravalent carboxylic acid having 1 to 30 carbon atoms, or a complex of the metal and β-diketones.

[0048] Hereinafter, the present invention will be described in detail, but the present invention is not limited thereto.

[0049] <(A) Silicon-containing polymer> The (A) silicon-containing polymer contained in the composition for forming a metal-containing film of the present invention contains polysiloxane (Sx), polycarbosilane (Sy), or polysilane (Sz).

[0050] If it is a composition for forming a metal-containing film containing such a resin, a resist underlayer film or an intermediate film having excellent adhesion to the resist upper-layer film pattern can be formed.

[0051] <Polysiloxane (Sx)> The polysiloxane (Sx) preferably contains any one or more of the repeating units represented by the following general formula (Sx-1), the repeating units represented by the following general formula (Sx-2), and the partial structure represented by the following general formula (Sx-3). [Chemical formula] (In the formula, R a , R b , R c are each independently a monovalent organic group having 1 to 30 carbon atoms which may be the same or different.)

[0052] The above polysiloxane (hereinafter also referred to as a thermally crosslinkable polysiloxane) (Sx) can be produced by hydrolytic condensation of the following hydrolyzable monomer (Sm).

[0053] Specific examples of the hydrolyzable monomer (Sm) include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetraisopropoxysilane, trimethoxysilane, triethoxysilane, tripropoxysilane, triisopropoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltriisopropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltripropoxysilane, ethyltriisopropoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltripropoxysilane, vinyltriisopropoxysilane, propyltrimethoxysilane, propyltriethoxysilane, propyltripropoxysilane, propyltriisopropoxysilane, isopropyltrimethoxysilane, isopropyltriethoxysilane, isopropyltripropoxysilane, isopropyltriisopropoxysilane, butyltrimethoxysilane, butyltriethoxysilane, butyltripropoxysilane, butyltriisopropoxysilane, sec-butyltrimethoxysilane, sec-butyltriethoxysilane, sec-butyltripropoxysilane, sec-butyltriisopropoxysilane, t-butyltrimethoxysilane, t-butyltriethoxysilane, t-butyltripropoxysilane, t-butyltriisopropoxysilane, cyclopropyltrimethoxysilane, cyclopropyltriethoxysilane, cyclopropyltripropoxysilane, cyclopropyltriisopropoxysilane, cyclobutyltrimethoxysilane, cyclobutyltriethoxysilane, cyclobutyltripropoxysilane, cyclobutyltriisopropoxysilane, cyclopentyltrimethoxysilane, cyclopentyltriethoxysilane, cyclopentyltripropoxysilane, cyclopentyltriisopropoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, cyclohexyltripropoxysilane, cyclohexyltriisopropoxysilane, cyclohexenyltrimethoxysilane, cyclohexenyltriethoxysilane, cyclohexenyltripropoxysilane, cyclohexenyltriisopropoxysilane, cyclohexenylethyltrimethoxysilane,Cyclohexenylethyltriethoxysilane, cyclohexenylethyltripropoxysilane, cyclohexenylethyltriisopropoxysilane, cyclooctyltrimethoxysilane, cyclooctyltriethoxysilane, cyclooctyltripropoxysilane, cyclooctyltriisopropoxysilane, cyclopentadienylpropyltrimethoxysilane, cyclopentadienylpropyltriethoxysilane, cyclopentadienylpropyltripropoxysilane, cyclopentadienylpropyltriisopropoxysilane, bicycloheptenyltrimethoxysilane, bicycloheptenyltriethoxysilane, bicycloheptenyltripropoxysilane, bicycloheptenyltriisopropoxysilane, bicycloheptyltrimethoxysilane, bicycloheptyltriethoxysilane, bicycloheptyltripropoxysilane, bicycloheptyltriisopropoxysilane, adamantyltrimethoxysilane, adamantyltriethoxysilane, adamantyltripropoxysilane, adamantyltriisopropoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltripropoxysilane, phenyltriisopropoxysilane, benzyltrimethoxysilane, benzyltriethoxysilane, benzyltripropoxysilane, benzyltriisopropoxysilane, anisyltrimethoxysilane, anisyltriethoxysilane, anisyltripropoxysilane, anisyltriisopropoxysilane, tolyltrimethoxysilane, tolyltriethoxysilane, tolyltripropoxysilane, tolyltriisopropoxysilane, phenethyltrimethoxysilane, phenethyltriethoxysilane, phenethyltripropoxysilane, phenethyltriisopropoxysilane, naphthyltrimethoxysilane, naphthyltriethoxysilane, naphthyltripropoxysilane, naphthyltriisopropoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, methylethyldimethoxysilane, methylethyldiethoxysilane, dimethyldipropoxysilane, dimethyldiisopropoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, diethyldipropoxysilane, diethyldiisopropoxysilane, dipropyldimethoxysilane, dipropyldiethoxysilane,Dipropyldipropoxysilane, dipropyldiisopropoxysilane, diisopropyldimethoxysilane, diisopropyldiethoxysilane, diisopropyldipropoxysilane, diisopropyldiisopropoxysilane, dibutyldimethoxysilane, dibutyldiethoxysilane, dibutyldipropoxysilane, dibutyldiisopropoxysilane, di-sec-butyldimethoxysilane, di-sec-butyldiethoxysilane, di-sec-butyldipropoxysilane, di-sec-butyldiisopropoxysilane, di-t-butyldimethoxysilane, di-t-butyldiethoxysilane, di-t-butyldipropoxysilane, di-t-butyldiisopropoxysilane, dicyclopropyldimethoxysilane, dicyclopropyldiethoxysilane, dicyclopropyldipropoxysilane, dicyclopropyldiisopropoxysilane, dicyclobutyldimethoxysilane, dicyclobutyldiethoxysilane, dicyclobutyldipropoxysilane, dicyclobutyldiisopropoxysilane, dicyclopentyldimethoxysilane, dicyclopentyldiethoxysilane, dicyclopentyldipropoxysilane, dicyclopentyldiisopropoxysilane, dicyclohexyldimethoxysilane, dicyclohexyldiethoxysilane, dicyclohexyldipropoxysilane, dicyclohexyldiisopropoxysilane, dicyclohexenyldimethoxysilane, dicyclohexenyldiethoxysilane, dicyclohexenyldipropoxysilane, dicyclohexenyldiisopropoxysilane, dicyclohexenylethyldimethoxysilane, dicyclohexenylethyldiethoxysilane, dicyclohexenylethyldipropoxysilane, dicyclohexenylethyldiisopropoxysilane, dicyclooctyldimethoxysilane, dicyclooctyldiethoxysilane, dicyclooctyldipropoxysilane, dicyclooctyldiisopropoxysilane, dicyclopentadienylpropyldimethoxysilane, dicyclopentadienylpropyldiethoxysilane, dicyclopentadienylpropyldipropoxysilane, dicyclopentadienylpropyldiisopropoxysilane, bis(bicycloheptenyl)dimethoxysilane, bis(bicycloheptenyl)diethoxysilane, bis(bicycloheptenyl)dipropoxysilane,Examples thereof include bis(bicycloheptenyl)diisopropoxysilane, bis(bicycloheptyl)dimethoxysilane, bis(bicycloheptyl)diethoxysilane, bis(bicycloheptyl)dipropoxysilane, bis(bicycloheptenyl)diisopropoxysilane, diadamantyldimethoxysilane, diadamantyldiethoxysilane, diadamantyldipropoxysilane, diadamantyldiisopropoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane, diphenyldipropoxysilane, diphenyldiisopropoxysilane, trimethylmethoxysilane, trimethylethoxysilane, dimethylethylmethoxysilane, dimethylethylethoxysilane, dimethylphenylmethoxysilane, dimethylphenylethoxysilane, dimethylbenzylmethoxysilane, dimethylbenzylethoxysilane, dimethylphenethylmethoxysilane, dimethylphenethylethoxysilane, etc.

[0054] As the hydrolyzable monomer (Sm), preferably, tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, isopropyltrimethoxysilane, isopropyltriethoxysilane, butyltrimethoxysilane, butyltriethoxysilane, isobutyltrimethoxysilane, isobutyltriethoxysilane, allyltrimethoxysilane, allyltriethoxysilane, cyclopentyltrimethoxysilane, cyclopentyltriethoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, cyclohexenyltrimethoxysilane, cyclohexenyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, benzyltrimethoxysilane, benzyltriethoxysilane, phenethyltrimethoxysilane, phenethyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, methylethyldimethoxysilane, methylethyldiethoxysilane, dipropyldimethoxysilane, dibutyldimethoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane, trimethylmethoxysilane, dimethylethylmethoxysilane, dimethylphenylmethoxysilane, dimethylbenzylmethoxysilane, dimethylphenethylmethoxysilane, etc. can be exemplified.

[0055] As the above R corresponding to the compounds exemplified above as the hydrolyzable monomer (Sm) a , R b , R c As another example of the organic group represented by, an organic group having one or more carbon-oxygen single bonds or carbon-oxygen double bonds can be mentioned. Specifically, it is an organic group having one or more groups selected from the group consisting of an ether bond, an ester bond, an alkoxy group, a hydroxy group, etc. As this example, those represented by the following general formula (Sm-R) can be mentioned.

[0056] (P-Q1-(S1)v1 -Q2-) u -(T) v2 -Q3-(S2) v3 -Q4- (Sm-R) (In the general formula (Sm-R), P is a hydrogen atom, a cyclic ether group, a hydroxyl group, an alkoxy group having 1 to 4 carbon atoms, an alkylcarbonyloxy group having 1 to 6 carbon atoms, or an alkylcarbonyl group having 1 to 6 carbon atoms, and Q1, Q2, Q3, and Q4 are each independently -C q H (2q-p) P p -(wherein P is the same as above, p is an integer from 0 to 3, q is an integer from 0 to 10 (provided that q = 0 indicates a single bond), u is an integer from 0 to 3, and S1 and S2 each independently represent -O-, -CO-, -OCO-, -COO- or -OCOO-. v1, v2, and v3 each independently represent 0 or 1. T is a divalent group composed of a divalent atom other than carbon, an alicyclic ring, an aromatic ring or a heterocyclic ring. Examples of an alicyclic ring, an aromatic ring or a heterocyclic ring which may contain a hetero atom such as an oxygen atom as T are shown below. The position where Q2 and Q3 are bonded in T is not particularly limited, but can be appropriately selected in consideration of the reactivity due to steric factors and the availability of commercially available reagents used in the reaction.)

[0057]

Chemical formula

[0058] Preferred examples of the organic group having one or more carbon-oxygen single bonds or carbon-oxygen double bonds in the general formula (Sm-R) include the following. In the following formulas, (Si) is described to indicate the bonding position to Si.

[0059]

Chemical formula

[0060]

Chemical formula

[0061] In the formulas (Sx-1) to (Sx-3), when at least one of R a ~R c is an organic group having one or more carbon-oxygen single bonds or carbon-oxygen double bonds, the adhesion to the resist upper layer film pattern can be further improved.

[0062] Also, as examples of the organic groups of R a , R b , R c , organic groups containing a silicon-silicon bond can also be used. Specifically, the following can be mentioned. [Chemical formula]

[0063] Also, as examples of the organic groups of R a , R b , R c , organic groups having a protecting group decomposable by an acid can also be used. Specifically, the organic groups described in paragraphs

[0043] to

[0048] of JP-A-2013-167669 and the organic groups obtained from the silicon compounds shown in paragraph

[0056] of JP-A-2013-224279 can be mentioned.

[0064] Furthermore, as examples of the organic groups of R a , R b , R c , organic groups having a fluorine atom can also be used. Specifically, the organic groups obtained from the silicon compounds shown in paragraphs

[0059] to

[0065] paragraphs of JP-A-2012-53253 can be mentioned.

[0065] In EUV lithography, in order to improve the sensitivity of the resist upper layer film, it is preferable that the organic groups of R a , R b , R c include an organic group having a fluorine atom.

[0066] Furthermore, R a , Rb , R c As an example of the organic group of R, an organic group having an iodine atom can also be used. Specifically, the organic group obtained from the silicon compound shown in paragraphs

[0043] to

[0047] of JP-A-2023-116531 can be mentioned.

[0067] In EUV lithography, in order to improve the sensitivity of the resist upper layer film, R a , R b , R c Preferably, the organic group of R contains an organic group having an iodine atom.

[0068] In the above hydrolyzable monomer (Sm), one, two or three chlorine, bromine, iodine, acetoxy group, methoxy group, ethoxy group, propoxy group or butoxy group, etc. are bonded as hydrolyzable groups to the silicon shown in the above partial structure (Si).

[0069] 〔Synthesis method of polysiloxane (Sx)〕 (Synthesis method 1: Acid catalyst) The polysiloxane (thermally crosslinkable polysiloxane) (Sx) used in the present invention can be produced by subjecting one or a mixture of two or more hydrolyzable monomers (Sm) to hydrolysis and condensation in the presence of an acid catalyst.

[0070] The acid catalyst used at this time can include organic acids such as formic acid, acetic acid, oxalic acid, maleic acid, methanesulfonic acid, benzenesulfonic acid, and toluenesulfonic acid, and inorganic acids such as hydrofluoric acid, hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, perchloric acid, and phosphoric acid. The amount of the catalyst used is 1×10 -6 ~10 mol, preferably 1×10 -5 ~5 mol, more preferably 1×10 -4 ~1 mol with respect to 1 mol of the monomer.

[0071] When obtaining a thermally crosslinkable polysiloxane (Sx) by hydrolysis and condensation from these monomers, the amount of water is preferably 0.01 to 100 moles, more preferably 0.05 to 50 moles, and still more preferably 0.1 to 30 moles per mole of the hydrolyzable substituent bonded to the monomer. If it is 100 moles or less, the apparatus used for the reaction becomes smaller and more economical.

[0072] As an operation method, a monomer is added to an aqueous catalyst solution to initiate a hydrolysis and condensation reaction. At this time, an organic solvent may be added to the aqueous catalyst solution, the monomer may be diluted with an organic solvent, or both may be performed. The reaction temperature is 0 to 100 °C, preferably 5 to 80 °C. A method of maintaining the temperature at 5 to 80 °C during the dropping of the monomer and then aging at 20 to 80 °C is preferred.

[0073] Organic solvents that can be added to the aqueous catalyst solution or that can dilute the monomer include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, acetone, acetonitrile, tetrahydrofuran, toluene, hexane, ethyl acetate, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl amyl ketone, butanediol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, butanediol monoethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, t-butyl propionate, propylene glycol mono-t-butyl ether acetate, γ-butyrolactone, and mixtures thereof, etc. are preferred.

[0074] Among these solvents, preferred ones are water-soluble ones. For example, alcohols such as methanol, ethanol, 1-propanol, 2-propanol, polyhydric alcohols such as ethylene glycol, propylene glycol, polyhydric alcohol condensate derivatives such as butanediol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, butanediol monoethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, butanediol monopropyl ether, propylene glycol monopropyl ether, ethylene glycol monopropyl ether, acetone, acetonitrile, tetrahydrofuran and the like can be mentioned. Among these, particularly preferred are those having a boiling point of 100 ° C or lower.

[0075] In addition, the amount of the organic solvent used is preferably 0 to 1,000 ml, particularly 0 to 500 ml, per 1 mol of the monomer. When the amount of the organic solvent used is reduced, the reaction vessel becomes smaller and it is economical.

[0076] Thereafter, if necessary, a neutralization reaction of the catalyst is carried out to obtain an aqueous solution of the reaction mixture. At this time, the amount of the alkaline substance that can be used for neutralization is preferably 0.1 to 2 equivalents with respect to the acid used in the catalyst. This alkaline substance may be any substance as long as it shows alkalinity in water.

[0077] Subsequently, it is preferable to remove by-products such as alcohol generated by the hydrolysis condensation reaction from the reaction mixture by means of reduced pressure removal or the like. The temperature at which the reaction mixture is heated at this time depends on the types of the added organic solvent and the alcohol generated by the reaction, but is preferably 0 to 100 ° C, more preferably 10 to 90 ° C, still more preferably 15 to 80 ° C. Further, the degree of reduced pressure at this time varies depending on the types of the organic solvent and alcohol to be removed, the exhaust device, the condensation device, and the heating temperature, but is preferably below atmospheric pressure, more preferably 80 kPa or lower in absolute pressure, still more preferably 50 kPa or lower in absolute pressure. Although it is difficult to accurately know the amount of alcohol removed at this time, it is desirable that approximately 80% by mass or more of the generated alcohol or the like is removed.

[0078] Next, the acid catalyst used for hydrolysis condensation may be removed from the reaction mixture. As a method for removing the acid catalyst, water and the thermally crosslinkable polysiloxane solution are mixed, and the thermally crosslinkable polysiloxane is extracted with an organic solvent. The organic solvent used at this time is preferably one that can dissolve the thermally crosslinkable polysiloxane and separates into two layers when mixed with water. For example, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, acetone, tetrahydrofuran, toluene, hexane, ethyl acetate, cyclohexanone, methyl amyl ketone, butanediol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, butanediol monoethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, butanediol monopropyl ether, propylene glycol monopropyl ether, ethylene glycol monopropyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, t-butyl acetate, t-butyl propionate, propylene glycol mono-t-butyl ether acetate, γ-butyrolactone, methyl isobutyl ketone, cyclopentyl methyl ether, and mixtures thereof, etc. can be mentioned.

[0079] Furthermore, it is also possible to use a mixture of a water-soluble organic solvent and a water-insoluble organic solvent. For example, methanol-ethyl acetate mixture, ethanol-ethyl acetate mixture, 1-propanol-ethyl acetate mixture, 2-propanol-ethyl acetate mixture, butanediol monomethyl ether-ethyl acetate mixture, propylene glycol monomethyl ether-ethyl acetate mixture, ethylene glycol monomethyl ether-ethyl acetate mixture, butanediol monoethyl ether-ethyl acetate mixture, propylene glycol monoethyl ether-ethyl acetate mixture, ethylene glycol monoethyl ether-ethyl acetate mixture, butanediol monopropyl ether-ethyl acetate mixture, propylene glycol monopropyl ether-ethyl acetate mixture, ethylene glycol monopropyl ether-ethyl acetate mixture, methanol-methyl isobutyl ketone mixture, ethanol-methyl isobutyl ketone mixture, 1-propanol-methyl isobutyl ketone mixture, 2-propanol-methyl isobutyl ketone mixture, propylene glycol monomethyl ether-methyl isobutyl ketone mixture, ethylene glycol monomethyl ether-methyl isobutyl ketone mixture, propylene glycol monoethyl ether-methyl isobutyl ketone mixture, ethylene glycol monoethyl ether-methyl isobutyl ketone mixture, propylene glycol monopropyl ether-methyl isobutyl ketone mixture, ethylene glycol monopropyl ether-methyl isobutyl ketone mixture, methanol-cyclopentyl methyl ether mixture, ethanol-cyclopentyl methyl ether mixture, 1-propanol-cyclopentyl methyl ether mixture, 2-propanol-cyclopentyl methyl ether mixture, propylene glycol monomethyl ether-cyclopentyl methyl ether mixture, ethylene glycol monomethyl ether-cyclopentyl methyl ether mixture, propylene glycol monoethyl ether-cyclopentyl methyl ether mixture, ethylene glycol monoethyl ether-cyclopentyl methyl ether mixture, propylene glycol monopropyl ether-cyclopentyl methyl ether mixture, ethylene glycol monopropyl ether-cyclopentyl methyl ether mixture,Methanol-propylene glycol methyl ether acetate mixture, ethanol-propylene glycol methyl ether acetate mixture, 1-propanol-propylene glycol methyl ether acetate mixture, 2-propanol-propylene glycol methyl ether acetate mixture, propylene glycol monomethyl ether-propylene glycol methyl ether acetate mixture, ethylene glycol monomethyl ether-propylene glycol methyl ether acetate mixture, propylene glycol monoethyl ether-propylene glycol methyl ether acetate mixture, ethylene glycol monoethyl ether-propylene glycol methyl ether acetate mixture, propylene glycol monopropyl ether-propylene glycol methyl ether acetate mixture, ethylene glycol monopropyl ether-propylene glycol methyl ether acetate mixture, etc. are preferred, but the combinations are not limited thereto.

[0080] Incidentally, the mixing ratio of the water-soluble organic solvent and the water-insoluble organic solvent is appropriately selected. However, with respect to 100 parts by mass of the water-insoluble organic solvent, the water-soluble organic solvent is 0.1 to 1,000 parts by mass, preferably 1 to 500 parts by mass, and more preferably 2 to 100 parts by mass.

[0081] Subsequently, it may be washed with neutral water. As this water, what is usually called deionized water or ultrapure water may be used. The amount of this water is preferably 0.01 to 100 L, more preferably 0.05 to 50 L, and still more preferably 0.1 to 5 L with respect to 1 L of the thermally crosslinkable polysiloxane solution. As for the method of this washing, after putting both in the same container and stirring, it may be left to stand and the aqueous layer may be separated. The number of washing times may be 1 or more, but since washing more than 10 times does not necessarily result in the effect of just washing, it is preferably about 1 to 5 times.

[0082] As other methods for removing the acid catalyst, methods using ion exchange resins and methods of neutralizing with epoxy compounds such as ethylene oxide and propylene oxide and then removing can be mentioned. These methods can be appropriately selected according to the acid catalyst used in the reaction.

[0083] In the water washing operation at this time, a part of the thermally crosslinkable polysiloxane may escape into the aqueous layer, and in some cases, an effect equivalent to the fractionation operation may be obtained. Therefore, the number of water washing times and the amount of washing water may be appropriately selected in view of the catalyst removal effect and the fractionation effect.

[0084] In both the thermally crosslinkable polysiloxane solution in which the acid catalyst remains and the thermally crosslinkable polysiloxane solution from which the acid catalyst has been removed, the final solvent is added and the solvent is exchanged under reduced pressure to obtain a desired thermally crosslinkable polysiloxane solution. The temperature of the solvent exchange at this time depends on the type of reaction solvent and extraction solvent to be removed, but is preferably 0 to 100°C, more preferably 10 to 90°C, and still more preferably 15 to 80°C. Also, the degree of reduced pressure at this time varies depending on the type of extraction solvent to be removed, the exhaust device, the condensation device, and the heating temperature, but is preferably below atmospheric pressure, more preferably 80 kPa or less in absolute pressure, and still more preferably 50 kPa or less in absolute pressure.

[0085] At this time, the thermally crosslinkable polysiloxane may become unstable due to the change of the solvent. This is caused by the compatibility between the final solvent and the thermally crosslinkable polysiloxane. To prevent this, as a stabilizer, a monohydric or polyhydric alcohol having a cyclic ether described in paragraphs

[0181] to

[0182] of JP-A-2009-126940 as a substituent may be added. The amount to be added is 0 to 25 parts by mass, preferably 0 to 15 parts by mass, and more preferably 0 to 5 parts by mass with respect to 100 parts by mass of the thermally crosslinkable polysiloxane in the solution before the solvent exchange. However, when adding, 0.5 part by mass or more is preferable. If necessary, a monohydric or polyhydric alcohol having a cyclic ether as a substituent may be added to the solution before the solvent exchange to perform the solvent exchange operation.

[0086] When the thermosetting polysiloxane is concentrated above a certain concentration, the condensation reaction may further proceed, and it may change to a state where it is no longer soluble in the organic solvent. Therefore, it is preferably kept in a solution state with an appropriate concentration. Also, if it is too dilute, the amount of the solvent becomes excessive, so it is economically preferable to keep it in a solution state with an appropriate concentration. The concentration at this time is preferably 0.1 to 20% by mass.

[0087] The preferred final solvent to be added to the thermosetting polysiloxane solution is an alcohol-based solvent, and particularly preferred are monoalkyl ether derivatives such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, and butanediol. Specifically, butanediol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, butanediol monoethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, butanediol monopropyl ether, propylene glycol monopropyl ether, ethylene glycol monopropyl ether, diacetone alcohol, etc. are preferred.

[0088] If these solvents are the main components, it is also possible to add a non-alcohol-based solvent as an auxiliary solvent. Examples of this auxiliary solvent include acetone, tetrahydrofuran, toluene, hexane, ethyl acetate, cyclohexanone, methyl amyl ketone, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, t-butyl acetate, t-butyl propionate, propylene glycol mono-t-butyl ether acetate, γ-butyrolactone, methyl isobutyl ketone, cyclopentyl methyl ether, etc.

[0089] As another reaction operation using an acid catalyst, water or a water-containing organic solvent is added to a monomer or an organic solution of the monomer to initiate a hydrolysis reaction. At this time, the catalyst may be added to the monomer or the organic solution of the monomer, or may be added to the water or the water-containing organic solvent. The reaction temperature is 0 to 100°C, preferably 10 to 80°C. A method of heating to 10 to 50°C during the dropping of water and then raising the temperature to 20 to 80°C for aging is preferred.

[0090] When using an organic solvent, a water-soluble one is preferred, such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, acetone, tetrahydrofuran, acetonitrile, butanediol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, butanediol monoethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, butanediol monopropyl ether, propylene glycol monopropyl ether, ethylene glycol monopropyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether, and polyhydric alcohol condensate derivatives such as these and mixtures thereof.

[0091] The amount of the organic solvent used is preferably 0 to 1,000 ml, particularly 0 to 500 ml, per 1 mol of the monomer. The smaller the amount of the organic solvent used, the smaller the reaction vessel and the more economical. The post-treatment of the obtained reaction mixture is the same as the above method, and a thermally crosslinkable polysiloxane can be obtained.

[0092] (Synthesis Method 2: Alkali Catalyst) In addition, the thermally crosslinkable polysiloxane (Sx) can be produced by subjecting one or a mixture of two or more hydrolyzable monomers (Sm) to hydrolysis condensation in the presence of an alkali catalyst.

[0093] The alkali catalysts used at this time include methylamine, ethylamine, propylamine, butylamine, ethylenediamine, hexamethylenediamine, dimethylamine, diethylamine, ethylmethylamine, trimethylamine, triethylamine, tripropylamine, tributylamine, cyclohexylamine, dicyclohexylamine, monoethanolamine, diethanolamine, dimethylmonoethanolamine, monomethyldiethanolamine, triethanolamine, diazabicyclooctane, diazabicyclononene, diazabicycloundecene, hexamethylenetetramine, aniline, N,N-dimethylaniline, pyridine, N,N-dimethylaminopyridine, pyrrole, piperazine, pyrrolidine, piperidine, picoline, tetramethylammonium hydroxide, choline hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, ammonia, lithium hydroxide, sodium hydroxide, potassium hydroxide, barium hydroxide, calcium hydroxide, etc. The amount of the catalyst used is 1×10 -6 mol to 10 mol, preferably 1×10 -5 mol to 5 mol, more preferably 1×10 -4 mol to 1 mol.

[0094] When obtaining a thermally crosslinkable polysiloxane by hydrolysis and condensation from the above monomers, it is preferable to add 0.1 to 50 mol of water per 1 mol of the hydrolyzable substituent bonded to the monomer. If it is 50 mol or less, the apparatus used for the reaction becomes smaller and more economical.

[0095] As an operation method, the monomer is added to the aqueous catalyst solution to initiate the hydrolysis and condensation reaction. At this time, an organic solvent may be added to the aqueous catalyst solution, or the monomer may be diluted with an organic solvent, or both may be done. The reaction temperature is 0 to 100°C, preferably 5 to 80°C. A method of maintaining the temperature at 5 to 80°C during the dropping of the monomer and then aging at 20 to 80°C is preferable.

[0096] As the organic solvent that can be added to the aqueous alkali catalyst solution or can dilute the monomer, those similar to the organic solvents exemplified as those that can be added to the aqueous acid catalyst solution are preferably used. The amount of the organic solvent used is preferably 0 to 1,000 ml per mole of the monomer in order to carry out the reaction economically.

[0097] Thereafter, if necessary, a neutralization reaction of the catalyst is carried out to obtain an aqueous reaction mixture solution. At this time, the amount of the acidic substance that can be used for neutralization is preferably 0.1 to 2 equivalents relative to the alkaline substance used in the catalyst. This acidic substance may be any substance as long as it shows acidity in water.

[0098] Subsequently, it is preferable to remove by-products such as alcohol generated by the hydrolysis condensation reaction from the reaction mixture by means of reduced pressure removal or the like. The temperature at which the reaction mixture is heated depends on the types of the added organic solvent and the alcohol generated by the reaction, but is preferably 0 to 100 ° C, more preferably 10 to 90 ° C, and still more preferably 15 to 80 ° C. Also, the degree of reduced pressure at this time varies depending on the types of the organic solvent and alcohol to be removed, the exhaust device, the condensation device, and the heating temperature, but is preferably below atmospheric pressure, more preferably 80 kPa or less in absolute pressure, and still more preferably 50 kPa or less in absolute pressure. Although it is difficult to accurately know the amount of alcohol removed at this time, it is desirable that approximately 80 mass% or more of the generated alcohol is removed.

[0099] Next, in order to remove the alkali catalyst used in the hydrolysis condensation, the thermally crosslinkable polysiloxane is extracted with an organic solvent. As the organic solvent to be used at this time, those that can dissolve the thermally crosslinkable polysiloxane and separate into two layers when mixed with water are preferred. For example, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, acetone, tetrahydrofuran, toluene, hexane, ethyl acetate, cyclohexanone, methyl amyl ketone, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol monopropyl ether, ethylene glycol monopropyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, t-butyl acetate, t-butyl propionate, propylene glycol mono-t-butyl ether acetate, γ-butyrolactone, methyl isobutyl ketone, cyclopentyl methyl ether, and mixtures thereof, etc. can be mentioned.

[0100] Furthermore, it is also possible to use a mixture of a water-soluble organic solvent and a water-insoluble organic solvent.

[0101] Specific examples of the organic solvent used when removing the alkali catalyst can be the same as those specifically exemplified above for the organic solvents used when removing the acid catalyst, and mixtures of a water-soluble organic solvent and a water-insoluble organic solvent.

[0102] The mixing ratio of the water-soluble organic solvent and the water-insoluble organic solvent is appropriately selected. However, it is 0.1 to 1,000 parts by mass, preferably 1 to 500 parts by mass, and more preferably 2 to 100 parts by mass of the water-soluble organic solvent with respect to 100 parts by mass of the water-insoluble organic solvent.

[0103] Subsequently, wash with neutral water. As this water, what is usually called deionized water or ultrapure water may be used. The amount of this water is 0.01 to 100 L, preferably 0.05 to 50 L, more preferably 0.1 to 5 L, per 1 L of the thermally crosslinkable polysiloxane solution. As for the method of this washing, both may be put in the same container, stirred, and then left to stand to separate the aqueous layer. The number of washing times may be one or more, but even if washed 10 times or more, the effect of just washing may not always be obtained. Therefore, it is preferably about 1 to 5 times.

[0104] Add the final solvent to the washed thermally crosslinkable polysiloxane solution and perform solvent exchange under reduced pressure to obtain the desired thermally crosslinkable polysiloxane solution. The temperature of the solvent exchange at this time depends on the type of extraction solvent to be removed, but is preferably 0 to 100°C, more preferably 10 to 90°C, still more preferably 15 to 80°C. Also, the degree of reduced pressure at this time varies depending on the type of extraction solvent to be removed, the exhaust device, the condensation device, and the heating temperature, but is preferably below atmospheric pressure, more preferably 80 kPa or less in absolute pressure, still more preferably 50 kPa or less in absolute pressure.

[0105] A preferable final solvent to be added to the thermally crosslinkable polysiloxane solution is an alcohol-based solvent, and particularly preferable ones are monoalkyl ethers such as ethylene glycol, diethylene glycol, and triethylene glycol, and monoalkyl ethers such as propylene glycol and dipropylene glycol. Specifically, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol monopropyl ether, ethylene glycol monopropyl ether, diacetone alcohol, etc. are preferable.

[0106] As another reaction operation using an alkali catalyst, water or a water-containing organic solvent is added to a monomer or an organic solution of the monomer to initiate a hydrolysis reaction. At this time, the catalyst may be added to the monomer or the organic solution of the monomer, or may be added to the water or the water-containing organic solvent. The reaction temperature is 0 to 100°C, preferably 10 to 80°C. A method of heating to 10 to 50°C when dropping water and then raising the temperature to 20 to 80°C for aging is preferred.

[0107] As the organic solvent that can be used as the organic solution of the monomer or the water-containing organic solvent, water-soluble ones are preferred, such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, acetone, tetrahydrofuran, acetonitrile, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol monopropyl ether, ethylene glycol monopropyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether, and polyhydric alcohol condensate derivatives such as these and mixtures thereof.

[0108] The molecular weight of the thermally crosslinkable polysiloxane obtained by the above synthesis method 1 or 2 can be adjusted by controlling the reaction conditions during polymerization as well as by the selection of the monomer. However, it is preferred to use those having a weight average molecular weight of 100,000 or less, more preferably 200 to 50,000, and still more preferably 300 to 30,000. If the weight average molecular weight is 100,000 or less, the generation of foreign substances and coating spots will not occur. The data regarding the above weight average molecular weight is represented by the molecular weight in terms of polystyrene using gel permeation chromatography (GPC) with RI as the detector and tetrahydrofuran as the elution solvent, using polystyrene as the standard substance.

[0109] The physical properties of the thermally crosslinkable polysiloxane used in the present invention vary depending on the type of acid or alkali catalyst used during hydrolysis and condensation and the reaction conditions. Therefore, it can be appropriately selected according to the performance of the target metal-containing film.

[0110] Furthermore, a polysiloxane derivative produced by using a mixture of one or more hydrolyzable monomers (Sm) and a hydrolyzable metal compound represented by the following general formula (Mm) under the conditions using the above-mentioned acid or alkali catalyst can be used as a component of the composition for forming a metal-containing film.

Chemical formula

[0111] Examples of the hydrolyzable metal compound represented by the above general formula (Mm) include certain metal alkoxides such as boron, aluminum, gallium, yttrium, germanium, titanium, and hafnium. Specifically, those described in

[0107] to

[0123] of the pamphlet of JP-A-2020-118960 can be used.

[0112] <Polycarbosilane (Sy)> The polycarbosilane preferably contains a repeating unit represented by the following general formula (Sy-1).

Chemical formula

[0113] Examples of Z in the general formula (Sy-1) include substituted or unsubstituted divalent chain hydrocarbon groups having 1 to 20 carbon atoms, substituted or unsubstituted divalent aliphatic cyclic hydrocarbon groups having 3 to 20 carbon atoms, and substituted or unsubstituted divalent aromatic hydrocarbon groups having 6 to 20 carbon atoms. In the present specification, the chain hydrocarbon group includes both a straight-chain hydrocarbon group and a branched-chain hydrocarbon group.

[0114] Examples of the unsubstituted divalent chain hydrocarbon group having 1 to 20 carbon atoms include chain saturated hydrocarbon groups such as a methanediyl group and an ethanediyl group, and chain unsaturated hydrocarbon groups such as an ethenediyl group and a propenediyl group.

[0115] Examples of the unsubstituted divalent aliphatic cyclic hydrocarbon group having 3 to 20 carbon atoms include monocyclic saturated hydrocarbon groups such as a cyclobutanediyl group, monocyclic unsaturated hydrocarbon groups such as a cyclobutenediyl group, polycyclic saturated hydrocarbon groups such as a bicyclo[2.2.1]heptanediyl group, and polycyclic unsaturated hydrocarbon groups such as a bicyclo[2.2.1]heptenediyl group.

[0116] Examples of the unsubstituted divalent aromatic hydrocarbon group having 6 to 20 carbon atoms include a phenylene group, a biphenylene group, a phenyleneethylene group, and a naphthylene group.

[0117] Examples of the substituent in the substituted divalent chain hydrocarbon group having 1 to 20 carbon atoms, substituted divalent aliphatic cyclic hydrocarbon group having 3 to 20 carbon atoms, and substituted divalent aromatic hydrocarbon group having 6 to 20 carbon atoms represented by Z include a halogen atom, a hydroxy group, a cyano group, a nitro group, an alkoxy group, an acyl group, and an acyloxy group.

[0118] Z is preferably an unsubstituted chain saturated hydrocarbon group, more preferably a methanediyl group or an ethanediyl group.

[0119] R in the above formula (Sy-1) d or R eExamples of the monovalent organic group having 1 to 30 carbon atoms represented by include a monovalent hydrocarbon group having 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms, a monovalent group (α) having a divalent heteroatom-containing group between carbon-carbon atoms of the hydrocarbon group, and a monovalent group (β) in which some or all of the hydrogen atoms of the monovalent group (α) having the hydrocarbon group or the divalent heteroatom-containing group are substituted with a monovalent heteroatom-containing group.

[0120] Examples of the monovalent hydrocarbon group having 1 to 30 carbon atoms include a monovalent linear hydrocarbon group having 1 to 30 carbon atoms, preferably 1 to 20 carbon atoms, a monovalent alicyclic hydrocarbon group having 3 to 30 carbon atoms, preferably 3 to 20 carbon atoms, and a monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms, preferably 6 to 20 carbon atoms.

[0121] Examples of the monovalent linear hydrocarbon group having 1 to 30 carbon atoms include an alkyl group such as a methyl group or an ethyl group, an alkenyl group such as an ethenyl group, and an alkynyl group such as an ethynyl group.

[0122] Examples of the monovalent alicyclic hydrocarbon group having 3 to 30 carbon atoms include a monovalent monocyclic alicyclic saturated hydrocarbon group such as a cyclopentyl group or a cyclohexyl group, a monovalent monocyclic alicyclic unsaturated hydrocarbon group such as a cyclopentenyl group or a cyclohexenyl group, a monovalent polycyclic alicyclic saturated hydrocarbon group such as a norbornyl group or an adamantyl group, and a monovalent polycyclic alicyclic unsaturated hydrocarbon group such as a norbornenyl group or a tricyclodecenyl group.

[0123] Examples of the monovalent aromatic hydrocarbon group having 6 to 30 carbon atoms include an aryl group such as a phenyl group, a tolyl group, a xylyl group, a naphthyl group, a methylnaphthyl group, or an anthryl group, and an aralkyl group such as a benzyl group, a naphthylmethyl group, or an anthrylmethyl group.

[0124] Examples of the heteroatom constituting the divalent or monovalent heteroatom-containing group include an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, a silicon atom, a halogen atom, etc. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.

[0125] Examples of the divalent heteroatom-containing group include -O-, -CO-, -S-, -CS-, -NR'-, and groups formed by combining two or more of these. R' is a hydrogen atom or a monovalent hydrocarbon group.

[0126] Examples of the monovalent heteroatom-containing group include halogen atoms such as a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, a hydroxy group, a carboxy group, a cyano group, an amino group, a sulfanyl group, and the like.

[0127] R d or R e As the monovalent organic group represented by, a monovalent hydrocarbon group is preferable, a monovalent chain hydrocarbon group and a monovalent aromatic hydrocarbon group are more preferable, and an alkyl group and an aryl group are even more preferable.

[0128] R d or R e The number of carbon atoms of the monovalent organic group represented by is preferably 1 or more and 10 or less, and more preferably 1 or more and 6 or less.

[0129] R d or R e Examples of the halogen atom represented by include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like. As this halogen atom, a chlorine atom or a bromine atom is preferable.

[0130] The lower limit of the content ratio of the structural unit (Sy-1) to all the structural units constituting the polycarbosilane (Sy) is preferably 5 mol%, more preferably 30 mol%, even more preferably 60 mol%, and particularly preferably 80 mol%. On the other hand, the upper limit of the content ratio of the structural unit (Sy-1) is not particularly limited and may be 100 mol%. By setting the content ratio of the structural unit (Sy-1) within the above range, the resist pattern collapse inhibitory property, oxygen-based gas etching resistance, and solvent resistance of the metal-containing film formed by the metal-containing film-forming composition of the present invention can be further improved.

[0131] The polycarbosilane (Sy) may contain repeating units represented by the following formula (Sy-2) and / or the following general formula (Sy-3) in addition to the repeating units represented by the above general formula (Sy-1).

[0132]

Chemical formula

[0133] When the polycarbosilane (Sy) has a repeating unit represented by the above formula (Sy-2), the lower limit of the content ratio of the structural unit (Sy-2) to all the structural units constituting the polycarbosilane (Sy) is preferably 0.1 mol%, more preferably 1 mol%, and even more preferably 5 mol%. On the other hand, the upper limit of the content ratio of the structural unit (Sy-2) is preferably 50 mol%, more preferably 40 mol%, even more preferably 30 mol%, and particularly preferably 20 mol%.

[0134]

Chemical formula

[0135] In the above general formula (Sy-3), R f is a monovalent hydrocarbon group having 1 to 20 carbon atoms, which may be substituted or unsubstituted. c is 1 or 2. When c is 2, the two R f may be the same as or different from each other.

[0136] As the above c, 1 is preferable.

[0137] Examples of R f include the same groups as the monovalent hydrocarbon groups having 1 to 20 carbon atoms exemplified in R d or R e in the above general formula (Sy-1). In addition, examples of the substituents of the monovalent hydrocarbon groups having 1 to 20 carbon atoms include the same groups as the monovalent heteroatom-containing groups exemplified in R d or R e in the above general formula (Sy-1).

[0138] Rf As for this, a substituted or unsubstituted monovalent chain hydrocarbon group or a substituted or unsubstituted monovalent aromatic hydrocarbon group is preferable, an alkyl group or an aryl group is more preferable, and a methyl group or a phenyl group is even more preferable.

[0139] When the polycarbosilane (Sy) has the structural unit (Sy-3), the lower limit of the content ratio of the structural unit (Sy-3) to all the structural units constituting the polycarbosilane (Sy) is preferably 0.1 mol%, more preferably 1 mol%, and even more preferably 5 mol%. The upper limit of the content ratio of the structural unit (Sy-3) is preferably 50 mol%, more preferably 40 mol%, even more preferably 30 mol%, and particularly preferably 20 mol%.

[0140] In addition to the above structural units, the polycarbosilane (Sy) may also contain a structural unit containing a Si—O—Si structure formed by dehydration condensation or the like from the hydroxy group represented by R d or R e in the above general formula (Sy-1).

[0141] Preferred solvents for the polycarbosilane are alcohol solvents or ether solvents. Particularly preferred alcohol solvents are ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, diacetone alcohol, etc. Specific examples of ether solvents preferably include propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol monopropyl ether, ethylene glycol monopropyl ether, etc.

[0142] In addition, commercially available polycarbosilanes can be used in the present invention. For example, polycarbosilanes having a unit structure represented by the following formula (Sy-4) (for example, manufactured by NGS Advanced Fibers Co., Ltd., trade name NIPSY TypeS (Mn = 2,716 (GPC UV detector / polystyrene conversion)), trade name NIPSY TypeL (number average molecular weight 1,000, weight average molecular weight 4,500), etc.) can be used. The weight average molecular weight of the polycarbosilane used in the present invention is preferably 400 to 12,000, more preferably 2,000 to 12,000.

[0143]

Chemical formula

[0144] (Polysilane (Sz)) The polysilane preferably contains a repeating unit represented by the following general formula (Sz-1). (R 9 R 10 R 11 Si) a2 (R 12 R 13 Si) a3 (R 14 Si) a4 (Si) a5 (Sz-1) (In the formula, R 9 、R 10 、R 11 、R 12 、R 13 、and R 14 are each a methyl group, a phenyl group, or a hydroxyl group. a2, a3, a4, and a5 are molar fractions, and a2 + a3 + a4 + a5 = 1, 0 ≤ a2 ≤ 1, 0 ≤ a3 ≤ 1, 0 ≤ a4 ≤ 1, 0 ≤ a5 ≤ 1. )

[0145] Furthermore, it may be one or more polymers selected from hydrolyzates, condensates, and hydrolytic condensates of the above polysilane compound. It may also be a hydrolyzate, condensate, or hydrolytic condensate with polysiloxane, or may be hydrolytically condensed with a hydrolyzable monomer (Sm).

[0146] As the polysilane compound represented by the general formula (Sz-1), for example, Ogsoal SI-10-10 (polymethylphenylsilane), SI-10-20 (polymethylphenylsilane), SI-20-10 (polyphenylsilane), SI-20-10 modified (polyphenylsilane), SI-30-10 (cyclic polydiphenylsilane), etc. manufactured by Osaka Gas Chemical Co., Ltd. can be used. Further, those obtained by reacting these under alkaline conditions to reduce the molecular weight may also be used.

[0147] In particular, it is preferable that the weight average molecular weight of the polysilane compound represented by the general formula (Sz-1) is 1,000 or less. By setting the weight average molecular weight to 1,000 or less, the hydrolyzate, condensate, or hydrolytic condensate of the mixture containing the polysilane compound represented by the general formula (Sz-1) is likely to dissolve in the solvent component of the composition for forming a metal-containing film, and the generation of particles during film formation can be prevented.

[0148] Here, various solvents can be used as the solvent used in the reaction under the above alkaline conditions. For example, hydrocarbon solvents such as benzene, toluene, and xylene, glycol solvents such as propylene glycol monomethyl ether and propylene glycol monoethyl ether, ether solvents such as diethyl ether, diisopropyl ether, dibutyl ether, tetrahydrofuran, and 1,4-dioxane, ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl amyl ketone, cyclopentanone, and cyclohexanone, and alcohol solvents such as ethanol, isopropyl alcohol, and butanol. One or more selected from these can be used.

[0149] Also, various bases can be used for addition. For example, inorganic bases such as sodium hydroxide, potassium hydroxide, barium hydroxide, ammonia, tetramethylammonium hydroxide, sodium carbonate, sodium hydrogen carbonate, potassium carbonate, lithium hydride, sodium hydride, potassium hydride, calcium hydride, etc., alkyl metals such as methyl lithium, n-butyl lithium, methyl magnesium chloride, ethyl magnesium bromide, etc., alkoxides such as sodium methoxide, sodium ethoxide, potassium t-butoxide, etc., and organic bases such as triethylamine, diisopropylethylamine, N,N-dimethylaniline, pyridine, 4-dimethylaminopyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) can be used. The reaction temperature is preferably from -50°C to about the boiling point of the solvent, more preferably from room temperature to 100°C.

[0150] The hydrolysis, condensation, or hydrolysis-condensation reaction can be carried out using one or more compounds selected from inorganic acids, aliphatic sulfonic acids, and aromatic sulfonic acids as an acid catalyst. Examples of the acid catalyst used at this time include hydrofluoric acid, hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, perchloric acid, phosphoric acid, methanesulfonic acid, benzenesulfonic acid, toluenesulfonic acid, etc. The amount of the catalyst used is preferably 10 -6 to 10 moles, more preferably 10 -5 to 5 moles, and even more preferably 10 -4 to 1 mole per mole of the monomer (polysilane compound).

[0151] When synthesizing a polymer by hydrolytic condensation of these monomers, the amount of water is preferably 0.01 to 100 moles, more preferably 0.05 to 50 moles, and even more preferably 0.1 to 30 moles per mole of the hydrolyzable substituent bonded to the monomer. By setting the addition amount to 100 moles or less, the equipment used for the reaction does not become excessive, which is economical. Also, if the addition amount is 0.01 mole or more, the reaction proceeds.

[0152] As an operation method, a monomer can be added to an aqueous catalyst solution to initiate a hydrolysis condensation reaction. At this time, an organic solvent may be added to the aqueous catalyst solution, or the monomer may be diluted with an organic solvent, or both may be performed. The reaction temperature is preferably 0 to 100 °C, more preferably 5 to 80 °C. A method of maintaining the temperature at 5 to 80 °C during the dropping of the monomer and then aging at 20 to 80 °C is preferred.

[0153] Examples of the organic solvent that can be added to the aqueous catalyst solution or can dilute the monomer include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, acetone, acetonitrile, tetrahydrofuran, toluene, hexane, ethyl acetate, cyclohexanone, methyl amyl ketone, butanediol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, butanediol monoethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, propylene glycol mono-t-butyl ether acetate, γ-butyrolactone, and mixtures thereof are preferred.

[0154] Among these solvents, the more preferred ones are water-soluble ones. For example, alcohols such as methanol, ethanol, 1-propanol, 2-propanol, polyhydric alcohols such as ethylene glycol, propylene glycol, polyhydric alcohol condensate derivatives such as butanediol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, butanediol monoethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, butanediol monopropyl ether, propylene glycol monopropyl ether, ethylene glycol monopropyl ether, acetone, acetonitrile, tetrahydrofuran, etc. can be mentioned. Among these, those with a boiling point of 100 °C or lower are particularly preferred.

[0155] In addition, the amount of the organic solvent used is preferably 0 to 1,000 mL, particularly preferably 0 to 500 mL, per 1 mol of the monomer. If the amount of the organic solvent used is 1,000 mL or less, the reaction vessel will not become too large, which is economical.

[0156] Thereafter, if necessary, a neutralization reaction of the catalyst is carried out, the alcohol produced by the hydrolysis condensation reaction is removed under reduced pressure, and an aqueous solution of the reaction mixture is obtained. At this time, the amount of the basic substance that can be used for neutralization is preferably 0.1 to 2 equivalents relative to the acid used in the catalyst. Any substance may be used as long as it shows alkalinity in water.

[0157] Subsequently, it is preferable to remove by-products such as alcohol generated by the hydrolysis condensation reaction from the reaction mixture. At this time, the temperature for heating the reaction mixture depends on the types of the added organic solvent and alcohol generated by the reaction, but is preferably 0 to 100 °C, more preferably 10 to 90 °C, and still more preferably 15 to 80 °C. Further, the degree of reduced pressure at this time varies depending on the types of the organic solvent and alcohol to be removed, the exhaust device, the condensation device, and the heating temperature, but is preferably below atmospheric pressure, more preferably 80 kPa or less in absolute pressure, and still more preferably 50 kPa or less in absolute pressure. Although it is difficult to accurately know the amount of alcohol removed at this time, it is desirable that approximately 80% by mass or more of the generated alcohol or the like is removed.

[0158] Next, the acid catalyst used for hydrolysis condensation may be removed from the reaction mixture. As a method for removing the acid catalyst, water and the polymer are mixed, and the polymer is extracted with an organic solvent. The organic solvent used at this time is preferably one that can dissolve the polymer and separates into two layers when mixed with water. For example, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, acetone, tetrahydrofuran, toluene, hexane, ethyl acetate, cyclohexanone, methyl amyl ketone, butanediol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, butanediol monoethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, butanediol monopropyl ether, propylene glycol monopropyl ether, ethylene glycol monopropyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, propylene glycol mono-t-butyl ether acetate, γ-butyrolactone, methyl isobutyl ketone, cyclopentyl methyl ether, etc., and mixtures thereof can be mentioned.

[0159] Furthermore, it is also possible to use a mixture of a water-soluble organic solvent and a water-insoluble organic solvent. For example, methanol + ethyl acetate, ethanol + ethyl acetate, 1-propanol + ethyl acetate, 2-propanol + ethyl acetate, butanediol monomethyl ether + ethyl acetate, propylene glycol monomethyl ether + ethyl acetate, ethylene glycol monomethyl ether + ethyl acetate, butanediol monoethyl ether + ethyl acetate, propylene glycol monoethyl ether + ethyl acetate, ethylene glycol monoethyl ether + ethyl acetate, butanediol monopropyl ether + ethyl acetate, propylene glycol monopropyl ether + ethyl acetate, ethylene glycol monopropyl ether + ethyl acetate, methanol + methyl isobutyl ketone, ethanol + methyl isobutyl ketone, 1-propanol + methyl isobutyl ketone, 2-propanol + methyl isobutyl ketone, propylene glycol monomethyl ether + methyl isobutyl ketone, ethylene glycol monomethyl ether + methyl isobutyl ketone, propylene glycol monoethyl ether + methyl isobutyl ketone, ethylene glycol monoethyl ether + methyl isobutyl ketone, propylene glycol monopropyl ether + methyl isobutyl ketone, ethylene glycol monopropyl ether + methyl isobutyl ketone, methanol + cyclopentyl methyl ether, ethanol + cyclopentyl methyl ether, 1-propanol + cyclopentyl methyl ether, 2-propanol + cyclopentyl methyl ether, propylene glycol monomethyl ether + cyclopentyl methyl ether, ethylene glycol monomethyl ether + cyclopentyl methyl ether, propylene glycol monoethyl ether + cyclopentyl methyl ether, ethylene glycol monoethyl ether + cyclopentyl methyl ether, propylene glycol monopropyl ether + cyclopentyl methyl ether, ethylene glycol monopropyl ether + cyclopentyl methyl ether, methanol + propylene glycol methyl ether acetate, ethanol + propylene glycol methyl ether acetate, 1-propanol + propylene glycol methyl ether acetate,2-Propanol + propylene glycol methyl ether acetate, propylene glycol monomethyl ether + propylene glycol methyl ether acetate, ethylene glycol monomethyl ether + propylene glycol methyl ether acetate, propylene glycol monoethyl ether + propylene glycol methyl ether acetate, ethylene glycol monoethyl ether + propylene glycol methyl ether acetate, propylene glycol monopropyl ether + propylene glycol methyl ether acetate, ethylene glycol monopropyl ether + propylene glycol methyl ether acetate, etc. are preferred, but the combination is not limited thereto.

[0160] In addition, the mixing ratio of the water-soluble organic solvent and the water-insoluble organic solvent is appropriately selected. However, with respect to 100 parts by mass of the water-insoluble organic solvent, 0.1 to 1,000 parts by mass of the water-soluble organic solvent is preferred, more preferably 1 to 500 parts by mass, and even more preferably 2 to 100 parts by mass.

[0161] Subsequently, it may be washed with neutral water. As this water, what is usually called deionized water or ultrapure water may be used. The amount of this water is preferably 0.01 to 100 L, more preferably 0.05 to 50 L, and even more preferably 0.1 to 5 L with respect to 1 L of the polymer solution. For this washing method, after putting both in the same container and stirring, it may be left to stand and the aqueous layer may be separated. The number of washing times may be 1 or more, but since no effect of just washing can be obtained even if washed 10 or more times, it is preferably about 1 to 5 times.

[0162] At this time, due to the water washing operation, a part of the polymer escapes into the aqueous layer, and in some cases, an effect substantially equivalent to the fractionation operation is obtained. Therefore, the number of water washing times and the amount of washing water may be appropriately selected in view of the catalyst removal effect and the fractionation effect.

[0163] As other methods for removing the acid catalyst, methods using ion exchange resins and methods of removing the acid catalyst after neutralizing it with an epoxy compound such as ethylene oxide or propylene oxide can be mentioned. These methods can be appropriately selected according to the acid catalyst used in the reaction.

[0164] In both the case of the polymer with the residual acid catalyst and the polymer solution with the removed acid catalyst, a final solvent is added and the solvent is exchanged under reduced pressure to obtain a polymer solution. The temperature of the solvent exchange at this time depends on the type of reaction solvent or extraction solvent to be removed, but is preferably 0 to 100 °C, more preferably 10 to 90 °C, and even more preferably 15 to 80 °C. Also, the degree of reduced pressure at this time varies depending on the type of extraction solvent to be removed, the exhaust device, the condensation device, and the heating temperature, but is preferably below atmospheric pressure, more preferably 80 kPa or less in absolute pressure, and even more preferably 50 kPa or less in absolute pressure.

[0165] At this time, the polymer may become unstable due to the change of the solvent. This is caused by the compatibility between the final solvent and the polymer. To prevent this, a monohydric or polyhydric alcohol having a cyclic ether as a substituent or an ether compound may be added as a stabilizer. The amount to be added is preferably 0 to 25 parts by mass, more preferably 0 to 15 parts by mass, and even more preferably 0 to 5 parts by mass with respect to 100 parts by mass of the polymer in the solution before the solvent exchange. However, when adding, 0.5 parts by mass or more is preferable. If necessary, a stabilizer may be added to the solution before the solvent exchange and the solvent exchange operation may be performed.

[0166] Also, the concentration of the polymer is preferably 0.1 to 20% by mass. By setting the concentration in this way, the condensation reaction of the polymer proceeds and it does not change to a state where it is insoluble in the organic solvent again. Also, by setting the concentration in this way, the amount of the solvent is appropriate, which is economical.

[0167] The preferred final solvent to be added to the polymer is an alcohol-based solvent, and particularly preferred are monoalkyl ether derivatives such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, butanediol, etc. Specifically, butanediol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, butanediol monoethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, butanediol monopropyl ether, propylene glycol monopropyl ether, ethylene glycol monopropyl ether, etc. are preferred.

[0168] If these solvents are the main components, it is also possible to add a non-alcohol-based solvent as an auxiliary solvent. Examples of this auxiliary solvent include acetone, tetrahydrofuran, toluene, hexane, ethyl acetate, cyclohexanone, methyl amyl ketone, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, t-butyl acetate, t-butyl propionate, propylene glycol mono-t-butyl ether acetate, γ-butyrolactone, methyl isobutyl ketone, cyclopentyl methyl ether, etc.

[0169] Also, as another reaction operation, water or a water-containing organic solvent may be added to the monomer or the organic solution of the monomer to initiate a hydrolysis reaction. At this time, the acid catalyst may be added to the monomer or the organic solution of the monomer, or may be added to the water or the water-containing organic solvent. The reaction temperature is preferably 0 to 100 °C, more preferably 10 to 80 °C. A method of heating to 10 to 50 °C during the dropwise addition of water and then raising the temperature to 20 to 80 °C for aging is preferred.

[0170] When using an organic solvent, a water-soluble one is preferred. Specifically, examples include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, acetone, tetrahydrofuran, acetonitrile, butanediol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, butanediol monoethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, butanediol monopropyl ether, propylene glycol monopropyl ether, ethylene glycol monopropyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether, and other polyhydric alcohol condensate derivatives and mixtures thereof.

[0171] At this time, the amount of the organic solvent used may be the same as the above amount. The obtained reaction mixture can be post-treated in the same manner as above to obtain a polymer.

[0172] In addition, the hydrolysis, condensation, or hydrolysis-condensation reaction for synthesizing the polymer can also be carried out using a basic catalyst. The basic catalysts used at this time include methylamine, ethylamine, propylamine, butylamine, ethylenediamine, hexamethylenediamine, dimethylamine, diethylamine, ethylmethylamine, trimethylamine, triethylamine, tripropylamine, tributylamine, cyclohexylamine, dicyclohexylamine, monoethanolamine, diethanolamine, dimethylmonoethanolamine, monomethyldiethanolamine, triethanolamine, diazabicyclooctane, diazabicyclononene, diazabicycloundecene, hexamethylenetetramine, aniline, N,N-dimethylaniline, pyridine, N,N-dimethylaminopyridine, pyrrole, piperazine, pyrrolidine, piperidine, picoline, tetramethylammonium hydroxide, choline hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, ammonia, lithium hydroxide, sodium hydroxide, potassium hydroxide, barium hydroxide, calcium hydroxide, and the like. The amount of the catalyst used may be the same as that when using the above acid catalyst.

[0173] When obtaining the polymer from these monomers, it is preferable to add 0.1 to 50 moles of water per mole of the hydrolyzable substituent bonded to the monomer. By setting the addition amount to 50 moles or less, the apparatus used for the reaction does not become excessive, which is economical. If the addition amount is 0.1 mole or more, the reaction proceeds.

[0174] The operation method of the reaction may be the same as that when using the above acid catalyst.

[0175] The organic solvent that can be added to the catalyst aqueous solution or that can dilute the monomer is preferably the same as that when using the above acid catalyst. The amount of the organic solvent used is preferably 0 to 1,000 mL per mole of the monomer. By setting the amount in this way, the reaction vessel does not become excessive, which is economical.

[0176] Thereafter, if necessary, a neutralization reaction of the catalyst is carried out, and the alcohol produced by the hydrolysis condensation reaction is removed under reduced pressure to obtain an aqueous solution of the reaction mixture. At this time, the amount of the acidic substance that can be used for neutralization is preferably 0.1 to 2 equivalents relative to the basic substance used in the catalyst. Any substance may be used as long as it shows acidity in water.

[0177] Subsequently, it is preferable to remove by-products such as alcohol produced by the hydrolysis condensation reaction from the reaction mixture. At this time, the temperature and degree of reduced pressure for heating the reaction mixture may be the same as those when using the above acid catalyst.

[0178] Next, the basic catalyst used for the hydrolysis condensation may be removed from the reaction mixture. As the organic solvent used for removing the basic catalyst, the same one as that used when using the above acid catalyst can be used. Also, the basic catalyst can be removed using a mixture of the same water-soluble organic solvent and water-insoluble organic solvent as that used when using the above acid catalyst. In addition, the mixing ratio of the water-soluble organic solvent and the water-insoluble organic solvent may be the same as that when using the above acid catalyst.

[0179] Subsequently, it may be washed with neutral water. The washing method may be the same as that when using the above acid catalyst.

[0180] A final solvent is added to the washed polymer, and the solvent is exchanged under reduced pressure to obtain a polymer solution. The temperature and degree of reduced pressure for the solvent exchange may be the same as those when using the above acid catalyst.

[0181] Also, at this time, similar to when using the above acid catalyst, a monohydric or polyhydric alcohol having a cyclic ether as a substituent, or an ether compound may be added as a stabilizer. Also, the polymer solution is preferably adjusted to a concentration of 0.1 to 20% by mass.

[0182] Preferred final solvents to be added to the polymer are alcohol solvents or ether solvents. Particularly preferred alcohol solvents are ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, etc. Specific examples of ether solvents preferably include propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol monopropyl ether, ethylene glycol monopropyl ether, etc.

[0183] If these solvents are the main components, it is also possible to add a non-alcohol solvent as an auxiliary solvent. As this auxiliary solvent, the same auxiliary solvents as those used when using the above acid catalyst can be used.

[0184] Also, as another reaction operation, water or a water-containing organic solvent may be added to the monomer or the organic solution of the monomer to initiate a hydrolysis reaction. At this time, the basic catalyst may be added to the monomer or the organic solution of the monomer, or may be added to the water or the water-containing organic solvent. The reaction temperature is preferably 0 to 100°C, more preferably 10 to 80°C. A method of heating to 10 to 50°C during the dropping of water and then raising the temperature to 20 to 80°C for aging is preferred.

[0185] When using an organic solvent, a water-soluble one is preferred. Specifically, examples include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, acetone, tetrahydrofuran, acetonitrile, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol monopropyl ether, ethylene glycol monopropyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether, and polyhydric alcohol condensate derivatives such as these and mixtures thereof.

[0186] At this time, the amount of the organic solvent used may be the same as the above amount. The obtained reaction mixture can be post-treated in the same manner as above to obtain a polymer.

[0187] The molecular weight of the polymer obtained by the reaction as described above can be adjusted not only by the selection of the monomer but also by controlling the reaction conditions during polymerization. The molecular weight of the obtained polymer is not particularly limited, but those having a weight average molecular weight of 100,000 or less are preferred, more preferably 200 to 50,000, and even more preferably 300 to 30,000. By using those having a weight average molecular weight of 100,000 or less, the generation of foreign substances and coating irregularities can be suppressed. The data regarding the above weight average molecular weight is represented in terms of polystyrene equivalent molecular weight by gel permeation chromatography (GPC) using RI as the detector and tetrahydrofuran as the elution solvent, with polystyrene used as the standard substance.

[0188] The content ratio of the (A) silicon-containing polymer in the composition for forming a metal-containing film of the present invention is not particularly limited. For example, it can be 0.1 to 20 parts by mass, preferably 0.2 to 5 parts by mass, more preferably 0.5 to 2 parts by mass with respect to 100 parts by mass of the (C) organic solvent.

[0189] <(B) metal source> The (B) metal source contained in the composition for forming a metal-containing film of the present invention is a salt of a metal selected from Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi and a C1-C30, preferably C1-C20, monovalent to tetravalent carboxylic acid, or a complex of the metal and β-diketones.

[0190] Preferred carboxylates can be exemplified as follows.

[0191]

Chemical formula

[0192] The carboxylate ions for forming the carboxylate in the above general formula are specifically exemplified as follows.

[0193]

Chemical formula

[0194]

Chemical formula

[0195]

Chemical formula

[0196]

Chemical formula

[0197]

Chemical formula

[0198]

Chemical formula

[0199]

Chemical formula

[0200]

Chemical formula

[0201] [Chemistry]

[0202] [Chemistry]

[0203] [Chemistry]

[0204] The carboxylic acid ions for forming the above carboxylate become more soluble in the organic solvent as the number of carbon atoms in the carboxylic acid increases, which is preferable. Also, if the number of carbon atoms in the carboxylic acid is not too large, the shrinkage amount when forming the resist film decreases, and the outgas component amount also decreases. From the above viewpoints, the carboxylic acid ions preferably have a linear or branched alkyl group having 3 to 10 carbon atoms.

[0205] Preferred β-diketone complexes can be exemplified as follows.

[0206] [Chemistry] (In the formula, R 1 , R 2 are the same or different linear, branched or cyclic alkyl groups having 1 to 20 carbon atoms, alkenyl groups having 2 to 20 carbon atoms, alkynyl groups having 2 to 20 carbon atoms, or aryl groups having 6 to 20 carbon atoms, and these may have a hydroxy group, an alkoxy group, an ether group, an ester group, an amino group, an amide group, a sulfonic acid ester group, a halogen atom, a cyano group, a nitro group, a carbonate group, a carbamate group, a thiol group, a sulfide group, a thioketone group, or a heteroaromatic ring.)

[0207] The β-diketones in the above general formula are substituted or unsubstituted acetylacetone, and are specifically exemplified as follows.

[0208]

Chem.

[0209]

Chem.

[0210]

Chem.

[0211]

Chem.

[0212]

Chem.

[0213]

Chem.

[0214] R 1 and R 2 are generally the same β-diketones, but they may be different as described in JP-A-2004-175755. R 1 and R 2 Acetylacetone in which both are methyl groups is the most common, but it has the drawback of poor solubility in organic solvents. R 1 and R 2 The total number of carbon atoms of is preferably 3 or more, more preferably 4 or more.

[0215] It is preferable that the hydrogen atom of acetylacetone is substituted, and the larger the number of carbon atoms in the substituent, the easier it is to dissolve in an organic solvent. The larger the number of carbon atoms in the substituent, the more improved the film thickness uniformity when the metal-containing film-forming composition is spin-coated. Also, if the number of carbon atoms in the carboxylic acid is not too large, the shrinkage amount when forming a resist film will be small, and the amount of outgas components will also be small.

[0216] Acetylacetone forms a complex with a metal by enolization as shown below.

[0217] [Chemical formula]

[0218] The (B) metal source used in the metal-containing film-forming composition of the present invention is preferably a salt of a metal selected from Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi and a monovalent to tetravalent carboxylic acid having 1 to 30 carbon atoms. Specifically, it is more preferably a structure represented by the following formula (B-1).

[0219] [Chemical formula] (In the formula, M is selected from any of Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi, R1 is a monovalent organic group having 1 to 30 carbon atoms, and n is an integer of 1 to 4.)

[0220] From the viewpoints of solubility in an organic solvent, the amount of outgas components during baking, and productivity, R1 in the above formula (B-1) is more preferably a saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms, and even more preferably a branched alkyl group having 3 to 10 carbon atoms.

[0221] From the perspective of improving the exposure sensitivity of the resist upper layer film in EUV lithography, in the above formula (B-1), M is more preferably Ti, Hf, Sn, or Bi, and even more preferably Sn.

[0222] The content of the (B) metal source in the composition for forming a metal-containing film is preferably 1 to 1,000 parts by mass, and more preferably 5 to 900 parts by mass with respect to 100 parts by mass of the (A) silicon-containing polymer. When the content of the (B) metal source is 1 part by mass or more, the contribution to improving the exposure sensitivity of the resist upper layer film in EUV lithography becomes sufficient. When the content of the (B) metal source is 1,000 parts by mass or less, the adhesion to the resist upper layer film pattern becomes sufficient, and the collapse of the resist upper layer film pattern can be suppressed. These can be appropriately adjusted according to the required characteristics when used in the composition for forming a metal-containing film.

[0223] <(C) Organic solvent> As the (C) organic solvent that can be used in the composition for forming a metal-containing film of the present invention, there is no particular limitation as long as it can dissolve or disperse the above-mentioned (A) silicon-containing polymer, (B) metal source, and, if included, the (D) crosslinking agent, (E) acid generator, (F) surfactant, and (G) dye, and other additives described later.

[0224] Specifically, they are monoalkyl ethers such as ethylene glycol, diethylene glycol, and triethylene glycol, and monoalkyl ethers such as propylene glycol and dipropylene glycol. Specifically, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol monopropyl ether, ethylene glycol monopropyl ether, diacetone alcohol, 2-heptanone, cyclopentanone, cyclohexanone, and γ-butyrolactone, or a mixture containing one or more of these is preferably used.

[0225] The blending amount of the organic solvent is preferably 200 to 10,000 parts, more preferably 250 to 5,000 parts, per 100 parts by mass of the (B) metal source.

[0226] <(C’) High-boiling solvent> In the composition for forming a metal-containing film of the present invention, the (C) organic solvent may contain a (C’) high-boiling solvent.

[0227] (C’) The high-boiling solvent can be one or more organic solvents having a boiling point of 180 degrees (°C) or higher.

[0228] For example, as the (C) organic solvent, a mixture of one or more organic solvents having a boiling point of less than 180°C and one or more organic solvents having a boiling point of 180°C or higher ((C’) high-boiling solvent) may be used.)

[0229] (C’) As the high-boiling solvent, there are no particular restrictions as long as it can dissolve or disperse each component of the composition for forming a metal-containing film of the present invention, and examples include hydrocarbons, alcohols, ketones, esters, ethers, chlorinated solvents, etc. Specific examples include 1-octanol, 2-ethylhexanol, 1-nonanol, 1-decanol, 1-undecanol, ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,5-hexanediol, 2,4-heptanediol, 2-ethyl-1,3-Hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, glycerin, n-nonyl acetate, monohexyl ether, ethylene glycol mono-2-ethylhexyl ether, ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, diethylene glycol monoethyl ether, diethylene glycol monoisopropyl ether, diethylene glycol mono-n-butyl ether, diethylene glycol monoisobutyl ether, diethylene glycol monohexyl ether, diethylene glycol monophenyl ether, diethylene glycol monobenzyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol monomethyl ether, triethylene glycol-n-butyl ether, triethylene glycol butyl methyl ether, tetraethylene glycol dimethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-n-butyl ether, tripropylene glycol dimethyl ether, tripropylene glycol monomethyl ether, tripropylene glycol mono-n-propyl ether, tripropylene glycol mono-n-butyl ether, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, triacetin, propylene glycol diacetate, dipropylene glycol methyl-n-propyl ether, dipropylene glycol methyl ether acetate, 1,4-butanediol diacetate, 1,3-butylene glycol diacetate, 1,Examples thereof include 6 - hexanediol diacetate, triethylene glycol diacetate, γ - butyrolactone, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, dihexyl malonate, diethyl succinate, dipropyl succinate, dibutyl succinate, dihexyl succinate, dimethyl adipate, diethyl adipate, dibutyl adipate, triethanolamine, etc., and these may be used alone or in combination.,

[0230] (C’) The high - boiling solvent may be appropriately selected from, for example, the above - mentioned ones according to the temperature for heat - treating the resist underlayer film - forming composition of the present invention. The boiling point of the high - boiling solvent is preferably 180°C to 300°C, and more preferably 200°C to 300°C. With such a boiling point, there is no fear that the volatilization during baking (heat - treatment) will be too fast, so it is possible to suppress the occurrence of defects caused by drying during film formation. Also, with such a boiling point, it will not remain in the film without volatilizing even after baking, so there is no fear of adversely affecting the film physical properties such as etching resistance.,

[0231] In addition, when using the (C’) high - boiling solvent, the blending amount is preferably 1 to 30 parts by mass with respect to 100 parts by mass of the organic solvent having a boiling point of less than 180°C. With such a blending amount, sufficient thermal fluidity can be imparted during baking, and it will not remain in the film and lead to deterioration of film physical properties such as etching resistance, so it is preferable.,

[0232] <Other components> The above - mentioned metal - containing film - forming composition may contain at least one or more of (D) cross - linking agent, (E) acid generator, (F) surfactant, and (G) pigment as required.,

[0233] Hereinafter, components other than the above - mentioned (A) resin, (B) metal source, and (C) organic solvent that can be contained in the metal - containing film - forming composition of the present invention will be described.,

[0234] <(D) Cross - linking agent> In addition, in order to enhance the curability and further suppress the intermixing with the resist upper layer film, a (D) crosslinking agent can be added to the composition for forming a metal-containing film of the present invention.

[0235] The crosslinking agent is not particularly limited, and various known types of crosslinking agents can be widely used. As an example, a melamine-based crosslinking agent, a glycoluril-based crosslinking agent, a benzoguanamine-based crosslinking agent, a urea-based crosslinking agent, a β-hydroxyalkylamide-based crosslinking agent, an isocyanurate-based crosslinking agent, an aziridine-based crosslinking agent, an oxazoline-based crosslinking agent, and an epoxy-based crosslinking agent can be exemplified.

[0236] The above (D) crosslinking agent can be used alone or in combination of two or more. When adding the crosslinking agent, the addition amount is preferably 5 to 100 parts, more preferably 10 to 50 parts, based on 100 parts of the above (A) silicon-containing polymer. If the addition amount is 5 parts or more, sufficient curability can be exhibited and the intermixing with the resist upper layer film can be suppressed. On the other hand, if the addition amount is 50 parts or less, there is no risk of deterioration of dry etching resistance due to a low ratio of the (B) metal source in the composition.

[0237] Specific examples of the melamine-based crosslinking agent include hexamethoxymethylated melamine, hexabutoxymethylated melamine, their alkoxy and / or hydroxy-substituted products, and their partial self-condensates.

[0238] Specific examples of the glycoluril-based crosslinking agent include tetramethoxymethylated glycoluril, tetrabutoxymethylated glycoluril, their alkoxy and / or hydroxy-substituted products, and their partial self-condensates.

[0239] Specific examples of the benzoguanamine-based crosslinking agent include tetramethoxymethylated benzoguanamine, tetrabutoxymethylated benzoguanamine, their alkoxy and / or hydroxy-substituted products, and their partial self-condensates.

[0240] As the urea-based crosslinking agent, specifically, dimethoxymethylated dimethoxyethyleneurea, its alkoxy and / or hydroxy substitution products, and their partial self-condensates can be exemplified.

[0241] As the β-hydroxyalkylamide-based crosslinking agent, specifically, N,N,N’,N’-tetrakis(2-hydroxyethyl) adipic acid amide can be exemplified.

[0242] As the isocyanurate-based crosslinking agent, specifically, triglycidyl isocyanurate and triallyl isocyanurate can be exemplified.

[0243] As the aziridine-based crosslinking agent, specifically, 4,4’-bis(ethyleneiminocarbonylamino) diphenylmethane and 2,2-bishydroxymethylbutanol-tris[3-(1-aziridinyl) propionate] can be exemplified.

[0244] As the oxazoline-based crosslinking agent, specifically, 2,2’-isopropylidene bis(4-benzyl-2-oxazoline), 2,2’-isopropylidene bis(4-phenyl-2-oxazoline), 2,2’-isopropylidene bis(4-phenyl-2-oxazoline), 2,2’-methylene bis 4,5-diphenyl-2-oxazoline, 2,2’-methylene bis-4-phenyl-2-oxazoline, 2,2’-methylene bis-4-tert butyl-2-oxazoline, 2,2’-bis(2-oxazoline), 1,3-phenylene bis(2-oxazoline), 1,4-phenylene bis(2-oxazoline), and 2-isopropenyl oxazoline copolymer can be exemplified.

[0245] As the epoxy-based crosslinking agent, specifically, diglycidyl ether, ethylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,4-cyclohexanedimethanol diglycidyl ether, poly(glycidyl methacrylate), trimethylolethane triglycidyl ether, trimethylolpropane triglycidyl ether, and pentaerythritol tetraglycidyl ether can be exemplified.

[0246] Examples of the epoxy crosslinking agent and the oxetane crosslinking agent include, but are not limited to, those shown below.

[0247]

Chemical formula

[0248] The above compounds are commercially available, and the epoxy crosslinking agent and the oxetane crosslinking agent can also be obtained by reacting a hydroxyl group with epibromohydrin, 3-bromomethyloxetane, etc. as shown in the following formula. In the following formula, R5 is a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms that is saturated or 2 to 20 carbon atoms that is unsaturated, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted arylalkyl group having 7 to 31 carbon atoms. Also, not all of the hydroxyl groups can be reacted and some can be left. At this time, it is preferable that the number of epoxy + oxetane > the number of hydroxyl groups, and more preferably the number of epoxy + oxetane > the number of hydroxyl groups * 2.

[0249] The content of these compounds is preferably 5 to 100 parts by mass, more preferably 10 to 50 parts by mass, based on 100 parts by mass of the (B) metal source.

[0250]

Chemical formula

[0251] Specific examples of the compound having a hydroxyl group that can be used in the above reaction include, but are not limited to, the following.

[0252]

Chemical formula

[0253] <(E) Acid generator> One or more acid generators may be further added to the composition for forming a metal-containing film of the present invention. As the acid generator, any substance that acts as an acid precursor, such as a thermal acid generator, a photoacid generator, or an acid proliferator, may be used. However, in the present invention, it is more preferable that the acid generator to be added is a sulfonium salt and is a photoacid generator that generates an acid by the action of high-energy rays. Specifically, the materials described in paragraphs

[0061] to

[0085] of JP-A-2007-199653 can be added, but are not limited thereto.

[0254] The above acid generators can be used alone or in combination of two or more. When adding an acid generator, the addition amount is preferably 0.05 to 50 parts by mass, more preferably 0.1 to 10 parts by mass, based on 100 parts by mass of the silicon-containing polymer (A).

[0255] <(F) Surfactant> Furthermore, in the present invention, a surfactant can be added to the composition as needed. Specifically, the materials described in paragraph

[0185] of JP-A-2009-126940 can be added.

[0256] The preferable addition amount is preferably 0.01 to 5 parts by mass, more preferably 0.1 to 1 part by mass, based on 100 parts by mass of the silicon-containing polymer (A).

[0257] <(G) Dye> Furthermore, in the present invention, a dye can be added to the composition as needed. Specifically, the materials described in paragraph

[0135] of JP-A-2023-180781 can be added.

[0258] 〔Other Components〕 (Crosslinking Catalyst) In the present invention, a crosslinking catalyst (Xc) may be added to the composition for forming a metal-containing film. Examples of the crosslinking catalyst that can be added include compounds represented by the following general formula (Xc0). L a Hb A (Xc0) (In the formula, L is lithium, sodium, potassium, rubidium, cesium, sulfonium, iodonium, phosphonium or ammonium. A is a non-nucleophilic counter ion. a is an integer of 1 or more, b is 0 or an integer of 1 or more, and a + b is the valence of the non-nucleophilic counter ion.)

[0259] Specific crosslinking catalysts used in the present invention as (Xc0) include sulfonium salts of the following general formula (Xc-1), iodonium salts of the following general formula (Xc-2), phosphonium salts of the following general formula (Xc-3), ammonium salts of the following general formula (Xc-4), alkali metal salts, etc., and polysiloxanes (Xc-10) having a sulfonium salt, phosphonium salt, iodonium salt as part of the structure. Specifically, materials described in paragraphs

[0124] to

[0163] of JP-A-2020-118960 can be added, etc.

[0260]

Chemical formula

Chemical formula

[0261] The above crosslinking catalysts (Xc-1), (Xc-2), (Xc-3), (Xc-4), (Xc-10) can be used alone or in combination of two or more. The addition amount of the crosslinking catalyst is preferably 0.01 to 50 parts by mass, more preferably 0.1 to 40 parts by mass, based on 100 parts by mass of the base polymer (for example, the thermally crosslinkable polysiloxane (Sx) obtained by the above method).

[0262] The composition for forming a metal-containing film of the present invention may further contain the following raw materials.

[0263] (Organic acid) In order to improve the stability of the silicon-containing polymer (A) in the present invention, it is preferable to add a monovalent or divalent or higher organic acid having 1 to 30 carbon atoms.

[0264] Examples of the acid added at this time include formic acid, acetic acid, propionic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, oleic acid, stearic acid, linoleic acid, linolenic acid, benzoic acid, phthalic acid, isophthalic acid, terephthalic acid, salicylic acid, trifluoroacetic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, oxalic acid, malonic acid, methylmalonic acid, ethylmalonic acid, propylmalonic acid, butylmalonic acid, dimethylmalonic acid, diethylmalonic acid, succinic acid, methyl succinic acid, glutaric acid, adipic acid, itaconic acid, maleic acid, fumaric acid, citraconic acid, citric acid, etc. Particularly, oxalic acid, maleic acid, formic acid, acetic acid, propionic acid, citric acid, etc. are preferable. Further, in order to maintain stability, two or more kinds of acids may be mixed and used.

[0265] The addition amount of the organic acid is 0.001 to 25 parts by mass, preferably 0.01 to 15 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the (A) silicon-containing polymer contained in the composition for forming a metal-containing film of the present invention.

[0266] Alternatively, when the above organic acid is converted to the pH of the composition for forming a metal-containing film of the present invention, it is preferably formulated so that 0 ≦ pH ≦ 7, more preferably 0.3 ≦ pH ≦ 6.5, and still more preferably 0.5 ≦ pH ≦ 6.

[0267] (Water) In the present invention, water may be added to the composition. When water is added, in the case where polysiloxane (Sx) is used for the (A) silicon-containing polymer in the composition for forming a metal-containing film of the present invention, the polysiloxane (Sx) compound is hydrated, so that the lithography performance is improved. The water content in the solvent component of the composition for forming a metal-containing film of the present invention exceeds 0% by mass and is less than 50% by mass, particularly preferably 0.3 to 30% by mass, and still more preferably 0.5 to 20% by mass. If the addition amount of water is within the above range, the film thickness uniformity of the metal-containing film is good, there is no fear of repulsion occurring, and there is no fear of deterioration of the lithography performance.

[0268] The amount of the total solvent containing water is preferably 100 to 100,000 parts by mass, particularly 200 to 50,000 parts by mass, based on 100 parts by mass of the silicon-containing polymer (Sx) which is the base polymer.

[0269] (Stabilizer) Furthermore, in the present invention, a stabilizer can be added to the composition. As the stabilizer, a monohydric or polyhydric alcohol having a cyclic ether as a substituent can be added. In particular, adding the stabilizer described in paragraphs

[0181] to

[0182] of Japanese Patent Application Laid-Open No. 2009-126940 can improve the stability of the composition for forming a metal-containing film.

[0270] (Method for forming a metal-containing film) In the present invention, there is provided a method for forming a filling film that functions as a resist underlayer film or an intermediate film of a multilayer resist film used in lithography, using the above-described composition for forming a metal-containing film.

[0271] In the method for forming a metal-containing film using the composition for forming a metal-containing film of the present invention, the above-described composition for forming a metal-containing film is coated on a substrate to be processed by a spin coating method or the like. By using a spin coating method or the like, good planarization characteristics can be obtained. After spin coating, the solvent is evaporated, and baking (heat treatment) is performed to promote a crosslinking reaction in order to prevent mixing with the resist upper layer film. The baking is preferably performed in the range of 100°C or higher and 600°C or lower for 10 to 600 seconds, more preferably in the range of 200°C or higher and 500°C or lower for 10 to 300 seconds. Considering the influence on device damage and wafer deformation, the upper limit of the heating temperature in the wafer process of lithography is preferably 600°C or lower, more preferably 500°C or lower.

[0272] Also, in the method for forming a metal-containing film using the composition for forming a metal-containing film of the present invention, the composition for forming a metal-containing film of the present invention is coated on a substrate to be processed by the spin coating method or the like as described above, and the composition for forming a metal-containing film is fired and cured in an atmosphere having an oxygen concentration of 0.1% by volume or more and 21% by volume or less to form a metal-containing film.

[0273] By firing the composition for forming a metal-containing film of the present invention in such an oxygen atmosphere, a sufficiently cured film can be obtained. As the atmosphere during baking, air may be used, but it is preferable to enclose an inert gas such as N2, Ar, or He to reduce oxygen in order to prevent oxidation of the metal-containing film. In order to prevent oxidation, it is necessary to control the oxygen concentration, preferably 1000 ppm or less, more preferably 100 ppm or less (volume basis). Preventing oxidation of the metal-containing film during baking is preferable because absorption does not increase and etching resistance does not decrease.

[0274] <Pattern formation method> Further, in the present invention, as a pattern formation method by a two-layer resist process using the above-described composition for forming a metal-containing film, (I-1) A step of forming a metal-containing film by applying the composition for forming a metal-containing film of the present invention on a substrate to be processed and then performing heat treatment, (I-2) A step of forming a resist upper layer film on the metal-containing film using a photoresist material, (I-3) A step of pattern-exposing the resist upper layer film and then developing it with a developer to form a pattern in the resist upper layer film, (I-4) A step of transferring a pattern to the metal-containing film by dry etching using the resist upper layer film having the pattern as a mask, and (I-5) A step of processing the substrate to be processed using the metal-containing film having the pattern as a mask to form a pattern on the substrate to be processed A pattern formation method having the above steps is provided.

[0275] Since the resist upper layer film of the two-layer resist process exhibits etching resistance to fluorine-based gases and chlorine-based gases, in the two-layer resist process, it is preferable to perform dry etching of the metal-containing film using the resist upper layer film as a mask using an etching gas mainly composed of a fluorine-based gas or a chlorine-based gas.

[0276] In the present invention, as a pattern formation method by a three-layer resist process using the above-described composition for forming a metal-containing film, (II-1) A step of forming an organic resist lower layer film on a substrate to be processed, (II-2) A step of forming a metal-containing film by applying the composition for forming a metal-containing film of the present invention on the organic resist lower layer film and then performing heat treatment, (II-3) A step of forming a resist upper layer film using a photoresist material on the metal-containing film, (II-4) A step of forming a pattern in the resist upper layer film by pattern exposure of the resist upper layer film and then developing with a developer, (II-5) A step of transferring the pattern to the metal-containing film by dry etching using the resist upper layer film having the pattern as a mask, (II-6) A step of transferring the pattern to the organic resist lower layer film by dry etching using the metal-containing film having the pattern transferred thereto as a mask, and (II-7) A step of processing the substrate to be processed using the organic resist lower layer film having the pattern formed thereon as a mask to form a pattern on the substrate to be processed A pattern formation method having the above steps is provided.

[0277] Since the resist intermediate film (metal-containing film) in the above three-layer resist process exhibits etching resistance to an oxygen-based gas, in the above three-layer resist process, it is preferable to perform dry etching of the organic resist lower layer film using an etching gas mainly composed of an oxygen-based gas with the resist intermediate film as a mask.

[0278] Since the organic resist lower layer film in the above three-layer resist process exhibits etching resistance to a fluorine-based gas, in the above three-layer resist process, it is preferable to perform dry etching of the substrate to be processed using an etching gas mainly composed of a fluorine-based gas with the organic resist lower layer film as a mask.

[0279] A method for forming a pattern by a three-layer resist process of the present invention will be described with reference to FIG. 1. First, after forming an organic resist lower layer film 2 on a substrate 1 to be processed (I-A), a metal-containing film 3 is formed as a resist intermediate film (I-B) using the composition for forming a metal-containing film of the present invention, and a resist upper layer film 4 is formed thereon using a photoresist material (I-C). Next, exposure P is performed on the resist upper layer film 4 using a mask 5 (I-D), and PEB (post-exposure bake) is performed (I-E). Next, development is performed to form a resist upper layer film pattern 4a (I-F). Next, using the resist upper layer film pattern 4a as a mask, the metal-containing film 3 is dry-etched to form a metal-containing film pattern 3a (I-G). Next, after removing the resist upper layer film pattern 4a, using the metal-containing film pattern 3a as a mask, the organic resist lower layer film 2 is dry-etched to form an organic resist lower layer film pattern 2a (I-H). Further, after removing the metal-containing film pattern 3a, using the organic resist lower layer film pattern 2a as a mask, the substrate 1 to be processed is etched to form a pattern 1a (I-I).

[0280] In the above pattern forming method, the resist upper layer film may be either positive or negative, and the same photoresist composition as the commonly used one can be used. Further, the photoresist composition may contain metal atoms such as Sn, In, Ga, Ge, Al, Ce, La, Cs, Zr, Hf, Ti, Bi, Sb, Zn. When forming the resist upper layer film with the above photoresist composition, it may be formed by a spin coating method or a vapor deposition treatment by CVD or ALD.

[0281] When forming the photoresist composition by the spin coating method, pre-baking is performed after resist coating, but the range of 60 to 180 ° C for 10 to 300 seconds is preferable. Thereafter, exposure is performed according to a conventional method, post-exposure bake (PEB), and development are performed to obtain a resist pattern. The thickness of the resist upper layer film is not particularly limited, but 10 to 500 nm, particularly 20 to 400 nm is preferable.

[0282] As the exposure light, high-energy rays with a wavelength of 300 nm or less can be mentioned, specifically, excimer lasers of 248 nm, 193 nm, and 157 nm, soft X-rays of 3 to 20 nm, electron beams, X-rays, etc.

[0283] As the method for forming the pattern on the resist upper layer film, pattern formation can be performed by photolithography with a wavelength of 5 nm or more and 300 nm or less, direct drawing by an electron beam, nanoimprinting, or a combination thereof. In the present invention, EUV light is most preferable. That is, in the step (I-3), it is preferable to perform the pattern exposure using EUV light, or in the step (II-4), it is preferable to perform the pattern exposure using EUV light.

[0284] Further, it is preferable that the developing method in the pattern forming method is development with an alkali or development with an organic solvent.

[0285] Next, etching is performed using the obtained resist pattern as a mask. The etching of the silicon-containing resist intermediate film (metal-containing film) in the three-layer resist process is performed using a fluorocarbon-based gas with the upper layer resist pattern as a mask. Thereby, a silicon-containing resist intermediate film (metal-containing film) pattern is formed.

[0286] Next, using the obtained silicon-containing resist intermediate film (metal-containing film) pattern as a mask, etching of the organic resist lower layer film is performed. The etching of the organic resist lower layer film is preferably performed using an etching gas mainly composed of an oxygen-based gas.

[0287] The etching of the next workpiece can also be performed by a conventional method. For example, if the workpiece is SiO2, SiN, or a silica-based low dielectric constant insulating film, etching mainly using a fluorocarbon-based gas is performed. When the substrate processing is etched with a fluorocarbon-based gas, the silicon-containing resist intermediate film (metal-containing film) pattern in the three-layer resist process is peeled off simultaneously with the substrate processing.

[0288] The silicon-containing film (metal-containing film) obtained by the composition for forming a metal-containing film of the present invention is characterized by excellent etching resistance during etching of these workpieces.

[0289] The workpiece (workpiece substrate) is not particularly limited, and substrates such as Si, α-Si, p-Si, SiO2, SiN, SiON, W, TiN, Al, etc., or those with a processed layer formed on the substrate are used. As the processed layer, various Low-k films such as Si, SiO2, SiON, SiN, p-Si, α-Si, W, W-Si, Al, Cu, Al-Si, etc., and their stopper films are used, and it can usually be formed with a thickness of 50 to 10,000 nm, particularly 100 to 5,000 nm. When forming the processed layer, substrates and processed layers of different materials are used.

[0290] As the organic resist underlayer film material that can be used for the above organic resist underlayer film, those known as the underlayer film for the three-layer resist method or the two-layer resist method using a silicon resist composition, in addition to the 4,4'-(9-fluorenylidene) bisphenol novolak resin (molecular weight 11,000) described in JP-A-2005-128509, a number of resins including novolak resins, which are known as resist underlayer film materials for the two-layer resist method and the three-layer resist method, etc. can be used. Also, when it is desired to increase the heat resistance compared to ordinary novolak, a polycyclic skeleton such as 6,6'-(9-fluorenylidene)-di(2-naphthol) novolak resin can be incorporated, and a polyimide-based resin can also be selected (for example, JP-A-2004-153125).

[0291] The above organic resist underlayer film can be formed on the workpiece substrate by a spin coating method or the like using a composition solution, similar to a photoresist composition. After forming the organic resist underlayer film by a spin coating method or the like, it is desirable to bake to evaporate the organic solvent. The baking temperature is preferably in the range of 80 to 400 °C, and the baking time is preferably in the range of 10 to 300 seconds.

[0292] Instead of the above-mentioned organic resist lower layer film material, it is also possible to apply an organic hard mask formed by CVD method or ALD method.

Examples

[0293] Hereinafter, the present invention will be specifically described by showing synthesis examples, examples and comparative examples, but the present invention is not limited by these descriptions. In the following examples, % represents mass %, and the molecular weight Mw is the weight average molecular weight in terms of polystyrene by GPC measurement.

[0294] <Preparation of polysiloxane compound> [Synthesis Example 1] To a mixture of 120 g of methanol, 0.1 g of 10% nitric acid and 60 g of deionized water, a mixture of 30.6 g of compound (101), 38.1 g of compound (102) and 5.9 g of compound (110) was added, and the mixture was kept at 40 °C for 12 hours for hydrolysis and condensation. After completion of the reaction, 600 g of propylene glycol ethyl ether (PGEE) was added, and the water and by-produced alcohol used for hydrolysis and condensation were distilled off under reduced pressure to obtain 440 g of a PGEE solution of polysiloxane compound 1 (compound concentration 10%). When the polystyrene-reduced molecular weight of polysiloxane compound 1 was measured, Mw = 2,900.

[0295] [Synthesis Examples 2 to 8] Under the same conditions as in Synthesis Example 1, [Synthesis Example 2] to [Synthesis Example 8] were carried out using the monomers shown in Table 1, and the target products were obtained respectively.

[0296]

Table 1

[0297] The compounds used in the examples and comparative examples are shown below. PhSi(OCH3)3 ··· Compound (100) CH3Si(OCH3)3 ··· Compound (101) Si(OCH3)4 ··· Compound (102)

[0298] [Chemical formula]

[0299] [Synthesis Example 9] 1400 g of ethanol, 700 g of ultrapure water, and 50 g of 25% tetramethylammonium hydroxide were added and made into a homogeneous solution at 40°C under a nitrogen atmosphere. After slowly dropping a mixture of 138.6 g of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and 37.2 g of phenyltrimethoxysilane, the reaction was carried out at 40°C for 2 hours. After completion of the reaction, 35 g of acetic acid was added to stop the reaction, and ethanol was distilled off under reduced pressure. 2000 ml of ethyl acetate was added to the solution after distillation, the aqueous layer was separated, the organic layer was washed twice with 400 ml of ultrapure water, 1000 g of PGMEA (propylene glycol monomethyl ether acetate) was added, and water and low-boiling solvents were distilled off to recover 600 g of a PGMEA solution of polysiloxane compound 9 (compound concentration 20%). When the polystyrene-reduced molecular weight of polysiloxane compound 9 was measured, Mw = 2800.

[0300] [Preparation of polycarbosilane] [Synthesis Example 10] In a nitrogen-filled reaction vessel, 2.9 g of magnesium and 5.5 g of tetrahydrofuran were added and stirred at 20°C. Next, 8.7 g of the compound represented by the following formula (Z-1), 2.2 g of the compound represented by the following formula (Z-2), and 4.7 g of the compound represented by the following formula (Z-3) were dissolved in 56 g of tetrahydrofuran to prepare a monomer solution. The inside of the reaction vessel was set to 20°C, and the above monomer solution was added dropwise over 1 hour while stirring. The end of the dropwise addition was taken as the start time of the reaction, and the reaction was carried out at 40°C for 1 hour and then at 60°C for 3 hours. After completion of the reaction, 33 g of tetrahydrofuran was added, and the polymerization solution was ice-cooled and cooled to 10°C or lower. After adding 15.2 g of triethylamine to the cooled polymerization solution, 4.8 g of methanol was added dropwise from a dropping funnel over 10 minutes while stirring. The end of the dropwise addition was taken as the start time of the reaction, and the reaction was carried out at 20°C for 1 hour. The polymerization solution was poured into 110 g of diisopropyl ether, and the precipitated salt was filtered off. Next, using an evaporator, tetrahydrofuran, excess triethylamine, and excess methanol in the filtrate were removed. The obtained residue was poured into 28 g of diisopropyl ether, the precipitated salt was filtered off, and 20 g of cyclohexanone was added to the filtrate. By removing diisopropyl ether in the solution using an evaporator, a cyclohexanone solution of polycarbosilane compound 10 with a solid content concentration of 8% by mass was obtained. The Mw of polycarbosilane compound 10 was 1,960.

[0301] [Chemical formula]

[0302] [Preparation of polysilane compound] [Synthesis Example 11] 10.0 g of Ogsol SI-10-20 (Mw 1,900) manufactured by Osaka Gas Chemical Co., Ltd. was dissolved in 100.0 g of tetrahydrofuran, and 6.0 g of triethylamine and 16.0 g of ultrapure water were added. After reacting this solution under reflux for 7 hours, 375 g of propylene glycol monoethyl ether (PGEE) was added and concentrated under reduced pressure to obtain 91.3 g of a PGEE solution of polysilane compound 11 (polymer concentration 11%). Mw was 980.

[0303] [Synthesis Example 12] 10.0 g of OGSOL SI-20-10 (Mw 1,300) manufactured by Osaka Gas Chemical Co., Ltd. was dissolved in 100.0 g of tetrahydrofuran, and 2.0 g of 29% aqueous ammonia and 6.0 g of ultrapure water were added. After reacting this solution under reflux for 6.5 hours, 250 g of propylene glycol monoethyl ether (PGEE) was added and concentrated under reduced pressure to obtain 70.3 g of a PGEE solution of polysilane compound 12 (polymer concentration 15%). Mw was 870.

[0304] [Synthesis Example 13] 10.0 g of OGSOL SI-20-10 modified (Mw 1,400) manufactured by Osaka Gas Chemical Co., Ltd. was dissolved in 100.0 g of tetrahydrofuran, and 6.0 g of triethylamine and 16.0 g of ultrapure water were added. After reacting this solution under reflux for 12 hours, 250 g of propylene glycol monoethyl ether (PGEE) was added and concentrated under reduced pressure to obtain 71.3 g of a PGEE solution of polysilane compound 133 (polymer concentration 14%). Mw was 830.

[0305] Table 2 summarizing the blending amounts of Synthesis Examples 11 to 13 is shown below.

[0306]

Table 2

[0307] [Synthesis Example 14] A mixture of 17.0 g of methyltrimethoxysilane (101), 5.0 g of phenyltrimethoxysilane (100), 45.7 g of tetramethoxysilane (102), and 54.6 g of a PGEE solution of polysilane compound 11 was added to a mixture of 120 g of PGEE, 1 g of 70% nitric acid, and 60 g of deionized water, and the mixture was maintained at 40 °C for 12 hours for hydrolysis and condensation. After completion of the reaction, 300 g of PGEE was added, and the by-produced alcohol and excess water were distilled off under reduced pressure to obtain 300 g of a PGEE solution of polysilane compound 14 (polymer concentration 12%). Mw was 3,000.

[0308] [Synthesis Example 15] To a mixture of 80 g of PGEE, 1 g of 70% nitric acid, and 60 g of deionized water, a mixture of 17.0 g of methyltrimethoxysilane (101), 5.0 g of phenyltrimethoxysilane (100), 45.7 g of tetramethoxysilane (102), and 43.6 g of a PGEE solution of polysilane compound 13 was added, and the mixture was maintained at 40 °C for 12 hours for hydrolysis and condensation. After completion of the reaction, 300 g of PGEE was added, and the by-produced alcohol and excess water were distilled off under reduced pressure to obtain 320 g of a PGEE solution of polysilane compound 15 (polymer concentration 11%). Mw was 2,900.

[0309] Table 3 summarizing the compounding amounts of Synthesis Examples 14 to 15 is shown below.

[0310]

Table 3

[0311] [Examples, Comparative Examples] The polysiloxane compounds 1 to 9, polycarbosilane compound 10, polysilane compounds 11 to 15 obtained in the above synthesis examples, metal sources represented by the following general formulas (M-1 to 17), crosslinking agents (XL-1 to 2), crosslinking catalysts, acid generators (PAG-1 to 4), and solvents were mixed at the ratios shown in Tables 5-1 to 5-2, and filtered through a 0.1 μm fluororesin filter to prepare composition solutions for forming metal-containing films, designated as UDL-1 to 49 and Comparative Example UDL-1 to 3, respectively.

[0312] [Metal Salts (M-1) to (M-17)] The following metal compounds were used as the metal salts. (M-1): Titanium(IV) 2-ethylhexanoate (M-2): Tris(2,2,6,6-tetramethyl-3,5-heptanedionato)chromium(III) (M-3): Tris(2,2,6,6-tetramethyl-3,5-heptanedionato)manganese(III) (M-4): Tris(2,2,6,6-tetramethyl-3,5-heptanedionato)iron(III) (M-5): Cobalt(II) 2-ethylhexanoate (M-6): Nickel(II) bis(hexafluoroacetylacetonate) (M-7): Copper(I) 2-ethylhexanoate (M-8): Zinc(II) 4-vinylbenzoate (M-9): Zirconium(IV) tetra(2,2,6,6-tetramethyl-3,5-heptanedionato) (M-10): Molybdenum(IV) 2-ethylhexanoate (M-11): Indium(III) ethylbutyrate (M-12): Tin(II) acetate (M-13): Tin(II) 2-ethylhexanoate (M-14): Tin(II) acetylacetonate (M-15): Tin(II) 4-fluorobenzoate (M-16): Hafnium(IV) carboxyethyl acrylate (M-17): Bismuth(III) 2-ethylhexanoate

[0313] [Crosslinking agents XL-1 to XL-2)] The crosslinking agents (XL-1) to (XL-2) used in the metal-containing film-forming composition are shown below. [Chemical formula]

[0314] The crosslinking catalysts used are as follows. XLC-1 ··· Triphenylsulfonium nitrate XLC-2 ··· Monotriphenylsulfonium maleate XLC-3 ··· Triethylphenylammonium iodide

[0315] The solvents used are as follows. PGEE ··· Propylene glycol ethyl ether PGMEA ··· Propylene glycol methyl ether acetate

[0316] The photoacid generator used is as shown in Table 4 below.

[0317]

Table 4

[0318] For the high-boiling solvent (C-1), ethylene glycol dibenzyl ether with a boiling point of 364 °C was used.

[0319] For the metal source (R-1) in the comparative example, ZrO2 nanoparticles (average primary particle diameter 5 nm, 915505, Sigma-Aldrich Corp) were used.

[0320]

Table 5-1

[0321]

Table 5-2

[0322] [Examples 1-1 to 1-49, Comparative Examples 1-1 to 1-3: Etching Resistance] The metal-containing film-forming compositions (UDL-1 to 49 and Comparative Example UDL-1 to 3) were applied onto a silicon substrate, heated at 220 °C for 60 seconds using a hot plate to form a metal-containing film with a film thickness of 10 nm, and the film thickness A was measured. Subsequently, etching with O2 gas was performed for 20 seconds under the following conditions using a dry etching apparatus TE-8500 manufactured by Tokyo Electron Limited, and the film thickness B was measured. The film thickness etched in 20 seconds (film thickness B - film thickness A) was calculated as the etching resistance.

[0323] In the etching using O2 gas, when the film thickness difference between B and A was less than 5 nm, it was rated as "A" (extremely good), when it was 5 nm or more and less than 15 nm, it was rated as "B" (good), and when it was 15 nm or more, it was rated as "C" (poor). The results are shown in Tables 6-1 to 6-2.

[0324] The O2-based gas etching conditions are as shown below. Chamber pressure 500 mT RF power 100 W O2 gas flow rate 30 sccm N2 gas flow rate 270 sscm Time 20 sec

[0325]

Table 6-1

[0326]

Table 6-2

[0327] As shown in Tables 6-1 to 6-2, Examples 1-1 to 1-49 using the composition for forming a metal-containing film of the present invention were found to exhibit good etching resistance to O2 gas. On the other hand, in Comparative Example 1-1 using Comparative Example UDL-1 containing no (B) metal source, deterioration of dry etching resistance was confirmed. From the above, the composition for forming a metal-containing film containing the (B) metal source of the present invention can provide an excellent patterning method capable of transferring a resist upper layer film pattern onto a substrate to be processed with high precision.

[0328] [Examples 2-1 to 2-49, Comparative Examples 2-1 to 2-3: Patterning test (sensitivity evaluation)] On a silicon wafer on which 100 nm of SiO2 was formed, as an organic resist lower layer film, a SOC film (ODL-306 carbon content 61 atomic%) manufactured by Shin-Etsu Chemical Co., Ltd. was used, spin-coated, and baked at 350 °C for 60 seconds to produce a carbon film with a film thickness of 45 nm. Next, the above composition for forming a metal-containing film (UDL-1 to 49 and Comparative Examples UDL-1 to 3) was applied onto the organic resist lower layer film, and heated at 220 °C for 60 seconds using a hot plate to form a resist intermediate film with a film thickness of 10 nm.

[0329] Subsequently, the resist material with the composition shown in Table 7 was spin-coated on the above resist intermediate film and pre-baked at 105°C for 60 seconds using a hot plate to produce a resist film with a thickness of 35 nm. This was then exposed using an EUV scanner NXE3300 manufactured by ASML (NA 0.33, σ 0.9 / 0.6, quadrupole illumination, L / S pattern with a pitch of 44 nm in wafer dimensions), PEB was performed on a hot plate at 100°C for 60 seconds, and development was carried out for 30 seconds with a 2.38 mass% TMAH aqueous solution to obtain a pattern with a line dimension of 22 nm.

[0330] The line dimension was measured using a length measurement SEM (CG5000) manufactured by Hitachi High-Technologies Corporation, and pattern collapse was observed. For those formed without pattern collapse, the following evaluations were subsequently carried out.

[0331] The cross-sectional shape was observed using an electron microscope (S-4800) manufactured by Hitachi High-Technologies Corporation. Also, when the line dimension was made thinner by increasing the exposure dose, the minimum dimension at which the line resolved without collapse was determined and taken as the collapse limit (nm). The smaller the numerical value, the higher the collapse resistance and the more preferable.

[0332] Also, the exposure dose at which a line dimension of 22 nm was obtained was evaluated as the sensitivity, and it was determined that the smaller the exposure dose, the more it contributed to the high sensitivity of the resist upper layer film. The results are shown in Table 9.

[0333]

Chemical formula

[0334]

Chemical formula

[0335]

Table 7

[0336] Next, using the resist upper layer film pattern as a mask by dry etching, the resist intermediate film was etched to form a hard mask pattern. Using the obtained hard mask pattern as a mask, the organic lower layer film was etched to form a pattern. Using the obtained resist lower layer film pattern as a mask, the SiO2 film was etched. The etching conditions are as shown below.

[0337] The pattern cross-section was observed with an S-4800 (electron microscope manufactured by Hitachi, Ltd.). The results are shown in Tables 8-1 to 8-2. The processed line dimensions were measured using a length measurement SEM (CG5000) manufactured by Hitachi High-Technologies Corporation, and the critical dimension and LWR of pattern collapse were observed.

[0338] (1) Processing conditions for the resist intermediate film Equipment: Dry etching equipment Telius SP manufactured by Tokyo Electron Limited Etching conditions (1): Chamber pressure: 80 mT RF power (upper): 500 W RF power (lower): 300 W CF4 gas flow rate: 150 sccm CHF3 gas flow rate: 50 sccm Time: 10 sec

[0339] (2) Processing conditions for the organic resist lower layer film Chamber pressure: 80 mT RF power (upper): 500 W RF power (lower): 300 W CO2 gas flow rate: 320 sccm N2 gas flow rate: 80 sccm Time: 40 sec

[0340] (3) Processing conditions for the oxide film (substrate to be processed) Chamber pressure: 10 mT RF power (top): 100W RF power (bottom): 800W CF4 gas flow rate: 25sccm CHF3 gas flow rate: 15 sccm O2 gas flow rate: 5sccm Time: 60sec

[0341] [Table 8-1]

[0342] [Table 8-2]

[0343] As shown in Tables 8-1 and 8-2, in Examples 2-1 to 2-49, which used the metal-containing film-forming composition of the present invention, a vertical pattern cross section was obtained in the formation of a line width of 22 nm using EUV exposure, and it was observed that there was no pattern collapse. On the other hand, in Comparative Example 2-2, which used Comparative Example UDL-2, which did not contain a silicon-containing polymer, collapse of the resist pattern was observed.

[0344] Furthermore, it was found that Examples 2-1 to 2-7 and Example 2-35, which used a silicon-containing polymer containing a polysiloxane containing an organic group having one or more carbon-oxygen single bonds or carbon-oxygen double bonds, were able to form finer patterns than Example 2-8, which used a polysiloxane that did not contain an organic group having one or more carbon-oxygen single bonds or carbon-oxygen double bonds. It is presumed that these compositions, because they contain a silicon-containing polymer with excellent adhesion, showed excellent pattern collapse suppression effects and good pattern formation effects even for patterns with a line width of 22 nm.

[0345] When the composition for forming a metal-containing film of the present invention is used as a resist intermediate film, it is found that a pattern can be formed with high sensitivity (Examples 2-1 to 2-49). From this, it can be seen that the above resist intermediate film can contribute to improving the sensitivity while maintaining the LWR of the upper resist. In Examples 1-23 to 1-39 in which a silicon-containing polymer was fixed to Compound 9 and various (B) metal sources were added to evaluate the metal-containing film-forming compositions UDL-23 to 39, Examples 1-34 to 1-37 using a metal-containing film-forming composition containing Sn as the (B) metal source showed particularly excellent sensitivity.

[0346] In Comparative Example 2-1 using Comparative Example UDL-1 not containing the (B) metal source and Comparative Example 2-3 using Comparative Example UDL-3 containing metal nanoparticles as the (B) metal source, deterioration of the LWR after processing was observed. By X-ray diffraction method, it was revealed that the resist intermediate film formed using Comparative Example UDL-3 exhibited crystallinity. It is presumed that this deteriorated the line width roughness (LWR) of the pattern when the substrate to be processed was etched.

[0347] As described above, the present invention can break the trade-off relationship between sensitivity and LWR and form a resist underlayer film or intermediate film that can contribute to improving the sensitivity while maintaining the LWR of the upper resist, so it has high utility value in the field of EUV lithography.

[0348] This specification includes the following inventions.

[0349] [1]: A composition for forming a metal-containing film, comprising (A) a silicon-containing polymer containing polysiloxane, polycarbosilane, or polysilane, (B) a metal source, and (C) an organic solvent, wherein the (B) metal source is a salt of a metal selected from Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi and a monovalent to tetravalent carboxylic acid having 1 to 30 carbon atoms, or a complex of the metal and β-diketones.

[0350] [2]: The polysiloxane of the component (A) contains any one or more of the repeating units represented by the following general formula (Sx-1), the repeating units represented by the following general formula (Sx-2), and the partial structure represented by the following general formula (Sx-3), and is characterized in that it is the composition for forming a metal-containing film according to the above [1]. [Chemical formula] (In the formula, R a , R b , R c are each independently a monovalent organic group having 1 to 30 carbon atoms which may be the same or different. )

[0351] [3]: In the formulas (Sx-1) to (Sx-3), at least one of the R a to R c is an organic group having one or more carbon-oxygen single bonds or carbon-oxygen double bonds, and is characterized in that it is the composition for forming a metal-containing film according to the above [2].

[0352] [4]: The polycarbosilane of the component (A) contains a unit structure represented by the following general formula (Sy-1), and is characterized in that it is the composition for forming a metal-containing film according to any one of the above [1] to [3]. [Chemical formula] (In the formula, R d and R e are each independently a hydrogen atom, a hydroxy group, a halogen atom, or a monovalent organic group having 1 to 30 carbon atoms, and Z is a divalent hydrocarbon group having 1 to 20 carbon atoms which may be substituted or unsubstituted. )

[0353] [5]: The polysilane of the component (A) contains a repeating unit represented by the following general formula (Sz-1), and is characterized in that it is the composition for forming a metal-containing film according to any one of the above [1] to [4]. (R 9 R 10 R 11 Si) a2 (R 12 R 13 Si) a3 (R 14Si) a4 (Si) a5 (Sz-1) (wherein R 9 、R 10 、R 11 、R 12 、R 13 、and R 14 is each a methyl group, a phenyl group, or a hydroxyl group. a2, a3, a4, and a5 are mole fractions, and a2 + a3 + a4 + a5 = 1, 0 ≦ a2 ≦ 1, 0 ≦ a3 ≦ 1, 0 ≦ a4 ≦ 1, 0 ≦ a5 ≦ 1.)

[0354] [6]: The metal-containing film-forming composition according to any one of [1] to [5] above, wherein the (B) metal source is a salt of the metal and a monovalent to tetravalent carboxylic acid having 1 to 30 carbon atoms.

[0355] [7]: The metal-containing film-forming composition according to any one of [1] to [6] above, wherein the (B) metal source has a structure represented by the following formula (B-1). [Chemical formula] (wherein M is selected from any one of Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi, R1 is a monovalent organic group having 1 to 30 carbon atoms, and n is an integer of 1 to 4.)

[0356] [8]: The metal-containing film-forming composition according to [7] above, wherein R1 in the formula (B-1) is a saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms.

[0357] [9]: The metal-containing film-forming composition according to [7] or [8] above, wherein R1 in the formula (B-1) is a branched alkyl group having 3 to 10 carbon atoms.

[0358]

[10] : The metal-containing film-forming composition according to any one of [1] to [9] above, wherein the metal of the (B) metal source is Sn.

[0359]

[11] : The composition for forming a metal-containing film according to any one of [1] to

[10] above, characterized in that the composition further contains one or more of (D) a crosslinking agent, (E) an acid generator, (F) a surfactant, and (G) a pigment.

[0360]

[12] : The composition for forming a metal-containing film according to any one of [1] to

[11] above, characterized in that the (C) organic solvent is a mixture of one or more organic solvents having a boiling point of less than 180°C and one or more organic solvents ((C') high-boiling solvents) having a boiling point of 180°C or higher.

[0361]

[13] : A method for forming a pattern on a substrate to be processed, comprising: (I-1) a step of forming a metal-containing film by applying the composition for forming a metal-containing film according to any one of [1] to

[12] above on the substrate to be processed and then performing a heat treatment; (I-2) a step of forming a resist upper layer film on the metal-containing film using a photoresist material; (I-3) a step of exposing the resist upper layer film to a pattern and then developing it with a developer to form a pattern in the resist upper layer film; (I-4) a step of transferring the pattern to the metal-containing film by dry etching using the resist upper layer film having the pattern as a mask; and (I-5) a step of processing the substrate to be processed using the metal-containing film having the pattern as a mask to form a pattern on the substrate to be processed.

[0362]

[14] : A method for forming a pattern on a substrate to be processed, comprising: (II-1) forming an organic resist lower layer film on the substrate to be processed; (II-2) applying the composition for forming a metal-containing film according to any one of [1] to

[12] on the organic resist lower layer film, and then performing a heat treatment to form a metal-containing film; (II-3) forming a resist upper layer film on the metal-containing film using a photoresist material; (II-4) performing pattern exposure on the resist upper layer film, and then developing with a developer to form a pattern on the resist upper layer film; (II-5) using the resist upper layer film on which the pattern is formed as a mask, and transferring the pattern to the metal-containing film by dry etching; (II-6) using the metal-containing film on which the pattern is transferred as a mask, and transferring the pattern to the organic resist lower layer film by dry etching; and (II-7) using the organic resist lower layer film on which the pattern is formed as a mask to process the substrate to be processed and form a pattern on the substrate to be processed. The pattern formation method is characterized by comprising the above steps.

[0363]

[15] : The pattern formation method according to

[13] above, characterized in that in the step (I-3), the pattern exposure is performed using EUV light.

[0364]

[16] : The pattern formation method according to

[14] above, characterized in that in the step (II-4), the pattern exposure is performed using EUV light.

[0365] Note that the present invention is not limited to the above embodiments. The above embodiments are examples, and any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and exhibits the same operational effects is included in the technical scope of the present invention.

Explanation of Reference Numerals

[0366] 1... Substrate to be processed, 1a... Pattern, 2... Organic resist lower layer film, 2a... Pattern of organic resist lower layer film, 3... Metal-containing film, 3a... Pattern of metal-containing film, 4... Resist upper layer film, 4a…resist upper layer pattern, 5…mask, P…exposure.

Claims

1. A composition for forming a metal-containing film, comprising: (A) a silicon-containing polymer containing polysiloxane, polycarbosilane, or polysilane; (B) a metal source; and (C) an organic solvent, wherein the (B) metal source is a salt of a metal selected from Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi and a monovalent to tetravalent carboxylic acid having 1 to 30 carbon atoms, or a complex of the metal and β-diketones. The composition for forming a metal-containing film is characterized by this.

2. The polysiloxane of the component (A) contains any one or more of a repeating unit represented by the following general formula (Sx-1), a repeating unit represented by the following general formula (Sx-2), and a partial structure represented by the following general formula (Sx-3). The composition for forming a metal-containing film according to claim 1 is characterized by this. 【Chemical 1】 (In the formula, R ａ , R ｂ , R ｃ are each a monovalent organic group having 1 to 30 carbon atoms, which may be the same or different.

3. In the formulas (Sx-1) to (Sx-3), the R ａ to R ｃ The metal-containing film-forming composition according to claim 2, wherein at least one of them is an organic group having one or more carbon-oxygen single bonds or carbon-oxygen double bonds.

4. The polycarbosilane of the component (A) contains a unit structure represented by the following general formula (Sy-1). The composition for forming a metal-containing film according to claim 1 is characterized by this. 【Chemical Formula 2】 (wherein R ｄ and R ｅ are each independently a hydrogen atom, a hydroxy group, a halogen atom, or a monovalent organic group having 1 to 30 carbon atoms, and Z is a divalent hydrocarbon group having 1 to 20 carbon atoms which is substituted or unsubstituted.)

5. The polysilane of the component (A) contains a repeating unit represented by the following general formula (Sz-1). The composition for forming a metal-containing film according to claim 1 is characterized by this. (R ９ R １０ R １１ Si) ａ２ (R １２ R １３ Si) ａ３ (R １４ Si) ａ４ (Si) ａ５ (Sz-1) (wherein R ９ , R １０ , R １１ , R １２ , R １３ , and R １４ are each a methyl group, a phenyl group, or a hydroxyl group. a2, a3, a4, and a5 are mole fractions, and a2 + a3 + a4 + a5 = 1, 0 ≤ a2 ≤ 1, 0 ≤ a3 ≤ 1, 0 ≤ a4 ≤ 1, and 0 ≤ a5 ≤ 1.)

6. The (B) metal source is a salt of the metal and a monovalent to tetravalent carboxylic acid having 1 to 30 carbon atoms. The composition for forming a metal-containing film according to claim 1 is characterized by this.

7. The (B) metal source has a structure represented by the following formula (B-1). The composition for forming a metal-containing film according to claim 1 is characterized by this. 【Chemical Formula 3】 (In the formula, M is selected from any of Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi, and R １ is a monovalent organic group having 1 to 30 carbon atoms, and n is an integer of 1 to 4.)

8. R in the formula (B-1) １ The metal-containing film-forming composition according to claim 7, wherein R is a saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms.

9. R in the formula (B-1) １ The metal-containing film-forming composition according to claim 7, wherein is a branched alkyl group having 3 to 10 carbon atoms.

10. The metal of the (B) metal source is Sn. The composition for forming a metal-containing film according to claim 1 is characterized by this.

11. The composition further contains one or more of (D) a crosslinking agent, (E) an acid generator, (F) a surfactant, and (G) a pigment. The composition for forming a metal-containing film according to claim 1 is characterized by this.

12. The (C) organic solvent is a mixture of one or more organic solvents having a boiling point of less than 180°C and one or more organic solvents ((C') high-boiling solvents) having a boiling point of 180°C or higher. The composition for forming a metal-containing film according to claim 1 is characterized by this.

13. A method for forming a pattern on a substrate to be processed, Step (I-1): A step of forming a metal-containing film by applying the composition for forming a metal-containing film according to any one of claims 1 to 12 on a substrate to be processed and then performing heat treatment. Step (I-2): A step of forming an upper resist film using a photoresist material on the metal-containing film. Step (I-3): A step of forming a pattern in the upper resist film by performing pattern exposure on the upper resist film and then developing with a developer. Step (I-4): A step of transferring the pattern to the metal-containing film by dry etching using the upper resist film with the pattern formed thereon as a mask, and Step (I-5): A step of processing the substrate to be processed using the metal-containing film with the pattern formed thereon as a mask to form a pattern on the substrate to be processed A pattern formation method characterized by comprising the above steps.

14. A method for forming a pattern on a substrate to be processed, comprising: Step (II-1): A step of forming an organic resist lower layer film on a substrate to be processed. Step (II-2): A step of forming a metal-containing film by applying the composition for forming a metal-containing film according to any one of claims 1 to 12 on the organic resist lower layer film and then performing heat treatment. Step (II-3): A step of forming an upper resist film using a photoresist material on the metal-containing film. Step (II-4): A step of forming a pattern in the upper resist film by performing pattern exposure on the upper resist film and then developing with a developer. Step (II-5): A step of transferring the pattern to the metal-containing film by dry etching using the upper resist film with the pattern formed thereon as a mask. Step (II-6): A step of transferring the pattern to the organic resist lower layer film by dry etching using the metal-containing film with the pattern transferred thereon as a mask, and Step (II-7): A step of processing the substrate to be processed using the organic resist lower layer film with the pattern formed thereon as a mask to form a pattern on the substrate to be processed A pattern formation method characterized by comprising the above steps.

15. The pattern formation method according to claim 13, wherein in step (I-3), the pattern exposure is performed using EUV light.

16. The pattern formation method according to claim 14, wherein in step (II-4), the pattern exposure is performed using EUV light.

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