Metal-containing film forming composition and pattern forming method

Abstract

The invention relates to a metal-containing film forming composition and a pattern forming method. The present invention addresses the problem of providing: a metal-containing film-forming composition which has excellent dry etching resistance compared to conventional organic underlayer film materials and also has a high degree of landfill / planarization characteristics; and a pattern-forming method using the composition. [Solution] A metal-containing film-forming composition containing (A) a metal compound containing at least one metal selected from the group consisting of Ti, Zr, and Hf, (B) a cross-linking agent having two or more and four or less cyclic ether structures having 2-13 carbon atoms in the molecule, and (C) a solvent. The metal-containing film-forming composition contains (A) a metal compound containing at least one metal selected from the group consisting of Ti, Zr, and Hf, (B) a cross-linking agent having two or more and four or less cyclic ether structures having 2-13 carbon atoms in the molecule, and (C) a solvent.

Description

Technical Field

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

[0002] With the high integration and high speed of LSI, the miniaturization of pattern size is progressing rapidly. With this miniaturization, photolithography technology has achieved the formation of fine patterns by shortening the wavelength of the light source and appropriately selecting the resist composition for it. The center of this is the positive photoresist composition used in a single layer. The single-layer positive photoresist composition has a skeleton in the resist resin that has etching resistance to dry etching by chlorine-based or fluorine-based gas plasma, and has a switching mechanism in which the exposed part dissolves, thereby dissolving the exposed part to form a pattern, and using the remaining resist pattern as an etching mask to dry etch the processed substrate.

[0003] However, if the thickness of the photoresist film used is maintained and it is miniaturized, that is, if the pattern width is made smaller, the resolution performance of the photoresist film is reduced. In addition, if the photoresist film is to be patterned by a developer, the so-called aspect ratio becomes too large, resulting in a problem of pattern collapse. Therefore, as the pattern is miniaturized, the photoresist film is made thinner.

[0004] On the other hand, in the processing of the processed substrate, a method of processing the substrate by dry etching is usually used, in which a photoresist film with a pattern is used as an etching mask, but in reality, there is no dry etching method that can obtain complete etching selectivity between the photoresist film and the processed substrate. Therefore, there is a problem that the photoresist film is easily damaged and collapsed during the processing of the substrate, and the resist pattern cannot be correctly transferred to the processed substrate. Therefore, with the miniaturization of the pattern, a higher dry etching resistance is required for the resist composition. However, on the other hand, in order to improve the resolution, the resin used in the photoresist composition is required to have a small light absorption at the exposure wavelength. Therefore, as the exposure light is i-ray, KrF, ArF, the short wavelength, the resin also changes to a resin with a novolac resin, polyhydroxystyrene, and an aliphatic polycyclic skeleton. In reality, the etching speed of the dry etching conditions during substrate processing is fast, and the recent photoresist composition with high resolution has a tendency to weaken the etching resistance.

[0005] In view of this situation, it becomes necessary to dry-etch the substrate to be processed with a thinner photoresist film having weaker etching resistance, and it is urgent to secure the materials and processes in this processing step.

[0006] One method for solving such a problem is a multilayer resist method, in which a resist interlayer having an etching selectivity different from that of a photoresist film (i.e., a resist upper layer film) is inserted between the resist upper layer film and a substrate to be processed, and after the resist upper layer film has a pattern, the resist upper layer film pattern is used as a dry etching mask to transfer the pattern to the resist interlayer film by dry etching, and the resist interlayer film is further used as a dry etching mask to transfer the pattern to the substrate to be processed by dry etching.

[0007] As one of the multilayer resist methods, there is a three-layer resist method that can be performed using a general resist composition used in the single-layer resist method. The three-layer resist method is, for example, to form an organic film made of a novolac resin or the like as a resist lower film on a substrate to be processed, to form a silicon-containing resist intermediate film thereon as a resist intermediate film, and to form a normal organic photoresist film thereon as a resist upper film. When dry etching is performed by fluorine-based gas plasma, the organic resist upper film has a good etching selectivity ratio with respect to the silicon-containing resist intermediate film, so the resist upper film pattern can be transferred to the silicon-containing resist intermediate film by dry etching by fluorine-based gas plasma. According to this method, even if a resist composition that is difficult to form a pattern having a film thickness sufficient for directly processing a substrate to be processed or a resist composition that does not have sufficient dry etching resistance for processing a substrate is used, as long as the pattern can be transferred to a silicon-containing resist intermediate film (resist intermediate film) and then the pattern transfer is performed by dry etching using oxygen or hydrogen gas plasma, a pattern of an organic film (resist underlayer film) made of novolac resin or the like having sufficient dry etching resistance for a substrate processing tool can be obtained. As resist underlayer films such as those described in Patent Document 1, many are known.

[0008] On the other hand, in recent years, the miniaturization of DRAM memory has accelerated, and the need for further improvement of dry etching resistance and resist underlayer films with excellent filling and planarization characteristics has increased. As coating-type resist underlayer film (organic film) materials with excellent filling and planarization characteristics, for example, those described in Patent Document 2 are reported, but considering the use in the advanced generation, there are doubts about dry etching resistance, and the application of conventional coating-type resist underlayer film materials is approaching the limit.

[0009] In order to solve the above problems, the development of materials containing metal elements used in resist underlayer films has been studied. Patent Document 3 reports that materials using Ti compounds have excellent dry etching resistance to CHF3 / CF4 gas and CO2 / N2 gas.

[0010] On the other hand, as a problem when using metal compounds in resist underlayer films, embedding properties can be cited. Patent document 3 does not mention the embedding properties, but generally speaking, metal oxide compounds have large thermal shrinkage during baking, which will lead to significant deterioration of the filling properties after high-temperature baking, so there is a suspicion that they are insufficient as resist underlayer film materials that require high-level planarization properties, embedding properties, and heat resistance properties. Patent documents 4 and 5 report that metal compounds modified with specific ligands have excellent embedding properties, but the baking temperature for the embedding property evaluation is a low temperature of 150°C, which is suspected to be insufficient as resist underlayer films that require heat resistance (for example, properties for heat treatment performed after the resist underlayer film is formed).

[0011] Prior art literature

[0012] Patent Literature

[0013] [Patent Document 1] Japanese Patent Application Publication No. 2004-205685

[0014] [Patent Document 2] Japanese Patent No. 6714493

[0015] [Patent Document 3] Japanese Patent No. 6189758

[0016] [Patent Document 4] Japanese Patent No. 6786391

[0017] [Patent Document 5] Japanese Patent No. 7050137 Summary of the invention

[0018] [Problems to be solved by the invention]

[0019] The present invention is created in light of the above situation, and its purpose is to provide a metal-containing film-forming composition that has excellent dry etching resistance compared to conventional organic underlayer film materials and has a high degree of filling / planarization properties, and a pattern forming method using the composition for resist underlayer film materials, etc.

[0020] [Methods to solve the problem]

[0021] In order to solve the above problems, the present invention provides a metal-containing film-forming composition comprising:

[0022] (A) a metal compound containing at least one metal selected from the group consisting of Ti, Zr, and Hf,

[0023] (B) a cross-linking agent containing 2 to 13 carbon cyclic ether structures in the molecule, and

[0024] (C) Solvent.

[0025] According to such a metal-containing film-forming composition, the heat shrinkage of the metal compound during baking can be suppressed due to the reaction between the metal compound and the crosslinking agent, so that a metal-containing film (resist underlayer film) having excellent embedding properties can be provided.

[0026] The cross-linking agent (B) preferably has two or more epoxy groups or oxetanyl groups in the molecule.

[0027] Such a cross-linking agent improves the reactivity with the metal compound, and thus can provide a resist underlayer film having a more excellent embedding property.

[0028] The cross-linking agent (B) is preferably any one of the organic compounds represented by the following formula (1).

[0029] [Chemistry 1]

[0030]

[0031] (In the above formula (1), X is an m-valent organic group having 1 to 50 carbon atoms, L is a carbonyl group or a divalent organic group having 1 to 10 carbon atoms, R1 and R2 are each independently a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms, and R 1a is an alicyclic hydrocarbon group having 3 to 10 carbon atoms, l represents 0 or 1, and m represents 2 to 4.

[0032] Such a cross-linking agent further improves the reactivity with the metal compound, and thus can provide a resist underlayer film having a more excellent embedding property.

[0033] X in the above formula (1) is preferably an m-valent organic group containing one or more of a quaternary carbon atom, an aromatic ring, an alicyclic hydrocarbon, or a heterocyclic ring.

[0034] Such a cross-linking agent has excellent heat resistance, and thus promotes the reaction with the metal compound during baking, thereby further improving the embedding property of the metal-containing film-forming composition.

[0035] X in the above formula (1) is preferably any one of the following structures.

[0036] [Chemistry 2]

[0037]

[0038] (In the above formula, n is 1 to 5, r is 0 or 1, s is 1 or 2, R3 and R4 are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms which may contain a halogen atom, R5 is a hydrogen atom, a hydroxyl group or an alkyl group having 1 to 10 carbon atoms, R6 and R7 are each independently a hydrogen atom, a hydroxyl group or an organic group having 1 to 10 carbon atoms which contains an alkyl group, an alkylene group or an alkynyl group, R8 is a hydrogen atom, a hydroxyl group or an organic group having 1 to 10 carbon atoms which contains an alkyl group, an alkylene group or an alkynyl group, and * represents a bond to L. The carbon atoms in the aromatic ring of the above formula may have a hydroxyl group, a carboxyl group, a vinyl group, an ethynyl group, an amino group, a thioether group, or an alkyl group having 1 to 10 carbon atoms which may contain these as substituents.)

[0039] Such a cross-linking agent has excellent thermal fluidity and heat resistance, and thus can further improve the embedding property of the metal-containing film-forming composition.

[0040] The above-mentioned (A) metal compound is preferably a metal compound represented by the following formula (2).

[0041] [Chemistry 3]

[0042] Ln a MX b (2)

[0043] (wherein, M is any one of Ti, Zr, and Hf. Ln is independently a monodentate ligand or a polydentate ligand having 1 to 30 carbon atoms, and Xn is independently selected from a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, -NR a R b Hydrolyzable group. a and R b Each is independently a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. a+b=4, where a and b are integers of 0 to 4.

[0044] By using such a metal compound, a metal-containing film-forming composition that exhibits excellent resistance to dry etching using oxygen gas and fluorine gas can be formed.

[0045] The above formula (2) is preferably a structure of the following formula (3).

[0046] [Chemistry 4]

[0047] M(OR 1A )4 (3)

[0048] (wherein, M is Ti, Zr, or Hf, R 1A It is a monovalent organic group having 1 to 20 carbon atoms.

[0049] A metal compound having such a structure is preferable from the viewpoint of productivity and raw material availability.

[0050] The above-mentioned (A) metal compound is preferably a reaction product of a compound derived from the metal compound represented by the above-mentioned formula (2) and an organic compound having 1 to 30 carbon atoms and containing at least one crosslinking group represented by the following general formulas (a-1) to (a-4), (b-1) to (b-4), (c-1) to (c-3) and (d-1) to (d-2).

[0051] [Chemistry 5]

[0052]

[0053] (In the above general formulas (a-1) to (a-4), R a are independently a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, q represents 0 or 1, and * represents a bonding portion.

[0054] [Chemistry 6]

[0055]

[0056] (In the above general formula, R b are independently a hydrogen atom or a methyl group, which may be the same or different from each other in the same formula, c It is hydrogen or a substituted or unsubstituted saturated or unsaturated monovalent organic group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted aralkyl group having 7 to 31 carbon atoms, and * represents a bonding part. )

[0057] [Chemistry 7]

[0058]

[0059] (In the above general formulae (c-1) to (c-3), Y1 is independently a divalent organic group having 1 to 20 carbon atoms, R is a hydrogen atom, a substituted or unsubstituted saturated or unsaturated monovalent organic group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted aralkyl group having 7 to 31 carbon atoms, R d Each of the following general formula (c-4) is independently an organic group in which the protective group is removed by the action of one or both of acid and heat to generate one or more hydroxyl groups or carboxyl groups, and * represents a bonding part.

[0060] [Chemistry 8]

[0061]

[0062] (In the above general formula (c-4), R e It is an organic group whose protecting group is removed by the action of either acid, heat or both, and * represents the bonding part with Y1. )

[0063] [Chemistry 9]

[0064]

[0065] (Where R f It is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and * represents a bonding part. )

[0066] By including such a crosslinking group, the reactivity with the crosslinking agent can be improved, and the volume shrinkage during baking can be further alleviated. Therefore, even after high-temperature baking, a metal-containing film-forming composition having excellent planarization and filling properties can be provided.

[0067] The amount of the cross-linking agent (B) added is preferably 5 to 100 parts by mass based on 100 parts by mass of the metal compound (A).

[0068] If the added amount is such, a metal-containing film having excellent filling properties for uneven substrates and a small amount of outgassing during baking can be provided.

[0069] The solvent (C) is preferably 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.

[0070] By including such a high boiling point solvent, the self-crosslinking of the metal compound that is the cause of the gap generation can be suppressed. In addition, the coexisting solvent during film formation contributes to the improvement of the thermal fluidity of the metal-containing film-forming composition and the reduction of defects caused by drying, so that a suitable metal-containing film can be formed. In addition, the boiling point in this specification is a value at 1 atmosphere (1013hPa).

[0071] In addition, the present invention provides a pattern forming method, which is a method for forming a pattern on a processed substrate, comprising the following steps:

[0072] (I-1) After applying the metal-containing film-forming composition on a substrate to be processed, heat treatment is performed to form a metal-containing film.

[0073] (I-2) forming a resist upper layer film on the metal-containing film using a photoresist material,

[0074] (I-3) after exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0075] (I-4) using the patterned resist upper layer film as a mask, transferring the pattern to the metal-containing film by dry etching, and

[0076] (I-5) Using the patterned metal-containing film as a mask, the substrate to be processed is processed to form a pattern on the substrate to be processed.

[0077] By using the pattern forming method using the above-mentioned two-layer resist process, a fine pattern can be formed on a workpiece (workpiece substrate).

[0078] In addition, the present invention provides a pattern forming method, which is a method for forming a pattern on a processed substrate, comprising the following steps:

[0079] (II-1) forming a resist underlayer film on a substrate to be processed,

[0080] (II-2) coating the metal-containing film-forming composition on the resist underlayer film and then performing a heat treatment to form a metal-containing film;

[0081] (II-3) forming a resist upper layer film on the metal-containing film using a photoresist material,

[0082] (II-4) After exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0083] (II-5) using the patterned resist upper layer film as a mask, transferring the pattern to the metal-containing film by dry etching,

[0084] (II-6) using the metal-containing film having the transferred pattern as a mask, transferring the pattern to the resist underlayer film by dry etching,

[0085] (II-7) The substrate to be processed is processed using the patterned resist underlayer film as a mask to form a pattern on the substrate to be processed.

[0086] By using the pattern forming method using the three-layer resist process, a fine pattern can be formed on a workpiece with high precision.

[0087] As described above, the present invention can use the above-mentioned metal-containing film-forming composition to directly form a metal-containing film on the processed substrate as a resist underlayer film, and can also form a metal-containing film separately after forming a resist underlayer film on the processed substrate.

[0088] In addition, the present invention provides a pattern forming method, which is a method for forming a pattern on a processed substrate, comprising the following steps:

[0089] (III-1) After applying the metal-containing film-forming composition on a substrate to be processed, heat treatment is performed to form a metal-containing film.

[0090] (III-2) forming a silicon-containing resist intermediate film on the metal-containing film,

[0091] (III-3) forming a resist upper layer film on the silicon-containing resist intermediate film using a photoresist material,

[0092] (III-4) after exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0093] (III-5) using the patterned resist upper layer film as a mask, transferring the pattern to the silicon-containing resist intermediate film by dry etching,

[0094] (III-6) using the transferred patterned silicon-containing resist intermediate film as a mask, transferring the pattern to the metal-containing film by dry etching, and

[0095] (III-7) The substrate to be processed is processed using the patterned metal-containing film as a mask to form a pattern on the substrate to be processed.

[0096] By using the pattern forming method using the three-layer resist process, a fine pattern can be formed on a workpiece with high precision.

[0097] In addition, the present invention provides a pattern forming method, which is a method for forming a pattern on a processed substrate, comprising the following steps:

[0098] (IV-1) After applying the metal-containing film-forming composition on a substrate to be processed, heat treatment is performed to form a metal-containing film.

[0099] (IV-2) forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxide nitride film on the metal-containing film,

[0100] (IV-3) forming an organic thin film on the inorganic hard mask intermediate film,

[0101] (IV-4) forming a resist upper layer film on the organic thin film using a photoresist material,

[0102] (IV-5) After exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0103] (IV-6) using the patterned resist upper film as a mask, transferring the pattern to the organic thin film and the inorganic hard mask intermediate film by dry etching,

[0104] (IV-7) using the inorganic hard mask intermediate film to which the pattern has been transferred as a mask, transferring the pattern to the metal-containing film by dry etching, and

[0105] (IV-8) The substrate to be processed is processed using the patterned metal-containing film as a mask to form a pattern on the substrate to be processed.

[0106] By using the pattern forming method using the above-mentioned four-layer resist process, a fine pattern can be formed on a workpiece with high precision.

[0107] At this time, the inorganic hard mask intermediate film is preferably formed by a CVD method or an ALD method.

[0108] When the inorganic hard mask is formed by a CVD method or an ALD method, a fine pattern can be formed on a workpiece with high precision.

[0109] In addition, the present invention provides a pattern forming method, which is a method for forming a pattern on a processed substrate, comprising the following steps:

[0110] (V-1) After applying the metal-containing film-forming composition on a substrate to be processed, heat treatment is performed to form a metal-containing film.

[0111] (V-2) forming an organic intermediate film on the metal-containing film,

[0112] (V-3) forming a silicon-containing resist interlayer film, or a combination of an inorganic hard mask interlayer film selected from silicon oxide film, silicon nitride film, and silicon oxide nitride film and an organic thin film on the organic interlayer film,

[0113] (V-4) forming a resist upper film on the silicon-containing resist intermediate film or the organic film using a photoresist material,

[0114] (V-5) After exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0115] (V-6) using the patterned resist upper film as a mask, transferring the pattern to the silicon-containing resist intermediate film, or the organic thin film and the inorganic hard mask intermediate film by dry etching,

[0116] (V-7) using the transferred pattern of the silicon-containing resist interlayer or the inorganic hard mask interlayer as a mask, and transferring the pattern to the organic interlayer by dry etching.

[0117] (V-8) using the organic intermediate film as a mask, transferring a pattern to the metal-containing film by dry etching, and

[0118] (V-9) The substrate to be processed is processed using the patterned metal-containing film as a mask to form a pattern on the substrate to be processed.

[0119] By using the pattern forming method using the multilayer resist process, a fine pattern can be formed on a workpiece with high precision.

[0120] In addition, the present invention provides a tone reversal pattern forming method, which is a method for forming a pattern on a processed substrate, comprising the following steps:

[0121] (VI-1) forming a resist underlayer film on a substrate to be processed,

[0122] (VI-2) forming a silicon-containing resist intermediate film, or a combination of an inorganic hard mask intermediate film selected from silicon oxide film, silicon nitride film, and silicon oxide nitride film and an organic thin film on the resist underlayer film,

[0123] (VI-3) forming a resist upper film using a photoresist material on the silicon-containing resist intermediate film or the combination of the inorganic hard mask intermediate film and the organic thin film,

[0124] (VI-4) After exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0125] (VI-5) using the patterned resist upper film as a mask, transferring the pattern to the silicon-containing resist intermediate film, or the organic thin film and the inorganic hard mask intermediate film by dry etching,

[0126] (VI-6) using the transferred patterned silicon-containing resist interlayer film or inorganic hard mask interlayer film as a mask, transferring the pattern to the resist underlayer film by dry etching,

[0127] (VI-7) coating the metal-containing film-forming composition on the patterned resist underlayer film, and then performing a heat treatment to coat the metal-containing film, thereby filling the space between the resist underlayer film patterns with the metal-containing film.

[0128] (VI-8) etching back the metal-containing film covering the patterned resist underlayer film by chemical stripper or dry etching to expose the top surface of the patterned resist underlayer film;

[0129] (VI-9) removing the silicon-containing resist interlayer film or the inorganic hard mask interlayer film remaining on the top surface of the resist underlayer film by dry etching,

[0130] (VI-10) removing the patterned resist underlayer film whose surface is exposed by dry etching to form a reverse pattern of the original pattern on the metal-containing film,

[0131] (VI-11) The metal-containing film having the reverse pattern formed therein is used as a mask to process the substrate to form a reverse pattern on the substrate.

[0132] By using the pattern forming method using the above-mentioned reverse process, a fine pattern can be formed on the workpiece with higher precision.

[0133] [Effects of the Invention]

[0134] As described above, the metal-containing film-forming composition of the present invention is composed of (A) a metal compound, (B) a cross-linking agent having a cyclic ether structure having 2 to 13 carbon atoms and containing 2 or more and 4 or less in the molecule, and (C) a solvent. By the reaction between the (A) metal compound and the (B) cross-linking agent, the volume shrinkage of the metal compound that causes the gap can be alleviated, so that a resist underlayer film material having excellent planarization characteristics and filling characteristics can be provided even after high-temperature baking.

[0135] In particular, in the fine patterning process using the multilayer resist method in the semiconductor device manufacturing process, even on the processed substrate with a portion that is difficult to fill / flatten, such as a dense portion of a high-aspect-ratio fine pattern structure represented by a DRAM memory where miniaturization is progressing, filling can be performed without causing defects such as gaps or peeling. In addition, compared with the previous coating-type resist underlayer film material, it has excellent dry etching resistance, so compared with the resist underlayer film, it can form a fine pattern on the processed body with higher precision. BRIEF DESCRIPTION OF THE DRAWINGS

[0136] [ Figure 1 ] Figure 1 (A) to (F) are explanatory diagrams of an example (three-layer resist flow) of the pattern forming method of the present invention.

[0137] [ Figure 2 ] Figure 2 (G) to (P) are explanatory diagrams of an example of the tone reversal pattern forming method of the present invention (reversal of the SOC pattern in the three-layer resist process).

[0138] [ Figure 3 ] Figure 3 (Q) to (T) are explanatory diagrams of the landfill characteristic evaluation method. DETAILED DESCRIPTION

[0139] As described above, there is a search for a metal-containing film-forming composition having excellent filling properties and flatness for use in forming a resist underlayer film that can transfer a resist pattern to a processed substrate with higher precision in a fine patterning process using a multilayer resist method, and a pattern forming method using the composition.

[0140] The inventors have conducted in-depth research on conventional resist underlayer film materials, focusing on metal materials that exhibit excellent etching resistance. On the other hand, conventional metal compounds used to form resist underlayer films lack heat resistance and produce rapid volume shrinkage during baking, so it is difficult to fill and flatten the height difference of the processed substrate after high-temperature baking. Therefore, the inventors have imagined whether it is possible to suppress the volume shrinkage of the metal compound during baking by using additives.

[0141] With regard to the polyfunctional organic compounds used in the metal-containing film-forming composition, for example, there are reports that nitrogen-containing organic compounds having more than two hydroxyl groups contribute to the stability of the metal compounds in the composition (WO2020 / 241712). In addition, there are reports that polyols function as landfill aids (Japanese Patent Gazette No. 6810696). It is speculated that these additives have hydroxyl groups, so the state of the metal-containing film-forming composition is coordinated to the metal atom or free, and it is volatile or thermally decomposed during baking, so it is expected that the effect of improving the landfill property is weak. Japanese Patent Gazette No. 6810696 reports that the landfill property is improved by adding polyols, but the result of baking at 250°C does not discuss the landfill property at higher temperatures necessary for the formation of metal oxide films.

[0142] The inventors of the present invention believe that, since the state of the metal oxide film forming composition is not coordinated to the metal, the metal compound reacts with the polyfunctional organic compound during baking, thereby suppressing the rapid volume shrinkage of the metal compound, and no gaps are generated even during high-temperature baking, thereby being able to fill the height differences of the processed substrate.

[0143] The inventors of the present invention have repeatedly conducted more in-depth studies and found that, with respect to the multifunctional cross-linking group, if it is a cyclic ether structure with 2 to 13 carbon atoms, it can improve the reactivity with the metal compound during baking without damaging the stability of the metal-containing film-forming composition, and can form a metal-containing film with excellent embedding properties, thereby completing the present invention.

[0144] That is, the present invention is a metal-containing film-forming composition comprising:

[0145] (A) a metal compound containing at least one metal selected from the group consisting of Ti, Zr, and Hf,

[0146] (B) a cross-linking agent containing 2 to 13 carbon cyclic ether structures in the molecule, and

[0147] (C) Solvent.

[0148] Hereinafter, the present invention will be described in detail, but the present invention is not limited thereto.

[0149] <Metal-Containing Film-Forming Composition>

[0150] The metal-containing film-forming composition of the present invention is characterized by containing:

[0151] (A) a metal compound containing at least one metal selected from the group consisting of Ti, Zr, and Hf,

[0152] (B) a cross-linking agent containing 2 to 13 carbon cyclic ether structures in the molecule, and

[0153] (C) Solvent.

[0154] The above-mentioned (A) metal compound (hereinafter also referred to as “metal-containing film-forming compound”) can be used in a metal-containing film-forming composition used in semiconductor manufacturing, for example.

[0155] In addition, in the metal-containing film-forming composition of the present invention, (A) the metal compound, (B) the cross-linking agent, and (C) the solvent may be used alone or in combination of two or more. Furthermore, the metal-containing film-forming composition may also contain components other than the above-mentioned components (A), (B), and (C). Each component is described below.

[0156] <Metal Compounds>

[0157] The metal compound contained in the metal-containing film-forming composition of the present invention contains at least one metal atom selected from the group consisting of Ti, Zr, and Hf, and is preferably a compound having a metal-oxygen covalent bond.

[0158] By including such a metal, the refractive index of the metal-containing film after heat treatment can be increased, and a metal-containing film having excellent resistance to dry etching using oxygen gas and fluorine gas can be formed.

[0159] The lower limit of the content of the metal element atoms in the metal compound (A) is preferably 5 mass %, more preferably 10 mass %, further preferably 20 mass %, and particularly preferably 30 mass %. The upper limit of the above content is preferably 50 mass %. The content of the metal element atoms can be obtained by measuring using a thermogravimetric-thermal differential analyzer (TG / DTA).

[0160] If the ratio of the metal element is such, the refractive index of the metal-containing film-forming composition and the dry etching resistance to oxygen gas and fluorine gas can be further improved.

[0161] The metal atoms contained in the above-mentioned metal compound may be composed of atoms of one element or of two or more elements. Considering that the etching speed during the inorganic film etching transfer processing after the formation of a fine pattern is expected to be uniform within the surface at the nanoscale level, it is preferable that the metal compound be composed of atoms of one element.

[0162] By virtue of the metal compound containing a metal-oxygen atom bond, the metal-containing film formed from the metal-containing film-forming composition has excellent etching selectivity. The oxygen atom may be bonded to one metal atom or to multiple atoms, and a structure mainly containing two oxygen atoms bonded to a metal atom is more ideal. By virtue of a structure mainly containing two oxygen atoms bonded to a metal atom (covalent bond or coordination bond), the metal compound is made into a more linear structure such as -MOMO- (M is a specific metal atom), which can improve solvent solubility.

[0163] As the (A) metal compound of the present invention, a commercially available metal compound may be used, for example, a metal-containing compound having a hydrolyzable group (hereinafter referred to as (a) hydrolyzable metal-containing compound). In addition, the synthesis may be carried out by a method of performing a hydrolysis-condensation reaction of the (a) hydrolyzable metal-containing compound. That is, the (A) metal compound may be derived from the (a) hydrolyzable metal-containing compound. The "hydrolysis-condensation reaction" herein refers to a reaction in which the hydrolyzable group possessed by the (a) hydrolyzable metal-containing compound is hydrolyzed and converted into -OH, and the two obtained -OHs are dehydrated and condensed to form -O-.

[0164] As the (A) metal compound of the present invention, it is preferable to use the above-mentioned (a) hydrolyzable metal-containing compound, the hydrolysis-condensation reaction product of (a) the hydrolyzable metal-containing compound, or the compound formed by reacting these compounds with a substance that can become a monodentate ligand or a polydentate ligand. It is more preferable to use the hydrolysis-condensation reaction product of (a) the hydrolyzable metal-containing compound or the compound formed by reacting the hydrolysis-condensation reaction product of (a) the hydrolyzable metal-containing compound with a substance that can become a monodentate ligand or a polydentate ligand.

[0165] If it is such a metal compound (A), it reacts well with the cross-linking agent (B) during baking to form a metal-containing film with excellent embedding properties. In addition, from the perspective of dry etching resistance, it is more preferable to use a hydrolysis-condensation reaction product of a hydrolyzable metal-containing compound (a) or a compound formed by reacting a hydrolysis-condensation reaction product of a hydrolyzable metal-containing compound (a) with a ligand that can become a monodentate ligand or a polydentate ligand.

[0166] [(a) Hydrolyzable metal-containing compound]

[0167] The (a) hydrolyzable metal-containing compound is a metal compound (I) having a hydrolyzable group, a hydrolyzate of the metal compound (I), a hydrolysis condensate of the metal compound (I), or a combination thereof. The metal compound (I) can be used alone or in combination of two or more.

[0168] Examples of the metal compound (I) include a compound (I-1) represented by the following formula (2). By using such a metal compound (I-1), a stable compound (A) can be formed, and dry etching resistance can be improved.

[0169] [Chemistry 10]

[0170] Ln a MX b (2)

[0171] (wherein, M is any one of Ti, Zr, and Hf. Ln is independently a monodentate ligand or a multidentate ligand having 1 to 30 carbon atoms, and Xn is independently selected from a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, -NR a R b Hydrolyzable group. a and R b Each is independently a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. a+b=4, where a and b are integers of 0 to 4.

[0172] (Hydrolyzable Group)

[0173] Examples of the hydrolyzable group Xn in the general formula (2) include a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, and -NR a R b One or more of the following. a and R b Each independently represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms.

[0174] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0175] Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, and a tert-butoxy group.

[0176] Examples of the carboxylate group include an acetate group, a propionate group, a butyrate group, an n-hexanecarboxylate group, and an n-octanecarboxylate group.

[0177] Examples of the acyloxy group include an acetoxy group, an ethyryloxy group, a propionyloxy group, a butyryloxy group, a tert-butyryloxy group, a tert-valeryloxy group, a n-hexanecarbonyloxy group, and a n-octanecarbonyloxy group.

[0178] As the above-NR a R b , for example, unsubstituted amino, methylamino, dimethylamino, diethylamino, dipropylamino and the like can be mentioned.

[0179] The hydrolyzable group Xn is more preferably an alkoxy group, more preferably an isopropoxy group, an n-butoxy group, or a tert-butoxy group.

[0180] Examples of the ligand Ln in the general formula (2) include the following monodentate ligands or polydentate ligands.

[0181] (Single tooth matching)

[0182] Examples of the monodentate ligand include a hydroxy ligand (OH), a carboxyl ligand, an amide ligand, an amine ligand, an ammonia ligand (NH 3 ), and an olefin ligand.

[0183] Examples of the carboxyl ligand include a formate ligand (OOCH), an acetate ligand (OOCMe), a propionate ligand (OOCEt), and a butyrate ligand (OOCPr).

[0184] Examples of the amide ligand include unsubstituted amide ligand (NH2), methylamide ligand (NHMe), dimethylamide ligand (NMe2), diethylamide ligand (NEt2), and dipropylamide ligand (NPr2).

[0185] Examples of the amine ligand include pyridine, trimethylamine ligand, piperidine ligand and the like.

[0186] Examples of the olefin ligand include chain olefins such as ethylene and propylene, and cyclic olefins such as cyclopentene, cyclohexene and norbornene.

[0187] (Multi-toothed ligand)

[0188] Examples of the polydentate ligand include a ligand derived from a hydroxy acid ester, a ligand derived from a β-diketone, a ligand derived from a β-ketoester, a ligand derived from an α,α-dicarboxylate, a hydrocarbon having a π bond, and a diphosphine.

[0189] Examples of the hydroxy acid ester include glycolic acid ester, lactic acid ester, 2-hydroxycyclohexane-1-carboxylic acid ester, and salicylic acid ester.

[0190] Examples of the β-ketoester include acetoacetate, α-alkyl-substituted acetoacetate, β-ketovalerate, benzoyl acetate, and 1,3-acetone dicarboxylate.

[0191] Examples of the β-diketone include acetylacetone, methyl acetylacetone, and ethyl acetylacetone.

[0192] Examples of the α,α-dicarboxylic acid esters include malonic acid diesters, α-alkyl-substituted malonic acid diesters, α-cycloalkyl-substituted malonic acid diesters, and α-aryl-substituted malonic acid diesters.

[0193] Examples of the hydrocarbon having a π bond include chain dienes such as butadiene and isoprene, cyclic dienes such as cyclopentadiene, methylcyclopentadiene, pentamethylcyclopentadiene, cyclohexadiene, and norbornadiene, and aromatic hydrocarbons such as benzene, toluene, xylene, hexamethylbenzene, naphthalene, and indene.

[0194] Examples of the diphosphine include 1,1-bis(diphenylphosphino)methane, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl, and 1,1′-bis(diphenylphosphino)ferrocene.

[0195] In the above general formula (2), a+b=4, and a and b are integers of 0 to 4. a is preferably 0 to 3, more preferably 0 to 2, further preferably 1 to 2, and particularly preferably 2. b is preferably 2 to 4, more preferably 2 to 3, and further preferably 2. By setting a and b to the above ranges, the stability of the metal compound can be improved.

[0196] Examples of the (a) hydrolyzable metal-containing compound include: titanium-containing compounds such as diisopropoxybis(2,4-pentanedione)titanium(IV), tetra-n-butoxytitanium(IV), tetra-n-propoxytitanium(IV), tri-n-butoxymonostearatetitanium(IV), butoxide titanium(IV) oligomer, aminopropyltrimethoxytitanium(IV), triethoxymono(2,4-pentanedione)titanium(IV), tri-n-propoxymono(2,4-pentanedione)titanium(IV), triisopropoxymono(2,4-pentanedione)titanium, and di-n-butoxybis(2,4-pentanedione)titanium(IV); and zirconium-containing compounds such as dibutoxybis(ethylacetoacetate)zirconium(IV), di-n-butoxybis(2,4-pentanedione)zirconium(IV), tetra-n-butoxyzirconium(IV), tetra-n-propoxyzirconium(IV), tetraisopropyltrimethoxytitanium(IV), triethoxymono(2,4-pentanedione)titanium(IV), tri-n-propoxymono(2,4-pentanedione)titanium(IV), and di-n-butoxybis(2,4-pentanedione)titanium(IV). Examples of the hafnium-containing compound include trimethoxy zirconium (IV) propoxide, triethoxy zirconium (IV) aminopropyl, 2-(3,4-epoxycyclohexyl)ethyl trimethoxy zirconium (IV), γ-glycidoxypropyl trimethoxy zirconium (IV), 3-isocyanopropyl trimethoxy zirconium (IV), triethoxy (2,4-pentanedione) zirconium (IV), tri-n-propoxy (2,4-pentanedione) zirconium (IV), triisopropoxy (2,4-pentanedione) zirconium (IV), tri(3-methacryloxypropyl)methoxy zirconium (IV), and tri(3-acryloxypropyl)methoxy zirconium (IV). Examples of the hafnium-containing compound include diisopropoxybis(2,4-pentanedione) hafnium (IV), tetrabutoxy hafnium (IV), tetraisopropoxy hafnium (IV), tetraethoxy hafnium (IV), and dichlorobis(cyclopentadienyl) hafnium (IV).

[0197] From the viewpoint of raw material availability, the metal compound preferably has a structure represented by the following general formula (3).

[0198] [Chemistry 11]

[0199] M(OR 1A )4 (3)

[0200] (where M is the same as above, R 1A It is a monovalent organic group having 1 to 20 carbon atoms.

[0201] In the above general formula (3), R 1A It is a monovalent organic group having 1 to 20 carbon atoms, preferably methyl, ethyl, n-propyl, isopropyl, n-butyl or tert-butyl, more preferably isopropyl, n-butyl or tert-butyl.

[0202] As described above, the (A) metal compound may be the (a) hydrolyzable metal-containing compound itself or a hydrolysis-condensation reaction product thereof, or may be a compound obtained by further reacting the compound as described below.

[0203] (A) During the synthesis reaction of the metal compound, in addition to the (a) hydrolyzable metal-containing compound, a compound capable of obtaining a monodentate ligand or a polydentate ligand in the metal compound (hereinafter referred to as (b) ligand-forming compound) may be added.

[0204] As the above-mentioned (b) ligand-forming compound, in addition to organic compounds that can obtain hydroxyl ligands, carboxyl ligands, amide ligands, amine ligands, amino ligands, olefin ligands, etc. listed as Ln in the above-mentioned general formula (2), organic compounds that can obtain ligands derived from hydroxy acid esters, ligands derived from β-diketones, ligands derived from β-ketoesters, ligands derived from α,α-dicarboxylates, etc., compounds having multiple hydroxyl groups can also be listed.

[0205] The metal compound (A) can be obtained by reacting a compound derived from the metal compound represented by the above formula (2) with at least one organic compound having 1 to 30 carbon atoms and containing a crosslinking group represented by the general formulae (a-1) to (a-4), (b-1) to (b-4), (c-1) to (c-3), and (d-1) to (d-2) described below. In this manner, a crosslinking group can be introduced into the component (A).

[0206] Furthermore, the (b) ligand-forming compound may also be an organic compound having 1 to 30 carbon atoms and containing at least one cross-linking group represented by any one of the cross-linking groups represented by the following general formulas (a-1) to (a-4), (b-1) to (b-4), (c-1) to (c-3) and (d-1) to (d-2).

[0207] [Chemistry 12]

[0208]

[0209] (In the above general formulas (a-1) to (a-4), R a are independently a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, q represents 0 or 1, and * represents a bonding portion.

[0210] [Chemistry 13]

[0211]

[0212] (In the above general formula, R b are independently a hydrogen atom or a methyl group, which may be the same or different from each other in the same formula, c It is hydrogen, or a substituted or unsubstituted saturated or unsaturated monovalent organic group having 1 to 20 carbon atoms, 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, and * represents a bonding part. )

[0213] [Chemistry 14]

[0214]

[0215] (In the above general formulae (c-1) to (c-3), Y1 is independently a divalent organic group having 1 to 20 carbon atoms, R is a hydrogen atom, a substituted or unsubstituted saturated or unsaturated monovalent organic group having 1 to 20 carbon atoms, 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, R d They are independently organic groups represented by the following general formula (c-4), which undergo the removal of the protecting group by the action of either or both of an acid or heat to generate one or more hydroxyl groups or carboxyl groups, and * represents a bonding part.

[0216] [Chemistry 15]

[0217]

[0218] (In the above general formula (c-4), R e It is an organic group whose protecting group is removed by the action of either acid, heat or both, and * represents the bonding part with Y1. )

[0219] [Chemistry 16]

[0220]

[0221] (Where R f It is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and * represents a bonding part. )

[0222] The metal-containing film-forming compound contains at least one crosslinking group represented by any one of the general formulae (a-1) to (a-4), (b-1) to (b-4), (c-1) to (c-3), and (d-1) to (d-2), thereby improving the thermal curability of the metal compound. The heat resistance of the metal compound is improved by organic crosslinking between ligands, thereby further promoting the reaction with the crosslinking agent during baking.

[0223] Considering the productivity and stability of the metal-containing film-forming compound, the above-mentioned (b) ligand-forming compound is preferably a compound that can obtain a carboxyl ligand, a compound that can obtain a β-diketone ligand, or a compound having multiple hydroxyl groups. These can be used alone or in combination of two or more.

[0224] Examples of the compound capable of acquiring a carboxyl ligand include compounds represented by the following general formula (4).

[0225] [Chemistry 17]

[0226]

[0227] (where p is 0 or 1. When p is 1, X 1 is a divalent organic group having 2 to 20 carbon atoms, W is an alkoxy group having 1 to 10 carbon atoms, the following general formula (4-A), or any of the crosslinking groups represented by the above general formulas (b-1) to (b-4). When p is 0, X 1 It is a monovalent organic group having 8 to 30 carbon atoms and a crosslinking group and an aromatic ring containing any of the structures represented by the above general formulae (a-2) and (a-3).

[0228] [Chemistry 18]

[0229]

[0230] In the above general formula (4-A), Y is a saturated or unsaturated divalent organic group having 1 to 20 carbon atoms, and R A Any one of the structures represented by the above general formulae (a-1) to (a-4), h represents 1 to 6, and * represents a bond to the carbon atom of the carbonyl group.

[0231] If the metal-containing film-forming compound contains a carboxyl ligand having such a structure, the heat resistance during baking is improved, so that the reaction with the cross-linking agent (B) can be easily promoted, and a metal-containing film with better embedding properties can be formed.

[0232] In the above general formula (4), p is preferably 1, and W is a structure represented by the following general formula (4-B).

[0233] [Chemistry 19]

[0234]

[0235] (In the above general formula (4-B), R A1 is the structure represented by the above general formula (a-1), R A2 is any of the structures represented by the above general formula (a-2) or (a-3), Z is any of an oxygen atom or a secondary amine, La is a divalent hydrocarbon group having 1 to 10 carbon atoms, and R A3 It is a saturated or unsaturated divalent organic group having 1 to 20 carbon atoms or 2 to 20 carbon atoms, t1 is 1 to 6, s1 is 0 to 5, t1+s1 is 1 to 6, r1 is 1 to 10, u is 0 or 1, m1 is 0 or 1, and * represents a bond to the carbon atom of the carbonyl group.

[0236] If the metal-containing film-forming compound contains a carboxyl ligand having such a structure, the heat resistance during baking is improved, so that the reaction with the cross-linking agent (B) can be easily promoted, and a metal-containing film with better embedding properties can be formed.

[0237] In the above general formula (4), preferably, p is 1, W is an alkoxy group having 1 to 10 carbon atoms, and X 1 Any one of the structures represented by the following general formula (4-C).

[0238] [Chemistry 20]

[0239]

[0240] (In the formula, * represents the bond to the carbon atom of the carbonyl group.)

[0241] If the metal-containing film-forming compound contains a carboxyl ligand having such a structure, the heat resistance during baking is improved, so that the reaction with the cross-linking agent (B) can be easily promoted, and a metal-containing film with better embedding properties can be formed.

[0242] Alternatively, preferably, in the above general formula (4), p is 0, X 1 Any one of the structures represented by the following formula (4-D).

[0243] [Chemistry 21]

[0244]

[0245] (In the formula, R2 is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, and * represents a bond to the carbon atom of the carbonyl group. However, the above R2 is applicable only to the above formula.)

[0246] Other examples of the compound derived from a carboxyl ligand include compounds represented by the following general formula (5).

[0247] [Chemistry 22]

[0248]

[0249] (Where X 2 is a divalent organic group having 1 to 31 carbon atoms, R 6A It is any one of the above general formulas (c-1) to (c-3).

[0250] In the above general formula (5), X 2 It is a divalent organic group having 1 to 31 carbon atoms, and is more preferably a saturated hydrocarbon group having 1 to 20 carbon atoms or an unsaturated hydrocarbon group having 2 to 20 carbon atoms from the viewpoint of thermosetting properties.

[0251] In the above general formulas (c-1) to (c-3), Y1 is independently a divalent organic group having 1 to 20 carbon atoms, which may be a substituted or unsubstituted saturated divalent organic group having 1 to 20 carbon atoms or an unsaturated divalent organic group having 2 to 20 carbon atoms, for example, it is preferably a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or a substituted or unsubstituted arylalkyl group having 7 to 20 carbon atoms, and Y1 is preferably a saturated hydrocarbon group having 1 to 20 carbon atoms or an unsaturated hydrocarbon group having 2 to 20 carbon atoms.

[0252] If Y1 in the above general formulas (c-1) to (c-3) is a saturated hydrocarbon group having 1 to 20 carbon atoms or an unsaturated hydrocarbon group having 2 to 20 carbon atoms, the heat curing property of the metal-containing film-forming compound as a metal-containing film-forming composition can be further improved. In addition, it is also more desirable from the perspective of raw material availability.

[0253] Specifically, the following structures can be exemplified as examples of Y1, but the present invention is not limited to these.

[0254] [Chemistry 23]

[0255]

[0256] (*1 is the bond with oxygen or nitrogen atom, *2 is the bond with R d The bonding part.)

[0257] In the above general formula (c-4), R e The organic group is an organic group from which a thermally acid-labile group leaves by the action of either acid or heat or both, and is preferably a tertiary hydrocarbon group or a group that forms an acetal structure together with an adjacent oxygen atom, and is particularly preferably a tertiary hydrocarbon group. The tertiary hydrocarbon group is preferably a group having 4 to 20 carbon atoms, and more preferably a group having a small number of carbon atoms.

[0258] If the metal-containing film-forming compound contains a carboxyl ligand having such a structure, the heat resistance during baking is improved, so that the reaction with the cross-linking agent (B) can be easily promoted, and a metal-containing film with better embedding properties can be formed.

[0259] Examples of the compound capable of obtaining a ligand derived from β-diketone include compounds represented by the following general formula (6).

[0260] [Chemistry 24]

[0261]

[0262] (Where R 6A ~R 6D A monovalent organic group having 1 to 20 carbon atoms and which may contain a crosslinking group represented by any of the crosslinking groups represented by the above general formulae (a-1) to (a-4), (b-1) to (b-4) and (d-1) to (d-2).

[0263] The compound of the general formula (6) is preferably at least one crosslinking group represented by any of the general formulas (a-1) to (a-4), (b-1) to (b-4) and (d-1) to (d-2). Such a compound improves the heat resistance during baking, thus easily promoting the reaction with the crosslinking agent (B), and forming a metal-containing film with better embedding properties, which is more ideal.

[0264] In the above formula (6), R 6A and R 6D The monovalent organic group having 1 to 20 carbon atoms which may contain a crosslinking group represented by any of the above general formulae (a-1) to (a-4), (b-1) to (b-4) and (d-1) to (d-2) is preferably a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, a substituted or unsubstituted group containing an allyl group having 2 to 10 carbon atoms, a substituted or unsubstituted group containing an ethynyl group having 2 to 10 carbon atoms, or may contain the above The monovalent organic group having 1 to 20 carbon atoms in the crosslinking group represented by any one of the general formulae (a-1) to (a-4), (b-1) to (b-4) and (d-1) to (d-2) is more preferably a methyl group, an ethyl group, a phenyl group, an allyloxy group, a propargyloxy group, an alkoxy group having 1 to 10 carbon atoms, or may also contain a monovalent organic group having 1 to 20 carbon atoms in the crosslinking group represented by any one of the general formulae (a-1) to (a-4), (b-1) to (b-4) and (d-1) to (d-2).

[0265] In R 6A and R 6D When the crosslinking group represented by any of the general formulae (a-1) to (a-4), (b-1) to (b-4) and (d-1) to (d-2) is not present, a methyl group, a methoxy group or an ethoxy group is preferred.

[0266] R 6B and R 6CA monovalent organic group having 1 to 20 carbon atoms which may contain a crosslinking group represented by any of the general formulae (a-1) to (a-4), (b-1) to (b-4) and (d-1) to (d-2), preferably a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, a substituted or unsubstituted group containing an allyl group having 2 to 10 carbon atoms, or a substituted or unsubstituted group containing an ethynyl group having 2 to 10 carbon atoms , or a monovalent organic group having 1 to 20 carbon atoms containing a crosslinking group represented by any one of the general formulae (a-1) to (a-4), (b-1) to (b-4) and (d-1) to (d-2), more preferably a hydrogen atom, a methyl group, an ethyl group, a phenyl group, an allyloxy group, a propynyloxy group, or a monovalent organic group having 1 to 20 carbon atoms containing a crosslinking group represented by any one of the general formulae (a-1) to (a-4), (b-1) to (b-4) and (d-1) to (d-2). In addition, R 6B and R 6C They can also bond with each other to form a cyclic ether structure.

[0267] In R 6B When there is a substituent other than a hydrogen atom, R 6C Preferably, it is a hydrogen atom. Preferably, R 6B and R 6C At least one of R is a hydrogen atom. 6B and R 6C When no crosslinking group represented by any of the above general formulae (a-1) to (a-4), (b-1) to (b-4) and (d-1) to (d-2) is contained, R 6B and R 6C They are all hydrogen atoms.

[0268] Examples of the compound having a plurality of hydroxyl groups include diols represented by any of the following general formulae (7-A) to (7-C).

[0269] [Chemistry 25]

[0270]

[0271] (Where R 7a ~R 7b is a hydrogen atom, or a monovalent organic group having 1 to 20 carbon atoms which may also contain a crosslinking group represented by any of the general formulae (a-1) to (a-4) and (d-1) to (d-2), R 7c ~R 7gis a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms which may also contain a crosslinking group of any of the above general formulae (a-1) to (a-4), (b-1) to (b-4) and (d-1) to (d-2), and Y is a divalent organic group having 1 to 10 carbon atoms. 7a With R 7b They can also bond with each other to form unsaturated or saturated ring structures.)

[0272] The compounds of the general formulae (7-A) to (7-C) are preferably at least one crosslinking group represented by any one of the general formulae (a-1) to (a-4), (b-1) to (b-4) and (d-1) to (d-2). Such compounds are more desirable because they improve heat resistance during baking and can easily promote reaction with the crosslinking agent (B), thereby forming a metal-containing film with better embedding properties.

[0273] In the above formula (7-A), R 7a ~R 7b is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms which may contain a crosslinking group represented by any one of the general formulae (a-1) to (a-4) and (d-1) to (d-2), preferably a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, a substituted or unsubstituted allyl group having 2 to 10 carbon atoms, a substituted or unsubstituted ethynyl group having 2 to 10 carbon atoms, or a monovalent organic group having 1 to 20 carbon atoms which contains a crosslinking group represented by any one of the general formulae (a-1) to (a-4) and (d-1) to (d-2). In the case where the crosslinking group represented by any one of the general formulae (a-1) to (a-4) and (d-1) to (d-2) is not contained, R 7a and R 7b Preferably it is a hydrogen atom.

[0274] In the above formula (7-B), R 7c and R 7f It is a monovalent organic group having 1 to 20 carbon atoms, which may also contain a crosslinking group represented by any of the above general formulae (a-1) to (a-4), (b-1) to (b-4) and (d-1) to (d-2), preferably a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, and more preferably a hydrogen atom.

[0275] In the above formula (7-B), R 7dIt is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms and containing a crosslinking group represented by any one of the general formulae (a-1) to (a-4), (b-1) to (b-4) and (d-1) to (d-2), and more preferably a monovalent organic group having 1 to 20 carbon atoms and containing a crosslinking group represented by any one of the general formulae (a-1) to (a-4), (b-1) to (b-4) and (d-1) to (d-2). 7e is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms which may also contain a crosslinking group represented by any of the above general formulae (a-1) to (a-4), (b-1) to (b-4) and (d-1) to (d-2), more preferably a hydrogen atom or an alkyl or aryl group having 1 to 10 carbon atoms, and further preferably a hydrogen atom. 7d and R 7e They can also bond with each other to form a cyclic ether structure.

[0276] In the above formula (7-C), R 7g Preferably, it is a monovalent organic group having 1 to 20 carbon atoms and containing a crosslinking group represented by any of the general formulae (a-1) to (a-4), (b-1) to (b-4) and (d-1) to (d-2). Y is a divalent organic group having 1 to 10 carbon atoms, preferably a divalent hydrocarbon group having 1 to 10 carbon atoms, more preferably a hydrocarbon group having 1 to 5 carbon atoms in view of the availability of raw materials, further preferably a methylene group or an ethylene group, and particularly preferably an ethylene group.

[0277] If the metal-containing film-forming compound contains a multidentate ligand having such a structure, the heat resistance during baking is improved, so that the reaction with the cross-linking agent (B) can be easily promoted, and a metal-containing film with better embedding properties can be formed.

[0278] In the case where the metal-containing film-forming compound has a ligand from a (b) ligand-forming compound containing any one of the groups represented by the above formulae (a-1) to (a-4), (b-1) to (b-4), (c-1) to (c-3) and (d-1) to (d-2), the content of the ligand containing any one of the groups represented by the above formulae (a-1) to (a-4), (b-1) to (b-4), (c-1) to (c-3) and (d-1) to (d-2) is preferably 10 mol% to 90 mol% of the total content of the ligands coordinated to the metal atom, more preferably 20 mol% to 80 mol%, and further preferably 25 mol% to 75 mol%. The content of the ligands derived from the (b) ligand-forming compound not containing the groups represented by the formulae (a-1) to (a-4), (b-1) to (b-4), (c-1) to (c-3) and (d-1) to (d-2) is preferably 0 to 50 mol % of the total content of the ligands coordinated to the metal atom, more preferably 0 to 30 mol %. The content of the ligands other than the (b) ligand-forming compound, for example, the ligands derived from the alkoxy group having 1 to 10 carbon atoms, is preferably 0 to 90 mol % of the total content of the ligands coordinated to the metal atom, more preferably 20 to 80 mol %.

[0279] Furthermore, during the synthesis reaction of the (A) metal compound, a (c) silicon-containing compound may be added in addition to the (b) ligand-forming compound.

[0280] By substituting the hydrolyzable group of the (a) hydrolyzable metal-containing compound with the silicon-containing compound, the stability of the (A) metal compound in the metal-containing film-forming composition can be improved.

[0281] Examples of the silicon-containing compound include compounds having a structure represented by the following formula (8).

[0282] [Chemistry 26]

[0283]

[0284] (In (8) above, R 8A , R 8B and R 8C It is any one of organic groups having 1 to 30 carbon atoms, substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms, and aryl groups having 6 to 20 carbon atoms, which are crosslinking groups having any of the structures represented by the following general formulae (e-1) to (e-3).

[0285] [Chemistry 27]

[0286]

[0287] (In the above general formulae (e-1) to (e-3), R3 is hydrogen or a monovalent organic group having 1 to 10 carbon atoms, q represents 0 or 1, and * represents a bonding portion.)

[0288] As the silicon-containing compound, a compound represented by any of the following formulas is more preferred, and trimethylsilanol is more preferred from the viewpoint of productivity.

[0289] [Chemistry 28]

[0290]

[0291] When the (A) metal compound contains the (b) ligand-forming compound and the ligand derived from the (c) silicon-containing compound, the content of the (b) ligand-forming compound in the (A) metal compound is preferably 10 mol% to 100 mol%, more preferably 20 mol% to 80 mol%, and further preferably 25 mol% to 75 mol%, of the total ligands coordinated to the metal atom. The content of the ligand derived from the (c) silicon-containing compound is preferably 10 mol% to 90 mol%, more preferably 20 mol% to 80 mol%, and further preferably 25 mol% to 75 mol%, of the total ligands coordinated to the metal atom. The content of the ligands other than the (b) ligand-forming compound and the (c) silicon-containing compound, for example, the ligand derived from an alkoxy group having 1 to 10 carbon atoms, is preferably 0 mol% to 90 mol%, and further preferably 0 mol% to 75 mol%, of the total ligands coordinated to the metal atom.

[0292] The synthesis method of the (A) metal compound is not particularly limited. For example, the (A) hydrolyzable metal-containing compound can be obtained by reacting the alkoxy or acac metal with the ligand from the (B) ligand-forming compound using a metal alkoxide or acetylacetonate (acac) metal salt. The (A) hydrolyzable metal-containing compound can also be hydrolyzed and condensed, and then reacted with the ligand from the (B) ligand-forming compound. The (A) hydrolyzable metal-containing compound can also be reacted with the ligand from the (B) ligand-forming compound, and then hydrolyzed and condensed. In the case where it is difficult to control the hydrolysis and condensation, it can also be reacted with the ligand from the (B) ligand-forming compound in a non-aqueous environment. These should be appropriately adjusted according to the required properties of the (A) metal compound and the metal-containing film. In the case of having (c) a silicon-containing compound and a ligand derived from (b) a ligand-forming compound as ligands, it is more preferable to react (a) a hydrolyzable metal-containing compound with (c) a silicon-containing compound and then react it with the ligand derived from (b) a ligand-forming compound.

[0293] As a method for using (a) hydrolyzable metal-containing compounds to carry out hydrolysis-condensation reactions, for example, methods in which (a) hydrolyzable metal-containing compounds are subjected to hydrolysis-condensation reactions in a solvent containing water can be cited. In this case, other compounds with hydrolyzable groups can also be added in response to demand. In addition, as a catalyst for hydrolysis-condensation reactions, acids such as acetic acid can also be added. As the lower limit of the amount of water used in the hydrolysis-condensation reaction, relative to the hydrolyzable groups possessed by (a) hydrolyzable metal-containing compounds, it is preferably 0.2 times mole, more preferably 1 times mole, and further preferably 3 times mole. As the upper limit of the amount of the above-mentioned water, it is preferably 20 times mole, more preferably 15 times mole, and further preferably 10 times mole.

[0294] There are no particular limitations on the solvent used in the synthesis reaction of the metal compound (A). For example, the same solvent as that exemplified as the solvent (C) described below can be used. Typical solvents and solvent mixtures are those containing ester, ether or alcohol functional groups, such as a mixture of propylene glycol monomethyl ether acetate (PGMEA) and propylene glycol monomethyl ether (PGME) in a volume ratio of 70 / 30. Examples of other solvents that can be used include butanediol 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, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, propylene glycol monobutyl ether, 1-butanol, 2-butanol, 2-methyl-1-propanol, 4-methyl-1-propanol, 2-methyl-2-propanol, 2-methyl-3-propanol, 2-methyl-4-propanol, 2-methyl-5-propanol, 2-methyl-6-propanol, 2-methyl-7-propanol, 2-methyl-8-propanol, 2-methyl-9-propanol, 2-methyl-1-propanol, 2-methyl-2-propanol, 2-methyl-3-propanol, 2-methyl-3-propanol, 2-methyl-4-propanol, 2-methyl-1-propanol, 2-methyl-2-propanol, 2-methyl-3 ... propylene glycol dimethyl ether, diethylene glycol dimethyl ether, diamyl ether, isopentyl 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 monotert-butyl ether acetate, γ-butyrolactone, methyl isobutyl ketone, cyclopentyl methyl ether, etc.

[0295] <(B) Cross-linking agent>

[0296] The crosslinking agent (B) contained in the metal-containing film-forming composition of the present invention contains 2 or more and 4 or less cyclic ether structures having 2 to 13 carbon atoms in the molecule. It may also contain 3 of the above cyclic ether structures in the molecule. If the cyclic ether structures are contained in the molecule at less than 2 or more than 4, the stability of the metal compound in the composition is impaired, and a metal-containing film having excellent embedding properties cannot be formed.

[0297] Such a crosslinking agent does not impair the stability of the metal compound in the metal-containing film-forming composition, but reacts with the metal compound during baking to suppress the volume shrinkage of the metal compound, thereby forming a metal-containing film with excellent embedding properties.

[0298] The cyclic ether structure having 2 to 13 carbon atoms is preferably an epoxy group or an oxetanyl group.

[0299] Such a cyclic ether structure is preferred because it is excellent in reactivity with a metal compound and productivity.

[0300] As long as it is a cross-linking agent containing two or more epoxy groups or oxetane groups in the molecule, it can also be a compound, an oligomer or a polymer. In the case where the amount of carbon component in the metal-containing film is large, there is a risk of deteriorating the dry etching resistance, so it is more appropriate to use a monomolecular compound than a polymer. The weight average molecular weight Mw of the above polymer can be 1,000 to 10,000, and the weight average molecular weight Mw and the number average molecular weight Mn can be obtained as polystyrene standard conversion values ​​using tetrahydrofuran as a solvent by gel permeation chromatography (GPC).

[0301] The cross-linking agent (B) is preferably any one of the organic compounds represented by the following formula (1).

[0302] [Chemistry 29]

[0303]

[0304] (In the above formula (1), X is an m-valent organic group having 1 to 50 carbon atoms, L is a carbonyl group or a divalent organic group having 1 to 10 carbon atoms, R1 and R2 are each independently a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms, and R 1a is an alicyclic hydrocarbon group having 3 to 10 carbon atoms, l represents 0 or 1, and m represents 2 to 4.

[0305] In the above formula, R1 is more preferably a hydrogen atom, and R2 is more preferably any one of a hydrogen atom, a methyl group, and an ethyl group, and is further preferably an ethyl group.

[0306] In the above formula, R 1a It is an alicyclic hydrocarbon group having 3 to 10 carbon atoms, preferably a cycloalkyl group having 5 to 10 carbon atoms, more preferably a cyclopentyl group or a cyclohexyl group.

[0307] In the above formula, L is a carbonyl group or a divalent organic group having 1 to 10 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms, and further preferably a carbonyl group or a methylene group. L is 0 or 1, and more preferably 1.

[0308] In the above formula, X is an m-valent organic group having 1 to 50 carbon atoms, and is preferably one or more of a quaternary carbon atom, an aromatic ring, an alicyclic hydrocarbon, or a heterocyclic ring.

[0309] Such a cross-linking agent has excellent heat resistance, and therefore can react well with the metal compound during baking, thereby forming a metal-containing film with excellent embedding properties.

[0310] Preferred structures of X include the following.

[0311] [Chemistry 30]

[0312]

[0313] (In the above formula, n is 1 to 5, r is 0 or 1, s is 1 or 2, R3 and R4 are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms which may contain a halogen atom, R5 is a hydrogen atom, a hydroxyl group or an alkyl group having 1 to 10 carbon atoms, R6 and R7 are each independently a hydrogen atom, a hydroxyl group or an organic group having 1 to 10 carbon atoms which contains an alkyl group, an alkylene group or an alkynyl group, R8 is a hydrogen atom, a hydroxyl group or an organic group having 1 to 10 carbon atoms which contains an alkyl group, an alkylene group or an alkynyl group, and * represents a bond to L. The carbon atoms in the aromatic ring of the above formula may also have a hydroxyl group, a carboxyl group, a vinyl group, an ethynyl group, an amino group, a thioether group, or an alkyl group having 1 to 10 carbon atoms which may contain these groups as substituents.)

[0314] The above R3 and R4 are hydrogen atoms or alkyl groups having 1 to 10 carbon atoms which may contain halogen atoms, and are more preferably any of hydrogen atoms, methyl groups and CF3 groups.

[0315] The above R5 is a hydrogen atom, a hydroxyl group or an alkyl group having 1 to 10 carbon atoms, and is more preferably a hydrogen atom or a methyl group.

[0316] The above R6 and R7 are a hydrogen atom, a hydroxyl group, or an organic group containing an alkyl group, an alkylene group, or an alkynyl group having 1 to 10 carbon atoms, and are more preferably a hydrogen atom, a methyl group, or a hydroxyl group.

[0317] The above R8 is a hydrogen atom, a hydroxyl group, or an organic group containing an alkyl group, an alkylene group, or an alkynyl group having 1 to 10 carbon atoms, and is more preferably a hydrogen atom, a methyl group, or an allyl group.

[0318] The above n is 1 to 5, more preferably 1 to 3, and more preferably 1 from the viewpoint of dry etching resistance.

[0319] The above r is 0 or 1, and is more preferably 0 from the viewpoint of dry etching resistance.

[0320] If X is a crosslinking agent having the above structure, it is more preferable because it has excellent heat resistance and can react well with the metal compound during baking.

[0321] The amount of the cross-linking agent (B) added is preferably 5 to 100 parts by mass, more preferably 10 to 80 parts by mass, and further preferably 15 to 60 parts by mass, based on 100 parts by mass of the metal compound (A).

[0322] When the amount of the crosslinking agent (B) added is 5 parts by mass or more, the volume shrinkage of the metal compound can be suppressed, and a metal-containing film with excellent embedding properties can be formed. When the amount of the crosslinking agent added is 100 parts by mass or less, the amount of outgassing during baking can be suppressed, and a metal-containing film with a small number of defects can be formed.

[0323] <(C) Solvent>

[0324] The (C) solvent that can be used in the metal-containing film-forming composition of the present invention is not particularly limited as long as it can dissolve the (A) metal compound and (B) crosslinking agent, and (D) surfactant described later when contained, and other additives.

[0325] Specifically, for example, an organic solvent described in paragraphs

[0091] to

[0092] of Japanese Patent Application Laid-Open No. 2007-199653 may be added. More specifically, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, 2-heptanone, cyclopentanone, cyclohexanone, and γ-butyrolactone, or a mixture containing one or more of these may be preferably used.

[0326] (High boiling point solvent)

[0327] The metal-containing film-forming composition of the present invention may use the above-mentioned (C) solvent as a mixture of one or more organic solvents having a boiling point (value at 1 atmosphere (1013 hPa)) less than 180°C and one or more organic solvents having a boiling point of 180°C or more (high boiling point solvent).

[0328] As the high boiling point solvent, there is no particular limitation on hydrocarbons, alcohols, ketones, esters, ethers, chlorine-based solvents, etc., as long as they can dissolve the components of the metal-containing film-forming composition of the present invention. Specific examples thereof include 1-octanol, 2-ethylhexanol, 1-nonanol, 1-decanol, 1-undecanol, ethylene glycol, 1,2-propylene glycol, 1,3-butanediol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,5-hexanediol, 2,4-heptanediol, 2-ethyl-1,3-hexanediol, 1,2-propanediol ...1,2-propanediol, 1,3-butanediol, 1,2-propanediol, 1,3-butanediol, 1,2-propanediol, 1,3-butanediol, 1,3-butanediol, 1,3-butanediol, 1,3-butanediol, 1,3-butanediol, 1,3-butanediol, 1,3-butanediol, 1,3-butanediol, 1,3-butanediol, 1,3-butanediol, 1,3-butanediol, 1,3-butanediol, 1,3-butanediol, 1,3-butanediol, 1,3-butanediol, 1,3-butanediol, 1,3-butanedi diol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, glycerol, 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 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 diacetic acid Ester, dipropylene glycol methyl n-propyl ether, dipropylene glycol methyl ether acetate, 1,4-butanediol diacetate, 1,3-butanediol diacetate, 1,6-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, etc., which can be used alone or in combination.

[0329] The high boiling point solvent is combined with the temperature at which the metal-containing film-forming composition of the present invention is heat-treated, and can be appropriately selected from, for example, the above. The boiling point of the high boiling point solvent is preferably 180°C to 300°C, and more preferably 200°C to 300°C. If it is such a boiling point, there is no risk of volatilization too fast during baking (heat treatment), so the defects caused by drying during film formation can be suppressed. In addition, if it is such a boiling point, there is no risk of remaining in the film without volatilization after baking, so there is no risk of adverse effects on the film properties such as etching resistance.

[0330] The amount of the solvent (C) to be added is preferably in the range of 200 to 10,000 parts by mass, more preferably 250 to 5,000 parts by mass, based on 100 parts by mass of the metal compound (A).

[0331] In addition, the blending amount of the above-mentioned high boiling point solvent is preferably 1 to 30 parts by mass relative to 100 parts by mass of the organic solvent having a boiling point of less than 180° C. Such a blending amount is preferred because it can provide sufficient thermal fluidity during baking and will not remain in the film to cause deterioration of film properties such as etching resistance.

[0332] <Other ingredients>

[0333] The above-mentioned metal-containing film-forming composition, when it is a metal-containing film-forming composition that can be used as a resist underlayer film used in a multilayer resist method, can contain one or more of the above-mentioned (A) metal compound, (B) cross-linking agent, and (C) solvent, and may also contain at least one of (D) surfactant, (E) thermal acid generator, (F) photoacid generator, and (G) other cross-linking agents as needed.

[0334] Hereinafter, components that may be contained in the metal-containing film-forming composition of the present invention other than the above-mentioned (A) metal compound, (B) cross-linking agent, and (C) solvent will be described.

[0335] [(D) Surfactant]

[0336] In the metal-containing film-forming composition of the present invention, in order to improve the coating property in spin coating, a (D) surfactant may be added. The surfactant may be used alone or in combination of two or more. As the surfactant, for example, those described in paragraphs

[0142] to

[0147] in Japanese Patent Publication No. 2009-269953 may be used. The amount of the surfactant added is preferably 0.001 to 20 parts by mass, more preferably 0.01 to 10 parts by mass, relative to 100 parts by mass of the above-mentioned (A) metal compound. If it is within such a range, the coating property can be improved reliably, and a thin and uniform close-contact film can be formed.

[0337] [(E) Thermal acid generator]

[0338] The metal-containing film-forming composition of the present invention may further contain (E) a thermal acid generator in order to promote a crosslinking reaction by heat.

[0339] Examples of the thermal acid generator (E) that can be used in the metal-containing film-forming composition of the present invention include the following general formula (7) and the like.

[0340] [Chemistry 31]

[0341]

[0342] (Where X A - Represents a non-nucleophilic counter ion. 70 , R71 , R 72 , and R 73 Each represents a hydrogen atom or a linear, branched, or cyclic alkyl, alkenyl, oxoalkyl, or oxoalkenyl group having 1 to 12 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or an aryloxoalkyl group, and a part or all of the hydrogen atoms of these groups may be substituted by an alkoxy group or the like. 70 and R 71 , or R 70 , R 71 and R 72 It can also form a ring. In the case of forming a ring, R 70 and R 71 , or R 70 , R 71 and R 72 represents an alkylene group having 3 to 10 carbon atoms, or a heteroaromatic ring having a nitrogen atom in the ring.

[0343] The above R 70 , R 71 , R 72 , and R 73 They may be the same as or different from each other. Specifically, examples of the alkyl group include methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norbornyl and adamantyl.

[0344] Examples of the alkenyl group include vinyl, allyl, propenyl, butenyl, hexenyl, and cyclohexenyl.

[0345] Examples of the oxoalkyl group include 2-oxocyclopentyl, 2-oxocyclohexyl, 2-oxopropyl, 2-cyclopentyl-2-oxoethyl, 2-cyclohexyl-2-oxoethyl, and 2-(4-methylcyclohexyl)-2-oxoethyl.

[0346] Examples of the oxoalkenyl group include 2-oxo-4-cyclohexenyl and 2-oxo-4-propenyl.

[0347] Examples of the aryl group include phenyl, naphthyl, and the like; or alkoxyphenyl groups such as p-methoxyphenyl, m-methoxyphenyl, o-methoxyphenyl, ethoxyphenyl, p-tert-butoxyphenyl, and m-tert-butoxyphenyl; alkylphenyl groups such as 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, ethylphenyl, 4-tert-butylphenyl, and 4-butylphenyl; alkylnaphthyl groups such as methylnaphthyl and ethylnaphthyl; alkoxynaphthyl groups such as methoxynaphthyl and ethoxynaphthyl; dialkylnaphthyl groups such as dimethylnaphthyl and diethylnaphthyl; and dialkoxynaphthyl groups such as dimethoxynaphthyl and diethoxynaphthyl.

[0348] Examples of the aralkyl group include benzyl, phenylethyl, and phenethyl.

[0349] Examples of the aryloxyalkyl group include 2-aryl-2-oxoethyl groups such as 2-phenyl-2-oxoethyl, 2-(1-naphthyl)-2-oxoethyl and 2-(2-naphthyl)-2-oxoethyl.

[0350] In addition, in R 70 and R 71 , or R 70 , R 71 and R 72 In the case of a heteroaromatic ring having a nitrogen atom in the forming formula, examples thereof include imidazole derivatives (e.g., imidazole, 4-methylimidazole, 4-methyl-2-phenylimidazole, etc.), pyrazole derivatives, furazolone derivatives, pyrroline derivatives (e.g., pyrroline, 2-methyl-1-pyrroline, etc.), pyrrolidine derivatives (e.g., pyrrolidine, N-methylpyrrolidine, pyrrolidone, N-methylpyrrolidone, etc.), imidazoline derivatives, imidazolidinyl derivatives, pyridine derivatives (e.g., pyridine, picoline, ethylpyridine, propylpyridine, butylpyridine, 4-(1-butylpentyl)pyridine, dimethylpyridine, trimethylpyridine, triethylpyridine, phenylpyridine, 3-methyl-2-phenylpyridine, 4-tert-butylpyridine, diphenylpyridine, benzylpyridine, methoxypyridine, butoxypyridine, dimethoxypyridine, 1-methyl-2-pyridone, 4-pyrrolidinylpyridine, 1-methyl-4-phenylpyridine, 2-(1-ethylpropyl)pyridine, aminopyridine, dimethylaminopyridine, etc.), pyridazine derivatives, pyrimidine derivatives, pyrazine derivatives, pyrazoline derivatives, pyrazolidine derivatives, piperidine derivatives, piperazine derivatives, morpholine derivatives, indole derivatives, isoindole derivatives, 1H-indazole derivatives, indoleline derivatives, quinoline derivatives (e.g., quinoline, 3-quinolinecarbonitrile, etc.), isoquinoline derivatives, phenanthroline derivatives, quinazoline derivatives, quinoxaline derivatives, phthalazine derivatives, purine derivatives, pteridine derivatives, carbazole derivatives, phenanthridine derivatives, acridine derivatives, phenazine derivatives, 1,10-phenanthroline derivatives, adenine derivatives, adenosine derivatives, guanine derivatives, guanosine derivatives, uracil derivatives, uridine derivatives, etc.

[0351] As mentioned above, as X A -Examples of the non-nucleophilic counter ions include halide ions such as chloride ion and bromide ion, fluoroalkylsulfonate ions such as trifluoromethanesulfonate ion, 1,1,1-trifluoroethanesulfonate ion and nonafluorobutanesulfonate ion, arylsulfonate ions such as toluenesulfonate ion, benzenesulfonate ion, 4-fluorobenzenesulfonate ion and 1,2,3,4,5-pentafluorobenzenesulfonate ion, alkylsulfonate ions such as methanesulfonate ion and butanesulfonate ion, Examples of the present invention include imidic acid ions such as bis(trifluoromethylsulfonyl)imide ion, bis(perfluoroethylsulfonyl)imide ion, and bis(perfluorobutylsulfonyl)imide ion; methylated acid ions such as tris(trifluoromethylsulfonyl)methide ion and tris(perfluoroethylsulfonyl)methide ion; and further examples thereof include sulfonate ions substituted with fluorine at the α-position as represented by the following general formula (8); and sulfonate ions substituted with fluorine at the α- and β-positions as represented by the following general formula (9).

[0352] [Chemistry 32]

[0353]

[0354] In the above general formula (8), R 81 is a hydrogen atom, a linear, branched, or cyclic alkyl group having 1 to 23 carbon atoms, an acyl group, an alkenyl group having 2 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aryloxy group. 91 It is a hydrogen atom, a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms.

[0355] Specific examples of the thermal acid generator include the following, but the thermal acid generator is not limited to these.

[0356] [Chemistry 33]

[0357]

[0358] The (E) thermal acid generator contained in the metal-containing forming composition of the present invention can be used alone or in combination of two or more. The amount of the thermal acid generator added is preferably 0.05 to 30 parts by mass, more preferably 0.1 to 10 parts by mass, relative to 100 parts by mass of the above-mentioned (A) metal compound. If it is 0.05 parts by mass or more, the acid generation amount or the cross-linking reaction is sufficient, and if it is 30 parts by mass or less, there is less risk of mixing caused by the migration of the acid to the upper layer resist.

[0359] The metal-containing film-forming composition of the present invention preferably does not contain a thermal acid generator from the viewpoint of improving the embedding property of the uneven substrate. The acid generator promotes the self-condensation of the metal compound, thereby hindering the reaction with the crosslinking agent and deteriorating the embedding property.

[0360] [(F) Photoacid generator]

[0361] In the metal-containing film-forming composition of the present invention, in order to appropriately adjust the pattern shape, exposure sensitivity, etc. of the resist upper film, (F) a photoacid generator may be added. The photoacid generator may be used alone or in combination of two or more. As for the photoacid generator, for example, those described in paragraphs

[0160] to

[0179] in Japanese Patent Gazette No. 2009-126940 may be used. The amount of the photoacid generator added is preferably 0.05 to 30 parts by mass, and more preferably 0.1 to 10 parts by mass, relative to 100 parts by mass of the above-mentioned (A) metal compound. As long as the amount of the photoacid generator added is within the above range, the resolution is good, and there will be no problem of foreign matter generated after the resist is developed or peeled off.

[0362] [(G) Other cross-linking agents]

[0363] In addition, in the metal-containing film-forming composition of the present invention, in addition to the above-mentioned (B) cross-linking agent, in order to further improve the hardening property and suppress the intermixing with the upper film of the resist, (G) other cross-linking agents may also be added. As a cross-linking agent, there is no particular limitation, and cross-linking agents of various known systems can be widely used. As an example, melamine-based cross-linking agents, glycoluril-based cross-linking agents, benzoguanamine-based cross-linking agents, urea-based cross-linking agents, β-hydroxyalkylamide-based cross-linking agents, isocyanurate-based cross-linking agents, aziridine-based cross-linking agents, oxazoline-based cross-linking agents, and phenol-based cross-linking agents can be exemplified. The above-mentioned (G) other cross-linking agents can be used alone or in combination of two or more, and the amount added in the case of adding a cross-linking agent is preferably 5 to 50 parts by mass, and more preferably 10 to 40 parts by mass, relative to 100 parts by mass of the above-mentioned (A) metal compound. If the addition amount is 5 parts by mass or more, sufficient hardening property is exhibited, and intermixing with the upper film of the resist can be suppressed. On the other hand, when the added amount is 50 parts by mass or less, there is no concern that the dry etching resistance will deteriorate due to a decrease in the ratio of the (A) metal compound in the composition.

[0364] [Plasticizer]

[0365] In addition, a plasticizer may be added to the metal-containing film-forming composition of the present invention. As a plasticizer, there is no particular limitation, and plasticizers of various known systems can be widely used. As an example, low molecular weight compounds such as phthalates, adipic acid esters, phosphates, trimellitic acid esters, and citrates, polyethers, polyesters, and polymers such as polyacetal polymers recorded in Japanese Patent Publication No. 2013-253227 can be exemplified. The amount of the added plasticizer is preferably 1% to 500% by mass relative to 100 parts by mass of the above-mentioned (A) metal compound. If the amount added is in such a range, the pattern is excellent in filling and homogenization.

[0366] <Method for Forming Metal-Containing Film>

[0367] The present invention uses the metal-containing film-forming composition to form a filling film that functions as a resist underlayer film of a multilayer resist film used for photolithography or a planarizing film for semiconductor manufacturing.

[0368] The method for forming a resist lower film or a filling film using the metal-containing film-forming composition of the present invention is to apply the above-mentioned metal-containing film-forming composition to the processed substrate by spin coating or the like. By using the spin coating method or the like, good filling characteristics can be obtained. In order to prevent the solvent from evaporating and mixing with the resist upper film or the resist intermediate film after spin coating, baking (heat treatment) is performed to promote the crosslinking reaction. The baking is preferably carried out in the range of 100°C to 600°C for 10 to 600 seconds, and more preferably in the range of 200°C to 500°C for 10 to 300 seconds. If the influence on equipment damage or wafer deformation is taken into consideration, the upper limit of the heating temperature in the wafer process of photolithography is preferably below 600°C, and more preferably below 500°C.

[0369] In addition, the above-mentioned film formation method using the metal-containing film-forming composition of the present invention is to apply the metal-containing film-forming composition of the present invention on the processed substrate by the same spin coating method as mentioned above, and calcine the above-mentioned metal-containing film-forming composition in an environment with an oxygen concentration of not less than 0.1 volume % and not more than 21 volume % to harden it, thereby also forming the metal-containing film as a resist underlayer film.

[0370] By calcining the metal-containing film-forming composition of the present invention in such an oxygen environment, a fully hardened film can be obtained. It is also fine to be in the air as the environment during baking. It is more ideal to seal in inert gases such as N2, Ar, and 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, which is preferably less than 1,000ppm, and more preferably less than 100ppm (volume basis). If the oxidation of the metal-containing film during baking is prevented, it is more ideal that there will be no increase in absorption or reduction in etching resistance.

[0371] If the above method is used, an amorphous metal-containing film can be formed, so it is more ideal. Considering the dry etching resistance, the metal-containing film is preferably amorphous. If it is amorphous, it is not easy to produce ion scattering, so it is easy to perform vertical dry etching, and there is no risk of crystal grains deteriorating the roughness of the pattern.

[0372] <Pattern Formation Method Using Metal-Containing Film-Forming Composition>

[0373] The present invention also provides a pattern forming method using the metal-containing film-forming composition. Hereinafter, an example of a pattern forming method using a multilayer resist process using the metal-containing film-forming composition of the present invention is given for explanation, but the present invention is not limited to the following aspects. In addition, in the following multilayer resist process, the resist upper film, the resist intermediate film, and the resist lower film are arranged in this order from a distance relative to the processed substrate.

[0374] The present invention provides a pattern forming method as a pattern forming method of a two-layer resist process using the above-mentioned metal-containing film-forming composition, which is a method for forming a pattern on a processed substrate, comprising the following steps:

[0375] (I-1) After applying the metal-containing film-forming composition on a substrate to be processed, heat treatment is performed to form a metal-containing film.

[0376] (I-2) forming a resist upper layer film on the metal-containing film using a photoresist material,

[0377] (I-3) after exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0378] (I-4) using the patterned resist upper layer film as a mask, transferring the pattern to the metal-containing film by dry etching, and

[0379] (I-5) Using the patterned metal-containing film as a mask, the substrate to be processed is processed to form a pattern on the substrate to be processed.

[0380] Since the resist upper layer film in the above two-layer resist process exhibits etching resistance to chlorine-based gas, it is more ideal to use an etching gas mainly composed of chlorine-based gas to perform dry etching of the metal-containing film using the resist upper layer film as a mask in the above two-layer resist process.

[0381] In addition, the present invention provides a pattern forming method as a pattern forming method of a three-layer resist process using the above-mentioned metal-containing film-forming composition, which is a method for forming a pattern on a processed substrate, comprising the following steps:

[0382] (II-1) forming a resist underlayer film on a substrate to be processed,

[0383] (II-2) coating the metal-containing film-forming composition on the resist underlayer film and then performing a heat treatment to form a metal-containing film;

[0384] (II-3) forming a resist upper layer film on the metal-containing film using a photoresist material,

[0385] (II-4) After exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0386] (II-5) using the patterned resist upper layer film as a mask, transferring the pattern to the metal-containing film by dry etching,

[0387] (II-6) using the metal-containing film having the transferred pattern as a mask, transferring the pattern to the resist underlayer film by dry etching,

[0388] (II-7) The substrate to be processed is processed using the patterned resist underlayer film as a mask to form a pattern on the substrate to be processed.

[0389] The resist upper film of the above three-layer resist process exhibits etching resistance due to chlorine-based gases, so in the above three-layer resist process, it is more ideal to use an etching gas containing chlorine-based gases as the main component to dry-etch the metal-containing film using the resist upper film as a mask. Then, the metal-containing film exhibits etching resistance due to oxygen-based gases, so it is more ideal to use an etching gas containing oxygen-based gases as the main component to dry-etch the resist lower film using the metal-containing film as a mask. In the case where an organic lower film is used as the resist lower film, since it exhibits etching resistance due to fluorine-based gases, it is more ideal to use an etching gas containing fluorine-based gases as the main component to dry-etch the substrate to be processed using the organic lower film as a mask.

[0390] In such a multi-layer resist process, the present invention can use the above-mentioned metal-containing film-forming composition as a resist underlayer film to directly form a metal-containing film on the processed substrate, or can form a metal-containing film separately after the resist underlayer film is formed on the processed substrate.

[0391] In addition, the present invention provides a pattern forming method as a pattern forming method of a three-layer resist process using such a metal-containing film-forming composition, which is a method for forming a pattern on a processed substrate, comprising the following steps:

[0392] (III-1) After applying the metal-containing film-forming composition on a substrate to be processed, heat treatment is performed to form a metal-containing film.

[0393] (III-2) forming a silicon-containing resist intermediate film on the metal-containing film,

[0394] (III-3) forming a resist upper layer film on the silicon-containing resist intermediate film using a photoresist material,

[0395] (III-4) after exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0396] (III-5) using the patterned resist upper layer film as a mask, transferring the pattern to the silicon-containing resist intermediate film by dry etching,

[0397] (III-6) using the transferred patterned silicon-containing resist intermediate film as a mask, transferring the pattern to the metal-containing film by dry etching, and

[0398] (III-7) The substrate to be processed is processed using the patterned metal-containing film as a mask to form a pattern on the substrate to be processed.

[0399] use Figure 1 The present invention provides the following pattern forming method as a pattern forming method for a three-layer resist process using such a metal-containing film-forming composition: Figure 1 In the method (A), the metal-containing film-forming composition is used to form a metal-containing film 3 on a workpiece layer 2 on a workpiece substrate 1, a silicon-containing resist intermediate film 4 is formed on the metal-containing film, and a photoresist material is used to form a resist upper film 5 on the silicon-containing resist intermediate film. Then, as Figure 1 As in (B), the exposed portion 6 of the resist upper film is pattern exposed. Figure 1 (C), by developing with a developer, a resist upper film pattern 5a is formed on the resist upper film, such as Figure 1 (D) is the same as that of the embodiment of the present invention, wherein the patterned resist upper film is used as a mask, and the silicon-containing resist intermediate film pattern 4a is transferred to the above-mentioned silicon-containing resist intermediate film by dry etching, such as Figure 1 (E), the silicon-containing resist intermediate film to which the above pattern is transferred is used as a mask, and the metal-containing film pattern 3a is transferred to the above metal-containing film by dry etching, such as Figure 1 Generally, the pattern 2 a is formed on the substrate 1 by processing the layer on the substrate 1 using the patterned metal-containing film as a mask.

[0400] The silicon-containing resist intermediate film in the above three-layer resist process exhibits etching resistance to chlorine-based gases, so in the above three-layer resist process, it is more ideal to use an etching gas mainly composed of chlorine-based gases to dry-etch the metal-containing film using the silicon-containing resist intermediate film as a mask.

[0401] As the silicon-containing resist intermediate film of the above-mentioned three-layer resist process, a polysiloxane-based intermediate film is also suitable. By giving the silicon-containing resist intermediate film an antireflection effect, reflection can be suppressed. In particular, for 193nm exposure, if a material with high etching selectivity with a substrate containing a large number of aromatic groups is used as an organic film, the k value becomes high and the substrate reflection becomes high, but by giving the silicon-containing resist intermediate film an absorption that has an appropriate k value, reflection can be suppressed and the substrate reflection can be made less than 0.5%. As a silicon-containing resist intermediate film with an antireflection effect, it is suitable to use a polysiloxane with a pendant anthracene group for 248nm and 157nm exposure, a pendant phenyl group for 193nm exposure, or a light-absorbing group with a silicon-silicon bond, and cross-linked with acid or heat.

[0402] Furthermore, the present invention can also be used as a pattern forming method of a four-layer resist process further including a step of forming an organic thin film.

[0403] As a pattern forming method of a four-layer resist process using such a metal-containing film-forming composition, the present invention may be a method for forming a pattern on a processed substrate, characterized by comprising the following steps:

[0404] After applying the metal-containing film-forming composition described above on a substrate to be processed, a step of forming a metal-containing film by heat treatment is performed,

[0405] forming a silicon-containing resist intermediate film on the resist underlayer film,

[0406] The step of forming an organic thin film on the silicon-containing resist intermediate film,

[0407] On the organic film, a step of forming a resist upper film using a photoresist material,

[0408] After exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0409] The step of using the patterned resist upper film as a mask to transfer the pattern to the organic thin film and the silicon-containing resist intermediate film by dry etching,

[0410] The step of transferring the pattern to the metal-containing film by dry etching using the silicon-containing resist intermediate film to which the pattern has been transferred as a mask, and

[0411] The process further comprises the step of processing the substrate to be processed by using the patterned metal-containing film as a mask to form a pattern on the substrate to be processed.

[0412] The organic thin film is not particularly limited, and is preferably a functional film having a desired function in a multilayer resist process, for example, an organic antireflection film (BARC) or an adhesion film.

[0413] A pattern forming method of a four-layer resist process further including a step of forming an organic anti-reflective film (BARC) or a close contact film as the organic thin film is, for example, a pattern forming method having the following steps:

[0414] On a substrate to be processed, a metal-containing film is formed using the metal-containing film-forming composition.

[0415] On the metal-containing film, a silicon-containing resist intermediate film is formed using a silicon-containing resist intermediate film material.

[0416] On the silicon-containing resist intermediate film, an organic anti-reflection film (BARC) or a close contact film is formed as an organic thin film.

[0417] On the BARC or the adhesion film, a photoresist material is used to form a resist upper film.

[0418] After the resist upper layer film is pattern-exposed, it is developed by a developer to form a pattern on the resist upper layer film.

[0419] The patterned resist upper layer film is used as a mask to transfer the pattern to the BARC or the adhesion film and the silicon-containing resist intermediate film by dry etching.

[0420] The pattern is transferred to the metal-containing film by dry etching using the silicon-containing resist intermediate film having the transferred pattern as a mask.

[0421] The step of processing the substrate to be processed by using the patterned metal-containing film as a mask to form a pattern on the substrate to be processed.

[0422] In addition, an inorganic hard mask interlayer may be formed instead of the silicon-containing resist interlayer. In this case, a semiconductor device circuit pattern may be formed on the substrate by at least the following steps:

[0423] Using the metal-containing film-forming composition of the present invention to form a metal-containing film on a substrate to be processed,

[0424] An inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxide nitride film is formed on the metal-containing film.

[0425] A photoresist composition is used to form a resist upper film on the inorganic hard mask intermediate film, and a circuit pattern is formed on the resist upper film.

[0426] The pattern is transferred to the inorganic hard mask intermediate film using the patterned resist upper layer film as a mask.

[0427] The pattern is transferred to the metal-containing film using the patterned inorganic hard mask intermediate film as a mask.

[0428] Furthermore, the substrate to be processed is processed using the patterned metal-containing film as a mask to form a pattern on the substrate to be processed.

[0429] The present invention provides a pattern forming method as a pattern forming method including the step of forming an inorganic hard mask intermediate film, which is a method for forming a pattern on a processed substrate, comprising the following steps:

[0430] (IV-1) After applying the metal-containing film-forming composition on a substrate to be processed, heat treatment is performed to form a metal-containing film.

[0431] (IV-2) forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxide nitride film on the metal-containing film,

[0432] (IV-3) forming an organic thin film on the inorganic hard mask intermediate film,

[0433] (IV-4) forming a resist upper layer film on the organic thin film using a photoresist material,

[0434] (IV-5) After exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0435] (IV-6) using the patterned resist upper film as a mask, transferring the pattern to the organic thin film and the inorganic hard mask intermediate film by dry etching,

[0436] (IV-7) using the inorganic hard mask intermediate film to which the pattern has been transferred as a mask, transferring the pattern to the metal-containing film by dry etching, and

[0437] (IV-8) The substrate to be processed is processed using the patterned metal-containing film as a mask to form a pattern on the substrate to be processed.

[0438] As described above, when an inorganic hard mask intermediate film is formed on a metal-containing film, a silicon oxide film, a silicon nitride film, and a silicon oxide nitride film (SiON film) can be formed by a CVD method, an ALD method, or the like. For example, a method for forming a silicon nitride film is described in Japanese Patent Application Publication No. 2002-334869 and International Publication No. 2004 / 066377. The film thickness of the inorganic hard mask intermediate film is preferably 5 to 200 nm, more preferably 10 to 100 nm. In addition, as an inorganic hard mask intermediate film, a SiON film having a high effect as an anti-reflection film is most preferably used. The substrate temperature when forming the SiON film is 300 to 500°C, so as a metal-containing film, it is sufficient if it can withstand a temperature of 300 to 500°C. The metal-containing film-forming composition used in the present invention has high heat resistance and can withstand high temperatures of 300°C to 500°C, and thus may be a combination of an inorganic hard mask intermediate film formed by CVD or ALD and a metal-containing film formed by spin coating.

[0439] A photoresist film may be directly formed on the inorganic hard mask interlayer as a resist upper film, or an organic thin film such as an organic antireflection film (BARC) or a close contact film may be formed on the inorganic hard mask interlayer by spin coating as described above, and a photoresist film may be formed thereon. In particular, when a SiON film is used as the inorganic hard mask interlayer, the two-layer antireflection film of the SiON film and the BARC makes it possible to suppress reflection even in immersion exposure with a high NA exceeding 1.0. Another benefit of forming the BARC is that the tailing of the photoresist pattern directly on the SiON film is reduced.

[0440] In the above-mentioned pattern forming method, the resist upper layer film may be either positive or negative, and the same photoresist composition as commonly used may be used. In addition, the photoresist composition may also contain metal atoms such as Sn, In, Ga, Ge, Al, Ce, La, Cs, Zr, Hf, Ti, Bi, Sb, Zn, etc. When the resist upper layer film is formed by the above-mentioned photoresist composition, it may be formed by a spin coating method or by a vapor deposition process such as CVD or ALD.

[0441] In the case of forming the photoresist upper film by spin coating, pre-baking is performed after the resist is applied, preferably in the range of 10 to 300 seconds at 60 to 180° C. Thereafter, exposure, post-exposure baking (PEB), and development are performed according to the usual method to obtain a resist pattern. In addition, the thickness of the resist upper film is not particularly limited, but is preferably 10 to 500 nm, and particularly preferably 20 to 400 nm.

[0442] In the case of forming the resist upper layer film by vapor deposition treatment by CVD or ALD, the photoresist composition is a EUV-sensitive metal oxide-containing film, and the metal is selected from Sn, Zr, Hf, Ti, Bi, Sb, etc., among which Sn is preferably excellent in EUV sensitivity. The metal oxide-containing film may also be a photosensitive organic metal oxide film of an organic tin oxide (e.g., halogenated alkyl Sn, alkoxyalkyl Sn, or amide alkyl Sn). A plurality of specific examples of suitable precursors include trimethyltin chloride, dimethyltin dichloride, methyltin trichloride, tris(dimethylamino)methyltin(IV), and (dimethylamino)trimethyltin(IV).

[0443] The metal oxide-containing film can be deposited by PECVD or PEALD using a Lam Vector (registered trademark) tool, for example, and the Sn oxide precursor is separated from the O precursor / plasma in the ALD embodiment. The evaporation temperature is preferably in the range of 50°C to 600°C. The evaporation pressure is preferably between 100 and 6,000 mTorr. The flow rate of the precursor liquid of the metal oxide-containing film (such as an organic tin oxide precursor) can be 0.01 to 10 cmm, and the gas flow rate (CO2, CO, Ar, N2) can also be 100 to 10,000 sccm. The plasma power uses high-frequency plasma (such as 13.56 MHz, 27.1 MHz, or higher frequencies), and can be 200 to 1,000 W per 300 mm wafer station. The evaporation thickness is preferably 100 to 2,000 angstroms.

[0444] Examples of the exposure light include high energy rays having a wavelength of 300 nm or less, and specific examples thereof include excimer lasers of 248 nm, 193 nm, and 157 nm, and soft X-rays, electron beams, and X-rays of 3 to 20 nm.

[0445] As a method for forming a pattern of the resist upper layer film, optical lithography with a wavelength of 5 nm to 300 nm, direct writing with an electron beam, nanoimprinting, or a combination thereof is preferably used.

[0446] In addition, the development method in the above-mentioned pattern forming method is preferably alkali development or development using an organic solvent.

[0447] Then, the obtained resist pattern is used as a mask for etching. The etching of the silicon-containing resist intermediate film or the inorganic hard mask intermediate film in the three-layer resist process is performed by using a fluorochlorocarbon-based gas and the resist upper film pattern as a mask. Thereby, a silicon-containing resist intermediate film pattern or an inorganic hard mask intermediate film pattern is formed.

[0448] Then, the obtained silicon-containing resist interlayer film pattern or inorganic hard mask interlayer film pattern is used as a mask to perform etching processing of the metal-containing film. The etching processing of the metal-containing film is preferably performed using an etching gas mainly containing chlorine-based gas.

[0449] The subsequent etching of the processed substrate can also be performed by a conventional method. For example, if the processed substrate is a SiO2, SiN, or silicon dioxide-based low-k dielectric film, etching is performed using a chlorofluorocarbon-based gas as the main component. When the substrate is processed and etched using a chlorofluorocarbon-based gas, the silicon-containing resist intermediate film pattern in the three-layer resist process is stripped off at the same time as the substrate is processed.

[0450] The metal-containing film obtained by using the metal-containing film-forming composition of the present invention has a characteristic of being excellent in etching resistance when etching these substrates to be processed.

[0451] In addition, there is no particular limitation on the object to be processed (substrate to be processed), and substrates such as Si, α-Si, p-Si, SiO2, SiN, SiON, W, TiN, Al, etc., or a substrate on which a layer to be processed is formed, etc. can be used. As the layer to be processed, various Low-k films such as Si, SiO2, SiON, SiN, p-Si, α-Si, W, W-Si, Al, Cu, Al-Si, and their stopper films are used, and a thickness of 50 to 10,000 nm, particularly 100 to 5,000 nm, can be formed. In addition, when forming a layer to be processed, the substrate and the layer to be processed can be made of different materials.

[0452] The pattern forming method using the metal-containing film-forming composition of the present invention preferably uses a substrate to be processed with a structure or height difference of more than 30nm. As mentioned above, the metal-containing film-forming composition of the present invention has excellent filling / planarization characteristics, so even if the substrate to be processed has a structure or height difference (concave and convex) of more than 30nm in height, a flat metal-containing film can be formed. The height of the structure or height difference of the above-mentioned processed substrate is preferably more than 30nm, more preferably more than 50nm, and further preferably more than 100nm. In the method for processing the above-mentioned substrate with a height pattern, the metal-containing film-forming composition of the present invention is formed into a film and filled / planarized, thereby making the film thickness of the silicon-containing resist intermediate film and the resist upper film formed later uniform, so it becomes easy to ensure the exposure depth margin (DOF) during optical lithography, which is very ideal.

[0453] Furthermore, the present invention may further include a step of forming an organic lower layer film using an organic lower layer film material. A pattern forming method using a multilayer resist process using such a metal-containing film-forming composition is provided, comprising the following steps:

[0454] On a substrate to be processed, a metal-containing film is formed using the metal-containing film-forming composition.

[0455] On the metal-containing film, an organic lower layer film is formed using an organic lower layer film material.

[0456] On the organic lower layer film, a silicon-containing resist intermediate film is formed using a silicon-containing resist intermediate film material, and an organic anti-reflective film (BARC) or a close contact film is formed on the silicon-containing resist intermediate film according to the needs.

[0457] A photoresist material is used to form a resist upper film on the silicon-containing resist intermediate film, the BARC, or the adhesive film.

[0458] After the resist upper layer film is pattern-exposed, it is developed by a developer to form a pattern on the resist upper layer film.

[0459] The pattern is transferred to the BARC or the adhesion film and the silicon-containing resist intermediate film by dry etching using the patterned resist upper layer film as a mask.

[0460] The pattern is transferred to the organic lower layer film by dry etching using the silicon-containing resist intermediate film as a mask.

[0461] The organic lower layer film is used as a mask to transfer the pattern to the metal-containing film.

[0462] The process further comprises the step of processing the substrate to be processed by using the patterned metal-containing film as a mask to form a pattern on the substrate to be processed.

[0463] As the organic underlayer film material that can be used for the above-mentioned organic underlayer film, in addition to the 4,4'-(9-fluorenylene)bisphenol novolac resin (molecular weight 11,000) described in Japanese Patent Publication No. 2005-128509, which is known as an underlayer film for a three-layer resist method or a two-layer resist method using a silicon resist composition, many resins including novolac resins, which are known as resist underlayer film materials for a two-layer resist method or a three-layer resist method, can be used. In addition, in the case where it is desired to increase the heat resistance to a higher level than that of a conventional novolac, a polycyclic skeleton such as a 6,6'-(9-fluorenylene)-di(2-naphthol) novolac resin can be added, and a polyimide resin (for example, Japanese Patent Publication No. 2004-153125) can also be selected.

[0464] The organic lower film can be formed on the metal-containing film by spin coating or the like using a composition solution, similarly to the photoresist composition. After the organic lower film is formed by spin coating or the like, it is desirable to perform baking to evaporate the organic solvent. The baking temperature is in the range of 80 to 400° C., and the baking time is preferably in the range of 10 to 300 seconds.

[0465] An organic hard mask formed by a CVD method or an ALD method may be used instead of the organic underlayer film.

[0466] The organic underlayer film in the multilayer resist process exhibits etching resistance to chlorine-based gas, so in the multilayer resist process, dry etching of the metal-containing film using the organic underlayer film as a mask is preferably performed using an etching gas mainly containing chlorine-based gas.

[0467] In addition, the present invention provides a pattern forming method as a pattern forming method for another multilayer resist process using such a metal-containing film-forming composition, which is a method for forming a pattern on a processed substrate, comprising the following steps:

[0468] (V-1) After applying the metal-containing film-forming composition on a substrate to be processed, heat treatment is performed to form a metal-containing film.

[0469] (V-2) forming an organic intermediate film on the metal-containing film,

[0470] (V-3) forming a silicon-containing resist interlayer film, or a combination of an inorganic hard mask interlayer film selected from silicon oxide film, silicon nitride film, and silicon oxide nitride film and an organic thin film on the organic interlayer film,

[0471] (V-4) forming a resist upper film on the silicon-containing resist intermediate film or the organic film using a photoresist material,

[0472] (V-5) After exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0473] (V-6) using the patterned resist upper film as a mask, transferring the pattern to the silicon-containing resist intermediate film, or the organic thin film and the inorganic hard mask intermediate film by dry etching,

[0474] (V-7) using the transferred pattern of the silicon-containing resist interlayer or the inorganic hard mask interlayer as a mask, and transferring the pattern to the organic interlayer by dry etching.

[0475] (V-8) using the organic intermediate film as a mask, transferring a pattern to the metal-containing film by dry etching, and

[0476] (V-9) The substrate to be processed is processed using the patterned metal-containing film as a mask to form a pattern on the substrate to be processed.

[0477] According to the pattern forming method of the multilayer resist process using the metal-containing film-forming composition of the present invention, a fine pattern can be formed on a workpiece with high precision.

[0478] <Tonal Reversal Pattern Formation Method Using Metal-Containing Film-Forming Composition>

[0479] In addition, the present invention provides a tone-reversal pattern forming method using such a metal-containing film-forming composition, which is a method for forming a pattern on a processed substrate, comprising the following steps:

[0480] (VI-1) forming a resist underlayer film on a substrate to be processed,

[0481] (VI-2) forming a silicon-containing resist intermediate film, or a combination of an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxide nitride film and an organic thin film on the resist underlayer film,

[0482] (VI-3) forming a resist upper film using a photoresist material on the silicon-containing resist intermediate film or the combination of the inorganic hard mask intermediate film and the organic thin film,

[0483] (VI-4) After exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0484] (VI-5) using the patterned resist upper film as a mask, transferring the pattern to the silicon-containing resist intermediate film, or the organic thin film and the inorganic hard mask intermediate film by dry etching,

[0485] (VI-6) using the transferred patterned silicon-containing resist interlayer film or inorganic hard mask interlayer film as a mask, transferring the pattern to the resist underlayer film by dry etching,

[0486] (VI-7) coating the metal-containing film-forming composition on the patterned resist underlayer film, and then performing a heat treatment to coat the metal-containing film, thereby filling the space between the resist underlayer film patterns with the metal-containing film.

[0487] (VI-8) etching back the metal-containing film covering the patterned resist underlayer film by chemical stripper or dry etching to expose the top surface of the patterned resist underlayer film;

[0488] (VI-9) removing the silicon-containing resist interlayer film or the inorganic hard mask interlayer film remaining on the top surface of the resist underlayer film by dry etching,

[0489] (VI-10) removing the patterned resist underlayer film whose surface is exposed by dry etching to form a reverse pattern of the original pattern on the metal-containing film,

[0490] (VI-11) The metal-containing film having the reverse pattern formed therein is used as a mask to process the substrate to form a reverse pattern on the substrate.

[0491] use Figure 2 The present invention provides a tone-reversal pattern forming method using a metal-containing film-forming composition, as a tone-reversal pattern forming method using such a metal-containing film-forming composition, comprising the following steps: Figure 2 (G) is generally used to form a resist lower layer film 7 made of a coating type organic lower layer film material on a processed layer 2 on a processed substrate 1, and on the resist lower layer film 7, a silicon-containing resist intermediate film 4 or a combination of an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxide nitride film and an organic thin film is formed, and on the silicon-containing resist intermediate film 4 or the combination of an inorganic hard mask intermediate film and an organic thin film, a resist upper layer film 5 is formed using a photoresist material. Then, as Figure 2 As in (H), the exposed portion 6 of the resist upper film is pattern exposed. Figure 2 As in (I), by developing with a developer, a resist upper film pattern 5a is formed on the resist upper film. Figure 2 (J) is generally the case, using the patterned resist upper film as a mask, and transferring the silicon-containing resist intermediate film pattern 4a or the inorganic hard mask intermediate film pattern to the silicon-containing resist intermediate film 4, or the organic thin film and the inorganic hard mask intermediate film by dry etching, such as Figure 2 (K), the silicon-containing resist intermediate film or inorganic hard mask intermediate film with the transferred pattern is used as a mask, and the resist lower film pattern 7a is transferred to the resist lower film by dry etching, such as Figure 2 In the above-mentioned patterned resist underlayer film, the metal-containing film 8 is covered with the metal-containing film-forming composition, and the space between the resist underlayer film patterns 7a is filled with the metal-containing film 8, as shown in FIG. Figure 2Generally, the metal-containing film 8 covered on the patterned resist lower film is etched back by chemical stripping or dry etching to form a metal-containing film pattern 8a in which the resist lower film pattern is reversed, and the top surface of the patterned resist lower film is exposed, as shown in FIG. Figure 2 The silicon-containing resist intermediate film or inorganic hard mask intermediate film remaining on the top surface of the resist lower film pattern 7a is removed by dry etching, as shown in FIG. Figure 2 (O), the above-mentioned resist lower layer film with the exposed surface formed with the pattern is removed by dry etching to form a reverse pattern of the original pattern on the metal-containing film, such as Figure 2 Generally, the reverse pattern 2a is formed on the processed layer by processing the processed layer using the metal-containing film on which the reverse pattern is formed as a mask.

[0492] As described above, when a resist underlayer film is formed on a substrate to be processed, the resist underlayer film can be formed by a method using a coating type resist underlayer film material, or a CVD method, an ALD method, etc. As for the coating type resist underlayer film material, examples thereof include Japanese Patent Publication No. 2012-001687, Japanese Patent Publication No. 2012-077295, Japanese Patent Publication No. 2004-264710, Japanese Patent Publication No. 2005-043471, Japanese Patent Publication No. 2005-250434, Japanese Patent Publication No. 2007-293294, etc. Japanese Patent Application Publication No. 2008-065303, Japanese Patent Application Publication No. 2004-205685, Japanese Patent Application Publication No. 2007-171895, Japanese Patent Application Publication No. 2009-014816, Japanese Patent Application Publication No. 2007-199653, Japanese Patent Application Publication No. 2008-274250, Japanese Patent Application Publication No. 2010-12265 6, Japanese Patent Publication No. 2012-214720, Japanese Patent Publication No. 2014-029435, International Publication No. 2012 / 077640, International Publication No. 2010 / 147155, International Publication No. 2012 / 176767, Japanese Patent Publication No. 2005-128509, Japanese Patent Publication No. 2006-259249, Japanese Patent Publication No. 2006-259482, Japanese Patent Publication No. 2006-293298, Japanese Patent Publication No. 2007-316282, Japanese Patent Publication No. 2012-145897, Japanese Patent Publication No. 2017-119671, Japanese Patent Publication No. 2019-044022, etc. The resins and compositions disclosed in the publication are as follows:

[0493] In the tone reversal pattern forming method, after the obtained resist underlayer film pattern is coated with a metal-containing film-forming composition, it is preferable to remove the metal-containing film using a dry etching gas mainly composed of a chlorine-based gas to expose the top surface of the resist underlayer film pattern. Thereafter, the silicon-containing resist intermediate film or the inorganic hard mask intermediate film remaining on the resist underlayer film is removed by dry etching using a chlorofluorocarbon-based gas, and the exposed resist underlayer film pattern on the surface is removed by dry etching using an oxygen-based gas, thereby forming a metal-containing film pattern.

[0494] In the above tone reversal pattern forming method, the resist lower film pattern preferably has a structure or height difference of more than 30nm. As mentioned above, the metal-containing film forming composition of the present invention has excellent filling / planarization properties, so even if the processed film has a structure or height difference (concave and convex) of more than 30nm in height, a flat metal-containing film can be formed. The height of the structure or height difference of the above resist lower film pattern is preferably more than 30nm, more preferably more than 50nm, and further preferably more than 100nm. In the method of reversing the resist lower film pattern having the above-mentioned height pattern, the metal-containing film forming composition of the present invention is formed into a film and then filled / planarized, thereby enabling the pattern to be reversed / transferred with high precision, which is very ideal. Compared with the resist underlayer film using the conventional coating type resist underlayer film material, the resist underlayer film has excellent resistance to dry etching using chlorofluorocarbon gas, so by reversing the resist underlayer film pattern with the above-mentioned metal-containing film forming composition, the desired resist pattern can be formed on the processed film with high precision.

[0495] Example

[0496] Hereinafter, the present invention will be described in more detail with reference to synthesis examples, comparative synthesis examples, examples, and comparative examples, but the present invention is not limited thereto.

[0497] [Synthesis example]

[0498] In the following synthesis examples, the following organic group raw material group G: (G1) to (G11) and silicon-containing organic group raw material group H: (H1) to (H2) were used.

[0499] Organic group raw material group G: (G1) to (G11) are shown below.

[0500] [Chemistry 34]

[0501]

[0502] The silicon-containing organic group raw material group H: (H1) to (H2) are shown below.

[0503] [Chemistry 35]

[0504]

[0505] As the metal source M, the following metal compounds were used.

[0506] (M1): Titanium tetraisopropoxide (Sigma-Aldrich Corp, 377996)

[0507] (M2): Zr(OnBu)4: zirconium(IV)tetrabutoxide (80% by mass in 1-butanol solution) (Tokyo Chemical Industry Co., Ltd., Z0016)

[0508] (M3): Hf(OnBu)4: Hafnium(IV) n-butoxide (Sigma-Aldrich Corp, 667943)

[0509] [Synthesis Example 1] Synthesis of Metal-Containing Film-Forming Compound (A-1)

[0510] Under a nitrogen environment, 40.5 g of a n-butanol solution of 28.4 g of titanium tetraisopropoxide (M1) was stirred while 54.5 g of a n-butanol solution of 1.6 g of deionized water was added dropwise at room temperature for 2 hours. 11.2 g of an organic group raw material group (G1) was added to the obtained solution, and stirred at room temperature for 30 minutes. The solution was concentrated at 30°C under reduced pressure, and then further heated to 60°C, and continued to be heated under reduced pressure until no distillate was produced. When no distillate was observed, 69.0 g of a PGMEA / PGME (mass ratio 70 / 30) solution was added, and heated at 40°C under reduced pressure until IPA was no longer distilled, to obtain a PGMEA / PGME solution of a metal-containing film-forming compound (A-1). The concentration of components other than the solvent in the above solution is 17% by mass.

[0511] [Synthesis of Compounds (A-2) to (A-11)]

[0512] Except that the metal source M and the compound group G were used in the amounts shown in Table 1, the same reaction conditions as those in Synthesis Example 1 were followed to obtain compounds (A-2) to (A-11) shown in Table 1.

[0513] [Table 1]

[0514]

[0515] [Synthesis Example 2] Synthesis of Metal-Containing Film-Forming Compound (A-12)

[0516] Under a nitrogen environment, 12.6 g of titanium tetraisopropoxide (M1) was dissolved in 23.4 g of PGMEA / PGME (mass ratio 70 / 30) solution, the reaction temperature was raised to 50°C while stirring, and 6.5 g of compound H1 was added dropwise to the above solution. After the addition, the reaction temperature was set to 60°C and stirring was continued for 2 hours. Then, a mixture in which 5.4 g of compound G4 was suspended in 10.8 g of PGMEA / PGME (mass ratio 70 / 30) solution was added to the above reaction system, and stirring was continued at a reaction temperature of 60°C for 1 hour. After cooling to room temperature, the obtained reaction solution was filtered with a 0.45 μm PTFE filter to obtain a PGMEA / PGME solution of a metal-containing film-forming compound (A-12). The concentration of components other than the solvent in the above solution is 15% by mass.

[0517] [Synthesis of Compounds (A-12) to (A-15)]

[0518] Compounds (A-12) to (A-15) shown in Table 2 were obtained under the same reaction conditions as in Synthesis Example 2 except that the metal source M, compound group G and compound group H were used in the amounts shown in Table 2.

[0519] [Table 2]

[0520]

[0521] [Crosslinking agents B-1 to B-14)]

[0522] The crosslinking agents (B-1) to (B-14) used in the metal-containing film-forming composition are shown below.

[0523] B-6, 7, 13 used the following.

[0524] B-6: ETERNACOLL (registered trademark) OXIPA manufactured by UBE Co., Ltd.

[0525] B-7: OXT-121 manufactured by Toa Gosei Co., Ltd.

[0526] B-13: ETERNACOLL (registered trademark) OXBP manufactured by UBE Co., Ltd.

[0527] [Chemistry 36]

[0528]

[0529] [Comparative Example Cross-linking Agent (R-1 to R-6)]

[0530] The comparative example crosslinking agents (R-1) to (R-6) used in the metal-containing film-forming composition for comparative example are shown below: For R-2, OXT-212 manufactured by Toagosei Co., Ltd. was used.

[0531] [Chemistry 37]

[0532]

[0533] [Preparation of Metal-Containing Film-Forming Composition (MUL-1)]

[0534] The metal-containing film-forming compound (A-1) was dissolved in a mixed solvent of propylene glycol monomethyl ether acetate (PGMEA) and propylene glycol monomethyl ether (PGME) at the ratio shown in Table 3, and filtered through a 0.02 μm membrane filter to prepare a metal-containing film-forming composition (MUL-1).

[0535] [Preparation of Metal-Containing Film-Forming Compositions (MUL-2 to 17) and Comparative Examples of Metal-Containing Film-Forming Compositions (Comparative Examples MUL-1 to 10)]

[0536] Each liquid was prepared in the same manner as MUL-1 except that the types and contents of each component were as shown in Table 3. In Table 3, "-" indicates that the component was not used. Ethylene glycol dibenzyl ether: boiling point 364°C was used as the high boiling point solvent (D-1), and the following formula (E-1) was used as the acid generator (TAG).

[0537] [Chemistry 38]

[0538]

[0539] [Table 3]

[0540]

[0541] [Evaluation of film thickness uniformity]

[0542] The resist underlayer film forming composition prepared as described above (MUL-1 to 17, comparative examples MUL-1 to 9) was coated on a 300 mm silicon substrate and calcined at 350°C for 60 seconds. The film thickness was measured at 225 points from the center to the outer edge of the 300 mm wafer. The case where the difference between the maximum film thickness and the minimum film thickness was less than 3% relative to the average film thickness (b) was judged as A (extremely good), the case where it was more than 3% and less than 5% was judged as B (good), and the case where it was more than 5% was judged as C (poor).

[0543] Comparative Example 1-9 was discontinued because precipitates were generated after the sample preparation. Compound (R-6) was used as the crosslinking agent (B). It is presumed that the compound (R-6) contained a large amount of hydroxyl groups and thus reacted with the metal compound to generate precipitates.

[0544] [Table 4]

[0545]

[0546] The metal-containing film-forming composition of the present invention (Examples 1-1 to 1-17) can obtain good results in film thickness uniformity. It is speculated that this is because the (A) metal compound and the (B) cross-linking agent react well. In particular, the composition using the (B) cross-linking agent having a ring structure exhibits extremely good film thickness uniformity. On the other hand, the film thickness uniformity of Comparative Examples 1-1 to 1-3 formed only by metal-containing film-forming compounds after high-temperature baking is not sufficient. In addition, Comparative Example 1-4 is a comparative example in which the cross-linking agent R-1 is a polymer having a cyclic ether structure in the repeating unit, and has high reactivity, so the proportion of self-cross-linking becomes high. It is speculated that the reaction with the metal compound becomes insufficient and the heat resistance becomes poor. Comparative Example 1-5, it is speculated that the cross-linking agent R-2 used in the comparative example is monofunctional and has insufficient heat resistance, so the film thickness uniformity cannot be improved. Comparison Examples 1-6 and 1-7 using multifunctional cross-linking agents (R-3 and R-4) and Comparison Example 1-8 using a cross-linking agent (R-5) having excellent heat resistance, tentatively show an improvement in film thickness uniformity compared to Comparison Example 1-1 composed solely of metal compounds.

[0547] [Landfill characteristics evaluation]

[0548] The above-prepared compositions (MUL-1~17, and comparative examples MUL-1~8) were each coated on three types of SiO2 wafer substrates with dense line and space patterns (substrate A), heated at 350°C for 60 seconds using a hot plate to form a metal-containing film with a thickness of 80nm.

[0549] Pattern A: Line width 60nm, line depth 120nm, distance between the centers of two adjacent lines 120nm Pattern B: Line width 50nm, line depth 120nm, distance between the centers of two adjacent lines 100nm Pattern C: Line width 40nm, line depth 120nm, distance between the centers of two adjacent lines 80nm

[0550] The substrate A used is a substrate having Figure 3The base substrate 9 (SiO2 wafer substrate) with a dense line and space pattern as shown in (Q) (top view) and (R) (cross-sectional view) of FIG. The cross-sectional shape of each wafer substrate obtained by the embedding evaluation was observed using an electron microscope (S-4700) manufactured by Hitachi, Ltd. to confirm whether there was a gap (void) at the bottom of the metal-containing film filled between the lines. The results are shown in Table 5.

[0551] In the case of using a metal-containing film-forming composition having good embedding properties, in this evaluation, Figure 3 As shown in (S), there is a metal-containing film 10 that fills the lines of the base substrate 9 having a dense line and space pattern and has no gaps at the bottom of the metal-containing film. In the case of using a metal-containing film-forming composition with poor filling characteristics, such as Figure 3 As shown in (T), a gap 11 is generated at the bottom of the metal-containing film filling the gaps between the lines.

[0552] It is preferable that the pattern A can be embedded, it is more preferable that the pattern B having a finer pattern can be embedded, and it is further preferable that the pattern C having a still finer pattern can be embedded.

[0553] [Table 5]

[0554]

[0555] As shown in Table 5, Examples 2-1 to 2-17 using the metal-containing film-forming composition (MUL-1 to 17) of the present invention can confirm that in pattern A, no gaps are generated at the bottom of the pattern even after baking at 350°C, and dense line and spacing patterns can be filled, and good filling characteristics are maintained even under high-temperature baking conditions.

[0556] In particular, Examples 2-4 to 2-11 using metal compounds having ligands containing crosslinking groups (A-4 to A-11) showed excellent embedding properties even in finer patterns B and C. It is speculated that this is because the metal compound has ligands containing crosslinking group structures, which improves the heat resistance of the metal compound and further improves the reactivity with the crosslinking agent (B). Examples using metal compounds whose hydrolyzable groups are substituted with silicon-containing groups (A-12 to A-15) did not have sufficient embedding properties in the finer pattern C. It is speculated that this is because those having alkoxy groups as hydrolyzable groups further promote the reaction with the crosslinking agent (B).

[0557] In addition, the metal-containing film-forming composition (MUL-3) in which the crosslinking agent (B) contains an aromatic ring structure exhibits superior embedding properties in pattern B compared to the metal-containing film-forming compositions (MUL-1 and 2) in which the crosslinking agent (B) does not contain an aromatic ring structure. This is presumably because the crosslinking agent (B) contains an aromatic ring structure, which improves the heat resistance of the crosslinking agent and further improves the reactivity with the metal compound (A).

[0558] In MUL-17, gaps were observed in pattern C. It is presumed that the acid generator promoted the self-condensation of the metal compound (A) and reduced the reactivity with the cross-linking agent (B). Therefore, in the fine substrate (pattern C) that is more susceptible to heat from the substrate, the volume of the metal compound shrank more and gaps were generated.

[0559] Since Comparative Example MUL-2 does not contain the crosslinking agent (B) but contains the metal compound (A-7) having a ligand having a crosslinking group structure, it is presumed that the heat resistance of the metal compound is improved, and the pattern A can be filled without gaps. On the other hand, the Comparative Examples MUL-1 and MUL-3, which do not contain the crosslinking agent (B) and are composed of metal compounds having no ligand having a crosslinking structure, have gaps observed in all patterns.

[0560] Unlike the metal-containing film-forming composition of the present invention, in Comparative Examples 2-4 to 2-8, in which the (B) crosslinking agent does not contain two or more cyclic ether structures having 2 to 13 carbon atoms in the molecule (Comparative Examples MUL-4 to MUL-8), gaps were observed at the bottom of the finer patterns B and C after baking at 350°C. This is presumably because the reactivity between the (A) metal compound and the (B) crosslinking agent is poor, and the heat resistance of the metal-containing film is insufficient, so the volume shrinkage caused by high-temperature baking is large, resulting in gaps.

[0561] [Evaluation of etching resistance]

[0562] The metal-containing film-forming composition (MUL-1 to 17, and comparative examples MUL-1 to 8, 10) was applied on a silicon substrate and heated at 350°C for 60 seconds using a hot plate to form a metal-containing film with a thickness of 80 nm, and the film thickness a was measured. Then, each etching was performed under the following conditions (condition 1 and condition 2) using an etching device TE8500 manufactured by Tokyo Electron, and the film thickness b was measured. The film thickness etched in 1 minute was calculated from the film thickness etched during the specified time (film thickness b-film thickness a) as the etching rate (nm / min).

[0563] Under condition 1, an etching rate of 50 nm / min or less was judged as A (extremely good), a rate of more than 50 nm / min and less than 70 nm / min was judged as B (good), and a rate of more than 70 nm / min was judged as C (poor).

[0564] Under condition 2, an etching rate of 50 nm / min or less was judged as A (extremely good), a rate of more than 50 nm / min and less than 70 nm / min was judged as B (good), and a rate of more than 70 nm / min was judged as C (poor).

[0565] The results are shown in Table 6.

[0566] Dry etching conditions 1

[0567] Pressure: 200mT

[0568] RF power: 300W

[0569] CF4 gas flow rate: 100sccm

[0570] Time: 20 seconds

[0571] Dry etching conditions 2

[0572] Pressure: 500mT

[0573] RF power: 100W

[0574] O2 gas flow rate: 30sccm

[0575] N2 gas flow rate: 270sccm

[0576] Time: 20 seconds

[0577] [Table 6]

[0578]

[0579] As shown in Table 6, Examples 3-1 to 3-17 using the metal-containing film-forming composition (MUL-1 to 17) of the present invention each exhibited excellent dry etching resistance to fluorine gas and oxygen. In particular, it was found that the metal-containing film-forming composition containing a metal compound having a multidentate ligand exhibited extremely excellent dry etching resistance.

[0580] In Comparative Example MUL-4, it is presumed that the amount of carbon contained in the metal-containing film increased, possibly because the polymer (R-1) was used as the cross-linking agent (B), and thus the dry etching resistance was poor.

[0581] Comparative Example 3-9 evaluated a resin (R-5) that can be used as an organic underlayer film, but the result was that the dry etching resistance of the metal-containing film was insufficient.

[0582] [Pattern Formation Method]

[0583] The above-mentioned metal-containing film-forming composition (MUL-1 to 17) was coated on a SiO2 wafer substrate having a groove pattern (groove width 10 μm, groove depth 0.10 μm), and calcined at 350°C for 60 seconds in the atmosphere to form a metal-containing film with a thickness of 80 nm. An organic lower film material (SOC-1) was coated thereon, and baked at 350°C for 60 seconds to form an organic lower film with a thickness of 150 nm. A silicon-containing resist intermediate film material (SOG-1) was coated thereon and baked at 220°C for 60 seconds to form a silicon-containing resist intermediate film (hereinafter also referred to as resist intermediate film) with a thickness of 30 nm. A single-layer resist for ArF of a resist upper film material was coated thereon, and baked at 105°C for 60 seconds to form a photoresist film with a thickness of 100 nm. A wet protection film material (TC-1) was applied on the photoresist film and baked at 90° C. for 60 seconds to form a protection film with a film thickness of 50 nm.

[0584] As a coating type organic lower film material (SOC-1), a polymer represented by an organic lower film polymer (SOP1) and an organic solvent containing 0.1 mass % of FC-4430 (manufactured by Sumitomo 3M Co., Ltd.) are dissolved in the proportions shown in Table 7, and filtered through a fluororesin filter with a pore size of 0.2 μm to prepare a coating type anti-etching agent lower film material (SOC-1).

[0585] [Table 7]

[0586]

[0587] Table 8 shows the structural formula of the organic underlayer membrane polymer (SOP1) used.

[0588] [Table 8]

[0589]

[0590] As a silicon-containing anti-etching intermediate film material (SOG-1), a polymer represented by ArF silicon-containing intermediate film polymer (SiP1) and a thermal cross-linking catalyst (CAT1) are dissolved in an organic solvent containing 0.1% by mass of FC-4430 (produced by Sumitomo 3M Co., Ltd.) in the proportions shown in Table 9, and filtered through a fluororesin filter with a pore size of 0.1 μm to prepare a silicon-containing anti-etching intermediate film material (SOG-1).

[0591] [Table 9]

[0592]

[0593] The structural formulas of the ArF silicon-containing interlayer polymer (SiP1) and the thermal crosslinking catalyst (CAT1) are shown below.

[0594] [Chemistry 39]

[0595]

[0596] As an anti-etching agent upper layer film material (single-layer anti-etching agent for ArF), a polymer (RP1), an acid generator (PAG1), and a basic compound (Amine1) are dissolved in a solvent containing 0.1% by mass of a surfactant FC-4430 (manufactured by Sumitomo 3M Co., Ltd.) at a ratio as shown in Table 10, and the mixture is filtered through a 0.1 μm fluororesin filter to prepare the material.

[0597] [Table 10]

[0598]

[0599] The polymer (RP1), the acid generator (PAG1), and the basic compound (Amine1) used in the resist upper layer film material (ArF single-layer resist) are shown below.

[0600] [Chemistry 40]

[0601]

[0602] As a wet protective film material (TC-1), the protective film polymer (PP1) was dissolved in an organic solvent at a ratio in Table 11, and filtered through a 0.1 μm fluororesin filter to prepare the wet protective film material (TC-1).

[0603] [Table 11]

[0604]

[0605] The protective film polymer (PP1) used in the wet protective film material (TC-1) is shown below.

[0606] [Chemistry 41]

[0607]

[0608] Then, it was exposed by using an ArF immersion exposure device (manufactured by Nikon Corporation; NSR-S610C, NA1.30, σ0.98 / 0.65, 35 degree dipole s-polarized illumination, 6% half-step phase shift mask), baked at 100°C for 60 seconds (PEB), and developed with a 2.38 mass % tetramethylammonium hydroxide (TMAH) aqueous solution for 30 seconds to obtain a 60nm1:1 positive line and space pattern (resist upper film pattern).

[0609] Then, the resist intermediate film was etched by dry etching using the resist upper film pattern as a mask to form a resist intermediate film pattern, the organic lower film was etched using the obtained resist intermediate film pattern as a mask to form an organic lower film pattern, the metal-containing film was etched using the obtained organic lower film pattern as a mask to form a metal-containing film pattern, and the SiO2 film was etched using the obtained metal-containing film pattern as a mask. Etching was performed using an etching device CE-300I manufactured by ULVAC under the following conditions.

[0610] Transfer conditions of the resist upper layer film pattern to the resist intermediate film.

[0611] Dry etching conditions in CF4 gas

[0612] Pressure: 1Pa

[0613] Antenna RF power: 100W

[0614] Bias RF power: 15W

[0615] CF4 gas flow rate: 15sccm

[0616] Time: 60 seconds

[0617] Transfer conditions of the resist interlayer film pattern to the organic underlayer film.

[0618] Dry etching conditions in O2 gas

[0619] Pressure: 1Pa

[0620] Antenna RF power: 300W

[0621] Bias RF power: 0W

[0622] O2 gas flow rate: 25sccm

[0623] Time: 40 seconds

[0624] Transfer conditions of organic underlayer film pattern to metal-containing film.

[0625] Dry etching conditions in Cl2 gas

[0626] Pressure: 1Pa

[0627] Antenna RF power: 320W

[0628] Bias RF power: 30W

[0629] Cl2 gas flow rate: 25sccm

[0630] Time: 45 seconds

[0631] Transfer conditions of metal-containing film patterns to SiO2 films.

[0632] Dry etching conditions in CF4 gas

[0633] Pressure: 1Pa

[0634] Antenna RF power: 100W

[0635] Bias RF power: 15W

[0636] CF4 gas flow rate: 15sccm

[0637] Time: 60 seconds

[0638] Table 12 shows the results of observing the pattern cross section using an electron microscope (S-4700) manufactured by Hitachi, Ltd.

[0639] [Table 12]

[0640]

[0641]

[0642] As shown in Table 12, in Examples 4-1 to 4-17 using the metal-containing film-forming composition (MUL-1 to 17) of the present invention, the upper film pattern of the resist can be well transferred to the substrate in any case, confirming that the metal-containing film-forming composition of the present invention is suitable for use in micro-processing by the multilayer resist method.

[0643] [SOC pattern inversion method]

[0644] A coating type resist lower film material (SOC-1) as a resist lower film was applied on a silicon wafer substrate formed with a SiO2 film, and baked at 350°C for 60 seconds to form a resist lower film with a film thickness of 120nm. A silicon-containing resist intermediate film material (SOG-1) was applied thereon and baked at 220°C for 60 seconds to form a resist intermediate film with a film thickness of 30nm. A single layer resist for ArF as a resist upper film material was applied thereon and baked at 105°C for 60 seconds to form a photoresist film with a film thickness of 100nm. A wet protection film material (TC-1) was applied on the photoresist film and baked at 90°C for 60 seconds to form a protection film with a film thickness of 50nm.

[0645] The organic lower film material (SOC-1), the silicon-containing resist intermediate film material (SOG-1), the resist upper film material (single-layer resist for ArF), and the wetting protective film material (TC-1) on the photoresist film used the same materials as the above-mentioned pattern forming method (Example 4).

[0646] Then, it was exposed by an ArF immersion exposure device (manufactured by Nikon Corporation; NSR-S610C, NA1.30, σ0.98 / 0.65, 35 degree dipole s-polarized illumination, 6% half-step phase shift mask), baked at 100°C for 60 seconds (PEB), and developed by 2.38 mass % tetramethylammonium hydroxide (TMAH) aqueous solution for 30 seconds to obtain a 60nm1:1 positive line and space pattern (resist upper film pattern).

[0647] Then, the resist intermediate film was etched by dry etching using the resist upper film pattern as a mask using a Tokyo Electron etching apparatus Telius to form a hard mask pattern, and the resist lower film (SOC-1) was etched using the obtained hard mask pattern as a mask to form a SOC-1 film pattern. The etching conditions were as follows.

[0648] Transfer conditions of the resist upper layer film pattern to the resist intermediate film.

[0649] Chamber pressure: 50mT

[0650] RF power (upper): 500W

[0651] RF power (lower): 300W

[0652] CF4 gas flow rate: 150sccm

[0653] CHF3 gas flow rate: 50sccm

[0654] Time: 20 seconds

[0655] Transfer conditions of the hard mask pattern to the resist underlayer film.

[0656] Chamber pressure: 10mT

[0657] RF power (upper): 1,000W

[0658] RF power (lower): 300W

[0659] CO2 gas flow rate: 150sccm

[0660] CO gas flow rate: 50sccm

[0661] N2 gas flow rate: 50sccm

[0662] H2 gas flow rate: 150sccm

[0663] Time: 100 seconds

[0664] Then, the above-mentioned metal-containing film-forming composition (MUL-1~17, Comparative Examples MUL-1, 4~6) is applied on the obtained SOC-1 film pattern, and calcined at 350°C for 60 seconds in the atmosphere to form a metal-containing film with a film thickness of 80nm. After that, the metal-containing film covering the SOC-1 film pattern is etched to expose the top surface of the SOC-1 film pattern. The resist intermediate film remaining on the surface of the SOC-1 film pattern exposed on the top surface is removed by etching, and then the exposed SOC-1 film pattern is removed by etching, and the above-mentioned pattern is reversed on the metal-containing film, and the obtained metal-containing film pattern is used as a mask to etch the SiO2 film. As a comparative example, the SiO2 film is also etched without using the metal-containing film-forming composition and using the SOC-1 film pattern as a mask (Comparative Example 5-5). The etching conditions are as follows.

[0665] Etch-back of metal-containing film (exposure of SOC-1 film pattern) conditions.

[0666] Pressure: 1Pa

[0667] Antenna RF power: 320W

[0668] Bias RF power: 30W

[0669] Cl2 gas flow rate: 25sccm

[0670] Time: 20 seconds

[0671] Removal of the resist intermediate film remaining on the SOC-1 film pattern.

[0672] Dry etching conditions in CF4 gas

[0673] Pressure: 1Pa

[0674] Antenna RF power: 100W

[0675] Bias RF power: 15W

[0676] CF4 gas flow rate: 15sccm

[0677] Time: 45 seconds

[0678] Removal of SOC-1 film pattern.

[0679] Dry etching conditions in O2 gas

[0680] Pressure: 1Pa

[0681] Antenna RF power: 300W

[0682] Bias RF power: 0W

[0683] O2 gas flow rate: 25sccm

[0684] Time: 35 seconds

[0685] Transfer conditions of metal-containing film patterns to SiO2 films.

[0686] Dry etching conditions in CF4 gas

[0687] Pressure: 1Pa

[0688] Antenna RF power: 100W

[0689] Bias RF power: 15W

[0690] CF4 gas flow rate: 15sccm

[0691] Time: 60 seconds

[0692] Comparative Example 5-9: Transfer conditions of SOC-1 film pattern to SiO2 film.

[0693] Dry etching conditions in CF4 gas

[0694] Pressure: 1Pa

[0695] Antenna RF power: 100W

[0696] Bias RF power: 15W

[0697] CF4 gas flow rate: 15sccm

[0698] Time: 60 seconds

[0699] Table 13 shows the results of observing the pattern cross section using an electron microscope (S-4700) manufactured by Hitachi, Ltd.

[0700] [Table 13]

[0701]

[0702] As shown in Table 13, in Examples 5-1 to 5-17 using the metal-containing film-forming composition (MUL-1 to 17) of the present invention, the SOC-1 film pattern was reversed with good accuracy in all cases, and the reversed pattern without pattern collapse was finally well transferred to the substrate. Based on this situation, it was confirmed that the metal-containing film-forming composition of the present invention is suitable for use in micro-processing using a tone reversal etching method in a multilayer resist process. On the other hand, in Comparative Example 5-5 in which the SOC-1 film pattern was directly transferred to the SiO2 film, the etching resistance of the SOC-1 film was not sufficient, so wrinkles in the pattern shape were confirmed. In addition, in Comparative Examples 5-1 to 4, which were confirmed to have insufficient performance in the evaluation of the filling characteristics (pattern A), the metal-containing film could not be filled to the bottom between the SOC-1 film patterns, so the pattern could not be reversed, and finally a good reversed pattern could not be obtained.

[0703] Based on the above, if it is the metal-containing film-forming composition of the present invention, it has both high-level filling / planarization characteristics and dry etching resistance, so it is extremely useful as a resist underlayer film material used in a multilayer resist method and a reversal agent used in a tone reversal etching method. In addition, it can be seen that if it is the pattern forming method of the present invention using it, even if the processed body is a substrate with a height difference, a fine pattern can still be formed with high precision.

[0704] This manual contains the following aspects.

[0705] [1]: A metal-containing film-forming composition comprising:

[0706] (A) a metal compound containing at least one metal selected from the group consisting of Ti, Zr, and Hf,

[0707] (B) a cross-linking agent containing 2 to 13 carbon cyclic ether structures in the molecule, and

[0708] (C) Solvent.

[0709] [2]: The metal-containing film-forming composition according to [1], wherein the (B) cross-linking agent has two or more epoxy groups or oxetanyl groups in the molecule.

[0710] [3]: The metal-containing film-forming composition according to [1] or [2], wherein the cross-linking agent (B) is any one of the organic compounds represented by the following formula (1);

[0711] [Chemistry 42]

[0712]

[0713] In the above formula (1), X is an m-valent organic group having 1 to 50 carbon atoms, L is a carbonyl group or a divalent organic group having 1 to 10 carbon atoms, R1 and R2 are each independently a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms, and R 1a It is an alicyclic hydrocarbon group having 3 to 10 carbon atoms, l represents 0 or 1, and m represents 2 to 4.

[0714] [4]: The metal-containing film-forming composition according to [3], wherein X in the formula (1) is an m-valent organic group containing one or more of a quaternary carbon atom, an aromatic ring, an alicyclic hydrocarbon, or a heterocyclic ring.

[0715] [5]: The metal-containing film-forming composition according to [3] or [4], wherein X in the formula (1) is any one of the following structures;

[0716] [Chemistry 43]

[0717]

[0718] In the above formula, n is 1 to 5, r is 0 or 1, s is 1 or 2, R3 and R4 are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms which may also contain a halogen atom, R5 is a hydrogen atom, a hydroxyl group or an alkyl group having 1 to 10 carbon atoms, R6 and R7 are each independently a hydrogen atom, a hydroxyl group or an organic group having 1 to 10 carbon atoms which contains an alkyl group, an alkylene group or an alkynyl group, R8 is a hydrogen atom, a hydroxyl group or an organic group having 1 to 10 carbon atoms which contains an alkyl group, an alkylene group or an alkynyl group, * represents a bonding portion with L, and the carbon atoms in the aromatic ring of the above formula may also have a hydroxyl group, a carboxyl group, a vinyl group, an ethynyl group, an amino group, a thioether group, or an alkyl group having 1 to 10 carbon atoms which may also contain these groups as substituents.

[0719] [6]: The metal-containing film-forming composition according to any one of [1] to [5], wherein the (A) metal compound is a metal compound represented by the following formula (2);

[0720] [Chemistry 44]

[0721] Ln a MX b (2)

[0722] In the formula, M is any one of Ti, Zr, and Hf; Ln is independently a monodentate ligand or a polydentate ligand having 1 to 30 carbon atoms; Xn is independently selected from a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, -NR a R b The hydrolyzable group R a and Rb Each is independently a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; a+b=4, and a and b are integers of 0-4.

[0723] [7]: The metal-containing film-forming composition according to [6], wherein the formula (2) is a structure of the following formula (3);

[0724] [Chemistry 45]

[0725] M(OR 1A )4 (3)

[0726] Wherein, M is Ti, Zr, or Hf, R 1A It is a monovalent organic group having 1 to 20 carbon atoms.

[0727] [8]: A metal-containing film-forming composition as described in [6] or [7], wherein the metal compound (A) is a reaction product of a compound derived from the metal compound represented by the formula (2) and an organic compound having 1 to 30 carbon atoms and containing at least one crosslinking group represented by the following general formulae (a-1) to (a-4), (b-1) to (b-4), (c-1) to (c-3) and (d-1) to (d-2);

[0728] [Chemistry 46]

[0729]

[0730] In the general formulas (a-1) to (a-4), R a are independently a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, q represents 0 or 1, and * represents a bonding portion;

[0731] [Chemistry 47]

[0732]

[0733] In this general formula, R b are independently a hydrogen atom or a methyl group, and may be the same or different in the same formula, R c is hydrogen, or a substituted or unsubstituted saturated or unsaturated monovalent organic group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted aralkyl group having 7 to 31 carbon atoms, and * represents a bonding part;

[0734] [Chemistry 48]

[0735]

[0736] In the general formulae (c-1) to (c-3), Y1 is independently a divalent organic group having 1 to 20 carbon atoms, R is a hydrogen atom, a substituted or unsubstituted saturated or unsaturated monovalent organic group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted aralkyl group having 7 to 31 carbon atoms, and R d are independently an organic group represented by the following general formula (c-4) in which the protecting group is removed by the action of one or both of acid and heat to generate one or more hydroxyl groups or carboxyl groups, and * represents a bonding part;

[0737] [Chemistry 49]

[0738]

[0739] In the above general formula (c-4), R e It is an organic group whose protecting group is removed by the action of either acid, heat or both, and * represents the bonding part with Y1;

[0740] [Chemistry 50]

[0741]

[0742] In the formula, R f It is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and * represents a bonding part.

[0743] [9]: The metal-containing film-forming composition according to any one of [1] to [8], wherein the amount of the (B) cross-linking agent added is 5 to 100 parts by mass based on 100 parts by mass of the (A) metal compound.

[0744]

[10] : The metal-containing film-forming composition according to any one of [1] to [9], wherein the (C) 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 having a boiling point of 180°C or more.

[0745]

[11] : A method for forming a pattern on a processed substrate, comprising the following steps:

[0746] (I-1) After coating a metal-containing film-forming composition as described in any one of [1] to

[10] on a substrate to be processed, heat treatment is performed to form a metal-containing film;

[0747] (I-2) forming a resist upper layer film on the metal-containing film using a photoresist material,

[0748] (I-3) after exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0749] (I-4) using the patterned resist upper layer film as a mask, transferring the pattern to the metal-containing film by dry etching, and

[0750] (I-5) Using the patterned metal-containing film as a mask, the substrate to be processed is processed to form a pattern on the substrate to be processed.

[0751]

[12] : A method for forming a pattern on a processed substrate, comprising the following steps:

[0752] (II-1) forming a resist underlayer film on a substrate to be processed,

[0753] (II-2) coating the metal-containing film-forming composition as described in any one of [1] to

[10] on the resist underlayer film, and then performing a heat treatment to form a metal-containing film;

[0754] (II-3) forming a resist upper layer film on the metal-containing film using a photoresist material,

[0755] (II-4) After exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0756] (II-5) using the patterned resist upper layer film as a mask, transferring the pattern to the metal-containing film by dry etching,

[0757] (II-6) using the metal-containing film having the transferred pattern as a mask, transferring the pattern to the resist underlayer film by dry etching,

[0758] (II-7) The substrate to be processed is processed using the patterned resist underlayer film as a mask to form a pattern on the substrate to be processed.

[0759]

[13] : A method for forming a pattern on a processed substrate, comprising the following steps:

[0760] (III-1) After coating a metal-containing film-forming composition as described in any one of [1] to

[10] on a substrate to be processed, heat treatment is performed to form a metal-containing film;

[0761] (III-2) forming a silicon-containing resist intermediate film on the metal-containing film,

[0762] (III-3) forming a resist upper layer film on the silicon-containing resist intermediate film using a photoresist material,

[0763] (III-4) after exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0764] (III-5) using the patterned resist upper layer film as a mask, transferring the pattern to the silicon-containing resist intermediate film by dry etching,

[0765] (III-6) using the transferred patterned silicon-containing resist intermediate film as a mask, transferring the pattern to the metal-containing film by dry etching, and

[0766] (III-7) The substrate to be processed is processed using the patterned metal-containing film as a mask to form a pattern on the substrate to be processed.

[0767]

[14] : A method for forming a pattern on a processed substrate, comprising the following steps:

[0768] (IV-1) After coating a substrate to be processed with a metal-containing film-forming composition as described in any one of [1] to

[10] , heat treatment is performed to form a metal-containing film;

[0769] (IV-2) forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxide nitride film on the metal-containing film,

[0770] (IV-3) forming an organic thin film on the inorganic hard mask intermediate film,

[0771] (IV-4) forming a resist upper layer film on the organic thin film using a photoresist material,

[0772] (IV-5) After exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0773] (IV-6) using the patterned resist upper layer film as a mask, transferring the pattern to the organic thin film and the inorganic hard mask intermediate film by dry etching,

[0774] (IV-7) using the inorganic hard mask intermediate film to which the pattern has been transferred as a mask, transferring the pattern to the metal-containing film by dry etching, and

[0775] (IV-8) The substrate to be processed is processed using the patterned metal-containing film as a mask to form a pattern on the substrate to be processed.

[0776]

[15] : The pattern forming method of

[14] , wherein the inorganic hard mask intermediate film is formed by a CVD method or an ALD method.

[0777]

[16] : A method for forming a pattern on a substrate to be processed, comprising the following steps:

[0778] (V-1) After coating a metal-containing film-forming composition as described in any one of [1] to

[10] on a substrate to be processed, heat treatment is performed to form a metal-containing film;

[0779] (V-2) forming an organic intermediate film on the metal-containing film,

[0780] (V-3) forming a silicon-containing resist interlayer film, or a combination of an inorganic hard mask interlayer film selected from silicon oxide film, silicon nitride film, and silicon oxide nitride film and an organic thin film on the organic interlayer film,

[0781] (V-4) forming a resist upper film on the silicon-containing resist intermediate film or the organic film using a photoresist material,

[0782] (V-5) After exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0783] (V-6) using the patterned resist upper film as a mask, transferring the pattern to the silicon-containing resist intermediate film, or the organic thin film and the inorganic hard mask intermediate film by dry etching,

[0784] (V-7) using the transferred pattern of the silicon-containing resist interlayer or the inorganic hard mask interlayer as a mask, and transferring the pattern to the organic interlayer by dry etching.

[0785] (V-8) using the organic intermediate film as a mask, transferring a pattern to the metal-containing film by dry etching, and

[0786] (V-9) The substrate to be processed is processed using the patterned metal-containing film as a mask to form a pattern on the substrate to be processed.

[0787]

[17] : A tone reversal pattern forming method is a method for forming a pattern on a processed substrate, comprising the following steps:

[0788] (VI-1) forming a resist underlayer film on a substrate to be processed,

[0789] (VI-2) forming a silicon-containing resist intermediate film, or a combination of an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxide nitride film and an organic thin film on the resist underlayer film,

[0790] (VI-3) forming a resist upper film using a photoresist material on the silicon-containing resist intermediate film or the combination of the inorganic hard mask intermediate film and the organic thin film,

[0791] (VI-4) After exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film,

[0792] (VI-5) using the patterned resist upper film as a mask, transferring the pattern to the silicon-containing resist intermediate film, or the organic thin film and the inorganic hard mask intermediate film by dry etching,

[0793] (VI-6) using the transferred patterned silicon-containing resist interlayer film or inorganic hard mask interlayer film as a mask, transferring the pattern to the resist underlayer film by dry etching,

[0794] (VI-7) coating the metal-containing film-forming composition as described in any one of [1] to

[10] on the patterned resist underlayer film, and then filling the space between the resist underlayer film patterns with the metal-containing film by heat treatment to coat the metal-containing film.

[0795] (VI-8) etching back the metal-containing film covering the patterned resist underlayer film by chemical stripper or dry etching to expose the top surface of the patterned resist underlayer film;

[0796] (VI-9) removing the silicon-containing resist interlayer film or the inorganic hard mask interlayer film remaining on the top surface of the resist underlayer film by dry etching,

[0797] (VI-10) removing the patterned resist underlayer film whose surface is exposed by dry etching to form a reverse pattern of the original pattern on the metal-containing film,

[0798] (VI-11) The metal-containing film having the reverse pattern formed therein is used as a mask to process the substrate to form a reverse pattern on the substrate.

[0799] The present invention is not limited to the above-described embodiments. The above-described embodiments are illustrative, and those having substantially the same configuration and exhibiting the same functions and effects as the technical concept described in the claims of the present invention are all included in the technical scope of the present invention.

[0800] Description of Reference Numerals

[0801] 1: Processed substrate

[0802] 2: Processing layer

[0803] 2a: Pattern (pattern formed on the processed layer)

[0804] 3: Metal-containing films

[0805] 3a: Metal-containing film pattern

[0806] 4: Silicon-containing resist interlayer

[0807] 4a: Silicon-containing resist interlayer pattern

[0808] 5: Resist upper film

[0809] 5a: Resist upper film pattern

[0810] 6: Exposure part

[0811] 7: Resist lower layer film

[0812] 7a: Resist lower film pattern

[0813] 8:Metallic film

[0814] 8a: The metal-containing film pattern after the resist lower film pattern is reversed,

[0815] 9: Base substrate with dense line and space

[0816] 10:Metallic film

[0817] 11: Gap

Claims

1. A metal-containing film-forming composition comprising: (A) a metal compound containing at least one metal selected from the group consisting of Ti, Zr, and Hf, (B) a cross-linking agent containing 2 to 13 carbon cyclic ether structures in the molecule, and (C) Solvent.

2. The metal-containing film-forming composition according to claim 1, wherein The (B) cross-linking agent has two or more epoxy groups or oxetanyl groups in the molecule.

3. The metal-containing film-forming composition according to claim 1, wherein The (B) crosslinking agent is any one of the organic compounds represented by the following formula (1); In the above formula (1), X is an m-valent organic group having 1 to 50 carbon atoms, L is a carbonyl group or a divalent organic group having 1 to 10 carbon atoms, R1 and R2 are each independently a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms, and R 1a It is an alicyclic hydrocarbon group having 3 to 10 carbon atoms, l represents 0 or 1, and m represents 2 to 4.

4. The metal-containing film-forming composition according to claim 3, wherein X in the formula (1) is an m-valent organic group containing one or more of any of a quaternary carbon atom, an aromatic ring, an alicyclic hydrocarbon, or a heterocyclic ring.

5. The metal-containing film-forming composition according to claim 3, wherein X in the formula (1) is any one of the following structures: In the above formula, n is 1 to 5, r is 0 or 1, s is 1 or 2, R3 and R4 are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms which may also contain a halogen atom, R5 is a hydrogen atom, a hydroxyl group or an alkyl group having 1 to 10 carbon atoms, R6 and R7 are each independently a hydrogen atom, a hydroxyl group or an organic group having 1 to 10 carbon atoms which contains an alkyl group, an alkylene group or an alkynyl group, R8 is a hydrogen atom, a hydroxyl group or an organic group having 1 to 10 carbon atoms which contains an alkyl group, an alkylene group or an alkynyl group, * represents a bonding portion with L, and the carbon atoms in the aromatic ring of the above formula may also have a hydroxyl group, a carboxyl group, a vinyl group, an ethynyl group, an amino group, a thioether group, or an alkyl group having 1 to 10 carbon atoms which may also contain these groups as substituents.

6. The metal-containing film-forming composition according to claim 1, wherein The (A) metal compound is a metal compound represented by the following formula (2); Ln a MXn b (2) In the formula, M is any one of Ti, Zr, and Hf; Ln is independently a monodentate ligand or a polydentate ligand having 1 to 30 carbon atoms; Xn is independently selected from a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, -NR a R b The hydrolyzable group R a and R b Each is independently a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; a+b=4, and a and b are integers of 0-4.

7. The metal-containing film-forming composition according to claim 6, wherein The formula (2) is the structure of the following formula (3); M(OR 1A )4 (3) Wherein, M is Ti, Zr, or Hf, R 1A It is a monovalent organic group having 1 to 20 carbon atoms.

8. The metal-containing film-forming composition according to claim 6, wherein The metal compound (A) is a reaction product of a compound derived from the metal compound represented by the formula (2) and an organic compound having 1 to 30 carbon atoms and containing at least one crosslinking group represented by the following general formulas (a-1) to (a-4), (b-1) to (b-4), (c-1) to (c-3) and (d-1) to (d-2); In the general formulas (a-1) to (a-4), R a are independently a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, q represents 0 or 1, and * represents a bonding portion; In this general formula, R b are independently a hydrogen atom or a methyl group, and may be the same or different in the same formula, R c is hydrogen, or a substituted or unsubstituted saturated or unsaturated monovalent organic group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted aralkyl group having 7 to 31 carbon atoms, and * represents a bonding part; In the general formulae (c-1) to (c-3), Y1 is independently a divalent organic group having 1 to 20 carbon atoms, R is a hydrogen atom, a substituted or unsubstituted saturated or unsaturated monovalent organic group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted aralkyl group having 7 to 31 carbon atoms, and R d are independently an organic group represented by the following general formula (c-4) in which the protecting group is removed by the action of one or both of acid and heat to generate one or more hydroxyl groups or carboxyl groups, and * represents a bonding part; In the above general formula (c-4), R e It is an organic group whose protecting group is removed by the action of either acid, heat or both, and * represents the bonding part with Y1; In the formula, R f It is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and * represents a bonding part.

9. The metal-containing film-forming composition according to claim 1, wherein The amount of the (B) crosslinking agent added is 5 to 100 parts by mass based on 100 parts by mass of the (A) metal compound.

10. The metal-containing film-forming composition according to claim 1, wherein The 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 having a boiling point of 180°C or higher.

11. A method for forming a pattern on a processed substrate, comprising the following steps: (I-1) After applying the metal-containing film-forming composition according to any one of claims 1 to 10 on a substrate to be processed, heat treatment is performed to form a metal-containing film; (I-2) forming a resist upper layer film on the metal-containing film using a photoresist material, (I-3) after exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film, (I-4) using the patterned resist upper layer film as a mask, transferring the pattern to the metal-containing film by dry etching, and (I-5) Using the patterned metal-containing film as a mask, the substrate to be processed is processed to form a pattern on the substrate to be processed.

12. A method for forming a pattern on a processed substrate, comprising the following steps: (II-1) forming a resist underlayer film on a substrate to be processed, (II-2) coating the metal-containing film-forming composition according to any one of claims 1 to 10 on the resist underlayer 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) After exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film, (II-5) using the patterned resist upper layer film as a mask, transferring the pattern to the metal-containing film by dry etching, (II-6) using the metal-containing film having the transferred pattern as a mask, transferring the pattern to the resist underlayer film by dry etching, (II-7) The substrate to be processed is processed using the patterned resist underlayer film as a mask to form a pattern on the substrate to be processed.

13. A method for forming a pattern on a processed substrate, comprising the following steps: (III-1) After applying the metal-containing film-forming composition according to any one of claims 1 to 10 on a substrate to be processed, heat treatment is performed to form a metal-containing film; (III-2) forming a silicon-containing resist intermediate film on the metal-containing film, (III-3) forming a resist upper film on the silicon-containing resist intermediate film using a photoresist material, (III-4) exposing the resist upper film to a pattern and then developing the resist upper film using a developer to form a pattern on the resist upper film, (III-5) using the patterned resist upper layer film as a mask, transferring the pattern to the silicon-containing resist intermediate film by dry etching, (III-6) using the transferred patterned silicon-containing resist intermediate film as a mask, transferring the pattern to the metal-containing film by dry etching, and (III-7) The substrate to be processed is processed using the patterned metal-containing film as a mask to form a pattern on the substrate to be processed.

14. A method for forming a pattern on a processed substrate, comprising the following steps: (IV-1) After applying the metal-containing film-forming composition according to any one of claims 1 to 10 onto a substrate to be processed, heat treatment is performed to form a metal-containing film; (IV-2) forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxide nitride film on the metal-containing film, (IV-3) forming an organic thin film on the inorganic hard mask intermediate film, (IV-4) forming a resist upper layer film on the organic thin film using a photoresist material, (IV-5) After exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film, (IV-6) using the patterned resist upper film as a mask, transferring the pattern to the organic thin film and the inorganic hard mask intermediate film by dry etching, (IV-7) using the inorganic hard mask intermediate film to which the pattern has been transferred as a mask, transferring the pattern to the metal-containing film by dry etching, and (IV-8) The substrate to be processed is processed using the patterned metal-containing film as a mask to form a pattern on the substrate to be processed.

15. The pattern forming method according to claim 14, wherein: The inorganic hard mask intermediate film is formed by a CVD method or an ALD method.

16. A method for forming a pattern on a processed substrate, comprising the following steps: (V-1) After applying the metal-containing film-forming composition according to any one of claims 1 to 10 on a substrate to be processed, heat-treating the substrate to form a metal-containing film; (V-2) forming an organic intermediate film on the metal-containing film, (V-3) forming a silicon-containing resist interlayer film, or a combination of an inorganic hard mask interlayer film selected from silicon oxide film, silicon nitride film, and silicon oxide nitride film and an organic thin film on the organic interlayer film, (V-4) forming a resist upper film on the silicon-containing resist intermediate film or the organic film using a photoresist material, (V-5) After exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film, (V-6) using the patterned resist upper film as a mask, transferring the pattern to the silicon-containing resist intermediate film, or the organic thin film and the inorganic hard mask intermediate film by dry etching, (V-7) using the transferred pattern of the silicon-containing resist interlayer or the inorganic hard mask interlayer as a mask, and transferring the pattern to the organic interlayer by dry etching. (V-8) using the organic intermediate film as a mask, transferring a pattern to the metal-containing film by dry etching, and (V-9) The substrate to be processed is processed using the patterned metal-containing film as a mask to form a pattern on the substrate to be processed.

17. A tone reversal pattern forming method is a method for forming a pattern on a processed substrate, comprising the following steps: (VI-1) forming a resist underlayer film on a substrate to be processed, (VI-2) forming a silicon-containing resist intermediate film, or a combination of an inorganic hard mask intermediate film selected from silicon oxide film, silicon nitride film, and silicon oxide nitride film and an organic thin film on the resist underlayer film, (VI-3) forming a resist upper film using a photoresist material on the silicon-containing resist intermediate film or the combination of the inorganic hard mask intermediate film and the organic thin film, (VI-4) After exposing the resist upper layer film to a pattern, developing the resist upper layer film with a developer to form a pattern on the resist upper layer film, (VI-5) using the patterned resist upper film as a mask, transferring the pattern to the silicon-containing resist intermediate film, or the organic thin film and the inorganic hard mask intermediate film by dry etching, (VI-6) using the transferred patterned silicon-containing resist interlayer film or inorganic hard mask interlayer film as a mask, transferring the pattern to the resist underlayer film by dry etching, (VI-7) coating the metal-containing film-forming composition according to any one of claims 1 to 10 on the patterned resist underlayer film, and then filling the space between the resist underlayer film patterns with the metal-containing film by heat treatment to cover the metal-containing film. (VI-8) etching back the metal-containing film covering the patterned resist underlayer film by chemical stripper or dry etching to expose the top surface of the patterned resist underlayer film; (VI-9) removing the silicon-containing resist interlayer film or the inorganic hard mask interlayer film remaining on the top surface of the resist underlayer film by dry etching, (VI-10) removing the patterned resist underlayer film whose surface is exposed by dry etching to form a reverse pattern of the original pattern on the metal-containing film, (VI-11) The metal-containing film having the reverse pattern formed therein is used as a mask to process the substrate to form a reverse pattern on the substrate.

Images