Compound for forming metal-containing film, composition for forming metal-containing film, and patterning process

Abstract

To provide: a compound for forming a metal-containing film having excellent dry etching resistance and also having high filling and planarizing properties; a composition for forming a metal-containing film containing the compound; and a patterning process in which the composition is used.SOLUTION: The present invention is a compound for forming a metal-containing film, where the compound is represented by a general formula (M) in the figure, where R1 and R2 each independently represent an organic group or a halogen atom, and W represents a divalent organic group represented by a general formula (W-1) or (W-2) in the figure.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] As LSIs become more highly integrated and faster, pattern rules are becoming finer at a rapid pace. As the most advanced fine-tuning technology, ArF immersion lithography is being applied to the mass production of devices at the 45nm node and beyond. In addition to ArF immersion exposure, double exposure (double patterning) processes have been put into practical use for the 28nm node and beyond generation, making it possible to form narrow-pitch patterns that exceed the optical limit.

[0003] Furthermore, for device manufacturing at the 20 nm node and below, multiple exposure (multi-patterning) processes are being considered, which create patterns with narrower pitches by repeating exposure and etching three or more times. However, the multiple exposure process increases the number of steps, which leads to longer manufacturing times and a higher frequency of defects, reducing productivity and resulting in a significant increase in costs.

[0004] In recent years, 13.5 nm wavelength vacuum ultraviolet (EUV) lithography has been attracting attention as a promising technology to replace the combined use of ArF immersion lithography and multiple exposure processes. Using this technology, it has become possible to form fine patterns with a half pitch of 25 nm or less in a single exposure.

[0005] On the other hand, in EUV lithography, there is a strong demand for high sensitivity in resist materials to compensate for the insufficient output of the light source. However, the increase in shot noise that accompanies high sensitivity leads to an increase in edge roughness (LER, LWR) of the line pattern, and therefore achieving both high sensitivity and low edge roughness is one of the important challenges in EUV lithography.

[0006] In recent years, the use of metal materials in resist materials has been considered as an attempt to increase the sensitivity of resists and reduce the effects of shot noise. Compounds containing metal elements such as barium, titanium, hafnium, zirconium, and tin have a higher absorbance to EUV light than organic materials that do not contain metals, and are expected to improve the photosensitivity of resists and suppress the effects of shot noise. In addition, metal-containing resist patterns can be combined with an underlayer film made of a non-metallic material to enable high-selectivity etching processing.

[0007] For example, resist materials containing added metal salts or organometallic complexes as described in Patent Documents 1 and 2, and non-chemically amplified resist materials using metal oxide nanoparticles as described in Patent Documents 3 and 4 have been investigated.

[0008] Among them, molecules containing tin are being actively researched because they have excellent absorption of electron beams and extreme ultraviolet rays. In the case of organotin polymers, which are one of them, alkyl ligands are dissociated by light absorption or secondary electrons generated by it, and crosslinking with surrounding chains through oxo bonds enables negative tone patterning that is not removed by organic developers. Such organotin polymers can improve sensitivity while maintaining resolution and line edge roughness, but have not yet reached the level of commercialization (Patent Document 5). In addition, many issues remain, such as insufficient storage stability against changes in resist sensitivity.

[0009] In response to the above-mentioned problems, development of a resist underlayer film using a material containing metal elements such as titanium, hafnium, zirconium, and tin is also being considered. There is no need to improve performance such as improving exposure sensitivity and suppressing sensitivity changes under storage conditions, which are issues with metal-containing resist materials, and by including the above-mentioned metal elements, it is possible to provide a resist underlayer film with excellent dry etching resistance. Patent Document 6 reports that a material using a Ti compound exhibits excellent dry etching resistance against CHF3 / CF4-based gas and CO2 / N2-based gas.

[0010] On the other hand, one of the problems when using a metal compound for a resist underlayer film is embeddability. Although Patent Document 6 does not mention embeddability, metal oxide compounds generally have a large thermal shrinkage during baking, and after high-temperature baking, they induce a significant deterioration in filling properties, so there is a concern that they are insufficient as a resist underlayer film material that requires high flattening properties, embedding properties, and heat resistance properties. Patent Document 7 reports that a metal compound modified with a specific ligand has excellent embeddability, but the bake temperature for the embeddability evaluation carried out is as low as 150°C, and there is a concern that they are insufficient as a resist underlayer film that requires heat resistance (for example, properties against heat treatment that may be performed after the formation of a resist underlayer film). Patent Document 8 provides a resist underlayer film material that has excellent embeddability after baking at 400°C by mixing the metal compound reported in Patent Document 7 with an organic polymer of a specific structure, but since it is a mixed composition of an inorganic metal compound and an organic polymer, there are concerns about poor film formation caused by poor compatibility, deterioration of storage stability, and deterioration of dry etching resistance. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] Patent No. 5708521 [Patent Document 2] Patent No. 5708522 [Patent Document 3] U.S. Patent No. 9,310,684 [Patent Document 4] US Patent Application Publication No. 2017 / 0102612 [Patent Document 5] JP 2021-162865 A [Patent Document 6] Patent No. 6189758 [Patent Document 7] Patent No. 7050137 [Patent Document 8] Special Publication No. 2022-521531 Summary of the Invention [Problem to be solved by the invention]

[0012] The present invention has been made in view of the above circumstances, and aims to provide a compound for forming a metal-containing film that has excellent dry etching resistance compared to conventional organic underlayer film materials and also has high-level filling / planarization properties, a composition for forming a metal-containing film using the compound, and a pattern formation method using the composition. [Means for solving the problem]

[0013] In order to solve the above problems, the present invention provides A compound for forming a metal-containing film, characterized in that the compound is represented by the following general formula (M): [ka] (In the above general formula (M), R1 and R2 each independently represent an organic group or a halogen atom, and W represents a divalent organic group represented by the following general formula (W-1) or (W-2): [ka] (In the general formula (W-1), l is an integer of 2 to 3; R3 and R4 each independently represent a substituted or unsubstituted linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a thiol group, a hydroxyl group, an amino group, a hydrogen atom or a halogen atom; or two of R3 and R4 on the same carbon form a carbonyl group together with the carbon to which they are bonded, and the alkyl group, the alkenyl group, the alkynyl group and the alkoxy group may have an ester group or an amide group. Also, two of R3 and R4 on the same carbon bond to each other to form a ring structure. In the general formula (W-2), R5 is independently a substituted or unsubstituted linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a thiol group, a hydroxyl group, an amino group, or a halogen atom, and the alkyl group, the alkenyl group, the alkynyl group, and the alkoxy group may have an ester group or an amide group, n is an integer of 0 to 1, m is an integer of 0 to 6, and * is a bonding site with -OSn.

[0014] Here, the heteroalkyl group refers to an alkyl group further containing one or more (e.g., 1, 2, 3, or 4) heteroatoms (e.g., oxygen, sulfur, nitrogen, boron, silicon, phosphorus) in its main chain. The heteroatoms may be inserted between adjacent carbon atoms in the parent carbon chain, or between a carbon atom and its parent molecule (i.e., between the bonding points). However, substituted or unsubstituted alkoxy groups having 1 to 20 carbon atoms and substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms and having an ester group or amide group are excluded.

[0015] In this way, if the compound for forming a metal-containing film is capable of bonding with Sn through two hydroxyl groups possessed by catechol, diol, or α-hydroxycarboxylic acid, then two bond cleavage is required when the organic ligand sublimes, resulting in a tin-containing compound with superior heat resistance compared to compounds with normal monovalent ligands, and volume shrinkage that induces deterioration of embeddability can be suppressed. In addition, since the compound contains two organic groups represented by R1 and R2, thermal fluidity can also be imparted. Therefore, even after high-temperature baking, a metal-containing film with excellent film-forming, embedding, and planarization properties can be formed.

[0016] In the above general formula (M), it is preferable that R1 is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted aliphatic unsaturated organic group having 2 to 20 carbon atoms containing one or more double bonds or triple bonds, 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.

[0017] If R1 is as described above, then when baked, radicals are generated by homolytic cleavage of the tin-carbon bond, and a crosslinking reaction occurs due to the radicals, resulting in excellent thermosetting properties, and therefore a metal-containing film that is excellent in film-forming properties, filling properties, and planarization properties can be formed even after high-temperature baking.

[0018] In the above general formula (M), it is preferable that R2 is -OC(=O)R2' (wherein R2' is a monovalent organic group).

[0019] In the above general formula (M), if R2 is -OC(=O)R2', the symmetry of the compound structure is broken, and a metal-containing film with excellent solvent solubility can be formed. In addition, if R2' is -OC(=O)R2', R2' can be freely changed, so if a bulky structure is incorporated, further improvement in solubility and thermal fluidity can be expected, and it is also possible to have a crosslinked structure, so that sublimate can be suppressed and volume shrinkage that induces deterioration of embeddability can be suppressed. As a result, a metal-containing film with excellent film-forming, embedding and flattening properties can be formed even after high-temperature baking.

[0020] In the present invention, R2' is preferably represented by the following general formulae (A-1) to (A-4), (2) or (3). [ka] (In the above general formulae (A-1) to (A-4), Y A1 , Y A2 may be the same or different, and each represents 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, 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. A is a hydrogen atom, 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, 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 A1 is an organic group that generates one or more hydroxyl or carboxyl groups by elimination of a protecting group by the action of either or both of an acid and heat, as represented by the following general formula (1), and * represents a bond with a carbonyl group. [ka] (In the above general formula (1), R A2is an organic group whose protecting group is removed by the action of either acid or heat, or both, and * is Y A1 Or Y A2 ) [ka] (In the general formula (2), X is a divalent organic group having 1 to 31 carbon atoms, B is the following general formula (B), and * represents a bond to a carbonyl group.) [ka] (In the above general formula (B), Y B represents a substituted or unsubstituted divalent saturated aliphatic hydrocarbon group having 1 to 20 carbon atoms or an unsaturated divalent aliphatic hydrocarbon group having 2 to 20 carbon atoms, a substituted or unsubstituted divalent aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted divalent arylalkyl group having 7 to 31 carbon atoms, which may be bonded to an adjacent group via an oxygen atom or an NH group; R B is a hydroxyl group or any of the structures represented by the following general formulas (B-1) to (B-3). * represents the bond with the carbonyl group. [ka] (In the above general formulas (B-1) to (B-3), R B1 is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, q is 0 or 1, * is Y B ) [ka] (In the general formula (3), X is a divalent organic group having 1 to 31 carbon atoms, C is a group represented by the following general formulas (C-1) to (C-4), and * represents a bond to a carbonyl group.) [ka] (In the above general formulas (C-1) and (C-3), R C1 are each independently a hydrogen atom or a methyl group, and in the same formula, they may be the same or different. In (C-3) to (C-4), R C2is a hydrogen atom, or a substituted or unsubstituted saturated or unsaturated monovalent aliphatic hydrocarbon 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. * represents the bond to the carbonyl group.)

[0021] If R2' is a structure represented by the above general formulas (A-1) to (A-4), the structure contains a bulky thermoacid labile group, and therefore the thermal fluidity can be improved. Furthermore, when this is used in a metal-containing film-forming composition, the thermoacid labile group is eliminated during baking, and a hydroxyl group or a carboxyl group is generated. The OH and α-hydrogen of the carboxylic acid thus generated are likely to react with radicals generated by the cleavage of the tin-carbon bond during baking, and a crosslinking reaction occurs, resulting in excellent thermosetting properties, which can suppress volume shrinkage that induces deterioration of flatness and embeddability, and a metal-containing film with excellent film-forming properties and flattening / embedding properties can be formed even after high-temperature baking.

[0022] Furthermore, if R2' has a structure represented by the above general formula (2), it contains a hydroxyl group or any of the crosslinking groups represented by the above general formulas (B-1) to (B-3) at its terminal. Therefore, when this is used in a composition for forming a metal-containing film, it easily reacts with the radicals generated by the cleavage of the tin-carbon bond when baked, causing a crosslinking reaction. Furthermore, since a crosslinking reaction occurs even with only these crosslinking groups, the composition has excellent thermosetting properties and can suppress volume shrinkage that induces deterioration of flatness and fillability. Thus, a metal-containing film having excellent film-forming properties and flattening properties / filling properties can be formed even after high-temperature baking.

[0023] Furthermore, if R2' has a structure represented by the above general formula (3), it contains the structures represented by (C-1) to (C-4), has a high crosslinking group density, and has excellent thermosetting properties. Therefore, when this is used in a composition for forming a metal-containing film, it is possible to form a metal-containing film that has small volume shrinkage during baking and has excellent film-forming properties and planarizing properties / filling properties even after high-temperature baking.

[0024] In the present invention, Y in the general formulas (A-1) to (A-4) A1It is preferable that X in the general formula (2) or X in the general formula (3) is a substituted or unsubstituted unsaturated hydrocarbon having 2 to 20 carbon atoms.

[0025] Y in the above general formulas (A-1) to (A-4) A1 When X in the general formula (2) or X in the general formula (3) is a substituted or unsubstituted unsaturated hydrocarbon having 2 to 20 carbon atoms, the thermosetting property of the metal-containing film-forming compound can be further improved.

[0026] In the present invention, Y in the general formulas (A-1) to (A-4) A1 In addition, it is possible to provide a compound for forming a metal-containing film, in which X in the general formula (2) or X in the general formula (3) is represented by the following general formula (4). [ka] (In the general formula (4), R a , R b and R C is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms, and R a and R b may be bonded to form a cyclic substituent. *1 and *2 each represent a bond to a carbonyl group, and the substitution positions of *1 and *2 may be reversed.)

[0027] A compound for forming a metal-containing film having such a structure is capable of achieving a high degree of both thermal fluidity and thermosetting property, and when used in a composition for forming a metal-containing film, a metal-containing film exhibiting superior planarization properties / filling properties can be formed.

[0028] The ratio Mw / Mn of the weight average molecular weight Mw and the number average molecular weight Mn of the metal-containing film-forming compound, calculated as polystyrene, by gel permeation chromatography, is preferably 1.00≦Mw / Mn≦1.50.

[0029] A compound for forming a metal-containing film having a dispersity in such a range has even better thermal fluidity, and therefore when incorporated into a composition for forming a metal-containing film, it is possible not only to satisfactorily fill in the fine structure formed on the substrate, but also to form a resist underlayer film that flattens the entire substrate.

[0030] The present invention also provides a composition for forming a metal-containing film that functions as a resist underlayer film material used in semiconductor manufacturing, the composition comprising the above-mentioned (a) compound for forming a metal-containing film and (b) an organic solvent.

[0031] Such a composition for forming a metal-containing film contains an organotin compound that has excellent solvent solubility, heat resistance, and thermal fluidity, and therefore can form a metal-containing film that has excellent dry etching resistance compared to conventional organic underlayer film materials and also has advanced filling / planarization properties.

[0032] The composition of the present invention is a composition for forming a metal-containing film that can be used as a resist underlayer film in a multi-layer resist method, and can further contain one or more of (c) a crosslinking agent, (d) a surfactant, (e) a flowability promoter, and (f) an acid generator.

[0033] Such a composition is endowed with favorable properties by adding the above-mentioned components to the above-mentioned metal-containing film-forming compound, and thus has more suitable high-level filling / planarizing properties.

[0034] In the present invention, the (b) organic solvent 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.

[0035] In such a composition, the metal-containing film-forming compound is given thermal fluidity by adding a high boiling point solvent, so that the metal-containing film-forming composition has higher filling / flattening properties. Note that the boiling point in this specification is a value at 1 atmosphere (1013 hPa).

[0036] The present invention also provides a method for forming a pattern on a workpiece substrate, comprising the steps of: (I-1) a step of applying the composition for forming a metal-containing film of the present invention onto a substrate to be processed, followed by heat treatment to form a metal-containing film; (I-2) forming a resist top layer film on the metal-containing film using a photoresist material; (I-3) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (I-4) a step of transferring the pattern to the metal-containing film by dry etching using the resist top layer film on which the pattern is formed as a mask; and (I-5) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. The present invention provides a pattern forming method comprising the steps of:

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

[0038] The present invention also provides a method for forming a pattern on a workpiece substrate, comprising the steps of: (II-1) a step of applying the composition for forming a metal-containing film of the present invention onto a substrate to be processed, followed by heat treatment to form a metal-containing film; (II-2) forming a resist intermediate film on the metal-containing film; (II-3) forming a resist upper layer film on the resist intermediate film using a photoresist material; (II-4) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (II-5) a step of transferring the pattern to the resist intermediate film by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (II-6) a step of transferring a pattern to the metal-containing film by dry etching using the resist intermediate film to which the pattern has been transferred as a mask; and (II-7) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. A pattern forming method comprising the steps of:

[0039] The pattern formation method using the three-layer resist process described above makes it possible to form fine patterns on a workpiece with high precision.

[0040] The present invention also provides a method for forming a pattern on a workpiece substrate, comprising the steps of: (III-1) A step of applying the composition for forming a metal-containing film of the present invention onto a substrate to be processed and then heat-treating the composition to form a metal-containing film; (III-2) forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film on the metal-containing film; (III-3) forming an organic thin film on the inorganic hard mask intermediate film; (III-4) forming a resist top layer film on the organic thin film using a photoresist material; (III-5) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (III-6) a step of transferring a pattern to the organic thin film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (III-7) A step of transferring a pattern to the metal-containing film by dry etching using the inorganic hard mask intermediate film to which the pattern has been transferred as a mask; and (III-8) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. The present invention provides a pattern forming method comprising the steps of:

[0041] The pattern formation method using the four-layer resist process described above makes it possible to form fine patterns on a workpiece with high precision.

[0042] In this case, the inorganic hard mask is preferably formed by a CVD method or an ALD method.

[0043] 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 higher accuracy.

[0044] The present invention also provides a method for forming a pattern on a workpiece substrate, comprising the steps of: (IV-1) forming a resist underlayer film on a substrate to be processed; (IV-2) a step of applying the composition for forming a metal-containing film of the present invention onto the resist underlayer film, followed by heat treatment to form a metal-containing film; (IV-3) forming a resist upper layer film on the metal-containing film using a photoresist material, or forming an organic adhesion film on the metal-containing film by spin coating, and forming a resist upper layer film thereon using a photoresist material; (IV-4) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (IV-5) a step of transferring a pattern to the metal-containing film, or the organic adhesion film and the metal-containing film, by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (IV-6) a step of transferring a pattern to the resist underlayer film by dry etching using the metal-containing film to which the pattern has been transferred as a mask; and (IV-7) A step of processing the substrate to be processed using the resist underlayer film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. A pattern forming method comprising the steps of:

[0045] By using the pattern forming method using the multi-layer resist process, a fine pattern can be formed on a workpiece with high precision.

[0046] The present invention also provides a method for forming a pattern on a workpiece substrate, comprising the steps of: (V-1) a step of forming a resist underlayer film on a substrate to be processed; (V-2) a step of forming a 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 oxynitride film and an organic thin film on the resist underlayer film; (V-3) forming a resist upper layer film on the resist intermediate film or on a combination of the inorganic hard mask intermediate film and an organic thin film using a photoresist material; (V-4) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (V-5) a step of transferring a pattern to the resist intermediate film, or the organic thin film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (V-6) a step of transferring a pattern to the resist underlayer film by dry etching using the resist intermediate film or the inorganic hard mask intermediate film to which the pattern has been transferred as a mask; (V-7) a step of applying the composition for forming a metal-containing film of the present invention onto the resist underlayer film on which the pattern has been formed, and then heat-treating the composition to form a metal-containing film, thereby filling spaces between the resist underlayer film patterns with the metal-containing film; (V-8) a step of etching back the metal-containing film covering the resist underlayer film on which the pattern is formed by a chemical stripper or dry etching to expose an upper surface of the resist underlayer film on which the pattern is formed; (V-9) a step of removing the resist intermediate film or the hard mask intermediate film remaining on the upper surface of the resist underlayer film by dry etching; (V-10) a step of removing the resist underlayer film on which the pattern is formed and the surface is exposed by dry etching to form a reverse pattern of the original pattern on the metal-containing film; (V-11) A step of processing the substrate to be processed using the metal-containing film on which the reverse pattern is formed as a mask to form a reverse pattern on the substrate to be processed. The present invention provides a pattern forming method comprising the steps of:

[0047] The above-described method for forming a pattern using a reversal process makes it possible to form a fine pattern on a workpiece with even greater precision.

[0048] In this case as well, the inorganic hard mask is preferably formed by a CVD method or an ALD method.

[0049] 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 higher accuracy. Effect of the Invention

[0050] As described above, the metal-containing film-forming compound of the present invention is a metal-containing film-forming compound having excellent heat resistance because it is bonded to Sn through two hydroxyl groups of catechol, diol, or α-hydroxycarboxylic acid as shown in the above general formula (M). In addition, since it contains two organic groups, it is a metal-containing film-forming compound having excellent thermal fluidity, and the performance can be tuned by changing the structure of the organic groups. When this is used in a metal-containing film-forming composition, it is possible to suppress volume shrinkage that induces deterioration of embedding properties, and to form a metal-containing film such as a resist underlayer film material having excellent film-forming properties and planarization properties / embedding properties even after high-temperature baking. In particular, in fine patterning processes using multi-layer resist methods in semiconductor device manufacturing processes, it is possible to fill without causing defects such as voids or peeling, even on substrates having areas that are difficult to fill / planarize, such as dense areas of high aspect ratio fine pattern structures such as those in DRAM memories, which are becoming increasingly miniaturized.In addition, since it has superior dry etching resistance compared to conventional coating-type organic resist underlayer film materials, it is possible to form fine patterns on the workpiece with even greater precision than with organic resist underlayer films. In addition, the metal-containing film-forming composition containing the metal-containing film-forming compound of the present invention contains tin atoms that have high EUV light absorption, and therefore has a sensitizing effect due to secondary electrons generated from the tin atoms during exposure. Furthermore, since tin atoms have a large atomic weight, they are highly effective in suppressing acid diffusion from the upper resist layer into the resist underlayer film, and thus have the characteristic of being able to achieve high sensitivity while maintaining the LWR performance that the resist upper layer film originally has. [Brief description of the drawings]

[0051] [Figure 1] FIG. 2 is an explanatory diagram of an example (three-layer resist process) of the pattern forming method of the present invention. [Diagram 2] FIG. 2 is an explanatory diagram of an example of a tone reversal pattern formation method of the present invention (reversal of an SOC pattern in a three-layer resist process). [Diagram 3] FIG. 1 is an explanatory diagram of a method for evaluating embedding characteristics. [Figure 4] FIG. 1 is an explanatory diagram of a flattening characteristic evaluation method. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0052] As described above, in a fine patterning process using a multilayer resist method, there has been a demand for the development of a composition for forming a metal-containing film that has excellent embedding ability and flatness and is used to form a resist underlayer film that can transfer a resist pattern to a substrate to be processed with higher precision, and a compound for forming a metal-containing film that is useful for said composition.

[0053] The present inventors have focused on organotin compounds that are expected to play an active role in the EUV exposure generation and have conducted intensive research. As described above, tin atoms, which have high light absorption, have a sensitizing effect due to secondary electrons generated from them during exposure, and have the characteristic that the resist top layer film can be made highly sensitive while maintaining the inherent LWR performance. On the other hand, the organotin compounds considered as resist top layers have poor heat resistance and undergo rapid volume shrinkage during baking, making it difficult to fill in steps on the substrate to be processed and flatten it after high-temperature baking. The present inventors thought that if a diol / catechol-based compound can bond with divalent tin in one molecule, the bond is less likely to break when baked, and heat resistance can be improved. In addition, since it contains two organic groups that are not involved in the bond with the diol / catechol system, it becomes a metal-containing film-forming compound with excellent solubility and thermal fluidity, and further, it was thought that it is possible to tune the performance by appropriately adjusting the structure of the organic group.

[0054] As a result of further intensive research, the inventors have found that a compound for forming a metal-containing film represented by the above general formula (M) can suppress rapid volumetric shrinkage during baking and has excellent thermal fluidity, and therefore serves as a compound for forming a metal-containing film having excellent film-forming properties, filling properties, and planarization properties, thereby completing the present invention.

[0055] That is, the present invention relates to a compound for forming a metal-containing film, characterized in that the compound is represented by the following general formula (M): [ka] (In the above general formula (M), R1 and R2 each independently represent an organic group or a halogen atom, and W represents a divalent organic group represented by the following general formula (W-1) or (W-2): [ka] (In the general formula (W-1), l is an integer of 2 to 3; R3 and R4 each independently represent a substituted or unsubstituted linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a thiol group, a hydroxyl group, an amino group, a hydrogen atom or a halogen atom; or two of R3 and R4 on the same carbon form a carbonyl group together with the carbon to which they are bonded, and the alkyl group, the alkenyl group, the alkynyl group and the alkoxy group may have an ester group or an amide group. In addition, when two of R3 and R4 on the same carbon are bonded, In the general formula (W-2), R5 is independently a substituted or unsubstituted linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a thiol group, a hydroxyl group, an amino group, or a halogen atom, and the alkyl group, the alkenyl group, the alkynyl group, and the alkoxy group may have an ester group or an amide group, n is an integer of 0 to 1, m is an integer of 0 to 6, and * is a bonding site with -OSn.

[0056] The present invention will be described in detail below, but the present invention is not limited thereto.

[0057] <Compounds for forming metal-containing films> The compound for forming a metal-containing film of the present invention is a compound for forming a metal-containing film, characterized in that it is represented by the following general formula (M). [ka] (In the above general formula (M), R1 and R2 each independently represent an organic group or a halogen atom, and W represents a divalent organic group represented by the following general formula (W-1) or (W-2): [ka] (In the general formula (W-1), l is an integer of 2 to 3; R3 and R4 each independently represent a substituted or unsubstituted linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a thiol group, a hydroxyl group, an amino group, a hydrogen atom or a halogen atom; or two of R3 and R4 on the same carbon form a carbonyl group together with the carbon to which they are bonded, and the alkyl group, the alkenyl group, the alkynyl group and the alkoxy group may have an ester group or an amide group. In addition, when two of R3 and R4 on the same carbon are bonded, In the general formula (W-2), R5 is independently a substituted or unsubstituted linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a thiol group, a hydroxyl group, an amino group, or a halogen atom, and the alkyl group, the alkenyl group, the alkynyl group, and the alkoxy group may have an ester group or an amide group, n is an integer of 0 to 1, m is an integer of 0 to 6, and * is a bonding site with -OSn.

[0058] In the above general formula (M), R1 and R2 are each independently an organic group or a halogen group, and from the viewpoint of raw material availability and synthesis, R1 and R2 are preferably an alkyl group, an ester group, an alkoxy group, or a chloro group, and from the viewpoint of solvent solubility, R1 and R2 preferably have different structures in the same compound.Furthermore, from the viewpoint of thermal fluidity, R1 and R2 are preferably a combination of an alkyl group and an ester group.

[0059] In the above general formula (W-1), R3 and R4 are each independently a substituted or unsubstituted linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a thiol group, a hydroxyl group, an amino group, a hydrogen atom, or a halogen atom; or two of R3 and R4 on the same carbon atom are carbonyl groups together with the carbon to which they are bonded, and the alkyl group, the alkenyl group, the alkynyl group, and the alkoxy group may have an ester group or an amide group. In addition, R3 and R4 on the same carbon may be bonded to form a ring structure, or R3 and R4 on adjacent carbons may be bonded to form a ring structure, but from the viewpoint of crosslinkability and heat resistance, it is preferable that they are an unsaturated hydrocarbon group or an organic group having a hydroxyl group.

[0060] Specific examples of the above general formula in which R3 and R4 are independent include, but are not limited to, the following: In the following formula, * represents a bond. [ka]

[0061] Specific examples of the above general formula (W-1) in which R3 and R4 are bonded to form a ring structure include, but are not limited to, the following: In the following formula, * represents a bond to an oxygen atom. [ka]

[0062] Two of R3 and R4 on the same carbon may form a carbonyl group together with the carbon to which they are bonded, and the above alkyl group, alkenyl group, alkynyl group, and alkoxy group may have an ester group or an amide group.

[0063] When R3 and R4 on the same carbon atom simultaneously become hydroxyl groups, a gem-diol group is formed, which, when dehydrated, becomes a carbonyl group together with the carbon to which they are bonded. In other words, the divalent organic group represented by formula (W-1) may be a divalent organic group containing such a carbonyl group. When R3 and R4 on the same carbon atom form a carbonyl group together with the carbon to which they are bonded, it is preferable that the α-hydroxycarboxylic acid is an α-hydroxycarboxylic acid in which l in the above general formula (W-1) is 2. Examples of the α-hydroxycarboxylic acid include any substituted compounds of hydroxyacetic acid (glycolic acid) such as lactic acid, 2-hydroxybutyric acid, tartaric acid, malic acid, citric acid, isocitric acid, mandelic acid, and benzilic acid. In this case, the α-position of the hydroxyacetic acid may be substituted with a hydrocarbon group having 1 to 30 carbon atoms which may contain an aromatic ring such as a benzene ring, and the aromatic ring may be further substituted with a hydroxyl group.

[0064] In the above general formula (W-1), l is an integer of 2 to 3, and is preferably 2 from the viewpoints of compound stability and raw material availability.

[0065] From the viewpoints of raw material availability, heat resistance, and thermal fluidity, the above general formula (W-1) preferably has the following structure: In the following formula, * represents a bond to an oxygen atom. [ka]

[0066] In formula (W-2), R5 is independently a substituted or unsubstituted linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a thiol group, a hydroxyl group, an amino group, or a halogen atom, and the alkyl group, the alkenyl group, the alkynyl group, and the alkoxy group may have an ester group or an amide group, and from the viewpoint of heat resistance, are preferably an organic group containing an unsaturated hydrocarbon or an organic group having a hydroxyl group.

[0067] n is an integer of 0 to 1, and m is an integer of 0 to 6. From the viewpoints of obtaining the raw material and increasing the tin content, n is preferably 0, and m is preferably 1. * is a bond to —OSn.

[0068] Specific examples of R5 in the above general formula (W-2) include, but are not limited to, the following: In the following formula, * represents a bond to the aromatic ring. [ka]

[0069] From the viewpoints of raw material availability, heat resistance, and thermal fluidity, the above general formula (W-2) preferably has the following structure. [ka]

[0070] In the above general formula (M), R1 is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted aliphatic unsaturated organic group having 2 to 20 carbon atoms containing one or more double bonds or triple bonds, 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 from the viewpoint of suppressing sublimates, an unsubstituted alkyl group having 1 to 20 carbon atoms is more preferable, and from the viewpoint of easy availability of raw materials, an n-butyl group is particularly preferable.

[0071] Such a compound for forming a metal-containing film contains an Sn-alkyl bond, and therefore when baked, the bond is cleaved to generate radicals, which then initiate a crosslinking reaction. As a result, the compound has excellent thermosetting properties, and therefore can form a metal-containing film, such as a resist underlayer film material, that has excellent film-forming properties, filling properties, and planarization properties, even after high-temperature baking.

[0072] Furthermore, in the above general formula (M), it is preferable that R2 is -OC(=O)R2' from the viewpoint of solvent solubility.

[0073] Such a compound for forming a metal-containing film can provide a resist underlayer film with excellent planarization properties because the compound is asymmetric and has excellent solvent solubility and excellent thermal fluidity. In addition, -OC(=O)R2' allows R2' to be freely changed, which allows an increase in molecular weight and a crosslinked structure to be formed, thereby suppressing sublimates and suppressing volume shrinkage that induces deterioration of embedding properties, and can form a metal-containing film with excellent film-forming properties, embedding properties, and planarization properties even after high-temperature baking.

[0074] In the above R2, R2' is preferably represented by the following general formulae (A-1) to (A-4), (2) or (3). [ka] (In the above general formulas (A-1) to (A-4), Y A1 , Y A2may be the same or different, and each represents 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, 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. A is a hydrogen atom, 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, 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 A1 is an organic group that generates one or more hydroxyl or carboxyl groups by elimination of a protecting group by the action of either or both of an acid and heat, as represented by the following general formula (1), and * represents a bond with a carbonyl group. [ka] (In the above general formula (1), R A2 is an organic group whose protecting group is removed by the action of either acid or heat, or both, and * is Y A1 Or Y A2 )

[0075] In the above general formulas (A-1) to (A-4), Y A1 , Y A2 may be the same or different, and each represents a substituted or unsubstituted saturated divalent hydrocarbon group having 1 to 20 carbon atoms or an unsaturated divalent hydrocarbon group having 2 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. A is a hydrogen atom, 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, 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 A1 is an organic group which, when subjected to the action of an acid or heat, or both, releases a protecting group to generate one or more hydroxyl or carboxyl groups.

[0076] In the above general formulas (A-2) to (A-4), Y A2Preferred examples of the structure include, but are not limited to, the structures shown below. a is R A1 The joint with * b represents the other bond. [ka]

[0077] In the above general formula (A-3), R A represents a hydrogen atom, 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, 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 is preferably a hydrogen atom from the viewpoints of suppressing sublimate formation and increasing the Sn content.

[0078] In the above general formula (1), R A2 represents an organic group from which a thermoacid labile group is eliminated by the action of either or both of an acid and heat, and is preferably a tertiary hydrocarbyl group, an acyl group, or a group which forms an acetal structure together with the adjacent oxygen atom, and particularly preferably a tertiary hydrocarbyl group.

[0079] The tertiary hydrocarbyl group preferably has 4 to 20 carbon atoms, and is particularly preferably a tert-butyl group from the viewpoints of suppressing sublimates due to thermal decomposition products and easiness of raw material procurement. Specific examples include, but are not limited to, the following. In the following formula, * represents a bond to an oxygen atom. [ka]

[0080] [ka]

[0081] [ka]

[0082] [ka]

[0083] The acyl group is not particularly limited, but examples thereof include formyl, acetyl, propionyl, butyryl, acryloyl, methacryloyl, malonyl, benzoyl, and naphthoyl groups.

[0084] The group that forms the acetal structure is not particularly limited as long as it is an organic group in which an unstable group is eliminated or cleaved by the action of either or both of an acid and heat. Specific examples of the group that forms the acetal structure include, but are not limited to, the following. In the following formula, * represents a bond to an oxygen atom. [ka]

[0085] [ka]

[0086] [ka]

[0087] Such a compound for forming a metal-containing film has excellent solvent solubility and thermal fluidity. A1 Since it contains thermoacid labile groups, when it is used in a composition for forming a metal-containing film, the tin content increases as these groups are eliminated during baking, resulting in a compound for forming a metal-containing film with excellent dry etching resistance. Furthermore, the hydroxyl and carboxyl groups generated by the elimination react easily with the radicals generated by the cleavage of the tin-carbon bond during baking due to the presence of terminal OH and α-hydrogen, causing a crosslinking reaction, and since it has excellent thermosetting properties, it is possible to suppress volume shrinkage, and even after high-temperature baking, it is possible to form a metal-containing film with excellent film-forming properties and planarization / filling properties.

[0088] In the metal-containing film formed using an organotin compound, the organic group bonded to the Sn atom via a C atom is dissociated during baking to generate radicals, and the generated radicals form -Sn-O-Sn- bonds, initiating a condensation polymerization reaction, which progresses the hardening of the metal-containing film. On the other hand, since the organic group is eliminated simultaneously with the above reaction, a large film shrinkage occurs during baking. However, the above compound has a thermoacid labile group at the end, and the thermoacid labile group is eliminated during baking to generate a hydroxyl group or a carboxyl group, and the OH or α-hydrogen at the end of these groups easily reacts with the radicals, causing a crosslinking reaction as shown in the following reaction formula. Since the compound has at least one such organic group, it is possible to suppress the entire organic group from thermally decomposing and sublimating, and since the compound has excellent thermal fluidity, it is possible to form a metal-containing film with excellent embeddability. [ka]

[0089] [ka] (In the above general formula (2), X is a divalent organic group having 1 to 31 carbon atoms, B is the following general formula (B), and * represents a bond to a carbonyl group.) [ka] (In the above general formula (B), Y B represents 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 (preferably a divalent aliphatic hydrocarbon group), a substituted or unsubstituted divalent aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted divalent arylalkyl group having 7 to 31 carbon atoms, which may be bonded to an adjacent group via an oxygen atom or an NH group; B is a hydroxyl group or any of the structures represented by the following general formulas (B-1) to (B-3). B R B In addition, it may further have a hydroxyl group. * represents the bond with the carbonyl group.) [ka] (In the above general formulas (B-1) to (B-3), R B1 is a hydrogen atom or a monovalent organic group having a value of 1 to 10, q is 0 or 1, * is Y B )

[0090] In the above general formula (2), X is a divalent organic group having 1 to 31 carbon atoms, B is the following general formula (B), and * represents a bond to a carbonyl group. B is a saturated divalent organic group having 1 to 20 carbon atoms or an unsaturated divalent organic group having 2 to 20 carbon atoms, a substituted or unsubstituted divalent aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted divalent arylalkyl group having 7 to 31 carbon atoms; R B is preferably a hydroxyl group or any of the structures represented by the following general formulas (B-1) to (B-3). B1 is a hydrogen atom or a monovalent organic group of 1 to 10, and is preferably a hydrogen atom from the viewpoint of suppressing sublimate formation.

[0091] Preferred structures of the above general formula (B) include, but are not limited to, the structures shown below. In the following formulas, * represents a bond to a carbonyl group. The following examples also represent possible structural isomers. [ka]

[0092] Such a compound for forming a metal-containing film has excellent solvent solubility and thermal fluidity. B Since these compounds contain hydroxyl groups or unsaturated bonds, when they are used in a composition for forming a metal-containing film, they undergo a crosslinking reaction during baking, resulting in excellent thermosetting properties. Furthermore, the crosslinking reaction is accelerated by reacting with radicals generated by the cleavage of tin-carbon bonds, and because of their excellent thermosetting properties, volumetric shrinkage can be suppressed, and a metal-containing film that has excellent film-forming properties and planarization properties / filling properties can be formed even after high-temperature baking.

[0093] [ka] (In the above general formula (3), X is a divalent organic group having 1 to 31 carbon atoms, C is any of the following general formulae (C-1) to (C-4), and * represents a bond to a carbonyl group.) [ka] (In the above general formulas (C-1) and (C-3), R C1 is a hydrogen atom or a methyl group, and they may be the same or different in the same formula. C2 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. * represents the bond to the carbonyl group.)

[0094] In the above general formula (3), X is a divalent organic group having 1 to 31 carbon atoms, and specific examples thereof include a substituted or unsubstituted saturated divalent hydrocarbon group having 1 to 20 carbon atoms or an unsaturated divalent hydrocarbon group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, and a substituted or unsubstituted arylalkyl group having 7 to 31 carbon atoms. C is the above general formulas (C-1) to (C-4), and in (C-1) and (C-3), R C1 From the viewpoint of thermal fluidity, R is preferably a methyl group, and from the viewpoint of curability, R is preferably a hydrogen atom. C2 From the viewpoint of thermal fluidity, the above-described structure other than a hydrogen atom is preferable.

[0095] In the above general formulas (C-1) to (C-4), R C2 Preferred structures of the formula include, but are not limited to, the structures shown below: In the formula, * represents a bond to the nitrogen atom. [ka]

[0096] A compound for forming a metal-containing film having such a structure contains an organic group represented by the above general formula (3), and therefore is a compound for forming a metal-containing film with excellent solvent solubility and heat resistance. Furthermore, since it contains any of the structures represented by the above general formulas (C-1) to (C-4) at its end, it has a high crosslinking group density, can reduce rapid volumetric shrinkage during baking, and has good thermal fluidity, and therefore can form a metal-containing film with excellent filling / planarization properties.

[0097] Y in the above general formulas (A-1) to (A-4) A1 Specific examples of the structure of X in the above general formula (2) or X in the above general formula (3) include, but are not limited to, the structures shown below. In the following formulas, * represents the bond to the carbon atom of the carbonyl group or * in formulas (A-1) to (A-4), (2) and (3). [ka]

[0098] Y in the above general formulas (A-1) to (A-4) A1 In the above-mentioned general formula (2), or in the above-mentioned general formula (3), X is a substituted or unsubstituted unsaturated hydrocarbon having 2 to 20 carbon atoms.

[0099] Y in the above general formulas (A-1) to (A-4) A1 When X in the general formula (2) or X in the general formula (3) is a substituted or unsubstituted unsaturated hydrocarbon having 2 to 20 carbon atoms, the thermosetting property of the metal-containing film-forming compound can be further improved.

[0100] In addition, Y in the above general formulas (A-1) to (A-4) A1 In addition, it is possible to provide a metal-containing film-forming compound, characterized in that X in the above general formula (2) or X in the above general formula (3) is represented by the following general formula (4). [ka] (In the above general formula (4), R a , R b and R C is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms, and R a and R b may be bonded to form a cyclic substituent. *1 and *2 each represent the bond to the carbonyl group, and *1 and *2 may be reversed.)

[0101] Carboxylic acid raw materials containing the above general formula (4) can be synthesized by ring-opening an acid anhydride, but when an asymmetric carboxylic acid anhydride is ring-opened, it becomes a mixture of two types, resulting in the above-mentioned bond type. The presence of such an isomer can suppress crystallinity, and is expected to improve solvent solubility and thermal fluidity, thereby improving planarization characteristics. [ka]

[0102] In the above general formula (4), R a , R b and R C is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms, and R a and R b may be bonded to form a cyclic substituent, and is particularly preferably a hydrogen atom from the viewpoint of suppressing sublimates.

[0103] The metal-containing film-forming compound is preferably characterized in that the ratio Mw / Mn of the weight average molecular weight Mw and the number average molecular weight Mn in terms of polystyrene measured by gel permeation chromatography is 1.00≦Mw / Mn≦1.50.

[0104] By definition, if it is a monomolecular compound, Mw / Mn is 1.00, but due to the separation characteristics of gel permeation chromatography, the measured value may exceed 1.00. Generally, it is extremely difficult for a polymer having repeating units to approach Mw / Mn=1.00 unless a special polymerization method is used, and there is a distribution of Mw, resulting in a Mw / Mn value exceeding 1. In the present invention, 1.00≦Mw / Mn≦1.50 is defined as an index showing monomolecularity in order to distinguish between monomolecular compounds and polymers.

[0105] A compound for forming a metal-containing film having a dispersity in such a range has even better thermal fluidity, and therefore when incorporated into a composition for forming a metal-containing film, it is possible not only to satisfactorily fill in the fine structure formed on the substrate, but also to form a resist underlayer film that flattens the entire substrate.

[0106] <Synthesis of compounds for forming metal-containing films> The method for obtaining the compound for forming a metal-containing film of the present invention may be a known synthesis method and is not particularly limited. For example, it can be prepared by the method described in JP-A-5-123579 and JP-A-52-153913. Specifically, a Sn(IV) compound capable of being derived into a target metal-containing film-forming compound (tin compound) is reacted (such as a ligand exchange reaction) with a diol compound such as catechol or α-hydroxycarboxylic acid or a precursor thereof in a suitable solvent such as toluene, and after completion of the reaction, the solvent and by-products are removed under suitable conditions such as reduced pressure to obtain the target compound. If necessary, an asymmetric compound can also be obtained by carrying out the above reaction by adding a carboxylic acid.

[0107] <Metal-containing film forming composition> The present invention also provides a composition for forming a metal-containing film that functions as a resist underlayer film material used in semiconductor manufacturing, the composition comprising the above-mentioned (a) compound for forming a metal-containing film and (b) an organic solvent.

[0108] Such a composition for forming a metal-containing film contains an organotin compound that has excellent heat resistance and thermal fluidity, and therefore can form a metal-containing film such as a resist underlayer film material that has excellent dry etching resistance compared to conventional organic underlayer film materials and also has advanced filling / planarization properties.

[0109] Hereinafter, components contained in the composition for forming a metal-containing film of the present invention other than the above (a) compound for forming a metal-containing film will be described.

[0110] <(b) Organic solvent> The (b) organic solvent that can be used in the metal-containing film-forming composition of the present invention is not particularly limited as long as it dissolves or disperses the above-mentioned (a) metal-containing film-forming compound, (c) crosslinking agent, (d) surfactant, (e) flow promoter, (f) acid generator, and other additives.

[0111] Specifically, the organic solvents described in paragraphs

[0091] to

[0092] of JP 2007-199653 A can 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, γ-butyrolactone, or a mixture containing one or more of these is preferably used.

[0112] (High boiling point solvent) In the composition for forming a metal-containing film (composition for forming a resist underlayer film) of the present invention, the (b) organic solvent may be used as a mixture of one or more organic solvents having a boiling point (value at 1 atmospheric pressure (1013 hPa)) of less than 180°C and one or more organic solvents (high boiling point solvents) having a boiling point of 180°C or higher.

[0113] The high boiling point solvent is not particularly limited as long as it can dissolve each component of the metal-containing film forming composition of the present invention, and may be any of hydrocarbons, alcohols, ketones, esters, ethers, chlorine-based solvents, etc., but specific examples include 1-octanol, 2-ethylhexanol, 1-nonanol, 1-decanol, 1-undecanol, ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,5-hexanediol, 2,4-heptanediol, 2-ethyl-1,3-Hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, glycerin, n-nonyl acetate, monohexyl ether, ethylene glycol mono-2-ethylhexyl ether, ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, diethylene glycol monoethyl ether, diethylene glycol monoisopropyl ether, diethylene glycol mono-n-butyl ether, diethylene glycol monoisobutyl ether, diethylene glycol monohexyl ether, diethylene glycol monophenyl ether, diethylene glycol monobenzyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol monomethyl ether, triethylene glycol-n-butyl ether, triethylene glycol butyl methyl ether, tetraethylene glycol dimethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-n-butyl ether, tripropylene glycol dimethyl ether, tripropylene glycol monomethyl ether, tripropylene glycol mono-n-propyl ether, tripropylene glycol mono-n-butyl ether, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, triacetin, propylene glycol diacetate, dipropylene glycol methyl-n-propyl ether, dipropylene glycol methyl ether acetate, 1,4-butanediol diacetate, 1,3-butylene glycol diacetate, 1,Examples of the diethyl ester include 6-hexanediol diacetate, triethylene glycol diacetate, γ-butyrolactone, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, dihexyl malonate, diethyl succinate, dipropyl succinate, dibutyl succinate, dihexyl succinate, dimethyl adipate, diethyl adipate, and dibutyl adipate. These may be used alone or in combination.

[0114] The high boiling point solvent may be appropriately selected from the above-mentioned solvents according to the temperature at which the metal-containing film-forming composition of the present invention is heat-treated. The boiling point of the high boiling point solvent is preferably 180°C to 300°C, more preferably 200°C to 300°C. With such a boiling point, there is no risk of the solvent volatilizing too quickly during baking (heat treatment), so that sufficient thermal fluidity can be obtained during film formation, and it is believed that a resist underlayer film having excellent filling / flattening properties can be formed. In addition, with such a boiling point, the solvent does not volatilize and remains in the film even after baking, so there is no risk of adversely affecting the film properties such as etching resistance.

[0115] The amount of the organic solvent to be added is preferably in the range of 200 to 10,000 parts, more preferably 250 to 5,000 parts, based on 100 parts by mass of the (a) compound for forming a metal-containing film.

[0116] When a high boiling point solvent is used, the blending amount is preferably 1 to 30 parts by mass per 100 parts by mass of an organic solvent having a boiling point of less than 180° C. Such a blending amount is preferable because it can impart sufficient thermal fluidity during baking and does not remain in the film, leading to deterioration of film properties such as etching resistance.

[0117] <Composition for forming resist underlayer film> The composition is a composition for forming a metal-containing film that can be used as a resist underlayer film in a multi-layer resist method, and can further contain one or more of (c) a crosslinking agent, (d) a surfactant, (e) a flowability promoter, and (f) an acid generator. Hereinafter, components contained in the composition for forming a metal-containing film (composition for forming a resist underlayer film) of the present invention other than the (a) compound for forming a metal-containing film and (b) organic solvent will be described.

[0118] [(c) Crosslinking agent] The resist underlayer film forming composition of the present invention may further contain (c) a crosslinking agent in order to increase the denseness of the film and further suppress intermixing with the resist upper layer film. The crosslinking agent is not particularly limited, and various known crosslinking agents can be widely used. Examples include melamine-based crosslinking agents, acrylate-based crosslinking agents, glycoluril-based crosslinking agents, benzoguanamine-based crosslinking agents, urea-based crosslinking agents, β-hydroxyalkylamide-based crosslinking agents, isocyanurate-based crosslinking agents, aziridine-based crosslinking agents, oxazoline-based crosslinking agents, phenol-based crosslinking agents (e.g., methylol or alkoxymethyl-type crosslinking agents of polynuclear phenols), epoxy-based crosslinking agents, and oxetane-based crosslinking agents. The content of the (c) crosslinking agent is preferably 5 to 50 parts by mass, more preferably 10 to 40 parts by mass, based on 100 parts by mass of the (a) metal-containing film forming compound.

[0119] Specific examples of the melamine-based crosslinking agent include hexamethoxymethylated melamine, hexabutoxymethylated melamine, alkoxy- and / or hydroxy-substituted products thereof, and partial self-condensates thereof. A specific example of the acrylate crosslinking agent is dipentaerythritol hexaacrylate. Specific examples of glycoluril crosslinking agents include tetramethoxymethylated glycoluril, tetrabutoxymethylated glycoluril, alkoxy and / or hydroxy substituted products thereof, and partial self-condensates thereof. Specific examples of benzoguanamine-based crosslinking agents include tetramethoxymethylated benzoguanamine, tetrabutoxymethylated benzoguanamine, alkoxy- and / or hydroxy-substituted products thereof, and partial self-condensates thereof. Specific examples of the urea-based crosslinking agent include dimethoxymethylated dimethoxyethyleneurea, its alkoxy and / or hydroxyl substituted derivatives, and partial self-condensates thereof. A specific example of the β-hydroxyalkylamide crosslinking agent is N,N,N',N'-tetra(2-hydroxyethyl)adipamide. Specific examples of the isocyanurate crosslinking agent include triglycidyl isocyanurate and triallyl isocyanurate. Specific examples of the aziridine crosslinking agent include 4,4'-bis(ethyleneiminocarbonylamino)diphenylmethane and 2,2-bishydroxymethylbutanol-tris[3-(1-aziridinyl)propionate]. Specific examples of the oxazoline crosslinking agent include 2,2'-isopropylidenebis(4-benzyl-2-oxazoline), 2,2'-isopropylidenebis(4-phenyl-2-oxazoline), 2,2'-isopropylidenebis(4-phenyl-2-oxazoline), 2,2'-methylenebis-4,5-diphenyl-2-oxazoline, 2,2'-methylenebis-4-phenyl-2-oxazoline, 2,2'-methylenebis-4-tertbutyl-2-oxazoline, 2,2'-bis(2-oxazoline), 1,3-phenylenebis(2-oxazoline), 1,4-phenylenebis(2-oxazoline), and 2-isopropenyloxazoline copolymer.

[0120] Specific examples of polynuclear phenol-based crosslinking agents include compounds represented by the following general formula (XL-1). [ka] (In the formula, S is a single bond or a hydrocarbon group having 1 to 20 carbon atoms and a valence of s. R6 is a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. s is an integer of 1 to 5.)

[0121] S is a single bond or a hydrocarbon group having 1 to 20 carbon atoms and a valence of s. s is an integer of 1 to 5, and is more preferably 2 or 3. Specific examples of S include groups obtained by removing s hydrogen atoms from methane, ethane, propane, butane, isobutane, pentane, cyclopentane, hexane, cyclohexane, methylpentane, methylcyclohexane, dimethylcyclohexane, trimethylcyclohexane, benzene, toluene, xylene, ethylbenzene, ethylisopropylbenzene, diisopropylbenzene, methylnaphthalene, ethylnaphthalene, and eicosane. R6 is a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. Specific examples of the alkyl group having 1 to 20 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a pentyl group, an isopentyl group, a hexyl group, an octyl group, an ethylhexyl group, a decyl group, and an eicosanyl group, and a hydrogen atom or a methyl group is preferable.

[0122] Specific examples of the compound represented by the above general formula (XL-1) include the following compounds. Among these, from the viewpoint of improving the curability and thickness uniformity of the organic film, hexamethoxymethylated triphenolmethane, triphenolethane, 1,1,1-tris(4-hydroxyphenyl)ethane, and tris(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene are preferred. R6 is the same as above. [ka]

[0123] [ka]

[0124] The epoxy-based crosslinking agent and the oxetane-based crosslinking agent may be of a monomer type or a polymer type. Specific examples of the monomer type include, but are not limited to, those shown below. [ka]

[0125] The above compounds are commercially available, but the epoxy-based crosslinking agent and the oxetane-based crosslinking agent can also be obtained by reacting a hydroxyl group with epibromohydrin, 3-bromomethyloxetane, or the like, as shown in the following formula. In the following formula, R is 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 alkyl group having 7 to 31 carbon atoms. All the hydroxyl groups can be left unreacted. In this case, it is preferable that the number of epoxy + oxetane is greater than the number of hydroxyl groups, and more preferably, the number of epoxy + oxetane is greater than the number of hydroxyl groups*2. The content of these compounds is preferably 5 to 50 parts by mass, more preferably 10 to 40 parts by mass, relative to 100 parts by mass of the (a) metal-containing film-forming compound. [ka]

[0126] Specific examples of compounds having a hydroxyl group that can be used in the above reaction include, but are not limited to, the following: [ka]

[0127] As the polymer type, specifically, there can be mentioned polymers in which the molar fraction of the repeating units represented by the following general formulae (XL-2) and (XL-3) is 20% or more. When the molar fraction of the structural units represented by the general formulae (XL-2) and (XL-3) does not total 100%, other structural units include α,β-unsaturated carboxylic acid esters such as other acrylic acid esters, other methacrylic acid esters, other acrylic acid amides, other methacrylic acid amides, crotonates, maleates, and itaconic acid esters; α,β-unsaturated carboxylic acids such as methacrylic acid, acrylic acid, maleic acid, and itaconic acid; acrylonitrile; methacrylonitrile; α,β-unsaturated lactones such as 5,5-dimethyl-3-methylene-2-oxotetrahydrofuran; norbornene derivatives, tetracyclo[4.4.0.1 2,5 .1 7,10 Any structural unit derived from cyclic olefins such as dodecene derivatives; α,β-unsaturated carboxylic anhydrides such as maleic anhydride and itaconic anhydride; allyl ethers; vinyl ethers; vinyl esters; and vinyl silanes can be used in combination. These polymers preferably have a weight average molecular weight of 1,000 to 20,000 and a GPC dispersion degree of 2.0 or less. The content of these compounds is preferably 5 to 50 parts by mass, more preferably 10 to 40 parts by mass, relative to 100 parts by mass of the (A) compound for forming a metal-containing film. [ka] (In the formula, R7 is a hydrogen atom or a methyl group, R8 is a hydrogen atom or a group selected from the following formulae (2-1) to (2-3), and L1 is a divalent organic group containing a single bond, -C(=O)O-, -C(=O)NH-, or -C(=O)NCH3-.)

[0128] In the above general formula (XL-2), from the viewpoint of curability, it is preferable that the number of groups (2-1) to (2-3) in R8 is greater than the number of hydrogen atoms, and more preferably the number of groups (2-1) to (2-3) is greater than the number of hydrogen atoms*2. [ka] (In the formula, R7 is a hydrogen atom or a methyl group, and R9 is a group selected from the following formulae (2-1) to (2-3).) [ka] (In the above formula, the dashed lines represent bonds.)

[0129] <(d) Surfactant> To the resist underlayer film forming composition of the present invention, a surfactant (d) can be added to improve the coating property in spin coating. For example, the surfactants described in

[0142] to

[0147] of JP-A-2009-269953 can be used. When the surfactant is added, the amount of the surfactant is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, based on 100 parts by mass of the above-mentioned (a) compound for forming a metal-containing film.

[0130] <(e) Flow enhancers> The resist underlayer film forming composition of the present invention can also be blended with other compounds or polymers. The flow promoter is mixed with the metal-containing film forming compound of the present invention to improve the film forming properties of spin coating and the embedding properties of a substrate having a step. The flow promoter is preferably a material having a high carbon atom density and high etching resistance.

[0131] Such materials include phenol, o-cresol, m-cresol, p-cresol, 2,3-dimethylphenol, 2,5-dimethylphenol, 3,4-dimethylphenol, 3,5-dimethylphenol, 2,4-dimethylphenol, 2,6-dimethylphenol, 2,3,5-trimethylphenol, 3,4,5-trimethylphenol, 2-tert-butylphenol, 3-tert-butylphenol, 4-tert-butylphenol, 2-phenylphenol, 3-phenylphenol, 4-phenylphenol, 3,5- Diphenylphenol, 2-naphthylphenol, 3-naphthylphenol, 4-naphthylphenol, 4-tritylphenol, resorcinol, 2-methylresorcinol, 4-methylresorcinol, 5-methylresorcinol, catechol, 4-tert-butylcatechol, 2-methoxyphenol, 3-methoxyphenol, 2-propylphenol, 3-propylphenol, 4-propylphenol, 2-isopropylphenol, 3-isopropylphenol, 4-isopropylphenol, 2-methoxy-5-methylphenol, 2-tert-Butyl-5-methylphenol, pyrogallol, thymol, isothymol, 4,4'-(9H-fluoren-9-ylidene)bisphenol, 2,2'dimethyl-4,4'-(9H-fluoren-9-ylidene)bisphenol, 2,2'diallyl-4,4'-(9H-fluoren-9-ylidene)bisphenol, 2,2'difluoro-4,4'-(9H-fluoren-9-ylidene)bisphenol, 2,2'diphenyl-4,4'-(9H-fluoren-9-ylidene)bisphenol, 2,2'dimethoxy-4,4'-(9H- fluoren-9-ylidene) bisphenol, 2,3,2',3'-tetrahydro-(1,1')-spirobiindene-6,6'-diol, 3,3,3',3'-tetramethyl-2,3,2',3'-tetrahydro-(1,1')-spirobiindene-6,6'-diol, 3,3,3',3',4,4'-hexamethyl-2,3,2',3'-tetrahydro-(1,1')-spirobiindene-6,6'-diol, 2,3,2',3'-tetrahydro-(1,1')-spirobiindene-5,5'-diol, 5,5'-dimethyl-3,3,3',3'-tetramethyl-2,3,2',3'-tetrahydro-(1,1')-spirobiindene-6,6'-diol, 1-naphthol, 2-naphthol, 2-methyl-1-naphthol, 4-methoxy-1-naphthol, 7-methoxy-2-naphthol, dihydroxynaphthalenes such as 1,5-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, and 2,6-dihydroxynaphthalene, 3-hydroxynaphthalene-2-methyl carboxylate, indene, hydroxyindene, benzofuran, hydroxyanthracene, acenaphthylene, and biphenyl. Examples of the novolak resins include bisphenol, trisphenol, dicyclopentadiene, tetrahydroindene, 4-vinylcyclohexene, norbornadiene, 5-vinylnorborn-2-ene, α-pinene, β-pinene, and limonene; polyhydroxystyrene, polystyrene, polyvinylnaphthalene, polyvinylanthracene, polyvinylcarbazole, polyindene, polyacenaphthylene, polynorbornene, polycyclodecene, polytetracyclododecene, polynortricyclene, poly(meth)acrylate, and copolymers thereof. In addition, naphthol dicyclopentadiene copolymers described in JP 2004-205685 A, fluorene bisphenol novolac resins described in JP 2005-128509 A, acenaphthylene copolymers described in JP 2005-250434 A, fullerenes having phenol groups described in JP 2006-227391 A, bisphenol compounds and novolac resins described in JP 2006-293298 A, novolac resins of adamantanephenol compounds described in JP 2006-285095 A, bisnaphthol compounds and novolac resins described in JP 2010-122656 A, fluorene compounds described in JP 2017-119671 A, and fullerene resin compounds described in JP 2008-158002 A can also be blended. The blending amount of the flow promoter is preferably 0.001 to 100 parts by mass, more preferably 0.01 to 50 parts by mass, based on 100 parts by mass of the compound for forming a metal-containing film of the present invention.

[0132] In addition, in the composition for forming a resist underlayer film of the present invention, as an additive for imparting filling / flattening properties, for example, a liquid additive having a polyethylene glycol or polypropylene glycol structure, or a thermally decomposable polymer having a weight loss rate of 40% by mass or more between 30° C. and 250° C. and a weight average molecular weight of 300 to 200,000 is preferably used. This thermally decomposable polymer preferably contains a repeating unit having an acetal structure represented by the following general formula (DP1) or (DP1a).

[0133] [ka] (In the formula, R 10 is a hydrogen atom or an optionally substituted saturated or unsaturated monovalent organic group having 1 to 30 carbon atoms. Y is a saturated or unsaturated divalent organic group having 2 to 30 carbon atoms.

[0134] [ka] (In the formula, R 10a is an alkyl group having 1 to 4 carbon atoms. a is a saturated or unsaturated divalent hydrocarbon group having 4 to 10 carbon atoms, which may have an ether bond; and n represents the average number of repeating units and is 3 to 500.

[0135] <(f) Acid generator> The resist underlayer film forming composition of the present invention may contain (f) an acid generator to further promote the elimination reaction. The acid generator (f) may be one that generates an acid by thermal decomposition or one that generates an acid by light irradiation, and any of these may be added. Specifically, the materials described in paragraphs

[0061] to

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

[0136] The acid generators can be used alone or in combination of two or more. When an acid generator is added, the amount of the acid generator is preferably 0.05 to 50 parts by mass, more preferably 0.1 to 10 parts by mass, based on 100 parts by mass of the (a) compound for forming a metal-containing film.

[0137] <Method for forming resist underlayer film> The present invention provides a method for forming a filling film that functions as a resist underlayer film of a multi-layer resist film used in lithography or a planarizing film for semiconductor manufacturing, using the above-mentioned composition for forming a metal-containing film.

[0138] In the method for forming a resist underlayer film using the composition for forming a metal-containing film of the present invention, the composition for forming a metal-containing film is coated on a substrate to be processed by spin coating or the like. By using the spin coating or the like, good embedding properties can be obtained. After spin coating, the solvent is evaporated, and baking (heat treatment) is performed to promote a crosslinking reaction in order to prevent mixing with the resist upper layer film or the resist intermediate film. The baking is preferably performed at 100°C or higher and 600°C or lower for 10 to 600 seconds, more preferably at 200°C or higher and 500°C or lower for 10 to 300 seconds. Considering the influence on device damage and wafer deformation, the upper limit of the heating temperature in the wafer process of lithography is preferably 600°C or lower, more preferably 500°C or lower.

[0139] In addition, in a method for forming a resist underlayer film using the composition for forming a metal-containing film of the present invention, the composition for forming a metal-containing film of the present invention can be coated on a substrate to be processed by a spin coating method or the like as described above, and the composition for forming a metal-containing film can be baked and cured in an atmosphere having an oxygen concentration of 0.1 vol.% or more and 21 vol.% or less to form a metal-containing film.

[0140] By baking the metal-containing film-forming composition of the present invention in such an oxygen atmosphere, a sufficiently cured film can be obtained. Although the atmosphere during baking may be air, it is preferable to seal in an inert gas such as N2, Ar, or He to reduce oxygen in order to prevent oxidation of the metal-containing film. In order to prevent oxidation, it is necessary to control the oxygen concentration, which is preferably 1000 ppm or less, more preferably 100 ppm or less (volume basis). Preventing oxidation of the metal-containing film during baking is preferable because it does not increase absorption or reduce etching resistance.

[0141] <Pattern Forming Method Using Composition for Forming Resist Underlayer Film> The present invention also provides a pattern formation method by a two-layer resist process using the above-mentioned metal-containing film-forming composition, which comprises forming a metal-containing film on a substrate to be processed using the above-mentioned metal-containing film-forming composition, forming a resist upper layer film on the metal-containing film using a photoresist material, exposing the resist upper layer film to light and then developing the resist upper layer film with a developer to form a pattern in the resist upper layer film, transferring the pattern to the metal-containing film by dry etching using the resist upper layer film with the pattern formed as a mask, and processing the substrate to be processed using the metal-containing film with the pattern formed as a mask to form a pattern on the substrate to be processed.

[0142] Since the resist top layer film in the two-layer resist process exhibits etching resistance to chlorine-based gases, it is preferable that the dry etching of the metal-containing film in the two-layer resist process is performed using the resist top layer film as a mask with an etching gas mainly containing a chlorine-based gas.

[0143] In addition, the present invention provides a pattern formation method by a three-layer resist process using such a metal-containing film-forming composition, which includes forming a metal-containing film on a substrate to be processed using the above-mentioned metal-containing film-forming composition, forming a silicon-containing resist intermediate film on the metal-containing film using a silicon-containing resist intermediate film material, forming a resist upper layer film on the resist intermediate film using a photoresist material, exposing the resist upper layer film to a pattern, and developing the resist upper layer film with a developer to form a pattern on the resist upper layer film. Using the resist upper layer film with the pattern formed as a mask, transfer the pattern to the resist intermediate film by dry etching. Using the resist intermediate film with the pattern transferred as a mask, transfer the pattern to the metal-containing film by dry etching. Using the metal-containing film with the pattern formed as a mask, the substrate to be processed is processed. A pattern formation method is provided, which is characterized by the above-mentioned.

[0144] An example of a three-layer resist process is specifically shown below with reference to Figure 1. In the case of the three-layer resist process, as shown in Figure 1(A), a metal-containing film (metal-containing resist underlayer film) 3 is formed on a processable layer 2 laminated on a processable substrate 1 using the metal-containing film-forming composition of the present invention, and then a silicon-containing resist intermediate film 4 is formed, and a resist upper layer film 5 is formed thereon.

[0145] Next, as shown in FIG. 1(B), a desired portion (exposed portion) 6 of the resist upper layer film 5 is exposed, and PEB and development are performed to form a resist upper layer film pattern 5a (FIG. 1(C)). Using the obtained resist upper layer film pattern 5a as a mask, the silicon-containing resist intermediate film 4 is etched using a CF-based gas to form a silicon-containing resist intermediate film pattern 4a (FIG. 1(D)). After removing the resist upper layer film pattern 5a, the metal-containing film 3 is chlorine plasma etched using the obtained silicon-containing resist intermediate film pattern 4a as a mask to form a metal-containing film pattern (metal-containing resist underlayer film pattern) 3a (FIG. 1(E)). Furthermore, after removing the silicon-containing resist intermediate film pattern 4a, the processed layer 2 is etched using the metal-containing film pattern 3a as a mask to form a pattern 2a in the processed layer (FIG. 1(F)).

[0146] The silicon-containing resist intermediate film in the above three-layer resist process exhibits etching resistance to chlorine-based gas and hydrogen-based gas, so in the above three-layer resist process, the dry etching of the metal-containing film using the silicon-containing resist intermediate film as a mask is preferably performed using an etching gas mainly composed of a chlorine-based gas or a hydrogen-based gas.

[0147] As the silicon-containing resist intermediate film in the above three-layer resist process, a polysiloxane-based intermediate film is also preferably used. By imparting an anti-reflection effect to the silicon-containing resist intermediate film, reflection can be suppressed. In particular, for 193 nm exposure, if a material containing many aromatic groups and having high etching selectivity with the substrate is used as the organic film, the k value becomes high and the substrate reflection becomes high, but by imparting absorption to the silicon-containing resist intermediate film to obtain an appropriate k value, it becomes possible to suppress reflection, and the substrate reflection can be reduced to 0.5% or less. As the silicon-containing resist intermediate film having an anti-reflection effect, anthracene is preferably used for 248 nm and 157 nm exposure, and polysiloxane with a pendant light-absorbing group having a phenyl group or a silicon-silicon bond and crosslinked by acid or heat is preferably used for 193 nm exposure.

[0148] In addition, the present invention provides a pattern formation method by a four-layer resist process using such a metal-containing film-forming composition, which includes forming a metal-containing film on a substrate to be processed using the above-mentioned metal-containing film-forming composition, forming a silicon-containing resist intermediate film on the resist underlayer film using a silicon-containing resist intermediate film material, forming an organic antireflective coating (BARC) or an adhesion film on the silicon-containing resist intermediate film, forming a resist upper layer film on the BARC using a photoresist material, exposing the resist upper layer film to a pattern, and developing the resist upper layer film with a developer to form a pattern on the resist upper layer film. Using the resist upper layer film on which the pattern has been formed as a mask, a pattern is transferred to the BARC or adhesion film and the silicon-containing resist intermediate film by dry etching. Using the silicon-containing resist intermediate film on which the pattern has been transferred as a mask, a pattern is transferred to the metal-containing film by dry etching. The pattern formation method is characterized by having the steps of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed.

[0149] Alternatively, an inorganic hard mask may be formed instead of the silicon-containing resist underlayer film. In this case, at least a metal-containing film is formed on a workpiece using the metal-containing film-forming composition of the present invention, an inorganic hard mask selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film is formed on the metal-containing film, a resist upper layer film is formed on the inorganic hard mask using a photoresist composition to form a circuit pattern on the resist upper layer film, the inorganic hard mask is etched using the resist upper layer film on which the pattern has been formed as a mask, the metal-containing film is etched using the inorganic hard mask on which the pattern has been formed as a mask, and the workpiece is etched using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the workpiece, thereby forming a semiconductor device circuit pattern on the substrate.

[0150] As described above, when an inorganic hard mask 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, methods for forming a silicon nitride film are described in JP-A-2002-334869 and WO-A-2004 / 066377. The thickness of the inorganic hard mask is preferably 5 to 200 nm, more preferably 10 to 100 nm. In addition, a SiON film, which has a high effect as an anti-reflective film, is most preferably used as the inorganic hard mask. Since the substrate temperature when forming the SiON film is 300 to 500° C., the metal-containing film needs to 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 to 500° C., so that it is possible to combine an inorganic hard mask formed by a CVD method or an ALD method with a metal-containing film formed by a spin coating method.

[0151] As described above, a photoresist film may be formed on the inorganic hard mask as a resist top layer, but an organic anti-reflective coating (BARC) or adhesion film may be formed on the inorganic hard mask by spin coating, and a photoresist film may be formed on top of that. In particular, when a SiON film is used as the inorganic hard mask, the two-layer anti-reflective coating 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 advantage of forming the BARC is that it has the effect of reducing the tailing of the photoresist pattern directly above the SiON film.

[0152] In addition, in the present invention, as a pattern formation method by a multilayer resist process using such a metal-containing film-forming composition, a resist underlayer film is formed on a substrate to be processed, the metal-containing film-forming composition of the present invention is applied onto the resist underlayer film, and then a metal-containing film is formed by heat treatment. A resist upper layer film is formed on the metal-containing film using a photoresist material, the resist upper layer film is pattern-exposed and then developed with a developer to form a pattern in the resist upper layer film, and the resist upper layer film on which the pattern has been formed is used as a mask to transfer the pattern to the metal-containing film by dry etching. Using the metal-containing film on which the pattern has been transferred as a mask, a pattern is transferred to the resist underlayer film by dry etching. Furthermore, the resist underlayer film on which the pattern has been formed is used as a mask to process the substrate to form a pattern on the substrate to be processed. Thus, a semiconductor device circuit pattern can be formed on the substrate.

[0153] As described above, a photoresist film may be formed on the metal-containing film as a resist upper layer film, but an organic adhesive film may be formed on the metal-containing film by spin coating, and a photoresist film may be formed thereon.

[0154] As described above, when forming a resist underlayer film on a substrate to be processed, the resist underlayer film can be formed by a method using a coating type organic underlayer film material, a CVD method, an ALD method, etc. Coating type organic underlayer film materials are disclosed in JP2012-001687A, JP2012-077295A, JP2004-264710A, JP2005-043471A, JP2005-250434A, JP2007-293294A, JP2008-065303A, and the like. No. 2004-205685, No. 2007-171895, No. 2009-014816, No. 2007-199653, No. 2008-274250, No. 2010-122656, No. 2012-214720, No. 2014-0 Examples of resins and compositions disclosed in JP-A-2005-128509, JP-A-2006-259249, JP-A-2006-259482, JP-A-2006-293298, JP-A-2007-316282, JP-A-2012-145897, JP-A-2017-119671, JP-A-2019-044022, and the like can be mentioned.

[0155] The resist upper layer film in the above multi-layer resist process may be either positive or negative, and may be the same as a commonly used photoresist composition. After spin-coating the photoresist composition, pre-baking is performed, preferably at 60 to 180°C for 10 to 300 seconds. Thereafter, exposure is performed according to a conventional method, followed by post-exposure baking (PEB) and development to obtain a resist pattern. The thickness of the resist upper layer film is not particularly limited, but is preferably 30 to 500 nm, and more preferably 50 to 400 nm.

[0156] Examples of the exposure light include high energy rays with a wavelength of 300 nm or less, specifically, excimer lasers with wavelengths of 248 nm, 193 nm, and 157 nm, soft X-rays with wavelengths of 3 to 20 nm, electron beams, and X-rays.

[0157] The method for forming the pattern on the resist upper layer film is preferably photolithography with a wavelength of 5 nm or more and 300 nm or less, direct drawing with an electron beam, nanoimprinting, or a combination of these.

[0158] In the pattern forming method, the development method is preferably alkaline development or development using an organic solvent.

[0159] Next, etching is performed using the obtained resist pattern as a mask. In the three-layer resist process, etching of the silicon-containing resist intermediate film and the inorganic hard mask is performed using a fluorocarbon-based gas as a mask for the upper resist pattern. This forms a silicon-containing resist intermediate film pattern and an inorganic hard mask pattern.

[0160] Next, the metal-containing film is etched using the silicon-containing resist intermediate film pattern or the inorganic hard mask pattern as a mask. The etching of the metal-containing film is preferably performed using an etching gas mainly containing a chlorine-based gas.

[0161] The next etching of the workpiece can also be done by a normal method, for example, if the workpiece is SiO2, SiN, or a silica-based low dielectric constant insulating film, etching is done mainly with fluorocarbon gases. When etching the substrate with fluorocarbon gases, the silicon-containing resist intermediate film pattern in the three-layer resist process is peeled off at the same time as the substrate is processed.

[0162] The metal-containing film obtained by using the metal-containing film-forming composition of the present invention is characterized by excellent etching resistance when etching the workpiece.

[0163] The workpiece (substrate) is not particularly limited, and may be a substrate such as Si, α-Si, p-Si, SiO2, SiN, SiON, W, TiN, or Al, or a substrate on which a workpiece layer is formed. As the workpiece layer, various low-k films such as Si, SiO2, SiON, SiN, p-Si, α-Si, W, W-Si, Al, Cu, or Al-Si and their stopper films are used, and may be formed to a thickness of usually 50 to 10,000 nm, particularly 100 to 5,000 nm. When forming a workpiece layer, the substrate and the workpiece layer are made of different materials.

[0164] In the pattern forming method using the metal-containing film forming composition of the present invention, it is preferable to use a substrate to be processed having a structure or step having a height of 30 nm or more. As described above, since the metal-containing film forming composition of the present invention has excellent filling / flattening properties, even if the substrate to be processed has a structure or step (unevenness) having a height of 30 nm or more, a flat cured film can be formed. The height of the structure or step of the substrate to be processed is preferably 30 nm or more, more preferably 50 nm or more, and more preferably 100 nm or more. In the method for processing a stepped substrate having a pattern of the above height, the metal-containing film forming composition of the present invention is formed into a film and filled / flattened, thereby making it possible to uniformize the film thickness of the resist intermediate film and resist top layer film to be formed thereafter, which is very preferable, since it is easy to ensure the exposure depth margin (DOF) during photolithography.

[0165] <Method of forming a tone-reversal pattern using a composition for forming a metal-containing film> Further, in the present invention, a tone-reversal pattern formation method using such a metal-containing film-forming composition includes forming a resist underlayer film on a substrate to be processed, forming a 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 oxynitride film and an organic thin film on the resist underlayer film, forming a resist upper layer film using a photoresist material on the resist intermediate film or the combination of the inorganic hard mask intermediate film and the organic thin film, exposing the resist upper layer film to a pattern and developing it with a developer to form a pattern on the resist upper layer film, transferring the pattern to the resist intermediate film, or the organic thin film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film on which the pattern has been formed as a mask, and then performing dry etching on the resist intermediate film or the inorganic hard mask intermediate film on which the pattern has been transferred by using the resist intermediate film or the inorganic hard mask intermediate film as a mask. a metal-containing film covering the resist underlayer film on which the pattern has been formed, using the metal-containing film-forming composition to form a metal-containing film, filling spaces between the resist underlayer film patterns with the metal-containing film, etching back the metal-containing film covering the resist underlayer film on which the pattern has been formed by using a chemical stripper or dry etching to expose an upper surface of the resist underlayer film on which the pattern has been formed, removing the resist intermediate film or hard mask intermediate film remaining on the upper surface of the resist underlayer film by dry etching, removing the resist underlayer film on which the pattern has been formed and its surface exposed by dry etching, forming a reverse pattern of the original pattern on the metal-containing film, and processing the workpiece substrate using the metal-containing film on which the reverse pattern has been formed as a mask to form a reverse pattern on the workpiece substrate.

[0166] An example of the formation of a tone reversal pattern is specifically shown below with reference to Fig. 2. As shown in Fig. 2(G), a resist underlayer film 7 made of a coating type organic underlayer film material is formed on a processable layer 2 laminated on a processable substrate 1, and then a silicon-containing resist intermediate film 4 is formed, and a resist upper layer film 5 is formed thereon.

[0167] Next, as shown in Fig. 2(H), a desired portion (exposed portion) 6 of the resist upper layer film 5 is exposed, and PEB and development are performed to form a resist upper layer film pattern 5a (Fig. 2(I)). Using the obtained resist upper layer film pattern 5a as a mask, the silicon-containing resist intermediate film 4 is etched using a CF-based gas to form a silicon-containing resist intermediate film pattern 4a (Fig. 2(J)). After removing the resist upper layer film pattern 5a, the resist underlayer film 7 made of a coating type organic underlayer film material is oxygen plasma etched using the obtained silicon-containing resist intermediate film pattern 4a as a mask to form a resist underlayer film pattern 7a made of a coating type organic underlayer film material (Fig. 2(K)).

[0168] The metal-containing film-forming composition of the present invention is applied onto the resist underlayer film pattern 7a made of a coating type organic underlayer film material, and then heat-treated to cover the metal-containing film 8, and the metal-containing film fills the gaps between the resist underlayer film patterns 7a made of the coating type organic underlayer film material (FIG. 2(L)). Next, the metal-containing film 8 covering the resist underlayer film pattern 7a made of the coating type organic underlayer film material is etched back by a chemical stripper or dry etching to expose the upper surface of the resist underlayer film pattern 7a made of the coating type organic underlayer film material (FIG. 2(M)). Furthermore, the silicon-containing resist intermediate film pattern 4a remaining on the upper surface of the resist underlayer film pattern 7a made of the coating type organic underlayer film material is removed by dry etching (FIG. 2(N)). Next, the resist underlayer film pattern 7a made of the coating-type organic underlayer film material is removed by dry etching, and an inverted pattern of the original pattern is formed on the metal-containing film (a metal-containing film pattern 8a which is an inverted version of the resist underlayer film pattern) (FIG. 2(O)). After that, the workpiece substrate is processed using the metal-containing film pattern 8a which is an inverted version of the resist underlayer film pattern as a mask to form a tone-reversed pattern on the workpiece substrate (FIG. 2(P)).

[0169] As described above, when forming a resist underlayer film on a substrate to be processed, the resist underlayer film can be formed by a method using a coating type organic underlayer film material, a CVD method, an ALD method, etc. Coating type organic underlayer film materials are disclosed in JP2012-1687A, JP2012-77295A, JP2004-264710A, JP2005-043471A, JP2005-250434A, JP2007-293294A, JP2008-65303A, JP2009-100111A, and JP2006-2009-2010. JP 2004-205685 A, JP 2007-171895 A, JP 2009-14816 A, JP 2007-199653 A, JP 2008-274250 A, JP 2010-122656 A, JP 2012-214720 A, JP 2014-29435 A, Examples of the resins and compositions disclosed in International Publication WO2012 / 077640, International Publication WO2010 / 147155, International Publication WO2012 / 077640, International Publication WO2010 / 147155, International Publication WO2012 / 176767, JP 2005-128509 A, JP 2006-259249 A, JP 2006-259482 A, JP 2006-293298 A, JP 2007-316282 A, JP 2012-145897 A, JP 2017-119671 A, JP 2019-44022 A, and the like can be mentioned.

[0170] In the above-mentioned tone reversal pattern forming method, it is preferable to coat the obtained resist underlayer film pattern with a metal-containing film forming composition, and then remove the metal-containing film using a dry etching gas mainly composed of a chlorine-based gas to expose the upper surface of the resist underlayer film pattern. Then, the resist intermediate film or hard mask intermediate film remaining on the resist underlayer film is removed by dry etching with a fluorocarbon-based gas, and the resist underlayer film pattern with the exposed surface is removed by dry etching with an oxygen-based gas to form a metal-containing film pattern.

[0171] In the tone reversal patterning method, the resist underlayer film pattern preferably has a structure or step having a height of 30 nm or more. As described above, the metal-containing film-forming composition of the present invention has excellent filling / flattening properties, so that even if the processed film has a structure or step (unevenness) having a height of 30 nm or more, a flat cured film can be formed. The height of the structure or step of the resist underlayer film pattern is preferably 30 nm or more, more preferably 50 nm or more, and more preferably 100 nm or more. In the method for reversing a resist underlayer film pattern having a pattern of the above height, the metal-containing film-forming composition of the present invention is formed into a film and filled / flattened, so that the reversal / transfer of the pattern can be performed with high accuracy, which is very preferable. Compared to the resist underlayer film using a conventional coating-type organic underlayer film material, the composition has excellent resistance to dry etching using a fluorocarbon-based gas, so that the resist underlayer film pattern can be reversed with the metal-containing film-forming composition to form a desired resist pattern on the processed film with high accuracy. EXAMPLES

[0172] The present invention will be described in more detail below with reference to Synthesis Examples, Comparative Synthesis Examples, Examples, and Comparative Examples, but the present invention is not limited thereto. Note that, as for the molecular weight and dispersity, the weight average molecular weight (Mw) and number average molecular weight (Mn) in terms of polystyrene were determined by gel permeation chromatography (GPC) using tetrahydrofuran as an eluent, and the dispersity (Mw / Mn) was determined.

[0173] [Synthesis example] In the following synthesis examples and comparative examples, the following tin compounds Sn: (Sn-1) to (Sn-3), raw material group W: (W1) to (W10), and raw material group G: (G-1) to (G-12) were used. Each raw material group is shown below.

[0174] Tin compounds (Sn): [ka]

[0175] Raw material group W: [ka]

[0176] Raw material group G: [ka]

[0177] [Synthesis Example 1] Synthesis of metal-containing film-forming compound (A-1) 5.0 g of tin compound (Sn-1), 4.6 g of raw material (W1) and 100 g of toluene were added and reacted for 7 hours at 100° C. while removing tert-butyl alcohol. After the reaction, the solvent was removed under reduced pressure to obtain compound (A-1). (A-1): Mw = 322, Mw / Mn = 1.05

[0178] [Synthesis Example 2] Synthesis of metal-containing film-forming compound (A-2) 5.0 g of tin compound (Sn-3), 6.0 g of raw material (W2), and 100 g of toluene were added and reacted for 7 hours at 100° C. After the reaction, the solvent was removed under reduced pressure to obtain compound (A-2). (A-2): Mw = 344, Mw / Mn = 1.08

[0179] [Synthesis Example 3] Synthesis of metal-containing film-forming compound (A-3) 5.0 g of tin compound (Sn-2), 6.8 g of raw material (W3) and 100 g of toluene were added and reacted for 7 hours while removing water at 130° C. After the reaction, the solvent was removed under reduced pressure to obtain compound (A-3). (A-3): Mw = 356, Mw / Mn = 1.07

[0180] [Synthesis Example 4] Synthesis of metal-containing film-forming compound (A-4) 5.0 g of tin compound (Sn-3), 6.0 g of raw material (W2), 1.3 g of raw material (G-1) and 100 g of toluene were added and reacted at 100° C. for 7 hours. After the reaction, the solvent was removed under reduced pressure to obtain compound (A-4). (A-4): Mw = 401, Mw / Mn = 1.24

[0181] [Synthesis Examples 5-12] Synthesis of metal-containing film-forming compounds (A-5)-(A-12) (A-5) to (A-12) were obtained under the same reaction conditions as in Synthesis Example 4, except that the raw material W and the raw material group G were used in the amounts shown in Tables 1-1 to 1-2. In addition, - indicates that the corresponding raw material group was not used. The weight average molecular weight (Mw) and dispersity (Mw / Mn) of these compounds were determined. The results are shown in Table 3.

[0182] [Table 1-1]

[0183] [Table 1-2]

[0184] [Comparative Synthesis Example 1] Synthesis of a metal-containing film-forming compound (R-1) for comparison 5.0 g of tin compound (Sn-3) was stirred at room temperature, and 5.0 g of raw material (G-10) was added dropwise. After the addition, the temperature was raised to 80°C and the mixture was stirred for 7 hours. After the reaction was completed, acrylic acid was removed under reduced pressure to obtain (R-1).

[0185] [Comparative Synthesis Example 2] Synthesis of a metal-containing film-forming compound (R-2) for comparison 5.0 g of tin compound (Sn-2), 6.0 g of raw material (G-11), and 100 g of toluene were added and reacted for 7 hours at 130° C. while removing water. After the reaction, the solvent was removed under reduced pressure to obtain (R-2).

[0186] [Comparative Synthesis Example 3] Synthesis of a metal-containing film-forming compound (R-3) for comparison 5.0 g of tin compound (Sn-2), 11.4 g of raw material (G-12), and 100 g of toluene were added and reacted for 7 hours while removing water at 130°C. After the reaction, the solvent was removed under reduced pressure to obtain (R-3).

[0187] Table 2 shows the amounts of materials charged and the compounds synthesized in Comparative Synthesis Examples 1 to 3. The weight average molecular weight (Mw) and dispersity (Mw / Mn) of these compounds were also determined. The results are shown in Table 3.

[0188] [Table 2]

[0189] [Table 3]

[0190] [Synthesis of Comparative Metal-containing Film-forming Compound (R-4)] As a compound having a metal different from the compound for forming a metal-containing film of the present invention, a titanium compound reported in [Synthesis Example A-II] of Japanese Patent No. 6189758 was synthesized. A solution of 27 g of deionized water and 500 g of IPA was dropped into a solution of 284 g of titanium tetraisopropoxide (Tokyo Chemical Industry Co., Ltd.) in 500 g of IPA while stirring at room temperature for 2 hours. 120 g of 2-methyl-2,4-pentanediol was added to the obtained solution and stirred at room temperature for 30 minutes. After concentrating this solution at 30°C under reduced pressure, it was further heated to 60°C and continued to be heated under reduced pressure until no distillate was produced. When no distillate was observed, 1,200 g of PGMEA was added and heated at 40°C under reduced pressure until no IPA was produced, obtaining 1,000 g of a PGMEA solution of titanium-containing compound (R-4) (compound concentration 20% by mass). The molecular weight of this product in terms of polystyrene was measured and found to be Mw=1,100.

[0191] [Synthesis of Comparative Organic Film-Forming Resin (R-5)] In a nitrogen atmosphere, 160.2g of 1,5-dihydroxynaphthalene, 56.8g of formaldehyde, and 300g of PGME (propylene glycol monomethyl ether) were added and homogenized at an internal temperature of 100℃. Then, a mixture of 8.0g of paratoluenesulfonic acid monohydrate and 8.0g of PGME, which had been mixed and homogenized in advance, was slowly dropped and reacted at an internal temperature of 80℃ for 8 hours. After the reaction was completed, the mixture was cooled to room temperature, 2,000ml of MIBK was added, and the mixture was washed six times with 500ml of pure water, and the organic layer was dried under reduced pressure. 300g of THF was added to the residue to make a homogenous solution, and then crystallized in 2,000g of hexane. The precipitated crystals were separated by filtration, washed twice with 500g of hexane, and collected. The collected crystals were dried in a vacuum at 70℃ to obtain resin (R-5). The weight average molecular weight (Mw) and dispersity (Mw / Mn) were determined by GPC, and the results were as follows: (R-5): Mw = 3,300, Mw / Mn = 2.54 [ka]

[0192] Examples 1-1 to 1-19, Comparative Examples 1-1 to 1-5 The metal-containing film-forming compositions UDL-1 to -16 used in Examples 1-1 to 1-19 and the metal-containing film-forming compositions (Comparative Examples UDL-1 to -5) used in Comparative Examples 1-1 to 1-4 were prepared as follows.

[0193] [Metal-containing film forming composition UDL-1] The metal-containing film-forming compound (A-1) was dissolved in a mixed solvent of propylene glycol monomethyl ether acetate (PGMEA) and cyclohexanone (CyHO) containing 0.5 mass% of surfactant FC-4430 (manufactured by Sumitomo 3M Limited) in the ratio shown in Table 4, and the solution was filtered through a 0.2 μm membrane filter to prepare a metal-containing film-forming composition (UDL-1).

[0194] [Preparation of metal-containing film-forming compositions (UDL-2 to 16) and comparative metal-containing film-forming compositions (Comparative UDL-1 to 5)] Each chemical solution was prepared in the same manner as UDL-1, except that the type and content of each component were as shown in Table 4. In Table 4, "-" indicates that the corresponding component was not used. The crosslinking agent used was the formula (C-1) below, the high boiling point solvent (D-1) was 1,6-diacetoxyhexane (boiling point 260°C), the flow promoter polymer (F-1) was used, and the thermal acid generator (TAG) was the formula (TAG-1) described below.

[0195] [Crosslinking agent] The crosslinking agent (C-1) used in the metal-containing film-forming composition is shown below. [ka]

[0196] [Example of synthesis of polymer for fluidity promoter] Synthesis of polymer for fluidity promoter (F-1) Under a nitrogen atmosphere, 20.0 g of cresol novolak, 27.6 g of potassium carbonate, and 100 g of DMF were added to obtain a uniform dispersion at an internal temperature of 50°C. 11.9 g of propargyl bromide was slowly added, and the reaction was carried out for 24 hours at an internal temperature of 50°C. 300 ml of methyl isobutyl ketone and 300 g of pure water were added to the reaction solution to dissolve the precipitated salt, and then the separated aqueous layer was removed. The organic layer was further washed six times with 100 g of 3% aqueous nitric acid solution and 100 g of pure water, and the organic layer was dried under reduced pressure to obtain resin (F-1). The weight average molecular weight (Mw) and dispersity (Mw / Mn) were determined by GPC, and the results were as follows: (F-1): Mw = 8,500, Mw / Mn = 3.46 [ka]

[0197] [Thermal acid generator] The thermal acid generator (TAG-1) used in the metal-containing film-forming composition is shown below. [ka]

[0198] [Table 4]

[0199] As shown in Table 4, the metal-containing film-forming compositions of the present invention (Examples 1-1 to 1-12) can be prepared with a PGMEA-containing composition, and it was confirmed that they have excellent solvent solubility compared to Comparative Example UDL-2, which has two styrene carboxylic acids bonded and cannot be prepared with a PGMEA-containing composition. In addition, it was confirmed that UDL-4 to UDL-12, which were prepared by reacting Raw Material Group W and Raw Material Group G, can be prepared with a PGMEA-only composition and have even better solvent solubility. This is thought to be due to the loss of molecular symmetry.

[0200] [Heat resistance evaluation and solvent resistance evaluation] The metal-containing film-forming compositions (UDL-1 to 16, Comparative Examples UDL-1 to 5) prepared above were applied onto silicon substrates, baked at 100° C. for 60 seconds, and the film thickness (a [nm]) was measured. Then, after baking for 60 seconds at each baking temperature shown in Table 5, the film thickness (b [nm]) was measured, and the film thickness difference before and after the additional baking process (residual film ratio: (b / a)×100) was calculated. Furthermore, PGMEA solvent was dispensed on it, left for 30 seconds, spin-dried, and baked at 100°C for 60 seconds to evaporate the PGMEA, and the film thickness (c [nm]) was measured. The difference in film thickness before and after PGMEA treatment (residual film ratio: (c / b) x 100) was calculated. The results are shown in Table 5 below. [Table 5]

[0201] As shown in Table 5, the metal-containing film-forming compositions of the present invention (Examples 1-1 to 1-12) had a film remaining rate ((b / a) x 100) of 55% or more after high-temperature additional baking, and were found to have the high-temperature bake resistance required for resist underlayer films. On the other hand, Comparative Example 1-3, which does not have a catechol-diol structure, had a film remaining rate ((b / a) x 100) of 43% after high-temperature additional baking, and was confirmed to have poor heat resistance. In addition, when Examples 1-17 to 1-19, which were subjected to high-temperature additional baking at 350°C, were compared with Comparative Example 1-4, the film remaining rate was 8%, meaning that almost no film remained, while Examples 1-17 to 1-19 were 35%, 38%, and 39%, respectively, indicating that more than 30% of the film remained, and it was found that the compositions had heat resistance that allowed them to form films even under ultra-high-temperature baking conditions of 350°C. This is believed to be because the compounds of the present invention have organic ligands bonded to tin at two points like chelates. Furthermore, the film that was baked at high temperature had a residual film rate ((c / b) x 100) of 99% or more after PGMEA rinsing, indicating that crosslinking reactions had occurred and sufficient solvent resistance had been achieved. The residual film rate after baking of UDL-15, which contained the crosslinking agent (C-1), increased from 61% to 65% compared to UDL-11, which did not contain the crosslinking agent. This is thought to be the result of efficient crosslinking caused by the crosslinking agent and suppression of sublimates. In addition, when comparing UDL-4 and UDL-13, which contained the thermal acid generator (G-1), the residual film rate ((c / b) x 100) of UDL-4 after PGMEA rinsing after baking at 250°C was 99.7%, while the residual film rate ((c / b) x 100) of UDL-13 after baking at 200°C and PGMEA rinsing was 100%, resulting in increased curability. This is believed to be the result of the addition of a thermal acid generator, which caused the elimination of leaving groups and the resulting crosslinking reaction to occur efficiently. On the other hand, for comparative examples UDL-1 and UDL-2, the remaining film rate ((b / a) x 100) after high-temperature additional baking was 5% or less. This is believed to be the result of the molecules decomposing and sublimating before the crosslinking reaction could proceed due to insufficient heat resistance, even though they have crosslinking groups.

[0202] In addition, Comparative Example 1-4, which used a titanium compound reported in [Synthesis Example A-II] of Japanese Patent No. 6,189,758 as a compound having a metal different from the compound for forming a metal-containing film of the present invention, showed sufficient solvent resistance, but the difference in film thickness before and after the high-temperature additional bake treatment was large, and it was found that the volume shrinkage due to high-temperature bake was large compared to the compound for forming a metal-containing film of the present invention.

[0203] Examples 2-1 to 2-16, Comparative Examples 2-1 to 2-3 [Evaluation of embedding characteristics] The metal-containing film-forming compositions (UDL-1 to 16 and comparative examples UDL-3 to 5) that showed good film-forming properties after additional baking in the above solvent resistance evaluation were applied to a SiO2 wafer substrate having a dense line & space pattern (line width 40 nm, line depth 120 nm, distance between the centers of two adjacent lines 80 nm), and heated for 60 seconds at the temperature shown in Table 6 using a hot plate to form a metal-containing film with a thickness of 100 nm. The substrate used was a base substrate 9 (SiO2 wafer substrate) having a dense line & space pattern as shown in Figure 3 (Q) (overhead view) and (R) (cross-sectional view). The cross-sectional shape of each of the obtained wafer substrates was observed using an electron microscope (S-4700) manufactured by Hitachi, Ltd., and whether or not the stepped substrate could be filled was confirmed. The results are shown in Table 5. When a metal-containing film-forming composition with poor filling properties was used, the stepped substrate could not be filled well in this evaluation. When a metal-containing film-forming composition with good filling properties was used, the spaces between the lines of a base substrate 9 having a dense line and space pattern could be filled without gaps with a metal-containing film 10 in this evaluation, as shown in Figure 3(S). ◯ indicates that filling was possible without large voids, △ indicates that there were visible voids, and × indicates that filling was not possible.

[0204] [Table 6]

[0205] As shown in Table 6, in Examples 2-1 to 2-16 using the resist metal-containing film-forming composition of the present invention (UDL-1 to 16), it was possible to fill dense line and space patterns without generating voids, and it was confirmed that the composition has good filling properties. On the other hand, in Comparative Example 2-2 using the titanium compound reported in [Synthesis Example A-II] of Japanese Patent No. 6189758, voids were observed at the bottom of the pattern. As observed in the above solvent resistance evaluation, it is presumed that the voids were generated due to the large volume shrinkage caused by high-temperature baking.

[0206] Examples 3-1 to 3-16, Comparative Examples 3-1 to 3-3 [Flattening characteristics evaluation] For the base substrate 11 (SiO2 wafer substrate) having a dense line and space pattern as shown in Figure 4(T), the cross-sectional shape of each wafer substrate obtained in the above-mentioned filling property evaluation as shown in Figure 4(U) was observed using a scanning electron microscope (SEM), and the step (Delta 12 in Figure 4(U)) of the filling film (metal-containing film 12) between the dense line pattern part and the non-line pattern forming part was observed using an electron microscope (S-4700) manufactured by Hitachi, Ltd. The results are shown in Table 7. In this evaluation, it can be said that the smaller the step, the better the planarization property. [Table 7]

[0207] As shown in Table 7, in Examples 3-1 to 3-16 using the resist metal-containing film-forming composition (UDL-1 to 16) of the present invention, the step between the patterned portion and the non-patterned portion of the film was small compared to Comparative Example 3-2 using a titanium compound reported in [Synthesis Example A-II] of Japanese Patent No. 6189758 and Comparative Example 3-3 using an organic resist underlayer film material, and it was confirmed that the planarization characteristics were excellent. It was also confirmed that the planarization was excellent compared to Comparative Example 3-1 using a similar tin-containing compound. This is thought to be because the compound of the present invention has an asymmetric structure and contributes to improving thermal fluidity. In addition, Examples 3-14 and 3-16, which contained the high boiling point solvent (D-1) and the flow promoter (F-1), showed superior planarization characteristics compared to Examples 3-4 and 3-11, which did not contain the high boiling point solvent (D-1) and the flow promoter (F-1). It can be seen that the use of the high boiling point solvent (D-1) and the flow promoter (F-1) can further improve the thermal flowability of the metal-containing film-forming compound.

[0208] Examples 4-1 to 4-3, Comparative Examples 4-1 to 4-3 [Etching resistance evaluation] The metal-containing film-forming compositions (UDL-3, UDL-7, and UDL-9, and comparative examples UDL-3 to 5) that showed good film-forming properties after additional baking in the above solvent resistance evaluation were applied to a silicon substrate and heated using a hot plate at the temperatures shown in Table 8 for 60 seconds to form a metal-containing film with a thickness of 200 nm. An etching test was then performed using a CF-based gas and an O2-based gas under the following conditions to determine the difference in thickness of the organic film before and after etching. The results are shown in Table 8. A dry etching device TE-8500 manufactured by Tokyo Electron Limited was used for etching.

[0209] The CF4-based gas etching conditions are as follows: Chamber pressure 200mT RF power 300W CF4 gas flow rate: 100sccm Time 20sec

[0210] The O2-based gas etching conditions are as follows: Chamber pressure 500mT RF power 100W O2 gas flow rate: 30sccm N2 gas flow rate: 270sscm Time 20sec [Table 8]

[0211] As shown in Table 8, Comparative Example 4-1, which used a metal-containing film-forming composition similar to Examples 4-1 to 4-3 using the resist metal-containing film-forming composition of the present invention (UDL-3, 7, 9), and Comparative Example 4-2, which used a titanium compound (Comparative Example UDL-4), showed superior etching resistance to CF-based gases compared to Comparative Example 4-3, which used Comparative Example UDL-5, an organic resist underlayer film material, and the O2 etching resistance was even better.

[0212] [Pattern Forming Method (Examples 5-1 to 5-3, Comparative Examples 5-1 to 5-2)] The metal-containing film-forming compositions (UDL-3, UDL-7 and UDL-9, Comparative Examples UDL-4 to 5) that showed good film-forming properties after additional baking in the above solvent resistance evaluation were applied to a SiO2 wafer substrate having a trench pattern (trench width 10 μm, trench depth 0.10 μm), and baked in air at 250 ° C for 60 seconds to form a metal-containing film with a thickness of 100 nm. A silicon-containing resist intermediate layer material (SOG-1) was applied thereon and baked at 220 ° C for 60 seconds to form a resist intermediate layer film with a thickness of 30 nm, and a single layer resist for ArF of the resist upper layer film material was applied thereon and baked at 105 ° C for 60 seconds to form a photoresist film with a thickness of 100 nm. An immersion protective film material (TC-1) was applied on the photoresist film and baked at 90 ° C for 60 seconds to form a protective film with a thickness of 50 nm.

[0213] The silicon-containing resist intermediate layer material (SOG-1) was prepared by dissolving the polymer represented by ArF silicon-containing intermediate film polymer (SiP1) and the crosslinking catalyst (CAT1) in an organic solvent containing 0.1 mass% of FC-4430 (manufactured by Sumitomo 3M) in the ratios shown in Table 9, and filtering the solution through a fluorine resin filter having a pore size of 0.1 μm.

[0214] [Table 9]

[0215] The structural formulae of the ArF silicon-containing intermediate film polymer (SiP1) and crosslinking catalyst (CAT1) used are shown below. [ka]

[0216] The resist top layer film material (ArF single layer resist) was prepared by dissolving a polymer (RP1), an acid generator (PAG1), and a basic compound (Amine1) in a solvent containing 0.1 mass % of a surfactant FC-4430 (Sumitomo 3M Limited) in the ratios shown in Table 10, and filtering the solution through a 0.1 μm fluorine resin filter.

[0217] [Table 10]

[0218] The polymer (RP1), acid generator (PAG1), and basic compound (Amine1) used in the resist top layer material (ArF single layer resist) are shown below. [ka]

[0219] The immersion protective film material (TC-1) was prepared by dissolving the protective film polymer (PP1) in an organic solvent in the ratio shown in Table 11, and filtering through a 0.1 μm fluorine resin filter.

[0220] [Table 11]

[0221] The polymer (PP1) used in the immersion protective film material (TC-1) is shown below. [ka]

[0222] Next, the resist was exposed using an ArF immersion exposure tool (Nikon Corporation; NSR-S610C, NA 1.30, σ 0.98 / 0.65, 35 degree dipole s-polarized illumination, 6% halftone phase shift mask), baked at 100°C for 60 seconds (PEB), and developed in a 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution for 30 seconds to obtain a 55 nm 1:1 positive line and space pattern (resist pattern).

[0223] Next, the silicon-containing resist intermediate layer material (SOG-1) was etched by dry etching using the resist pattern as a mask to form a hard mask pattern, the metal oxide film was etched using the obtained hard mask pattern as a mask to form a metal oxide film pattern, and the SiO2 film was etched using the obtained metal oxide film pattern as a mask. The etching equipment used was ULVAC CE-3001, and the etching conditions were as follows:

[0224] Transfer conditions of resist pattern to silicon-containing resist intermediate layer material (SOG-1). Dry etching conditions with CF4 gas Pressure: 1Pa Antenna RF power: 100W Bias RF power: 15W CF4 gas flow rate: 15sccm Time: 60sec

[0225] Transfer conditions of SOG-1 hard mask pattern to metal-containing film. Pressure: 1Pa Antenna RF power: 320W Bias RF power: 30W Cl2 gas flow rate: 25sccm Time (Examples 5-1 to 5-3): 15 sec Time (Comparative Example 5-1 and Comparative Example 5-2): 60 sec

[0226] Transfer conditions of metal-containing film pattern onto SiO2 film. Dry etching conditions with CF4 gas Pressure: 1Pa Antenna RF power: 100W Bias RF power: 15W CF4 gas flow rate: 15sccm Time: 60sec

[0227] The cross section of the pattern was observed using an electron microscope (S-4700) manufactured by Hitachi, Ltd. The results are shown in Table 12.

[0228] [Table 12]

[0229] As shown in Table 12, in Examples 5-1 to 5-3 in which the metal oxide film-forming composition of the present invention (UDL-3, 7, 9) was used, the resist upper layer film pattern was successfully transferred to the substrate in the end, and it was confirmed that the metal oxide film-forming composition of the present invention is suitable for fine processing by the multilayer resist method. On the other hand, in Comparative Example 5-1 in which insufficient performance was confirmed in the embedding property evaluation and the planarization property evaluation, pattern collapse occurred during pattern processing, and ultimately, a good pattern could not be obtained. In addition, although there were no problems in the embedding property and planarization property evaluation, in Comparative Example 5-2 in which insufficient performance was confirmed in the dry etching resistance evaluation, distortion of the pattern shape occurred during pattern processing, and ultimately, a good pattern could not be obtained.

[0230] As described above, since the compound for forming a metal oxide film of the present invention is an organotin compound that highly balances thermal fluidity and thermosetting properties, a composition for forming a metal-containing film using this has excellent dry etching resistance compared to conventional organic underlayer film materials and can provide a metal-containing film such as a resist underlayer film material that also has high filling / planarization properties, and is extremely useful as a resist underlayer film material used in a multilayer resist method and as a reversal agent used in a tone reversal etching method.

[0231] The present specification includes the following aspects. [1]: A compound for forming a metal-containing film, characterized in that the compound is represented by the following general formula (M): [ka] In the above general formula (M), R1 and R2 each independently represent an organic group or a halogen atom, and W represents a divalent organic group represented by the following general formula (W-1) or (W-2): [ka] (In the general formula (W-1), l is an integer of 2 to 3; R3 and R4 each independently represent a substituted or unsubstituted linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a thiol group, a hydroxyl group, an amino group, a hydrogen atom or a halogen atom; or two of R3 and R4 on the same carbon form a carbonyl group together with the carbon to which they are bonded, and the alkyl group, the alkenyl group, the alkynyl group and the alkoxy group may have an ester group or an amide group. In addition, when two of R3 and R4 on the same carbon are bonded, In the general formula (W-2), R5 is independently a substituted or unsubstituted linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a thiol group, a hydroxyl group, an amino group, or a halogen atom, and the alkyl group, the alkenyl group, the alkynyl group, and the alkoxy group may have an ester group or an amide group, n is an integer of 0 to 1, m is an integer of 0 to 6, and * is a bonding site with -OSn. [2]: The compound for forming a metal-containing film according to [1], characterized in that in said general formula (M), said R1 is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted aliphatic unsaturated organic group having 2 to 20 carbon atoms containing one or more double bonds or triple bonds, 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. [3]: The compound for forming a metal-containing film according to [1] or [2], wherein R2 is -OC(=O)R2' (wherein R2' is a monovalent organic group). [4]: The compound for forming a metal-containing film according to [3], wherein R2' is any one of the following general formulae (A-1) to (A-4), (2) and (3): [ka] (In the above general formulae (A-1) to (A-4), Y A1 , Y A2 may be the same or different, and each represents 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, 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. A is a hydrogen atom, 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, 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 A1 is an organic group that generates one or more hydroxyl or carboxyl groups by elimination of a protecting group by the action of either or both of an acid and heat, as represented by the following general formula (1), and * represents a bond with a carbonyl group. [ka] (In the above general formula (1), R A2 is an organic group whose protecting group is removed by the action of either acid or heat, or both, and * is Y A1 Or Y A2) [ka] (In the general formula (2), X is a divalent organic group having 1 to 31 carbon atoms, B is the following general formula (B), and * represents a bond to a carbonyl group.) [ka] (In the above general formula (B), Y B represents a substituted or unsubstituted divalent saturated aliphatic hydrocarbon group having 1 to 20 carbon atoms or an unsaturated divalent aliphatic hydrocarbon group having 2 to 20 carbon atoms, a substituted or unsubstituted divalent aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted divalent arylalkyl group having 7 to 31 carbon atoms, which may be bonded to an adjacent group via an oxygen atom or an NH group; R B is a hydroxyl group or any of the structures represented by the following general formulas (B-1) to (B-3). * represents the bond with the carbonyl group. [ka] (In the above general formulas (B-1) to (B-3), R B1 is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, q is 0 or 1, * is Y B ) [ka] (In the general formula (3), X is a divalent organic group having 1 to 31 carbon atoms, C is a group represented by the following general formulas (C-1) to (C-4), and * represents a bond to a carbonyl group.) [ka] (In the above general formulas (C-1) and (C-3), R C1 are each independently a hydrogen atom or a methyl group, and in the same formula, they may be the same or different. In (C-3) to (C-4), R C2is a hydrogen atom, or a substituted or unsubstituted saturated or unsaturated monovalent aliphatic hydrocarbon 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. * represents the bond to the carbonyl group.) [5]: Y in the general formulae (A-1) to (A-4) A1 The compound for forming a metal-containing film according to [4], wherein X in the general formula (2) or X in the general formula (3) is a substituted or unsubstituted unsaturated hydrocarbon having 2 to 20 carbon atoms. [6]: Y in the general formulae (A-1) to (A-4) A1 The compound for forming a metal-containing film according to [4] or [5], wherein X in the general formula (2) or X in the general formula (3) is represented by the following general formula (4): [ka] (In the general formula (4), R a , R b and R C is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms, and R a and R b may be bonded to form a cyclic substituent. *1 and *2 each represent a bond to a carbonyl group, and the substitution positions of *1 and *2 may be reversed.) [7]: The compound for forming a metal-containing film according to any one of [1] to [6], characterized in that the ratio Mw / Mn of the weight average molecular weight Mw and the number average molecular weight Mn of the compound for forming a metal-containing film, as calculated using polystyrene standards, measured by a gel permeation chromatography method, is 1.00≦Mw / Mn≦1.50. [8]: A composition for forming a metal-containing film, which functions as a resist underlayer film material used in semiconductor manufacturing, characterized in that it contains (a) a compound for forming a metal-containing film according to any one of [1] to [7] and (b) an organic solvent. [9]: The composition for forming a metal-containing film according to [8], which is usable as a resist underlayer film in a multi-layer resist method, and further contains one or more of (c) a crosslinking agent, (d) a surfactant, (e) a flowability promoter, and (f) an acid generator.

[10] : The composition for forming a metal-containing film according to [8] or [9], characterized in that the (b) organic solvent is a mixture of one or more organic solvents having a boiling point of less than 180°C and one or more organic solvents having a boiling point of 180°C or higher.

[11] : A method for forming a pattern on a workpiece substrate, comprising: (I-1) A step of applying a composition for forming a metal-containing film according to any one of [8] to

[10] onto a substrate to be processed, and then performing a heat treatment to form a metal-containing film; (I-2) forming a resist top layer film on the metal-containing film using a photoresist material; (I-3) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (I-4) a step of transferring the pattern to the metal-containing film by dry etching using the resist top layer film on which the pattern is formed as a mask; and (I-5) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. A pattern forming method comprising the steps of:

[12] : A method for forming a pattern on a workpiece substrate, comprising: (II-1) A step of applying a composition for forming a metal-containing film according to any one of [8] to

[10] onto a substrate to be processed, and then performing a heat treatment to form a metal-containing film; (II-2) forming a resist intermediate film on the metal-containing film; (II-3) forming a resist upper layer film on the resist intermediate film using a photoresist material; (II-4) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (II-5) a step of transferring the pattern to the resist intermediate film by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (II-6) a step of transferring a pattern to the metal-containing film by dry etching using the resist intermediate film to which the pattern has been transferred as a mask; and (II-7) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. A pattern forming method comprising the steps of:

[13] : A method for forming a pattern on a workpiece substrate, comprising: (III-1) A step of applying a composition for forming a metal-containing film according to any one of [8] to

[10] onto a substrate to be processed, and then performing a heat treatment to form a metal-containing film; (III-2) forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film on the metal-containing film; (III-3) forming an organic thin film on the inorganic hard mask intermediate film; (III-4) forming a resist top layer film on the organic thin film using a photoresist material; (III-5) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (III-6) a step of transferring a pattern to the organic thin film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (III-7) A step of transferring a pattern to the metal-containing film by dry etching using the inorganic hard mask intermediate film to which the pattern has been transferred as a mask; and (III-8) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. A pattern forming method comprising the steps of:

[14] : A method for forming a pattern on a workpiece substrate, comprising: (IV-1) forming a resist underlayer film on a substrate to be processed; (IV-2) applying a composition for forming a metal-containing film according to any one of [8] to

[10] onto the resist underlayer film, and then subjecting the composition to a heat treatment to form a metal-containing film; (IV-3) forming a resist upper layer film on the metal-containing film using a photoresist material, or forming an organic adhesion film on the metal-containing film by spin coating, and forming a resist upper layer film thereon using a photoresist material; (IV-4) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (IV-5) a step of transferring a pattern to the metal-containing film, or the organic adhesion film and the metal-containing film, by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (IV-6) a step of transferring a pattern to the resist underlayer film by dry etching using the metal-containing film to which the pattern has been transferred as a mask; and (IV-7) A step of processing the substrate to be processed using the resist underlayer film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. A pattern forming method comprising the steps of:

[15] : A method for forming a pattern on a workpiece substrate, comprising: (V-1) a step of forming a resist underlayer film on a substrate to be processed; (V-2) a step of forming a 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 oxynitride film and an organic thin film on the resist underlayer film; (V-3) forming a resist upper layer film on the resist intermediate film or on a combination of the inorganic hard mask intermediate film and an organic thin film using a photoresist material; (V-4) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (V-5) a step of transferring a pattern to the resist intermediate film, or the organic thin film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (V-6) a step of transferring a pattern to the resist underlayer film by dry etching using the resist intermediate film or the inorganic hard mask intermediate film to which the pattern has been transferred as a mask; (V-7) a step of applying a composition for forming a metal-containing film according to any one of [8] to

[10] onto the resist underlayer film on which the pattern has been formed, and then heat-treating the composition to form a metal-containing film, thereby filling spaces between the resist underlayer film patterns with the metal-containing film; (V-8) a step of etching back the metal-containing film covering the resist underlayer film on which the pattern is formed by a chemical stripper or dry etching to expose the upper surface of the resist underlayer film on which the pattern is formed; (V-9) a step of removing the resist intermediate film or the hard mask intermediate film remaining on the upper surface of the resist underlayer film by dry etching; (V-10) a step of removing the resist underlayer film on which the pattern is formed and the surface is exposed by dry etching to form a reverse pattern of the original pattern on the metal-containing film; (V-11) A step of processing the substrate to be processed using the metal-containing film on which the reverse pattern is formed as a mask to form a reverse pattern on the substrate to be processed. A pattern forming method comprising the steps of:

[16] : The pattern formation method according to

[13] or

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

[0232] The present invention is not limited to the above-described embodiment. The above-described embodiment is merely an example, and anything that has substantially the same configuration as the technical idea described in the claims of the present invention and exhibits similar effects is included in the technical scope of the present invention. [Explanation of symbols]

[0233] 1... substrate to be processed, 2... layer to be processed, 2a... pattern (pattern to be formed on layer to be processed), 3...metal-containing film, 3a...metal-containing film pattern, 4...silicon-containing resist intermediate film, 4a...silicon-containing resist intermediate film pattern, 5...resist upper layer film, 5a...resist upper layer film pattern, 6...exposed portion, 7 ... a resist underlayer film made of a coating type organic underlayer film material; 7a ... a resist underlayer film pattern made of a coating type organic underlayer film material; 8...metal-containing film, 8a...metal-containing film pattern obtained by inverting the resist underlayer film pattern, 9...underlying substrate having dense lines and spaces; 10...metal-containing film; 11...underlying substrate having dense lines and spaces; 12...metal-containing film; Delta12: Step difference between the patterned portion and the non-patterned portion of the metal-containing film 12.

Claims

1. A compound for forming a metal-containing film, characterized in that the compound is represented by the following general formula (M): 【Chemistry 1】 (In the general formula (M), R １ , R ２ are each independently an organic group or a halogen atom, and W is a divalent organic group represented by the following general formula (W-1) or (W-2). 【Chemistry 2】 (In the general formula (W-1), l is an integer of 2 to 3, and R ３ , R ４ are each independently a substituted or unsubstituted linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a thiol group, a hydroxyl group, an amino group, a hydrogen atom, or a halogen atom, or R ３ , R ４ The two of R on the same carbon atom are carbonyl groups together with the carbon to which they are bonded, and the alkyl group, the alkenyl group, the alkynyl group, and the alkoxy group may have an ester group or an amide group. ３ , R ４ may be bonded to form a ring structure, and R on adjacent carbons may ３ , R ４ In the general formula (W-2), R ５ are each independently a substituted or unsubstituted linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 20 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a thiol group, a hydroxyl group, an amino group, or a halogen atom, the alkyl group, the alkenyl group, the alkynyl group, and the alkoxy group may have an ester group or an amide group, n is an integer of 0 to 1, m is an integer of 0 to 6, and * is a bond to -OSn.

2. In the general formula (M), the R １ is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 carbon atoms, a substituted or unsubstituted aliphatic unsaturated organic group having 2 to 20 carbon atoms and containing one or more double bonds or triple bonds, 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.

3. The R ２ -OC(=O)R ２ '(in the formula, R ２ 2. The compound for forming a metal-containing film according to claim 1, characterized in that:

4. The R ２ The compound for forming a metal-containing film according to claim 3, characterized in that ' is represented by the following general formula (A-1) to (A-4), or the following general formula (2), or the following general formula (3). 【Chemistry 3】 (In the above general formulae (A-1) to (A-4), Y Ａ１ , Y Ａ２ may be the same or different, and each represents 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, 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. Ａ is a hydrogen atom, 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, 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 Ａ１ is an organic group represented by the following general formula (1) in which a protecting group is eliminated by the action of either an acid or heat, or both, to generate one or more hydroxyl groups or carboxyl groups, and * represents a bond with a carbonyl group. 【Chemistry 4】 (In the general formula (1), R Ａ２ represents an organic group whose protecting group is removed by the action of either acid or heat, or both, and * represents Y Ａ１ Or Y Ａ２ It represents the bond with 【Chemistry 5】 (In the general formula (2), X is a divalent organic group having 1 to 31 carbon atoms, B is the following general formula (B), and * represents a bond to a carbonyl group.) 【Chemistry 6】 (In the above general formula (B), Y Ｂ represents a substituted or unsubstituted divalent saturated aliphatic hydrocarbon group having 1 to 20 carbon atoms or an unsaturated divalent aliphatic hydrocarbon group having 2 to 20 carbon atoms, a substituted or unsubstituted divalent aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted divalent arylalkyl group having 7 to 31 carbon atoms, which may be bonded to an adjacent group via an oxygen atom or an NH group; R Ｂ is a hydroxyl group or any of the structures represented by the following general formulas (B-1) to (B-3). * represents the bond with the carbonyl group. 【Chemistry 7】 (In the above general formulas (B-1) to (B-3), R Ｂ１ is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, q represents 0 or 1, * represents Y Ｂ It represents the bond with 【Chemistry 8】 (In the general formula (3), X is a divalent organic group having 1 to 31 carbon atoms, C is a group represented by the following general formulas (C-1) to (C-4), and * represents a bond to a carbonyl group.) 【Chemistry 9】 (In the general formulas (C-1) and (C-3), R Ｃ１ are each independently a hydrogen atom or a methyl group, and in the same formula, they may be the same or different. Ｃ２ is a hydrogen atom, or a substituted or unsubstituted, saturated or unsaturated monovalent aliphatic hydrocarbon 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. * represents the bond to the carbonyl group.)

5. Y in the general formulae (A-1) to (A-4) Ａ１ 5. The compound for forming a metal-containing film according to claim 4, wherein X in the general formula (2) or X in the general formula (3) is a substituted or unsubstituted unsaturated hydrocarbon having 2 to 20 carbon atoms.

6. Y in the general formulae (A-1) to (A-4) Ａ１ 5. The compound for forming a metal-containing film according to claim 4, wherein X in the general formula (2) or X in the general formula (3) is the following general formula (4): 【Chemistry 10】 (In the general formula (4), R ａ , R ｂ and R Ｃ is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; R ａ and R ｂ may be bonded to form a cyclic substituent. *1 and *2 each represent a bond to a carbonyl group, and the substitution positions of *1 and *2 may be reversed.)

7. The compound for forming a metal-containing film according to claim 1, characterized in that the ratio Mw / Mn of the weight average molecular weight Mw and the number average molecular weight Mn of the compound for forming a metal-containing film in terms of polystyrene measured by a gel permeation chromatography method is 1.00≦Mw / Mn≦1.

50.

8. A composition for forming a metal-containing film, which functions as a resist underlayer film material used in semiconductor manufacturing, comprising (a) the compound for forming a metal-containing film according to any one of claims 1 to 7 and (b) an organic solvent.

9. The composition for forming a metal-containing film according to claim 8, which is a composition for forming a metal-containing film that can be used as a resist underlayer film used in a multi-layer resist method, and further contains one or more of (c) a crosslinking agent, (d) a surfactant, (e) a flowability promoter, and (f) an acid generator.

10. The metal-containing film-forming composition according to claim 8, characterized in that the (b) organic solvent is a mixture of one or more organic solvents having a boiling point of less than 180°C and one or more organic solvents having a boiling point of 180°C or more.

11. A method for forming a pattern on a workpiece substrate, comprising the steps of: (I-1) A step of applying the composition for forming a metal-containing film according to claim 8 onto a substrate to be processed, followed by heat treatment to form a metal-containing film; (I-2) forming a resist top layer film on the metal-containing film using a photoresist material; (I-3) a step of pattern-exposing the resist upper layer film and then developing it with a developer to form a pattern on the resist upper layer film; (I-4) a step of transferring a pattern to the metal-containing film by dry etching using the resist top layer film on which the pattern is formed as a mask; and (I-5) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. A pattern forming method comprising the steps of:

12. A method for forming a pattern on a workpiece substrate, comprising the steps of: (II-1) A step of forming a metal-containing film by applying the composition for forming a metal-containing film according to claim 8 onto a substrate to be processed and then subjecting the substrate to a heat treatment; (II-2) forming a resist intermediate film on the metal-containing film; (II-3) forming a resist upper layer film on the resist intermediate film using a photoresist material; (II-4) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (II-5) a step of transferring the pattern to the resist intermediate film by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (II-6) A step of transferring a pattern to the metal-containing film by dry etching using the resist intermediate film to which the pattern has been transferred as a mask; and (II-7) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. A pattern forming method comprising the steps of:

13. A method for forming a pattern on a workpiece substrate, comprising the steps of: (III-1) A step of forming a metal-containing film by applying the composition for forming a metal-containing film according to claim 8 onto a substrate to be processed and then heat-treating the composition; (III-2) forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film on the metal-containing film; (III-3) forming an organic thin film on the inorganic hard mask intermediate film; (III-4) forming a resist top layer film on the organic thin film using a photoresist material; (III-5) a step of pattern-exposing the resist upper layer film and then developing the same with a developer to form a pattern on the resist upper layer film; (III-6) a step of transferring a pattern to the organic thin film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (III-7) A step of transferring a pattern to the metal-containing film by dry etching using the inorganic hard mask intermediate film to which the pattern has been transferred as a mask; and (III-8) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. A pattern forming method comprising the steps of:

14. A method for forming a pattern on a workpiece substrate, comprising the steps of: (IV-1) A step of forming a resist underlayer film on a substrate to be processed; (IV-2) A step of forming a metal-containing film by applying the composition for forming a metal-containing film according to claim 8 onto the resist underlayer film and then heat-treating the composition; (IV-3) forming a resist upper layer film on the metal-containing film using a photoresist material, or forming an organic adhesion film on the metal-containing film by spin coating, and forming a resist upper layer film thereon using a photoresist material; (IV-4) a step of pattern-exposing the resist upper layer film and then developing the same with a developer to form a pattern on the resist upper layer film; (IV-5) a step of transferring a pattern to the metal-containing film, or the organic adhesion film and the metal-containing film, by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (IV-6) a step of transferring a pattern to the resist underlayer film by dry etching using the metal-containing film to which the pattern has been transferred as a mask; and (IV-7) A step of processing the substrate to be processed using the resist underlayer film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. A pattern forming method comprising the steps of:

15. A method for forming a pattern on a workpiece substrate, comprising the steps of: (V-1) A step of forming a resist underlayer film on a substrate to be processed; (V-2) a step of forming a 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 oxynitride film and an organic thin film on the resist underlayer film; (V-3) forming a resist upper layer film on the resist intermediate film or the combination of the inorganic hard mask intermediate film and the organic thin film using a photoresist material; (V-4) a step of pattern-exposing the resist upper layer film and then developing it with a developer to form a pattern on the resist upper layer film; (V-5) a step of transferring a pattern to the resist intermediate film, or the organic thin film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (V-6) A step of transferring a pattern to the resist underlayer film by dry etching using the resist intermediate film or the inorganic hard mask intermediate film to which the pattern has been transferred as a mask; (V-7) a step of applying the composition for forming a metal-containing film according to claim 8 onto the resist underlayer film on which the pattern has been formed, and then heat-treating the composition to cover the metal-containing film and fill spaces between the resist underlayer film patterns with the metal-containing film; (V-8) a step of etching back the metal-containing film covering the resist underlayer film on which the pattern has been formed by a chemical stripper or dry etching to expose the upper surface of the resist underlayer film on which the pattern has been formed; (V-9) A step of removing the resist intermediate film or the hard mask intermediate film remaining on the upper surface of the resist underlayer film by dry etching; (V-10) a step of removing the resist underlayer film having the pattern formed thereon and having an exposed surface by dry etching to form a reverse pattern of the original pattern in the metal-containing film; (V-11) A step of processing the substrate to be processed using the metal-containing film on which the reverse pattern is formed as a mask to form a reverse pattern on the substrate to be processed. A pattern forming method comprising the steps of:

16. 14. The pattern formation method according to claim 13, wherein the inorganic hard mask intermediate film is formed by a CVD method or an ALD method.

17. 16. The pattern formation method according to claim 15, wherein the inorganic hard mask intermediate film is formed by a CVD method or an ALD method.

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