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

Abstract

To provide a patterning process used for a resist underlayer film material having excellent dry etching resistance.SOLUTION: A compound for forming a metal-containing film is represented by the general formula (M) in the figure, where each T independently represents the general formula (T-1) or (T-2) in the figure; P independently represents *OCOR, where the asterisk represents an attachment point to the Sn atom and R represents a monovalent organic group; each Q independently represents a C1-20 alkyl group, cycloalkyl group, aliphatic unsaturated hydrocarbon group, alkoxy group, or C6-30 aryl group.SELECTED DRAWING: Figure 1

Description

Technical Field

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

Background Art

[0002] With the increasing integration and speed of LSIs, the miniaturization of pattern rules has been rapidly progressing. As the most advanced miniaturization technology, ArF immersion lithography has been applied to the mass production of devices since the 45 nm node. In addition, together with ArF immersion exposure, a double patterning process has been put into practical use in generations after the 28 nm node, enabling the formation of narrow pitch patterns beyond the optical limit.

[0003] Furthermore, in the manufacture of devices after the 20 nm node, a multiple patterning process of repeating exposure and etching three or more times to produce patterns with a narrower pitch is being studied. However, since the multiple patterning process increases the number of steps, the productivity is reduced due to the lengthening of the manufacturing period and the increase in the frequency of defect occurrence, and the cost is significantly increased.

[0004] In recent years, extreme ultraviolet (EUV) lithography with a wavelength of 13.5 nm has attracted attention as a promising technology to replace the combined use of ArF immersion lithography and the multiple patterning process. By 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, in order to compensate for the insufficient output of the light source, high sensitivity is strongly required for the resist material. However, the increase in shot noise accompanying the increase in sensitivity leads to an increase in the edge roughness (LER, LWR) of the line pattern, and the compatibility between high sensitivity and low edge roughness is one of the important issues in EUV lithography.

[0006] In recent years, in an attempt to increase the sensitivity of resists and reduce the influence of shot noise, the use of metal materials in resist materials has been under consideration. Compounds containing metal elements such as barium, titanium, hafnium, zirconium, and tin have a higher absorbance for EUV light compared to organic materials without metals, and it is expected that the photosensitivity of the resist can be improved and the influence of shot noise can be suppressed. In addition, by combining a metal-containing resist pattern with an underlying film made of a non-metallic material, highly selective etching can be expected.

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

[0008] Among them, molecules containing tin are excellent in absorbing electron beams and extreme ultraviolet rays, and thus active research is being conducted. In the case of an organotin polymer, which is one of them, the alkyl ligand is dissociated by light absorption or secondary electrons generated thereby, and negative tone patterning that cannot be removed with an organic developer through crosslinking through an oxo bond with the peripheral chain is possible. Such an organotin polymer can improve the sensitivity while maintaining the resolution and line edge roughness, but has not yet reached the level of commercialization (Patent Document 5). In addition, many problems remain, such as insufficient storage stability regarding changes in resist sensitivity.

[0009] Regarding the above problems, the development using materials containing metal elements such as titanium, hafnium, zirconium, and tin in the resist underlying film has also been studied. It is not necessary to improve the performance such as improving the exposure sensitivity, which is a problem in metal-containing resist materials, and suppressing the sensitivity change in the storage environment. By containing the above metal elements, it may be possible to provide a resist underlying film with excellent dry etching resistance. Patent Document 7 reports that a material using a Ti compound exhibits excellent dry etching resistance against CHF3 / CF4-based gases and CO2 / N2-based gases.

[0010] On the one hand, when using a metal compound for a resist underlayer film, problems include film-forming properties and embedding properties. For example, in the case of a compound assumed to be used in a photoresist such as Patent Document 6, heat resistance is not mentioned, but since high-temperature baking is not assumed, there is a lack of heat resistance, and there is a risk of poor embedding and film-forming properties. Also, in Patent Document 7, film-forming properties and embedding properties are not mentioned, but generally, metal oxide compounds have a large thermal shrinkage during baking and induce a significant deterioration in filling properties after high-temperature baking. Therefore, there is a concern that they are insufficient as a resist underlayer film material that requires heat resistance characteristics such as film-forming properties and embedding characteristics. In Patent Document 8, it is reported that a metal compound modified with a specific ligand has excellent embedding properties, but the baking temperature for the implemented embedding property evaluation is as low as 150 °C, and there is a concern that it is insufficient as a resist underlayer film that requires heat resistance (for example, characteristics against heat treatment that may be performed after forming the resist underlayer film). In Patent Document 9, by mixing the metal compound reported in Patent Document 8 with an organic polymer having a specific structure, a resist underlayer film material excellent in embedding properties after baking at 400 °C is provided. However, since it is a mixed composition of an inorganic metal compound and an organic polymer, there are concerns about film-forming defects caused by poor compatibility, deterioration of storage stability, and deterioration of dry etching resistance.

Prior Art Documents

Patent Documents

[0011]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Patent Document 8

Patent Document 9

Summary of the Invention

Problems to be Solved by the Invention

[0012] The present invention has been made in view of the above circumstances, and provides 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 film-forming properties and a high tin content. Another object of the present invention is to provide a composition for forming a metal-containing film using the compound, and a patterning method using the composition as a resist underlayer film material.

Means for Solving the Problems

[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).

Chemical Formula

[0014] For such a compound containing tin, radicals are generated by radical cleavage of the Sn-alkyl bond, and thus crosslinking reactions occur due to these radicals. Also, since tin is bonded to the unit (T) having catechol or diol, a plurality of tin atoms can be introduced into one molecule, so the tin content can be increased. Further, in the above general formula (M), when n2 is 1 or when n1 is 2 and T is different, the molecular symmetry is broken, so the solvent solubility can be increased. Therefore, the compound of the present invention has excellent solvent solubility, is suitable as a composition for forming a metal film, and can form a film with a high tin content when used as a resist underlayer film.

[0015] In the above compound, (i) in the general formula (T-1), it is preferable that W1 is any of a linear, branched or cyclic saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms which may contain a hydroxyl group or an amino group (including an aromatic ring group) (the hydrocarbon group contains an oxygen atom, a nitrogen atom, a sulfur atom and may form an ether bond, a carbonyl group, an ester group) or a group represented by the following general formulas (W1-1) to (W1-4).

Chemical formula

[0016] Also, in the above compound, (ii) in the general formula (T-2), it is also preferable that W2 is any of a linear, branched or cyclic saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms which may contain a hydroxyl group or an amino group (including an aromatic ring group), or a cyclic hydrocarbon group bonded to R3 (the hydrocarbon group contains an oxygen atom, a nitrogen atom, a sulfur atom and may form an ether bond, a carbonyl group, an ester group), or a group represented by the following general formulas (W2-1) to (W2-4).

Chemical formula

[0017] If W1 in the general formula (T-1) and / or W2 in (T-2) has the above structure, the proportion of the organic group can be suppressed and the tin content can be increased.

[0018] Further, in the general formulas (W1-1) to (W1-4) of (i) and / or R in the general formulas (W2-1) to (W2-4) of (ii) W is preferably an unsaturated hydrocarbon group having 2 to 23 carbon atoms.

[0019] If R in the general formulas (W1-1) to (W1-4) and (W2-1) to (W2-4) W is an unsaturated hydrocarbon group having 2 to 23 carbon atoms, the thermosetting property of the above compound can be further improved.

[0020] Further, in the present invention, the R in the general formulas (W1-1) to (W1-4) of (i) and / or the general formulas (W2-1) to (W2-4) of (ii) W can be a group represented by the following general formula (1).

Chemical formula

[0021] In the general formulas (W1-1) to (W1-4) and (W2-1) to (W2-4), R WIf it is a group represented by the above general formula (1), it is possible to achieve both thermosetting properties and a high tin content. When this is used in a composition for forming a metal-containing film, it is possible to provide a resist underlayer film material that exhibits more excellent film-forming properties and a high tin content.

[0022] Further, in the general formula (M), it is preferable that n2 is 1 and R of *OCOR of P is any one of the groups represented by the following general formulas (A-1) to (A-4), the following general formula (3), and the following general formula (4).

Chemical formula

Chemical formula

Chemical formula

[0023] If R has the structure represented by the above general formulas (A-1) to (A-4), since the structure contains an organic group in which a protecting group is eliminated by the action of either or both of a bulky acid and heat, the solvent solubility of the compound can be increased. Further, when this is used in a composition for forming a metal-containing film, the protecting group is eliminated during baking, and a hydroxyl group or a carboxyl group is generated. The α-hydrogen of the thus-generated OH or carboxylic acid easily reacts with the radicals generated by the cleavage of the tin-carbon bond during baking and causes a crosslinking reaction. Therefore, the compound of the present invention is excellent in thermosetting properties and can suppress the volume shrinkage that induces deterioration of film-forming properties and embedding properties. Further, even during high-temperature baking, a resist underlayer film material excellent in film-forming properties and embedding characteristics can be provided.

[0024] Also, if R has the structure represented by the above general formula (3), it contains a hydroxyl group at the terminal or a crosslinking group having any of the structures represented by the above general formulas (B-1) to (B-3). Therefore, when these are used in a composition for forming a metal-containing film, during baking, not only the crosslinking reaction between radicals generated by the cleavage of the tin-carbon bond but also the reaction between radicals and crosslinking groups and the reaction between crosslinking groups occur, and further crosslinking reactions occur, so it is excellent in thermosetting properties and can suppress the volume shrinkage that induces deterioration of film-forming properties and embedding properties. Even after high-temperature baking, a resist underlayer film material excellent in film-forming properties and embedding characteristics can be provided.

[0025] And if R has the structure represented by the above general formula (4), it contains any of the structures represented by (C-1) to (C-4) at the terminal, and the structure has a high crosslinking group density and is excellent in thermosetting properties. Therefore, when this is used in a composition for forming a metal-containing film, the volume shrinkage during baking is small, and even after high-temperature baking, a resist underlayer film material excellent in film-forming properties and embedding characteristics can be provided.

[0026] Y in the above general formulas (A-1) to (A-4) A1 , X in the above general formula (3), or X in the above general formula (4) is preferably an unsaturated hydrocarbon group having 2 to 23 carbon atoms.

[0027] Y in the above general formulas (A-1) to (A-4)A1 If X in the general formula (3) above or X in the general formula (4) above is an unsaturated hydrocarbon group having 2 to 23 carbon atoms, the thermosetting property of the metal-containing film-forming compound can be further improved.

[0028] In this case, Y in the general formulas (A-1) to (A-4) above A1 X in the general formula (3) above or X in the general formula (4) above can be a group represented by the following general formula (1). [Chemical formula] (In the general formula (1), R a , R b and R c are 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 bonding portion with a carbonyl group, and *1 and *2 may be reversed.)

[0029] Y in the general formulas (A-1) to (A-4) above A1 If X in the general formula (3) above or X in the general formula (4) above is a group represented by the following general formula (1), it becomes possible to enhance the thermosetting property, and when these are used in a metal-containing film-forming composition, a resist underlayer film material showing more excellent film-forming property can be provided.

[0030] Further, the present invention can provide a metal-containing film-forming composition that functions as a resist underlayer film material used in semiconductor manufacturing, which contains (a) the above metal-containing film-forming compound and (b) an organic solvent.

[0031] For such a metal-containing film-forming composition, since it contains an organotin compound excellent in solvent solubility and heat resistance, it has excellent dry etching resistance with respect to conventional organic underlayer film materials and can provide a resist underlayer film material having a high degree of film-forming property.

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

[0033] Moreover, it is preferable that the above (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.

[0034] By imparting thermal fluidity to the above compound for forming a metal-containing film by adding a high-boiling solvent, the planarization characteristics of the composition for forming a resist underlayer film can be further improved.

[0035] Moreover, the present invention is a method for forming a pattern on a substrate to be processed, comprising: (I-1) A step of forming a metal-containing film by applying the composition for forming a metal-containing film of the present invention on a substrate to be processed and then performing a heat treatment; (I-2) A step of forming a resist upper layer film on the metal-containing film using a photoresist material; (I-3) A step of forming a pattern on the resist upper layer film by pattern exposure and then developing with a developer; (I-4) A step of transferring the pattern to the metal-containing film by dry etching using the resist upper 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 is formed as a mask to form a pattern on the substrate to be processed. A pattern forming method is provided, which is characterized by having the above steps.

[0036] By the above pattern forming method using a two-layer resist process, a fine pattern can be formed on a workpiece (substrate to be processed).

[0037] Moreover, the present invention is a method for forming a pattern on a substrate to be processed, comprising: (II-1) A step of forming a metal-containing film by applying the composition for forming a metal-containing film of the present invention on a substrate to be processed and then performing heat treatment. (II-2) A step of forming a resist intermediate film on the metal-containing film. (II-3) A step of forming a resist upper layer film using a photoresist material on the resist intermediate film. (II-4) A step of performing pattern exposure on the resist upper layer film and then developing with a developer to form a pattern on the resist upper layer film. (II-5) A step of transferring the pattern to the resist intermediate film by dry etching using the resist upper layer film with the pattern formed as a mask. (II-6) A step of transferring the pattern to the metal-containing film by dry etching using the resist intermediate film with the pattern transferred as a mask, and (II-7) A step of 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. provided is a pattern formation method characterized by comprising the above steps.

[0038] By the pattern formation method using the above three-layer resist process, a fine pattern can be formed on a workpiece with high precision.

[0039] Further, the present invention is a method for forming a pattern on a substrate to be processed, comprising: (III-1) A step of forming a metal-containing film by applying the composition for forming a metal-containing film of the present invention on a substrate to be processed and then performing heat treatment. (III-2) A step of forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film on the resist lower layer film. (III-3) A step of forming an organic thin film on the inorganic hard mask intermediate film. (III-4) A step of forming a resist upper layer film using a photoresist material on the organic thin film. (III-5) A step of performing pattern exposure on the resist upper layer film and then developing with a developer to form a pattern on the resist upper layer film. (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 is 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 on which the pattern is 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 is formed as a mask to form a pattern on the substrate to be processed provided is a pattern formation method characterized by comprising the above steps.

[0040] By the pattern formation method using the above four-layer resist process, a fine pattern can be formed on the object to be processed with high precision.

[0041] In this case, it is preferable to form the inorganic hard mask intermediate film by a CVD method or an ALD method.

[0042] When the inorganic hard mask is formed by a CVD method or an ALD method, a fine pattern can be formed on the object to be processed with higher precision.

[0043] Further, the present invention is a method for forming a pattern on a substrate to be processed, comprising: (IV-1) A step of forming a resist lower layer film on the substrate to be processed, (IV-2) A step of forming a metal-containing film by applying the composition for forming a metal-containing film of the present invention on the resist lower layer and then performing heat treatment, (IV-3) A step of forming a resist upper layer film on the metal-containing film using a photoresist material, or a step of forming an organic adhesion film by spin coating on the metal-containing film and then forming a resist upper layer film on the organic adhesion film using a photoresist material, (IV-4) A step of forming a pattern on the resist upper layer film by pattern exposure and then developing with a developer, (IV-5) Using the resist upper layer film on which the pattern is formed as a mask, transferring the pattern to the metal-containing film, or the organic adhesion film and the metal-containing film by dry etching; (IV-6) Using the metal-containing film on which the pattern is transferred as a mask, transferring the pattern to the resist lower layer film by dry etching; and (IV-7) Using the resist lower layer film on which the pattern is formed as a mask, processing the substrate to be processed to form a pattern on the substrate to be processed. provided is a pattern forming method characterized by comprising the above steps.

[0044] By the pattern forming method using the above multilayer resist process, a fine pattern can be formed on the object to be processed with high precision.

[0045] Further, the present invention is a method for forming a pattern on a substrate to be processed, comprising: (V-1) forming a resist lower layer film on the substrate to be processed; (V-2) forming, on the resist lower layer film, a combination of a resist intermediate film, or 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; (V-3) 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; (V-4) after pattern exposing the resist upper layer film, developing with a developer to form a pattern on the resist upper layer film; (V-5) using the resist upper layer film on which the pattern is formed as a mask, transferring the pattern to the resist intermediate film, or the organic thin film and the inorganic hard mask intermediate film by dry etching; (V-6) using the resist intermediate film, or the inorganic hard mask intermediate film on which the pattern is transferred as a mask, transferring the pattern to the resist lower layer film by dry etching; (V-7) On the resist underlayer film on which the pattern is formed, after applying the composition for forming a metal-containing film of the present invention and performing heat treatment, a metal-containing film is coated, and the spaces between the resist underlayer film patterns are filled with the metal-containing film. (V-8) 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) 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) Removing the resist underlayer film on which the pattern is formed with the exposed surface by dry etching to form an inverted pattern of the original pattern in the metal-containing film. (V-11) Using the metal-containing film on which the inverted pattern is formed as a mask to process the substrate to be processed and forming an inverted pattern on the substrate to be processed. provided is a pattern formation method characterized by having the above steps.

[0046] By the pattern formation method by the above inversion process, a finer pattern can be formed on the object to be processed with higher precision.

[0047] Also in this case, it is preferable to form the inorganic hard mask intermediate film by a CVD method or an ALD method.

[0048] When the inorganic hard mask is formed by a CVD method or an ALD method, a finer pattern can be formed on the object to be processed with higher precision.

Effects of the Invention

[0049] As described above, since the compound for forming a metal-containing film of the present invention is a compound represented by the above general formula (M), radicals are generated by radical cleavage of the Sn-alkyl bond during baking, and a crosslinking reaction occurs due to the radicals. In addition, since tin is bonded to the unit having catechol or diol, a plurality of tin atoms can be introduced into one molecule, so that the tin content can be increased. Further, in the above general formula (M), when n2 is 1 or n1 is 2 and T is different, the molecular symmetry is broken, so that the solvent solubility can be increased. Therefore, the composition using the compound of the present invention can provide a resist underlayer film material having excellent solvent solubility and a high tin content. In particular, in a fine patterning process using a multilayer resist method in a semiconductor device manufacturing process, even on a substrate to be processed having a portion where embedding / flattening is difficult, such as a dense portion of a high aspect ratio fine pattern structure typified by a DRAM memory with increasing miniaturization, it is possible to embed without causing defects such as voids or peeling. Further, since it has excellent dry etching resistance compared to a conventional coating-type organic resist underlayer film material, a finer pattern can be formed on the workpiece with higher accuracy compared to an organic resist underlayer film. In addition, since the composition for forming a metal-containing film containing the compound for forming a metal-containing film of the present invention contains tin atoms with a large EUV light absorption, there is a sensitizing effect by secondary electrons generated therefrom during exposure. Further, since the tin atom has a large atomic weight, it has a high effect of suppressing acid diffusion from the upper layer resist into the resist underlayer film, and has the characteristic that it can be made highly sensitive while maintaining the LWR performance originally possessed by the upper layer resist film.

Brief Description of the Drawings

[0050]

Figure 1

Figure 2

Figure 3

BEST MODE FOR CARRYING OUT THE INVENTION

[0051] As described above, in the fine patterning process using a multilayer resist method, there has been a demand for the development of a composition for forming a metal-containing film having excellent film-forming properties used for forming a resist underlayer film capable of transferring a resist pattern to a substrate to be processed with higher accuracy, and a compound for forming a metal-containing film useful for the composition.

[0052] The present inventors focused on an organotin compound expected to play an active role in EUV exposure generations and conducted intensive studies. As described above, tin atoms with large EUV light absorption have a sensitizing effect by secondary electrons that will be generated during exposure, and have the characteristic that they can be made highly sensitive while maintaining the LWR performance originally possessed by the resist upper layer film. On the other hand, the organotin compounds being considered as the resist upper layer film have poor heat resistance and cause a rapid volume contraction during baking, so it is difficult to form a uniform film or fill the steps of the substrate to be processed when baked at a high temperature. The present inventors considered that if an organic molecule having a diol structure (including catechol) and a carboxylate in the molecule reacts with a tin compound, it is possible to increase the molecular weight while introducing a plurality of tin atoms into the molecule, and even if the bond is broken during baking, it is highly likely that a sufficient molecular weight can be maintained, sublimates can be suppressed, heat resistance can be improved, and excellent film-forming properties can be exhibited. In addition, since a plurality of tin atoms can be introduced into one molecule, it is possible to increase not only the heat resistance but also the tin content, and it was considered that a composition for forming a metal-containing film exhibiting excellent etching resistance would be obtained. Therefore, the present inventors conducted further intensive studies and found that a compound for forming a metal-containing film represented by the above general formula (M) has excellent film-forming properties and can further increase the tin content, so that it becomes a compound for forming a metal-containing film having excellent etching resistance, and completed the present invention.

[0053] That is, the present invention is a metal-containing film-forming compound that can be used in a composition for forming a metal-containing film that functions as a resist underlayer film material used in semiconductor manufacturing, and the compound is represented by the following general formula (M). A metal-containing film-forming compound characterized by the above. [Chemical formula] (In the general formula (M), T is independently the following general formula (T-1) or (T-2), P is independently *OCOR (* represents the bonding part with the Sn atom, and R represents a monovalent organic group), and Q is independently 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 hydrocarbon 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, a substituted or unsubstituted arylalkyl group having 7 to 31 carbon atoms, a halogen atom, or an alkoxy group having 1 to 20 carbon atoms. Further, n1, n2, and n3 are integers such that n1 ≧ 1, n2 ≧ 0, n3 ≧ 1, and n1 + n2 + n3 = 4. When n1 ≧ 2, the Ts may be the same or different from each other. When n2 = 2, the Ps may be the same or different from each other. When n3 ≧ 2, the Qs may be the same or different from each other.) [Chemical formula] (In the general formulas (T-1) and (T-2), 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 hydrocarbon 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 * is the bonding portion with the Sn atom in the general formula (M). W1 is a substituted or unsubstituted linear, branched or cyclic saturated or unsaturated hydrocarbon group having 1 to 40 carbon atoms (including an aromatic ring group), and the hydrocarbon group contains an oxygen atom, a nitrogen atom, or a sulfur atom as a heteroatom, and may form an ether bond, a carbonyl group, an ester group, or an amide group, and may form a heterocyclic structure through the heteroatom. R2 represents 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 hydrocarbon group having 2 to 20 carbon atoms containing one or more double bonds or triple bonds, a hydroxyl group, an amino group, or a halogen atom, s1 is an integer of 0 to 1, and m is an integer of 0 to 1. W2 is a substituted or unsubstituted linear, branched or cyclic saturated or unsaturated hydrocarbon group having 1 to 40 carbon atoms (including an aromatic ring group), and the hydrocarbon group contains an oxygen atom, a nitrogen atom, or a sulfur atom as a heteroatom, and may form an ether bond, a carbonyl group, an ester group, or an amide group, and may form a heterocyclic structure through the heteroatom. s2 is an integer of 0 to 1. s3 is 1 or 2. When s3 is 1, R3 is a hydrogen atom or a hydrocarbon group having a hydroxyl group with 1 to 10 carbon atoms. When s3 is 2, R3 is an oxygen atom and together with the carbon atom to which it is bonded forms a carbonyl group, and W2 and R3 may be bonded to each other to form a ring structure.)

[0054] Hereinafter, the present invention will be described in detail, but the present invention is not limited thereto. Although catechol (1,2-benzenediol) is included in diols, in this specification, a compound having a 1,2-benzenediol structure is referred to as catechol, and other diols may be simply referred to as "diols".

[0055] <Compound for forming a metal-containing film> The compound for forming a metal-containing film of the present invention is a compound for forming a metal-containing film, which is characterized by being represented by the following general formula (M). The compound can be used in a composition for forming a metal-containing film that functions as a resist underlayer film material used in semiconductor manufacturing.

Chemical formula

Chemical formula

[0056] In the general formula (M) above, P is independently *OCOR (* represents the bonding part with the Sn atom, and R represents a monovalent organic group). R is, for example, a linear hydrocarbon group such as a methyl group, an ethyl group, an n-butyl group, a branched hydrocarbon group such as an isopropyl group or a tert-butyl group, a cyclic hydrocarbon group such as cyclohexane or cyclopropane, or other ether groups, ester groups, amide groups, aryl groups, arylalkyl groups, or groups containing an unsaturated bond. These may be substituted or unsubstituted, and there is no particular limitation as long as they are groups derived from monovalent carboxylic acids. From the perspective of crosslinkability, it is preferably a structure containing an unsaturated bond, a hydroxyl group, or a structure in which a protecting group is eliminated by heat or an acid to generate a hydroxyl group or a carboxyl group. In the following, for the purpose of representing a primary alkyl group name, it may be described as n, and for representing a secondary and tertiary alkyl group, it may be described as s, t, sec-, tert-, etc., respectively.

[0057] In the general formula (M) above, Q is independently 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 hydrocarbon 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, a substituted or unsubstituted arylalkyl group having 7 to 31 carbon atoms, a halogen atom, or an alkoxy group having 1 to 20 carbon atoms. From the perspective of raw material availability, it is preferably an n-butyl group, a t-butyl group, an n-octyl group, a benzyl group, a halogen atom, or an alkoxy group, and more preferably an n-butyl group. Also, considering the ease of radical cleavage of the Sn-alkyl bond, a t-butyl group and a benzyl group are also preferred.

[0058] In the above general formula (M), T is independently the above general formula (T-1) or (T-2). In general formulas (T-1) to (T-2), 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 hydrocarbon 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, a substituted or unsubstituted arylalkyl group having 7 to 31 carbon atoms, or a combination thereof. From the viewpoint of raw material availability, it is preferably an n-butyl group, a t-butyl group, an n-octyl group, or a benzyl group, more preferably an n-butyl group. Also, considering the ease of radical cleavage of the Sn-alkyl bond, the t-butyl group and the benzyl group are also preferred.

[0059] In the above general formula (M), n1, n2, and n3 are integers such that n1≥1, n2≥0, n3≥1, and n1 + n2 + n3 = 4. When n1≥2, the Ts may be the same or different from each other. When n2 = 2, the Ps may be the same or different from each other. When n3≥2, the Qs may be the same or different from each other. From the viewpoint of increasing the tin content rate, it is preferably n1 = 3 and n3 = 1. From the viewpoint of disrupting the molecular symmetry and increasing the solubility, it is preferably n1 = 2, n2 = 1, and n3 = 1.

[0060] In the general formula (T-1) above, W1 is a linear, branched or cyclic saturated or unsaturated hydrocarbon group having 1 to 40 carbon atoms, which may be substituted or unsubstituted (including aromatic groups), and the hydrocarbon group contains an oxygen atom, a nitrogen atom or a sulfur atom as a heteroatom, and may form an ether bond, a carbonyl group, an ester group or an amide group, and may form a heterocyclic structure through the heteroatom such as through an amide group or an ester group. However, from the viewpoints of heat resistance and increase in Sn content, it is preferable that W1 is a linear, branched or cyclic saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms which may contain a hydroxyl group or an amino group (the hydrocarbon group contains an oxygen atom, a nitrogen atom or a sulfur atom as a heteroatom and may form an ether bond, a carbonyl group or an ester group). s1 is an integer of 0 to 1. From the viewpoint of increasing the tin content, it is preferable that s1 is 0, and from the viewpoints of thermal fluidity and embedability, it is preferable that s1 is 1 because it is better to contain an organic chain. When s1 is 0, it means that the carbonyl group is singly bonded.

[0061] More specifically, it is preferable that W1 is any one of a linear, branched or cyclic saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms which may contain a hydroxyl group or an amino group (the hydrocarbon group contains an oxygen atom, a nitrogen atom or a sulfur atom as a heteroatom and may form an ether bond, a carbonyl group or an ester group) or a group represented by the following general formulas (W1-1) to (W1-4). [Chemical formula] (In the general formulas (W1-1) to (W1-4) above, R W is a divalent organic group having 1 to 23 carbon atoms, and #1 and #2 each represent a bonding portion with an ester or a benzene ring.)

[0062] In the general formula (T-1), R2 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 hydrocarbon group having 2 to 20 carbon atoms containing one or more double bonds or triple bonds, a hydroxyl group, an amino group, or a halogen atom, and is preferably a hydroxyl group from the viewpoint of thermosetting properties.

[0063] More specific examples of the formula (T-1) include, but are not limited to, the following formulas. (In the following formulas, R1 and R w represent the same groups as described above.)

Chemical formula

[0064] In the general formula (T-2), W2 is a substituted or unsubstituted linear, branched, or cyclic saturated or unsaturated hydrocarbon group having 1 to 40 carbon atoms (including an aromatic group), the hydrocarbon group may contain an oxygen atom, a nitrogen atom, or a sulfur atom, and may form an ether bond, a carbonyl group, an ester group, or an amide group, and may form a heterocyclic structure through an amide group, an ester group, etc. However, from the viewpoints of heat resistance and increasing the Sn content, W2 is preferably a linear, branched, or cyclic saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms (including an aromatic group) that may contain a hydroxyl group or an amino group (the hydrocarbon may contain an oxygen atom, a nitrogen atom, or a sulfur atom and may form an ether bond, a carbonyl group, or an ester group).

[0065] More specifically, W2 is preferably a linear, branched, or cyclic saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms (including an aromatic ring group) that may contain a hydroxyl group or an amino group, or a cyclic hydrocarbon group bonded to R3 (the hydrocarbon group may contain an oxygen atom, a nitrogen atom, or a sulfur atom and may form an ether bond, a carbonyl group, or an ester group), or any of the groups represented by the following general formulas (W2-1) to (W2-4).

Chemical formula

[0066] In the general formula (T-2) above, s3 is 1 or 2. When s3 is 1, R3 is a hydrogen atom or a hydrocarbon group having a hydroxyl group with 1 to 10 carbon atoms. When s3 is 2, R3 is an oxygen atom and together with the carbon atom to which it is bonded forms a carbonyl group. W2 and R3 may be bonded to each other to form a ring structure. s2 is an integer of 0 to 1. From the viewpoint of increasing the tin content, it is preferable that s2 is 0. From the viewpoints of thermal fluidity and embedability, it is preferable that s2 is 1 because an organic chain is preferably included. When s2 is 0, it means that the carbonyl group is singly bonded.)

[0067] Specific examples of (T-2) including W2 include, but are not limited to, the following formulas. (In the following formulas, R, R w represent the same groups as above.)

Chemical formula

[0068] In the general formulas (W1-1) to (W1-4) and (W2-1) to (W2-4) above, R W is a divalent organic group having 1 to 23 carbon atoms. Preferred structures of R W include, but are not limited to, the following structures (* each represents a bonding portion with the carbon atom of the carbonyl group).

Chemical formula

[0069] Furthermore, in the general formulas (W1-1) to (W1-4) and (W2-1) to (W2-4), R W is preferably an unsaturated hydrocarbon having 2 to 23 carbon atoms.)

[0070] A compound for forming a metal-containing film having such a structure can further improve the thermosetting property.

[0071] In the general formulas (W1-1) to (W1-4) and (W2-1) to (W2-4) above, R W is more preferably a structure represented by the following general formula (1) from the viewpoints of improving the thermosetting property and the tin content. [Chemical formula] (In the above general formula (1), R a , R b and R c are a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms, and Ra and Rb may be bonded to form a cyclic substituent. *1 and *2 each represent a bonding portion with a carbonyl group, but *1 and *2 may be reversed.)

[0072] The carboxylic acid raw material containing the above general formula (1) can be synthesized by ring-opening a cyclic acid anhydride. However, when an asymmetric cyclic anhydrous carboxylic acid is ring-opened, it becomes a mixture of two types, resulting in the bonding form as described above. The presence of such isomers can suppress crystallinity, and an improvement in embedding properties can be expected due to an improvement in solvent solubility and an improvement in thermal fluidity. For example, in the ring-opening reaction between itaconic anhydride derivative shown below and 4-(2-aminoethyl)pyrocatechol, the product is different depending on whether the nucleophilic reaction of the amine occurs at the carbonyl adjacent to the unsaturated methylene group (>C=CH2) or at the carbonyl adjacent to the saturated methylene group (>CH2), resulting in a mixture of two isomers. [Chemical formula]

[0073] The compound represented by the above general formula (M) can be synthesized by condensing a carboxylic acid unit (T) containing tin, an alkyltin trichloride, a dialkyltin dichloride, or a dialkyltin oxide (Z), and a monovalent carboxylic acid (P) when contained (Reactions 1 to 4). (R, R1, R2, R3, m, s1, s2, W1, and W2 are the same as described above.)

[0074] (Reaction 1) When 3 equivalents of (T) are added to alkyltin trichloride (Z) and condensed.

Chemical formula

[0075] (Reaction 2) When 2 equivalents of (T) are added to dialkyltin dichloride (Z) and condensed.

Chemical formula

[0076] (Reaction 3) When 1 equivalent each of (T) and (P) are added to dialkyltin oxide (Z) and condensed.

Chemical formula

[0077] (Reaction 4) When 2 equivalents of (T) and 1 equivalent of (P) are added to alkyltin trichloride (Z) and condensed.

Chemical formula

[0078] Also, when synthesizing using multiple types of (T) or when using not only (T) but also (P) in the reaction, there are cases where all (T) in one molecule are the same type of (T) (M) or all are different types of (T) (M). Therefore, n1 and n2 indicate the existence ratio of those substituents in the reaction system. For example, when using alkyltin trichloride (1 equivalent) as (Z), acrylic acid (1 equivalent) as (P), and the following raw material (2 equivalents) as (T), there are molecules where all are derived from (T) or where (T):(P) = 2:1, and overall, it means the existence ratio is like the charging ratio.

Chemical formula

[0079] In the general formula (M) above, the compound of the unit represented by (T) can be synthesized by condensing one equivalent each of a compound (X) containing both a hydroxyl group (two hydroxyl groups adjacent to each other through two carbon atoms) and a carboxylic acid adjacent to a tin compound such as dialkyltin dichloride or dialkyltin oxide (Z) (Reactions A1, A2). (R1, R2, R3, m, s1, s2, W1, and W2 are the same as described above.)

[0080] (Reaction A1) General formula for the condensation of dialkyltin oxide (Z) and catechol derivative (X)

Chemical formula

[0081] (Reaction A2) General formula for the condensation of dialkyltin dichloride (Z) and diol derivative (X) (s3 = 1)

Chemical formula

[0082] The condensation reactions (Reactions 1 to 4) using the above (T), (Z), and (P), and the condensation reactions (Reaction A (Reactions A1 and A2)) using (X) and (Z) can generally be carried out without a solvent or in a solvent at room temperature or, if necessary, under cooling or heating. Examples of the solvents used include ethers such as diethyl ether, dibutyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, tetrahydrofuran, and 1,4-dioxane; chlorinated solvents such as methylene chloride, chloroform, dichloroethane, and trichloroethylene; hydrocarbons such as hexane, heptane, benzene, toluene, xylene, and cumene; nitriles such as acetonitrile; ketones such as acetone, ethyl methyl ketone, and isobutyl methyl ketone; esters such as ethyl acetate, n-butyl acetate, and propylene glycol methyl ether acetate; lactones such as γ-butyrolactone; and aprotic polar solvents such as dimethyl sulfoxide, N,N-dimethylformamide, N-methyl-2-pyrrolidone, and hexamethylphosphoric triamide. These can be used alone or in admixture of two or more. These solvents can be used in the range of 0 to 3000 parts by mass based on 100 parts by mass of the reaction raw materials. The reaction temperature is preferably from -50°C to about the boiling point of the solvent, more preferably from room temperature to 130°C.

[0083] When a chloro compound is used as (Z), a base catalyst can also be added as a catalyst. As the base catalyst used, inorganic salts such as potassium carbonate and sodium hydroxide can be used, but since it is difficult to remove them, organic bases such as triethylamine, diisopropylethylamine, N,N-dimethylaniline, pyridine, and 4-dimethylaminopyridine are preferably used. The amount used is preferably 1.0 to 1.2 equivalents, more preferably 1.0 to 1.1 equivalents, relative to the chloro groups contained. Here, one equivalent relative to the chloro groups contained means, for example, when dialkyltin dichloride is used as (Z), adding 2.0 moles of the catalyst per 1 mole of dialkyltin dichloride.

[0084] As the condensation reaction method of reaction A, there are methods such as charging (X), (Z), a solvent, and a catalyst all at once, a method of dropping (Z) in the presence of (X), a solvent, and a catalyst, and a method of dropping a catalyst in the presence of (X), (Z), and a solvent. The amount of (Z) used at this time is preferably 0.95 to 1.05 equivalents, more preferably 1.0 equivalent, relative to (X). After the condensation reaction of reaction A is completed, in order to remove unreacted raw materials, catalysts, etc., the temperature of the reaction kettle is raised to 130 to 230 °C, and the volatile components are removed at about 1 to 50 mmHg, or steps such as a method of fractionating impurities and the obtained compound using an appropriate poor solvent and good solvent can also be added. Further, after the completion of reaction A, the above reaction 3 or 4 can be continuously carried out by adding additional (Z) or (P) to the reaction system. After the condensation reaction of reaction 3 or 4 is completed, a step of removing impurities and the like can be added in the same manner as the above purification method.

[0085] In the above general formula (M), P is *-OC(=O)R (R is a monovalent organic group, and * represents the bonding part with the Sn atom). When P is included, since R can be freely changed, if a bulky structure is incorporated, improvement in solubility and thermal fluidity can be expected. Furthermore, since it is also possible to have a crosslinked structure, sublimation products can be suppressed, and suppression of volume shrinkage that induces deterioration of embedability can also be expected. As the carboxylic acid raw material containing R, for example, a linear substituted or unsubstituted hydrocarbon group such as acetic acid, propionic acid, or glycine, a branched substituted or unsubstituted hydrocarbon group such as pivalic acid or 2-aminoisobutyric acid, or a cyclic substituted or unsubstituted hydrocarbon group such as cyclopropanecarboxylic acid or 3,3-difluorocyclobutanecarboxylic acid, etc., there is no particular limitation as long as it is a monofunctional carboxylic acid. From the viewpoint of thermosetting properties, it is more preferably a group containing an unsaturated hydrocarbon group, a group containing a hydroxyl group, a group in which a protecting group is eliminated by heat or an acid, and a hydroxyl group or a carboxyl group is generated.

[0086] Further, it is preferable that the above R is any one of the groups represented by the following general formulas (A-1) to (A-4), the following general formula (3), and the following general formula (4).

Chemical formula

[0087] In the general formulas (A-1) to (A-4), Y A1 , Y A2 may be the same as or different from each other, and is a substituted or unsubstituted divalent organic group having 1 to 23 carbon atoms and being saturated or having 2 to 23 carbon atoms and being unsaturated (preferably a hydrocarbon group), a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, or a substituted or unsubstituted arylalkylene group having 7 to 31 carbon atoms. R A is a hydrogen atom, a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms and being saturated or having 2 to 20 carbon atoms and being unsaturated (such as an aliphatic hydrocarbon group), 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 R A1is an organic group in which a protecting group is eliminated by the action of either or both of the acid and heat represented by the general formula (2) above to generate one or more hydroxyl groups or carboxyl groups, and is preferably (A-4) in consideration of thermal fluidity and solubility, and is preferably (A-1) from the viewpoint of suppressing sublimation due to organic decomposition that increases the tin content.

[0088] In the general formulas (A-1) to (A-4) above, Y A1 and Y A2 Preferred structures thereof include, for example, the following structures, but are not limited thereto. (In the following formulas, * a represents the bonding portion with R A1 and * b represents the other bonding portion.

Chemical formula

[0089] In the general formula (A-3) above, R A is a hydrogen atom, a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms that is saturated or having 2 to 20 carbon atoms that is unsaturated (such as an aliphatic hydrocarbon group), 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 sublimation of the sublimated product and increasing the Sn content.

[0090] In the general formula (2) above, R A2 is an organic group in which a protecting group (thermoacid-labile group) is eliminated by the action of either or both of an acid and heat, and is preferably a tertiary hydrocarbyl group or a group that forms an acetal structure together with an adjacent oxygen atom, and particularly preferably a tertiary hydrocarbyl group.

[0091] The tertiary hydrocarbyl group preferably has 4 to 20 carbon atoms, and a tert-butyl group is particularly preferred from the viewpoints of suppressing sublimation of the thermally decomposed product and ease of raw material procurement. Specific examples include, but are not limited to, those shown below. In the following formulas, * represents a bond to an oxygen atom. [Chemistry]

[0092] [Chemistry]

[0093] [Chemistry]

[0094] [Chemistry]

[0095] Specific examples of the group forming the acetal structure include, but are not limited to, those shown below. In the following formulas, * represents a bond to an oxygen atom. [Chemistry]

[0096] [Chemistry]

[0097] [Chemistry]

[0098] Such a compound for forming a metal-containing film will be a compound for forming a metal-containing film excellent in solvent solubility and thermal fluidity. Also, R A1Since it contains an organic group in which a protecting group is eliminated by the action of either a bulky acid or heat or both in the structure, when it is used in a composition for forming a metal-containing film, they are eliminated during baking, so the tin content increases, and it becomes a compound for forming a metal-containing film excellent in dry etching resistance. Further, the hydroxyl groups and carboxyl groups generated by the elimination easily react with radicals generated by the cleavage of the tin-carbon bond during baking due to the presence of the terminal OH group and α-hydrogen, and a crosslinking reaction occurs, and since it is excellent in thermosetting properties, volume shrinkage can be suppressed, and even after high-temperature baking, a composition for forming a metal-containing film such as a resist underlayer film material excellent in film-forming properties and embedding properties can be provided.

[0099]

Chemical formula

Chemical formula

Chemical formula

[0100] In the above general formula (3), X is a divalent organic group having 1 to 31 carbon atoms, B is the above general formula (B), and * represents the bonding portion with the carbonyl group. In the above general formula (B), Y Bis a divalent organic group having 1 to 20 carbon atoms, which may be substituted or unsubstituted, saturated or unsaturated with 2 to 20 carbon atoms (such as an aliphatic hydrocarbon group), a divalent arylene group having 6 to 30 carbon atoms, which may be substituted or unsubstituted, or a divalent arylalkylene group having 7 to 31 carbon atoms, which may be substituted or unsubstituted, and R B is preferably a hydroxyl group or any of the structures represented by the above general formulas (B-1) to (B-3). 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, and is preferably a hydrogen atom from the viewpoint of suppressing sublimation.

[0101] Examples of the preferable structure of the above general formula (B) include, but are not limited to, the following structures. In the following formulas, * represents a bond to a carbonyl group.

Chemical formula

[0102] If it is such a compound for forming a metal-containing film, it will be a compound for forming a metal-containing film excellent in solvent solubility and thermal fluidity. Further, since R B contains a hydroxyl group or an unsaturated bond therein, when it is used in a composition for forming a metal-containing film, they cause a crosslinking reaction during baking, so it is excellent in thermosetting. Furthermore, by reacting with radicals generated by the cleavage of the tin-carbon bond, the crosslinking reaction is promoted, and since it is excellent in thermosetting, volume shrinkage can be suppressed, and even after high-temperature baking, a composition for forming a metal-containing film excellent in film-forming property and embedding property can be provided.

[0103]

Chemical formula

Chemical formula

[0104] In the above general formula (4), X is a divalent organic group having 1 to 31 carbon atoms. Specifically, examples include a substituted or unsubstituted divalent hydrocarbon group having 1 to 20 carbon atoms that is saturated or has 2 to 20 carbon atoms and is unsaturated, 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 a group represented by the above general formulas (C-1) to (C-4). In (C-1) and (C-3), R C1 is preferably a methyl group from the viewpoint of thermal fluidity and preferably a hydrogen atom from the viewpoint of curability. Also, R in (C-3) and (C-4) C2 is preferably a structure described above other than a hydrogen atom from the viewpoint of thermal fluidity.

[0105] In the above general formulas (C-1) to (C-4), R C2 As a preferable structure, for example, the following structures can be given, but are not limited thereto. In the following formulas, * represents a bond with a nitrogen atom. [Chemical formula]

[0106] For a metal-containing film-forming compound having such a structure, since it contains an organic group represented by the above general formula (3), it becomes a metal-containing film-forming compound excellent in solvent solubility and heat resistance characteristics. Further, since it contains any one of the structures represented by the above general formulas (C-1) to (C-4) at the terminal, the crosslinking group density is high, and a rapid volume shrinkage during baking can be reduced, so that a metal-containing film-forming composition excellent in film-forming properties and embedding properties can be provided.

[0107] The metal-containing film formed using the composition containing the metal-containing film-forming compound (M) generates radicals while the Sn-C bond dissociates during baking, and the generated radicals cause the curing reaction to proceed (Formula 1). Therefore, since recombination of the radicals is necessary to promote the curing reaction, it takes time for curing or it is necessary to increase the radical generation efficiency at a high temperature. However, since the compound of the present invention contains a plurality of tin atoms in one molecule, there are many active species, and generation and recombination of radicals occur efficiently. Therefore, it is excellent in heat resistance and thermosetting properties, and a resist underlayer film excellent in film-forming properties can be provided. Further, when a group containing an unsaturated bond or a hydroxyl group is present in P, not only do they react with radicals, but also a crosslinking reaction proceeds only with these groups (Formula 2), resulting in a film having more excellent heat resistance and thermosetting properties.

[0108]

Chemical formula

[0109]

Chemical formula

[0110] Y in the above general formulas (A-1) to (A-4) A1 , preferred structures of X in the above general formula (2) or X in the above general formula (3) include, for example, the following structures, but are not limited thereto. In the following formulas, * represents the bonding portion with the carbon atom of the carbonyl group or * in the formulas (A-1) to (A-4), formula (3), and formula (4).

Chemical formula

[0111] Y in the above general formulas (A-1) to (A-4) A1 , X in the above general formula (3), or X in the above general formula (4) is preferably a metal-containing film-forming compound characterized by being an unsaturated hydrocarbon group having 2 to 23 carbon atoms.

[0112] Y in the general formulas (A-1) to (A-4) above A1 If X in the general formula (3) above or X in the general formula (4) above is an unsaturated hydrocarbon group having 2 to 23 carbon atoms, the thermosetting property of the metal-containing film-forming compound can be further improved.

[0113] Further, Y in the general formulas (A-1) to (A-4) above A1 , X in the general formula (3) above, or X in the general formula (4) above, a metal-containing film-forming compound characterized by being the following general formula (1) can be provided. [Chemical formula] (In the general formula (1) above, R a , R b and R c are 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 bonding portion with a carbonyl group, and *1 and *2 may be reversed.)

[0114] The carboxylic acid raw material containing the general formula (1) above can be synthesized by ring-opening an acid anhydride. However, when an asymmetric anhydrous carboxylic acid is ring-opened, a mixture of two types is obtained, resulting in the bonding form as described above. The presence of such isomers can suppress crystallinity, and an improvement in flatness characteristics due to an improvement in solvent solubility and an improvement in thermal fluidity can be expected. [Chemical formula]

[0115] In the general formula (1) above, R a , R b and R c are 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 from the viewpoint of suppressing sublimation, it is particularly preferable that they are hydrogen atoms.

[0116] The ratio Mw / Mn (i.e., dispersity) of the weight-average molecular weight Mw to the number-average molecular weight Mn in terms of polystyrene by gel permeation chromatography (GPC) method using tetrahydrofuran of the compound for forming a metal-containing film is preferably in the range of 1.00 ≦ Mw / Mn ≦ 1.80, and more preferably 1.00 ≦ Mw / Mn ≦ 1.50. By definition, Mw / Mn is 1.00 for a monomolecular compound, but due to the separation property of GPC, the measured value may exceed 1.00. Generally, for a polymer having repeating units, it is extremely difficult to approach Mw / Mn = 1.00 unless a special polymerization method is used, and it has a distribution of Mw and Mw / Mn becomes a value exceeding 1. In the present invention, 1.00 ≦ Mw / Mn ≦ 1.50 is defined as an index indicating monomolecularity to distinguish between a monomolecular compound and a polymer. Note that the above index can also be applied to a mixture of two or more kinds of compounds for forming a metal-containing film.

[0117] <Composition for forming a metal-containing film> Further, the present invention can provide a composition for forming a metal-containing film that functions as a resist underlayer film material used in semiconductor manufacturing, which contains the above (a) compound for forming a metal-containing film and (b) an organic solvent.

[0118] For such a composition for forming a metal-containing film, since it contains an organotin compound excellent in heat resistance and thermal fluidity, it has excellent dry etching resistance against conventional organic underlayer film materials and can form a metal-containing film such as a resist underlayer film having high embedding / planarization characteristics.

[0119] 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.

[0120] <(b) Organic solvent> As the (b) organic solvent that can be used in the composition for forming a metal-containing film of the present invention, any organic solvent in which the above-mentioned (a) compound for forming a metal-containing film, (c) crosslinking agent, (d) surfactant, (e) fluidity promoter, (f) acid generator, and other additives can be dissolved or dispersed may be used, and there is no particular limitation.

[0121] Specifically, the organic solvents described in paragraphs

[0091] to

[0092] of JP-A No. 2007-199653 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, and γ-butyrolactone, or a mixture containing one or more of these is preferably used.

[0122] (High-boiling solvent) In the composition for forming a resist underlayer film, the (b) organic solvent may be used as a mixture of one or more organic solvents having a boiling point (the value at 1 atmospheric pressure (1013 hPa)) of less than 180°C and one or more organic solvents having a boiling point of 180°C or higher (high-boiling solvents).

[0123] As the high-boiling solvent, there are no particular restrictions as long as it can dissolve each component of the composition for forming a metal-containing film of the present invention, and examples include hydrocarbons, alcohols, ketones, esters, ethers, chlorinated solvents, etc. Specific examples include 1-octanol, 2-ethylhexanol, 1-nonanol, 1-decanol, 1-undecanol, ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,5-hexanediol, 2,4-heptanediol, 2-ethyl-1,3 - hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, glycerin, n - nonyl acetate, monohexyl ether, ethylene glycol mono - 2 - ethylhexyl ether, ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, diethylene glycol monoethyl ether, diethylene glycol monoisopropyl ether, diethylene glycol mono - n - butyl ether, diethylene glycol monoisobutyl ether, diethylene glycol monohexyl ether, diethylene glycol monophenyl ether, diethylene glycol monobenzyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol monomethyl ether, triethylene glycol - n - butyl ether, triethylene glycol butyl methyl ether, tetraethylene glycol dimethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol mono - n - propyl ether, dipropylene glycol mono - n - butyl ether, tripropylene glycol dimethyl ether, tripropylene glycol monomethyl ether, tripropylene glycol mono - n - propyl ether, tripropylene glycol mono - n - butyl ether, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, triacetin, propylene glycol diacetate, dipropylene glycol methyl - n - propyl ether, dipropylene glycol methyl ether acetate, 1,4 - butanediol diacetate, 1,3 - butylene glycol diacetate, 1,Examples thereof include 6 - hexanediol diacetate, triethylene glycol diacetate, γ - butyrolactone, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, dihexyl malonate, diethyl succinate, dipropyl succinate, dibutyl succinate, dihexyl succinate, dimethyl adipate, diethyl adipate, dibutyl adipate, etc., and these may be used alone or in combination.

[0124] The high - boiling - point solvent may be appropriately selected from the above - mentioned ones according to the temperature for heat - treating the above - mentioned resist underlayer film - forming composition, etc. The boiling point of the high - boiling - point solvent is preferably 180°C to 300°C, and more preferably 200°C to 300°C. With such a boiling point, there is no fear that the volatilization during baking (heat - treatment) will be too fast, so sufficient thermal fluidity can be obtained during film formation, and it is considered that a resist underlayer film with excellent embedding / planarization characteristics can be formed. Also, with such a boiling point, it will not remain in the film without volatilizing after baking, so there is no fear of adversely affecting the film physical properties such as etching resistance.

[0125] The blending amount of the organic solvent is preferably in the range of 200 to 10,000 parts, more preferably 250 to 5,000 parts, with respect to 100 parts by mass of the metal - containing film - forming compound (a).

[0126] Also, when using a high - boiling - point solvent, the blending amount is preferably 1 to 30 parts by mass with respect to 100 parts by mass of the organic solvent having a boiling point of less than 180°C. With such a blending amount, sufficient thermal fluidity can be imparted during baking, and it does not remain in the film and does not lead to deterioration of film physical properties such as etching resistance, so it is preferable.

[0127] <Resist underlayer film - forming composition> The above - mentioned composition is a composition for forming a metal - containing film that can be used as a resist underlayer film for the multilayer resist method, and can be made into a resist underlayer film - forming composition containing at least one of (c) a cross - linking agent, (d) a surfactant, (e) a fluidity promoter, and (f) an acid generator. Hereinafter, the components contained in the composition for forming the resist underlayer film other than the compound for forming the metal-containing film (a) and the organic solvent will be described.

[0128] [(c) Crosslinking agent] The composition for forming the resist underlayer film may further contain (c) a crosslinking agent in order to enhance the film density and further suppress the intermixing with the resist upper layer film. The crosslinking agent is not particularly limited, and various known types of crosslinking agents can be widely used. As an example, 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 (for example, methylol or alkoxymethyl type crosslinking agents of polynuclear phenols), epoxy-based crosslinking agents, and oxetane-based crosslinking agents can be exemplified. 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 compound for forming the metal-containing film (a).

[0129] Specific examples of the melamine-based crosslinking agent include hexamethoxymethylated melamine, hexabutoxymethylated melamine, their alkoxy and / or hydroxy-substituted products, and their partial self-condensates. Specific examples of the acrylate-based crosslinking agent include dipentaerythritol hexaacrylate. Specific examples of the glycoluril-based crosslinking agent include tetramethoxymethylated glycoluril, tetrabutoxymethylated glycoluril, their alkoxy and / or hydroxy-substituted products, and their partial self-condensates. Specific examples of the benzoguanamine-based crosslinking agent include tetramethoxymethylated benzoguanamine, tetrabutoxymethylated benzoguanamine, their alkoxy and / or hydroxy-substituted products, and their partial self-condensates. As the urea-based crosslinking agent, specifically, dimethoxymethylated dimethoxyethyleneurea, its alkoxy and / or hydroxy-substituted products, and their partial self-condensates can be exemplified. As the β-hydroxyalkylamide-based crosslinking agent, specifically, N,N,N’,N’-tetra(2-hydroxyethyl) adipic acid amide can be exemplified. As the isocyanurate-based crosslinking agent, specifically, triglycidyl isocyanurate and triallyl isocyanurate can be exemplified. As the aziridine-based crosslinking agent, specifically, 4,4’-bis(ethyleneiminocarbonylamino) diphenylmethane and 2,2-bishydroxymethylbutanol-tris[3-(1-aziridinyl) propionate] can be exemplified. As the oxazoline-based crosslinking agent, specifically, 2,2’-isopropylidene bis(4-benzyl-2-oxazoline), 2,2’-isopropylidene bis(4-phenyl-2-oxazoline), 2,2’-isopropylidene bis(4-phenyl-2-oxazoline), 2,2’-methylene bis-4,5-diphenyl-2-oxazoline, 2,2’-methylene bis-4-phenyl-2-oxazoline, 2,2’-methylene bis-4-tert butyl-2-oxazoline, 2,2’-bis(2-oxazoline), 1,3-phenylene bis(2-oxazoline), 1,4-phenylene bis(2-oxazoline), and 2-isopropenyl oxazoline copolymer can be exemplified.

[0130] As the polynuclear phenol-based crosslinking agent, specifically, the compound represented by the following general formula (XL-1) can be exemplified.

Chemical formula

[0131] S is a single bond or an s-valent hydrocarbon group having 1 to 20 carbon atoms. s is an integer of 1 to 5, and 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. R4 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 methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, pentyl group, isopentyl group, hexyl group, octyl group, ethylhexyl group, decyl group, and eicosanyl group, and a hydrogen atom or a methyl group is preferred.

[0132] As examples of the compound represented by the general formula (XL-1), specifically, the following compounds can be exemplified. Among them, from the viewpoints of improving the curability and film thickness uniformity of the organic film, hexamethoxymethylated products of triphenolmethane, triphenolethane, 1,1,1-tris(4-hydroxyphenyl)ethane, and tris(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene are preferred. R6 below is the same as R4 above. [Chemical formula]

[0133] [Chemical formula]

[0134] Examples of the epoxy-based crosslinking agent and oxetane-based crosslinking agent include monomer type and polymer type. Specific examples of the monomer type include those shown below, but are not limited thereto. [Chemical formula]

[0135] Although the above compounds can be purchased, epoxy crosslinking agents and oxetane crosslinking agents can also be obtained by reacting a hydroxyl group with epibromohydrin, 3-bromomethyloxetane, etc. as shown in the following formula. In the following formula, R5 is a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms in a saturated form or 2 to 20 carbon atoms in an unsaturated form, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted arylalkyl group having 7 to 31 carbon atoms. Also, it is possible to leave some hydroxyl groups unreacted. At this time, it is preferable that the number of epoxy + oxetane > the number of hydroxyl groups, and more preferably the number of epoxy + oxetane > the number of hydroxyl groups × 2. Also, the content of these compounds is preferably 5 to 50 parts by mass, and more preferably 10 to 40 parts by mass, based on 100 parts by mass of the compound for forming a metal-containing film in (a) above.

Chemical formula

[0136] Specific examples of the compound having a hydroxyl group that can be used in the above reaction include, but are not limited to, the following.

Chemical formula

[0137] As the polymer type, specifically, polymers in which the molar fraction of the repeating units represented by the following general formulas (XL-2) and (XL-3) is 20% or more can be mentioned. When the total molar fraction of the structural units represented by the general formulas (XL-2) and (XL-3) does not reach 100%, as other structural units, other acrylic acid esters, other methacrylic acid esters, other acrylamides, other methacrylamides, crotonic acid esters, maleic acid esters, itaconic acid esters and other α,β-unsaturated carboxylic acid esters; α,β-unsaturated carboxylic acids such as methacrylic acid, acrylic acid, maleic acid, 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 dodecene derivatives and other cyclic olefins; α,β-unsaturated carboxylic acid anhydrides such as maleic anhydride, itaconic anhydride; allyl ethers; vinyl ethers; vinyl esters; any structural units derived from vinyl silanes can be used in combination. Further, these polymers preferably have a weight average molecular weight of 1,000 to 20,000 and a GPC dispersity (Mw / Mn) of 2.0 or less. Further, the content of these compounds is preferably 5 to 50 parts by mass, more preferably 10 to 40 parts by mass, based on 100 parts by mass of the compound for forming the metal-containing film (A). In addition, as the molecular weight and dispersity, the weight average molecular weight (Mw) and number average molecular weight (Mn) in terms of polystyrene by GPC using tetrahydrofuran as an eluent may be determined, and the dispersity (Mw / Mn) may be determined.

[0138] [Chemical formula] (In the formula, R7 is a hydrogen atom or a methyl group, R8 is a hydrogen atom or a group selected from the following formulas (2-1) to (2-3), and L1 represents a single bond, -C(=O)O-, -C(=O)NH- or a divalent organic group containing -C(=O)NCH3-.)

[0139] In the general formula (XL-2) above, R7 preferably has the number of groups of (2-1) to (2-3) > the number of hydrogen atoms from the viewpoint of curability, and more preferably, the number of groups of (2-1) to (2-3) > 2 times the number of hydrogen atoms.

Chemical formula

Chemical formula

[0140] <(d) Surfactant> To the composition for forming a resist underlayer film, a (d) surfactant can be added to improve the coatability in spin coating. As the surfactant, for example, those described in

[0142] to

[0147] in JP-A-2009-269953 can be used. When adding the surfactant, the addition amount 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 (a) compound for forming a metal-containing film.

[0141] <(e) Fluidity promoter> Also, the composition for forming a resist underlayer film can further blend another compound or polymer. The fluidity promoter is mixed with the compound for forming a metal-containing film of the present invention and has the role of improving the film-forming property of spin coating and the embedding property on a substrate having a step. Also, as the fluidity promoter, a material having a high carbon atom density and high etching resistance is preferable.

[0142] 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-fluorene-9-ylidene)bisphenol, 2,2'-dimethyl-4,4'-(9H-fluorene-9-ylidene)bisphenol, 2,2'-diallyl-4,4'-(9H-fluorene-9-ylidene)bisphenol, 2,2'-difluoro-4,4'-(9H-fluorene-9-ylidene)bisphenol, 2,2'-diphenyl-4,4'-(9H-fluorene-9-ylidene)bisphenol, 2,2'-dimethoxy-4,4'-(9H-fluorene-9-ylidene)bisphenol, 2,3,2',3'-tetrahydro-(1,1')-spirobiinden-6,6'-diol, 3,3,3',3'-tetramethyl-2,3,2',3'-tetrahydro-(1,1')-spirobiinden-6,6'-diol, 3,3,3',3',4,4'-hexamethyl-2,3,2',3'-tetrahydro-(1,1')-spirobiinden-6,6'-diol, 2,3,2',3'-tetrahydro-(1,1')-spirobiinden-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, and dihydroxynaphthalenes such as 1,5-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, methyl 3-hydroxynaphthalene-2-carboxylate, indene, hydroxyindene, benzofuran, hydroxyanthracene, acenaphthylene, biphenyl, bisphenol, trisphenol, dicyclopentadiene, tetrahydroindene, 4-vinylcyclohexene, norbornadiene, 5-vinylnorborn-2-ene, α-pinene, β-pinene, limonene, etc. novolak resins, polyhydroxystyrene, polystyrene, polyvinylnaphthalene, polyvinylanthracene, polyvinylcarbazole, polyindene, polyacenaphthylene, polynorbornene, polycyclodecene, polytetracyclododecene, polynortricyclene, poly(meth)acrylate, and copolymers thereof. Further, a naphthol dicyclopentadiene copolymer described in JP-A-2004-205685, a fluorene bisphenol novolak resin described in JP-A-2005-128509, an acenaphthylene copolymer described in JP-A-2005-250434, a fullerene having a phenol group described in JP-A-2006-227391, a bisphenol compound and its novolak resin described in JP-A-2006-293298, a novolak resin of an adamantane phenol compound described in JP-A-2006-285095, a bisnaphthol compound and its novolak resin described in JP-A-2010-122656, a fluorene compound described in JP-A-2017-119671, a fullerene resin compound described in JP-A-2008-158002, etc. can also be blended. The blending amount of the above fluidity 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 metal-containing film-forming compound of the present invention.,

[0143] In addition, in the composition for forming a resist underlayer film, as an additive for imparting embedding / planarization characteristics, for example, polyethylene glycol, a liquid additive having a polypropylene glycol structure, or a thermal 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 thermal decomposable polymer preferably contains a repeating unit having an acetal structure represented by the following general formulas (DP1) and (DP1a).

[0144]

Chemical formula

[0145]

Chemical formula

[0146] <(f) Acid generator> In order to further promote the desorption reaction, a (f) acid generator can be added to the composition for forming a resist underlayer film. There are (f) acid generators that generate acid by thermal decomposition and those that generate acid by light irradiation, and any of them can be added. Specifically, the materials described in paragraphs

[0061] to

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

[0147] The above acid generator can be used alone or in combination of two or more. When adding the acid generator, the addition amount is preferably 0.05 to 50 parts by mass, more preferably 0.1 to 10 parts by mass, based on 100 parts by mass of the compound for forming the metal-containing film described in (a) above.

[0148] <Method for forming resist underlayer film> In the present invention, there is provided a method for forming a filling film that functions as a resist underlayer film of a multilayer resist film used in lithography or a planarization film for semiconductor manufacturing, using the above-described composition for forming a metal-containing film.

[0149] In the method for forming a resist underlayer film using the composition for forming a metal-containing film of the present invention, the above-described composition for forming a metal-containing film is coated on a substrate to be processed by a spin coating method or the like. By using a spin coating method or the like, good embedding characteristics can be obtained. After spin coating, the solvent is evaporated, and baking (heat treatment) is performed to promote the crosslinking reaction in order to prevent mixing with the resist upper layer film and the resist intermediate film. The baking is preferably performed in the range of 100°C or higher and 600°C or lower, for 10 to 600 seconds, more preferably in the range of 200°C or higher and 500°C or lower, for 10 to 300 seconds. Considering the influence on device damage and wafer deformation, the upper limit of the heating temperature in the wafer process of lithography is preferably 600°C or lower, more preferably 500°C or lower.

[0150] Also, 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 of the present invention is coated on a substrate to be processed by the spin coating method or the like as described above, and the composition for forming a metal-containing film is fired and cured in an atmosphere with an oxygen concentration of 0.1% by volume or more and 21% by volume or less to form a metal-containing film.

[0151] By firing the composition for forming a metal-containing film of the present invention in such an oxygen atmosphere, a sufficiently cured film can be obtained. The atmosphere during baking may be air, but it is preferable to enclose an inert gas such as N2, Ar, or He to reduce oxygen in order to prevent oxidation of the metal-containing film. In order to prevent oxidation, it is necessary to control the oxygen concentration, preferably 1000 ppm or less, more preferably 100 ppm or less (by volume). Preventing oxidation of the metal-containing film during baking is preferable because it does not cause an increase in absorption or a decrease in etching resistance.

[0152] <Pattern formation method using a composition for forming a resist underlayer film> Further, in the present invention, as a pattern formation method by a two-layer resist process using the above composition for forming a metal-containing film, a metal-containing film is formed on a substrate to be processed using the above composition for forming a metal-containing film, and a resist upper layer film is formed on the metal-containing film using a photoresist material. After the resist upper layer film is pattern-exposed, it is developed with a developer to form a pattern in the resist upper layer film. Using the resist upper layer film in which the pattern is formed as a mask, the pattern is transferred to the metal-containing film by dry etching, and the substrate to be processed is processed using the metal-containing film in which the pattern is formed as a mask to form a pattern on the substrate to be processed. A pattern formation method is provided.

[0153] Since the resist upper layer film of the above two-layer resist process exhibits etching resistance to chlorine-based gases, in the above two-layer resist process, it is preferable to perform dry etching of the metal-containing film using the resist upper layer film as a mask using an etching gas mainly composed of a chlorine-based gas.

[0154] In the present invention, as a pattern formation method by a three-layer resist process using such a composition for forming a metal-containing film, a metal-containing film is formed on a substrate to be processed using the composition for forming a metal-containing film, a resist intermediate film (silicon-containing resist intermediate film) is formed on the metal-containing film using a resist intermediate film material such as a silicon-containing resist intermediate film, a resist upper layer film is formed on the resist intermediate 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, the resist intermediate film is pattern-transferred by dry etching using the resist upper layer film with the pattern formed thereon as a mask, the metal-containing film is pattern-transferred by dry etching using the resist intermediate film with the pattern transferred thereon as a mask, and the substrate to be processed is processed using the metal-containing film with the pattern formed thereon as a mask to form a pattern in the substrate to be processed. A pattern formation method is provided. Hereinafter, the case where a silicon-containing resist intermediate film is used as the resist intermediate film will be described as an example.

[0155] An example of the three-layer resist process will be specifically described with reference to FIG. 1 as follows. In the case of the three-layer resist process, as shown in FIG. 1(A), after forming a metal-containing film (metal-containing resist lower layer film) 3 on a processed layer 2 laminated on a substrate to be processed 1 using the composition for forming a metal-containing film of the present invention, a silicon-containing resist intermediate film 4 is formed, and a resist upper layer film 5 is formed thereon.

[0156] Next, as shown in FIG. 1(B), the required portion (exposed portion) 6 of the upper resist film 5 is exposed, and PEB and development are performed to form an upper resist film pattern 5a (FIG. 1(C)). Using this obtained upper resist 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 upper resist 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 lower layer film pattern) 3a (FIG. 1(E)). Further, after removing the silicon-containing resist intermediate film pattern 4a, the layer to be processed 2 is etched using the metal-containing film pattern 3a as a mask to form a pattern 2a in the layer to be processed (FIG. 1(F)).

[0157] Since the silicon-containing resist intermediate film in the above three-layer resist process exhibits etching resistance to chlorine-based gases and hydrogen-based gases, in the above three-layer resist process, it is preferable to perform dry etching of the metal-containing film using the silicon-containing resist intermediate film as a mask and using an etching gas mainly composed of a chlorine-based gas or a hydrogen-based gas.

[0158] As the silicon-containing resist intermediate film in the above three-layer resist process, a polysiloxane-based intermediate film is also preferably used. By providing an antireflection effect to the silicon-containing resist intermediate film, reflection can be suppressed. In particular, for 193 nm exposure, when a material with a high etching selectivity with respect to the substrate and containing many aromatic groups as an organic film is used, the k value becomes high and the substrate reflection becomes high. However, by providing absorption such that the k value becomes appropriate as the silicon-containing resist intermediate film, it becomes possible to suppress reflection and reduce the substrate reflection to 0.5% or less. As the silicon-containing resist intermediate film having an antireflection effect, polysiloxane having an anthracene for 248 nm and 157 nm exposure and a phenyl group or an absorptive group having a silicon-silicon bond pendant and crosslinking with an acid or heat for 193 nm exposure is preferably used.

[0159] In addition, in the present invention, as a method for forming a pattern by a four-layer resist process using such a composition for forming a metal-containing film, a metal-containing film is formed on a substrate to be processed using the composition for forming a metal-containing film, a silicon-containing resist intermediate film is formed on the resist lower layer film using a silicon-containing resist intermediate film material, an organic antireflection film (BARC) or an adhesion film is formed on the silicon-containing resist intermediate film, a resist upper layer film is formed on the BARC using a photoresist material, after the resist upper layer film is pattern-exposed, it is developed with a developer to form a pattern in the resist upper layer film, using the resist upper layer film in which the pattern is formed as a mask, the pattern is transferred to the BARC or the adhesion film and the silicon-containing resist intermediate film by dry etching, using the silicon-containing resist intermediate film in which the pattern is transferred as a mask, the pattern is transferred to the metal-containing film by dry etching, and using the metal-containing film in which the pattern is formed as a mask, the substrate to be processed is processed to form a pattern on the substrate to be processed, thereby providing a pattern forming method.

[0160] Alternatively, an inorganic hard mask may be formed instead of the silicon-containing resist lower layer film. In this case, at least, a metal-containing film is formed on the object to be processed using the composition for forming a metal-containing film 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, a circuit pattern is formed in the resist upper layer film, the inorganic hard mask is etched using the resist upper layer film in which the pattern is formed as a mask, the metal-containing film is etched using the inorganic hard mask in which the pattern is formed as a mask, and further, the object to be processed is etched using the metal-containing film in which the pattern is formed as a mask to form a pattern on the object to be processed, whereby a semiconductor device circuit pattern can be formed on the substrate.

[0161] As described above, when forming an inorganic hard mask on a metal-containing film, a silicon oxide film, a silicon nitride film, and a silicon oxynitride film (SiON film) can be formed by a CVD method, an ALD method, or the like. For example, as a method for forming a silicon nitride film, it is described in JP-A-2002-334869 and WO 2004 / 066377. The film thickness of the inorganic hard mask is preferably 5 to 200 nm, more preferably 10 to 100 nm. Further, as the inorganic hard mask, a SiON film having a high effect as an antireflection film is most preferably used. 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 composition for forming a metal-containing film used in the present invention has high heat resistance and can withstand a high temperature of 300°C to 500°C. Therefore, a combination of an inorganic hard mask formed by a CVD method or an ALD method and a metal-containing film formed by a spin coating method is possible.

[0162] As described above, a photoresist film may be formed as an upper resist film on the inorganic hard mask. However, an organic antireflection film (BARC) or an adhesion film may be spin-coated on the inorganic hard mask, and a photoresist film may be formed thereon. In particular, when a SiON film is used as the inorganic hard mask, it is possible to suppress reflection even in immersion lithography with a high NA exceeding 1.0 by a two-layer antireflection film of the SiON film and BARC. Another merit of forming BARC is that it has an effect of reducing the pull-off of the photoresist pattern directly above the SiON film.

[0163] In addition, in the present invention, as a pattern formation method by a multilayer resist process using such a composition for forming a metal-containing film, a resist underlayer film is formed on a substrate to be processed, and after applying the composition for forming a metal-containing film of the present invention on the resist underlayer and performing heat treatment to form a metal-containing film, a resist upper layer film is formed on the metal-containing film using a photoresist material. After pattern exposure of the resist upper layer film, development is performed with a developer to form a pattern in the resist upper layer film. Using the resist upper layer film having the pattern formed thereon as a mask, a pattern is transferred to the metal-containing film by dry etching. Using the metal-containing film having the pattern transferred thereon as a mask, a pattern is transferred to the resist underlayer film by dry etching. Further, using the resist underlayer film having the pattern formed thereon as a mask, the substrate to be processed is processed to form a pattern in the substrate to be processed, whereby a semiconductor device circuit pattern can be formed on the substrate.

[0164] As described above, a photoresist film may be formed as the resist upper layer film on the metal-containing film, or an organic adhesion film may be formed by spin coating on the metal-containing film, and a photoresist film may be formed thereon. In this case, a pattern can be transferred to the organic adhesion film and the metal-containing film by dry etching.

[0165] As described above, when forming a resist underlayer film on a substrate to be processed, a resist underlayer film can be formed by a method using a coating-type organic underlayer film material, a CVD method, an ALD method, or the like. Examples of the coating-type organic underlayer film material include resins and compositions disclosed in JP-A-2012-001687, JP-A-2012-077295, JP-A-2004-264710, JP-A-2005-043471, JP-A-2005-250434, JP-A-2007-293294, JP-A-2008-065303, JP-A-2004-205685, JP-A-2007-171895, JP-A-2009-014816, JP-A-2007-199653, JP-A-2008-274250, JP-A-2010-122656, JP-A-2012-214720, JP-A-2014-029435, WO2012 / 077640, WO2010 / 147155, WO2012 / 077640, WO2010 / 147155, WO2012 / 176767, 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.

[0166] The resist upper layer film in the above multilayer resist process may be either positive or negative, and the same photo resist composition as that commonly used can be used. After spin-coating the photo resist composition, pre-baking is performed, and a range of 60 to 180 °C for 10 to 300 seconds is preferable. Thereafter, exposure is performed according to a conventional method, and further, post-exposure baking (PEB) and development are performed to obtain a resist pattern. Note that the thickness of the resist upper layer film is not particularly limited, but a thickness of 30 to 500 nm is preferable, and particularly 50 to 400 nm is preferable.

[0167] As the exposure light, high-energy rays with a wavelength of 300 nm or less can be mentioned, specifically, excimer lasers of 248 nm, 193 nm, 157 nm, soft X-rays of 3 to 20 nm, electron beams, X-rays, and the like.

[0168] As the method for forming the pattern on the resist upper layer film, it is preferable to form a pattern by photolithography with a wavelength of 5 nm or more and 300 nm or less, direct drawing by an electron beam, nanoimprinting, or a combination thereof.

[0169] Also, as the development method in the pattern formation method, it is preferable to perform development with an alkali or an organic solvent.

[0170] Next, etching is performed using the obtained resist pattern as a mask. For the etching of the silicon-containing resist intermediate film and the inorganic hard mask in the three-layer resist process, an upper layer resist pattern is used as a mask and performed using a fluorocarbon-based gas. Thereby, a silicon-containing resist intermediate film pattern and an inorganic hard mask pattern are formed.

[0171] Next, using the obtained silicon-containing resist intermediate film pattern or inorganic hard mask pattern as a mask, etching of the metal-containing film is performed. The etching of the metal-containing film is preferably performed using an etching gas mainly composed of a chlorine-based gas.

[0172] The etching of the next workpiece can also be performed by a conventional method. For example, if the workpiece is SiO2, SiN, or a silica-based low dielectric constant insulating film, etching mainly using a fluorocarbon-based gas is performed. When the substrate processing is etched with a fluorocarbon-based gas, the silicon-containing resist intermediate film pattern in the three-layer resist process is peeled off simultaneously with the substrate processing.

[0173] The metal-containing film obtained by the composition for forming a metal-containing film of the present invention is characterized by excellent etching resistance during the etching of these workpieces.

[0174] The workpiece (workpiece substrate) is not particularly limited, and substrates such as Si, α-Si, p-Si, SiO2, SiN, SiON, W, TiN, Al, etc., or those with a processed layer formed on the substrate are used. As the processed layer, various Low-k films such as Si, SiO2, SiON, SiN, p-Si, α-Si, W, W-Si, Al, Cu, Al-Si, etc., and their stopper films are used, and can usually be formed with a thickness of 50 to 10,000 nm, particularly 100 to 5,000 nm. When forming the processed layer, the substrate and the processed layer are made of different materials.

[0175] In the pattern formation method using the composition for forming a metal-containing film of the present invention, it is preferable to use a workpiece substrate having a structure or step with a height of 30 nm or more. As described above, since the composition for forming a metal-containing film of the present invention has excellent embedding / planarization characteristics, even if the workpiece substrate has a structure or step (concavo-convex) with a height of 30 nm or more, a flat cured film can be formed. The height of the structure or step of the workpiece substrate is preferably 30 nm or more, more preferably 50 nm or more, and even more preferably 100 nm or more. In the method of processing a stepped substrate having the above height pattern, by forming the composition for forming a metal-containing film of the present invention and performing embedding / planarization, it becomes possible to make the film thicknesses of the resist intermediate film and the resist upper layer film formed thereafter uniform, so it becomes easy to secure the exposure depth margin (DOF) during photolithography, which is very preferable.

[0176] <Tone inversion type pattern formation method using a composition for forming a metal-containing film> In the present invention, as a tone inversion type pattern forming method using such a composition for forming a metal-containing film, a resist underlayer film is formed on a substrate to be processed, and 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 is formed on the resist underlayer film. A resist upper layer film is formed on the resist intermediate film, or the combination of the inorganic hard mask intermediate film and the organic thin film using a photoresist material. After pattern exposure of the resist upper layer film, the resist upper layer film is developed with a developer to form a pattern on the resist upper layer film. Using the resist upper layer film on which the pattern is formed as a mask, the pattern is transferred to the resist intermediate film, or the organic thin film and the inorganic hard mask intermediate film by dry etching. Using the resist intermediate film or the inorganic hard mask intermediate film on which the pattern is transferred as a mask, the pattern is transferred to the resist underlayer film by dry etching. A metal-containing film is coated on the resist underlayer film on which the pattern is formed using the above composition for forming a metal-containing film, and the space between the resist underlayer film patterns is filled with the metal-containing film. The metal-containing film covering the resist underlayer film on which the pattern is formed is etched back by a chemical stripper or dry etching to expose the upper surface of the resist underlayer film on which the pattern is formed. The resist intermediate film or the hard mask intermediate film remaining on the upper surface of the resist underlayer film is removed by dry etching, and the resist underlayer film on which the pattern is formed with the surface exposed is removed by dry etching to form an inverted pattern of the original pattern on the metal-containing film. Using the metal-containing film on which the inverted pattern is formed as a mask, the substrate to be processed is processed to form an inverted pattern on the substrate to be processed. A tone inversion type pattern forming method is provided, which is characterized by having the above steps.

[0177] An example of the formation of a tone inversion type pattern will be specifically described below with reference to FIG. 2. As shown in FIG. 2(G), after forming a resist underlayer film 7 made of a coating type organic underlayer film material on a processed layer 2 laminated on a substrate to be processed 1, a silicon-containing resist intermediate film 4 is formed, and a resist upper layer film 5 is formed thereon.

[0178] Next, as shown in FIG. 2(H), the required 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 this 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 lower layer film 7 made of a coating-type organic lower layer film material is etched with oxygen plasma using this obtained silicon-containing resist intermediate film pattern 4a as a mask to form a resist lower layer film pattern 7a made of a coating-type organic lower layer film material (FIG. 2(K)).

[0179] After applying the composition for forming a metal-containing film of the present invention onto the resist lower layer film pattern 7a made of a coating-type organic lower layer film material and performing heat treatment, the metal-containing film 8 is coated, and the space between the resist lower layer film patterns 7a made of a coating-type organic lower layer film material is filled with the metal-containing film (FIG. 2(L)). Next, the metal-containing film 8 covering the resist lower layer film pattern 7a made of a coating-type organic lower layer film material is etched back by a chemical stripper or dry etching to expose the upper surface of the resist lower layer film pattern 7a made of a coating-type organic lower layer film material (FIG. 2(M)). Further, the silicon-containing resist intermediate film pattern 4a remaining on the upper surface of the resist lower layer film pattern 7a made of a coating-type organic lower layer film material is removed by dry etching (FIG. 2(N)). Next, after removing the resist lower layer film pattern 7a made of a coating-type organic lower layer film material by dry etching and forming an inverted pattern of the original pattern on the metal-containing film (forming a metal-containing film pattern 8a with the resist lower layer film pattern inverted) (FIG. 2(O)), the substrate to be processed is processed using the metal-containing film pattern 8a with the resist lower layer film pattern inverted as a mask to form a tone-inverted pattern on the substrate to be processed (FIG. 2(P)).

[0180] As described above, when forming a resist underlayer film on a substrate to be processed, a resist underlayer film can be formed by a method using a coating-type organic underlayer film material, a CVD method, an ALD method, or the like. Examples of the coating-type organic underlayer film material include resins and compositions disclosed in JP-A-2012-1687, JP-A-2012-77295, JP-A-2004-264710, JP-A-2005-043471, JP-A-2005-250434, JP-A-2007-293294, JP-A-2008-65303, JP-A-2004-205685, JP-A-2007-171895, JP-A-2009-14816, JP-A-2007-199653, JP-A-2008-274250, JP-A-2010-122656, JP-A-2012-214720, JP-A-2014-29435, International Publication WO2012 / 077640, International Publication WO2010 / 147155, International Publication WO2012 / 077640, International Publication WO2010 / 147155, International Publication WO2012 / 176767, 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-2019-44022, and the like.

[0181] In the above tone inversion type pattern forming method, after coating the obtained resist underlayer film pattern with a composition for forming a metal-containing film, it is preferable to remove the metal-containing film using a dry etching gas mainly composed of a chlorine-based gas in order to expose the upper surface of the resist underlayer film pattern. Thereafter, the resist intermediate film or the hard mask intermediate film remaining on the resist underlayer film is removed by dry etching with a fluorocarbon-based gas, and the exposed resist underlayer film pattern on the surface is removed by dry etching with an oxygen-based gas to form a metal-containing film pattern.

[0182] In the above-described tone inversion type pattern formation method, the resist underlayer film pattern preferably has a structure or step with a height of 30 nm or more. As described above, since the composition for forming a metal-containing film of the present invention has excellent embedding / planarization characteristics, even if the film to be processed has a structure or step (concavo-convex) with 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 even more preferably 100 nm or more. In the method of inverting the resist underlayer film pattern having the above-described height pattern, by forming the composition for forming a metal-containing film of the present invention and performing embedding / planarization, it becomes possible to perform pattern inversion / transfer with high precision, which is very preferable. Since it has excellent dry etching resistance using a chlorofluorocarbon gas with respect to a resist underlayer film using a conventional coating type organic underlayer film material, by inverting the resist underlayer film pattern with the above-described composition for forming a metal-containing film, a desired resist pattern can be formed on the film to be processed with high precision.

Example

[0183] Hereinafter, the present invention will be described more specifically by showing synthesis examples, comparative synthesis examples, examples, and comparative examples, but the present invention is not limited thereto. As for the molecular weight and dispersity, the weight average molecular weight (Mw) and number average molecular weight (Mn) in terms of polystyrene obtained by gel permeation chromatography (GPC) using tetrahydrofuran as an eluent were determined, and the dispersity (Mw / Mn) was determined.

[0184] [Synthesis Example] In the following synthesis examples and comparative examples, the tin compounds Sn: (Sn-1) to (Sn-5), raw material group T: (TT1) to (TT14), and raw material group P: (P-1) to (P-6) shown below were used. Each raw material group is shown below. Note that, as described above, isomers exist for the compounds (TT2), (TT3), (TT5), and (P-3) below, but one structure is shown as a representative.

[0185] Tin compound Sn: [Chemistry] (nBu represents a normal butyl group, tBu represents a tert-butyl group, and Oc represents a normal octyl group)

[0186] Raw material group T: [Chemistry]

[0187] Raw material group P: [Chemistry]

[0188] [Synthesis Example 1] Synthesis of the compound (M-1) for forming a metal-containing film (Reaction 1) 5.0 g of a tin compound (Sn-1), 1.9 g of raw material (TT1), and 100 g of toluene were added, and the mixture was reacted for 5 hours while removing water at 130°C. (Reaction 2) After returning to room temperature, an additional 2.5 g of (Sn-1) was added, and the mixture was further reacted for 5 hours while removing water at 130°C. Toluene was removed under reduced pressure, and the resulting product was suspended in methanol, filtered, and washed to obtain the compound (M-1).

[0189] [Synthesis Examples 2 to 8] Synthesis of the compounds (M-2) to (M-8) for forming a metal-containing film The tin compound and raw material T were changed as shown in Table 1, and the same operations as in Synthesis Example 1 were performed to obtain the compounds (M-2) to (M-8) for forming a metal-containing film. [Table 1]

[0190] [Synthesis Example 9] Synthesis of the compound (M-9) for forming a metal-containing film (Reaction 1) 5.0 g of a tin compound (Sn-1), 3.1 g of raw material (TT9), and 100 g of toluene were added, and the mixture was reacted for 5 hours while removing water at 130°C. (Reaction 2) Return to room temperature, additionally add 2.8 g of (Sn-5) and 2.2 g of (P-1), and react at 130 °C for 12 hours. Remove toluene under reduced pressure, suspend in methanol, filter, and wash to obtain compound (M-9).

[0191] [Synthesis Examples 10 to 16] Synthesis of Compounds (M-10) to (M-16) for Forming Metal-Containing Films Change the tin compound and raw material T as shown in Table 2, and perform the same operations as in Synthesis Example 9 to obtain compounds (M-10) to (M-16) for forming metal-containing films.

Table 2

[0192]

Chemical formula

[0193] [Synthesis of Compound (R-1) for Forming Metal-Containing Film for Comparative Example] Add 5.0 g of tin compound (Sn-1), 8.6 g of raw material group P (P-2), and 100 g of toluene, and react at 130 °C for 7 hours while removing water. After the reaction, remove the solvent under reduced pressure to obtain (R-1).

Chemical formula

[0194] [Synthesis of Compound (R-2) for Forming Metal-Containing Film for Comparative Example] Add 5.0 g of tin compound (Sn-1), 6.8 g of raw material group T (TT14), and 50 g of toluene, and react at 130 °C for 7 hours while removing water. After the reaction, remove the solvent under reduced pressure to obtain (R-2).

Chemical formula

[0195] [Weight-Average Molecular Weight and Dispersion Degree] The weight-average molecular weight (Mw) and dispersity (Mw / Mn) of the above compounds (M-1) to (M-16), (R-1) and (R-2) were determined. The results are shown in Table 3. The weight-average molecular weight Mw and number-average molecular weight Mn are values in terms of polystyrene by the GPC method using tetrahydrofuran, and the dispersity was determined therefrom. [Table 3]

[0196] [Synthesis of the compound (R-3) for forming a metal-containing film for comparative example] As a metal-containing compound assumed to be used in a photoresist, the tin compound reported in [Synthesis Example 8] of Japanese Patent No. 702894 was synthesized. 3 g of isopropyltriphenyltin, 1.4 g of succinic acid and 20 ml of acetonitrile were dissolved in acetonitrile and refluxed for 24 hours. After the reaction, the solvent was removed under reduced pressure to obtain a tin-containing compound (R-3). [Chemical formula]

[0197] [Synthesis of the compound (R-4) for forming a metal-containing film for comparative example] 10 g of catechol, 6.6 g of formaldehyde, and 30 g of PGME (propylene glycol monomethyl ether) were added and homogenized at an internal temperature of 100°C. Then, a mixed solution of 0.2 g of p-toluenesulfonic acid monohydrate and 3.0 g of PGME, which had been previously mixed and homogenized, was slowly added dropwise, and the reaction was carried out at an internal temperature of 120°C for 8 hours. After the reaction was completed, the temperature was returned to room temperature, 150 g of ultrapure water was added while stirring, and after standing for 1 hour, the upper layer was fractionated. Further, it was dissolved in 30 g of PGME, and the same operation was repeated twice. Then, 300 ml of MIBK (methyl isobutyl ketone) was added, and washing was performed 4 times with 200 ml of pure water, and the organic layer was dried under reduced pressure. Then, 20 g of a tin raw material (Sn-1) and 300 g of toluene were added and stirred at 130°C for 8 hours. After the reaction, the solvent was removed under reduced pressure to obtain (R-4). [Chemical formula]

[0198] [Synthesis of Compound (R-5) for Metal-Containing Film in Comparative Example] A titanium compound reported in [Synthesis Example A-II] of Japanese Patent No. 6189758 was synthesized as a compound having a metal different from the metal-containing film-forming compound of the present invention. While stirring a solution of 284 g of titanium tetraisopropoxide (manufactured by Tokyo Chemical Industry Co., Ltd.) in 500 g of IPA (isopropyl alcohol), a solution of 27 g of deionized water in 500 g of IPA was added dropwise at room temperature over 2 hours. To the resulting solution, 120 g of 2-methyl-2,4-pentanediol was added, and the mixture was stirred at room temperature for 30 minutes. This solution was concentrated under reduced pressure at 30 °C, then further heated to 60 °C, and heating was continued under reduced pressure until no distillate was obtained. When no distillate was observed, 1,200 g of PGMEA was added, and the mixture was heated at 40 °C under reduced pressure until no IPA distilled off, to obtain 1,000 g of a PGMEA solution of a titanium-containing compound (R-5) (compound concentration: 20% by mass).

[0199] [Synthesis of Resin (R-6) for Organic Film in Comparative Example] Under a nitrogen atmosphere, 160.2 g of 1,5-dihydroxynaphthalene, 56.8 g of formaldehyde, and 300 g of PGME (propylene glycol monomethyl ether) were added and homogenized at an internal temperature of 100 °C. Then, a mixture of 8.0 g of p-toluenesulfonic acid monohydrate and 8.0 g of PGME, which had been previously mixed and homogenized, was slowly added dropwise, and the reaction was carried out at an internal temperature of 80 °C for 8 hours. After completion of the reaction, the mixture was cooled to room temperature, 2,000 ml of MIBK was added, and the mixture was washed 6 times with 500 ml of pure water, and the organic layer was dried under reduced pressure. After adding 300 g of THF to the residue to form a homogeneous solution, the solution was crystallized in 2,000 g of hexane. The precipitated crystals were separated by filtration, washed twice with 500 g of hexane, and recovered. The recovered crystals were vacuum-dried at 70 °C to obtain resin (R-6). When the weight average molecular weight (Mw) and dispersity (Mw / Mn) were determined by GPC, the following results were obtained. (R-6): Mw = 3,300, Mw / Mn = 2.54 [Chemical Formula]

[0200] "Evaluation of Solvent Solubility and Heat Resistance" The solvent solubility and heat resistance of metal-containing compounds were evaluated. The compounds (M-1) to (M-16) synthesized in Synthesis Examples 1 to 16 and the comparative example compounds (R-1) to (R-5) were each prepared to be a 15.0 wt% solution of propylene glycol monomethyl ether acetate (PGMEA) and cyclohexanone (CyHO). After stirring for 24 h, those that were completely dissolved were marked as 〇, those with partial undissolved were marked as △, and those that were completely suspended were marked as ×. Also, 3.0 mg of each was weighed, and using RIGAKU's Thermo plus EVO2, the temperature was raised from 30 °C to 300 °C at 10 °C / min in the atmosphere. At this time, those with a weight loss of 40% or less when the temperature was raised to 300 °C were marked as A, those with 40 - 60% were marked as B, and those with a weight loss of more than 60% were marked as C. These results are shown in Table 4.

[0201]

Table 4

[0202] As shown in Table 4, it was confirmed that the compounds (M-1) to (M-16) for forming a metal-containing film of the present invention can be prepared as a solution with cyclohexanone and have sufficient solubility. Also, it was confirmed that the metal-containing film-forming compounds (M-9) to (M-16) with disrupted symmetry of the compound can also be prepared as a solution with PGMEA and exhibit excellent solvent solubility. Also, although the comparative example compounds, which are a group of compounds with some elements of the present invention removed, showed similar solubility results, (R-4) with a structure in which tin was introduced into all of the repeating units of the polymer had no solubility. Also, in TG-DTA measurements, all of the compounds of the present invention had a weight loss of 40% or less when the temperature was raised to 500 °C, but in the comparative example compounds, (R-2) had a 49% decrease, (R-3) had a 68% decrease, and (R-5) had a 56% decrease. Compared with these, it was confirmed that the compounds of the present invention are excellent in heat resistance.

[0203] [Composition UDL-1 for Forming Metal-Containing Film] Compound (M-1) for forming a metal-containing film was dissolved in a solvent of cyclohexanone (CyHO) containing 0.5% by mass of surfactant FC-4430 (manufactured by Sumitomo 3M Limited) at the ratio shown in Table 5, and filtered through a 0.2 μm membrane filter to prepare a composition for forming a metal-containing film (UDL-1).

[0204] [Preparation of Compositions for Forming Metal-Containing Films (UDL-2 to 23), Compositions for Forming Metal-Containing Films for Comparative Examples (Comparative Example UDL-1 to 5)] Except that the types and contents of the respective components were as shown in Table 5, the same operations as those for UDL-1 were performed to prepare each chemical solution. In Table 5, "-" indicates that the corresponding component was not used. The crosslinking agent used was the following formula (C-1), the high-boiling solvent (B2-1) used was 1,6-diacetoxyhexane: boiling point 260°C, the polymer (E-1) for promoting fluidity was used, and the thermal acid generator (TAG) used was the following formula (F-1).

[0205] [Crosslinking Agent] The crosslinking agent (C-1) used in the composition for forming a metal-containing film is shown below. [Chemical Formula]

[0206] [Synthesis Example of Polymer for Promoting Fluidity] Synthesis of Polymer (E-1) for Promoting Fluidity Under a nitrogen atmosphere, 20.0 g of cresol novolak, 27.6 g of potassium carbonate, and 100 g of DMF were added to make a homogeneous dispersion at an internal temperature of 50°C. 11.9 g of propargyl bromide was slowly added, and the reaction was carried out at an internal temperature of 50°C for 24 hours. 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. Further, the organic layer was washed 6 times with 100 g of 3% aqueous nitric acid solution and 100 g of pure water, and then the organic layer was dried under reduced pressure to obtain resin (E-1). When the weight average molecular weight (Mw) and dispersity (Mw / Mn) were determined by GPC, the following results were obtained. (E-1): Mw = 8,500, Mw / Mn = 3.46

Chem.

[0207] [Thermal acid generator] The thermal acid generator (F-1) used in the composition for forming a metal-containing film is shown below.

Chem.

[0208]

Table 5

[0209] [Film formation property test] The composition for forming a metal-containing film (UDL-1 to 23, Comparative Example UDL-1 to 4) prepared above was applied onto a silicon substrate, baked at 180 °C for 60 seconds, and then the film thickness (a [nm]) after additional baking at 250 °C for 60 seconds was measured. Further, the film thickness from the center part to the outer peripheral part of the substrate was measured, and the film thickness difference between the maximum film thickness and the minimum film thickness among them, Range (b [nm]) was calculated, and the in-plane uniformity ((b / a)×100) was determined. Furthermore, PGMEA solvent was dispensed thereon, left standing for 30 seconds, spin-dried, baked at 100 °C for 60 seconds to evaporate PGMEA (Rework), and the film thickness (c [nm]) was measured. The film thickness difference before and after PGMEA treatment (remaining film ratio: (c / a)×100) was determined. The results are shown in Table 6 below.

[0210]

Table 6

[0211] As shown in Table 6, the composition for forming a metal-containing film of the present invention (Examples 1-1 to 1-23) has an in-plane uniformity of 5.0% or less after a high-temperature additional baking treatment at 250°C, and a film with less unevenness and flatness can be formed, and it was confirmed that the film has excellent film-forming properties. On the other hand, Comparative Examples 1-1 to 1-2 using Comparative Example Compound (R-1) in which there is no T unit in the present invention and there is only one tin atom in one molecule or Comparative Example Compound (R-2) composed only of T units had relatively good in-plane uniformity, but the results were inferior to those of the Examples using the compound group of the present invention. This is presumably because the radical cross-linking does not occur efficiently due to the small number of radical active units of the Sn-alkyl bond, and the film is uneven due to sublimates and decomposition products. Further, in Comparative Example 1-3 using Comparative Example Compound (R-3) in which there are a plurality of tin atoms in one molecule but no diol unit and is composed only of esters, the film had large unevenness due to insufficient molecular weight and the influence of sublimates. In Comparative Example 1-4 using Comparative Example UDL-4 containing the titanium compound (R-5) reported in [Synthesis Example A-II] of Japanese Patent No. 6189758, a film with many unevennesses with an in-plane uniformity exceeding 5.0% was formed after the baking treatment, and the film-forming properties were poor. This is presumably because the titanium compound has poor heat resistance, a large amount of sublimates, and a large volume shrinkage, etc. In addition, Examples 1-17 to 1-20 using UDL-17 to 20 to which a cross-linking agent (C-1) was added had improved in-plane uniformity compared to Examples 1-5, 6, 8, and 10 using UDL-5, 6, 8, and 10 to which no cross-linking agent was added. This is presumably because the cross-linking reaction proceeded more efficiently due to the cross-linking agent, and the generation of sublimates and decomposition products could be suppressed. Also, Example 1-22 using UDL-22 to which an acid generator (F-1) was added had a higher residual film rate after rework compared to Example 1-14 to which no acid generator was added, suggesting that the cross-linking reaction proceeded further. In addition, it was also confirmed that there was no significant difference in the in-plane uniformity and the residual film rate after rework when comparing Examples with and without the addition of a fluidity promoter or a high-boiling solvent.

[0212] [Evaluation of Embedding Characteristics] The above-described metal-containing film-forming compositions (UDL-1 to 23) and Comparative Examples UDL-3 and 4 were each applied onto 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), heated at 250 °C for 60 seconds using a hot plate to form a metal-containing film with a film thickness of 100 nm. The substrate used was a base substrate 9 (SiO2 wafer substrate) having a dense line & space pattern as shown in FIGS. 3(Q) (plan view) and (R) (cross-sectional view). The cross-sectional shape of each obtained wafer substrate was observed using an electron microscope (S-4700) manufactured by Hitachi, Ltd. to confirm the possibility of embedding into the stepped substrate. The results are shown in Table 7. When using a metal-containing film-forming composition with poor embedding characteristics, in this evaluation, the stepped substrate cannot be successfully embedded. When using a metal-containing film-forming composition with good embedding characteristics, in this evaluation, as shown in FIG. 3(S), the space between the lines of the base substrate 9 having a dense line & space pattern can be filled without gaps. 〇 indicates embeddable without large voids, △ indicates embeddable but large voids are generated, and × indicates non-embeddable.

[0213]

Table 7

[0214] As shown in Table 7, in Examples 2-1 to 2-23 using the resist metal-containing film-forming composition of the present invention, when baked at 250 °C, it was possible to fill the dense line & space pattern without generating voids, and it was confirmed that they had good embedding characteristics. On the other hand, in Comparative Example 2-1 using Comparative Example UDL-3 with poor film-forming properties, embedding was not possible, and in Comparative Example 2-2 using Comparative Example UDL-4 containing the titanium compound (R-5) reported in [Synthesis Example A-II] of Japanese Patent No. 6189758, voids were observed at the bottom of the pattern. This is because, as observed in the above heat resistance evaluation and film-forming property evaluation of the compounds of the present invention, there are few sublimates due to high-temperature baking and the volume shrinkage is small, so it is possible to fill the step without generating voids. On the other hand, it is presumed that Comparative UDL-3 and 4 with poor heat resistance have a large amount of sublimates and large volume shrinkage, resulting in the generation of voids or the inability to embed.

[0215] [Tin content · Etching resistance test] The metal-containing film-forming compositions (UDL-1, 2, 5, 7, 13, 15 to 17, 19) prepared above and Comparative Examples UDL-1 to 2 with relatively good in-plane uniformity and Comparative Example UDL-5 which is an organic film-forming composition were applied onto a silicon substrate, heated at 250 °C for 60 seconds using a hot plate, and Comparative Example UDL-5 was heated for 120 seconds to form a metal-containing film and an organic film. The elemental ratio of the surface was calculated using XPS K-ALPHA Surface Analysis (manufactured by Thermo SCIENTIFIC) and converted to mass%. Further, an etching test was performed with a CF-based gas and an O2-based gas under the following conditions, and the film thickness difference of the organic film before and after etching was determined. The results are shown in Table 8. For etching, a dry etching apparatus TE-8500 manufactured by Tokyo Electron Limited was used.

[0216] The CF4-based gas etching conditions are as shown below. Chamber pressure 200 mT RF power 300 W CF4 gas flow rate 100 sccm Time 20 sec

[0217] The O2-based gas etching conditions are as shown below. Chamber pressure 500 mT RF power 100 W O2 gas flow rate 30 sccm N2 gas flow rate 270 sscm Time 20 sec

[0218]

Table 8

[0219] As shown in Table 8, in Examples 3-1 to 3-9 using the resist metal-containing film-forming composition of the present invention, it was confirmed that the tin content rate of the film after firing exceeded 70 wt% regardless of the presence or absence of additives. On the other hand, in Comparative Examples 3-1 and 3-2 using Comparative UDL-1 and 2 in which only one tin atom exists in one molecule, the tin content rate was less than 55 wt%, and it was confirmed that they were inferior in tin content rate. Furthermore, in Examples 3-1 to 3-5 using UDL-1, 2, 5, 7, and 13 without additives, the tin content rate was 80 wt% or more, and it was found that the film after firing had a high tin content rate. It was confirmed that a film having a high tin content rate was obtained by containing a plurality of tin atoms in one molecule, and it was shown that secondary electron emission due to EUV light absorption could be expected. Furthermore, in the etching resistance evaluation, the higher the tin content rate, the better the etching resistance for both CF-based gas and O2-based gas. Particularly regarding O2 etching, the etching resistance was greatly improved compared to Comparative Example 3-3 of an organic underlayer film not containing tin.

[0220] From the above, the compound for forming a metal oxide film of the present invention is an organotin compound that highly combines heat resistance and a high tin content rate. Therefore, the 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 resist underlayer film material having both film-forming properties and embedding properties, and is extremely useful as a resist underlayer film material used in a multilayer resist method and a reverser used in a tone inversion etching method.

[0221] This 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). [Chemical formula] (In the general formula (M), T is independently the following general formula (T-1) or (T-2), P is independently *OCOR (* represents the bonding part with the Sn atom, and R represents a monovalent organic group), Q is independently 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 hydrocarbon 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, a substituted or unsubstituted arylalkyl group having 7 to 31 carbon atoms, a halogen atom, or an alkoxy group having 1 to 20 carbon atoms. Also, n1, n2, and n3 are integers such that n1≥1, n2≥0, n3≥1, and n1 + n2 + n3 = 4. When n1≥2, the Ts may be the same or different from each other. When n2 = 2, the Ps may be the same or different from each other. When n3≥2, the Qs may be the same or different from each other.) [Chemical formula] (In the general formulas (T-1) and (T-2), 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 hydrocarbon 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 * is the bonding portion with the Sn atom in the general formula (M). W1 is a substituted or unsubstituted linear, branched or cyclic saturated or unsaturated hydrocarbon group having 1 to 40 carbon atoms (including an aromatic ring group), and the hydrocarbon group contains an oxygen atom, a nitrogen atom or a sulfur atom as a hetero atom, and may form an ether bond, a carbonyl group, an ester group or an amide group, or may form a heterocyclic structure through the hetero atom. R2 represents 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 hydrocarbon group having 2 to 20 carbon atoms containing one or more double bonds or triple bonds, a hydroxyl group, an amino group or a halogen atom, s1 is an integer of 0 to 1, and m is an integer of 0 to 1. W2 is a substituted or unsubstituted linear, branched or cyclic saturated or unsaturated hydrocarbon group having 1 to 40 carbon atoms (including an aromatic ring group), and the hydrocarbon group contains an oxygen atom, a nitrogen atom or a sulfur atom as a hetero atom, and may form an ether bond, a carbonyl group, an ester group or an amide group, or may form a heterocyclic structure through the hetero atom. s2 is an integer of 0 to 1. s3 is 1 or 2. When s3 is 1, R3 is a hydrogen atom or a hydrocarbon group having a hydroxyl group with 1 to 10 carbon atoms. When s3 is 2, R3 is an oxygen atom and together with the carbon atom to which it is bonded forms a carbonyl group, and W2 and R3 may be bonded to each other to form a ring structure.) [2]: In the general formula (T-1), W1 is a linear, branched, or cyclic saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms (including an aromatic ring group) which may contain a hydroxyl group or an amino group (including an aromatic ring group), and the hydrocarbon group may contain an oxygen atom, a nitrogen atom, or a sulfur atom and may form an ether bond, a carbonyl group, or an ester group, or is any of the groups represented by the following general formulas (W1-1) to (W1-4). A compound for forming a metal-containing film according to [1]. [Chemical formula] (In the general formulas (W1-1) to (W1-4), R W is a divalent organic group having 1 to 23 carbon atoms, #1 represents a bonding part with an ester group, and #2 represents a bonding part with a benzene ring.) [3]: In the general formula (T-2), W2 is a linear, branched, or cyclic saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms (including an aromatic ring group) which may contain a hydroxyl group or an amino group, or a cyclic hydrocarbon group bonded to R3 (the hydrocarbon group may contain an oxygen atom, a nitrogen atom, or a sulfur atom and may form an ether bond, a carbonyl group, or an ester group), or is any of the groups represented by the following general formulas (W2-1) to (W2-4). A compound for forming a metal-containing film according to [1] or [2]. [Chemical formula] (In the general formulas (W2-1) to (W2-4), R W is a divalent organic group having 1 to 23 carbon atoms, and #1 and #2 each represent a bonding part with an ester group and a carbon atom, respectively.) [4]: R W in the general formulas (W1-1) to (W1-4) is an unsaturated hydrocarbon group having 2 to 23 carbon atoms. A compound for forming a metal-containing film according to [2]. [5]: R W is a group represented by the following general formula (1). A compound for forming a metal-containing film according to [4]. [Chemical formula] (In the general formula (1), 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 bonding portion with a carbonyl group, and *1 and *2 may be reversed.) [6]: The R W in the general formulas (W2-1) to (W2-4) is an unsaturated hydrocarbon group having 2 to 23 carbon atoms, which is a compound for forming a metal-containing film according to [3]. [7]: The R W is a group represented by the following general formula (1), which is a compound for forming a metal-containing film according to [6]. [Chemical formula] (In the general formula (1), R a , R b and R c are 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 bonding portion with a carbonyl group, and *1 and *2 may be reversed.) [8]: In the general formula (M), n2 is 1, and the R of *OCOR of P is any one of the groups represented by the following general formulas (A-1) to (A-4), the following general formula (3), and the following general formula (4), which is a compound for forming a metal-containing film according to any one of [1] to [7]. [Chemical formula] (In the general formulas (A-1) to (A-4), Y A1 , Y A2 may be the same as or different from each other, and is a substituted or unsubstituted divalent organic group having 1 to 23 carbon atoms and being saturated or having 2 to 23 carbon atoms and being unsaturated, a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, or a substituted or unsubstituted arylalkylene group having 7 to 31 carbon atoms. R Ais a hydrogen atom, a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms that is saturated or 2 to 20 carbon atoms that is unsaturated, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted arylalkyl group having 7 to 31 carbon atoms, and R A1 is an organic group in which a protecting group is eliminated by the action of either or both of an acid and heat to generate one or more hydroxyl groups or carboxyl groups, and * represents a bonding portion with a carbonyl group.)

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[10] : The metal-containing film-forming compound according to [9], wherein Y in the general formulas (A-1) to (A-4), X in the general formula (3), or X in the general formula (4) is a group represented by the following general formula (1). A1

Chemical formula

[11] : A metal-containing film-forming composition that functions as a resist underlayer film material used in semiconductor manufacturing, characterized by containing (a) a metal-containing film-forming compound and (b) an organic solvent according to any one of [1] to

[10] . ​​

[12] : The composition is a composition for forming a metal-containing film that can be used as an underlayer film for a resist in a multilayer resist method, and further contains at least one of (c) a crosslinking agent, (d) a surfactant, (e) a fluidity promoter, and (f) an acid generator. The composition for forming a metal-containing film according to

[11] .

[13] : The metal-containing film-forming composition according to

[11] or

[12] , characterized in that the organic solvent (b) is a mixture of at least one organic solvent having a boiling point of less than 180°C and at least one organic solvent having a boiling point of 180°C or higher.

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

[11] to

[13] on a substrate to be processed and then performing heat treatment. (I-2) A step of forming a resist upper layer film on the metal-containing film using a photoresist material. (I-3) After pattern exposure of the resist upper layer film, developing with a developer to form a pattern on the resist upper layer film. (I-4) A step of transferring the pattern to the metal-containing film by dry etching using the resist upper layer film 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 is formed as a mask to form a pattern on the substrate to be processed. A pattern forming method characterized by comprising the above steps.

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

[11] to

[13] on a substrate to be processed and then performing heat treatment. (II-2) A step of forming a resist intermediate film on the metal-containing film. (II-3) A step of forming a resist upper layer film on the resist intermediate film using a photoresist material. (II-4) After pattern exposure of the resist upper layer film, developing with a developer to form a pattern on the resist upper layer film. (II-5) A step of transferring a pattern to the resist intermediate film by dry etching using the resist upper layer film on which the pattern is 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 on which the pattern is 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 is formed as a mask to form a pattern on the substrate to be processed A pattern forming method characterized by comprising the above steps.

[16] : A method of forming a pattern on a substrate to be processed, (III-1) A step of forming a metal-containing film by applying any one of the metal-containing film forming compositions from

[11] to

[13] on the substrate to be processed and then performing heat treatment, (III-2) A step of forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film on the resist lower layer film, (III-3) A step of forming an organic thin film on the inorganic hard mask intermediate film, (III-4) A step of forming a resist upper layer film using a photoresist material on the organic thin film, (III-5) A step of forming a pattern on the resist upper layer film by pattern exposure and then developing 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 is 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 on which the pattern is 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 is formed as a mask to form a pattern on the substrate to be processed A pattern forming method characterized by comprising the above steps.

[17] : A method of forming a pattern on a substrate to be processed, (IV-1) A step of forming a resist lower layer film on the substrate to be processed, (IV-2) A step of forming a metal-containing film by applying any one of the metal-containing film-forming compositions from

[11] to

[13] on the resist lower layer and then performing heat treatment. (IV-3) A step of forming a resist upper layer film using a photoresist material on the metal-containing film, or a step of forming an organic adhesion film by spin coating on the metal-containing film and then forming a resist upper layer film using a photoresist material thereon. (IV-4) A step of pattern-exposing the resist upper layer film and then developing it with a developer to form a pattern in the resist upper layer film. (IV-5) A step of transferring the 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 with the pattern as a mask. (IV-6) A step of transferring the pattern to the resist lower layer film by dry etching using the metal-containing film with the pattern transferred as a mask, and (IV-7) A step of processing the substrate to be processed using the resist lower layer film with the pattern formed as a mask to form a pattern on the substrate to be processed. A pattern formation method characterized by comprising the above steps.

[18] : A method of forming a pattern on a substrate to be processed, comprising: (V-1) A step of forming a resist lower layer film on the substrate to be processed. (V-2) A step of forming a combination of a resist intermediate film or 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 lower layer film. (V-3) A step of 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. (V-4) A step of pattern-exposing the resist upper layer film and then developing it with a developer to form a pattern in the resist upper layer film. (V-5) A step of 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 with the pattern formed as a mask. (V-6) Using the resist intermediate film or the inorganic hard mask intermediate film onto which the pattern has been transferred as a mask, transferring the pattern to the resist underlayer film by dry etching; (V-7) Applying any one of the composition for forming a metal-containing film from

[11] to

[13] onto the resist underlayer film on which the pattern has been formed, and then performing heat treatment to coat the metal-containing film and fill the spaces between the resist underlayer film patterns with the metal-containing film; (V-8) 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) 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) Removing the resist underlayer film on which the pattern has been formed and whose surface is exposed by dry etching to form an inverted pattern of the original pattern in the metal-containing film; (V-11) Using the metal-containing film on which the inverted pattern has been formed as a mask to process the substrate to be processed and form an inverted pattern on the substrate to be processed; A pattern forming method, characterized by comprising the above steps.

[19] : The pattern forming method according to

[16] or

[18] , characterized in that the inorganic hard mask intermediate film is formed by a CVD method or an ALD method.

[0222] Note that the present invention is not limited to the above embodiments. The above embodiments are examples, and any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and exhibits the same operational effects is included in the technical scope of the present invention.

Explanation of Reference Numerals

[0223] 1... Substrate to be processed, 2... Processed layer, 2a... Pattern (pattern formed on the processed layer); 3... Metal-containing resist underlayer film, 3a... Metal-containing resist underlayer film pattern; 4…Silicon-containing resist intermediate film, 4a…Pattern of silicon-containing resist intermediate film, 5…Resist upper layer film, 5a…Pattern of resist upper layer film, 6…Exposed portion, 7…Resist lower layer film made of a coating type organic lower layer film material, 7a…Pattern of resist lower layer film made of a coating type organic lower layer film material, 8…Metal-containing film, 8a…Pattern of metal-containing film obtained by inverting the pattern of the resist lower layer film, 9…Substrate having dense lines & spaces, 10…Metal-containing resist lower layer film.

Claims

1. A compound for forming a metal-containing film, characterized in that the compound is represented by the following general formula (M). 【Chemical 1】 (In the general formula (M), T is independently the following general formula (T-1) or (T-2), P is independently *O COR (* represents the bonding part with the Sn atom, and R represents a monovalent organic group), and Q is independently 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 hydrocarbon 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, a substituted or unsubstituted arylalkyl group having 7 to 31 carbon atoms, a halogen atom, or an alkoxy group having 1 to 20 carbon atoms. Also, n １ n ２ n ３ is n １ ≧1, n ２ ≧0, n ３ ≧1, and n １ + n ２ + n ３ = 4 is an integer that satisfies, and when n １ ≧2, T may be the same or different, and when n ２ = 2, P may be the same or different, and when n ３ ≧2, Q may be the same or different.) 【Chemical Formula 2】 (In the general formulas (T-1) and (T-2), 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 hydrocarbon 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 * is the bonding part with the Sn atom in the general formula (M). W １ is a substituted or unsubstituted linear, branched or cyclic saturated or unsaturated hydrocarbon group having 1 to 40 carbon atoms (including an aromatic ring group), and the hydrocarbon group contains an oxygen atom, a nitrogen atom or a sulfur atom as a hetero atom, and may form an ether bond, a carbonyl group, an ester group or an amide group, and may form a heterocyclic structure via the hetero atom. R ２ 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 hydrocarbon group having 2 to 20 carbon atoms containing one or more double bonds or triple bonds, a hydroxyl group, an amino group or a halogen atom, s １ is an integer of 0 to 1, and m is an integer of 0 to 1. W ２ is a substituted or unsubstituted linear, branched or cyclic saturated or unsaturated hydrocarbon group having 1 to 40 carbon atoms (including an aromatic ring group), and the hydrocarbon group contains an oxygen atom, a nitrogen atom or a sulfur atom as a hetero atom, and may form an ether bond, a carbonyl group, an ester group or an amide group, and may form a heterocyclic structure via the hetero atom. s ２ is an integer of 0 to 1. s ３ is 1 or 2, and when s ３ is 1, R ３ is a hydrogen atom or a hydrocarbon group having a hydroxyl group with 1 to 10 carbon atoms, and when s ３ is 2, R ３ is an oxygen atom and together with the carbon atom to which it is bonded forms a carbonyl group, and W ２ and R ３ may be bonded to each other to form a ring structure.)

2. In the general formula (T-1), W １ is a linear, branched or cyclic saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms which may contain a hydroxyl group or an amino group (including an aromatic ring group) (the hydrocarbon group contains an oxygen atom, a nitrogen atom, a sulfur atom, and may form an ether bond, a carbonyl group, an ester group) or any of the groups represented by the following general formula (W １ -1) to (W １ -4). The compound for forming a metal-containing film according to claim 1, characterized in that it is any of them. [Chemical Formula 3] (In the general formulas (W １ -1) to (W １ -4), R Ｗ is a divalent organic group having 1 to 23 carbon atoms, # １ is a bonding portion with an ester group, # ２ represents a bonding portion with a benzene ring.)

3. In the general formula (T-2), W ２ is a linear, branched or cyclic saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms which may contain a hydroxyl group or an amino group (including an aromatic ring group), or a cyclic hydrocarbon group bonded to R ３ (the hydrocarbon group may contain an oxygen atom, a nitrogen atom, a sulfur atom and may form an ether bond, a carbonyl group, an ester group), or any of the groups represented by the following general formulas (W ２ -1) to (W ２ -4), the compound for forming a metal-containing film according to claim 1. 【Chemical Formula 4】 (In the general formulas (W ２ -1) to (W ２ -4), R Ｗ is a divalent organic group having 1 to 23 carbon atoms, and # １ , # ２ each represents an ester group and a bonding portion with a carbon atom.)

4. The above general formula (W １ -1) to (W １ -4), wherein R Ｗ is an unsaturated hydrocarbon group having 2 to 23 carbon atoms, and the compound for forming a metal-containing film according to claim 2.

5. The aforementioned R Ｗ The compound for forming a metal-containing film according to claim 4, wherein R is a group represented by the following general formula (1). 【Chemical Formula 5】 (In the general formula (1), R ａ , R ｂ and R ｃ are 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 bonding portion with a carbonyl group, and *1 and *2 may be reversed.)

6. The above general formula (W ２ -1) to (W ２ -4), wherein R Ｗ is an unsaturated hydrocarbon group having 2 to 23 carbon atoms, and the compound for forming a metal-containing film according to claim 3.

7. The above-mentioned R Ｗ The compound for forming a metal-containing film according to claim 6, wherein is a group represented by the following general formula (1). [Chemical Formula 6] (In the general formula (1), R ａ , R ｂ and R ｃ are 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 bonding portion with a carbonyl group, and *1 and *2 may be reversed.)

8. In the general formula (M), n ２ is 1, and R of *OCOR of P is any of the groups represented by the following general formulas (A-1) to (A-4), the following general formula (3), and the following general formula (4). The compound for forming a metal-containing film according to claim 1, characterized in that 【Chemical Formula 7】 (In the general formulas (A-1) to (A-4), Y Ａ１ , Y Ａ２ may be the same as or different from each other, and is a substituted or unsubstituted divalent organic group having 1 to 23 carbon atoms and being saturated or having 2 to 23 carbon atoms and being unsaturated, a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, or a substituted or unsubstituted arylalkylene group having 7 to 31 carbon atoms. R Ａ is a hydrogen atom, a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms and being saturated or having 2 to 20 carbon atoms and being unsaturated, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted arylalkyl group having 7 to 31 carbon atoms, and R Ａ１ is an organic group in which a protecting group is eliminated by the action of either or both of an acid and heat represented by the following general formula (2) to generate one or more hydroxyl groups or carboxyl groups, and * represents a bonding portion with a carbonyl group.) 【Chemical 8】 (In the general formula (2), R Ａ２ is an organic group in which a protecting group is removed by the action of either an acid, heat, or both, and * represents the bonding portion with Y Ａ１ or Y Ａ２ .) 【Chemical Formula 9】 (In the general formula (3), X is a divalent organic group having 1 to 31 carbon atoms, B is the following general formula (B), and * represents the bonding part with the carbonyl group.) 【Chemical 10】 (In the general formula (B), Y Ｂ is a substituted or unsubstituted divalent organic group having 1 to 20 carbon atoms and being saturated or having 2 to 20 carbon atoms and being unsaturated, a substituted or unsubstituted divalent arylene group having 6 to 30 carbon atoms, or a substituted or unsubstituted divalent arylalkylene group having 7 to 31 carbon atoms, and R Ｂ is a hydroxyl group or any of the structures represented by the following general formulas (B-1) to (B-3).) 【Chemical 11】 (In the 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, and * represents the bonding part with Y Ｂ .) 【Chemical Formula 12】 (In the general formula (4), X is a divalent organic group having 1 to 31 carbon atoms, C is any of the groups represented by the following general formulas (C-1) to (C-4), and * represents the bonding part with the carbonyl group.) 【Chemical 13】 (In the general formulas (C-1) and (C-3), R Ｃ１ is a hydrogen atom or a methyl group, and in the same formula, they may be the same as or different from each other. In (C-3) and (C-4), R Ｃ２ is a hydrogen atom 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 bonding part with the carbonyl group.)

9. Y in the general formulas (A-1) to (A-4) Ａ１ , X in the general formula (3), or X in the general formula (4) is an unsaturated hydrocarbon group having 2 to 23 carbon atoms, and the compound for forming a metal-containing film according to claim 8.

10. Y in the general formulas (A-1) to (A-4) above Ａ１ , the metal-containing film-forming compound according to claim 9, wherein X in the general formula (3) or X in the general formula (4) is a group represented by the following general formula (1). 【Chemical 14】 (In the general formula (1), R ａ , R ｂ and R ｃ are 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 bonding portion with a carbonyl group, and *1 and *2 may be reversed.)

11. A composition for forming a metal-containing film that functions as a resist underlayer film material used in semiconductor manufacturing, comprising (a) a compound for forming a metal-containing film and (b) an organic solvent according to any one of Claims 1 to 10. A composition for forming a metal-containing film, characterized in that it contains the above.

12. The composition is a composition for forming a metal-containing film that can be used as a resist underlayer film in a multilayer resist method, and further contains one or more of (c) a crosslinking agent, (d) a surfactant, (e) a fluidity promoter, and (f) an acid generator. The composition for forming a metal-containing film according to Claim 11, characterized in that it contains the above.

13. The composition for forming a metal-containing film according to Claim 11, 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.

14. A method for forming a pattern on a substrate to be processed, comprising: (I-1) A step of forming a metal-containing film by applying the composition for forming a metal-containing film according to Claim 11 on a substrate to be processed and then performing a heat treatment; (I-2) A step of forming a resist upper layer film on the metal-containing film using a photoresist material; (I-3) A step of forming a pattern on the resist upper layer film by pattern exposure and then developing with a developer; (I-4) A step of transferring the pattern to the metal-containing film by dry etching using the resist upper 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 is formed as a mask to form a pattern on the substrate to be processed A pattern forming method, characterized by having the above steps.

15. A method for forming a pattern on a substrate to be processed, comprising: Step (II-1): A step of forming a metal-containing film by applying the composition for forming a metal-containing film according to claim 11 on a substrate to be processed and then performing a heat treatment. Step (II-2): A step of forming a resist intermediate film on the metal-containing film. Step (II-3): A step of forming a resist upper layer film on the resist intermediate film using a photoresist material. Step (II-4): A step of performing pattern exposure on the resist upper layer film and then developing it with a developer to form a pattern in the resist upper layer film. Step (II-5): A step of transferring the pattern to the resist intermediate film by dry etching using the resist upper layer film with the pattern formed thereon as a mask. Step (II-6): A step of transferring the pattern to the metal-containing film by dry etching using the resist intermediate film with the pattern transferred thereon as a mask, and Step (II-7): A step of processing the substrate to be processed using the metal-containing film with the pattern formed thereon as a mask to form a pattern on the substrate to be processed A pattern forming method characterized by comprising the above steps.

16. A method for forming a pattern on a substrate to be processed, comprising: Step (III-1): A step of forming a metal-containing film by applying the composition for forming a metal-containing film according to claim 11 on a substrate to be processed and then performing a heat treatment. Step (III-2): A step of forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film on the resist lower layer film. Step (III-3): A step of forming an organic thin film on the inorganic hard mask intermediate film. Step (III-4): A step of forming a resist upper layer film on the organic thin film using a photoresist material. Step (III-5): A step of performing pattern exposure on the resist upper layer film and then developing it with a developer to form a pattern in the resist upper layer film. Step (III-6): A step of transferring the pattern to the organic thin film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film with the pattern formed thereon as a mask. Step (III-7): A step of transferring the pattern to the metal-containing film by dry etching using the inorganic hard mask intermediate film with the pattern transferred thereon as a mask, and Step (III-8): A step of processing the substrate to be processed using the metal-containing film with the pattern formed thereon as a mask to form a pattern on the substrate to be processed A pattern forming method characterized by comprising the above steps.

17. A method for forming a pattern on a substrate to be processed, comprising: Step (IV-1): A step of forming a resist lower layer 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 11 on the resist lower layer and then performing heat treatment. (IV-3) A step of forming a resist upper layer film using a photoresist material on the metal-containing film, or a step of forming an organic adhesion film by spin coating on the metal-containing film and then forming a resist upper layer film using a photoresist material thereon. (IV-4) A step of pattern-exposing the resist upper layer film and then developing it with a developer to form a pattern in the resist upper layer film. (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 having the pattern formed thereon as a mask. (IV-6) A step of transferring a pattern to the resist lower layer film by dry etching using the metal-containing film having the pattern transferred thereon as a mask, and (IV-7) A step of processing the substrate to be processed using the resist lower layer film having the pattern formed thereon as a mask to form a pattern on the substrate to be processed. A pattern forming method characterized by comprising the above steps.

18. A method for forming a pattern on a substrate to be processed, comprising: (V-1) A step of forming a resist lower layer film on the substrate to be processed. (V-2) A step of forming a combination of a resist intermediate film or 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 lower layer film. (V-3) A step of 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. (V-4) A step of pattern-exposing the resist upper layer film and then developing it with a developer to form a pattern in the resist upper layer film. (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 having the pattern formed thereon as a mask. (V-6) A step of transferring a pattern to the resist lower layer film by dry etching using the resist intermediate film or the inorganic hard mask intermediate film having the pattern transferred thereon as a mask. (V-7) A step of coating a metal-containing film by applying the composition for forming a metal-containing film according to claim 11 on the resist lower layer film having the pattern formed thereon and then performing heat treatment, and filling the spaces between the resist lower layer film patterns with the metal-containing film. (V-8) Chemically strip or dry-etch back the metal-containing film covering the resist underlayer film on which the pattern is formed to expose the upper surface of the resist underlayer film on which the pattern is formed; (V-9) Remove 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) Remove the resist underlayer film on which the pattern is formed with the exposed surface by dry etching to form an inverted pattern of the original pattern in the metal-containing film; (V-11) Process the substrate to be processed using the metal-containing film on which the inverted pattern is formed as a mask to form an inverted pattern on the substrate to be processed. A pattern forming method characterized by comprising the steps.

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

20. The pattern forming method according to claim 18, wherein the inorganic hard mask intermediate film is formed by a CVD method or an ALD method.

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