Metal containing film-forming compounds, metal containing film-forming components, patch formation method

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

[0002] With the increasing integration and speed of LSIs, the miniaturization of pattern rules is progressing rapidly. As a cutting-edge miniaturization technology, ArF immersion lithography is being applied to the mass production of devices at the 45nm node and beyond. In addition, the double exposure (double patterning) process, in conjunction with ArF immersion lithography, has been put into practical use in generations from the 28nm node onward, making it possible to form narrow-pitch patterns that exceed the optical limits.

[0003] Furthermore, in the manufacturing of devices at the 20nm node and beyond, research is underway on multi-patterning processes that create narrower-pitch patterns by repeating exposure and etching three or more times. However, because multi-patterning processes increase the number of steps, they face challenges such as longer manufacturing times, increased defect frequency, decreased productivity, and significantly higher costs.

[0004] In recent years, extreme ultraviolet (EUV) lithography with a wavelength of 13.5 nm has attracted attention as a promising alternative to the combined use of ArF immersion lithography and multiple exposure processes. This technology makes it 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, high sensitivity is strongly required for the resist material to compensate for the insufficient output of the light source. However, the increase in shot noise associated with increased sensitivity leads to an increase in the edge roughness (LER, LWR) of the line pattern, and achieving both high sensitivity and low edge roughness is one of the important challenges in EUV lithography.

[0006] In recent years, the use of metallic materials in resists has been explored as an attempt to increase the sensitivity of resists and reduce the effects of shot noise. Compounds containing metallic elements such as barium, titanium, hafnium, zirconium, and tin have higher absorbance to EUV light compared to organic materials that do not contain metals, and are expected to improve the photosensitivity of resists and suppress the effects of shot noise. Furthermore, metal-containing resist patterns can be expected to enable highly selective etching by combining them with an underlayer made of non-metallic materials.

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

[0008] In particular, molecules containing tin are being actively researched because they excel at absorbing electron beams and extreme ultraviolet light. In the case of organotin polymers, one such example, alkyl ligands are dissociated by light absorption or the secondary electrons generated by it, and negative tone patterning is possible that is not removed by organic developers through crosslinking via oxo bonds with surrounding chains. While such organotin polymers can improve sensitivity while maintaining resolution and line edge roughness, they have not yet reached a level suitable for commercialization (Patent Document 5). Furthermore, many challenges remain, such as insufficient storage stability regarding changes in resist sensitivity.

[0009] To address the above challenges, development using materials containing metallic elements such as titanium, hafnium, zirconium, and tin in the resist underlayer film is also being considered. This eliminates the need for performance improvements such as increased exposure sensitivity and suppression of sensitivity changes under storage conditions, which are challenges with metal-containing resist materials. Furthermore, the inclusion of these metallic elements may provide a resist underlayer film with excellent dry etching resistance. Patent Document 7 reports that materials using Ti compounds exhibit excellent dry etching resistance to CHF3 / CF4 and CO2 / N2 gases.

[0010] On the other hand, challenges when using metal compounds as underlayer films for resists include film formation and embedding properties. For example, while heat resistance is not mentioned in the compound intended for use in photoresists, such as in Patent Document 6, it is not intended for high-temperature baking, which may result in insufficient heat resistance and poor embedding or film formation. Furthermore, while film formation and embedding properties are not mentioned in Patent Document 7, metal oxide compounds generally exhibit significant thermal shrinkage during baking, and high-temperature baking induces a significant deterioration in filling properties. Therefore, there are concerns that they may be insufficient as underlayer materials for resists where heat resistance properties such as film formation and embedding characteristics are required. Patent Document 8 reports that metal compounds modified with specific ligands exhibit excellent embedding properties, but the baking temperature used for the embedding evaluation was a low 150°C, raising concerns that it may be insufficient for underlayer films for resists where heat resistance (for example, properties against heat treatments that may be applied after the formation of the underlayer film) is required. Patent Document 9 provides a resist underlayer film material with excellent embedding properties after baking at 400°C by mixing a metal compound reported in Patent Document 8 with an organic polymer of a specific structure. However, since it is a mixed composition of an inorganic metal compound and an organic polymer, there are concerns about poor film formation due to poor compatibility, deterioration of storage stability, and deterioration of dry etching resistance. [Prior art documents] [Patent Documents]

[0011] [Patent Document 1] Patent No. 5708521 [Patent Document 2] Patent No. 5708522 [Patent Document 3] U.S. Patent No. 9310684 [Patent Document 4] U.S. Patent Application Publication No. 2017 / 0102612 [Patent Document 5] Special Publication No. 2021-162865 [Patent Document 6] Patent No. 7028940 [Patent Document 7] Patent No. 6189758 [Patent Document 8] Patent No. 7050137 [Patent Document 9] Special Publication No. 2022-521531 [Overview of the project] [Problems that the invention aims to solve]

[0012] The present invention has been made in view of the above circumstances, and aims to provide a metal-containing film-forming compound that has excellent dry etching resistance compared to conventional organic underlayer film materials, as well as high film-forming properties and a high tin content; a metal-containing film-forming composition using the compound; and a pattern-forming method using the composition as a resist underlayer film material. [Means for solving the problem]

[0013] To solve the above problems, the present invention provides a metal-containing film-forming compound characterized in that the compound is represented by the following general formula (M). [ka] (In the above general formula (M), T is independently of the following general formula (T-1) or (T-2), P is independently of *OCOR (* represents a bond with a Sn atom, and R represents a monovalent organic group), and Q is independently of a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 aliphatic unsaturated hydrocarbon group containing one or more double or triple bonds, or a substituted or unsubstituted carbon The elements are aryl groups with 6 to 30 carbon atoms, substituted or unsubstituted arylalkyl groups with 7 to 31 carbon atoms, halogen atoms, and alkoxy groups with 1 to 20 carbon atoms. Furthermore, n1, n2, and n3 are integers satisfying n1≧1, n2≧0, and n3≧1, and n1+n2+n3=4. When n1≧2, T may be the same or different; when n2=2, P may be the same or different; and when n3≧2, Q may be the same or different. [ka] (In the above general formulas (T-1) and (T-2), R1 is a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 aliphatic unsaturated hydrocarbon group containing one or more double or triple bonds, a substituted or unsubstituted C6-C30 aryl group, or a substituted or unsubstituted C7-C31 arylalkyl group, and * is the bond with the Sn atom in the above general formula (M). W1 is a substituted or unsubstituted C1-C40 linear, branched or cyclic saturated or unsaturated hydrocarbon group (including aromatic ring 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, or may form a heterocyclic structure via the heteroatom. R2 is a substituted or unsubstituted C1-C20 alkyl group, or a substituted or unsubstituted s1 represents a 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 or triple bonds, a hydroxyl group, an amino group, or a halogen atom, where s1 is an integer from 0 to 1 and m is an integer from 0 to 1. W2 is a substituted or unsubstituted linear, branched, or cyclic saturated or unsaturated hydrocarbon group (including aromatic ring groups) having 1 to 40 carbon atoms, and the hydrocarbon group may contain 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, or a heterocyclic structure via the heteroatom. s2 is an integer from 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 having 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, it forms a carbonyl group, and W2 and R3 may bond to each other to form a ring structure.

[0014] In compounds containing tin, radicals are generated by radical cleavage of the Sn-alkyl bond, leading to crosslinking reactions. Furthermore, since tin is bonded to the catechol or diol unit (T), multiple tin atoms can be introduced into a single molecule, thereby increasing the tin content. Moreover, in the above general formula (M), if n2 is 1 or if n1 is 2 and T is different, the molecular symmetry is broken, which can increase solvent solubility. Therefore, the compounds of the present invention have excellent solvent solubility and are suitable as metal film-forming compositions, and when used as a resist underlayer, they can form films with a high tin content.

[0015] In the above compound, it is preferable that (i) 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 (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 a group represented by the following general formulas (W1-1) to (W1-4). [ka] (In the above general formulas (W1-1) to (W1-4), R W (#1 represents the bond with the ester group, and #2 represents the bond with the benzene ring.)

[0016] Furthermore, in the above compound, (ii) W2 in the general formula (T-2) may be a linear, branched, or cyclic saturated or unsaturated hydrocarbon group (including an aromatic ring group) having 1 to 10 carbon atoms, 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 any of the groups represented by the following general formulas (W2-1) to (W2-4). [ka] (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 an ester group and a bonding portion with a carbon atom.)

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

[0022] Furthermore, in the general formula (M), it is preferable that n2 is 1 and R in *OCOR of P is 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). [ka] (In the above general formulas (A-1) to (A-4), Y A1 , Y A2 Each of these may be the same or different from the others, and is a substituted or unsubstituted saturated or unsaturated divalent organic group having 1 to 23 carbon atoms, 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. A R is a hydrogen atom, a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms in a saturated state or 2 to 20 carbon atoms in an unsaturated state, 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. A1 This is an organic group represented by the following general formula (2) in which a protecting group is removed by the action of either an acid, heat, or both, generating one or more hydroxyl groups or carboxyl groups, and * represents the bond with the carbonyl group. [ka] (In the above general formula (2), R A2 * is an organic group whose protecting group is removed by the action of acid, heat, or both, and * is Y A1 Or Y A2 (This represents the connection point.) [ka] (In the above 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 bond with the carbonyl group.) [ka] (In the above general formula (B), Y B R is a substituted or unsubstituted saturated or unsaturated divalent organic group having 1 to 20 carbon atoms, 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. B (This is either a hydroxyl group or one of the structures shown in the following general formulas (B-1) to (B-3).) [ka] (In the above general formulas (B-1) to (B-3), R B1 is a hydrogen atom or a monovalent organic group with 1 to 10 carbon atoms, q represents 0 or 1, and * represents Y B (This represents the connection point.) [ka] (In the above general formula (4), X is a divalent organic group having 1 to 31 carbon atoms, C is one of the groups represented by the following general formulas (C-1) to (C-4), and * represents the bond with the carbonyl group.) [ka] (In the above general formulas (C-1) and (C-3), R C1 R is a hydrogen atom or a methyl group, and they may be the same or different from each other in the same formula. In (C-3) and (C-4), R C2 This refers to a hydrogen atom or a substituted or unsubstituted saturated or unsaturated monovalent organic group with 1 to 20 carbon atoms (such as an aliphatic hydrocarbon group), a substituted or unsubstituted aryl group with 6 to 30 carbon atoms, or a substituted or unsubstituted arylalkyl group with 7 to 31 carbon atoms. * indicates a bond with a carbonyl group.

[0023] If R has a structure represented by the general formulas (A-1) to (A-4) above, the structure contains an organic group whose protecting group is removed by the action of bulky acid, heat, or both, thereby increasing the solvent solubility of the compound. Furthermore, when this is used in a metal-containing film-forming composition, the protecting group is removed during baking, generating hydroxyl groups and carboxyl groups. The resulting OH and α-hydrogen of the carboxylic acid readily reacts with radicals generated by the cleavage of the tin-carbon bond during baking, causing a crosslinking reaction. Therefore, the compounds of the present invention have excellent thermosetting properties and can suppress volume shrinkage that induces deterioration of film-forming and embedding properties. Furthermore, even during high-temperature baking, it is possible to provide a resist underlayer material with excellent film-forming and embedding properties.

[0024] Furthermore, if R has the structure shown in the general formula (3) above, it contains a hydroxyl group or a crosslinking group with one of the structures shown in the general formulas (B-1) to (B-3) above at its terminal. Therefore, when these are used in a metal-containing film-forming composition, during baking, not only does crosslinking occur between radicals generated by the cleavage of the tin-carbon bond, but also between radicals and crosslinking groups, and between crosslinking groups themselves, resulting in further crosslinking reactions. This provides excellent thermosetting properties, suppresses volume shrinkage that induces deterioration of film-forming and embedding properties, and provides a resist underlayer material with excellent film-forming and embedding properties even after high-temperature baking.

[0025] Furthermore, if R has the structure shown in the general formula (4) above, it includes one of the structures shown in (C-1) to (C-4) at its end, and since this structure has a high crosslinking group density and excellent thermosetting properties, when used in a metal-containing film-forming composition, it is possible to provide a resist underlayer film material with small volume shrinkage during baking and excellent film-forming and embedding properties even after high-temperature baking.

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

[0027] In the above general formulas (A-1) to (A-4), YA1 Furthermore, if X in the above general formula (3) or X in the above general formula (4) is an unsaturated hydrocarbon group having 2 to 23 carbon atoms, the thermosetting properties of the metal-containing film-forming compound can be further improved.

[0028] In this case, Y in the above general formulas (A-1) to (A-4) A1 The X in the above general formula (3), or the X in the above general formula (4), may be a group represented by the following general formula (1). [ka] (In the above general formula (1), R a , R b and R c R is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. a and R b These may be bonded, forming a cyclic substituent. (*1 and *2 represent the bond with the carbonyl group, and *1 and *2 may be reversed.)

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

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

[0031] Such a metal-containing film-forming composition contains organotin compounds with excellent solvent solubility and heat resistance, and therefore can provide a resist underlayer material that has superior dry etching resistance compared to conventional organic underlayer materials, as well as high film-forming properties.

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

[0033] Furthermore, 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-mentioned metal-containing film-forming compound through the addition of a high-boiling-point solvent, the planarization characteristics of the resist underlayer film-forming composition can be further improved.

[0035] Furthermore, the present invention relates to a method for forming a pattern on a substrate to be processed, (I-1) A step of forming a metal-containing film by applying the metal-containing film-forming composition of the present invention onto a substrate to be processed, and then heat-treating it. (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, develop it 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 workpiece substrate using the metal-containing film on which the pattern is formed as a mask to form a pattern on the workpiece substrate. The present invention provides a pattern forming method characterized by having the following features.

[0036] The pattern formation method using the two-layer resist process described above allows for the formation of fine patterns on the workpiece (workpiece substrate).

[0037] Furthermore, the present invention relates to a method for forming a pattern on a substrate to be processed, (II-1) A step of forming a metal-containing film by applying the metal-containing film-forming composition of the present invention onto a substrate to be processed, and then heat-treating it. (II-2) A step of forming a resist interlayer on the metal-containing film, (II-3) A step of forming a resist upper layer film on the resist interlayer film using a photoresist material, (II-4) After pattern exposure of the resist upper layer film, develop it with a developer to form a pattern on the resist upper layer film. (II-5) A step of transferring the pattern to the resist interlayer by dry etching, using the resist upper layer on which the pattern is formed as a mask. (II-6) A step of transferring the pattern to the metal-containing film by dry etching using the resist interlayer on which the pattern has been transferred as a mask, and (II-7) A step of processing the workpiece substrate using the metal-containing film on which the pattern is formed as a mask to form a pattern on the workpiece substrate. The present invention provides a pattern forming method characterized by having the following features.

[0038] The pattern formation method using the above three-layer resist process makes it possible to form fine patterns on a workpiece with high precision.

[0039] Furthermore, the present invention relates to a method for forming a pattern on a substrate to be processed, (III-1) A step of forming a metal-containing film by applying the metal-containing film-forming composition of the present invention onto a substrate to be processed, and then heat-treating it. (III-2) The above Contains metal A step of forming an inorganic hard mask interlayer selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film on a film, (III-3) A step of forming an organic thin film on the inorganic hard mask interlayer, (III-4) A step of forming a resist upper layer film on the organic thin film using a photoresist material, (III-5) After pattern exposure of the resist upper layer film, develop it with a developer to form a pattern on the resist upper layer film. (III-6) A step of transferring the pattern to the organic thin film and the inorganic hard mask interlayer 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 the pattern to the metal-containing film by dry etching using the inorganic hard mask interlayer on which the pattern has been transferred as a mask, and (III-8) A step of processing the workpiece substrate using the metal-containing film on which the pattern is formed as a mask to form a pattern on the workpiece substrate. The present invention provides a pattern forming method characterized by having the following features.

[0040] The pattern formation method using the four-layer resist process described above allows for the formation of fine patterns on a workpiece with high precision.

[0041] In this case, it is preferable to form the inorganic hard mask interlayer by CVD or ALD.

[0042] When the above inorganic hard mask is formed by CVD or ALD, fine patterns can be formed on the workpiece with higher precision.

[0043] Furthermore, the present invention relates to a method for forming a pattern on a substrate to be processed, (IV-1) A step of forming a resist underlayer film on a substrate to be processed. (IV-2) The resist layer below film The process involves applying the metal-containing film-forming composition of the present invention and then heat-treating it to form a metal-containing film. (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 on the metal-containing film by spin coating, and then forming a resist upper layer film thereon using a photoresist material. (IV-4) After pattern exposure of the resist upper layer film, develop it with a developer to form a pattern on the resist upper layer film. (IV-5) Using the resist upper layer film on which the pattern is formed as a mask, a step of transferring the pattern to the metal-containing film, or the organic adhesion film and the metal-containing film, by dry etching. (IV-6) A step of transferring the pattern to the resist underlayer film by dry etching using the metal-containing film on which the pattern has been transferred as a mask, and (IV-7) A step of processing the substrate to be processed using the resist underlayer film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. The present invention provides a pattern forming method characterized by having the following features.

[0044] The pattern formation method using the multilayer resist process described above allows for the formation of fine patterns on a workpiece with high precision.

[0045] Furthermore, the present invention relates to a method for forming a pattern on a substrate to be processed, (V-1) A step of forming a resist underlayer film on the substrate to be processed. (V-2) A step of forming a resist interlayer, or a combination of an inorganic hard mask interlayer selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film, and an organic thin film on the resist underlayer film. (V-3) A step of forming a resist upper layer film using a photoresist material on the resist interlayer film, or a combination of an inorganic hard mask interlayer film and an organic thin film. (V-4) After pattern exposure of the resist upper layer film, develop it with a developer to form a pattern on the resist upper layer film. (V-5) A step of transferring the pattern to the resist interlayer, or the organic thin film and the inorganic hard mask interlayer, by dry etching, using the resist upper layer film on which the pattern is formed as a mask. (V-6) A step of transferring the pattern to the resist underlayer film by dry etching, using the resist interlayer film on which the pattern has been transferred, or an inorganic hard mask interlayer film, as a mask. (V-7) A step of coating the resist underlayer film on which the pattern described above has been formed with the metal-containing film composition of the present invention, and then heat-treating it to coat it with a metal-containing film, thereby filling the spaces between the resist underlayer film patterns with the metal-containing film. (V-8) A step of etching back the metal-containing film covering the resist underlayer film on which the pattern has been formed by chemical stripping or dry etching, thereby exposing the upper surface of the resist underlayer film on which the pattern has been formed. (V-9) A step of removing the resist interlayer or hard mask interlayer remaining on the upper surface of the resist underlayer by dry etching. (V-10) A step of removing the resist underlayer film on which the exposed surface pattern is formed by dry etching, and forming an inverted pattern of the original pattern on the metal-containing film. (V-11) A process of processing the workpiece substrate using the metal-containing film on which the inverted pattern is formed as a mask to form the inverted pattern on the workpiece substrate. The present invention provides a pattern forming method characterized by having the following features.

[0046] The pattern formation method using the inversion process described above allows for the formation of fine patterns on the workpiece with even greater precision.

[0047] In this case as well, it is preferable to form the inorganic hard mask interlayer by CVD or ALD.

[0048] When the above inorganic hard mask is formed by CVD or ALD, fine patterns can be formed on the workpiece with higher precision. [Effects of the Invention]

[0049] As explained above, the metal-containing film-forming compound of the present invention is a compound represented by the general formula (M) above, so during baking, radicals are generated by radical cleavage of the Sn-alkyl bond, and a crosslinking reaction occurs due to these radicals. Furthermore, since tin is bonded to the units having catechol or diol, multiple tin atoms can be introduced into one molecule, thereby increasing the tin content. Moreover, in the general formula (M) above, when n2 is 1 or when n1 is 2 and T is different, the molecular symmetry is broken, which can increase solvent solubility. Therefore, compositions using the compound of the present invention can provide a resist underlayer film material with excellent solvent solubility and a high tin content. In particular, in the fine patterning process using the multilayer resist method in semiconductor device manufacturing processes, it is possible to embed the pattern without producing defects such as voids or peeling, even on workpiece substrates that have areas that are difficult to embed / planarize, such as densely packed areas of high aspect ratio fine pattern structures represented by miniaturized DRAM memory. Furthermore, because it has superior dry etching resistance compared to conventional coated organic resist underlayer materials, it is possible to form fine patterns on the workpiece with even greater precision compared to organic resist underlayers. Furthermore, the metal-containing film-forming composition containing the metal-containing film-forming compound of the present invention contains tin atoms, which have high EUV light absorption, resulting in a sensitizing effect due to secondary electrons generated from them during exposure. Moreover, because tin atoms have a large atomic weight, they have a high effect in suppressing acid diffusion from the upper resist layer into the lower resist layer, thus enabling high sensitivity while maintaining the LWR performance inherent in the upper resist layer. [Brief explanation of the drawing]

[0050] [Figure 1] This is an explanatory diagram of an example of the pattern formation method of the present invention (3-layer resist process). [Figure 2] This is an explanatory diagram illustrating an example of the tone inversion pattern formation method of the present invention (inversion of the SOC pattern of a 3-layer resist process). [Figure 3] This is an explanatory diagram of the embedding characteristics evaluation method. [Modes for carrying out the invention]

[0051] As described above, in a fine patterning process using a multilayer resist method, there has been a need for the development of a metal-containing film-forming composition with excellent film-forming properties, and a metal-containing film-forming compound useful for this composition, which can be used to form a resist underlayer film that can transfer the resist pattern to the substrate with higher precision.

[0052] The inventors focused on organotin compounds, which are expected to play a significant role in the EUV lithography generation, and conducted extensive research. As mentioned above, tin atoms, which have high EUV light absorption, have a sensitizing effect due to secondary electrons generated during lithography, and have the characteristic of being able to increase sensitivity while maintaining the LWR performance inherent in the resist upper layer film. On the other hand, organotin compounds that have been considered as resist upper layers have poor heat resistance and undergo rapid volume shrinkage during baking, making it difficult to form a uniform film or fill in steps on the substrate when baked at high temperatures. The inventors considered that by reacting an organic molecule having a diol structure (including catechol) and a carboxylate in its molecule with a tin compound, it is possible to increase the molecular weight while introducing multiple tin atoms into the molecule, and even if the bond is broken during baking, there is a high possibility that a sufficient molecular weight can be maintained, sublimation can be suppressed, heat resistance can be improved, and excellent film formation properties can be exhibited. Furthermore, since multiple tin atoms can be introduced into a single molecule, it is possible to increase not only heat resistance but also tin content, resulting in a metal-containing film-forming composition that exhibits excellent etching resistance. Therefore, the inventors conducted further intensive studies and discovered that a metal-containing film-forming compound represented by the above general formula (M) exhibits excellent film-forming properties and can also increase the tin content, resulting in a metal-containing film-forming compound with excellent etching resistance, thus completing the present invention.

[0053] In other words, the present invention relates to a metal-containing film-forming compound that can be used in a metal-containing film-forming composition that functions as a resist underlayer material used in semiconductor manufacturing, characterized in that the compound is represented by the following general formula (M). [ka] (In the above general formula (M), T is independently of the following general formula (T-1) or (T-2), P is independently of *OCOR (* represents a bond with a Sn atom, and R represents a monovalent organic group), and Q is independently of a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 aliphatic unsaturated hydrocarbon group containing one or more double or triple bonds, or a substituted or unsubstituted carbon The elements are aryl groups with 6 to 30 carbon atoms, substituted or unsubstituted arylalkyl groups with 7 to 31 carbon atoms, halogen atoms, and alkoxy groups with 1 to 20 carbon atoms. Furthermore, n1, n2, and n3 are integers satisfying n1≧1, n2≧0, and n3≧1, and n1+n2+n3=4. When n1≧2, T may be the same or different; when n2=2, P may be the same or different; and when n3≧2, Q may be the same or different. [ka] (In the above general formulas (T-1) and (T-2), R1 is a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 aliphatic unsaturated hydrocarbon group containing one or more double or triple bonds, a substituted or unsubstituted C6-C30 aryl group, or a substituted or unsubstituted C7-C31 arylalkyl group, and * is the bond with the Sn atom in the above general formula (M). W1 is a substituted or unsubstituted C1-C40 linear, branched or cyclic saturated or unsaturated hydrocarbon group (including aromatic ring 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, or may form a heterocyclic structure via the heteroatom. R2 is a substituted or unsubstituted C1-C20 alkyl group, or a substituted or unsubstituted s1 represents a 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 or triple bonds, a hydroxyl group, an amino group, or a halogen atom, where s1 is an integer from 0 to 1 and m is an integer from 0 to 1. W2 is a substituted or unsubstituted linear, branched, or cyclic saturated or unsaturated hydrocarbon group (including aromatic ring groups) having 1 to 40 carbon atoms, and the hydrocarbon group may contain 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, or a heterocyclic structure via the heteroatom. s2 is an integer from 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 having 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, it forms a carbonyl group, and W2 and R3 may bond to each other to form a ring structure.

[0054] The present invention will be described in detail below, but is not limited to these descriptions. Although catechol (1,2-benzenediol) is included in the category of diols, in this specification, compounds having a 1,2-benzenediol structure are referred to as catechol, and other diols are sometimes simply referred to as "diols."

[0055] <Compounds for forming metal-containing films> The metal-containing film-forming compound of the present invention is characterized by being represented by the following general formula (M). The compound can be used in a metal-containing film-forming composition that functions as a resist underlayer material used in semiconductor manufacturing. [ka] (In the above general formula (M), T is independently of the following general formula (T-1) or (T-2), P is independently of *OCOR (* represents a bond with a Sn atom, and R represents a monovalent organic group), and Q is independently of a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 aliphatic unsaturated hydrocarbon group containing one or more double or triple bonds, or a substituted or unsubstituted carbon The elements are aryl groups with 6 to 30 carbon atoms, substituted or unsubstituted arylalkyl groups with 7 to 31 carbon atoms, halogen atoms, and alkoxy groups with 1 to 20 carbon atoms. Furthermore, n1, n2, and n3 are integers satisfying n1≧1, n2≧0, and n3≧1, and n1+n2+n3=4. When n1≧2, T may be the same or different; when n2=2, P may be the same or different; and when n3≧2, Q may be the same or different. [ka] (In the above general formulas (T-1) and (T-2), R1 is a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 aliphatic unsaturated hydrocarbon group containing one or more double or triple bonds, a substituted or unsubstituted C6-C30 aryl group, or a substituted or unsubstituted C7-C31 arylalkyl group, and * is the bond with the Sn atom in the above general formula (M). W1 is a substituted or unsubstituted C1-C40 linear, branched or cyclic saturated or unsaturated hydrocarbon group (including aromatic ring 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, or may form a heterocyclic structure via the heteroatom. R2 is a substituted or unsubstituted C1-C20 alkyl group, or a substituted or unsubstituted s1 represents a 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 or triple bonds, a hydroxyl group, an amino group, or a halogen atom, where s1 is an integer from 0 to 1 and m is an integer from 0 to 1. W2 is a substituted or unsubstituted linear, branched, or cyclic saturated or unsaturated hydrocarbon group (including aromatic ring groups) having 1 to 40 carbon atoms, and the hydrocarbon group may contain 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, or a heterocyclic structure via the heteroatom. s2 is an integer from 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 having 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, it forms a carbonyl group, and W2 and R3 may bond to each other to form a ring structure.

[0056] In the above general formula (M), P is independently *OCOR (* represents the bond with the Sn atom, and R represents a monovalent organic group), and R can be, for example, linear hydrocarbon groups such as methyl, ethyl, or n-butyl groups, branched hydrocarbon groups such as isopropyl or tert-butyl groups, cyclic hydrocarbon groups such as cyclohexane or cyclopropane, as well as other groups such as ethers, esters, amides, aryl groups, arylalkyl groups, or groups containing unsaturated bonds. These may be substituted or unsubstituted, and are not particularly limited as long as they are groups derived from monovalent carboxylic acids. From the viewpoint of crosslinking, it is preferable to include a structure in which an unsaturated bond, a hydroxyl group, or a protecting group is removed by heat or acid to generate a hydroxyl group or carboxyl group. In the following, we may use "n" to indicate a primary alkyl group, or "s," "t," or "sec-" and "tert-" to indicate secondary and tertiary alkyl groups, respectively.

[0057] In the above general formula (M), Q is independently a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 aliphatic unsaturated hydrocarbon group containing one or more double or triple bonds, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C7-C31 arylalkyl group, a halogen atom, or a C1-C20 alkoxy group. From the viewpoint 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. Furthermore, 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 of the above general formula (T-1) or (T-2), and in general formulas (T-1) to (T-2), R1 is preferably a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 aliphatic unsaturated hydrocarbon group containing one or more double or triple bonds, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C7-C31 arylalkyl group, 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, and more preferably an n-butyl group. Furthermore, considering the ease of radical cleavage of the Sn-alkyl bond, a t-butyl group and a benzyl group are also preferred.

[0059] In the above general formula (M), n1, n2, and n3 are integers satisfying n1≧1, n2≧0, and n3≧1, and n1+n2+n3=4. When n1≧2, T may be the same or different; when n2=2, P may be the same or different; and when n3≧2, Q may be the same or different. From the viewpoint of increasing the tin content, it is preferable that n1=3 and n3=1, and from the viewpoint of breaking the molecular symmetry and increasing solubility, it is preferable that n1=2, n2=1, and n3=1.

[0060] In the above general formula (T-1), W1 is a substituted or unsubstituted linear, branched, or cyclic saturated or unsaturated hydrocarbon group (including aromatic groups) having 1 to 40 carbon atoms. The hydrocarbon group may contain oxygen, nitrogen, or sulfur atoms as heteroatoms and may form ether bonds, carbonyl groups, ester groups, or amide groups. It may also form a heterocyclic structure via the heteroatoms, such as via amide or ester groups. However, from the viewpoint of heat resistance and increased Sn content, it is preferable that W1 is a linear, branched, or cyclic saturated or unsaturated hydrocarbon group having 1 to 20 carbon atoms (the hydrocarbon group may contain oxygen, nitrogen, or sulfur atoms as heteroatoms and may form ether bonds, carbonyl groups, or ester groups). s1 is an integer from 0 to 1. From the viewpoint of increasing tin content, s1 is preferably 0, and from the viewpoint of thermal fluidity and embedding properties, it is preferable that an organic chain is included, so s1 is preferably 1. When s1 is 0, it means that the carbonyl group is single-bonded.

[0061] More specifically, W1 is preferably 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 may contain an oxygen atom, a nitrogen atom, or a sulfur atom as heteroatoms, 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). [ka] (In the above general formulas (W1-1) to (W1-4), R W (#1 and #2 represent the ester and benzene ring bonds, respectively, as they are divalent organic groups with 1 to 23 carbon atoms.)

[0062] In the above general formula (T-1), R2 is a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 aliphatic unsaturated hydrocarbon group containing one or more double 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 equation (T-1) are given below, but are not limited to these. (In the following equations, R1, R w (This represents the same base as above.) [ka]

[0064] In the above general formula (T-2), W2 is a substituted or unsubstituted linear, branched, or cyclic saturated or unsaturated hydrocarbon group (including aromatic groups) having 1 to 40 carbon atoms, 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, an ester group, or an amide group, or may form a heterocyclic structure via an amide group, an ester group, etc. However, from the viewpoint of heat resistance and increased Sn content, it is preferable that W2 is a linear, branched, or cyclic saturated or unsaturated hydrocarbon group (including aromatic groups) having 1 to 20 carbon atoms, which 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, it is preferable that W2 is a linear, branched, or cyclic saturated or unsaturated hydrocarbon group (including aromatic ring groups) having 1 to 10 carbon atoms, 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 any of the groups represented by the following general formulas (W2-1) to (W2-4). [ka] (In the above general formulas (W2-1) to (W2-4), R W (#1 and #2 represent the ester group and the bond to the carbon atom, respectively, as they are divalent organic groups with 1 to 23 carbon atoms.)

[0066] In the above general formula (T-2), 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, which together with the carbon atom to which it is bonded forms a carbonyl group. W2 and R3 may bond to each other, forming a ring structure. s2 is an integer from 0 to 1. From the viewpoint of increasing the tin content, s2 is preferably 0, and from the viewpoint of thermal fluidity and embedding properties, it is preferable to include an organic chain, so s2 is preferably 1. When s2 is 0, it means that the carbonyl group is single-bonded.

[0067] The following are some specific examples of (T-2) including W2, but are not limited to these. (In the following equation, R 1. R w (This represents the same base as above.) [ka]

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

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

[0070] A metal-containing film-forming compound with such a structure can further improve its thermosetting properties.

[0071] Furthermore, in the above general formulas (W1-1) to (W1-4) and (W2-1) to (W2-4), R W It is more preferable from the viewpoint of improving thermosetting properties and tin content that the structure is represented by the following general formula (1). [ka] (In the above 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. R a and R b These may be bonded, forming a cyclic substituent. (*1 and *2 represent the bond with the carbonyl group, but *1 and *2 may be reversed.)

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

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

[0074] (Reaction 1) Condensation occurs when 3 equivalents of (T) are added to alkyltin trichloride (Z). [ka]

[0075] (Reaction 2) When condensation occurs by adding 2 equivalents of (T) to dialkyltin dichloride (Z). [ka]

[0076] (Reaction 3) When condensation occurs by adding 1 equivalent each of (T) and (P) to dialkyltin oxide (Z). [ka]

[0077] (Reaction 4) When alkyltin trichloride (Z) is condensed with 2 equivalents of (T) and 1 equivalent of (P). [ka]

[0078] Furthermore, when synthesizing using multiple types of (T) or when (P) is used in the reaction in addition to (T), there are (M) molecules in which all (T) are of the same type, and (M) molecules in which all (T) are different. Therefore, n1 and n2 indicate the relative abundance of that substituent in the reaction system. For example, when alkyltin trichloride (1 equivalent) is used as (Z), acrylic acid (1 equivalent) is used as (P), and the following starting materials (2 equivalents) are used as (T), there are molecules in which all (T):(P) = 2:1, and overall the abundance ratio is similar to the initial charge ratio. [ka]

[0079] Furthermore, the compound represented by the unit (T) in the above general formula (M) can be synthesized by condensing one equivalent each of a tin compound such as dialkyltin dichloride or dialkyltin oxide (Z) and a compound (X) that contains both adjacent hydroxyl groups (two hydroxyl groups separated by two carbon atoms) and a carboxylic acid (reactions A1 and 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) [ka]

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

[0082] The condensation reactions using (T), (Z), and (P) described above (Reactions 1-4), as well as the condensation reaction using (X) and (Z) (Reaction A (Reactions A1, A2)), can usually be carried out without a solvent or in a solvent at room temperature or under cooling or heating as necessary. Examples of solvents that can be 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 individually or in combination of two or more types. These solvents can be used in amounts ranging from 0 to 3000 parts by mass per 100 parts by mass of the reaction raw materials. Furthermore, the reaction temperature is preferably between -50°C and the boiling point of the solvent, and more preferably between room temperature and 130°C.

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

[0084] The condensation reaction method for reaction A includes charging (X), (Z), solvent, and catalyst all at once, adding (Z) dropwise to the presence of (X), solvent, and catalyst, or adding the catalyst dropwise to the presence of (X), (Z), and solvent. The amount of (Z) used at this time is preferably 0.95 to 1.05 equivalents relative to (X), and more preferably 1.0 equivalent. After the condensation reaction of reaction A is complete, additional steps can be added to remove unreacted raw materials, catalyst, etc., such as raising the temperature of the reaction vessel to 130 to 230°C and removing volatile components at about 1 to 50 mmHg, or fractionating the obtained compound from impurities using an appropriate poor solvent or good solvent. After the completion of reaction A, reaction 3 or 4 can be carried out by adding additional (Z) or (P) to the reaction system. After the completion of the condensation reaction of reaction 3 or 4, an additional step can be added to remove impurities, etc., in the same manner as the purification method described above.

[0085] In the above general formula (M), P is *-OC(=O)R (where R is a monovalent organic group and * represents the bond with the Sn atom). When P is included, R can be freely changed, so by incorporating bulky structures, improvements in solubility and thermal fluidity can be expected. Furthermore, it is possible to create cross-linked structures, which can suppress sublimation and reduce volume shrinkage that induces deterioration of embedding properties. Examples of carboxylic acid raw materials containing R include linear substituted or unsubstituted hydrocarbon groups such as acetic acid, propionic acid, and glycine; branched substituted or unsubstituted hydrocarbon groups such as pivalic acid and 2-aminoisobutyric acid; and cyclic substituted or unsubstituted hydrocarbon groups such as cyclopropanecarboxylic acid and 3,3-difluorocyclobutanecarboxylic acid. Having There are no particular restrictions on monofunctional carboxylic acids, but from the viewpoint of thermosetting properties, it is more preferable that the group contains an unsaturated hydrocarbon group, a hydroxyl group, or a group in which the protecting group is removed by heat or acid to generate a hydroxyl group or a carboxyl group.

[0086] Furthermore, R is preferably 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). [ka] (In the above general formulas (A-1) to (A-4), Y A1 , Y A2 Each of these may be the same or different from the others, and may be a substituted or unsubstituted saturated or unsaturated divalent organic group (such as an aliphatic hydrocarbon group) having 1 to 23 carbon atoms, 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. A R is a hydrogen atom, a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms and saturated or 2 to 20 carbon atoms and 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. A1 This is an organic group represented by the following general formula (2) in which a protecting group is removed by the action of either an acid, heat, or both, generating one or more hydroxyl groups or carboxyl groups, and * represents the bond with the carbonyl group. [ka] (In the above general formula (2), R A2 * is an organic group whose protecting group is removed by the action of acid, heat, or both, and * is Y A1 Or Y A2 (This represents the connection point.)

[0087] In the above general formulas (A-1) to (A-4), Y A1 , Y A2 Each of these may be the same or different from the others, and is a substituted or unsubstituted saturated or unsaturated divalent organic group having 1 to 23 carbon atoms (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. A R is a hydrogen atom, a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms and saturated or 2 to 20 carbon atoms and 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. A1This is an organic group represented by the above general formula (2) in which a protecting group is removed by the action of either or both of an acid and / or heat, generating one or more hydroxyl groups or carboxyl groups. Considering thermal fluidity and solubility, it is preferably (A-4), and from the viewpoint of suppressing sublimation by organic decomposition that increases the tin content, it is preferably (A-1).

[0088] In the above general formulas (A-1) to (A-4), Y A1 , Y A2 A preferred structure could be, for example, the following, but it is not limited to these. (* in the formula below) a is R A1 The joint with, * b This represents the other connection point. [ka]

[0089] In the above general formula (A-3), R A The group is a hydrogen atom, a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms (saturated or 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. From the viewpoint of suppressing sublimation and increasing the Sn content, a hydrogen atom is preferred.

[0090] In the above general formula (2), R A2 The organic group is one whose protecting group (thermally acid-unstable group) is removed by the action of acid, heat, or both. Preferably, it is a tertiary hydrocarbyl group or a group that forms an acetal structure with an adjacent oxygen atom, and a tertiary hydrocarbyl group is particularly preferred.

[0091] The tertiary hydrocarbyl group is preferably one having 4 to 20 carbon atoms, and the tert-butyl group is particularly preferred from the viewpoint of suppressing sublimation by thermal decomposition products and ease of raw material procurement. Specific examples are listed below, but are not limited to these. In the following formulas, * represents a bond with an oxygen atom. [ka]

[0092] [ka]

[0093] [ka]

[0094] [ka]

[0095] Specific examples of groups that form the acetal structure are, but are not limited to, those listed below. In the following formulas, * represents a bond with an oxygen atom. [ka]

[0096] [ka]

[0097] [ka]

[0098] Such metal-containing film-forming compounds exhibit excellent solvent solubility and thermal fluidity. A1Because it contains organic groups whose protecting groups are removed by the action of bulky acid, heat, or both, when used in a metal-containing film-forming composition, these groups are removed during baking, increasing the tin content and resulting in a metal-containing film-forming compound with excellent dry etching resistance. Furthermore, the hydroxyl and carboxyl groups generated by the removal readily react with radicals generated by the cleavage of the tin-carbon bond during baking due to the presence of terminal OH groups and α-hydrogens, causing a crosslinking reaction. This results in excellent thermosetting properties, suppressing volume shrinkage, and providing a metal-containing film-forming composition, such as a resist underlayer material, with excellent film-forming and embedding properties even after high-temperature baking.

[0099] [ka] (In the above 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 bond with the carbonyl group.) [ka] (In the above general formula (B), Y B R is a substituted or unsubstituted saturated or unsaturated divalent organic group having 1 to 20 carbon atoms (such as an aliphatic hydrocarbon group), 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. B (This is either a hydroxyl group or one of the structures shown in the following general formulas (B-1) to (B-3).) [ka] (In the above general formulas (B-1) to (B-3), R B1 is a hydrogen atom or a monovalent organic group with 1 to 10 carbon atoms, q represents 0 or 1, and * represents Y B (This represents the connection point.)

[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 bond with the carbonyl group. In the above general formula (B), Y BR is a substituted or unsubstituted saturated or unsaturated divalent organic group having 1 to 20 carbon atoms (such as an aliphatic hydrocarbon group), 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. B It is preferable that R is a hydroxyl group or one of the structures represented by the above general formulas (B-1) to (B-3). Also, in the above general formulas (B-1) to (B-3), B1 This 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] Preferred structures for the above general formula (B) include, but are not limited to, the following structures. In the following formula, * represents a bond with a carbonyl group. [ka]

[0102] Such metal-containing film-forming compounds exhibit excellent solvent solubility and thermal fluidity. B Because it contains hydroxyl groups or unsaturated bonds, when used in a metal-containing film-forming composition, these undergo a crosslinking reaction during baking, resulting in excellent thermosetting properties. Furthermore, the crosslinking reaction is promoted by reaction with radicals generated by the cleavage of tin-carbon bonds, and because of its excellent thermosetting properties, volume shrinkage can be suppressed. This allows for the provision of a metal-containing film-forming composition with excellent film-forming and embedding properties even after high-temperature baking.

[0103] [ka] (In the above general formula (4), X is a divalent organic group having 1 to 31 carbon atoms, C is one of the general formulas (C-1) to (C-4) below, and * represents the bond with the carbonyl group.) [ka] (In the above general formulas (C-1) and (C-3), R C1R is a hydrogen atom or a methyl group, and they may be the same or different from each other in the same formula. In (C-3) and (C-4), R C2 This refers to a hydrogen atom or a substituted or unsubstituted saturated or unsaturated monovalent organic group with 1 to 20 carbon atoms (such as an aliphatic hydrocarbon group), a substituted or unsubstituted aryl group with 6 to 30 carbon atoms, or a substituted or unsubstituted arylalkyl group with 7 to 31 carbon atoms. * indicates a bond with a carbonyl group.

[0104] In the above general formula (4), X is a divalent organic group having 1 to 31 carbon atoms, specifically a substituted or unsubstituted saturated or unsaturated divalent hydrocarbon group having 1 to 20 carbon atoms or 2 to 20 carbon atoms, or a substituted or unsubstituted allium group having 6 to 30 carbon atoms. Ren arylalkyl groups, substituted or unsubstituted, with 7 to 31 carbon atoms. Ren Examples include the group. C is a group represented by the general formulas (C-1) to (C-4) above, and in (C-1) and (C-3), R C1 From the viewpoint of thermal fluidity, a methyl group is preferred, and from the viewpoint of curability, a hydrogen atom is preferred. Also, R in (C-3) and (C-4) C2 From the viewpoint of thermal fluidity, the above-described structure other than hydrogen atoms is preferred.

[0105] In the above general formulas (C-1) to (C-4), R C2 Preferred structures include, but are not limited to, the following. In the following formulas, * represents a bond with a nitrogen atom. [ka]

[0106] A metal-containing film-forming compound having such a structure contains the organic group represented by the general formula (3) above, resulting in a metal-containing film-forming compound with excellent solvent solubility and heat resistance. Furthermore, because it contains one of the structures represented by the general formulas (C-1) to (C-4) above at its terminal end, it has a high crosslinking group density, which reduces rapid volume shrinkage during baking, thus providing a metal-containing film-forming composition with excellent film-forming and embedding properties.

[0107] A metal-containing film formed using a composition containing a metal-containing film-forming compound (M) exhibits the following characteristics during baking: Sn-C bonds Solution Radicals are generated as the atoms separate, and the curing reaction proceeds due to the generated radicals (Equation 1). Therefore, recombination of radicals is necessary to promote the curing reaction, which can require time for curing or to increase the efficiency of radical generation at high temperatures. However, since the compound of the present invention contains multiple tin atoms in one molecule, there are many active species, and radical generation and recombination occur efficiently, resulting in excellent heat resistance and thermosetting properties, and thus providing a resist underlayer film with excellent film-forming properties. Furthermore, if groups containing unsaturated bonds or hydroxyl groups are present in P, these not only react with radicals, but also undergo crosslinking reactions on their own (Equation 2), resulting in a film with even better heat resistance and thermosetting properties.

[0108] [ka]

[0109] [ka]

[0110] In the above general formulas (A-1) to (A-4), Y A1 Preferred structures for X in general formula (2) or general formula (3) include, but are not limited to, the following structures. In the following formulas, * represents the bond between the carbonyl group and the carbon atom, or * in formulas (A-1) to (A-4), formula (3), and formula (4). [ka]

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

[0112] Y in the above general formulas (A-1) to (A-4) A1 If X in the above general formula (3) or X in the above general formula (4) 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] Also, Y in the above general formulas (A-1) to (A-4) A1 If X in the above general formula (3) or X in the above general formula (4) is the following general formula (1), a metal-containing film-forming compound can be provided.

Chemical formula

[0114] The carboxylic acid raw material containing the above general formula (1) can be synthesized by ring-opening an acid anhydride. However, when an asymmetric anhydrous carboxylic acid is ring-opened, it becomes a mixture of two kinds, 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 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 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., degree of dispersion) of the metal-containing film-forming compound, measured by gel permeation chromatography (GPC) using tetrahydrofuran, is preferably within the range of 1.00 ≤ Mw / Mn ≤ 1.80, and more preferably within the range of 1.00 ≤ Mw / Mn ≤ 1.50. By definition, a monomolecule compound has an Mw / Mn of 1.00, but due to the separation capabilities of GPC, the measured value may exceed 1.00. Generally, polymers with repeating units are extremely difficult to approach Mw / Mn = 1.00 unless a special polymerization method is used, and they have a distribution of Mw, resulting in an Mw / Mn value greater than 1. In this invention, 1.00 ≤ Mw / Mn ≤ 1.50 is defined as an index indicating monomolecule nature in order to distinguish between monomolecule compounds and polymers. The above index can also be applied to mixtures of two or more metal-containing film-forming compounds.

[0117] <Metal-containing film forming composition> Furthermore, the present invention provides a metal-containing film-forming composition that functions as a resist underlayer material used in semiconductor manufacturing, and is characterized by containing (a) the above-mentioned metal-containing film-forming compound and (b) an organic solvent.

[0118] Such metal-containing film-forming compositions contain organotin compounds with excellent heat resistance and thermal fluidity, and can form metal-containing films such as resist underlayers that have superior dry etching resistance compared to conventional organic underlayer materials, as well as advanced embedding / planarization properties.

[0119] The following describes the components included in the metal-containing film-forming composition of the present invention other than the metal-containing film-forming compound described above (a).

[0120] (b) Organic solvents The (b) organic solvent that can be used in the metal-containing film-forming composition of the present invention is not particularly limited, as long as it dissolves or disperses the above-mentioned (a) metal-containing film-forming compound, (c) crosslinking agent, (d) surfactant, (e) fluidity enhancer, (f) acid generator, and other additives.

[0121] Specifically, organic solvents described in paragraphs

[0091] to

[0092] of Japanese Patent Publication 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, are preferably used.

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

[0123] As for the high-boiling point solvent, there are no particular restrictions on hydrocarbons, alcohols, ketones, esters, ethers, chlorinated solvents, etc., as long as it can dissolve each component of the metal-containing film-forming composition of the present invention. 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 Dibutyl 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 include 6-hexanediol diacetate, triethylene glycol diacetate, γ-butyrolactone, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, dihexyl malonate, diethyl succinate, dipropyl succinate, dibutyl succinate, dihexyl succinate, dimethyl adipate, diethyl adipate, and dibutyl adipate, which may be used individually or in combination.

[0124] The high-boiling point solvent can be appropriately selected from the above-mentioned options, for example, according to the temperature at which the resist underlayer film formation composition is heat-treated. 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 risk of excessive volatilization during baking (heat treatment), so sufficient thermal fluidity can be obtained during film formation, and it is believed that a resist underlayer film with excellent embedding / planarization properties can be formed. Furthermore, with such a boiling point, there is no risk of residual solvent remaining in the film after baking without volatilization, so there is no risk of adverse effects on film properties such as etching resistance.

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

[0126] Furthermore, when using a high-boiling-point solvent, the blending amount is preferably 1 to 30 parts by mass per 100 parts by mass of an organic solvent with a boiling point of less than 180°C. This blending amount is preferable because it provides sufficient thermal fluidity during baking, does not remain in the film, and does not lead to deterioration of film properties such as etching resistance.

[0127] <Composition for forming a resist underlayer film> The above composition is a metal-containing film formation composition that can be used as a resist underlayer film in a multilayer resist method, and can further contain one or more of (c) a crosslinking agent, (d) a surfactant, (e) a fluidity enhancer, and (f) an acid generator. The following describes the components included in the resist underlayer film forming composition other than (a) the metal-containing film forming compound and (b) the organic solvent.

[0128] [(c) Crosslinking agent] The above resist underlayer film forming composition may further contain (c) a crosslinking agent in order to enhance the density of the film and further suppress 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. Examples include melamine-based crosslinking agents, acrylate-based crosslinking agents, glycoluryl-based crosslinking agents, benzoguanamine-based crosslinking agents, urea-based crosslinking agents, β-hydroxyalkylamide-based crosslinking agents, isocyanurate-based crosslinking agents, aziridine-based crosslinking agents, oxazoline-based crosslinking agents, phenol-based crosslinking agents (e.g., methylol or alkoxymethyl type crosslinking agents of polynuclear phenols), epoxy-based crosslinking agents, and oxetane-based crosslinking agents. The content of the (c) crosslinking agent is preferably 5 to 50 parts by mass, more preferably 10 to 40 parts by mass, per 100 parts by mass of the (a) metal-containing film forming compound.

[0129] Examples of melamine-based crosslinking agents include hexamethoxymethylated melamine, hexasubtoxicmethylated melamine, alkoxy and / or hydroxy-substituted derivatives thereof, and partially self-condensed derivatives thereof. As an example of an acrylate-based crosslinking agent, dipentaerythritol hexaacrylate can be cited. Examples of glycoluryl crosslinking agents include tetramethoxymethylated glycoluryl, tetrabutoxymethylated glycoluryl, their alkoxy and / or hydroxy substituted derivatives, and their partial self-condensates. Examples of benzoguanamine-based crosslinking agents include tetramethoxymethylated benzoguanamine, tetrabutoxymethylated benzoguanamine, their alkoxy and / or hydroxy-substituted derivatives, and their partial self-condensed derivatives. As the urea-based crosslinking agent, specifically, dimethoxymethylated dimethoxyethyleneurea, its alkoxy and / or hydroxy-substituted derivatives, and their partial self-condensates can be exemplified. As the β-hydroxyalkylamide-based crosslinking agent, specifically, N,N,N’,N’-tetrakis(2-hydroxyethyl) adipic acid amide can be exemplified. As the isocyanurate-based crosslinking agent, specifically, triglycidyl isocyanurate, triallyl isocyanurate can be exemplified. As the aziridine-based crosslinking agent, specifically, 4,4’-bis(ethyleneiminocarbonylamino) diphenylmethane, 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), 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 a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a pentyl group, an isopentyl group, a hexyl group, an octyl group, an ethylhexyl group, a decyl group, and an eicosanyl group, and a hydrogen atom or a methyl group is preferred.

[0132] As examples of the compound represented by the above 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] While the above compounds are commercially available, epoxy crosslinking agents and oxetane crosslinking agents can also be obtained by reacting a hydroxyl group with epibromohydrin or 3-bromomethyloxetane, as shown in the following formula. In the formula below, R5 is a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms in a saturated state or 2 to 20 carbon atoms in an unsaturated state, 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. Based It is possible to leave all hydroxyl groups unreacted. In this case, it is preferable that the number of epoxy + oxetane groups > the number of hydroxyl groups, and more preferably the number of epoxy + oxetane groups > the number of hydroxyl groups × 2. The content of these compounds is preferably 5 to 50 parts by mass, and more preferably 10 to 40 parts by mass, per 100 parts by mass of the metal-containing film-forming compound (a). [ka]

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

[0137] Furthermore, as polymer types, specifically, polymers in which the mole fraction of repeating units represented by the following general formulas (XL-2) and (XL-3) is 20% or more are mentioned. If the total mole fraction of the structural units represented by general formulas (XL-2) and (XL-3) does not equal 100%, other structural units may include α,β-unsaturated carboxylic acid esters such as other acrylic acid esters, other methacrylic acid esters, other acryl acid amides, other methacrylic acid amides, crotonic acid esters, maleic acid esters, and itaconic acid esters; α,β-unsaturated carboxylic acids such as methacrylic acid, acrylic acid, maleic acid, and itaconic acid; acrylonitrile; methacrylonitrile; α,β-unsaturated lactones such as 5,5-dimethyl-3-methylene-2-oxotetrahydrofuran; norbornene derivatives, tetracyclo[4.4.0.1 2,5 .1 7,10 ]Cyclic olefins such as dodecene derivatives; α,β-unsaturated carboxylic acid anhydrides such as maleic anhydride and itaconic anhydride; allyl ethers; vinyl ethers; vinyl esters; and vinylsilanes can be used in combination. Furthermore, these polymers preferably have a weight-average molecular weight of 1,000 to 20,000 and a GPC dispersion degree (Mw / Mn) of 2.0 or less. Furthermore, the content of these compounds is as described above ( a The amount of the metal-containing film-forming compound is preferably 5 to 50 parts by mass, and more preferably 10 to 40 parts by mass, per 100 parts by mass. The molecular weight and dispersion can be determined by calculating the weight-average molecular weight (Mw) and number-average molecular weight (Mn) in polystyrene terms using GPC with tetrahydrofuran as the eluent, and then determining the dispersion (Mw / Mn).

[0138] [ka] (In the formula, R7 is a hydrogen atom or a methyl group, R8 is a hydrogen atom or a group selected from formulas (2-1) to (2-3) below, and L1 represents a divalent organic group containing a single bond, -C(=O)O-, -C(=O)NH-, or -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 perspective of curability, and more preferably, the number of groups of (2-1) to (2-3) > 2 × the number of hydrogen atoms.

Chemical formula

Chemical formula

[0140] <(d) Surfactant> In the above composition for forming a resist lower layer film, (d) a surfactant can be added to improve the coating property 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 above composition for forming a resist lower layer 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')-spirovidene-6,6'-diol, 3,3,3',3'-tetramethyl-2,3,2',3'-tetrahydro-(1,1')-spirovidene-6,6'-diol, 3,3,3',3',4,4'-hexamethyl-2,3,2',3'-tetrahydro-(1,1')-spirovidene-6,6'-diol, 2,3,2',3'-tetrahydro-(1,1')-spirovidene-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 Examples include novolac resins such as bisphenol, trisphenol, dicyclopentadiene, tetrahydroindene, 4-vinylcyclohexene, norbornadiene, 5-vinylnorborna-2-ene, α-pinene, β-pinene, and limonene, as well as polyhydroxystyrene, polystyrene, polyvinylnaphthalene, polyvinylanthracene, polyvinylcarbazole, polyindene, polyacenaphthalene, polynorbornene, polycyclodecene, polytetracyclododecene, polynortricycline, poly(meth)acrylate, and copolymers thereof. Furthermore, naphthol dicyclopentadiene copolymer described in Japanese Patent Publication No. 2004-205685, fluorene bisphenol novolac resin described in Japanese Patent Publication No. 2005-128509, acenaphthylene copolymer described in Japanese Patent Publication No. 2005-250434, fullerene having a phenol group described in Japanese Patent Publication No. 2006-227391, bisphenol compound and novolac resin described in Japanese Patent Publication No. 2006-293298, novolac resin of adamantanephenol compound described in Japanese Patent Publication No. 2006-285095, bisnaphthol compound and novolac resin described in Japanese Patent Publication No. 2010-122656, fluorene compound described in Japanese Patent Publication No. 2017-119671, fullerene resin compound described in Japanese Patent Publication No. 2008-158002, etc., can also be blended. The amount of the above-mentioned fluidity enhancer is preferably 0.001 to 100 parts by mass, and more preferably 0.01 to 50 parts by mass, per 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] (In the formula, R 10 is a hydrogen atom or a saturated or unsaturated monovalent organic group having 1 to 30 carbon atoms which may be substituted. Y is a saturated or unsaturated divalent organic group having 2 to 30 carbon atoms.)

[0145] [Chemical formula] (In the formula, R 10a is an alkyl group having 1 to 4 carbon atoms. Y a is a saturated or unsaturated divalent hydrocarbon group having 4 to 10 carbon atoms and may have an ether bond. n represents the average number of repeating units and is 3 to 500.)

[0146] [(f) acid generator] In order to further accelerate 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 No. 2007-199653 can be added, but are not limited thereto.

[0147] The above acid generating agents can be used individually or in combination of two or more. When adding an acid generating agent, the amount added is preferably 0.05 to 50 parts by mass, more preferably 0.1 to 10 parts by mass, per 100 parts by mass of the above (a) metal-containing film-forming compound.

[0148] <Method for forming a resist underlayer film> The present invention provides a method for forming a packing film that functions as a resist underlayer film for multilayer resist films used in lithography or as a planarization film for semiconductor manufacturing, using the above-described metal-containing film-forming composition.

[0149] In the resist underlayer film formation method using the metal-containing film-forming composition of the present invention, the above-mentioned metal-containing film-forming composition is coated onto 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 resist interlayer film. Baking is preferably performed at a temperature of 100°C to 600°C for 10 to 600 seconds, and more preferably at a temperature of 200°C to 500°C for 10 to 300 seconds. Considering the impact on device damage and wafer deformation, the upper limit of the heating temperature in the lithography wafer process is preferably 600°C or less, and more preferably 500°C or less.

[0150] Furthermore, in the resist underlayer film formation method using the metal-containing film-forming composition of the present invention, the metal-containing film-forming composition of the present invention can be coated onto a workpiece substrate by a spin coating method or the like, as described above, and the metal-containing film-forming composition can be cured by firing in an atmosphere with an oxygen concentration of 0.1% to 21% by volume to form a metal-containing film.

[0151] By firing the metal-containing film-forming composition of the present invention in such an oxygen atmosphere, a sufficiently hardened film can be obtained. While air may be used as the atmosphere during baking, it is preferable to seal in an inert gas such as N2, Ar, or He to reduce oxygen levels and prevent oxidation of the metal-containing film. 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 prevents increased absorption and reduced etching resistance.

[0152] <Method for forming patterns using a composition for forming a resist underlayer film> Furthermore, the present invention provides a pattern formation method using the above-mentioned metal-containing film forming composition, characterized by forming a metal-containing film on a workpiece substrate using the above-mentioned metal-containing film forming composition, forming a resist upper layer film on the metal-containing film using a photoresist material, pattern exposure of the resist upper layer film, developing with a developer to form a pattern on the resist upper layer film, transferring the pattern to the metal-containing film by dry etching using the resist upper layer film with the pattern formed on it as a mask, and processing the workpiece substrate using the metal-containing film with the pattern formed on it as a mask to form a pattern on the workpiece substrate.

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

[0154] Furthermore, the present invention provides a pattern formation method using a three-layer resist process with such a metal-containing film forming composition, characterized by: forming a metal-containing film on a workpiece substrate using the above-mentioned metal-containing film forming composition; forming a resist interlayer (silicon-containing resist interlayer) on the metal-containing film using a resist interlayer material such as a silicon-containing resist interlayer; forming a resist upper layer on the resist interlayer using a photoresist material; pattern exposure of the resist upper layer, followed by development with a developer to form a pattern on the resist upper layer; using the resist upper layer with the pattern formed on it as a mask to transfer the pattern to the resist interlayer by dry etching; using the resist interlayer with the transferred pattern as a mask to transfer the pattern to the metal-containing film by dry etching; and processing the workpiece substrate using the metal-containing film with the pattern formed on it as a mask to form a pattern on the workpiece substrate. The following description will explain the case in which a silicon-containing resist interlayer is used as the resist interlayer.

[0155] An example of a three-layer resist process is shown below using Figure 1. In the three-layer resist process, as shown in Figure 1(A), a metal-containing film (metal-containing resist underlayer) 3 is formed on a workpiece layer 2 laminated on a workpiece substrate 1 using the metal-containing film-forming composition of the present invention, then a silicon-containing resist interlayer 4 is formed, and finally a resist upper layer 5 is formed on top of it.

[0156] Next, as shown in Figure 1(B), the required portion (exposed portion) 6 of the resist upper layer 5 is exposed, and PEB and development are performed to form the resist upper layer pattern 5a (Figure 1(C)). Using this obtained resist upper layer pattern 5a as a mask, the silicon-containing resist interlayer 4 is etched using a CF-based gas to form the silicon-containing resist interlayer pattern 4a (Figure 1(D)). After removing the resist upper layer pattern 5a, the metal-containing film 3 is chlorine plasma etched using this obtained silicon-containing resist interlayer pattern 4a as a mask to form the metal-containing film pattern (metal-containing resist lower layer pattern) 3a (Figure 1(E)). Furthermore, after removing the silicon-containing resist interlayer pattern 4a, the workpiece layer 2 is etched using the metal-containing film pattern 3a as a mask to form pattern 2a on the workpiece layer (Figure 1(F)).

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

[0158] As the silicon-containing resist interlayer in the above three-layer resist process, a polysiloxane-based interlayer is also preferably used. By giving the silicon-containing resist interlayer an anti-reflective effect, reflection can be suppressed. In particular, for 193nm exposure, if a material containing many aromatic groups as an organic film and having high etching selectivity with the substrate is used, the k value will be high and substrate reflection will be high. However, by giving the silicon-containing resist interlayer an absorption that results in an appropriate k value, it is possible to suppress reflection, and substrate reflection can be reduced to 0.5% or less. As silicon-containing resist interlayers with an anti-reflective effect, anthracene is preferably used for 248nm and 157nm exposure, and polysiloxane is preferably used for 193nm exposure, with phenyl groups or absorbent groups having silicon-silicon bonds pendanted and crosslinked by acid or heat.

[0159] In addition, the present invention provides a pattern formation method using a four-layer resist process with such a metal-containing film forming composition, characterized by the steps of: forming a metal-containing film on a substrate using the above-mentioned metal-containing film forming composition; forming a silicon-containing resist interlayer on the resist underlayer using a silicon-containing resist interlayer material; forming an organic anti-reflective film (BARC) or adhesion film on the silicon-containing resist interlayer; forming a resist upper layer on the BARC using a photoresist material; pattern exposure of the resist upper layer, followed by development with a developer to form a pattern on the resist upper layer; using the resist upper layer with the pattern formed on it as a mask, transferring the pattern to the BARC or adhesion film and the silicon-containing resist interlayer by dry etching; using the silicon-containing resist interlayer with the transferred pattern as a mask, transferring the pattern to the metal-containing film by dry etching; and processing the substrate using the metal-containing film with the pattern formed on it as a mask to form a pattern on the substrate.

[0160] Alternatively, an inorganic hard mask may be formed instead of a silicon-containing resist underlayer film. In this case, at a minimum, a metal-containing film is formed on the workpiece using the metal-containing film-forming composition of the present invention, an inorganic hard mask selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film is formed on the metal-containing film, a resist upper layer film is formed on the inorganic hard mask using the photoresist composition to form a circuit pattern on the resist upper layer film, the inorganic hard mask is etched using the resist upper layer film on which the pattern is formed as a mask, the metal-containing film is etched using the inorganic hard mask on which the pattern is formed as a mask, and further, the workpiece is etched using the metal-containing film on which the pattern is formed as a mask to form a pattern on the workpiece, thereby forming a semiconductor device circuit pattern on the substrate.

[0161] As described above, when forming an inorganic hard mask on a metal-containing film, silicon oxide films, silicon nitride films, and silicon oxynitride films (SiON films) can be formed by CVD or ALD methods. For example, a method for forming a silicon nitride film is described in Japanese Patent Application Publication No. 2002-334869 and International Publication No. 2004 / 066377. The thickness of the inorganic hard mask is preferably 5 to 200 nm, and more preferably 10 to 100 nm. Furthermore, as the inorganic hard mask, a SiON film, which has a high effect as an anti-reflective 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 temperatures of 300 to 500°C. The metal-containing film forming composition used in the present invention has high heat resistance and can withstand high temperatures of 300 to 500°C, so it is possible to combine an inorganic hard mask formed by CVD or ALD with a metal-containing film formed by rotary coating.

[0162] As described above, a photoresist film may be formed as a resist top layer on an inorganic hard mask, or an organic anti-reflective coating (BARC) or adhesion film may be formed on the inorganic hard mask by spin coating, and then a photoresist film may be formed on top of that. In particular, when a SiON film is used as the inorganic hard mask, the two layers of anti-reflective coatings, the SiON film and BARC, make it possible to suppress reflection even in immersion lithography with high NA values ​​exceeding 1.0. Another advantage of forming BARC is that it has the effect of reducing the trailing 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 metal-containing film forming composition, a resist underlayer film is formed on the substrate to be processed, and the resist underlayer filmA metal-containing film is formed on a substrate by applying the metal-containing film-forming composition of the present invention and then heat-treating it to form a metal-containing film, forming a resist upper layer film on the metal-containing film using a photoresist material, pattern-exposing the resist upper layer film, developing it with a developer to form a pattern on the resist upper layer film, using the resist upper layer film with the pattern formed on it as a mask to transfer the pattern to the metal-containing film by dry etching, using the metal-containing film with the transferred pattern as a mask to transfer the pattern to the resist lower layer film by dry etching, and further processing the substrate to be processed using the resist lower layer film with the pattern formed on it as a mask to form a pattern on the substrate, thereby forming a semiconductor device circuit pattern on the substrate.

[0164] As described above, a photoresist film may be formed as a resist top layer on the metal-containing film, or an organic adhesion film may be formed on the metal-containing film by spin coating, and then a photoresist film may be formed on top of that. 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, the resist underlayer film can be formed using a coating-type organic underlayer film material, or by CVD or ALD methods. Examples of coating-type organic underlayer film materials include those listed in Japanese Patent Publication Nos. 2012-001687, 2012-077295, 2004-264710, 2005-043471, 2005-250434, 2007-293294, and 2008-065303. Japanese Patent Publication No. 2004-205685, Japanese Patent Publication No. 2007-171895, Japanese Patent Publication No. 2009-014816, Japanese Patent Publication No. 2007-199653, Japanese Patent Publication No. 2008-274250, Japanese Patent Publication No. 2010-122656, Japanese Patent Publication No. 2012-214720, Japanese Patent Publication No. 2014-0 Examples of resins and compositions can be found in Japanese Patent Publication No. 29435, International Publication No. 2012 / 077640, International Publication No. 2010 / 147155, International Publication No. 2012 / 077640, International Publication No. 2010 / 147155, International Publication No. 2012 / 176767, Japanese Unexamined Patent Publication No. 2005-128509, Japanese Unexamined Patent Publication No. 2006-259249, Japanese Unexamined Patent Publication No. 2006-259482, Japanese Unexamined Patent Publication No. 2006-293298, Japanese Unexamined Patent Publication No. 2007-316282, Japanese Unexamined Patent Publication No. 2012-145897, Japanese Unexamined Patent Publication No. 2017-119671, Japanese Unexamined Patent Publication No. 2019-044022, etc.

[0166] In the above multilayer resist process, the resist upper layer can be either positive or negative, and the same photoresist composition as commonly used can be used. After spin-coating the photoresist composition, pre-baking is performed, preferably at 60-180°C for 10-300 seconds. Thereafter, exposure is performed according to a conventional method, followed by post-exposure baking (PEB) and development to obtain the resist pattern. The thickness of the resist upper layer is not particularly limited, but is preferably 30-500 nm, and especially preferably 50-400 nm.

[0167] Furthermore, examples of exposure light include high-energy rays with wavelengths of 300 nm or less, specifically excimer lasers with wavelengths of 248 nm, 193 nm, and 157 nm, soft X-rays, electron beams, and X-rays with wavelengths of 3 to 20 nm.

[0168] As a method for forming the pattern of the resist upper layer film described above, it is preferable to use photolithography with a wavelength of 5 nm to 300 nm, direct writing with an electron beam, nanoimprinting, or a combination thereof to form the pattern.

[0169] Furthermore, it is preferable that the development method in the pattern formation method be alkaline development or development with an organic solvent.

[0170] Next, etching is performed using the obtained resist pattern as a mask. In the three-layer resist process, etching of the silicon-containing resist interlayer and inorganic hard mask is performed using a fluorocarbon gas with the upper resist pattern as a mask. This forms the silicon-containing resist interlayer pattern and the inorganic hard mask pattern.

[0171] Next, the metal-containing film is etched using the obtained silicon-containing resist interlayer pattern or inorganic hard mask pattern as a mask. It is preferable to use an etching gas mainly composed of chlorine-based gas for etching the metal-containing film.

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

[0173] The metal-containing films obtained using the metal-containing film-forming composition of the present invention have excellent etching resistance when these workpieces are etched.

[0174] The workpiece (workpiece substrate) is not particularly limited and can be any substrate such as Si, α-Si, p-Si, SiO2, SiN, SiON, W, TiN, Al, or a substrate on which the workpiece layer has been deposited. Various low-k films and their stopper films can be used as the workpiece layer, typically with a thickness of 50 to 10,000 nm, and especially 100 to 5,000 nm. When depositing the workpiece layer, the substrate and the workpiece layer are made of different materials.

[0175] The pattern formation method using the metal-containing film-forming composition of the present invention preferably uses a workpiece substrate having a structure or step with a height of 30 nm or more. As described above, the metal-containing film-forming composition of the present invention has excellent embedding / planarization characteristics, so even if the workpiece substrate has a structure or step (unevenness) with a height of 30 nm or more, a flat cured film can be formed. The height of the structure or step on 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 a pattern of the above height, by forming the metal-containing film-forming composition of the present invention and performing embedding / planarization, it is possible to make the film thickness of the resist interlayer and resist upper layer that are subsequently formed uniform, which makes it easier to secure the depth of exposure margin (DOF) during photolithography and is highly preferable.

[0176] <Tone-reversal pattern formation method using a metal-containing film-forming composition> Furthermore, in the present invention, as a tone-reversal pattern formation method using such a metal-containing film-forming composition, a resist underlayer film is formed on a substrate to be processed; a resist interlayer film, or a combination of an inorganic hard mask interlayer film selected from silicon oxide film, silicon nitride film, and 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 interlayer film, or the combination of the inorganic hard mask interlayer film and the organic thin film using a photoresist material; the resist upper layer film is pattern-exposed and then developed with a developer to form a pattern on the resist upper layer film; the resist upper layer film on which the pattern has been formed is used as a mask to transfer the pattern to the resist interlayer film, or the organic thin film and the inorganic hard mask interlayer film by dry etching; and the resist interlayer film or inorganic hard mask interlayer film on which the pattern has been transferred is used as a mask to dry etch The present invention provides a tone inversion pattern formation method, characterized by the steps of: transferring a pattern to a resist underlayer film; coating the resist underlayer film on which the pattern is formed with a metal-containing film using the metal-containing film forming composition; filling the gaps between the resist underlayer film patterns with the metal-containing film; etching back the metal-containing film covering the resist underlayer film on which the pattern is formed using a chemical stripper or dry etching; exposing the upper surface of the resist underlayer film on which the pattern is formed; removing the resist interlayer or hard mask interlayer remaining on the upper surface of the resist underlayer film by dry etching; removing the resist underlayer film on which the pattern is formed with the exposed surface by dry etching; forming an inverted pattern of the original pattern on the metal-containing film; and processing 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.

[0177] An example of the formation of a tone-inverting pattern is shown below using Figure 2. As shown in Figure 2(G), a resist underlayer 7 made of a coated organic underlayer material is formed on a workpiece layer 2 stacked on a workpiece substrate 1, then a silicon-containing resist interlayer 4 is formed, and finally a resist upper layer 5 is formed on top of it.

[0178] Next, as shown in Figure 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 the resist upper layer film pattern 5a (Figure 2(I)). Using this obtained resist upper layer film pattern 5a as a mask, the silicon-containing resist interlayer film 4 is etched using a CF-based gas to form the silicon-containing resist interlayer film pattern 4a (Figure 2(J)). After removing the resist upper layer film pattern 5a, the obtained silicon-containing resist interlayer film pattern 4a is used as a mask to oxygen plasma etch the resist underlayer film 7 made of a coated organic underlayer film material to form the resist underlayer film pattern 7a made of a coated organic underlayer film material (Figure 2(K)).

[0179] After applying the metal-containing film-forming composition of the present invention onto a resist underlayer pattern 7a made of a coating-type organic underlayer material, a metal-containing film 8 is coated by heat treatment, filling the gaps between the resist underlayer patterns 7a made of the coating-type organic underlayer material with the metal-containing film (Figure 2(L)). Next, the metal-containing film 8 covering the resist underlayer pattern 7a made of the coating-type organic underlayer material is etched back using a chemical stripper or dry etching to expose the upper surface of the resist underlayer pattern 7a made of the coating-type organic underlayer material (Figure 2(M)). Furthermore, the silicon-containing resist interlayer pattern 4a remaining on the upper surface of the resist underlayer pattern 7a made of the coating-type organic underlayer material is removed by dry etching (Figure 2(N)). Next, the resist underlayer pattern 7a, which is made of a coated organic underlayer material, is removed by dry etching, and an inverted pattern of the original pattern is formed on the metal-containing film (forming a metal-containing film pattern 8a which is an inverted resist underlayer pattern) (Figure 2(O)). Then, the workpiece substrate is processed using the metal-containing film pattern 8a which is an inverted resist underlayer pattern as a mask to form a tone-inverted pattern on the workpiece substrate (Figure 2(P)).

[0180] As described above, when forming a resist underlayer film on a substrate to be processed, the resist underlayer film can be formed using a method with a coating-type organic underlayer film material, or by CVD or ALD methods. Examples of coating-type organic underlayer film materials include JP 2012-1687, JP 2012-77295, JP 2004-264710, JP 2005-043471, JP 2005-250434, JP 2007-293294, JP 2008-65303, and JP Japanese Patent Publication No. 2004-205685, Japanese Patent Publication No. 2007-171895, Japanese Patent Publication No. 2009-14816, Japanese Patent Publication No. 2007-199653, Japanese Patent Publication No. 2008-274250, Japanese Patent Publication No. 2010-122656, Japanese Patent Publication No. 2012-214720, Japanese Patent Publication No. 2014-29435, Examples of resins and compositions can be found in Japanese Patent Publication No. WO2012 / 077640, International Publication No. WO2010 / 147155, International Publication No. WO2012 / 077640, International Publication No. WO2010 / 147155, International Publication No. WO2012 / 176767, Japanese Patent Publication No. 2005-128509, Japanese Patent Publication No. 2006-259249, Japanese Patent Publication No. 2006-259482, Japanese Patent Publication No. 2006-293298, Japanese Patent Publication No. 2007-316282, Japanese Patent Publication No. 2012-145897, Japanese Patent Publication No. 2017-119671, Japanese Patent Publication No. 2019-44022, etc.

[0181] In the tone inversion pattern formation method described above, it is preferable to coat the obtained resist underlayer pattern with a metal-containing film formation composition, and then remove the metal-containing film using a dry etching gas mainly composed of chlorine gas to expose the upper surface of the resist underlayer pattern. Subsequently, the resist interlayer or hard mask interlayer remaining on the resist underlayer is removed by dry etching with a fluorocarbon gas, and the exposed resist underlayer pattern on the surface is removed by dry etching with an oxygen gas to form a metal-containing film pattern.

[0182] In the tone inversion pattern formation method described above, the resist underlayer film pattern preferably has structures or steps with a height of 30 nm or more. As described above, the metal-containing film-forming composition of the present invention has excellent embedding / planarization properties, so even if the film to be processed has structures or steps (unevenness) with a height of 30 nm or more, a flat cured film can be formed. The height of the structures or steps 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 a resist underlayer film pattern having a pattern of the above height, it is highly preferable to form the metal-containing film-forming composition of the present invention and perform embedding / planarization, as this enables high-precision pattern inversion / transfer. Compared to resist underlayer films using conventional coating-type organic underlayer film materials, it has excellent dry etching resistance using fluorocarbon gases, so by inverting the resist underlayer film pattern with the metal-containing film-forming composition, a desired resist pattern can be formed on the film to be processed with high precision. [Examples]

[0183] The present invention will be further described below with reference to synthesis examples, comparative synthesis examples, examples, and comparative examples, but the present invention is not limited thereto. The molecular weight and dispersion were determined by calculating the weight-average molecular weight (Mw) and number-average molecular weight (Mn) in polystyrene terms using gel permeation chromatography (GPC) with tetrahydrofuran as the eluent, and then determining the dispersion (Mw / Mn).

[0184] [Example of combination] The following synthesis examples and comparative examples used 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. Each raw material group is shown below. Note that, as mentioned above, isomers exist for compounds (TT2), (TT3), (TT5), and (P-3), but one representative structure is shown.

[0185] Tin compounds (Sn): [ka] (nBu represents a n-butyl group, tBu represents a tert-butyl group, and Oc represents a n-octyl group.)

[0186] Raw material group T: [ka]

[0187] Raw material group P: [ka]

[0188] [Synthesis Example 1] Synthesis of Metal-Containing Film-Forming Compound (M-1) (Reaction 1) 5.0 g of tin compound (Sn-1), 1.9 g of raw material (TT1), and 100 g of toluene were added and reacted at 130°C for 5 hours while removing water. (Reaction 2) The mixture was allowed to return to room temperature, an additional 2.5 g of (Sn-1) was added, and the reaction was continued at 130°C for another 5 hours while removing water. Toluene was removed under reduced pressure, and the mixture was suspended in methanol, filtered, and washed to obtain compound (M-1).

[0189] [Synthesis Examples 2-8] Synthesis of Metal-Containing Film-Forming Compounds (M-2)-(M-8) By changing the tin compound and raw material T as shown in Table 1 and performing the same procedure as in Synthesis Example 1, metal-containing film-forming compounds (M-2) to (M-8) were obtained. [Table 1]

[0190] [Synthesis Example 9] Synthesis of Metal-Containing Film-Forming Compound (M-9) (Reaction 1) 5.0 g of tin compound (Sn-1), 3.1 g of raw material (TT9), and 100 g of toluene were added and reacted at 130°C for 5 hours while removing water. (Reaction 2) The mixture was allowed to return to room temperature, and an additional 2.8g of (Sn-5) and 2.2g of (P-1) were added. The mixture was reacted at 130°C for 12 hours. Toluene was removed under reduced pressure, and the mixture was suspended in methanol, filtered, and washed to obtain compound (M-9).

[0191] [Synthesis Examples 10-16] Synthesis of Metal-Containing Film-Forming Compounds (M-10)-(M-16) By changing the tin compound and raw material T as shown in Table 2 and performing the same procedure as in Synthesis Example 9, metal-containing film-forming compounds (M-10) to (M-16) were obtained. [Table 2]

[0192] [ka] (In the above formula, Bn represents a benzyl group.)

[0193] [Synthesis of metal-containing film-forming compound (R-1) for comparative example] 5.0 g of tin compound (Sn-1), 8.6 g of raw material group P (P-2), and 100 g of toluene were added and reacted at 130°C for 7 hours while removing water. After the reaction, the solvent was removed under reduced pressure to obtain (R-1). [ka]

[0194] [Synthesis of metal-containing film-forming compound (R-2) for comparative example] 5.0 g of tin compound (Sn-1), 6.8 g of raw material group T (TT14), and 50 g of toluene were added and reacted at 130°C for 7 hours while removing water. After the reaction, the solvent was removed under reduced pressure to obtain (R-2). [ka]

[0195] [Weight-average molecular weight and degree of dispersion] The weight-average molecular weight (Mw) and dispersion (Mw / Mn) were determined for the above compounds (M-1) to (M-16), (R-1), and (R-2). The results are shown in Table 3. Note that the weight-average molecular weight (Mw) and number-average molecular weight (Mn) are polystyrene-converted values ​​obtained by the GPC method using tetrahydrofuran, and the dispersion was determined from these values. [Table 3]

[0196] [Synthesis of metal-containing film-forming compound (R-3) for comparative examples] As a metal-containing compound intended for use in photoresists, Patent No. 702894 0 We synthesized the tin compound reported in [Synthesis Example 8] of the publication. Isopropyltriphenyltin 3g and succinic acid 1.4g of Acetonitrile 20ml l The mixture was dissolved and refluxed for 24 hours. After the reaction, the solvent was removed under reduced pressure to obtain the tin-containing compound (R-3). [ka]

[0197] [Synthesis of metal-containing film-forming compound (R-4) for comparative examples] 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 mixture of 0.2 g of p-toluenesulfonic acid monohydrate and 3.0 g of PGME, which had been mixed and homogenized beforehand, was slowly added dropwise, and the reaction was carried out at an internal temperature of 120°C for 8 hours. After the reaction was complete, the mixture was returned to room temperature, and 150 g of ultrapure water was added while stirring. After standing for 1 hour, the upper layer was fractionated. This was then dissolved in 30 g of PGME, and the same procedure was repeated twice. Then, 300 ml of MIBK (methyl isobutyl ketone) was added, and the mixture was washed four times with 200 ml of pure water, and the organic layer was dried under reduced pressure. Then, 20 g of tin raw material (Sn-1) and 300 g of toluene were added, and the mixture was stirred at 130°C for 8 hours. After the reaction, the solvent was removed under reduced pressure to obtain (R-4). [ka]

[0198] [Synthesis of metal-containing film-forming compound (R-5) for comparative examples] As a compound having a different metal from the metal-containing film-forming compound of the present invention, we synthesized a titanium compound reported in [Synthesis Example A-II] of Japanese Patent Publication No. 6189758. 284 g of titanium tetraisopropoxide (manufactured by Tokyo Chemical Industry Co., Ltd.) was added dropwise to a 500 g solution of IPA (isopropyl alcohol) while stirring. A 500 g solution of IPA containing 27 g of deionized water was added dropwise at room temperature over 2 hours. 120 g of 2-methyl-2,4-pentanediol was added to the resulting solution and stirred at room temperature for 30 minutes. This solution was concentrated under reduced pressure at 30°C, then heated to 60°C, and continued under reduced pressure until no more distillate was observed. Once no distillate was observed, 1,200 g of PGMEA was added and heated at 40°C under reduced pressure until no more IPA distilled, yielding 1,000 g of a PGMEA solution of titanium-containing compound (R-5) (compound concentration 20% by mass).

[0199] [Synthesis of organic film-forming resin (R-6) for comparative examples] 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 pre-mixed and homogenized, was slowly added dropwise, and the reaction was carried out at an internal temperature of 80°C for 8 hours. After the reaction was complete, the mixture was cooled to room temperature, 2,000 ml of MIBK was added, and the mixture was washed six times with 500 ml of pure water. The organic layer was dried under reduced pressure. 300 g of THF was added to the residue to make a homogenized solution, and then 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). The weight-average molecular weight (Mw) and dispersion (Mw / Mn) were determined using GPC, and the following results were obtained. (R-6): Mw=3,300, Mw / Mn=2.54 [ka]

[0200] "Evaluation of solvent solubility and heat resistance" The solvent solubility and heat resistance of metal-containing compounds were evaluated. Compounds (M-1) to (M-16) synthesized in Synthesis Examples 1 to 16, as well as comparative examples (R-1) to (R-5), were prepared as 15.0 wt% solutions of propylene glycol monomethyl ether acetate (PGMEA) and cyclohexanone (CyHO), respectively. After stirring for 24 hours, compounds that were completely dissolved were marked with ○, those that were partially undissolved with △, and those that were completely suspended with ×. Each compound was weighed out at 3.0 mg and heated in air from 30°C to 300°C at a rate of 10°C / min using a RIGAKU Thermo plus EVO2. At this time, compounds with a weight loss of 40% or less upon heating to 300°C were marked with A, those with a weight loss of 40-60% were marked with B, and those with a weight loss of 60% or more were marked with C. These results are shown in Table 4.

[0201] [Table 4]

[0202] As shown in Table 4, the metal-containing film-forming compounds (M-1) to (M-16) of the present invention can be prepared in solution with cyclohexanone, and their solubility was confirmed to be sufficient. Furthermore, the metal-containing film-forming compounds (M-9) to (M-16) with disrupted symmetry can also be prepared in solution with PGMEA, and their excellent solvent solubility was confirmed. Similarly, comparative compounds, which are a group of compounds that partially omit elements of the present invention, showed similar solubility, however, (R-4), which has a structure in which tin is introduced into all repeating units of the polymer, had no solubility at all. In addition, in TG-DTA measurements, all of the compounds of the present invention... 300The weight loss when heated to °C was 40% or less, but in the comparative compounds, (R-2) decreased by 49%, (R-3) by 68%, and (R-5) by 56%. Compared to these, the compounds of the present invention were found to have superior heat resistance.

[0203] [Metal-containing film forming composition UDL-1] A metal-containing film-forming compound (M-1) was dissolved in cyclohexanone (CyHO) solvent containing 0.5% by mass of surfactant FC-4430 (manufactured by Sumitomo 3M Co., Ltd.) in the proportions shown in Table 5, and the mixture was filtered through a 0.2 μm membrane filter to prepare a metal-containing film-forming composition (UDL-1).

[0204] [Preparation of metal-containing film-forming compositions (UDL-2 to 23) and comparative metal-containing film-forming compositions (comparative examples UDL-1 to 5)] Each chemical solution was prepared in the same manner as UDL-1, except that the type and content of each component were as shown in Table 5. In Table 5, "-" indicates that the corresponding component was not used. The following formula (C-1) was used as the crosslinking agent, 1,6-diacetoxyhexane (boiling point 260°C) was used as the high-boiling point solvent (B2-1), a polymer for fluidity enhancer (E-1) was used, and the following formula (F-1) was used as the thermoacid generator (TAG).

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

[0206] [Example of polymer synthesis for fluidity enhancers] Synthesis of polymer (E-1) Under a nitrogen atmosphere, 20.0 g of cresol novolac, 27.6 g of potassium carbonate, and 100 g of DMF were added and a homogeneous dispersion was prepared 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 the separated aqueous layer was removed. The organic layer was then washed six times with 100 g of 3% nitric acid aqueous solution and 100 g of pure water, and the organic layer was dried under reduced pressure to obtain resin (E-1). The weight-average molecular weight (Mw) and dispersion (Mw / Mn) were determined using GPC, and the following results were obtained. (E-1): Mw=8,500, Mw / Mn=3.46 [ka]

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

[0208] [Table 5]

[0209] [Film-forming test] The metal-containing film-forming compositions prepared above (UDL-1 to 23, Comparative Examples UDL-1 to 4) were applied to a silicon substrate, baked at 180°C for 60 seconds, and then baked again at 250°C for another 60 seconds. The film thickness (a [nm]) was then measured. Furthermore, the film thickness from the center to the outer edge of the substrate was measured, and the difference between the maximum and minimum film thicknesses, Range (b [nm]), was calculated to determine the in-plane uniformity ((b / a) × 100). Furthermore, PGMEA solvent was dispensed onto the sample, left for 30 seconds to spin-dry, and then baked at 100°C for 60 seconds to evaporate the PGMEA (Rework). The film thickness (c [nm]) was then measured. The difference in film thickness before and after PGMEA treatment (residual film percentage: (c / a) × 100) was calculated. The results are shown in Table 6 below.

[0210] [Table 6]

[0211] As shown in Table 6, the metal-containing film-forming compositions of the present invention (Examples 1-1 to 1-23) were confirmed to have excellent film-forming properties, with in-plane uniformity of 5.0% or less after high-temperature additional baking at 250°C, enabling the formation of flat films with minimal irregularities. On the other hand, Comparative Examples 1-1 to 1-2, which used comparative compound R-1 (which lacked T units and contained only one tin atom in a single molecule) and comparative compound R-2 (which consisted only of T units), also showed relatively good in-plane uniformity, but were inferior to the examples using the compounds of the present invention. This is thought to be because the lack of radical-active units in the Sn-alkyl bond prevented efficient crosslinking by radicals, resulting in film irregularities due to sublimation and decomposition products. Furthermore, Comparative Example 1-3, which used comparative compound R-3 (which contained multiple tin atoms in a single molecule but lacked diol units and consisted only of esters), resulted in significant film irregularities due to insufficient molecular weight and the influence of sublimation products. In Comparative Examples 1-4, which used Comparative Example UDL-4 containing the titanium compound (R-5) reported in [Synthesis Example A-II] of Japanese Patent Publication No. 6189758, a film with many irregularities and an in-plane uniformity exceeding 5.0% after baking was formed, indicating poor film formation. This is presumed to be because the titanium compound has poor heat resistance, produces many sublimated products, and exhibits significant volume shrinkage. Furthermore, Examples 1-17 to 1-20, which used UDL-17 to 20 with the addition of the crosslinking agent (C-1), showed improved in-plane uniformity compared to Examples 1-5, 6, 8, and 10, which used UDL-5, 6, 8, and 10 without the addition. This is thought to be because the crosslinking agent allowed the crosslinking reaction to proceed more efficiently, suppressing the generation of sublimations and decomposition products. In addition, Example 1-22, which used UDL-22 with the addition of the acid generator (F-1), showed a higher residual film rate after rework compared to Example 1-14 without the addition, suggesting that the crosslinking reaction progressed more rapidly. Moreover, when comparing examples with and without the addition of other fluidity enhancers and high-boiling point solvents, it was confirmed that there were no significant differences in in-plane uniformity or residual film rate after rework.

[0212] [Embedding characteristics evaluation] The above metal-containing film-forming compositions (UDL-1 to 23) and comparative examples UDL-3 and 4 were each applied to an SiO2 wafer substrate having a dense line and space pattern (line width 40 nm, line depth 120 nm, distance between the centers of two adjacent lines 80 nm), and heated at 250°C for 60 seconds using a hot plate to form a metal-containing film with a thickness of 100 nm. The substrate used was a base substrate 9 (SiO2 wafer substrate) having a dense line and space pattern as shown in Figure 3(Q) (overhead 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 whether it could be embedded in a stepped substrate. The results are shown in Table 7. When a metal-containing film-forming composition with poor embedding characteristics was used, it was not possible to successfully embed the stepped substrate in this evaluation. When a metal-containing film-forming composition with good embedding properties is used, the spaces between lines of the substrate 9 having a dense line and space pattern can be filled without gaps, as shown in Figure 3(S) in this evaluation. ○ indicates that embedding is possible without large voids, △ indicates that embedding is possible but large voids occur, and × indicates that embedding is not possible.

[0213] [Table 7]

[0214] As shown in Table 7, Examples 2-1 to 2-23, using the resist metal-containing film-forming composition of the present invention, were able to fill dense line and space patterns without generating voids when baked at 250°C, confirming that they have good filling characteristics. On the other hand, Comparative Example 2-1, which used Comparative Example UDL-3, which had poor film-forming properties, could not be filled, and in Comparative Example 2-2, which used Comparative Example UDL-4, which contained a 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 presumed to be because, as observed in the heat resistance evaluation and film-forming property evaluation above, the compound of the present invention produces little sublimation and has small volume shrinkage due to high-temperature baking, making it possible to fill steps without generating voids, while Comparative Examples UDL-3 and UDL-4, which have poor heat resistance, produce a lot of sublimation and have large volume shrinkage, resulting in the generation of voids or inability to fill.

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

[0216] The CF4 gas etching conditions are as follows. Chamber pressure 200mT RF Power 300W CF4 gas flow rate: 100 sccm Time 20sec

[0217] The O2-based gas etching conditions are as follows. Chamber pressure 500mT RF Power 100W O2 gas flow rate: 30 sccm N2 gas flow rate 270s c cm Time 20sec

[0218] [Table 8]

[0219] As shown in Table 8, in Examples 3-1 to 3-9, which used the resist metal-containing film-forming composition of the present invention, the tin content 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, which used Comparative UDL-1 and 2, which contained only one tin atom in each molecule, the tin content was slightly less than 55 wt%, confirming that it was inferior in tin content. Furthermore, in Examples 3-1 to 3-5, which used UDL-1, 2, 5, 7, and 13 without additives, the tin content was 80 wt% or more, indicating that the film after firing had a high tin content. This confirmed that including multiple tin atoms in each molecule results in a film with a high tin content, and it was shown that secondary electron emission due to EUV light absorption can be expected. Furthermore, in the etching resistance evaluation, materials with a higher tin content showed better etching resistance to both CF-based and O2-based gases. In particular, the etching resistance to O2 etching was significantly improved compared to Comparative Example 3-3, which was an organic underlayer film without tin.

[0220] From the above, the metal oxide film-forming compound of the present invention is an organotin compound that achieves a high balance between heat resistance and a high tin content. Therefore, a metal-containing film-forming composition using this compound has superior dry etching resistance compared to conventional organic underlayer film materials, and can provide a resist underlayer film material that combines film-forming properties and embedding properties. It is extremely useful as a resist underlayer film material used in multilayer resist methods and as an inversion agent used in tone inversion etching methods.

[0221] This specification includes the following embodiments: [1]: A metal-containing film-forming compound, characterized in that the compound is represented by the following general formula (M). [ka] (In the above general formula (M), T is independently of the following general formula (T-1) or (T-2), P is independently of *OCOR (* represents a bond with a Sn atom, and R represents a monovalent organic group), and Q is independently of a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 aliphatic unsaturated hydrocarbon group containing one or more double or triple bonds, or a substituted or unsubstituted carbon The elements are aryl groups with 6 to 30 carbon atoms, substituted or unsubstituted arylalkyl groups with 7 to 31 carbon atoms, halogen atoms, and alkoxy groups with 1 to 20 carbon atoms. Furthermore, n1, n2, and n3 are integers satisfying n1≧1, n2≧0, and n3≧1, and n1+n2+n3=4. When n1≧2, T may be the same or different; when n2=2, P may be the same or different; and when n3≧2, Q may be the same or different. [ka] (In the above general formulas (T-1) and (T-2), R1 is a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 aliphatic unsaturated hydrocarbon group containing one or more double or triple bonds, a substituted or unsubstituted C6-C30 aryl group, or a substituted or unsubstituted C7-C31 arylalkyl group, and * is the bond with the Sn atom in the above general formula (M). W1 is a substituted or unsubstituted C1-C40 linear, branched or cyclic saturated or unsaturated hydrocarbon group (including aromatic ring 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, or may form a heterocyclic structure via the heteroatom. R2 is a substituted or unsubstituted C1-C20 alkyl group, or a substituted or unsubstituted s1 represents a 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 or triple bonds, a hydroxyl group, an amino group, or a halogen atom, where s1 is an integer from 0 to 1 and m is an integer from 0 to 1. W2 is a substituted or unsubstituted linear, branched, or cyclic saturated or unsaturated hydrocarbon group (including aromatic ring groups) having 1 to 40 carbon atoms, and the hydrocarbon group may contain 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, or a heterocyclic structure via the heteroatom. s2 is an integer from 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 having 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, it forms a carbonyl group, and W2 and R3 may bond to each other to form a ring structure. [2]: The metal-containing film-forming compound of [1], characterized in that in the general formula (T-1), W1 is a linear, branched, or cyclic saturated or unsaturated hydrocarbon group (including aromatic ring groups) having 1 to 10 carbon atoms, which may contain a hydroxyl group or an amino 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, or an ester group) or a group represented by the following general formulas (W1-1) to (W1-4). [ka] (In the above general formulas (W1-1) to (W1-4), R W (#1 represents the bond with the ester group, and #2 represents the bond with the benzene ring.) [3]: A metal-containing film-forming compound according to [1] or [2], characterized in that W2 in the general formula (T-2) is a linear, branched, or cyclic saturated or unsaturated hydrocarbon group (including an aromatic ring group) having 1 to 10 carbon atoms, which may contain a hydroxyl group or an amino group, or a cyclic hydrocarbon group bonded to R3 (the hydrocarbon group contains an oxygen atom, a nitrogen atom, or a sulfur atom, and may form an ether bond, a carbonyl group, or an ester group), or a group represented by the following general formulas (W2-1) to (W2-4). [ka] (In the above general formulas (W2-1) to (W2-4), R W (#1 and #2 represent the ester group and the bond to the carbon atom, respectively, as they are divalent organic groups with 1 to 23 carbon atoms.) [4]: R in the above general formulas (W1-1) to (W1-4) W A metal-containing film-forming compound characterized in that the group is an unsaturated hydrocarbon group having 2 to 23 carbon atoms [2]. [5]: The above R W A metal-containing film-forming compound of [4] characterized in that the group is represented by the following general formula (1). [ka] (In the above general formula (1), R a, R b and R c R is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. a and R b These may be bonded, forming a cyclic substituent. (*1 and *2 represent the bond with the carbonyl group, and *1 and *2 may be reversed.) [6]: R in the above general formulas (W2-1) to (W2-4) W A metal-containing film-forming compound characterized in that the group is an unsaturated hydrocarbon group having 2 to 23 carbon atoms [3]. [7]: The above R W A metal-containing film-forming compound of [6] characterized in that the group is represented by the following general formula (1). [ka] (In the above general formula (1), R a , R b and R c R is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. a and R b These may be bonded, forming a cyclic substituent. (*1 and *2 represent the bond with the carbonyl group, and *1 and *2 may be reversed.) [8]: A metal-containing film-forming compound from any one of [1] to [7], characterized in that, in the general formula (M), n2 is 1, and R of *OCOR of P is 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). [ka] (In the above general formulas (A-1) to (A-4), Y A1 , Y A2 Each of these may be the same or different from the others, and is a substituted or unsubstituted saturated or unsaturated divalent organic group having 1 to 23 carbon atoms, 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. AR is a hydrogen atom, a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms in a saturated state or 2 to 20 carbon atoms in an unsaturated state, 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. A1 This is an organic group represented by the following general formula (2) in which a protecting group is removed by the action of either an acid, heat, or both, generating one or more hydroxyl groups or carboxyl groups, and * represents the bond with the carbonyl group. [ka] (In the above general formula (2), R A2 * is an organic group whose protecting group is removed by the action of acid, heat, or both, and * is Y A1 Or Y A2 (This represents the connection point.) [ka] (In the above 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 bond with the carbonyl group.) [ka] (In the above general formula (B), Y B R is a substituted or unsubstituted saturated or unsaturated divalent organic group having 1 to 20 carbon atoms, 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. B (This is either a hydroxyl group or one of the structures shown in the following general formulas (B-1) to (B-3).) [ka] (In the above general formulas (B-1) to (B-3), R B1 is a hydrogen atom or a monovalent organic group with 1 to 10 carbon atoms, q represents 0 or 1, and * represents Y B (This represents the connection point.) [ka] (In the above general formula (4), X is a divalent organic group having 1 to 31 carbon atoms, C is one of the groups represented by the following general formulas (C-1) to (C-4), and * represents the bond with the carbonyl group.) [ka] (In the above general formulas (C-1) and (C-3), R C1 R is a hydrogen atom or a methyl group, and they may be the same or different from each other in the same formula. In (C-3) and (C-4), R C2 This refers to 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. * indicates a bond with a carbonyl group. [9]: Y in the above general formulas (A-1) to (A-4) A1 A metal-containing film-forming compound according to [8], characterized in that X in the general formula (3) or X in the general formula (4) is an unsaturated hydrocarbon group having 2 to 23 carbon atoms.

[10] : Y in the above general formulas (A-1) to (A-4) A1 A metal-containing film-forming compound of the type [9], characterized in that X in the general formula (3) or X in the general formula (4) is a group represented by the following general formula (1). [ka] (In the above general formula (1), R a , R b and R c R is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. a and R b These may be bonded, forming a cyclic substituent. (*1 and *2 represent the bond with the carbonyl group, and *1 and *2 may be reversed.)

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

[10] .

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

[11] , characterized in that the composition is a metal-containing film-forming composition 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 enhancer, and (f) an acid generator.

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

[11] or

[12] , 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, (I-1) A step of forming a metal-containing film by applying one of the metal-containing film-forming compositions from

[11] to

[13] onto a substrate to be processed, and then heat-treating it. (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, develop it 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 workpiece substrate using the metal-containing film on which the pattern is formed as a mask to form a pattern on the workpiece substrate. A pattern forming method characterized by having the following features.

[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 one of the metal-containing film-forming compositions from

[11] to

[13] onto a substrate to be processed, and then heat-treating it. (II-2) A step of forming a resist interlayer on the metal-containing film, (II-3) A step of forming a resist upper layer film on the resist interlayer film using a photoresist material, (II-4) After pattern exposure of the resist upper layer film, develop it with a developer to form a pattern on the resist upper layer film. (II-5) A step of transferring the pattern to the resist interlayer by dry etching, using the resist upper layer on which the pattern is formed as a mask. (II-6) A step of transferring the pattern to the metal-containing film by dry etching using the resist interlayer on which the pattern has been transferred as a mask, and (II-7) A step of processing the workpiece substrate using the metal-containing film on which the pattern is formed as a mask to form a pattern on the workpiece substrate. A pattern forming method characterized by having the following features.

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

[11] to

[13] onto a substrate to be processed, and then heat-treating it. (III-2) The above Contains metal A step of forming an inorganic hard mask interlayer selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film on a film, (III-3) A step of forming an organic thin film on the inorganic hard mask interlayer, (III-4) A step of forming a resist upper layer film on the organic thin film using a photoresist material, (III-5) After pattern exposure of the resist upper layer film, develop it with a developer to form a pattern on the resist upper layer film. (III-6) A step of transferring the pattern to the organic thin film and the inorganic hard mask interlayer 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 the pattern to the metal-containing film by dry etching using the inorganic hard mask interlayer on which the pattern has been transferred as a mask, and (III-8) A step of processing the workpiece substrate using the metal-containing film on which the pattern is formed as a mask to form a pattern on the workpiece substrate. A pattern forming method characterized by having the following features.

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

[11] to

[13] on top, followed by 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 on the metal-containing film by spin coating, and then forming a resist upper layer film thereon using a photoresist material. (IV-4) After pattern exposure of the resist upper layer film, develop it with a developer to form a pattern on the resist upper layer film. (IV-5) Using the resist upper layer film on which the pattern is formed as a mask, a step of transferring the pattern to the metal-containing film, or the organic adhesion film and the metal-containing film, by dry etching. (IV-6) A step of transferring the pattern to the resist underlayer film by dry etching using the metal-containing film on which the pattern has been transferred as a mask, and (IV-7) A step of processing the substrate to be processed using the resist underlayer film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. A pattern forming method characterized by having the following features.

[18] A method for forming a pattern on a substrate to be processed, (V-1) A step of forming a resist underlayer film on the substrate to be processed. (V-2) A step of forming a resist interlayer, or a combination of an inorganic hard mask interlayer selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film, and an organic thin film on the resist underlayer film. (V-3) A step of forming a resist upper layer film using a photoresist material on the resist interlayer film, or a combination of an inorganic hard mask interlayer film and an organic thin film. (V-4) After pattern exposure of the resist upper layer film, develop it with a developer to form a pattern on the resist upper layer film. (V-5) A step of transferring the pattern to the resist interlayer, or the organic thin film and the inorganic hard mask interlayer, by dry etching, using the resist upper layer film on which the pattern is formed as a mask. (V-6) A step of transferring the pattern to the resist underlayer film by dry etching, using the resist interlayer film on which the pattern has been transferred, or an inorganic hard mask interlayer film, as a mask. (V-7) A step of coating the resist underlayer film on which the pattern is formed with one of the metal-containing film-forming compositions from

[11] to

[13] , then heat-treating it to coat it with a metal-containing film, thereby filling the gaps between the resist underlayer film patterns with the metal-containing film. (V-8) A step of etching back the metal-containing film covering the resist underlayer film on which the pattern has been formed by chemical stripping or dry etching, thereby exposing the upper surface of the resist underlayer film on which the pattern has been formed. (V-9) A step of removing the resist interlayer or hard mask interlayer remaining on the upper surface of the resist underlayer by dry etching. (V-10) A step of removing the resist underlayer film on which the exposed surface pattern is formed by dry etching, and forming an inverted pattern of the original pattern on the metal-containing film. (V-11) A process of processing the workpiece substrate using the metal-containing film on which the inverted pattern is formed as a mask to form the inverted pattern on the workpiece substrate. A pattern forming method characterized by having the following features.

[19] : The pattern formation method of

[16] or

[18] , characterized in that the inorganic hard mask interlayer is formed by CVD or ALD.

[0222] It should be noted that the present invention is not limited to the embodiments described above. The embodiments described above are illustrative, and any configuration that is substantially identical to the technical idea described in the claims of the present invention and achieves similar effects is included within the technical scope of the present invention. [Explanation of symbols]

[0223] 1...Substrate to be processed, 2...Layer to be processed, 2a...Pattern (Pattern formed on the layer to be processed) 3...Metal-containing resist underlayer film, 3a...Metal-containing resist underlayer film pattern, 4...Silicon-containing resist interlayer, 4a...Silicon-containing resist interlayer pattern, 5...Resist upper layer film, 5a...Resist upper layer film pattern, 6...Exposed area, 7...Resist underlayer film made of a coating-type organic underlayer film material, 7a...Resist underlayer film pattern made of a coating-type organic underlayer film material, 8... Metal-containing film, 8a... Metal-containing film pattern obtained by inverting the resist underlayer film pattern, 9…Underlayment substrate with densely packed lines and spaces, 10…Underlayment film containing metal resist.

Claims

1. A metal-containing film-forming compound, characterized in that the compound is represented by the following general formula (M). 【Chemistry 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.) 【Chemistry 2】 (In the general formulas (T-1) and (T-2), R １ is a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 aliphatic unsaturated hydrocarbon group containing one or more double or triple bonds, a substituted or unsubstituted C6-C30 aryl group, or a substituted or unsubstituted C7-C31 arylalkyl group, where * is the bond with the Sn atom in the general formula (M). W １ R is a substituted or unsubstituted linear, branched, or cyclic saturated or unsaturated hydrocarbon group (including aromatic ring groups) having 1 to 40 carbon atoms, wherein 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, or may form a heterocyclic structure via the heteroatom. ２ represents a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 aliphatic unsaturated hydrocarbon group containing one or more double or triple bonds, a hydroxyl group, an amino group, or a halogen atom. １ w is an integer between 0 and 1, and m is an integer between 0 and 1. ２ is a substituted or unsubstituted linear, branched, or cyclic saturated or unsaturated hydrocarbon group (including aromatic ring groups) having 1 to 40 carbon atoms, wherein 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, or a heterocyclic structure via the heteroatom. ２ s is an integer between 0 and 1. ３ is 1 or 2, s ３ When R is 1 ３ is a hydrocarbon group having a hydrogen atom or a hydroxyl group having 1 to 10 carbon atoms, s ３ When R is 2 ３ It is an oxygen atom and together with the carbon atom it is bonded to, it forms a carbonyl group, W ２ and R ３ They may be bonded to each other, forming a ring structure.

2. In the general formula (T-1), W １ A linear, branched, or cyclic saturated or unsaturated hydrocarbon group having 1 to 10 carbon atoms (including aromatic ring groups) which may contain a hydroxyl group or an amino 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, or an ester group) or the following general formula (W １ -1) ~ (W １ The metal-containing film-forming compound according to claim 1, characterized in that it is one of the groups represented by -4). 【Transformation 3】 (The general formula (W) １ -1) ~ (W １ -4) Medium, R Ｗ It is a divalent organic group having 1 to 23 carbon atoms, # １ The bond with the ester group, # ２ (This represents the bond with the benzene ring.)

3. In the general formula (T-2), W ２ R is a linear, branched, or cyclic saturated or unsaturated hydrocarbon group (including aromatic ring groups) having 1 to 10 carbon atoms, which may contain a hydroxyl group or an amino group, or ３ A cyclic hydrocarbon group bonded to each other (the hydrocarbon group contains an oxygen atom, a nitrogen atom, or a sulfur atom, and may form an ether bond, a carbonyl group, or an ester group), or the following general formula (W ２ -1) ~ (W ２ The metal-containing film-forming compound according to claim 1, characterized in that it is one of the groups represented by -4). 【Chemistry 4】 (The general formula (W) ２ -1) ~ (W ２ -4) Medium, R Ｗ It is a divalent organic group having 1 to 23 carbon atoms, # １ , # ２ (These represent the ester group and the bond with the carbon atom, respectively.)

4. The general formula (W １ -1) ~ (W １ -4) R Ｗ The metal-containing film-forming compound according to claim 2, characterized in that the group is an unsaturated hydrocarbon group having 2 to 23 carbon atoms.

5. The aforementioned R Ｗ The metal-containing film-forming compound according to claim 4, characterized in that the group is represented by the following general formula (1). 【Transformation 5】 (In the above general formula (1), R ａ , R ｂ and R ｃ R is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. ａ and R ｂ These may be bonded, forming a cyclic substituent. (*1 and *2 represent the bond with the carbonyl group, and *1 and *2 may be reversed.)

6. The general formula (W ２ -1) ~ (W ２ -4) R Ｗ The metal-containing film-forming compound according to claim 3, characterized in that the group is an unsaturated hydrocarbon group having 2 to 23 carbon atoms.

7. The aforementioned R Ｗ The metal-containing film-forming compound according to claim 6, characterized in that the group is represented by the following general formula (1). 【Transformation 6】 (In the above general formula (1), R ａ , R ｂ and R ｃ R is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. ａ and R ｂ These may be bonded, forming a cyclic substituent. (*1 and *2 represent the bond with the carbonyl group, and *1 and *2 may be reversed.)

8. In the general formula (M), n ２ The metal-containing film-forming compound according to claim 1, characterized in that is 1 and R of *OCOR of P is 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). 【Transformation 7】 (In the above general formulas (A-1) to (A-4), Y Ａ１ , Y Ａ２ Each of these may be the same or different from the others, and is a substituted or unsubstituted saturated or unsaturated divalent organic group having 1 to 23 carbon atoms, 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. Ａ R is a hydrogen atom, a substituted or unsubstituted monovalent organic group having 1 to 20 saturated carbon atoms or 2 to 20 unsaturated 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. Ａ１ This is an organic group represented by the following general formula (2) in which a protecting group is removed by the action of either an acid, heat, or both, generating one or more hydroxyl groups or carboxyl groups, and * represents the bond with the carbonyl group. 【Transformation 8】 (In the above general formula (2), R Ａ２ * is an organic group whose protecting group is removed by the action of acid, heat, or both, and * is Y Ａ１ Or Y Ａ２ (This represents the connection point.) 【Chemistry 9】 (In the above 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 bond with the carbonyl group.) 【Chemistry 10】 (In the above general formula (B), Y Ｂ R is a substituted or unsubstituted saturated or unsaturated divalent organic group having 1 to 20 carbon atoms, 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. Ｂ (This is either a hydroxyl group or one of the structures shown in the following general formulas (B-1) to (B-3).) 【Chemistry 11】 (In the above general formulas (B-1) to (B-3), R Ｂ１ is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, q represents 0 or 1, and * represents Y Ｂ (This represents the connection point.) 【Chemistry 12】 (In the above general formula (4), X is a divalent organic group having 1 to 31 carbon atoms, C is one of the groups represented by the following general formulas (C-1) to (C-4), and * represents the bond with the carbonyl group.) 【Chemistry 13】 (In the general formulas (C-1) and (C-3), R Ｃ１ R is a hydrogen atom or a methyl group, and they may be the same or different from each other in the same formula. In (C-3) and (C-4), R Ｃ２ This refers to 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. (* indicates a bond with a carbonyl group.)

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

10. In the above general formulas (A-1) to (A-4), Y Ａ１ The metal-containing film-forming compound according to claim 9, characterized in that X in the general formula (3) or X in the general formula (4) is a group represented by the following general formula (1). 【Chemistry 14】 (In the above general formula (1), R ａ , R ｂ and R ｃ R is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. ａ and R ｂ These may be bonded, forming a cyclic substituent. (*1 and *2 represent the bond with the carbonyl group, and *1 and *2 may be reversed.)

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

12. The metal-containing film-forming composition according to claim 11, characterized in that the composition is a metal-containing film-forming composition 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 enhancer, and (f) an acid generator.

13. The metal-containing film-forming composition 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, (I-1) A step of forming a metal-containing film by applying the metal-containing film-forming composition described in claim 11 onto a substrate to be processed, and then heat-treating it. (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 followed by development with a developer solution. (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 workpiece substrate using the metal-containing film on which the pattern is formed as a mask to form a pattern on the workpiece substrate. A pattern forming method characterized by having the following features.

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 the metal-containing film-forming composition described in claim 11 onto a substrate to be processed, and then heat-treating it. (II-2) A step of forming a resist interlayer on the metal-containing film, (II-3) A step of forming a resist upper layer film on the resist interlayer film using a photoresist material, (II-4) After pattern exposure of the resist upper layer film, develop it with a developer to form a pattern on the resist upper layer film. (II-5) A step of transferring the pattern to the resist interlayer by dry etching, using the resist upper layer on which the pattern is formed as a mask. (II-6) A step of transferring the pattern to the metal-containing film by dry etching using the resist interlayer on which the pattern has been transferred as a mask, and (II-7) A step of processing the substrate to be processed using the metal-containing film on which the pattern is formed as a mask to form a pattern on the substrate to be processed. A pattern forming method characterized by having the following features.

16. A method for forming a pattern on a substrate to be processed, (III-1) A step of forming a metal-containing film by applying the metal-containing film-forming composition described in claim 11 onto a substrate to be processed, and then heat-treating it. (III-2) A step of forming an inorganic hard mask interlayer selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film on the metal-containing film. (III-3) A step of forming an organic thin film on the inorganic hard mask interlayer, (III-4) A step of forming a resist upper layer film on the organic thin film using a photoresist material, (III-5) A step of forming a pattern on the resist upper layer film by pattern exposure followed by development with a developer solution. (III-6) A step of transferring the pattern to the organic thin film and the inorganic hard mask interlayer 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 the pattern to the metal-containing film by dry etching using the inorganic hard mask interlayer on which the pattern has been transferred as a mask, and (III-8) A step of processing the substrate to be processed using the metal-containing film on which the pattern is formed as a mask to form a pattern on the substrate to be processed. A pattern forming method characterized by having the following features.

17. A method for forming a pattern on a substrate to be processed, (IV-1) A step of forming a resist underlayer film on a substrate to be processed. (IV-2) A step of forming a metal-containing film by applying the metal-containing film-forming composition according to claim 11 onto the resist underlayer film and then heat-treating it, (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 on the metal-containing film by spin coating, and then forming a resist upper layer film thereon using a photoresist material. (IV-4) A step of forming a pattern on the resist upper layer film by pattern exposure followed by development with a developer solution. (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 on which the pattern is formed as a mask. (IV-6) A step of transferring the pattern to the resist underlayer film by dry etching using the metal-containing film on which the pattern has been transferred as a mask, and (IV-7) A step of processing the substrate to be processed using the resist underlayer film on which the pattern is formed as a mask to form a pattern on the substrate to be processed. A pattern forming method characterized by having the following features.

18. A method for forming a pattern on a substrate to be processed, (V-1) A step of forming a resist underlayer film on the substrate to be processed. (V-2) A step of forming a resist interlayer, or a combination of an inorganic hard mask interlayer selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film, and an organic thin film on the resist underlayer film. (V-3) A step of forming a resist upper layer film using a photoresist material on the resist interlayer film, or a combination of an inorganic hard mask interlayer film and an organic thin film. (V-4) A step of pattern exposure of the resist upper layer film, followed by development with a developer to form a pattern on the resist upper layer film. (V-5) A step of transferring the pattern to the resist interlayer, or the organic thin film and the inorganic hard mask interlayer, by dry etching, using the resist upper layer film on which the pattern is formed as a mask. (V-6) A step of transferring the pattern to the resist underlayer film by dry etching, using the resist interlayer film on which the pattern has been transferred, or an inorganic hard mask interlayer film, as a mask. (V-7) A step of coating the resist underlayer film on which the pattern is formed with the metal-containing film composition according to claim 11, and then heat-treating it to coat it with a metal-containing film, thereby filling the gaps between the resist underlayer film patterns with the metal-containing film. (V-8) A step of etching back the metal-containing film covering the resist underlayer film on which the pattern has been formed by chemical stripping or dry etching, thereby exposing the upper surface of the resist underlayer film on which the pattern has been formed. (V-9) A step of removing the resist interlayer or hard mask interlayer remaining on the upper surface of the resist underlayer by dry etching. (V-10) A step of removing the resist underlayer film on which the exposed surface pattern is formed by dry etching, and forming an inverted pattern of the original pattern on the metal-containing film. (V-11) A step of processing the workpiece substrate using the metal-containing film on which the inverted pattern is formed as a mask to form the inverted pattern on the workpiece substrate. A pattern forming method characterized by having the following features.

19. The pattern forming method according to claim 16, characterized in that the inorganic hard mask interlayer is formed by a CVD method or an ALD method.

20. The pattern forming method according to claim 18, characterized in that the inorganic hard mask interlayer is formed by a CVD method or an ALD method.

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