Metal-containing film-forming compound, metal-containing film-forming composition, pattern-forming method, and method for producing metal-containing film-forming compound

Abstract

The invention relates to a compound for forming a metal-containing film, a composition for forming a metal-containing film, a pattern forming method, and a method for producing the compound for forming a metal-containing film. The present invention provides a method for manufacturing a semiconductor device in a fine patterning process. The present invention relates to a compound for forming a metal-containing film, a composition for forming a metal-containing film using the compound, and a method for forming a pattern using the composition, whereby it is possible to obtain a metal-containing film that has a good pattern shape, has high adhesion to a resist upper layer film, and suppresses the collapse of a fine pattern. A compound for forming a metal-containing film, characterized in that the compound for forming a metal-containing film contains at least one metal atom selected from the group consisting of Ti, Zr, and Hf, and a ligand coordinated to the metal atom, and the ligand contains any of the groups represented by (a-1) to (a-3). # imgabs0 # R1 represents a hydrogen atom or an organic group having 1-10 carbon atoms, and * represents a bonding part.

Description

Technical Field

[0001] The present invention relates to a metal-containing film-forming compound, a metal-containing film-forming composition using the compound, a pattern forming method using the composition, and a method for producing the metal-containing film-forming compound. Background Art

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

[0003] However, if the thickness of the photoresist film used is directly miniaturized, that is, if the pattern width is further reduced, the resolution performance of the photoresist film will be reduced, and if the photoresist film is to be patterned using a developer, the so-called aspect ratio will become too large, resulting in a problem of pattern collapse. Therefore, as the pattern becomes miniaturized, the photoresist film will become thinner and thinner.

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

[0005] Therefore, the substrate to be processed must be dry-etched with a thinner photoresist film with weaker etching resistance, and ensuring the materials and processing in this processing step becomes a top priority.

[0006] One method for solving such a problem is a multilayer resist method. This method is to insert a resist intermediate film having a different etching selectivity from the photoresist film (i.e., the resist upper film) between the resist upper film and the substrate to be processed, and after obtaining a pattern on the resist upper film, use the resist upper film pattern as a dry etching mask to transfer the pattern to the resist lower film by dry etching, and then use the resist lower film as a dry etching mask to transfer the pattern to the substrate to be processed by dry etching.

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

[0008] As the silicon-containing resist intermediate film used in the above-mentioned three-layer resist method, a silicon-containing inorganic film obtained by CVD, such as SiO2 film (for example: Patent Document 2, etc.), SiON film (for example: Patent Document 3, etc.) can be used. As for the film obtained by spin coating, SOG (spin-on glass) film (for example: Patent Document 4, Non-patent Document 1, etc.), cross-linked silsesquioxane film (for example: Patent Document 5, etc.), etc. can be used, and polysilane film (for example: Patent Document 6, etc.) can also be used. Among these, SiO2 film and SiON film have high performance as dry etching masks when dry etching the organic film of the lower layer, but special equipment is required for film formation. On the other hand, SOG film, cross-linked silsesquioxane film, and polysilane film can be formed by only spin coating and heating, and it is believed that the processing efficiency is high.

[0009] There are some problems with silicon-containing films used in such multilayer resist methods. For example, when a resist pattern is to be formed by optical lithography, it is known that the exposure light will be reflected by the substrate and interfere with the incident light to cause the so-called standing wave problem. In order to obtain a fine pattern without edge roughness of the resist film under the most advanced ArF immersion and high NA exposure conditions, the intermediate film needs to have an anti-reflection effect. In addition, in the most advanced semiconductor processing as mentioned above, the photoresist thin film is further advanced, so the resist intermediate film is also required to be thinner. In the next generation of exposure processing, it is required to have an anti-reflection effect with a film thickness of less than 30nm. In addition, the dry etching speed of oxygen plasma generally used during the processing of the resist lower film is preferably smaller in order to improve the etching selectivity ratio between the resist intermediate film and the resist lower film. Due to the trend of thin filmization, the dry etching resistance of the resist intermediate film is required to be improved.

[0010] As a resist interlayer film that meets the requirements for such antireflection effect and dry etching characteristics, metal hard mask films containing Ti and Zr are attracting attention instead of the known silicon-containing resist interlayer film. TiO2 and ZrO2 are known to be high refractive index materials. By containing them in the film, the antireflection effect under high NA exposure conditions can be improved. In addition, by containing metal-oxygen bonds, excellent dry etching resistance to oxygen can be expected.

[0011] In addition, since the metal-containing film has excellent dry etching resistance not only to oxygen but also to fluorine gas, a two-layer resist method can be expected in which a metal hard mask film is formed on a processed substrate as a resist lower layer film and a resist upper layer film is formed thereon.

[0012] On the other hand, when such a metal hard mask film is used directly under the resist upper film, the improvement of the adhesion with the resist pattern becomes a problem. The hardened metal hard mask film has a relatively much higher surface energy (or a smaller water contact angle) than the photoresist used subsequently. This mismatch in surface energy will cause poor adhesion between the metal-containing film and the photoresist used subsequently, and will also cause pattern collapse.

[0013] In order to suppress the collapse of the photoresist pattern on the metal hard mask film, surface modification of the metal hard mask film is necessary. For example, Patent Document 7 reports a metal hard mask film containing a surface-modified organic polymer. It is reported that by using the difference in free energy between the organic polymer and the metal compound, the organic polymer is concentrated on the surface layer, and the adhesion with the resist pattern will be improved. In order to suppress the collapse of the pattern, an organic polymer containing a surface-treated portion of a hydroxyl group, a protected hydroxyl group, a protected carboxyl group, and a mixture thereof is used. However, in the current situation where it is required to form a finer pattern, these materials cannot be said to have sufficient pattern collapse suppression performance. In addition, since it contains an organic polymer, there is a risk of deteriorating the dry etching resistance to oxygen, so it is sought to develop a metal-containing film-forming compound with excellent adhesion to the resist upper film.

[0014] It has recently been discovered that in fine patterns, the interaction between the interface between the resist upper film and the lower film directly below the resist upper film can also affect the sensitivity of the resist, the shape of the pattern (rectangularity and residue in the spacing portion), etc. From these viewpoints, the performance of the resist lower film directly below the resist upper film is also required to be improved (Non-Patent Document 2).

[0015] Prior art literature

[0016] Patent Literature

[0017] [Patent Document 1] Japanese Patent Application Publication No. 2004-205685

[0018] [Patent Document 2] Japanese Patent Application Laid-Open No. 07-183194

[0019] [Patent Document 3] Japanese Patent Application Laid-Open No. 07-181688

[0020] [Patent Document 4] Japanese Patent Application Laid-Open No. 05-291208

[0021] [Patent Document 5] Japanese Patent Publication No. 2005-520354

[0022] [Patent Document 6] Japanese Patent Application Laid-Open No. 11-060735

[0023] [Patent Document 7] Japanese Patent No. 6463600

[0024] Non-patent literature

[0025] [Non-patent document 1] J. Appl. Polym. Sci., Vol. 88, 636-640 (2003)

[0026] [Non-patent document 2] Proc. SPIE Vol. 7273, 72731J (2009) Summary of the invention

[0027] [Problems to be solved by the invention]

[0028] In view of the above situation, the present invention aims to provide a metal-containing film-forming compound and its manufacturing method, a metal-containing film-forming composition using the above-mentioned compound, and a pattern forming method using the composition, which can provide a metal-containing film that can obtain a good pattern shape and has high adhesion with the upper film of the resist and can inhibit the collapse of the fine pattern in the fine patterning process of the semiconductor device manufacturing step.

[0029] [Methods for solving problems]

[0030] In order to solve the above-mentioned problems, the present invention provides a metal-containing compound for film formation, wherein the metal-containing compound for film formation contains at least one metal atom selected from the group consisting of Ti, Zr, and Hf and a ligand coordinated to the metal atom, and the ligand contains any of the groups represented by the following formulae (a-1) to (a-3).

[0031] [Chemistry 1]

[0032]

[0033] In the formula, R1 is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and * represents a bonding portion.

[0034] If such a metal-containing film-forming compound is used in a metal-containing film-forming composition, it can form a metal-containing film having high adhesion to the resist upper film, having the effect of preventing fine pattern collapse, and being able to give a good pattern shape. In addition, the obtained metal-containing film shows a high refractive index, so it can exert a high antireflection effect under ArF immersion and high NA exposure conditions.

[0035] Furthermore, the ligand is preferably derived from a structure represented by the following general formula (1) or (2).

[0036] R a XOH(1)

[0037] R a XCOOH(2)

[0038] In the formula, R a It is any of the groups represented by the above formulae (a-1) to (a-3), and X is a divalent organic group having 1 to 20 carbon atoms.

[0039] The metal-containing film-forming compound having such a structure can achieve higher adhesion with the resist upper layer film when used in the metal-containing film-forming composition, and is more effective in preventing collapse of fine patterns.

[0040] In this case, it is preferred that the aforementioned X is a hydrocarbon group having 1 to 10 carbon atoms, or the structure represented by the aforementioned general formula (2) is a structure represented by the following general formula (x-1) or (x-2), or the structure represented by the aforementioned general formula (1) is a structure represented by the following formula (x-3).

[0041] [Chemistry 2]

[0042]

[0043] In the formula, Y1 to Y3 are divalent organic groups having 1 to 10 carbon atoms, and R a As mentioned above, n is 0 or 1, and m is 0 or 1.

[0044] [Chemistry 3]

[0045]

[0046] In the formula, Y4 is a divalent organic group having 1 to 10 carbon atoms, R a As mentioned above, l is 0 or 1.

[0047] If the ligand has such a structure, the heat resistance of the metal-containing film-forming compound is improved, and a metal-containing film containing many groups represented by the above formulae (a-1) to (a-3) can be formed, which is more effective in preventing the collapse of fine patterns.

[0048] Furthermore, Y1 to Y4 are preferably divalent hydrocarbon groups having 1 to 10 carbon atoms.

[0049] If the ligand has such a structure, the heat resistance of the metal-containing film-forming compound can be further improved.

[0050] Furthermore, the aforementioned metal-containing film-forming compound is preferably a metal compound represented by the following general formula (3), or a metal-containing compound containing any of the hydrolyzates, condensates, or hydrolysis-condensates of the metal compound represented by the following general formula (3), and a reaction product of the structure represented by the above general formula (1) or (2).

[0051] [Chemistry 4]

[0052] L a MX b (3)

[0053] In the formula, M is any one of Ti, Zr, and Hf. L is a monodentate ligand or a polydentate ligand having 1 to 30 carbon atoms, and X is selected from a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, and -NR 1 R 2 The hydrolyzable group in R 1 and R 2Each independently represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. a+b=4, and a and b are integers of 0-4.

[0054] By using such a metal-containing film-forming compound, a metal-containing film having better dry etching resistance with respect to oxygen gas can be formed.

[0055] Furthermore, the metal compound is preferably a structure represented by the following general formula (4).

[0056] M(OR 1A )4 (4)

[0057] In the formula, M is the same as above, R 1A It is a monovalent organic group having 1 to 20 carbon atoms.

[0058] A metal compound having such a structure is preferred from the viewpoint of productivity and raw material availability.

[0059] In the present invention, the metal-containing film-forming compound preferably further contains a ligand derived from a silicon compound represented by the following general formula (5).

[0060] [Chemistry 5]

[0061]

[0062] In the formula, R 3A , R 3B and R 3C , is any organic group having 2 to 30 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and an aryl group having 6 to 20 carbon atoms, which is a cross-linking group selected from any of the structures represented by the following general formulae (b-1) to (b-3).

[0063] [Chemistry 6]

[0064]

[0065] In the formula, R3 is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, q is 0 or 1, and * represents a bonding portion.

[0066] By including such a ligand, the stability of the metal-containing film-forming compound can be further improved.

[0067] The present invention also provides a metal-containing film-forming composition comprising the above-described (A) metal-containing film-forming compound and (B) an organic solvent.

[0068] Such a metal-containing film-forming composition can form a metal-containing film that has high adhesion to the resist upper layer film, has a fine pattern collapse prevention effect, and can provide a good pattern shape. In addition, the obtained metal-containing film shows a high refractive index, so it can exert a high anti-reflection effect under ArF immersion and high NA exposure conditions.

[0069] Furthermore, the metal-containing film-forming composition may contain one or more of (C) a thermal acid generator and (D) a photoacid generator.

[0070] If the metal-containing film-forming composition contains the above-mentioned additives, the metal-containing film-forming composition can have better coating properties and adhesion to the resist upper layer film.

[0071] Furthermore, the metal-containing film-forming composition may further contain one or more of (E) a cross-linking agent and (G) a surfactant.

[0072] If the metal-containing film-forming composition contains the above-mentioned additive, the metal-containing film-forming composition can be more excellent in coating properties, dry etching resistance, and filling and / or planarization properties.

[0073] Furthermore, the organic solvent (B) is preferably a mixture of one or more organic solvents having a boiling point of less than 180°C and one or more organic solvents having a boiling point of 180°C or higher.

[0074] By adding a high boiling point solvent to the metal-containing film-forming composition to impart fluidity, the occurrence of coating defects due to drying of the metal-containing film-forming composition can be suppressed.

[0075] Furthermore, the present invention provides a pattern forming method, which is a method for forming a pattern on a processed substrate, comprising the following steps:

[0076] (I-1) After applying the above-mentioned metal-containing film-forming composition on a substrate to be processed, a metal-containing film is formed by heat treatment,

[0077] (I-2) forming a resist upper layer film on the aforementioned metal-containing film using a photoresist material,

[0078] (I-3) after pattern exposure of the resist upper layer film, developing with a developer to form a pattern on the resist upper layer film,

[0079] (I-4) using the patterned resist upper layer film as a mask, transferring the pattern to the metal-containing film by dry etching, and

[0080] (I-5) The metal-containing film to which the pattern has been transferred is used as a mask to process the substrate to form a pattern on the substrate.

[0081] Furthermore, the present invention provides a pattern forming method, which is a method for forming a pattern on a processed substrate, comprising the following steps:

[0082] (II-1) forming a resist underlayer film on a substrate to be processed,

[0083] (II-2) after applying the metal-containing film-forming composition on the resist underlayer film, forming a metal-containing film by heat treatment,

[0084] (II-3) forming a resist upper layer film on the aforementioned metal-containing film using a photoresist material,

[0085] (II-4) after pattern exposure of the resist upper layer film, developing with a developer to form a pattern on the resist upper layer film,

[0086] (II-5) using the patterned resist upper layer film as a mask, transferring the pattern to the metal-containing film by dry etching,

[0087] (II-6) using the metal-containing film to which the pattern has been transferred as a mask, transferring the pattern to the resist underlayer film by dry etching, and

[0088] (II-7) The substrate to be processed is processed using the resist underlayer film to which the pattern has been transferred as a mask to form a pattern on the substrate to be processed.

[0089] Thus, the metal-containing film-forming compound of the present invention is a metal-containing film-forming compound containing a group selected from the above formulas (a-1) to (a-3). When used in a metal-containing film-forming composition, it can form a metal-containing film with excellent adhesion to the resist upper film, so it is suitable for use in various pattern forming methods such as two-layer resist processing and three-layer resist processing. In these pattern forming methods, the metal-containing film provided by the present invention can be used to effectively suppress pattern collapse, which is suitable for optical lithography of the resist upper film, and the resist upper film pattern can be transferred to the processed substrate with high precision.

[0090] The present invention also provides a method for producing a metal-containing film-forming compound, which comprises reacting a metal compound containing at least one metal atom selected from the group consisting of Ti, Zr, and Hf, and a ligand containing any of the groups represented by the following formulae (a-1) to (a-3).

[0091] [Chemistry 7]

[0092]

[0093] In the formula, R1 is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and * represents a bonding portion.

[0094] If such a method for producing a metal-containing film-forming compound is used, it is easy to produce a metal-containing film-forming compound used in a metal-containing film-forming composition that can form a metal-containing film that has high adhesion with the upper film of the resist and has the effect of preventing the collapse of the fine pattern and giving a good pattern shape.

[0095] In this case, the ligand preferably has a structure represented by the following general formula (1) or (2).

[0096] R a XOH(1)

[0097] R a XCOOH(2)

[0098] In the formula, R a It is any of the groups represented by the above formulae (a-1) to (a-3), and X is a divalent organic group having 1 to 20 carbon atoms.

[0099] By using such a ligand, when used in a metal-containing film-forming composition, a metal-containing film-forming compound can be produced which can obtain higher adhesion with a resist upper layer film and more effectively prevent collapse of a fine pattern.

[0100] Furthermore, the aforementioned ligand is preferably one in which the aforementioned X is a hydrocarbon group having 1 to 10 carbon atoms, or the structure represented by the aforementioned general formula (2) is a structure represented by the following general formula (x-1) or (x-2), or the structure represented by the aforementioned general formula (1) is a structure represented by the following formula (x-3).

[0101] [Chemistry 8]

[0102]

[0103] In the formula, Y1 to Y3 are divalent organic groups having 1 to 10 carbon atoms, and R a As mentioned above, n is 0 or 1, and m is 0 or 1.

[0104] [Chemistry 9]

[0105]

[0106] In the formula, Y4 is a divalent organic group having 1 to 10 carbon atoms, R a As mentioned above, l is 0 or 1.

[0107] By using a ligand having such a structure, heat resistance is improved, a metal-containing film containing many groups represented by the above formulae (a-1) to (a-3) can be formed, and a metal-containing film-forming compound that is more effective in preventing collapse of fine patterns can be produced.

[0108] In addition, it is preferred that Y1 to Y4 be a divalent hydrocarbon group having 1 to 10 carbon atoms.

[0109] By using a ligand having such a structure, a metal-containing film-forming compound having further improved heat resistance can be produced.

[0110] Furthermore, with respect to the aforementioned metal-containing film-forming compound, it is preferred to use a metal compound represented by the following general formula (3), or a metal-containing compound containing any of the hydrolyzates, condensates, or hydrolysis-condensates of the metal compound represented by the following general formula (3), and a reaction product of the structure represented by the above general formula (1) or (2).

[0111] [Chemistry 10]

[0112] L a MX b (3)

[0113] In the formula, M is any one of Ti, Zr, and Hf. L is a monodentate ligand or a polydentate ligand having 1 to 30 carbon atoms, and X is selected from a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, and -NR 1 R 2 The hydrolyzable group in R 1 and R 2 Each independently represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. a+b=4, and a and b are integers of 0-4.

[0114] By using such a metal-containing film-forming compound, a metal-containing film having better dry etching resistance with respect to oxygen gas can be formed.

[0115] In this case, the metal compound preferably has a structure represented by the following general formula (4).

[0116] M(OR 1A )4 (4)

[0117] In the formula, M is the same as above, R 1A It is a monovalent organic group having 1 to 20 carbon atoms.

[0118] Use of a metal compound having such a structure is preferred from the viewpoint of productivity and raw material availability.

[0119] (Effects of the Invention)

[0120] As described above, the present invention provides a metal-containing film-forming compound having high adhesion to a resist upper layer film and an effect of suppressing collapse of a fine pattern, a method for producing the same, a metal-containing film-forming composition using the above-mentioned compound, and a pattern forming method using the composition.

[0121] The metal-containing film formed using the known metal-containing film-forming compound has a much higher surface energy (or a smaller water contact angle) than the photoresist film used subsequently, so the mismatch in surface energy may cause poor adhesion between the metal-containing film and the photoresist film used subsequently, resulting in pattern collapse. In addition, when an organic polymer is mixed as a surface modifier, the dry etching resistance of the metal-containing film during processing is insufficient, which may induce poor pattern transfer.

[0122] On the other hand, the metal-containing film-forming compound of the present invention contains any of the groups represented by the above formulas (a-1) to (a-3), so when used in a metal-containing film-forming composition, a metal-containing film having excellent adhesion to the resist upper film can be formed. Therefore, it has an effect of suppressing the collapse of fine patterns, and gives a pattern shape of the resist upper film with high rectangularity to the processed substrate, which is very useful in multilayer resist processing. In addition, the metal-containing film-forming composition of the present invention has excellent resistance to dry etching using oxygen and fluorine gas, respectively, so in various pattern forming methods such as two-layer resist processing and three-layer resist processing, a fine pattern can be formed on the processed substrate with high precision. BRIEF DESCRIPTION OF THE DRAWINGS

[0123] Figure 1 (A) to (F) are explanatory diagrams of an example (three-layer resist process) of the pattern forming method of the present invention.

[0124] Figure 2 (G) to (K) are explanatory diagrams of an example of the pattern forming method of the present invention (two-layer resist processing).

[0125] Figure 3 Illustration of reflectance calculation for the pattern forming method. DETAILED DESCRIPTION

[0126] As described above, in the development of fine patterning processing in the semiconductor device manufacturing steps, there are provided metal-containing film-forming compounds and their manufacturing methods, metal-containing film-forming compositions using the aforementioned compounds, and pattern forming methods using the compositions.

[0127] The inventors of the present application have made great efforts to study the above-mentioned problems and have found that the above-mentioned problems can be solved by providing a metal-containing film-forming compound containing a ligand with a specific structure as shown below and a method for producing the same, a metal-containing film-forming composition using the above-mentioned compound, and a pattern forming method using the composition, thereby completing the present invention.

[0128] That is, the present invention is a metal-containing compound for film formation, wherein the metal-containing compound for film formation contains at least one metal atom selected from the group consisting of Ti, Zr, and Hf and a ligand coordinated to the metal atom, and the ligand contains any of the groups represented by the following formulae (a-1) to (a-3).

[0129] [Chemistry 11]

[0130]

[0131] In the formula, R1 is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and * represents a bonding portion.

[0132] The present invention is described in detail below, but the present invention is not limited thereto.

[0133] [(A) Metal-Containing Film-Forming Compound]

[0134] The present invention is a metal-containing compound for film formation, wherein the metal-containing compound for film formation contains at least one metal atom selected from the group consisting of Ti, Zr, and Hf and a ligand coordinated to the metal atom, and the ligand contains any of the groups represented by the following formulae (a-1) to (a-3).

[0135] [Chemistry 12]

[0136]

[0137] In the formula, R1 is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and * represents a bonding portion.

[0138] By containing such a heterocyclic structure, the epoxy or oxetane structure undergoes a ring-opening reaction during film formation by heating, thereby hardening the film. In addition, the hydroxyl groups generated by this ring-opening reaction also contribute to improving the adhesion with the resist upper layer film.

[0139] R1 in the above formula (a-3) is a hydrogen atom or an organic group having 1 to 10 carbon atoms, preferably a hydrogen atom, a methyl group or an ethyl group, more preferably an ethyl group.

[0140] The aforementioned ligand is preferably derived from a structure represented by the following general formula (1) or (2).

[0141] R a XOH(1)

[0142] R a XCOOH(2)

[0143] In the formula, R a It is any of the groups represented by the above formulae (a-1) to (a-3), and X is a divalent organic group having 1 to 20 carbon atoms.

[0144] In the above formula, X may contain one or more selected from a divalent organic group having 1 to 20 carbon atoms, an oxygen atom, a nitrogen atom, and a sulfur atom.

[0145] If the ligand contained in the metal-containing film-forming compound is derived from the above structure, it is more preferable from the viewpoint of the productivity of the metal-containing film-forming compound. In addition, since a metal-containing film-forming compound having a ligand containing any of the groups represented by formulae (a-1) to (a-3) is provided, it is more preferable from the viewpoint of obtaining raw materials.

[0146] In addition, the aforementioned X is a hydrocarbon group having 1 to 10 carbon atoms, or the structure represented by the aforementioned general formula (2) is a structure represented by the following general formula (x-1) or (x-2), or the structure represented by the aforementioned general formula (1) is a structure represented by the following formula (x-3)

[0147] [Chemistry 13]

[0148]

[0149] In the formula, Y1 to Y3 are divalent organic groups having 1 to 10 carbon atoms, and R a As mentioned above, n is 0 or 1, and m is 0 or 1.

[0150] [Chemistry 14]

[0151]

[0152] In the formula, Y4 is a divalent organic group having 1 to 10 carbon atoms, R a As mentioned above, l is 0 or 1.

[0153] It is more preferable that Y1 to Y4 are divalent hydrocarbon groups having 1 to 10 carbon atoms from the viewpoint of heat resistance.

[0154] As specific examples of the structure represented by the general formula (x-1), the following structures are mentioned as preferred examples.

[0155] [Chemistry 15]

[0156]

[0157] In the formula, R a Same as above.

[0158] Specific examples of the structure represented by the general formula (x-2) include the following structures as preferred examples.

[0159] [Chemistry 16]

[0160]

[0161] In the formula, R a As mentioned above, Rx It is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms.

[0162] Specific examples of the structure represented by the general formula (x-3) include the following structures as preferred examples.

[0163] [Chemistry 17]

[0164]

[0165] In the formula, R a As mentioned above, m is 0-4.

[0166] In the above general formula (x-2), R a A group represented by the formula (a-3) is more preferred from the viewpoint of raw material availability.

[0167] The aforementioned metal-containing film-forming compound is preferably a metal compound represented by the following general formula (3), or a metal-containing compound containing any of the hydrolyzates, condensates, or hydrolysis-condensates of the metal compound represented by the following general formula (3), and a reaction product of the structure represented by the above general formula (1) or (2).

[0168] [Chemistry 18]

[0169] L a MX b (3)

[0170] In the formula, M is any one of Ti, Zr, and Hf. L is a monodentate ligand or a polydentate ligand having 1 to 30 carbon atoms, and X is selected from a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, and -NR 1 R 2 The hydrolyzable group in R 1 and R 2 Each independently represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. a+b=4, and a and b are integers of 0-4.

[0171] When such a metal-containing film-forming compound is used in a metal-containing film-forming composition, a metal-containing film having excellent dry etching resistance to oxygen gas can be formed.

[0172] [(a) Metal compounds, metal-containing compounds]

[0173] (Hydrolyzable Group)

[0174] The hydrolyzable group X in the general formula (3) is, for example, selected from a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, and -NR 1 R 2 One or more of the following. 1 and R 2Each independently represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms.

[0175] The above-mentioned halogen atom includes, for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like.

[0176] The above-mentioned alkoxy group includes, for example, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, tert-butoxy and the like.

[0177] The above-mentioned carboxylate group includes, for example, acetate group, propionate group, butyrate group, n-hexanecarboxylate group, n-octanecarboxylate group and the like.

[0178] Examples of the acyloxy group include acetyloxy, acetyloxy, propionyloxy, butyryloxy, tert-butyryloxy, tert-valeryloxy, n-hexanecarbonyloxy and n-octanecarbonyloxy groups.

[0179] Above-NR 1 R 2 , such as unsubstituted amino, methylamino, dimethylamino, diethylamino, dipropylamino and the like.

[0180] The hydrolyzable group X is preferably an alkoxy group, more preferably an isopropoxy group, an n-butoxy group, or a tert-butoxy group.

[0181] (monodentate ligand)

[0182] The above-mentioned monodentate ligands include, for example, hydroxyl ligands, carboxyl ligands, amide ligands, amine ligands, amino ligands, olefin ligands and the like.

[0183] The above-mentioned carboxyl ligands, for example, formate ligand (OOCH), acetate ligand (OOCMe), propionate ligand (OOCEt), butyrate ligand (OOCPr).

[0184] The above-mentioned amide ligands include, for example, unsubstituted amide ligand (NH2), methylamide ligand (NHMe), dimethylamide ligand (NMe2), diethylamide ligand (NEt2), dipropylamide ligand (NPr2) and the like.

[0185] The above-mentioned amine ligands include, for example, pyridine, trimethylamine ligands, piperidine ligands and the like.

[0186] Olefin ligands, for example, chain olefins such as ethylene and propylene, cyclic olefins such as cyclopentene, cyclohexene, and norbornene, etc.

[0187] (Multidentate Ligand)

[0188] The above-mentioned multidentate ligands include, for example, ligands derived from hydroxy acid esters, ligands derived from β-diketones, ligands derived from β-ketoesters, ligands derived from α,α-dicarboxylates, hydrocarbons having π bonds, biphosphines, and the like.

[0189] The above-mentioned hydroxy acid esters include glycolic acid esters, lactic acid esters, 2-hydroxycyclohexane-1-carboxylic acid esters, salicylic acid esters and the like.

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

[0191] The above-mentioned β-diketone includes, for example, acetylacetone, methylacetylacetone, and ethylacetylacetone.

[0192] The above-mentioned α,α-dicarboxylic acid esters include, for example, malonic acid diesters, α-alkyl-substituted malonic acid diesters, α-cycloalkyl-substituted malonic acid diesters, α-aryl-substituted malonic acid diesters, and the like.

[0193] The above-mentioned hydrocarbons having a π bond include, for example, chain dienes such as butadiene and isoprene, cyclic dienes such as cyclopentadiene, methylcyclopentadiene, pentamethylcyclopentadiene, cyclohexadiene, and norbornadiene, and aromatic hydrocarbons such as benzene, toluene, xylene, hexamethylbenzene, naphthalene, and indene.

[0194] The above-mentioned biphosphine is, for example, 1,1-bis(diphenylphosphino)methane, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl, 1,1'-bis(diphenylphosphino)ferrocene, and the like.

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

[0196] The above-mentioned (a) metal compounds and metal-containing compounds include, for example, titanium-containing compounds such as diisopropoxybis(2,4-pentanedionato)titanium(IV), tetra-n-butoxytitanium(IV), tetra-n-propoxytitanium(IV), tri-n-butoxymonostearatetitanium(IV), butoxytitanium(IV) oligomer, aminopropyltrimethoxytitanium(IV), triethoxymono(2,4-pentanedionato)titanium(IV), tri-n-propoxymono(2,4-pentanedionato)titanium(IV), triisopropoxymono(2,4-pentanedionato)titanium, di-n-butoxybis(2,4-pentanedionato)titanium(IV), and the like; zirconium-containing compounds such as dibutoxybis(ethylacetoacetate)zirconium(IV), di-n-butoxybis(2,4-pentanedionato)zirconium(IV), tetra-n-butoxyzirconium(IV), tetra-n-propoxyzirconium(IV) , tetraisopropoxy zirconium (IV), aminopropyl triethoxy zirconium (IV), 2-(3,4-epoxycyclohexyl)ethyl trimethoxy zirconium (IV), γ-glycidoxypropyl trimethoxy zirconium (IV), 3-isocyanopropyl trimethoxy zirconium (IV), triethoxymono(2,4-pentanedionate) zirconium (IV), tri-n-propoxymono(2,4-pentanedionate) zirconium (IV), triisopropoxymono(2,4-pentanedionate) zirconium (IV), tri(3-methacryloxypropyl)methoxy zirconium (IV), tri(3-acryloxypropyl)methoxy zirconium (IV), etc., and as for the hafnium-containing compounds, for example, diisopropoxybis(2,4-pentanedionate) hafnium (IV), tetrabutoxy hafnium (IV), tetraisopropoxy hafnium (IV), tetraethoxy hafnium (IV), dichlorobis(cyclopentadienyl) hafnium (IV), etc.

[0197] From the viewpoint of raw material availability, the metal compound preferably has a structure represented by the following general formula (4).

[0198] M(OR 1A )4(4)

[0199] In the formula, M is the same as above, R 1A It is a monovalent organic group having 1 to 20 carbon atoms.

[0200] In the above general formula (4), R 1A It is a monovalent organic group having 1 to 20 carbon atoms, preferably methyl, ethyl, n-propyl, isopropyl, n-butyl or tert-butyl, and more preferably isopropyl, n-butyl or tert-butyl.

[0201] During the synthesis reaction of the metal-containing film-forming compound, in addition to the (a) metal compound, the metal-containing compound and the structure containing any of the groups represented by the formulae (a-1) to (a-3), a compound that may become a monodentate ligand or a polydentate ligand in the metal-containing film-forming compound (hereinafter referred to as (b) the ligand-forming compound) may also be added.

[0202] The above-mentioned (b) ligand-forming compounds include, for example, organic compounds derived from hydroxyl ligands, carboxyl ligands, amide ligands, amine ligands, amino ligands, olefin ligands, etc. listed for L in the above-mentioned general formula (3), ligands derived from hydroxy acid esters, ligands derived from β-diketones, ligands derived from β-ketoesters, ligands derived from α,α-dicarboxylates, etc. In addition, compounds having multiple hydroxyl groups can be listed.

[0203] Furthermore, the ligand-forming compound (b) may be an organic compound having 1 to 30 carbon atoms and containing at least one cross-linking group represented by any of the following general formulae (c-1) to (c-4), (d-1) to (d-4), and (e-1) to (e-3).

[0204] [Chemistry 19]

[0205]

[0206] In the formula, R c is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, q' represents 0 or 1, and * represents a bonding portion.

[0207] [Chemistry 20]

[0208]

[0209] In the formula, R d1 is a hydrogen atom or a methyl group, which may be the same or different from each other in the same formula, and R d2 It is a hydrogen atom, a substituted or unsubstituted saturated or unsaturated monovalent organic group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted arylalkyl group having 7 to 31 carbon atoms; * represents a bonding portion.

[0210] [Chemistry 21]

[0211]

[0212] Where Y e is a divalent organic group having 1 to 20 carbon atoms, R e2 is a hydrogen atom, a substituted or unsubstituted saturated divalent organic group having 1 to 20 carbon atoms or an unsaturated divalent organic group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted arylalkyl group having 7 to 31 carbon atoms, R e1 It is an organic group represented by the following general formula (e-4), in which the protecting group is released by the action of either acid, heat, or both to generate one or more hydroxyl groups or carboxyl groups, and * represents a bonding part.

[0213] [Chemistry 22]

[0214]

[0215] In the formula, R e3 is an organic group whose protecting group is removed by the action of acid, heat, or both, and * represents e The bonding portion.

[0216] The metal-containing film-forming compound contains at least one cross-linking group represented by any of the above-mentioned general formulas (c-1) to (c-4), (d-1) to (d-4), and (e-1) to (e-3), and can obtain sufficient thermal fluidity during film formation. Therefore, when used in a metal-containing film-forming composition, a metal-containing film with excellent flatness can be formed.

[0217] From the viewpoint of the productivity and stability of the metal-containing film-forming compound, the above-mentioned (b) ligand-forming compound is preferably a compound derived from a carboxyl ligand, a compound derived from a ligand of β-diketone, or a compound having multiple hydroxyl groups. They can be used alone or in combination of two or more.

[0218] The compound derived from the carboxyl ligand is, for example, a compound represented by the following general formula (5').

[0219] [Chemistry 23]

[0220]

[0221] Where p is 0 or 1. When p is 1, X 1 is a divalent organic group having 2 to 20 carbon atoms, W is an alkoxy group having 1 to 10 carbon atoms, the following general formula (5-A), and any of the crosslinking groups represented by the general formulas (d-1) to (d-4). When p is 0, X 1 It is a monovalent organic group having 8 to 30 carbon atoms and a crosslinking group of any one of the structures represented by the above general formulae (c-2) and (c-3) and an aromatic ring.

[0222] [Chemistry 24]

[0223]

[0224] In the formula, Y is a saturated or unsaturated h+1 organic group having 1 to 20 carbon atoms, and R A It is any one of the crosslinking groups represented by the above general formulae (c-1) to (c-4), h represents 1 to 6, and * represents a bonding portion to the carbon atom of the carbonyl group.

[0225] If the metal-containing film-forming compound contains a carboxyl ligand having such a structure, the heat curing property when used as a metal-containing film-forming composition is improved, and a metal-containing film having excellent mixing resistance with a resist upper layer film can be formed.

[0226] In the above general formula (5'), p is 1, and W is preferably a structure represented by the following general formula (5-B-1) or (5-B-2).

[0227] [Chemistry 25]

[0228]

[0229] In the formula, R A1 is a cross-linking group represented by the above general formula (c-1), R A2 is a crosslinking group represented by the above general formula (c-2) or (c-3), Z is an oxygen atom or a secondary amine, L 1 is a divalent hydrocarbon group having 1 to 10 carbon atoms, R A3 It is a saturated or unsaturated monovalent organic group having 1 to 20 carbon atoms or 2 to 20 carbon atoms. u is 0 or 1. When u is 0, t is 1 to 5, s is 0 to 4, and t+s is 1 to 5. When u is 1, t is 1 to 6, s is 0 to 5, and t+s is 1 to 6. r is 1 to 10, m is 0 or 1, and * represents a bond to the carbon atom of the carbonyl group.

[0230] If the metal-containing film-forming compound contains a carboxyl ligand with such a structure, the heat resistance of the metal-containing film-forming composition is improved, so the formed metal-containing film shows excellent film-forming properties, and the generation of sublimates during heat curing can be suppressed to prevent device contamination.

[0231] In the above general formula (5'), p is 1, W is an alkoxy group having 1 to 10 carbon atoms, and X 1 Any of the structures represented by the following general formula (5-C) is preferred.

[0232] [Chemistry 26]

[0233]

[0234] In the formula, * represents a bonding portion to the carbon atom of the carbonyl group.

[0235] If the metal-containing film-forming compound contains a carboxyl ligand with such a structure, the heat resistance of the metal-containing film-forming composition is improved, so the formed metal-containing film shows excellent film-forming properties, and the occurrence of sublimates during heat curing can be suppressed, thereby suppressing device contamination.

[0236] Or in the above general formula (5'), p is 0, X 1 Any of the structures represented by the following formula (5-D) is preferred.

[0237] [Chemistry 27]

[0238]

[0239] In the formula, R f It is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, and * represents a bonding portion to the carbon atom of the carbonyl group.

[0240] Other examples of the compound derived from the carboxyl ligand include compounds represented by the following general formula (6).

[0241] [Chemistry 28]

[0242]

[0243] Where, X 2 is a divalent organic group having 1 to 31 carbon atoms, R 6A It is any of the above-mentioned general formulae (e-1) to (e-3).

[0244] In the above general formula (6), X 2 It is a divalent organic group having 1 to 31 carbon atoms, and is more preferably a saturated hydrocarbon group having 1 to 20 carbon atoms or an unsaturated hydrocarbon group having 2 to 20 carbon atoms from the viewpoint of thermosetting properties.

[0245] In the above general formulas (e-1) to (e-3), Y e is a substituted or unsubstituted saturated or unsaturated divalent 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, Y e It is preferably a saturated hydrocarbon group having 1 to 20 carbon atoms or an unsaturated hydrocarbon group having 2 to 20 carbon atoms.

[0246] In the above general formulas (e-1) to (e-3), if Y e A saturated hydrocarbon group having 1 to 20 carbon atoms or an unsaturated hydrocarbon group having 2 to 20 carbon atoms can further improve the heat curing property of the metal-containing film-forming compound when it is made into a metal-containing film-forming composition. This is also preferable from the viewpoint of raw material availability.

[0247] Y e Examples include, but are not limited to, the following structures.

[0248] [Chemistry 29]

[0249]

[0250] *1 is the bond with oxygen or nitrogen atom, *2 is the bond with R e1 The bonding portion.

[0251] In the above general formula (e-4), R e3 The organic group whose protecting group is released by the action of either acid or heat or both is preferably a tertiary hydrocarbon group or a group forming an acetal structure with an adjacent oxygen atom, and a tertiary hydrocarbon group is particularly preferred. The tertiary hydrocarbon group preferably has 4 to 20 carbon atoms, and the one with fewer carbon atoms is more preferred.

[0252] The compound derived from the ligand of β-diketone is, for example, a compound represented by the following general formula (7).

[0253] [Chemistry 30]

[0254]

[0255] In the formula, R 7A ~R 7c A monovalent organic group having 1 to 20 carbon atoms which is a hydrogen atom or may contain a crosslinking group represented by any of the general formulae (c-1) to (c-4) and (d-1) to (d-4).

[0256] The compound of the general formula (7) preferably contains at least one crosslinking group represented by any of the general formulae (c-1) to (c-4) and (d-1) to (d-4). Such a compound is preferred because the thermal curing performance of the metal-containing film-forming compound when it is made into a metal-containing film-forming composition is further improved.

[0257] Examples of the compound having a plurality of hydroxyl groups include divalent alcohols represented by any of the following general formulae (7-A) to (7-C).

[0258] [Chemistry 31]

[0259]

[0260] In the formula, R 7a ~R 7b is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms which may contain a crosslinking group represented by any of the general formulae (c-1) to (c-4), R 7c ~R 7f is a hydrogen atom, or a monovalent organic group having 1 to 20 carbon atoms which may contain a crosslinking group represented by any of the general formulae (c-1) to (c-4) and (d-1) to (d-4), 2 is a divalent organic group having 1 to 10 carbon atoms. 7a With R 7b They may also bond with each other to form an unsaturated or saturated ring structure.

[0261] The compounds of the general formulae (7-A) to (7-C) preferably contain at least one crosslinking group represented by any of the general formulae (c-1) to (c-4) and (d-1) to (d-4). Such compounds are preferred because the thermal curing performance of the metal-containing film-forming compound when used as a metal-containing film-forming composition is further improved.

[0262] In the metal-containing film-forming compound, the content of the ligand containing any of the groups represented by formulas (a-1) to (a-3) is preferably 10 mol% to 90 mol% of the total content of the ligands coordinated to the metal atom, more preferably 20 mol% to 80 mol%, and even more preferably 25 mol% to 75 mol%. The content of the ligand from the (b) ligand-forming compound is preferably 0 mol% to 50 mol% of the total content of the ligands coordinated to the metal atom, and more preferably 0 mol% to 30 mol%. The ligand other than the (b) ligand-forming compound, such as the ligand from the alkoxy group having 1 to 10 carbon atoms, is preferably 0 mol% to 90 mol% of the total content of the ligands coordinated to the metal atom, and more preferably 20 mol% to 80 mol%.

[0263] Furthermore, in the synthesis reaction of the metal-containing film-forming compound, in addition to (a) the metal compound, the metal-containing compound and the structure containing any of the groups represented by formulae (a-1) to (a-3), (c) a silicon-containing compound may be added.

[0264] By substituting the hydrolyzable group of the (a) metal compound or the metal-containing compound with the (c) silicon-containing compound, the stability of the metal-containing film-forming compound in the metal-containing film-forming composition can be improved.

[0265] That is, it is preferred that the metal-containing film-forming compound further contains a ligand derived from a silicon compound represented by the following general formula (5).

[0266] [Chemistry 32]

[0267]

[0268] In the formula, R 3A , R 3B and R 3C , is any organic group having 2 to 30 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and an aryl group having 6 to 20 carbon atoms, which is a cross-linking group selected from any of the structures represented by the following general formulae (b-1) to (b-3).

[0269] [Chemistry 33]

[0270]

[0271] In the formula, R3 is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, q is 0 or 1, and * represents a bonding portion.

[0272] The silicon-containing compound is preferably any compound of the following formula, and trimethylsilanol is more preferable from the viewpoint of productivity.

[0273] [Chemistry 34]

[0274]

[0275] When the metal-containing film-forming compound contains a ligand derived from any of the groups represented by formulae (a-1) to (a-3) and a ligand derived from a silicon-containing compound (c), the content of the ligand derived from any of the groups represented by formulae (a-1) to (a-3) in the metal-containing film-forming compound is preferably 10 mol% to 90 mol% of the total content of the ligands coordinated to the metal atom, more preferably 20 mol% to 80 mol%, and even more preferably 25 mol% to 75 mol%. The content of the ligand derived from the silicon-containing compound (c) is preferably 10 mol% to 90 mol% of the total content of the ligands coordinated to the metal atom, and more preferably 20 mol% to 80 mol%. The total content of ligands other than ligands from the silicon-containing compound (c), such as ligands from an alkoxy group having 1 to 10 carbon atoms coordinated to the metal atom is preferably 0 mol % to 90 mol %, and more preferably 20 mol % to 80 mol %.

[0276] [Method for producing a metal-containing film-forming compound]

[0277] The present invention also provides a method for producing a metal-containing film-forming compound, which comprises reacting a metal compound containing at least one metal atom selected from the group consisting of Ti, Zr, and Hf, and a ligand containing any of the groups represented by the above formulae (a-1) to (a-3).

[0278] In this case, it is preferable to use a ligand having a structure represented by the above general formula (1) or (2).

[0279] In addition, the aforementioned ligand is preferably a structure in which the aforementioned X is a hydrocarbon group having 1 to 10 carbon atoms, or the structure represented by the aforementioned general formula (2) is a structure represented by the aforementioned general formula (x-1) or (x-2), or the structure represented by the aforementioned general formula (1) is a structure represented by the aforementioned formula (x-3).

[0280] In this case, it is preferred that Y1 to Y4 be a divalent hydrocarbon group having 1 to 10 carbon atoms.

[0281] Furthermore, the aforementioned metal-containing film-forming compound is preferably a reaction product of a metal compound represented by the above-mentioned general formula (3), or a metal-containing compound containing any of the hydrolyzate, condensate, or hydrolysis-condensate of the metal compound represented by the above-mentioned general formula (3), and a structure represented by the above-mentioned general formula (1) or (2).

[0282] In this case, the metal compound preferably has a structure represented by the above general formula (4).

[0283] The metal compound used in the present invention is not particularly limited as long as it contains at least one metal atom selected from the group consisting of Ti, Zr, and Hf.

[0284] When synthesizing a metal-containing film-forming compound containing a ligand containing any of the groups represented by formulae (a-1) to (a-3), the metal-containing film-forming compound only needs to contain a ligand containing any of the groups represented by formulae (a-1) to (a-3), and the synthesis method is not particularly limited. For example, the (a) metal compound or the metal-containing compound may be a metal alkoxide or a metal acetylacetonate (acac), which can be obtained by reacting a metal alkoxide or a metal acac with a ligand containing any of the groups represented by formulae (a-1) to (a-3). The (a) metal compound may be hydrolyzed and condensed, and then reacted with a ligand containing any of the groups represented by formulae (a-1) to (a-3), or the (a) metal compound may be reacted with a ligand containing any of the groups represented by formulae (a-1) to (a-3) and then hydrolyzed and condensed. When the hydrolysis condensation is difficult to control, the ligand containing any of the groups represented by formulae (a-1) to (a-3) may be reacted in a non-aqueous environment. It is preferable to adjust them appropriately in accordance with the properties required for the metal-containing film-forming compound and the metal-containing film. When the ligand is a ligand from a silicon-containing compound (c) and a ligand containing any of the groups represented by formulae (a-1) to (a-3), it is preferable to react the metal compound, the metal-containing compound and the silicon-containing compound (c) with the ligand containing any of the groups represented by formulae (a-1) to (a-3).

[0285] A method for hydrolysis-condensation reaction using (a) metal compound, for example, a method for hydrolysis-condensation reaction of (a) metal compound in a water-containing solvent. In this case, other compounds with hydrolyzable groups may be added as needed. In addition, acids such as acetic acid may be added as catalysts for hydrolysis-condensation reaction. The lower limit of the amount of water used in this hydrolysis-condensation reaction is 0.2 times mole, preferably 1 times mole, and more preferably 3 times mole relative to the hydrolyzable groups possessed by (a) metal compound, etc. The upper limit of the amount of the above-mentioned water is 20 times mole, preferably 15 times mole, and more preferably 10 times mole.

[0286] The solvent used in the synthesis reaction of the metal-containing film-forming compound is not particularly limited, and for example, the same solvent as that exemplified in the following (B) organic solvent can be used. Typical solvents and solvent mixtures are those containing ester, ether or alcohol functional groups, for example: a mixture of propylene glycol monomethyl ether acetate (PGMEA) and propylene glycol monomethyl ether (PGME) in a volume ratio of 70 / 30. Other solvents that can be used include butanediol monomethyl ether, ethylene glycol monomethyl ether, butanediol monoethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, butanediol monopropyl ether, propylene glycol monopropyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, propylene glycol monobutyl ether, 1-butanol, 2-butanol, 2-methyl-1-propanol, 4-methyl-2-pentanol, Acetone, tetrahydrofuran, toluene, hexane, ethyl acetate, cyclohexanone, methyl amyl ketone, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, diamyl ether, isoamyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, propylene glycol monotert-butyl ether acetate, γ-butyrolactone, methyl isobutyl ketone, cyclopentyl methyl ether, etc.

[0287] [Metal-Containing Film-Forming Composition]

[0288] The present invention also provides a metal-containing film-forming composition comprising the above-described (A) metal-containing film-forming compound and (B) an organic solvent.

[0289] At this time, the metal-containing film-forming composition preferably contains one or more of (C) a thermal acid generator and (D) a photoacid generator, and the metal-containing film-forming composition preferably contains one or more of (E) a crosslinking agent and (G) a surfactant.

[0290] Hereinafter, each component contained in the metal-containing film-forming composition of the present invention will be described in detail.

[0291] [(B) Organic solvent]

[0292] 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 can dissolve or disperse the above-mentioned (A) metal-containing film-forming compound and the (C) thermal acid generator, (D) photoacid generator, (E) cross-linking agent, (G) surfactant, and other additives that are optionally contained therein.

[0293] Specifically, for example, an organic solvent described in paragraphs

[0091] to

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

[0294] The amount of the organic solvent (B) to be added is preferably in the range of 200 to 10,000 parts by mass, more preferably 250 to 5,000 parts by mass, based on 100 parts by mass of the metal-containing film-forming compound (A).

[0295] The (B) organic solvent may be 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. In the present invention, an organic solvent having a boiling point of 180° C. or higher may be referred to as a high boiling point organic solvent.

[0296] The high boiling point organic solvent may be any solvent capable of dissolving or dispersing the components of the metal-containing film-forming composition of the present invention, and is not particularly limited to hydrocarbons, alcohols, ketones, esters, ethers, chlorine-based solvents, and the like. Specific examples thereof include 1-octanol, 2-ethylhexanol, 1-nonanol, 1-decanol, 1-undecanol, ethylene glycol, 1,2-propylene glycol, 1,3-butanediol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,5-hexanediol, 2,4-heptanediol, 2-ethyl-1,3 -Hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, glycerol, n-nonyl acetate, monohexyl ether, ethylene glycol mono-2-ethylhexyl ether, ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, diethylene glycol monoethyl ether, diethylene glycol monoisopropyl ether, diethylene glycol mono-n-butyl ether, diethylene glycol monoisobutyl ether, diethylene glycol monohexyl ether, diethylene glycol monophenyl ether, diethylene glycol monobenzyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol monomethyl ether, triethylene glycol Ethylene glycol-n-butyl ether, triethylene glycol butyl methyl ether, tetraethylene glycol dimethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-n-butyl ether, tripropylene glycol dimethyl ether, tripropylene glycol monomethyl ether, tripropylene glycol mono-n-propyl ether, tripropylene glycol mono-n-butyl ether, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, triacetin, propylene glycol diacetate , dipropylene glycol methyl-n-propyl ether, dipropylene glycol methyl ether acetate, 1,4-butanediol diacetate, 1,3-butanediol diacetate, 1,6-hexanediol diacetate, triethylene glycol diacetate, γ-butyrolactone, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, dihexyl malonate, diethyl succinate, dipropyl succinate, dibutyl succinate, dihexyl succinate, dimethyl adipate, diethyl adipate, dibutyl adipate, etc., which can be used alone or in combination.

[0297] The high boiling point organic solvent can be appropriately selected from the above range, for example, in accordance with the temperature at which the metal-containing film-forming composition of the present invention is heat-treated. The boiling point of the high boiling point organic solvent is preferably 180°C to 300°C, and more preferably 200°C to 300°C. If the boiling point is such, the volatilization rate during baking (heat treatment) will be appropriate, so that the defects caused by drying during film formation can be suppressed. In addition, if the boiling point is such, it will volatilize after baking and will not remain in the film, so it has no effect on the film properties such as etching resistance.

[0298] When a high boiling point organic solvent is used, the blending amount is preferably 1 to 30 parts by mass relative to 100 parts by mass of the organic solvent having a boiling point of less than 180° C. Such a blending amount is desirable because sufficient thermal fluidity can be imparted during baking and no residue remains in the film, which does not cause deterioration of film properties such as etching resistance.

[0299] [(C) Thermal acid generator]

[0300] In order to promote the crosslinking reaction by heat, it is preferred to add (C) a thermal acid generator to the metal-containing film-forming composition of the present invention.

[0301] The thermal acid generator (C) that can be used in the metal-containing film-forming composition of the present invention is, for example, represented by the following general formula (7').

[0302] [Chemistry 35]

[0303]

[0304] In the formula, X A - Represents a non-nucleophilic counter ion. 70 , R 71 , R 72 , and R 73 Each represents a hydrogen atom, a linear, branched, or cyclic alkyl group, alkenyl group, oxoalkyl group, or oxoalkenyl group having 1 to 12 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or an aryloxyalkyl group, and some or all of the hydrogen atoms in these groups may be substituted by alkoxy groups or the like. 70 and R 71 , or R 70 , R 71 and R 72 It can also form a ring. When it forms a ring, R 70 and R 71 , or R 70 , R 71 and R 72 It represents an alkylene group having 3 to 10 carbon atoms, or a heteroaromatic ring having a nitrogen atom in the ring.

[0305] The above R 70 , R 71 , R 72 , and R 73 The alkyl groups may be the same as or different from each other. Specifically, examples of the alkyl group include methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, pentyl, hexyl, heptyl, octyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclopropylmethyl, 4-methylcyclohexyl, cyclohexylmethyl, norbornyl and adamantyl.

[0306] Alkenyl groups, such as vinyl, allyl, propenyl, butenyl, hexenyl, cyclohexenyl and the like.

[0307] Oxoalkyl, for example, 2-oxocyclopentyl, 2-oxocyclohexyl, 2-oxopropyl, 2-cyclopentyl-2-oxoethyl, 2-cyclohexyl-2-oxoethyl, 2-(4-methylcyclohexyl)-2-oxoethyl and the like.

[0308] Oxoalkenyl, for example, 2-oxo-4-cyclohexenyl, 2-oxo-4-propenyl, and the like.

[0309] Aryl groups include phenyl, naphthyl, alkoxyphenyl such as p-methoxyphenyl, m-methoxyphenyl, o-methoxyphenyl, ethoxyphenyl, p-tert-butoxyphenyl, m-tert-butoxyphenyl, alkylphenyl such as 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, ethylphenyl, 4-tert-butylphenyl, 4-butylphenyl, dimethylphenyl, alkylnaphthyl such as methylnaphthyl and ethylnaphthyl, alkoxynaphthyl such as methoxynaphthyl and ethoxynaphthyl, dialkylnaphthyl such as dimethylnaphthyl and diethylnaphthyl, and dialkoxynaphthyl such as dimethoxynaphthyl and diethoxynaphthyl.

[0310] Aralkyl groups, such as benzyl, phenylethyl, phenethyl and the like.

[0311] Aryloxoalkyl groups include, for example, 2-aryl-2-oxoethyl groups such as 2-phenyl-2-oxoethyl, 2-(1-naphthyl)-2-oxoethyl and 2-(2-naphthyl)-2-oxoethyl.

[0312] Again, R 70 and R 71 , or R 70 , R 71 and R 72When a heteroaromatic ring having a nitrogen atom in the formula is formed in the ring, for example, imidazole derivatives (for example, imidazole, 4-methylimidazole, 4-methyl-2-phenylimidazole, etc.), pyrazole derivatives, furazol derivatives, pyrroline derivatives (for example, pyrroline, 2-methyl-1-pyrroline, etc.), pyrrolidine derivatives (for example, pyrrolidine, n-methylpyrrolidine, pyrrolidone, N-methylpyrrolidone, etc.), imidazoline derivatives, imidazolinidine derivatives, pyridine derivatives (for example, pyridine, methylpyridine, ethylpyridine, propylpyridine, butylpyridine, 4-(1-butylpentyl)pyridine, dimethylpyridine, trimethylpyridine, triethylpyridine, phenylpyridine, 3-methyl-2-phenylpyridine, 4-tert-butylpyridine, diphenylpyridine, benzylpyridine, methoxypyridine, butoxypyridine, dimethoxypyridine, 4-pyrrolidine

[0063] The invention also includes but is not limited to pyridazine derivatives, pyrimidine derivatives, pyrazine derivatives, pyrazoline derivatives, pyrazolinidine derivatives, piperidine derivatives, piperazine derivatives, morpholine derivatives, indole derivatives, isoindole derivatives, 1H-indazole derivatives, indoleline derivatives, quinoline derivatives (e.g., quinoline, 3-quinolinecarbonitrile, etc.), isoquinoline derivatives, cinnoline derivatives, quinazoline derivatives, quinoxaline derivatives, phthalazine derivatives, purine derivatives, pteridine derivatives, carbazole derivatives, phenanthridine derivatives, acridine derivatives, phenazine derivatives, 1,10-phenanthroline derivatives, adenine derivatives, adenosine derivatives, guanine derivatives, guanosine derivatives, uracil derivatives, urea derivatives, etc.

[0313] As mentioned above, as X A - As for the non-nucleophilic counter ion, examples include halide ions such as chloride ion and bromide ion, fluoroalkyl sulfonates such as trifluoromethanesulfonate, 1,1,1-trifluoroethanesulfonate and nonafluorobutanesulfonate, aryl sulfonates such as toluenesulfonate, benzenesulfonate, 4-fluorobenzenesulfonate and 1,2,3,4,5-pentafluorobenzenesulfonate, alkyl sulfonates such as methanesulfonate and butanesulfonate, imide acids such as bis(trifluoromethylsulfonyl)imide, bis(perfluoroethylsulfonyl)imide and bis(perfluorobutylsulfonyl)imide, methylated acids such as tris(trifluoromethylsulfonyl)methide and tris(perfluoroethylsulfonyl)methide, and further examples include sulfonates substituted with fluorine at the α-position as shown in the following general formula (8) and sulfonates substituted with fluorine at the α- and β-positions as shown in the following general formula (9).

[0314] [Chemistry 36]

[0315]

[0316] In the above general formula (8), R 81is a hydrogen atom, a linear, branched, or cyclic alkyl group having 1 to 23 carbon atoms, an acyl group, an alkenyl group having 2 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aryloxy group. 91 It is a hydrogen atom, a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms.

[0317] Specific examples of the thermal acid generator include the following, but are not limited to these.

[0318] [Chemistry 37]

[0319]

[0320] The (C) thermal acid generator contained in the metal-containing film-forming composition of the present invention can be used alone or in combination of two or more. The amount of the (C) thermal acid generator added is preferably 0.05 to 30 parts by mass, more preferably 0.1 to 10 parts by mass, relative to 100 parts by mass of the above-mentioned (A) metal-containing film-forming compound. If it is 0.05 parts by mass or more, the acid generation amount and cross-linking reaction are sufficient, and if it is 30 parts by mass or less, mixing due to the migration of the acid to the upper resist will not occur.

[0321] [(D) Photoacid generator]

[0322] In order to appropriately adjust the pattern shape, exposure sensitivity, etc. of the resist upper film, a (D) photoacid generator may be added to the metal-containing film-forming composition of the present invention. (D) Photoacid generators may be used alone or in combination of two or more. (D) Photoacid generators may be, for example, those described in paragraphs

[0160] to

[0179] in Japanese Patent Application Publication No. 2009-126940. The amount of the (D) photoacid generator added is preferably 0.05 to 30 parts by mass, and more preferably 0.1 to 10 parts by mass, relative to 100 parts by mass of the above-mentioned (A) metal-containing film-forming compound. If the amount of the photoacid generator added is within the above range, the resolution is good, and there is no problem of foreign matter after the resist is developed or peeled off.

[0323] [(E) Cross-linking agent]

[0324] In addition, in the metal-containing film-forming composition of the present invention, in order to improve the curability and further suppress the cross-mixing with the upper film of the resist, a (E) cross-linking agent may also be added. There is no particular limitation on the (E) cross-linking agent, and various well-known systems of cross-linking agents can be widely used. For example, melamine-based cross-linking agents, glycoluril-based cross-linking agents, benzoguanamine-based cross-linking agents, urea-based cross-linking agents, β-hydroxyalkylamide-based cross-linking agents, isocyanurate-based cross-linking agents, aziridine-based cross-linking agents, oxazoline-based cross-linking agents, epoxy-based cross-linking agents, and phenol-based cross-linking agents. The above-mentioned (E) cross-linking agent can be used alone or in combination of two or more. The addition amount of the (E) cross-linking agent is preferably 5 to 50 parts by mass, and more preferably 10 to 40 parts by mass relative to 100 parts by mass of the above-mentioned (A) metal-containing film-forming compound. If the addition amount is 5 parts by mass or more, sufficient curability can be exhibited and cross-mixing with the upper film of the resist can be suppressed. On the other hand, when the added amount is 50 parts by mass or less, there is no concern that the dry etching resistance may be deteriorated due to a decrease in the ratio of the (A) metal-containing film-forming compound in the composition.

[0325] Specific examples of the melamine-based crosslinking agent include hexamethoxymethylated melamine, hexabutoxymethylated melamine, alkoxy and / or hydroxyl-substituted melamines thereof, and partially self-condensed products thereof.

[0326] Specific examples of the glycoluril-based crosslinking agent include tetramethoxymethyl glycoluril, tetrabutoxymethyl glycoluril, alkoxy and / or hydroxyl-substituted products thereof, and partial self-condensation products thereof.

[0327] Specific examples of the benzoguanamine-based crosslinking agent include tetramethoxymethylated benzoguanamine, tetrabutoxymethylated benzoguanamine, alkoxy and / or hydroxyl-substituted products thereof, and partial self-condensation products thereof.

[0328] Specific examples of the urea crosslinking agent include dimethoxymethylated dimethoxyethylene urea, alkoxy and / or hydroxy substituents thereof, and partial self-condensates thereof.

[0329] Specific examples of the β-hydroxyalkylamide crosslinking agent include N,N,N',N'-tetrakis(2-hydroxyethyl)adipamide.

[0330] Specific examples of the isocyanurate crosslinking agent include triglycidyl isocyanurate and triallyl isocyanurate.

[0331] Specific examples of the aziridine crosslinking agent include 4,4′-bis(ethyleneiminocarbonylamino)diphenylmethane and 2,2-bishydroxymethylbutanol-tris[3-(1-aziridinyl)propionate].

[0332] Oxazoline crosslinking agents include, for example, 2,2'-isopropylidenebis(4-benzyl-2-oxazoline), 2,2'-isopropylidenebis(4-phenyl-2-oxazoline), 2,2'-methylenebis-4,5-diphenyl-2-oxazoline, 2,2'-methylenebis-4-phenyl-2-oxazoline, 2,2'-methylenebis-4-tert-butyl-2-oxazoline, 2,2'-bis(2-oxazoline), 1,3-phenylenebis(2-oxazoline), 1,4-phenylenebis(2-oxazoline), and 2-isopropenyloxazoline copolymers.

[0333] Specific examples of the epoxy crosslinking agent include diglycidyl ether, ethylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,4-cyclohexanedimethanol diglycidyl ether, poly(glycidyl methacrylate), trimethylolethane triglycidyl ether, trimethylolpropane triglycidyl ether, and pentaerythritol tetraglycidyl ether.

[0334] Specific examples of the phenol-based crosslinking agent include compounds represented by the following general formula (10).

[0335] [Chemistry 38]

[0336]

[0337] In the formula, Q is a single bond or a q having 1 to 20 carbon atoms. 1 Valence hydrocarbon group. 16 is a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. 1 It is an integer from 1 to 5.

[0338] Q is a single bond, or a carbon number of 1 to 20 1 Hydroxyl. 1 is an integer of 1 to 5, preferably 2 or 3. Specifically, Q is, for example, methane, ethane, propane, butane, isobutane, pentane, cyclopentane, hexane, cyclohexane, methylpentane, methylcyclohexane, dimethylcyclohexane, trimethylcyclohexane, benzene, toluene, xylene, ethylbenzene, ethylisopropylbenzene, diisopropylbenzene, methylnaphthalene, ethylnaphthalene, eicosane, etc. 1 A group with 10 hydrogen atoms. 16 It is a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. Specifically, the alkyl group having 1 to 20 carbon atoms includes, for example, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, isopentyl, hexyl, octyl, ethylhexyl, decyl, and eicosyl, and a hydrogen atom or a methyl group is preferred.

[0339] Examples of the compound represented by the general formula (10) include the following compounds. Among them, from the viewpoint of improving the hardening property and film thickness uniformity of the metal-containing film, hexamethoxymethylated products of trisphenolmethane, trisphenolethane, 1,1,1-tris(4-hydroxyphenyl)ethane, and tris(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene are preferred.

[0340] [Chemistry 39]

[0341]

[0342] [Chemistry 40]

[0343]

[0344] [(G) Surfactant]

[0345] In the metal-containing film-forming composition of the present invention, in order to improve the coating property of spin coating, a (G) surfactant may be added. (G) Surfactants may be used alone or in combination of two or more. (G) Surfactants, for example, surfactants described in paragraphs

[0142] to

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

[0346] [Plasticizer]

[0347] In addition, a plasticizer may be added to the metal-containing film-forming composition of the present invention. There is no particular limitation on the plasticizer, and plasticizers of various known systems can be widely used. For example, low molecular weight compounds such as phthalates, adipic acid esters, phosphates, trimellitic acid esters, and citrates, polyethers, polyesters, and polymers such as polyacetal polymers recorded in Japanese Patent Publication No. 2013-253227. The amount of the added plasticizer is preferably 1% to 500% by mass relative to 100 parts by mass of the metal-containing film-forming compound (A). If the amount added is within such a range, the pattern is excellent in embedding and planarization.

[0348] <Method for Forming Metal-Containing Film>

[0349] The present invention can form a metal-containing film as, for example, a resist underlayer film of a multilayer resist film used for photolithography using the metal-containing film-forming composition.

[0350] The method for forming a metal-containing film using the metal-containing film-forming composition of the present invention is to apply the above-mentioned metal-containing film-forming composition on the processed substrate by spin coating or the like. After spin coating, the solvent is evaporated, and baking (heat treatment) is performed to prevent mixing with the upper film of the resist and to promote the cross-linking reaction. The baking is preferably performed in the range of 100°C to 450°C for 10 to 600 seconds, and more preferably in the range of 200°C to 300°C for 10 to 300 seconds. Considering the damage to the device and the influence on the deformation of the wafer, the upper limit of the heating temperature of the wafer processing of the lithography is preferably set to be below 450°C, and more preferably below 300°C.

[0351] In addition, in the metal-containing film forming 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 on a processed substrate by the same spin coating method as mentioned above, and the above-mentioned metal-containing film forming composition can be fired in a gas environment with an oxygen concentration of not less than 0.1 volume % and not more than 21 volume % to harden it to form a metal-containing film.

[0352] By firing the metal-containing film-forming composition of the present invention in such an oxygen environment, a fully hardened metal-containing film can be obtained. It is also possible for the gas environment during baking to be in the air. In order to reduce oxygen, pre-sealing inert gases such as N2, Ar, and He will prevent oxidation of the metal-containing film, so it is ideal. In order to prevent oxidation, it is necessary to control the oxygen concentration, preferably below 1,000ppm, and more preferably below 100ppm (volume basis). If oxidation of the metal-containing film during baking is prevented, absorption increase or etching resistance reduction will not occur, so it is ideal.

[0353] Alternatively, the metal-containing film-forming composition can be used to form a metal-containing film as, for example, a resist intermediate film of a multilayer resist film used for photolithography.

[0354] [Pattern Formation Method Using Film-Forming Composition Containing Metal]

[0355] The present invention also provides a pattern forming method, which is a pattern forming method using a two-layer resist process using the metal-containing film-forming composition of the present invention, and is a method for forming a pattern on a processed substrate, comprising the following steps:

[0356] (I-1) After applying the above-mentioned metal-containing film-forming composition on a substrate to be processed, a metal-containing film is formed by heat treatment,

[0357] (I-2) forming a resist upper layer film on the aforementioned metal-containing film using a photoresist material,

[0358] (I-3) after pattern exposure of the resist upper layer film, developing with a developer to form a pattern on the resist upper layer film,

[0359] (I-4) using the patterned resist upper layer film as a mask, transferring the pattern to the metal-containing film by dry etching, and

[0360] (I-5) The metal-containing film to which the pattern has been transferred is used as a mask to process the substrate to form a pattern on the substrate.

[0361] The resist upper film in the above two-layer resist treatment is resistant to etching by chlorine-based gas, so in the above two-layer resist treatment, the dry etching of the metal-containing film using the resist upper film as a mask is preferably performed using an etching gas mainly containing chlorine-based gas. The metal-containing film is resistant to etching by fluorine-based gas, so the dry etching of the processed substrate using the metal-containing film as a mask is preferably performed using an etching gas mainly containing fluorine-based gas.

[0362] The present invention also provides a pattern forming method, as a pattern forming method using a three-layer resist process using the metal-containing film-forming composition of the present invention, which is a method for forming a pattern on a processed substrate, comprising the following steps:

[0363] (II-1) forming a resist underlayer film on a substrate to be processed,

[0364] (II-2) after applying the metal-containing film-forming composition on the resist underlayer film, forming a metal-containing film by heat treatment,

[0365] (II-3) forming a resist upper layer film on the aforementioned metal-containing film using a photoresist material,

[0366] (II-4) after pattern exposure of the resist upper layer film, developing with a developer to form a pattern on the resist upper layer film,

[0367] (II-5) using the patterned resist upper layer film as a mask, transferring the pattern to the metal-containing film by dry etching,

[0368] (II-6) using the metal-containing film to which the pattern has been transferred as a mask, transferring the pattern to the resist underlayer film by dry etching, and

[0369] (II-7) The substrate to be processed is processed using the resist underlayer film to which the pattern has been transferred as a mask to form a pattern on the substrate to be processed.

[0370] The metal-containing film used as the resist intermediate film in the above three-layer resist treatment formed by the metal-containing film-forming composition of the present invention is resistant to etching by oxygen-based gases, so in the above three-layer resist treatment, dry etching of the resist lower film using the metal-containing film as a mask is preferably performed using an etching gas mainly containing oxygen-based gases. The resist lower film is resistant to etching by fluorine-based gases, so dry etching of the substrate to be processed using the resist lower film as a mask is preferably performed using an etching gas mainly containing fluorine-based gases.

[0371] In the above pattern forming method, the resist upper layer film can be either positive or negative, and can use the same photoresist composition as commonly used. When the resist upper layer film is formed using the above photoresist composition, spin coating is preferred.

[0372] When the photoresist composition is used to form the resist upper film by spin coating, the photoresist composition is pre-baked after coating, preferably at 60 to 180° C. and 10 to 300 seconds. After that, exposure is performed according to the usual method, and post-exposure baking (PEB) and development are performed to obtain the resist upper film pattern. In addition, the thickness of the resist upper film is not particularly limited, and 10 to 500 nm, especially 20 to 400 nm is preferred.

[0373] In addition, exposure light, for example, high-energy rays with a wavelength of less than 300nm, specifically, such as far ultraviolet rays, KrF excimer laser (248nm), ArF excimer laser (193nm), F2 laser (157nm), Kr2 laser (146nm), Ar2 laser (126nm), 3-20nm soft X-rays (EUV), electron beams (EB), ion beams, X-rays, etc.

[0374] The patterning method of the resist upper layer film is preferably to form the pattern by optical lithography with a wavelength of 5 nm to 300 nm, direct writing by electron beam, nanoimprinting or a combination thereof.

[0375] Furthermore, the development method of the above-mentioned pattern forming method is preferably alkali development or organic solvent development.

[0376] Then, the obtained resist upper film pattern is used as a mask for etching. For example, the etching of the metal-containing film in the two-layer resist process is carried out by using a chlorine-based gas to use the upper resist pattern as a mask. Thereby, a metal-containing film pattern is formed. Next, the obtained metal-containing film pattern is used as a mask to perform etching processing on the processed substrate. The etching of the processed body can be performed using conventional methods. For example, if the processed body is a SiO2, SiN, or silicon dioxide-based low dielectric constant insulating film, etching using a fluorine-based gas as the main component is performed.

[0377] The metal-containing film obtained from the metal-containing film-forming composition of the present invention has a characteristic of being excellent in etching resistance when etching these workpieces.

[0378] The resist underlayer film material that can be used for the resist underlayer film is, for example, a resist underlayer film material that is well known as an underlayer film for a three-layer resist method or a two-layer resist method using a silicon resist composition. For example, Japanese Patent Application Laid-Open No. 2012-001687, Japanese Patent Application Laid-Open No. 2012-077295, Japanese Patent Application Laid-Open No. 2004-264710, Japanese Patent Application Laid-Open No. 2005-043471, Japanese Patent Application Laid-Open No. 2005-250434, Japanese Patent Application Laid-Open No. 2007-293294, Japanese Patent Application Laid-Open No. 2008-065303, Japanese Patent Application Laid-Open No. 2004-205685, Japanese Patent Application Laid-Open No. 2007-171895, Japanese Patent Application Laid-Open No. 2009-014816, Japanese Patent Application Laid-Open No. 2007-199653, Japanese Patent Application Laid-Open No. 2008-274250, Japanese Patent Application Laid-Open No. 2010-122656, Japanese Patent Application Laid-Open No. 2010-122657, Japanese Patent Application Laid-Open No. 2010-122658, Japanese Patent Application Laid-Open No. 2010-122659 ...9, Japanese Patent Application Laid-Open No. 2010-122659, Japanese Patent Application Laid-Open No. 2010-122659, Japanese Patent Application Laid-Open No. 2010-122659, Japanese Patent Resins and compositions disclosed in JP-A-2012-214720, JP-A-2014-029435, International Publication No. 2012 / 077640, International Publication No. 2010 / 147155, International Publication No. 2012 / 176767, JP-A-2005-128509, JP-A-2006-259249, JP-A-2006-259482, JP-A-2006-293298, JP-A-2007-316282, JP-A-2012-145897, JP-A-2017-119671, JP-A-2019-044022, and the like.

[0379] The resist underlayer film can be formed on the substrate by spin coating, etc., similarly to the photoresist composition, using, for example, a composition solution containing the resist underlayer film material. After the resist underlayer film is formed by spin coating, etc., it is preferably baked to evaporate the organic solvent. The baking temperature is preferably within the range of 100 to 600° C. and the baking time is preferably within the range of 10 to 300 seconds.

[0380] Instead of using the above-mentioned resist underlayer film material, an organic hard mask formed by a CVD method or an ALD method may be used.

[0381] In the case of three-layer resist processing, dry etching of the metal-containing film is performed, for example, using a chlorine-based gas with the upper resist pattern as a mask. This forms a metal-containing film pattern. Next, the obtained metal-containing film pattern is used as a mask, and the resist lower film is etched using an oxygen-based gas. This forms a resist lower film pattern. Next, the obtained resist lower film pattern is used as a mask to perform etching processing on the processed substrate.

[0382] The metal-containing film obtained from the metal-containing film-forming composition of the present invention is characterized by excellent etching resistance when etching these resist underlayer films.

[0383] Furthermore, the object to be processed (substrate to be processed) is not particularly limited, and substrates such as Si, α-Si, p-Si, SiO2, SiN, SiON, W, TiN, Al, etc., and a substrate on which a processed layer is formed, etc. can be used. The processed layer can be various Low-k films such as Si, SiO2, SiON, SiN, p-Si, α-Si, W, W-Si, Al, Cu, Al-Si, and barrier films thereof, and can generally be formed to have a film thickness of 50 to 10,000 nm, particularly 100 to 5,000 nm. Furthermore, when forming the processed layer, the substrate and the processed layer can be made of different materials.

[0384] Here, use Figure 1 The following is an example of a pattern forming method using the three-layer resist process. Figure 1 (A), on the processed layer 2 of the processed substrate composed of the substrate 1 and the processed layer 2 thereon, a resist underlayer film 3 is formed using a resist underlayer film material, a metal-containing film 4 is formed on the resist underlayer film 3 using the metal-containing film-forming composition of the present invention, and a resist upper layer film 5 is formed on the metal-containing film 4 using a photoresist material. Then, as Figure 1 (B), the exposed portion 6 of the resist upper film is subjected to pattern exposure. Figure 1 (C), developing with a developer to form a resist upper film pattern 5a on the resist upper film. Then, as Figure 1 (D), using the resist upper film having formed the resist upper film pattern 5a as a mask, dry etching is used to transfer the pattern to the aforementioned metal-containing film to obtain the metal-containing film pattern 4a. Then, as Figure 1 (E), using the metal-containing film of the transferred pattern 4a as a mask, dry etching is used to transfer the pattern on the resist lower film to obtain the resist lower film pattern 3a. Then, as Figure 1 (F) is to use the resist underlayer film having the pattern 3a formed thereon as a mask to process the processed layer 2 on the substrate 1, thereby forming a pattern 2a on the processed substrate.

[0385] Again, use Figure 2 , an example of a pattern forming method for the above-mentioned two-layer resist processing is described. In this example, first, as Figure 2 (G), a metal-containing film 4 is formed on the processed layer 2 of the processed substrate composed of the substrate 1 and the processed layer 2 thereon using the metal-containing film-forming composition of the present invention, and a resist upper layer film 5 is formed on the metal-containing film 4 using a photoresist material. Then, as Figure 2 (H), the exposed portion 6 of the resist upper film is subjected to pattern exposure. Figure 2 (I) is developed with a developer to form a resist upper film pattern 5a on the resist upper film. Figure 2 (J), the resist upper layer film having formed pattern 5a is used as a mask, and the pattern is transferred to the aforementioned metal-containing film by dry etching to obtain the metal-containing film pattern 4a. Then, as Figure 2 (K), using the metal-containing film having the metal-containing film pattern 4a as a mask, the processed layer 2 on the substrate 1 is processed to form a pattern 2a on the processed substrate.

[0386] [Example]

[0387] The present invention will be described in more detail below with reference to Synthesis Examples, Comparative Synthesis Examples, Examples, and Comparative Examples, but the present invention is not limited thereto.

[0388] [(A) Synthesis of Metal-Containing Film-Forming Compound]

[0389] In the following synthesis examples, the following organic group raw material group G: (G1) to (G10) and silicon-containing organic group raw material group H: (H1) to (H2) were used.

[0390] The organic group raw material group G: (G1) to (G10) and the silicon-containing organic group raw material group H: (H1) to (H2) are shown below.

[0391] [Chemistry 41]

[0392]

[0393] [Chemistry 42]

[0394]

[0395] As the metal source M, the following metal compounds were used.

[0396] (M1): Tetraisopropyltitanium (Sigma-Aldrich Corp, 377996)

[0397] (M2): Hf(OBu)4: n-butoxyhafnium(IV) (Sigma-Aldrich Corp, 667943)

[0398] (M3): Zr(OBu)4: tetrabutoxyzirconium (IV) (80 mass % 1-butanol solution) (Tokyo Chemical Industry Co., Ltd., Z0016)

[0399] [Synthesis Example 1] Synthesis of Metal-Containing Film-Forming Compound (A-1)

[0400] Under nitrogen environment, 28.4 g of tetraisopropyltitanium (M1) was dissolved in 50.0 g of 2-propanol, and a 50.0 g solution of IPA containing 2.7 g of deionized water was added dropwise at room temperature for 2 hours while stirring. 10.0 g of organic group raw material (G1) was added to the obtained solution, and stirred at room temperature for 30 minutes. After the solution was concentrated at 30°C under reduced pressure, it was further heated to 60°C and continued to be heated under reduced pressure until no distillate appeared. At the point when the distillate disappeared, 120.0 g of PGMEA / PGME (mass ratio 70 / 30) solution was added, and heated at 40°C under reduced pressure until IPA no longer distilled, to obtain a PGMEA / PGME solution of a metal-containing film-forming compound (A-1).

[0401] [Synthesis Examples 2 to 8] Synthesis of Metal-Containing Film-Forming Compounds (A-2) to (A-8)

[0402] The metal source M and the organic group raw material group G were used in the feed amounts shown in Table 1, and the same reaction conditions as in Synthesis Example 1 were followed to obtain the metal-containing film-forming compounds (A-2) to (A-8) shown in Table 1.

[0403] [Table 1]

[0404]

[0405] [Synthesis Example 9] Synthesis of Metal-Containing Film-Forming Compound (A-9)

[0406] Under nitrogen environment, 15.0g of tetrabutoxyzirconium (IV) (M3) was dissolved in 20.6g of PGMEA / PGME (mass ratio 70 / 30) solution, and the reaction temperature was raised to 50°C while stirring, and 9.0g of silicon-containing organic group raw material (H1) was added dropwise to the above solution. After the addition, the reaction temperature was set to 60°C and stirring was continued for 2 hours. Then, a mixture of 7.0g of organic group raw material (G3) suspended in 8.6g of PGMEA / PGME (mass ratio 70 / 30) solution was added to the above reaction system, the reaction temperature was maintained at 60°C, and stirring was continued for 1 hour. After cooling to room temperature, the obtained reaction solution was filtered with a 0.45μm PTFE filter to obtain a PGMEA / PGME solution of a metal-containing film-forming compound (A-9).

[0407] [Synthesis Examples 10 to 11, Comparative Synthesis Examples 1 to 2] Synthesis of Metal-Containing Film-Forming Compounds (A-10) to (A-11) and Comparative Example Compounds (R-1) to (R-2)

[0408] The above-mentioned metal source M, the above-mentioned organic group raw material group G and the above-mentioned silicon-containing organic group raw material group H are used in the feed amounts shown in Table 2. Otherwise, the metal-containing film-forming compounds (A-10) to (A-11) and comparative example compounds (R-1) to (R-2) shown in Table 2 are obtained under the same reaction conditions as in Synthesis Example 9.

[0409] [Table 2]

[0410]

[0411] Preparation of Metal-Containing Film-Forming Compositions (MUL1-16, Comparative Examples MUL1-2)

[0412] The metal-containing film-forming composition was prepared by using the metal-containing film-forming compounds (A-1) to (A-11), comparative example compounds (R-1) to (R-2), (AG1) as a thermal acid generator, (AG2) as a photoacid generator, (XL1) to (XL2) as a crosslinking agent, and (F1: ethylene glycol dibenzyl ether: boiling point 364° C.) as a high boiling point solvent. After dissolving in an organic solvent containing 0.001% by mass of PF636 (manufactured by OMNOVA) in the proportions shown in Table 3, the mixture was filtered through a 0.1 μm fluororesin filter to prepare metal-containing film-forming compositions (MUL1 to 16, comparative example MUL1 to 2).

[0413] [Chemistry 43]

[0414]

[0415] [Table 3]

[0416]

[0417] [Evaluation of Solvent Resistance and Contact Angle (Examples 1-1 to 1-16, Comparative Examples 1-1 to 1-2)]

[0418] The metal-containing film-forming composition (MUL-1 to 16, comparative examples MUL-1 to 2) prepared above was coated on a silicon substrate, and after being fired at the temperature shown in Table 4 for 60 seconds, the film thickness from the center to the periphery of the substrate was measured, and the average film thickness (a [nm]) was calculated. Then, PGMEA solvent was dispensed on it, left for 30 seconds and spun dry, and baked at 100°C for 60 seconds to evaporate PGMEA, and the film thickness (b [nm]) was measured. The difference in film thickness before and after PGMEA treatment was calculated (residual film rate: (b / a) × 100).

[0419] Moreover, about each cured film, the contact angle (CA1) with pure water was measured.

[0420] The results are shown in Table 4 below.

[0421] [Table 4]

[0422]

[0423] As shown in Table 4, Examples 1-1 to 1-16 using the metal-containing film-forming composition (MUL-1 to 16) of the present invention all have good film-forming properties, and there is almost no film loss due to solvent treatment, which shows that a film with good solvent resistance is obtained. In addition, by containing any of the groups represented by formulas (a-1) to (a-3), the film has a contact angle of more than 60° to pure water, and it can be expected that good adhesion with the resist pattern can be expected. In particular, it can be seen that Examples 1-12 and 1-15 using a composition containing a thermal acid generator (AG1) have high contact angles. The effect is uncertain, but it is speculated that the hardening caused by the ring-opening reaction of the epoxy or oxetane structure is promoted by the action of the acid generator.

[0424] On the other hand, Comparative Examples 1-1 and 1-2 using compositions other than the metal-containing film-forming composition of the present invention (Comparative Examples MUL-1 and MUL-2) obtained films having good solvent resistance, but the contact angle with pure water was 60° or less.

[0425] [Evaluation of optical constants (n / k) (Examples 2-1 to 2-14, Comparative Examples 1-1 to 1-2)]

[0426] The metal-containing film-forming composition (MUL-3~16, comparison examples MUL-1~2) was coated on a silicon substrate and fired at the temperature shown in Table 5 for 60 seconds. The optical constants (refractive index n, attenuation coefficient k) at a wavelength of 193nm were calculated using a variable incident angle spectroscopic ellipsometer (VASE) manufactured by JA Woollam. The results are shown in Table 5.

[0427] [Table 5]

[0428]

[0429] As shown in Table 5, in Examples 2-1 to 2-14 using the metal-containing film-forming composition (MUL-3 to 16) of the present invention, the n values ​​were all between 1.8 and 2.3, and the k values ​​were all between 0.1 and 0.5.

[0430] The optical constants also depend on the film thickness, the type of resist upper film, etc., but if the n value is between 1.8 and 2.3 and the k value is between 0.1 and 0.5, even when a metal-containing film is formed as a thin film below 20 nm, the reflected light from the substrate under ArF wetting and high NA exposure can be suppressed, and it can be used as a resist lower film for photoresist patterning. In the above embodiments, the optical constants are all within the ideal range, and it can be seen that they are suitable for use as a resist lower film in photoresist patterning.

[0431] [Evaluation of etching resistance (Examples 3-1 to 3-16, Comparative Examples 3-1 to 3-4)]

[0432] The metal-containing film-forming composition (MUL-1 to 16, and comparative examples MUL-1 to 2) was applied on a silicon substrate and heated for 60 seconds at the same temperature as shown in Table 4 using a hot plate to form a metal-containing film (thickness a) with a thickness of 50 nm.

[0433] In Comparative Example 3-3, the following resist interlayer film material containing silicon atoms (SOG-1) was applied and baked at 220° C. for 60 seconds to form a resist interlayer film (film thickness a) having a film thickness of 50 nm.

[0434] A polymer represented by ArF silicon-containing anti-etching intermediate film polymer (SiP1) as an anti-etching intermediate film material (SOG-1) containing silicon atoms, and a thermal cross-linking catalyst (CAT1) are dissolved in a solvent containing 0.1 mass % of FC-4430 (produced by Sumitomo 3M Co., Ltd.) in the proportions shown in Table 6, and filtered with a fluororesin filter with a pore size of 0.1 μm to prepare an anti-etching intermediate film material (SOG-1) containing silicon atoms.

[0435] [Table 6]

[0436]

[0437] The structural formulas of the ArF silicon-containing resist interlayer polymer (SiP1) and the thermal crosslinking catalyst (CAT1) used are shown below.

[0438] [Chemistry 44]

[0439]

[0440] In Comparative Example 3-4, the following organic resist underlayer film material (SOC-1) was applied and baked at 350° C. for 60 seconds to form a resist underlayer film (thickness a) with a film thickness of 50 nm.

[0441] The organic resist underlayer film material (SOC-1) is prepared by dissolving a polymer represented by an organic resist underlayer film polymer (CP1) in a solvent containing 0.1% by mass of FC-4430 (manufactured by Sumitomo 3M Co., Ltd.) in the proportions shown in Table 7, and filtering the solution with a fluororesin filter having a pore size of 0.1 μm to prepare the organic resist underlayer film material (SOC-1).

[0442] [Table 7]

[0443]

[0444] The structural formula of the organic resist underlayer film polymer (CP1) used is shown below.

[0445] [Chemistry 45]

[0446]

[0447] Mw = 7,000, Mw / Mn = 3.50

[0448] Then, using an etching apparatus CE-300I manufactured by ULVAC, etching was performed using CF4 gas and O2 gas under the following conditions, and the film thickness b was measured. The film thickness etched in 1 minute was calculated from the film thickness etched during a specified time using each gas (film thickness a-film thickness b), and the etching rate (nm / min) was defined to determine the etching resistance.

[0449] The etching rate for CF4 gas was rated as "A (very good)" when it was less than 20 nm / min, "B (good)" when it was 20 nm / min to 30 nm / min, and "C (poor)" when it exceeded 30 nm / min.

[0450] Regarding the etching rate for O2 gas, a value of "A (very good)" was given when it was less than 20 nm / min, a value of "B (good)" was given when it was 20 nm / min to 30 nm / min, and a value of "C (poor)" was given when it exceeded 30 nm / min.

[0451] The results are shown in Table 8.

[0452] Dry etching conditions of CF4 gas

[0453] Pressure: 3Pa

[0454] Antenna RF power: 100W

[0455] Bias RF power: 15W

[0456] CF4 gas flow rate: 15sccm

[0457] Time: 30 seconds

[0458] O2 gas dry etching conditions

[0459] Pressure: 3Pa

[0460] Antenna RF power: 300W

[0461] Bias RF power: 10W

[0462] O2 gas flow rate: 25sccm

[0463] Time: 30 seconds

[0464] [Table 8]

[0465]

[0466] As shown in Table 8, Examples 3-1 to 3-16 using the metal-containing film-forming composition (MUL-1 to 16) of the present invention exhibited excellent etching resistance to both CF 4 gas and O 2 gas.

[0467] The metal-containing film-forming composition of the present invention has excellent resistance to etching using CF4 gas compared to SOG-1 used in Comparative Example 3-3, and is therefore suitable for three-layer resist processing in which a resist pattern is transferred to a processed substrate in combination with a resist underlayer film.

[0468] Furthermore, compared with SOC-1 used in Comparative Example 3-4, it has excellent etching resistance to O2 gas and is therefore suitable for a two-layer resist process in which a resist pattern is transferred to a processed substrate in combination with a photoresist upper layer film.

[0469] [Pattern Formation Method (Examples 4-1 to 4-14, Comparative Examples 4-1 to 4-2)]

[0470] As for the resist lower layer film on the substrate, the above-mentioned SOC-1 was used, and it was applied by spin coating on a SiO2 wafer, and baked at 350°C for 60 seconds to produce a carbon film with a thickness of 60nm. The carbon ratio of the carbon film was 46 atomic%, and the optical constant (n / k) at a wavelength of 193nm was 1.42 / 0.50. A composition prepared by diluting a metal-containing film-forming composition (MUL-3~16, and comparative examples MUL-1~2) with an organic solvent (PGMEA / PGME=700 / 300 parts by mass) was applied thereon, and heated for 60 seconds using a hot plate at the same temperature as shown in Table 4 to form a metal-containing film with a thickness of 15nm. An ArF single-layer resist for the resist upper layer film material was applied thereon, and baked at 105°C for 60 seconds to form a photoresist film with a thickness of 100nm. A wet protection film material (TC-1) was applied on the photoresist film and baked at 90° C. for 60 seconds to form a protection film with a film thickness of 50 nm.

[0471] As for the resist upper layer film material (single-layer resist for ArF), a polymer (RP1), an acid generator (PAG1), and a basic compound (Amine1) are dissolved in a solvent containing 0.1 mass % of a surfactant FC-4430 (manufactured by Sumitomo 3M Co., Ltd.) according to the proportions shown in Table 9, and the mixture is filtered through a 0.1 μm fluororesin filter to prepare the material.

[0472] [Table 9]

[0473]

[0474] The polymer (RP1), the acid generator (PAG1), and the basic compound (Amine1) used for the resist upper layer film material (single-layer resist for ArF) are shown below.

[0475] [Chemistry 46]

[0476]

[0477] The wet protective film material (TC-1) was prepared by dissolving the protective film polymer (PP1) in an organic solvent at the ratio shown in Table 10 and filtering the solution with a 0.1 μm fluorine resin filter.

[0478] [Table 10]

[0479]

[0480] The protective film polymer (PP1) used in the wet protective film material (TC-1) is shown below.

[0481] [Chemistry 47]

[0482]

[0483] Then, the film was exposed with an ArF immersion exposure device (manufactured by Nikon Co., Ltd.; NSR-S610C, NA1.30, σ0.98 / 0.78, 35 degree dipole s-polarized illumination, 6% half-step phase shift mask), baked (PEB) at 100°C for 60 seconds, and developed with a 2.38 mass % tetramethylammonium hydroxide (TMAH) aqueous solution for 30 seconds to obtain a 50nm1:1 positive line and space pattern (resist upper film pattern).

[0484] The reflectivity was calculated using PROLITH2020a (LITHO TECH JAPAN Co., Ltd.). The thickness of the metal-containing film was fixed at 10 nm, and the reflectivity of the metal-containing film was calculated when n was 1.60 to 2.20 and k was 0.15 to 0.50. The results are as follows: Figure 3 The optical constant (n / k) that can reduce the reflected light from the base substrate to 1.0% or less during pattern exposure is preferred.

[0485] The pattern cross section was observed using S-4700 (electron microscope manufactured by Hitachi, Ltd.).

[0486] The results are shown in Table 11.

[0487] Next, the metal-containing film is etched by dry etching using the resist upper film pattern as a mask to form a metal-containing film pattern, the resist lower film is etched using the obtained metal-containing film pattern as a mask to form a resist lower film pattern, and the SiO2 film is etched using the obtained resist lower film pattern as a mask. The etching conditions are as follows.

[0488] The pattern cross section was observed using S-4700 (electron microscope manufactured by Hitachi, Ltd.).

[0489] The results are shown in Table 11.

[0490] Conditions for transferring the resist upper layer film pattern to the metal-containing film.

[0491] Dry etching conditions of Cl2 gas

[0492] Pressure: 1Pa

[0493] Antenna RF power: 320W

[0494] Bias RF power: 30W

[0495] Cl2 gas flow rate: 25sccm

[0496] Time: 15 seconds

[0497] Conditions for transferring the metal-containing film pattern to the resist underlayer film.

[0498] O2 gas dry etching conditions

[0499] Pressure: 1Pa

[0500] Antenna RF power: 300W

[0501] Bias RF power: 10W

[0502] O2 gas flow rate: 25sccm

[0503] Time: 20 seconds

[0504] Conditions for transferring the resist underlayer film pattern to the SiO2 film.

[0505] Dry etching conditions of CF4 gas

[0506] Pressure: 1Pa

[0507] Antenna RF power: 100W

[0508] Bias RF power: 15W

[0509] CF4 gas flow rate: 15sccm

[0510] Time: 60 seconds

[0511] [Table 11]

[0512]

[0513] As shown in Table 11, it can be confirmed that Examples 4-1 to 4-14 using the metal-containing film-forming composition (MUL-3 to 16) of the present invention all have good pattern shapes after development. The metal-containing film-forming composition of the present invention contains a metal-containing film-forming compound containing any of the groups represented by formulas (a-1) to (a-3), has high adhesion to the resist pattern, and has an optical constant that can sufficiently reduce the substrate reflected light during pattern exposure, so it is estimated that a good resist pattern can be obtained. In addition, after the substrate is transferred and etched, the resist upper film pattern is finally well transferred to the substrate, and it can be confirmed that it is suitable for use in micro-processing using a multilayer resist method.

[0514] In contrast, in Comparative Examples MUL-1 and 2 and Comparative Examples 4-1 and 4-2, which were evaluated as having low contact angles, collapse of the resist upper layer film pattern was observed after development.

[0515] From the above, the metal-containing film-forming compound, the composition using the compound, and the pattern forming method using the composition of the present invention have high adhesion with the resist upper film pattern and have the effect of suppressing the collapse of the fine pattern, and can give the resist upper film a pattern shape with high rectangularity. Therefore, it is particularly suitable for use in multilayer resist processing and is extremely useful for fine patterning for semiconductor device manufacturing.

[0516] This description includes the following aspects.

[0517] [1]: A metal-containing compound for film formation, characterized in that:

[0518] The metal-containing film-forming compound contains at least one metal atom selected from the group consisting of Ti, Zr, and Hf and a ligand coordinated to the metal atom, wherein the ligand contains any of the groups represented by the following formulae (a-1) to (a-3):

[0519] [Chemistry 48]

[0520]

[0521] In the formula, R1 is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and * represents a bonding portion.

[0522] [2]: The metal-containing film-forming compound according to [1], wherein the ligand is derived from a structure represented by the following general formula (1) or (2):

[0523] R a XOH(1)

[0524] R a XCOOH(2)

[0525] In the formula, R a It is any of the groups represented by the above formulae (a-1) to (a-3), and X is a divalent organic group having 1 to 20 carbon atoms.

[0526] [3]: The metal-containing film-forming compound according to [2], wherein

[0527] The aforementioned X is a hydrocarbon group having 1 to 10 carbon atoms, or the structure represented by the aforementioned general formula (2) is a structure represented by the following general formula (x-1) or (x-2), or the structure represented by the aforementioned general formula (1) is a structure represented by the following formula (x-3),

[0528] [Chemistry 49]

[0529]

[0530] In the formula, Y1 to Y3 are divalent organic groups having 1 to 10 carbon atoms, and R aAs before, n is 0 or 1, m is 0 or 1,

[0531] [Chemistry 50]

[0532]

[0533] In the formula, Y4 is a divalent organic group having 1 to 10 carbon atoms, R a As mentioned above, l is 0 or 1.

[0534] [4]: The metal-containing film-forming compound according to [3], wherein Y1 to Y4 are divalent hydrocarbon groups having 1 to 10 carbon atoms.

[0535] [5]: A metal-containing film-forming compound as described in any one of [2] to [4], wherein the metal-containing film-forming compound is a reaction product of a metal compound represented by the following general formula (3), or a metal-containing compound containing any of a hydrolyzate, a condensate, or a hydrolysis-condensate of the metal compound represented by the following general formula (3), and a structure represented by the above general formula (1) or (2),

[0536] [Chemistry 51]

[0537] L a MX b (3)

[0538] In the formula, M is any one of Ti, Zr, and Hf. L is a monodentate ligand or a polydentate ligand having 1 to 30 carbon atoms, and X is selected from a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, and -NR 1 R 2 The hydrolyzable group in 1 and R 2 Each independently represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. a+b=4, and a and b are integers of 0-4.

[0539] [6]: The metal-containing film-forming compound according to [5], wherein the metal compound has a structure represented by the following general formula (4):

[0540] M(OR 1A )4 (4)

[0541] In the formula, M is the same as above, R 1A It is a monovalent organic group having 1 to 20 carbon atoms.

[0542] [7]: The metal-containing film-forming compound according to any one of [1] to [6], wherein the metal-containing film-forming compound further contains a ligand derived from a silicon compound represented by the following general formula (5):

[0543] [Chemistry 52]

[0544]

[0545] In the formula, R 3A , R 3B and R 3C is any organic group having 2 to 30 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and an aryl group having 6 to 20 carbon atoms, which is a crosslinking group having any of the structures represented by the following general formulae (b-1) to (b-3),

[0546] [Chemistry 53]

[0547]

[0548] In the formula, R3 is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, q is 0 or 1, and * represents a bonding portion.

[0549] [8]: A metal-containing film-forming composition comprising (A) a metal-containing film-forming compound as described in any one of [1] to [7], and (B) an organic solvent.

[0550] [9]: The metal-containing film-forming composition according to [8], wherein the metal-containing film-forming composition contains one or more of (C) a thermal acid generator and (D) a photoacid generator.

[0551]

[10] : The metal-containing film-forming composition according to [8] or [9], wherein the metal-containing film-forming composition further contains one or more of (E) a cross-linking agent and (G) a surfactant.

[0552]

[11] : The metal-containing film-forming composition according to any one of [8] to

[10] above, wherein

[0553] 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.

[0554]

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

[0555] (I-1) After applying the metal-containing film-forming composition as described in any one of [8] to

[11] on a substrate to be processed, forming a metal-containing film by heat treatment,

[0556] (I-2) forming a resist upper layer film on the aforementioned metal-containing film using a photoresist material,

[0557] (I-3) after pattern exposure of the resist upper layer film, developing with a developer to form a pattern on the resist upper layer film,

[0558] (I-4) using the patterned resist upper layer film as a mask, transferring the pattern to the metal-containing film by dry etching, and

[0559] (I-5) The metal-containing film to which the pattern has been transferred is used as a mask to process the substrate to form a pattern on the substrate.

[0560]

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

[0561] (II-1) forming a resist underlayer film on a substrate to be processed,

[0562] (II-2) coating the metal-containing film-forming composition as described in any one of [8] to

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

[0563] (II-3) forming a resist upper layer film on the aforementioned metal-containing film using a photoresist material,

[0564] (II-4) after pattern exposure of the resist upper layer film, developing with a developer to form a pattern on the resist upper layer film,

[0565] (II-5) using the patterned resist upper layer film as a mask, transferring the pattern to the metal-containing film by dry etching,

[0566] (II-6) using the metal-containing film to which the pattern has been transferred as a mask, transferring the pattern to the resist underlayer film by dry etching, and

[0567] (II-7) The substrate to be processed is processed using the resist underlayer film to which the pattern has been transferred as a mask to form a pattern on the substrate to be processed.

[0568]

[14] : A method for producing a metal-containing film-forming compound, characterized by:

[0569] A metal compound containing at least one metal atom selected from the group consisting of Ti, Zr, and Hf and a ligand containing any of the groups represented by the following formulae (a-1) to (a-3) are reacted.

[0570] [Chemistry 54]

[0571]

[0572] In the formula, R1 is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and * represents a bonding portion.

[0573]

[15] : A method for producing a metal-containing film-forming compound according to

[14] , wherein the ligand used is a ligand having a structure represented by the following general formula (1) or (2):

[0574] R a XOH(1)

[0575] R a XCOOH(2)

[0576] In the formula, R a It is any of the groups represented by the above formulae (a-1) to (a-3), and X is a divalent organic group having 1 to 20 carbon atoms.

[0577]

[16] : A method for producing a metal-containing film-forming compound according to

[15] , wherein:

[0578] The ligand used is a ligand in which the aforementioned X is a hydrocarbon group having 1 to 10 carbon atoms, or the structure represented by the aforementioned general formula (2) is a structure represented by the following general formula (x-1) or (x-2), or the structure represented by the aforementioned general formula (1) is a structure represented by the following formula (x-3),

[0579] [Chemistry 55]

[0580]

[0581] In the formula, Y1 to Y3 are divalent organic groups having 1 to 10 carbon atoms, and R a As mentioned above, n is 0 or 1, and m is 0 or 1.

[0582] [Chemistry 56]

[0583]

[0584] In the formula, Y4 is a divalent organic group having 1 to 10 carbon atoms, R a As mentioned above, l is 0 or 1.

[0585]

[17] : The method for producing a metal-containing film-forming compound according to

[16] , wherein Y1 to Y4 are divalent hydrocarbon groups having 1 to 10 carbon atoms.

[0586]

[18] : The method for producing a metal-containing film-forming compound according to any one of

[15] to

[17] , wherein:

[0587] The metal-containing film-forming compound is a reaction product of a metal compound represented by the following general formula (3), or a metal-containing compound containing any of a hydrolyzate, a condensate, or a hydrolysis-condensate of the metal compound represented by the following general formula (3), and a structure represented by the above general formula (1) or (2).

[0588] [Chemistry 57]

[0589] L a MX b (3)

[0590] In the formula, M is any one of Ti, Zr, and Hf. L is a monodentate ligand or a polydentate ligand having 1 to 30 carbon atoms, and X is selected from a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, and -NR 1 R 2 The hydrolyzable group in R 1 and R 2 Each independently represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. a+b=4, and a and b are integers of 0-4.

[0591]

[19] : The method for producing a metal-containing film-forming compound according to

[18] , wherein the metal compound has a structure represented by the following general formula (4):

[0592] M(OR 1A )4(4)

[0593] In the formula, M is the same as above, R 1A It is a monovalent organic group having 1 to 20 carbon atoms.

[0594] The present invention is not limited to the above-mentioned embodiments. The above-mentioned embodiments are illustrative only, and any device having substantially the same configuration and exhibiting the same function and effect as the technical concept described in the claims of the present invention is included in the technical scope of the present invention.

[0595] Description of Reference Numerals

[0596] 1: Processed substrate

[0597] 2: Processing layer

[0598] 2a: Pattern (pattern formed on the processed layer)

[0599] 3: Resist lower layer film

[0600] 3a: Resist lower film pattern

[0601] 4: Metal-containing films

[0602] 4a: Metal-containing film pattern

[0603] 5: Resist upper film

[0604] 5a: Resist upper film pattern

[0605] 6: Exposure part

Claims

1. A metal-containing film-forming compound, characterized in that: The metal-containing film-forming compound contains at least one metal atom selected from the group consisting of Ti, Zr, and Hf and a ligand coordinated to the metal atom, wherein the ligand contains any of the groups represented by the following formulae (a-1) to (a-3), In the formula, R1 is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and * represents a bonding portion.

2. The metal-containing film-forming compound according to claim 1, wherein The ligand is derived from a structure represented by the following general formula (1) or (2): R a XOH(1) R a XCOOH(2) In the formula, R a It is any of the groups represented by the formulae (a-1) to (a-3), and X is a divalent organic group having 1 to 20 carbon atoms.

3. The metal-containing film-forming compound according to claim 2, wherein The X is a hydrocarbon group having 1 to 10 carbon atoms, or the structure represented by the general formula (2) is a structure represented by the following general formula (x-1) or (x-2), or the structure represented by the general formula (1) is a structure represented by the following formula (x-3), In the formula, Y1 to Y3 are divalent organic groups having 1 to 10 carbon atoms, and R a As before, n is 0 or 1, m is 0 or 1, In the formula, Y4 is a divalent organic group having 1 to 10 carbon atoms, R a As mentioned above, l is 0 or 1.

4. The metal-containing film-forming compound according to claim 3, wherein The Y1 to Y4 are divalent hydrocarbon groups having 1 to 10 carbon atoms.

5. The metal-containing film-forming compound according to claim 2, wherein The metal-containing film-forming compound is a reaction product of a metal compound represented by the following general formula (3), or a metal-containing compound containing any of a hydrolyzate, a condensate, or a hydrolysis-condensate of the metal compound represented by the following general formula (3), and a structure represented by the above general formula (1) or (2). -aMX(3) In the formula, M is any one of Ti, Zr, and Hf, L is a monodentate ligand or a polydentate ligand having 1 to 30 carbon atoms, and X is selected from a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, and -NR 1 R 2 The hydrolyzable group in 1 and R 2 Each independently represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; a+b=4, and a and b are integers of 0-4.

6. The metal-containing film-forming compound according to claim 5, wherein The metal compound has a structure represented by the following general formula (4): M(OR 1A )4(4) In the formula, M is the same as above, R 1A It is a monovalent organic group having 1 to 20 carbon atoms.

7. The metal-containing film-forming compound according to claim 1, wherein The metal-containing film-forming compound further contains a ligand derived from a silicon compound represented by the following general formula (5): In the formula, R 3A , R 3B and R 3C , is any organic group selected from a crosslinking group having a structure represented by any of the following general formulae (b-1) to (b-3) having 2 to 30 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and an aryl group having 6 to 20 carbon atoms, In the formula, R3 is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, q is 0 or 1, and * represents a bonding portion.

8. A metal-containing film-forming composition, characterized in that Contains (A) the metal-containing film-forming compound according to any one of claims 1 to 7, and (B) an organic solvent.

9. The metal-containing film-forming composition according to claim 8, wherein The metal-containing film-forming composition contains one or more of (C) a thermal acid generator and (D) a photoacid generator.

10. The metal-containing film-forming composition according to claim 8, wherein The metal-containing film-forming composition further contains one or more of (E) a cross-linking agent and (G) a surfactant.

11. The metal-containing film-forming composition according to claim 8, wherein 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.

12. A method for forming a pattern on a processed substrate, characterized by comprising the following steps: (I-1) After applying the metal-containing film-forming composition according to claim 8 onto a substrate to be processed, a metal-containing film is formed by heat treatment, (I-2) forming a resist upper layer film on the metal-containing film using a photoresist material, (I-3) after pattern exposure of the resist upper layer film, developing with a developer to form a pattern on the resist upper layer film, (I-4) using the patterned resist upper layer film as a mask, transferring the pattern to the metal-containing film by dry etching, and (I-5) The metal-containing film to which the pattern has been transferred is used as a mask to process the substrate to form a pattern on the substrate.

13. A method for forming a pattern on a processed substrate, The method is characterized by having the following steps: (II-1) forming a resist underlayer film on a substrate to be processed, (II-2) Coating on the resist underlayer film After the metal-containing film-forming composition according to claim 8 is prepared, a metal-containing film is formed by heat treatment, (II-3) forming a resist upper layer film on the metal-containing film using a photoresist material, (II-4) after pattern exposure of the resist upper layer film, developing with a developer to form a pattern on the resist upper layer film, (II-5) using the patterned resist upper layer film as a mask, transferring the pattern to the metal-containing film by dry etching, (II-6) using the metal-containing film to which the pattern has been transferred as a mask, transferring the pattern to the resist underlayer film by dry etching, and (II-7) The substrate to be processed is processed using the resist underlayer film to which the pattern has been transferred as a mask to form a pattern on the substrate to be processed.

14. A method for producing a metal-containing film-forming compound, characterized by: A metal compound containing at least one metal atom selected from the group consisting of Ti, Zr, and Hf and a ligand containing any of the groups represented by the following formulae (a-1) to (a-3) are reacted. In the formula, R1 is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and * represents a bonding portion.

15. The method for producing a metal-containing film-forming compound according to claim 14, wherein: The ligand used may have a structure represented by the following general formula (1) or (2): R a XOH(1) R a XCOOH(2) In the formula, R a It is any of the groups represented by the formulae (a-1) to (a-3), and X is a divalent organic group having 1 to 20 carbon atoms.

16. The method for producing a metal-containing film-forming compound according to claim 15, wherein: The ligand, wherein X is a hydrocarbon group having 1 to 10 carbon atoms, or the structure represented by the general formula (2) is a structure represented by the following general formula (x-1) or (x-2), or the structure represented by the general formula (1) is a structure represented by the following formula (x-3), In the formula, Y1 to Y3 are divalent organic groups having 1 to 10 carbon atoms, and R a As before, n is 0 or 1, m is 0 or 1, In the formula, Y4 is a divalent organic group having 1 to 10 carbon atoms, R a As mentioned above, l is 0 or 1.

17. The method for producing a metal-containing film-forming compound according to claim 16, wherein Y1 to Y4 are divalent hydrocarbon groups having 1 to 10 carbon atoms.

18. The method for producing a metal-containing film-forming compound according to any one of claims 15 to 17, wherein: The metal-containing film-forming compound is a reaction product of a metal compound represented by the following general formula (3), or a metal-containing compound containing any of a hydrolyzate, a condensate, or a hydrolysis-condensate of the metal compound represented by the following general formula (3), and a structure represented by the above general formula (1) or (2). LaMX(3) In the formula, M is any one of Ti, Zr, and Hf, L is a monodentate ligand or a polydentate ligand having 1 to 30 carbon atoms, and X is selected from a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, and -NR 1 R 2 The hydrolyzable group in 1 and R 2 Each independently represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; a+b=4, and a and b are integers of 0-4.

19. The method for producing a metal-containing film-forming compound according to claim 18, wherein: The metal compound used is a compound having a structure represented by the following general formula (4): M(OR 1A )4(4) In the formula, M is the same as above, R 1A It is a monovalent organic group having 1 to 20 carbon atoms.

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