Composition for forming metal-containing film and method for forming pattern

Abstract

To provide a composition for forming a metal-containing film, having superior dry etching resistance compared to conventional organic underlayer film materials, and also having high filling and planarizing properties, as well as a method for forming a pattern using the composition.SOLUTION: The present invention relates to a composition for forming a metal-containing film, the composition containing: (A) a metal compound containing at least one metal selected from the group consisting of Ti, Zr, and Hf; (B) a crosslinking agent containing, per molecule, 2 or more and 4 or fewer cyclic ether structures having 2 to 13 carbon atoms; and (C) a solvent.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] As LSIs become more highly integrated and faster, pattern dimensions are becoming finer. Lithography technology has achieved the formation of finer patterns by shortening the wavelength of light sources and selecting appropriate resist compositions to match them, in line with this trend. The core of this technology is a positive photoresist composition used in a single layer. This single-layer positive photoresist composition has a skeleton in the resist resin that is resistant to dry etching using chlorine- or fluorine-based gas plasma, and also has a switching mechanism that dissolves the exposed areas, forming a pattern by dissolving the exposed areas, and then dry etching the substrate using the remaining resist pattern as an etching mask.

[0003] However, when the thickness of the photoresist film used is made finer, that is, when the pattern width is made smaller, the resolution performance of the photoresist film is reduced, and when an attempt is made to develop the photoresist film into a pattern using a developer, the so-called aspect ratio becomes too large, resulting in problems such as pattern collapse. For this reason, photoresist films have been made thinner as patterns become finer.

[0004] On the other hand, in the processing of a substrate to be processed, a method is usually used in which a photoresist film on which a pattern is formed is used as an etching mask to process the substrate by dry etching, but in reality, there is no dry etching method that can obtain perfect etching selectivity between the photoresist film and the substrate to be processed. Therefore, there is a problem that the photoresist film is also damaged and collapsed during processing of the substrate, and the resist pattern cannot be accurately transferred to the substrate to be processed. Therefore, with the miniaturization of patterns, a higher dry etching resistance has been required for the resist composition. However, on the other hand, in order to increase the resolution, a resin with low light absorption at the exposure wavelength has been required for the resin used in the photoresist composition. Therefore, as the exposure light has become shorter in wavelength from i-line to KrF and ArF, the resin has also changed to novolac resin, polyhydroxystyrene, and resin with an aliphatic polycyclic skeleton, but in reality, the etching speed under dry etching conditions during substrate processing has become faster, and recent photoresist compositions with high resolution tend to have weaker etching resistance.

[0005] For this reason, it has become necessary to dry etch the substrate to be processed using a thinner photoresist film with a weaker etching resistance, and securing the materials and processes for this processing step has become an urgent need.

[0006] One method for solving such problems is the multi-layer resist method, in which a resist intermediate film having etching selectivity different from that of a photoresist film (i.e., a resist upper layer film) is interposed between the resist upper layer film and a substrate to be processed, a pattern is obtained in the resist upper layer film, and then the pattern is transferred to the resist intermediate film by dry etching using the resist upper layer film pattern as a dry etching mask, and the pattern is further transferred to the substrate to be processed by dry etching using the resist intermediate film as a dry etching mask.

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

[0008] On the other hand, in recent years, the miniaturization of DRAM memory has accelerated, and the need for a resist underlayer film having further improved dry etching resistance and excellent filling and planarization properties has increased. As a coating-type resist underlayer film (organic film) material having excellent filling and planarization properties, for example, the one described in Patent Document 2 has been reported, but in terms of application to the latest generation, there are concerns about dry etching resistance, and the application limit of conventional coating-type resist underlayer film materials is approaching.

[0009] In response to the above-mentioned problems, development of a resist underlayer film using a material containing a metal element is being considered. In Patent Document 3, a material using a Ti compound is 3 / CF 4 Gases and CO2 / N 2 It has been reported that the film shows excellent dry etching resistance against SiO2-based gases.

[0010] On the other hand, one of the problems when using metal compounds for resist underlayer films is embeddability. Although Patent Document 3 does not mention embeddability, metal oxide compounds generally have large thermal shrinkage during baking, and induce significant deterioration of filling properties after high-temperature baking, so there is a concern that they are insufficient as resist underlayer film materials that require high-level planarization properties, embedding properties, and heat resistance properties. Patent Documents 4 and 5 report that metal compounds modified with specific ligands have excellent embeddability, but the bake temperature for the embeddability evaluation that was carried out is as low as 150° C., and there is a concern that they are insufficient as resist underlayer films that require heat resistance (for example, properties against heat treatment that may be performed after the formation of the resist underlayer film). [Prior art documents] [Patent documents]

[0011] [Patent Document 1] JP 2004-205685 A [Patent Document 2] Patent No. 6714493 [Patent Document 3] Patent No. 6189758 [Patent Document 4] Patent No. 6786391 [Patent Document 5] Patent No. 7050137 Summary of the Invention [Problem to be solved by the invention]

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

[0013] In order to solve the above problems, the present invention provides (A) a metal compound containing at least one metal selected from the group consisting of Ti, Zr, and Hf; (B) a crosslinking agent containing 2 to 4 cyclic ether structures having 2 to 13 carbon atoms in the molecule; (C) a solvent; The present invention provides a composition for forming a metal-containing film, which comprises:

[0014] With such a composition for forming a metal-containing film, the reaction between the metal compound and the crosslinking agent can suppress thermal shrinkage of the metal compound during baking, making it possible to provide a metal-containing film (resist underlayer film) with excellent embedding properties.

[0015] The (B) crosslinking agent preferably has two or more epoxy groups or oxetanyl groups in the molecule.

[0016] Such a crosslinking agent has improved reactivity with metal compounds, making it possible to provide a resist underlayer film with better embedding ability.

[0017] The (B) crosslinking agent is preferably any of the organic compounds represented by the following formula (1). [ka] (In the above formula (1), X is an m-valent organic group having 1 to 50 carbon atoms, L is a carbonyl group or a divalent organic group having 1 to 10 carbon atoms, and R 1 and R 2 are each independently a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms; R 1a is an alicyclic hydrocarbon group having 3 to 10 carbon atoms, l represents 0 or 1, and m represents 2 to 4.

[0018] Such a crosslinking agent has improved reactivity with the metal compound, making it possible to provide a resist underlayer film with even better embedding ability.

[0019] In the formula (1), X is preferably an m-valent organic group containing at least one of a quaternary carbon atom, an aromatic ring, an alicyclic hydrocarbon, or a heterocycle.

[0020] Such a crosslinking agent has excellent heat resistance, and therefore the reaction with the metal compound is accelerated during baking, and the embedding property of the metal-containing film-forming composition can be further improved.

[0021] In the formula (1), X preferably has any one of the following structures: [ka] (In the above formula, n is 1 to 5, r is 0 or 1, s is 1 or 2, and R 3 , R 4 are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms which may contain a halogen atom, R 5 is a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 10 carbon atoms, and R 6 , R 7 are each independently a hydrogen atom, a hydroxyl group, or an organic group containing an alkyl group, an alkylene group, or an alkynyl group having 1 to 10 carbon atoms; R 8 is a hydrogen atom, a hydroxyl group, or an organic group containing an alkyl group, alkylene group, or alkynyl group having 1 to 10 carbon atoms, and * represents the bonding site with L. The carbon atom in the aromatic ring of the above formula may have a hydroxyl group, a carboxyl group, an ethenyl group, an ethynyl group, an amino group, a sulfide group, or an alkyl group having 1 to 10 carbon atoms which may contain any of these as a substituent.

[0022] Such a crosslinking agent has excellent thermal fluidity and heat resistance, and can further improve the embedding property of the metal-containing film-forming composition.

[0023] The (A) metal compound is preferably derived from a metal compound represented by the following formula (2). [ka] (In the formula, M is any one of Ti, Zr, and Hf. Ln is independently a monodentate or polydentate ligand having 1 to 30 carbon atoms, and Xn is independently a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, -NR a R b R is a hydrolyzable group selected from the group consisting of a and R b are each independently a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; a+b=4, and a and b are integers of 0 to 4.

[0024] By using such a metal compound, it is possible to form a composition for forming a metal-containing film that exhibits excellent resistance to dry etching using oxygen gas and fluorine gas.

[0025] The formula (2) is preferably a structure of the following formula (3). [ka] (Wherein, M is Ti, Zr, or Hf; R 1A is a monovalent organic group having 1 to 20 carbon atoms.

[0026] A metal compound having such a structure is preferable from the viewpoints of productivity and availability of raw materials.

[0027] The (A) metal compound is preferably a reaction product of a compound derived from the metal compound represented by the formula (2) and an organic compound having 1 to 30 carbon atoms and containing at least one crosslinking group represented by the following general formulae (a-1) to (a-4), (b-1) to (b-4), (c-1) to (c-3), and (d-1) to (d-2). [ka] (In the above general formulas (a-1) to (a-4), R aare independently a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, q represents 0 or 1, and * represents a bond. [ka] (In the above general formula, R b are independently a hydrogen atom or a methyl group, which may be the same or different in the same formula; R c is hydrogen, or a substituted or unsubstituted, saturated or unsaturated monovalent organic group having 1 to 20 carbon atoms, a substituted or unsubstituted, aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted, arylalkyl group having 7 to 31 carbon atoms, and * represents a bonding site. [ka] (In the above general formulas (c-1) to (c-3), Y 1 are independently a divalent organic group having 1 to 20 carbon atoms, R is a hydrogen atom, a substituted or unsubstituted saturated monovalent organic group having 1 to 20 carbon atoms or an unsaturated monovalent 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 d are independently an organic group represented by the following general formula (c-4) which generates one or more hydroxyl groups or carboxyl groups by the action of either or both of an acid and heat, and * represents a bond. [ka] (In the above general formula (c-4), R e is an organic group whose protecting group is removed by the action of either acid or heat, or both, and * is Y 1 ) [ka] (In the formula, R f is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and * indicates a bond.

[0028] The inclusion of such a crosslinking group improves the reactivity with the crosslinking agent, and the volume shrinkage during baking can be further reduced, so that a metal-containing film-forming composition having excellent planarization and filling properties can be provided even after high-temperature baking.

[0029] The amount of the (B) crosslinking agent added is preferably 5 to 100 parts by mass per 100 parts by mass of the (A) metal compound.

[0030] Such an amount of addition can provide a metal-containing film that has excellent embedding properties for uneven substrates and produces a small amount of outgassing during baking.

[0031] The (C) solvent is preferably a mixture of one or more organic solvents having a boiling point of less than 180°C and one or more organic solvents having a boiling point of 180°C or higher.

[0032] By including such a high boiling point solvent, it is possible to suppress the self-crosslinking of the metal compound that causes the generation of voids, and the solvent that coexists during film formation contributes to improving the thermal fluidity of the metal-containing film-forming composition and reducing defects caused by drying, so that a suitable metal-containing film can be formed. Note that in this specification, the boiling point is the value at 1 atmosphere (1013 hPa).

[0033] The present invention also provides a method for forming a pattern on a workpiece substrate, comprising the steps of: (I-1) a step of applying the composition for forming a metal-containing film onto a substrate to be processed and then heat-treating the composition to form a metal-containing film; (I-2) forming a resist top layer film on the metal-containing film using a photoresist material; (I-3) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (I-4) a step of transferring the pattern to the metal-containing film by dry etching using the resist top layer film on which the pattern is formed as a mask; and (I-5) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. The present invention provides a pattern forming method comprising the steps of:

[0034] By the pattern formation method using the two-layer resist process, a fine pattern can be formed on a workpiece (substrate).

[0035] The present invention also provides a method for forming a pattern on a workpiece substrate, comprising the steps of: (II-1) forming a resist underlayer film on a substrate to be processed; (II-2) a step of applying the above-mentioned composition for forming a metal-containing film onto the resist underlayer film, and then performing a heat treatment to form a metal-containing film; (II-3) forming a resist top layer film on the metal-containing film using a photoresist material; (II-4) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (II-5) a step of transferring the pattern to the metal-containing film by dry etching using the resist upper layer film on which the pattern is formed as a mask; (II-6) a step of transferring a pattern to the resist underlayer film by dry etching using the metal-containing film to which the pattern has been transferred as a mask; (II-7) a step of processing the substrate using the resist underlayer film on which the pattern is formed as a mask to form a pattern on the substrate; The present invention provides a pattern forming method comprising the steps of:

[0036] The pattern formation method using the three-layer resist process described above makes it possible to form fine patterns on a workpiece with high precision.

[0037] As described above, in the present invention, the composition for forming a metal-containing film may be used to directly form a metal-containing film on a substrate to be processed as a resist underlayer film, or a resist underlayer film may be formed on the substrate to be processed and then a metal-containing film may be formed separately.

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

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

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

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

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

[0043] When the inorganic hard mask is formed by a CVD method or an ALD method, a fine pattern can be formed on a workpiece with higher accuracy.

[0044] The present invention also provides a method for forming a pattern on a workpiece substrate, comprising the steps of: (V-1) a step of applying the composition for forming a metal-containing film onto a substrate to be processed and then heat-treating the composition to form a metal-containing film; (V-2) forming an organic intermediate film on the metal-containing film; (V-3) forming a silicon-containing resist intermediate film or a combination of an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film and an organic thin film on the organic intermediate film; (V-4) forming a resist top layer film on the silicon-containing resist intermediate film or the organic thin film using a photoresist material; (V-5) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (V-6) a step of transferring a pattern to the silicon-containing resist intermediate film or the organic thin film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (V-7) a step of transferring a pattern to an organic intermediate film by dry etching using the silicon-containing resist intermediate film or the inorganic hard mask intermediate film to which the pattern has been transferred as a mask; (V-8) a step of transferring a pattern to the metal-containing film by dry etching using the organic intermediate film as a mask; and (V-9) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. The present invention provides a pattern forming method comprising the steps of:

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

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

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

[0048] As described above, the metal-containing film-forming composition of the present invention is composed of (A) a metal compound, (B) a crosslinking agent containing 2 to 4 cyclic ether structures having 2 to 10 carbon atoms in the molecule, and (C) a solvent. The reaction between (A) the metal compound and (B) the crosslinking agent can alleviate the volumetric shrinkage of the metal compound, which is a cause of voids, and therefore a resist underlayer film material having excellent planarization properties / filling properties can be provided even after high-temperature baking.

[0049] In particular, in fine patterning processes using multi-layer resist methods in semiconductor device manufacturing processes, it is possible to fill without causing defects such as voids or peeling, even on substrates having areas that are difficult to fill / planarize, such as dense areas of high aspect ratio fine pattern structures such as those in DRAM memories, which are becoming increasingly miniaturized.In addition, since it has superior dry etching resistance compared to conventional coating-type resist underlayer film materials, it is possible to form fine patterns on the workpiece with even greater precision than with resist underlayer films. [Brief description of the drawings]

[0050] [Figure 1] FIG. 1 is an explanatory diagram of an example of the pattern forming method of the present invention (three-layer resist process). [Diagram 2] FIG. 2 is an explanatory diagram of an example of the tone reversal patterning method of the present invention (reversal of the SOC pattern in a three-layer resist process). [Diagram 3] FIG. 3 is an explanatory diagram of a method for evaluating embedding characteristics. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0051] As described above, in a fine patterning process using a multilayer resist method, there has been a demand for the development of a composition for forming a metal-containing film that has excellent embedding ability and flatness and is used to form a resist underlayer film that can transfer a resist pattern to a substrate to be processed with higher accuracy, and a pattern formation method using the composition.

[0052] The present inventors have focused on metal materials that exhibit superior etching resistance to conventional resist underlayer film materials and have conducted extensive research. However, conventional metal compounds for forming resist underlayer films have poor heat resistance and undergo rapid volumetric shrinkage during baking, making it difficult to fill in steps on the substrate to be processed and flatten it after high-temperature baking. Therefore, the present inventors have hypothesized that volumetric shrinkage of metal compounds during baking can be suppressed by using an additive.

[0053] It has been reported that, as a polyfunctional organic compound used in a metal-containing film-forming composition, for example, a nitrogen-containing organic compound having two or more hydroxyl groups contributes to the stability of the metal compound in the composition (WO2020 / 241712). It has also been reported that polyol functions as an embedding aid (Japanese Patent No. 6810696). Since these additives have hydroxyl groups, they are presumed to be coordinated to metal atoms or free in the metal-containing film-forming composition, and are expected to be less effective in improving embedding because they volatilize or thermally decompose during baking. Japanese Patent No. 6810696 reports that the addition of polyol improves embedding, but this is the result of baking at 250 ° C., and there is no discussion of embedding at higher temperatures required for the formation of a metal oxide film.

[0054] The inventors considered that, when the composition for forming a metal oxide film is in a state where it does not coordinate to the metal, the metal compound reacts with the polyfunctional organic compound during baking, thereby making it possible to suppress the sudden volumetric shrinkage of the metal compound and to fill in steps in the substrate to be processed without generating voids even after high-temperature baking.

[0055] As a result of further intensive research, the present inventors have found that a polyfunctional crosslinking group having a cyclic ether structure having 2 to 13 carbon atoms can improve the reactivity with a metal compound during baking without impairing the stability of the composition for forming a metal-containing film, and can form a metal-containing film with excellent embeddability, thereby completing the present invention.

[0056] That is, the present invention provides a composition comprising: (A) a metal compound containing at least one metal selected from the group consisting of Ti, Zr, and Hf; (B) a crosslinking agent containing 2 to 4 cyclic ether structures having 2 to 13 carbon atoms in the molecule; (C) a solvent; The present invention relates to a composition for forming a metal-containing film, comprising:

[0057] The present invention will be described in detail below, but the present invention is not limited thereto.

[0058] <Metal-containing film forming composition> The metal-containing film-forming composition of the present invention comprises (A) a metal compound containing at least one metal selected from the group consisting of Ti, Zr, and Hf; (B) a crosslinking agent containing 2 to 4 cyclic ether structures having 2 to 13 carbon atoms in the molecule; (C) a solvent; The (A) metal compound (hereinafter also referred to as "metal-containing film-forming compound") can be used in, for example, a metal-containing film-forming composition used in semiconductor manufacturing.

[0059] In the metal-containing film-forming composition of the present invention, each of (A) the metal compound, (B) the crosslinking agent, and (C) the solvent may be used alone or in combination of two or more. Furthermore, the metal-containing film-forming composition may contain components other than the components (A), (B), and (C). Each component will be described below.

[0060] <Metal compounds> The metal compound contained in the metal-containing film-forming composition of the present invention is preferably a compound that contains at least one metal atom selected from the group consisting of Ti, Zr, and Hf and has a metal-oxygen covalent bond.

[0061] By including such a metal, the refractive index of the metal-containing film after heat treatment can be increased, and a metal-containing film having excellent resistance to dry etching using oxygen gas and fluorine gas can be formed.

[0062] The lower limit of the content of the metal element atoms in the (A) metal compound is preferably 5 mass%, more preferably 10 mass%, further preferably 20 mass%, and particularly preferably 30 mass%. The upper limit of the content is preferably 50 mass%. The content of the metal element atoms can be determined by measurement using a differential thermobalance (TG / DTA).

[0063] Such a ratio of metal elements can further improve the refractive index and dry etching resistance to oxygen gas and fluorine gas of the metal-containing film-forming composition.

[0064] The metal atoms contained in the above metal compound may be composed of atoms of one type of element or two or more types of elements, but it is preferable that they are composed of atoms of one type of element, since it is desirable for the etching rate during inorganic film etching transfer processing after fine pattern formation to be uniform within the surface at the nanometer order level.

[0065] The metal compound contains a metal-oxygen atom bond, so that the metal-containing film formed from the metal-containing film-forming composition has excellent etching selectivity. The oxygen atom may be bonded to one metal atom, or may be bonded to multiple metal atoms, but it is preferable that the metal compound mainly contains a structure in which two oxygen atoms are bonded to a metal atom. By mainly containing a structure in which two oxygen atoms are bonded to a metal atom (covalent bond or coordinate bond), the metal compound can have a more linear structure such as -MOMO- (M is a specific metal atom), which can improve the solvent solubility.

[0066] As the (A) metal compound of the present invention, a commercially available metal compound can be used, but for example, a metal-containing compound having a hydrolyzable group (hereinafter referred to as (a) hydrolyzable metal-containing compound) can be used. In addition, the (A) metal compound can be synthesized by a method of carrying out a hydrolysis condensation reaction of the (a) hydrolyzable metal-containing compound. That is, the (A) metal compound can be derived from the (a) hydrolyzable metal-containing compound. Here, the "hydrolysis condensation reaction" refers to a reaction in which the hydrolyzable group of the (a) hydrolyzable metal-containing compound is hydrolyzed and converted to -OH, and the two resulting -OH are dehydration condensed to form -O-.

[0067] As the (A) metal compound of the present invention, it is preferable to use the above-mentioned (a) hydrolyzable metal-containing compound, a hydrolysis and condensation reaction product of the (a) hydrolyzable metal-containing compound, or a compound obtained by reacting these compounds with something that can become a monodentate ligand or a polydentate ligand, and it is more preferable to use the hydrolysis and condensation reaction product of the (a) hydrolyzable metal-containing compound or a compound obtained by reacting the hydrolysis and condensation reaction product of the (a) hydrolyzable metal-containing compound with something that can become a monodentate ligand or a polydentate ligand.

[0068] Such a metal compound (A) reacts well with a crosslinking agent (B) during baking, and a metal-containing film having excellent embedding properties can be formed. From the viewpoint of dry etching resistance, it is more preferable to use a hydrolysis-condensation reaction product of a hydrolyzable metal-containing compound (a) or a compound obtained by reacting a hydrolysis-condensation reaction product of a hydrolyzable metal-containing compound (a) with a substance that can become a monodentate ligand or a polydentate ligand.

[0069] [(a) Hydrolyzable metal-containing compound] The above (a) hydrolyzable metal-containing compound is a metal compound (I) having a hydrolyzable group, a hydrolysate of the metal compound (I), a hydrolysis condensate of the metal compound (I), or a combination thereof. The metal compound (I) may be used alone or in combination of two or more.

[0070] The metal compound (I) may be, for example, a compound (I-1) represented by the following formula (2): By using such a metal compound (I-1), a stable compound (A) can be formed, and the dry etching resistance can be improved. [ka] (In the formula, M is any one of Ti, Zr, and Hf. Ln is independently a monodentate or polydentate ligand having 1 to 30 carbon atoms, and Xn is independently a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, -NR a R b R is a hydrolyzable group selected from the group consisting of a and R b are each independently a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; a+b=4, and a and b are integers of 0 to 4.

[0071] (hydrolyzable group) Examples of the hydrolyzable group Xn in the above general formula (2) include a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, and -NR a R b One or more selected from the following may be mentioned. a and R b are each independently a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms.

[0072] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0073] Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an i-propoxy group, an n-butoxy group, and a t-butoxy group.

[0074] Examples of the carboxylate group include an acetate group, a propionate group, a butyrate group, an n-hexanecarboxylate group, and an n-octanecarboxylate group.

[0075] Examples of the acyloxy group include an acetoxy group, an ethyloxy group, a propionyloxy group, a butyryloxy group, a t-butyryloxy group, a t-amylyloxy group, an n-hexanecarbonyloxy group, and an n-octanecarbonyloxy group.

[0076] Above -NR a R b Examples of the amino group include an unsubstituted amino group, a methylamino group, a dimethylamino group, a diethylamino group, and a dipropylamino group.

[0077] The hydrolyzable group Xn is preferably an alkoxy group, more preferably an i-propoxy group, an n-butoxy group, or a t-butoxy group.

[0078] Examples of the ligand Ln in the above general formula (2) include the following monodentate and polydentate ligands.

[0079] (monodentate ligand) Examples of the monodentate ligand include a hydroxo ligand (OH), a carboxy ligand, an amide ligand, an amine ligand, and an ammonia ligand (NH 3 ), olefin ligands, etc.

[0080] Examples of the carboxy ligand include a formate ligand (OOCH), an acetate ligand (OOCMe), a propionate ligand (OOCEt), and a butyrate ligand (OOCPr).

[0081] The amide ligand may be, for example, an unsubstituted amide ligand (NH 2 ), methylamide ligand (NHMe), dimethylamide ligand (NMe 2 ), diethylamide ligand (NEt 2 ), dipropylamide ligand (NPr 2 ) etc.

[0082] Examples of the amine ligand include pyridine, trimethylamine ligand, and piperidine ligand.

[0083] Examples of the olefin ligand include chain olefins such as ethylene and propylene, and cyclic olefins such as cyclopentene, cyclohexene and norbornene.

[0084] (polydentate ligand) Examples of the polydentate ligand include a ligand derived from a hydroxy acid ester, a ligand derived from a β-diketone, a ligand derived from a β-ketoester, a ligand derived from an α,α-dicarboxylate, a hydrocarbon having a π bond, and a diphosphine.

[0085] Examples of the hydroxy acid ester include glycolic acid ester, lactic acid ester, 2-hydroxycyclohexane-1-carboxylic acid ester, and salicylic acid ester.

[0086] Examples of the β-ketoester include acetoacetate, α-alkyl-substituted acetoacetate, β-ketopentanoate, benzoylacetate, and 1,3-acetonedicarboxylate.

[0087] Examples of the β-diketone include acetylacetone, methylacetylacetone, and ethylacetylacetone.

[0088] Examples of the α,α-dicarboxylic acid ester include malonic acid diesters, α-alkyl-substituted malonic acid diesters, α-cycloalkyl-substituted malonic acid diesters, and α-aryl-substituted malonic acid diesters.

[0089] Examples of the hydrocarbon having a π bond include chain dienes such as butadiene and isoprene, cyclic dienes such as cyclopentadiene, methylcyclopentadiene, pentamethylcyclopentadiene, cyclohexadiene and norbornadiene, and aromatic hydrocarbons such as benzene, toluene, xylene, hexamethylbenzene, naphthalene and indene.

[0090] Examples of the diphosphine include 1,1-bis(diphenylphosphino)methane, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl, and 1,1'-bis(diphenylphosphino)ferrocene.

[0091] In the above general formula (2), a+b=4, and a and b are integers of 0 to 4. a is preferably 0 to 3, more preferably 0 to 2, even more preferably 1 or 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 compound can be increased.

[0092] Examples of the hydrolyzable metal-containing compound (a) include compounds containing titanium, such as diisopropoxybis(2,4-pentanedionato)titanium(IV), tetra n-butoxytitanium(IV), tetra n-propoxytitanium(IV), tri n-butoxymonostearate titanium(IV), titanium(IV) butoxide oligomer, aminopropyltrimethoxytitanium(IV), triethoxymono(2,4-pentanedionato)titanium(IV), tri n-prop ... Examples of compounds containing zirconium include dibutoxybis(ethylacetoacetate)zirconium(IV), di-n-butoxybis(2,4-pentanedionato)zirconium(IV), tetra-n-butoxyzirconium(IV), tetra-n-propoxyzirconium(IV), tetraisopropoxyzirconium(IV), and tetraisopropoxyzirconium(IV). (IV), aminopropyltriethoxyzirconium(IV), 2-(3,4-epoxycyclohexyl)ethyltrimethoxyzirconium(IV), γ-glycidoxypropyltrimethoxyzirconium(IV), 3-isocyanopropyltrimethoxyzirconium(IV), triethoxymono(2,4-pentanedionato)zirconium(IV), tri-n-propoxymono(2,4-pentanedionato)zirconium(IV), triisopropoxymono(2,4-pentanedionato)zirconium(IV), Examples of compounds containing hafnium include diisopropoxybis(2,4-pentanedionato)hafnium(IV), tetrabutoxyhafnium(IV), tetraisopropoxyhafnium(IV), tetraethoxyhafnium(IV), and dichlorobis(cyclopentadienyl)hafnium(IV).

[0093] From the viewpoint of availability of raw materials, the metal compound preferably has a structure represented by the following general formula (3). [ka] (In the formula, M is the same as above, and R 1A is a monovalent organic group having 1 to 20 carbon atoms.

[0094] In the general formula (3), R 1A represents a monovalent organic group having 1 to 20 carbon atoms, preferably a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, or a t-butyl group, more preferably an isopropyl group, an n-butyl group, or a t-butyl group.

[0095] As described above, the (A) metal compound can be the (a) hydrolyzable metal-containing compound itself or its hydrolysis and condensation reaction product, but it can also be a compound obtained by reacting an additional compound as described below.

[0096] During the synthesis reaction of the (A) metal compound, in addition to the (a) hydrolyzable metal-containing compound, a compound that can become a monodentate or polydentate ligand in the metal compound (hereinafter referred to as (b) ligand-forming compound) may be added.

[0097] Examples of the (b) ligand-forming compound include organic compounds derived from hydroxo ligands, carboxy ligands, amide ligands, amine ligands, ammonia ligands, olefin ligands, etc., which are listed as Ln in the above general formula (2), as well as organic compounds derived from ligands derived from hydroxy acid esters, ligands derived from β-diketones, ligands derived from β-ketoesters, ligands derived from α,α-dicarboxylic acid esters, etc., and compounds having multiple hydroxy groups.

[0098] The (A) metal compound can be obtained by reacting a compound derived from the metal compound represented by the formula (2) with an organic compound having 1 to 30 carbon atoms and containing at least one crosslinking group represented by the general formulas (a-1) to (a-4), (b-1) to (b-4), (c-1) to (c-3), and (d-1) to (d-2) described below. In this manner, the crosslinking group can be introduced into the (A) component.

[0099] Furthermore, the (b) ligand-forming compound may be an organic compound having 1 to 30 carbon atoms containing at least one crosslinking group represented by any one of the crosslinking groups represented by the following general formulas (a-1) to (a-4), (b-1) to (b-4), (c-1) to (c-3), and (d-1) to (d-2). [ka] (In the above general formulas (a-1) to (a-4), R a are independently a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, q represents 0 or 1, and * represents a bond. [ka] (In the above general formula, R b are independently a hydrogen atom or a methyl group, which may be the same or different in the same formula; R c is hydrogen, or a substituted or unsubstituted, saturated or unsaturated monovalent organic group having 1 to 20 carbon atoms, a substituted or unsubstituted, aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted, arylalkyl group having 7 to 31 carbon atoms, and * represents a bonding site. [ka] (In the above general formulas (c-1) to (c-3), Y 1 are independently a divalent organic group having 1 to 20 carbon atoms, R is a hydrogen atom, a substituted or unsubstituted saturated monovalent organic group having 1 to 20 carbon atoms or an unsaturated monovalent 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 d are independently an organic group represented by the following general formula (c-4) which generates one or more hydroxyl groups or carboxyl groups by the action of either or both of an acid and heat, and * represents a bond. [ka] (In the above general formula (c-4), R e is an organic group whose protecting group is removed by the action of either acid or heat, or both, and * is Y1 ) [ka] (In the formula, R f is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and * indicates a bond.

[0100] The metal-containing film-forming compound contains at least one crosslinking group represented by any one of the general formulae (a-1) to (a-4), (b-1) to (b-4), (c-1) to (c-3), and (d-1) to (d-2), so that the thermosetting property of the metal compound can be improved. The heat resistance of the metal compound can be improved by the organic crosslinking between the ligands, so that the reaction with the crosslinking agent during baking can be further promoted.

[0101] From the viewpoint of productivity and stability of the metal-containing film-forming compound, the (b) ligand-forming compound is preferably a compound derived from a carboxy ligand, a compound derived from a β-diketone ligand, or a compound having a plurality of hydroxyl groups. These can be used alone or in combination of two or more.

[0102] An example of the compound derived from a carboxy ligand is a compound represented by the following general formula (4). [ka] (In the formula, p is 0 or 1. When p is 1, X 1 is a divalent organic group having 2 to 20 carbon atoms, and W is any one of an alkoxy group having 1 to 10 carbon atoms, the following general formula (4-A), and a crosslinking group represented by the above general formulas (b-1) to (b-4). 1 is a monovalent organic group having 8 to 30 carbon atoms, containing a bridging group having any of the structures represented by the above general formulas (a-2) and (a-3) and an aromatic ring. [ka] (In the above general formula (4-A), Y is a saturated divalent organic group having 1 to 20 carbon atoms or an unsaturated divalent organic group having 2 to 20 carbon atoms, and R A is any of the structures represented by the above general formulas (a-1) to (a-4), h represents 1 to 6, and * represents the bond to the carbon atom of the carbonyl.

[0103] A compound for forming a metal-containing film that contains a carboxy ligand having such a structure has improved heat resistance during baking, and therefore the reaction with the (B) crosslinking agent is more easily promoted, making it possible to form a metal-containing film with better embedding properties.

[0104] In the general formula (4), it is preferable that p is 1 and W is a structure represented by the following general formula (4-B). [ka] (In the above general formula (4-B), R A1 is the structure represented by the above general formula (a-1), and R A2 is either of the structures represented by the above general formula (a-2) or (a-3), Z is either an oxygen atom or a secondary amine, La is a divalent hydrocarbon group having 1 to 10 carbon atoms, and R A3 is a saturated divalent organic group having 1 to 20 carbon atoms or an unsaturated divalent organic group having 2 to 20 carbon atoms, t 1 is 1 to 6, s 1 is 0 to 5, t 1 +s 1 is between 1 and 6, and r 1 is 1 to 10, u is 0 or 1, m 1 is 0 or 1, and * represents the bond to the carbonyl carbon atom.)

[0105] A compound for forming a metal-containing film that contains a carboxy ligand having such a structure has improved heat resistance during baking, and therefore the reaction with the (B) crosslinking agent is more easily promoted, making it possible to form a metal-containing film with better embedding properties.

[0106] In the general formula (4), p is 1, W is an alkoxy group having 1 to 10 carbon atoms, and X 1is preferably any of the structures represented by the following general formula (4-C). [ka] (In the formula, * represents the bond to the carbonyl carbon atom.)

[0107] A compound for forming a metal-containing film that contains a carboxy ligand having such a structure has improved heat resistance during baking, and therefore the reaction with the (B) crosslinking agent is more easily promoted, making it possible to form a metal-containing film with better embedding properties.

[0108] Alternatively, in the general formula (4), p is 0, and X 1 is preferably any of the structures represented by the following formula (4-D). [ka] (In the formula, R 2 is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, and * represents a bond to the carbon atom of the carbonyl. 2 applies only to the above formula.)

[0109] Another example of the compound derived from a carboxy ligand is a compound represented by the following general formula (5). [ka] (In the formula, X 2 is a divalent organic group having 1 to 31 carbon atoms, R 6A is any one of the above general formulas (c-1) to (c-3).

[0110] In the above general formula (5), X 2 is a divalent organic group having 1 to 31 carbon atoms, and from the viewpoint of thermosetting properties, is more preferably a saturated hydrocarbon group having 1 to 20 carbon atoms or an unsaturated hydrocarbon group having 2 to 20 carbon atoms.

[0111] In the above general formulas (c-1) to (c-3), Y 1are independently a divalent organic group having 1 to 20 carbon atoms, and may be a substituted or unsubstituted saturated divalent organic group having 1 to 20 carbon atoms or an unsaturated divalent organic group having 2 to 20 carbon atoms, for example, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or a substituted or unsubstituted arylalkyl group having 7 to 20 carbon atoms; Y 1 is preferably a saturated hydrocarbon group having 1 to 20 carbon atoms or an unsaturated hydrocarbon group having 2 to 20 carbon atoms.

[0112] In the general formulas (c-1) to (c-3), Y 1 is a saturated hydrocarbon group having 1 to 20 carbon atoms or an unsaturated hydrocarbon group having 2 to 20 carbon atoms, the thermosetting property can be further improved when the metal-containing film-forming compound is used as a metal-containing film-forming composition. This is also preferable from the viewpoint of raw material availability.

[0113] Y 1 Specific examples of the structure include, but are not limited to, the following structures. [ka] (* 1 is a bond to an oxygen atom or a nitrogen atom, and * 2 is R 1 )

[0114] In the above general formula (c-4), R e is an organic group from which a thermoacid labile group is eliminated by the action of either or both of an acid and heat, and is preferably a tertiary hydrocarbyl group or a group that forms an acetal structure together with an adjacent oxygen atom, and is particularly preferably a tertiary hydrocarbyl group. The tertiary hydrocarbyl group is preferably one having 4 to 20 carbon atoms, and among these, one having a smaller number of carbon atoms is more preferred.

[0115] A compound for forming a metal-containing film that contains a carboxy ligand having such a structure has improved heat resistance during baking, and therefore the reaction with the (B) crosslinking agent is more easily promoted, making it possible to form a metal-containing film with better embedding properties.

[0116] An example of a compound derived from a ligand derived from a β-diketone is a compound represented by the following general formula (6). [ka] (In the formula, R 6A ~R 6D is a monovalent organic group having 1 to 20 carbon atoms which may contain a hydrogen atom or a crosslinking group represented by any one of the crosslinking groups represented by the above general formulas (a-1) to (a-4), (b-1) to (b-4), and (d-1) to (d-2).

[0117] The compound of the general formula (6) preferably contains at least one crosslinking group represented by any one of the general formulae (a-1) to (a-4), (b-1) to (b-4), and (d-1) to (d-2). Such a compound is preferable because it improves heat resistance during baking, facilitates reaction with the crosslinking agent (B), and allows the formation of a metal-containing film with better embedding properties.

[0118] In the above formula (6), R 6A and R 6D represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms which may contain a bridging group represented by any one of the above general formulae (a-1) to (a-4), (b-1) to (b-4), and (d-1) to (d-2), and is a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, a substituted or unsubstituted allyl group having 2 to 10 carbon atoms, a substituted or unsubstituted ethynyl group having 2 to 10 carbon atoms, or a bridging group represented by any one of the above general formulae (a-1) to (a-4), A monovalent organic group having 1 to 20 carbon atoms which may contain a crosslinking group represented by any one of (b-1) to (b-4) and (d-1) to (d-2) is preferred, and a methyl group, an ethyl group, a phenyl group, an allyloxy group, a propargyloxy group, an alkoxy group having 1 to 10 carbon atoms, or a monovalent organic group having 1 to 20 carbon atoms which may contain a crosslinking group represented by any one of the above general formulas (a-1) to (a-4), (b-1) to (b-4), and (d-1) to (d-2) is more preferred. R 6A and R 6DWhen does not contain a crosslinking group represented by any of the above general formulae (a-1) to (a-4), (b-1) to (b-4), and (d-1) to (d-2), it is preferably a methyl group, a methoxy group, or an ethoxy group.

[0119] R 6B and R 6C represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms which may contain a bridging group represented by any one of the above general formulae (a-1) to (a-4), (b-1) to (b-4), and (d-1) to (d-2), and is a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, a substituted or unsubstituted allyl group having 2 to 10 carbon atoms, a substituted or unsubstituted ethynyl group having 2 to 10 carbon atoms, or a monovalent organic group represented by the above general formula ( A monovalent organic group having 1 to 20 carbon atoms and containing a crosslinking group represented by any one of the general formulae (a-1) to (a-4), (b-1) to (b-4), and (d-1) to (d-2) is preferred, and a hydrogen atom, a methyl group, an ethyl group, a phenyl group, an allyloxy group, a propargyloxy group, or a monovalent organic group having 1 to 20 carbon atoms and containing a crosslinking group represented by any one of the general formulae (a-1) to (a-4), (b-1) to (b-4), and (d-1) to (d-2) is more preferred. 6B and R 6C may be bonded to each other to form a cyclic ether structure. R 6B When R has a substituent other than a hydrogen atom, 6C is preferably a hydrogen atom. 6B and R 6C It is preferable that at least one of R is a hydrogen atom. 6B and R 6C does not contain a bridging group represented by any of the above general formulae (a-1) to (a-4), (b-1) to (b-4), and (d-1) to (d-2), R 6B and R 6C Preferably, both are hydrogen atoms.

[0120] Examples of compounds having a plurality of hydroxy groups include dihydric alcohols represented by any one of the following general formulas (7-A) to (7-C). [ka] (In the formula, R 7a ~R 7b represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms which may contain a crosslinking group represented by any one of the above general formulae (a-1) to (a-4) and (d-1) to (d-2); R 7c ~R 7g is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms which may contain a crosslinking group represented by any one of the above general formulas (a-1) to (a-4), (b-1) to (b-4), and (d-1) to (d-2), and Y is a divalent organic group having 1 to 10 carbon atoms. 7a and R 7b may be bonded to each other to form an unsaturated or saturated ring structure.

[0121] The compounds of the above general formulae (7-A) to (7-C) preferably contain at least one crosslinking group represented by any one of the above general formulae (a-1) to (a-4), (b-1) to (b-4), and (d-1) to (d-2). Such compounds are preferable because they have improved heat resistance during baking, and therefore the reaction with the (B) crosslinking agent is easily promoted, making it possible to form a metal-containing film with better embedding properties.

[0122] In the above formula (7-A), R 7a ~R 7b is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms which may contain a bridging group represented by any one of the above general formulas (a-1) to (a-4) and (d-1) to (d-2), and is preferably a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, a substituted or unsubstituted allyl group having 2 to 10 carbon atoms, a substituted or unsubstituted ethynyl group having 2 to 10 carbon atoms, or a monovalent organic group having 1 to 20 carbon atoms which contains a bridging group represented by any one of the above general formulas (a-1) to (a-4) and (d-1) to (d-2). When R does not contain a bridging group represented by any one of the above general formulas (a-1) to (a-4) and (d-1) to (d-2), 7a and R7b is preferably a hydrogen atom.

[0123] In the above formula (7-B), R 7c and R 7f represents a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms which may contain a crosslinking group represented by any one of the above general formulas (a-1) to (a-4), (b-1) to (b-4), and (d-1) to (d-2), and is preferably a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, and more preferably a hydrogen atom.

[0124] In the above formula (7-B), R 7d R is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms and containing a crosslinking group represented by any one of the above general formulas (a-1) to (a-4), (b-1) to (b-4), and (d-1) to (d-2), and more preferably a monovalent organic group having 1 to 20 carbon atoms and containing a crosslinking group represented by any one of the above general formulas (a-1) to (a-4), (b-1) to (b-4), and (d-1) to (d-2). 7e is a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms which may contain a crosslinking group represented by any one of the above general formulas (a-1) to (a-4), (b-1) to (b-4), and (d-1) to (d-2), more preferably a hydrogen atom or an alkyl or aryl group having 1 to 10 carbon atoms, and even more preferably a hydrogen atom. 7d and R 7e may be bonded to each other to form a cyclic ether structure.

[0125] In the above formula (7-C), R 7g is preferably a monovalent organic group having 1 to 20 carbon atoms containing a crosslinking group represented by any one of the above general formulae (a-1) to (a-4), (b-1) to (b-4), and (d-1) to (d-2). Y is a divalent organic group having 1 to 10 carbon atoms, preferably a divalent hydrocarbon group having 1 to 10 carbon atoms, and from the viewpoint of availability of raw materials, more preferably a hydrocarbon group having 1 to 5 carbon atoms, further preferably a methylene group or an ethylene group, and particularly preferably an ethylene group.

[0126] A compound for forming a metal-containing film that contains a multidentate ligand having such a structure has improved heat resistance during baking, and therefore the reaction with the (B) crosslinking agent is more easily promoted, making it possible to form a metal-containing film with better embedding properties.

[0127] When the metal-containing film-forming compound has a ligand derived from a ligand-forming compound (b) containing any of the groups represented by the above formulas (a-1) to (a-4), (b-1) to (b-4), (c-1) to (c-3), and (d-1) to (d-2), the content of the ligand containing any of the groups represented by the above formulas (a-1) to (a-4), (b-1) to (b-4), (c-1) to (c-3), and (d-1) to (d-2) is preferably 10 mol % to 90 mol %, more preferably 20 mol % to 80 mol %, and even more preferably 25 mol % to 75 mol %, of the total content of the ligands coordinated to the metal atom. The content of the ligand derived from the (b) ligand-forming compound not including the groups represented by the formulae (a-1) to (a-4), (b-1) to (b-4), (c-1) to (c-3), and (d-1) to (d-2) is preferably 0 mol % to 50 mol %, more preferably 0 mol % to 30 mol %, of the total ligands coordinated to the metal atom. The content of the ligand other than the (b) ligand-forming compound, for example, the ligand derived from an alkoxy group having 1 to 10 carbon atoms, is preferably 0 mol % to 90 mol %, more preferably 20 mol % to 80 mol %, of the total ligands coordinated to the metal atom.

[0128] Furthermore, during the synthesis reaction of (A) the metal compound, (c) a silicon-containing compound may be added in addition to (b) the ligand-forming compound.

[0129] By substituting the hydrolyzable group of the (a) hydrolyzable metal-containing compound with a silicon-containing compound, the stability of the (A) metal compound in the metal-containing film-forming composition can be improved.

[0130] Examples of the silicon-containing compound include a structure represented by the following formula (8). [ka] (Above (8) R 8A , R 8B and R 8C is any organic group selected from an organic group having 1 to 30 carbon atoms and a crosslinking group having any of the structures represented by the following general formulas (e-1) to (e-3), a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and an aryl group having 1 to 20 carbon atoms. [ka] (In the above general formulas (e-1) to (e-3), R 3 is hydrogen or a monovalent organic group having 1 to 10 carbon atoms, q is 0 or 1, and * is a bond.

[0131] As the silicon-containing compound, any of the groups represented by the following formulas is more preferable, and trimethylsilanol is more preferable from the viewpoint of productivity. [ka] (In the above formula, * represents a bond to a metal atom.)

[0132] When the (A) metal compound contains the (b) ligand-forming compound and the (c) silicon-containing compound, the content of the (b) ligand-forming compound in the (A) metal compound is preferably 10 mol% to 100 mol% of the total 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 (c) silicon-containing compound-derived ligand is preferably 10 mol% to 90 mol% of the total 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 ligand other than the (b) ligand-forming compound and the (c) silicon-containing compound, for example, the ligand derived from an alkoxy group having 1 to 10 carbon atoms, is preferably 0 mol% to 90 mol% of the total of the ligands coordinated to the metal atom, more preferably 0 mol% to 75 mol%.

[0133] The synthesis method of the (A) metal compound is not particularly limited, but for example, a metal alkoxide or metal acetylacetonate (acac) can be used for the (a) hydrolyzable metal-containing compound, and the alkoxy or acac metal can be reacted with a ligand derived from the (b) ligand-forming compound. The (a) hydrolyzable metal-containing compound may be hydrolyzed and condensed, and then reacted with a ligand derived from the (b) ligand-forming compound, or the (a) hydrolyzable metal-containing compound may be hydrolyzed and condensed after reacting with a ligand derived from the (b) ligand-forming compound. If it is difficult to control the hydrolysis and condensation, the (b) ligand may be reacted with a ligand derived from the ligand-forming compound in a non-water-containing environment. It is preferable to appropriately adjust these according to the properties required for the (A) metal compound and the metal-containing film. In the case where (c) the silicon-containing compound has a ligand derived from (b) the ligand-forming compound as a ligand, it is preferable to react (a) the hydrolyzable metal-containing compound with (c) the silicon-containing compound, and then react the reacted compound with the ligand derived from (b) the ligand-forming compound.

[0134] As a method for carrying out a hydrolysis condensation reaction using (a) a hydrolyzable metal-containing compound, for example, a method of carrying out a hydrolysis condensation reaction of (a) a hydrolyzable metal-containing compound in a solvent containing water can be mentioned. In this case, other compounds having a hydrolyzable group may be added as necessary. In addition, an acid such as acetic acid may be added as a catalyst for the hydrolysis condensation reaction. The lower limit of the amount of water used in this hydrolysis condensation reaction is preferably 0.2 times by mole, more preferably 1 times by mole, and even more preferably 3 times by mole, relative to the hydrolyzable group of (a) a hydrolyzable metal-containing compound or the like. The upper limit of the amount of water is preferably 20 times by mole, more preferably 15 times by mole, and even more preferably 10 times by mole.

[0135] The solvent used in the synthesis reaction of (A) the metal compound is not particularly limited, and for example, the same solvents as those exemplified as (C) solvents described later can be used. Typical solvents and solvent mixtures include ester, ether or alcohol functional groups, for example, a 70 / 30 by volume mixture of propylene glycol monomethyl ether acetate (PGMEA) and propylene glycol monomethyl ether (PGME). Examples of other solvents that can be used include butanediol monomethyl ether, ethylene glycol monomethyl ether, butanediol monoethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, butanediol monopropyl ether, propylene glycol monopropyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, propylene glycol monobutyl ether, 1-butanol, 2-butanol, 2-methyl-1- Examples of the alkoxysilane include propanol, 4-methyl-2-ethanol, 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, t-butyl acetate, t-butyl propionate, propylene glycol mono t-butyl ether acetate, γ-butyrolactone, methyl isobutyl ketone, and cyclopentyl methyl ether.

[0136] <(B) Crosslinking agent> The (B) crosslinking agent contained in the metal-containing film-forming composition of the present invention contains 2 to 4 cyclic ether structures having 2 to 13 carbon atoms in the molecule. It may contain 3 of the cyclic ether structures in the molecule. If the crosslinking agent contains less than 2 or more than 4 of the cyclic ether structures in the molecule, the stability of the metal compound in the composition is impaired, making it impossible to form a metal-containing film with excellent embeddability.

[0137] Such a crosslinking agent can react with the metal compound during baking without impairing the stability of the metal compound in the composition for forming a metal-containing film, thereby suppressing the volumetric shrinkage of the metal compound and forming a metal-containing film with excellent embeddability.

[0138] The cyclic ether structure having 2 to 13 carbon atoms is preferably an epoxy group or an oxetanyl group.

[0139] Such a cyclic ether structure is preferable because it is excellent in terms of reactivity with metal compounds and productivity.

[0140] The crosslinking agent may be a compound or a polymer such as an oligomer or polymer, as long as it contains two or more epoxy or oxetanyl groups in the molecule. When the amount of carbon components in the metal-containing film is large, the dry etching resistance may be deteriorated, so it is preferable to use a monomolecular compound rather than a polymer. The weight-average molecular weight Mw of the polymer may be 1,000 to 10,000, and the weight-average molecular weight Mw and the number-average molecular weight Mn can be determined by gel permeation chromatography (GPC) using tetrahydrofuran as a solvent, as a standard polystyrene equivalent value.

[0141] The (B) crosslinking agent is preferably any of the organic compounds represented by the following formula (1). [ka] (In the above formula (1), X is an m-valent organic group having 1 to 50 carbon atoms, L is a carbonyl group or a divalent organic group having 1 to 10 carbon atoms, and R 1 and R2 are each independently a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms; R 1a is an alicyclic hydrocarbon group having 3 to 10 carbon atoms, l represents 0 or 1, and m represents 2 to 4.

[0142] In the above formula, R 1 is preferably a hydrogen atom, and R 2 is more preferably a hydrogen atom, a methyl group, or an ethyl group, and even more preferably an ethyl group. In the above formula, R 1a represents an alicyclic hydrocarbon group having 3 to 10 carbon atoms, preferably a cycloalkyl group having 5 to 10 carbon atoms, more preferably a cyclopentyl group or a cyclohexyl group.

[0143] In the above formula, L is a carbonyl group or a divalent organic group having 1 to 10 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms, and further preferably a carbonyl group or a methylene group. l is 0 or 1, and more preferably 1.

[0144] In the above formula, X is an m-valent organic group having 1 to 50 carbon atoms, and preferably contains one or more of one or more quaternary carbon atoms, aromatic rings, alicyclic hydrocarbons, or heterocycles.

[0145] Such a crosslinking agent has excellent heat resistance, and therefore is capable of reacting satisfactorily with the metal compound during baking, making it possible to form a metal-containing film with excellent embedding properties.

[0146] Preferred examples of the structure of X include the following.

[0147] [ka] (In the above formula, n is 1 to 5, r is 0 or 1, s is 1 or 2, and R 3 , R 4are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms which may contain a halogen atom, R 5 is a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 10 carbon atoms, and R 6 , R 7 are each independently a hydrogen atom, a hydroxyl group, or an organic group containing an alkyl group, an alkylene group, or an alkynyl group having 1 to 10 carbon atoms; R 8 is a hydrogen atom, a hydroxyl group, or an organic group containing an alkyl group, alkylene group, or alkynyl group having 1 to 10 carbon atoms, and * represents the bonding site with L. The carbon atom in the aromatic ring of the above formula may have a hydroxyl group, a carboxyl group, an ethenyl group, an ethynyl group, an amino group, a sulfide group, or an alkyl group having 1 to 10 carbon atoms which may contain any of these as a substituent.

[0148] Above R 3 , R 4 is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms which may contain a halogen atom, and is a hydrogen atom, a methyl group, CF 3 It is more preferable that the aryl group is one of the groups.

[0149] Above R 5 is a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 10 carbon atoms, and is more preferably a hydrogen atom or a methyl group.

[0150] Above R 6 , R 7 is a hydrogen atom, a hydroxyl group, or an organic group containing an alkyl group, an alkylene group, or an alkynyl group having 1 to 10 carbon atoms, and is more preferably a hydrogen atom, a methyl group, or a hydroxyl group.

[0151] Above R 8 is a hydrogen atom, a hydroxyl group, or an organic group containing an alkyl group, an alkylene group, or an alkynyl group having 1 to 10 carbon atoms, and is more preferably a hydrogen atom, a methyl group, or an allyl group.

[0152] The above n is 1 to 5, more preferably 1 to 3, and even more preferably 1 from the viewpoint of dry etching resistance.

[0153] The above r is 0 or 1, and 0 is more preferable from the viewpoint of dry etching resistance.

[0154] If X is a crosslinking agent having the above structure, it is preferable because it has excellent heat resistance and can react well with the metal compound during baking.

[0155] The amount of the (B) crosslinking agent added is preferably 5 to 100 parts by mass, more preferably 10 to 80 parts by mass, and even more preferably 15 to 60 parts by mass, per 100 parts by mass of the (A) metal compound.

[0156] When the amount of the crosslinking agent (B) added is 5 parts by mass or more, the volumetric shrinkage of the metal compound can be suppressed, and a metal-containing film with excellent embeddability can be formed.When the amount added is 100 parts by mass or less, the amount of outgassing during baking can be suppressed, and a metal-containing film with fewer defects can be formed.

[0157] <(C) Solvent> The (C) solvent that can be used in the metal-containing film-forming composition of the present invention is not particularly limited as long as it dissolves the above-mentioned (A) metal compound and (B) crosslinking agent, as well as the (D) surfactant described below if contained, and other additives.

[0158] Specifically, for example, the organic solvents described in paragraphs

[0091] to

[0092] of JP 2007-199653 A can be added. More specifically, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, 2-heptanone, cyclopentanone, cyclohexanone, γ-butyrolactone, or a mixture containing one or more of these is preferably used.

[0159] (High boiling point solvent) In the metal-containing film-forming composition of the present invention, the (C) solvent may be used as a mixture of one or more organic solvents having a boiling point (value at 1 atmospheric pressure (1013 hPa)) of less than 180°C and one or more organic solvents (high-boiling point solvents) having a boiling point of 180°C or higher.

[0160] The high boiling point solvent is not particularly limited as long as it can dissolve each component of the metal-containing film forming composition of the present invention, and may be any of hydrocarbons, alcohols, ketones, esters, ethers, chlorine-based solvents, etc., but specific examples include 1-octanol, 2-ethylhexanol, 1-nonanol, 1-decanol, 1-undecanol, ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,5-hexanediol, 2,4-heptanediol, 2-ethyl-1,3-Hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, glycerin, n-nonyl acetate, monohexyl ether, ethylene glycol mono-2-ethylhexyl ether, ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, diethylene glycol monoethyl ether, diethylene glycol monoisopropyl ether, diethylene glycol mono-n-butyl ether, diethylene glycol monoisobutyl ether, diethylene glycol monohexyl ether, diethylene glycol monophenyl ether, diethylene glycol monobenzyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol monomethyl ether, triethylene glycol-n-butyl ether, triethylene glycol butyl methyl ether, tetraethylene glycol dimethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-n-butyl ether, tripropylene glycol dimethyl ether, tripropylene glycol monomethyl ether, tripropylene glycol mono-n-propyl ether, tripropylene glycol mono-n-butyl ether, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, triacetin, propylene glycol diacetate, dipropylene glycol methyl-n-propyl ether, dipropylene glycol methyl ether acetate, 1,4-butanediol diacetate, 1,3-butylene glycol diacetate, 1,Examples of the diethyl ester include 6-hexanediol diacetate, triethylene glycol diacetate, γ-butyrolactone, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, dihexyl malonate, diethyl succinate, dipropyl succinate, dibutyl succinate, dihexyl succinate, dimethyl adipate, diethyl adipate, and dibutyl adipate. These may be used alone or in combination.

[0161] The high boiling point solvent may be appropriately selected from the above-mentioned solvents according to the temperature at which the metal-containing film-forming composition of the present invention is heat-treated. The boiling point of the high boiling point solvent is preferably 180°C to 300°C, more preferably 200°C to 300°C. If the solvent has such a boiling point, there is no risk of the solvent volatilizing too quickly during baking (heat treatment), so that the occurrence of defects due to drying during film formation can be suppressed. In addition, if the solvent has such a boiling point, the solvent does not volatilize and remains in the film after baking, so there is no risk of adversely affecting the film properties such as etching resistance.

[0162] The blending amount of the (C) solvent is preferably 200 to 10,000 parts by mass, and more preferably in the range of 250 to 5,000 parts by mass, per 100 parts by mass of the (A) metal compound.

[0163] When the high boiling point solvent is used, the blending amount is preferably 1 to 30 parts by mass per 100 parts by mass of the organic solvent having a boiling point of less than 180° C. Such a blending amount is preferable because it can impart sufficient thermal fluidity during baking and does not remain in the film, leading to deterioration of the film properties such as etching resistance.

[0164] <Other ingredients> When the metal-containing film-forming composition is a metal-containing film-forming composition that can be used as a resist underlayer film in a multilayer resist method, it is sufficient that the composition contains one or more of the above-mentioned (A) metal compound, (B) crosslinking agent, and (C) solvent, and may contain at least one or more of (D) surfactant, (E) thermal acid generator, (F) photoacid generator, and (G) other crosslinking agent as necessary.

[0165] Hereinafter, components that may be contained in the composition for forming a metal-containing film of the present invention other than the above (A) metal compound, (B) crosslinking agent, and (C) solvent will be described.

[0166] [(D) Surfactant] To the metal-containing film-forming composition of the present invention, a surfactant (D) can be added to improve the coating property in spin coating. The surfactant can be used alone or in combination of two or more. For example, the surfactants described in paragraphs

[0142] to

[0147] of JP-A-2009-269953 can be used. When the surfactant is added, the amount of the surfactant 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 compound (A). Within such a range, the coating property is reliably improved, and a thin and uniform adhesive film can be formed.

[0167] [(E) Thermal acid generator] In the metal-containing film-forming composition of the present invention, a thermal acid generator (E) can be added in order to promote the crosslinking reaction caused by heat.

[0168] Examples of the thermal acid generator (E) that can be used in the metal-containing film-forming composition of the present invention include those represented by the following general formula (7).

[0169] [ka] (In the formula, X A - R represents a non-nucleophilic counter ion. 70 , R 71 , R 72 , and R 73each represents a hydrogen atom, or 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, or an aralkyl group or aryloxoalkyl group having 7 to 12 carbon atoms, and some or all of the hydrogen atoms of these groups may be substituted with an alkoxy group or the like. 70 and R 71 , or R 70 , R 71 and R 72 may form a ring, and when a ring is formed, R 70 and R 71 , or R 70 , R 71 and R 72 represents an alkylene group having 3 to 10 carbon atoms, or a heteroaromatic ring having a nitrogen atom in the ring.

[0170] Above, R 70 , R 71 , R 72 , and R 73 may be the same or different, and specific examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopropylmethyl group, a 4-methylcyclohexyl group, a cyclohexylmethyl group, a norbornyl group, and an adamantyl group.

[0171] Examples of the alkenyl group include a vinyl group, an allyl group, a propenyl group, a butenyl group, a hexenyl group, and a cyclohexenyl group.

[0172] Examples of the oxoalkyl group include a 2-oxocyclopentyl group, a 2-oxocyclohexyl group, a 2-oxopropyl group, a 2-cyclopentyl-2-oxoethyl group, a 2-cyclohexyl-2-oxoethyl group, and a 2-(4-methylcyclohexyl)-2-oxoethyl group.

[0173] Examples of the oxoalkenyl group include a 2-oxo-4-cyclohexenyl group and a 2-oxo-4-propenyl group.

[0174] Examples of the aryl group include a phenyl group, a naphthyl group, and the like; alkoxyphenyl groups such as a p-methoxyphenyl group, a m-methoxyphenyl group, an o-methoxyphenyl group, an ethoxyphenyl group, a p-tert-butoxyphenyl group, and a m-tert-butoxyphenyl group; alkylphenyl groups such as a 2-methylphenyl group, a 3-methylphenyl group, a 4-methylphenyl group, an ethylphenyl group, a 4-tert-butylphenyl group, a 4-butylphenyl group, and a dimethylphenyl group; alkylnaphthyl groups such as a methylnaphthyl group and an ethylnaphthyl group; alkoxynaphthyl groups such as a methoxynaphthyl group and an ethoxynaphthyl group; dialkylnaphthyl groups such as a dimethylnaphthyl group and a diethylnaphthyl group; and dialkoxynaphthyl groups such as a dimethoxynaphthyl group and a diethoxynaphthyl group.

[0175] Examples of the aralkyl group include a benzyl group, a phenylethyl group, and a phenethyl group.

[0176] Examples of the aryloxoalkyl group include 2-aryl-2-oxoethyl groups such as a 2-phenyl-2-oxoethyl group, a 2-(1-naphthyl)-2-oxoethyl group, and a 2-(2-naphthyl)-2-oxoethyl group.

[0177] Also, R 70 and R 71 , or R 70 , R 71 and R 72When the nitrogen atom in the formula forms a heteroaromatic ring in the ring, imidazole derivatives (e.g., imidazole, 4-methylimidazole, 4-methyl-2-phenylimidazole, etc.), pyrazole derivatives, furazan derivatives, pyrroline derivatives (e.g., pyrroline, 2-methyl-1-pyrroline, etc.), pyrrolidine derivatives (e.g., pyrrolidine, N-methylpyrrolidine, pyrrolidinone, N-methylpyrrolidone, etc.), imidazoline derivatives, imidazolidine derivatives, pyridine derivatives (e.g., 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, 1-methyl-2-pyridine, Examples of the pyridine derivative include pyridine, 4-pyrrolidinopyridine, 1-methyl-4-phenylpyridine, 2-(1-ethylpropyl)pyridine, aminopyridine, dimethylaminopyridine, etc.), pyridazine derivatives, pyrimidine derivatives, pyrazine derivatives, pyrazoline derivatives, pyrazolidine derivatives, piperidine derivatives, piperazine derivatives, morpholine derivatives, indole derivatives, isoindole derivatives, 1H-indazole derivatives, indoline 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, uridine derivatives, and the like.

[0178] Above, X A -Examples of the non-nucleophilic counter ion include halide ions such as chloride ion and bromide ion; fluoroalkyl sulfonates such as triflate, 1,1,1-trifluoroethanesulfonate, and nonafluorobutanesulfonate; aryl sulfonates such as tosylate, benzenesulfonate, 4-fluorobenzenesulfonate, and 1,2,3,4,5-pentafluorobenzenesulfonate; alkyl sulfonates such as mesylate and butanesulfonate; imide acids such as bis(trifluoromethylsulfonyl)imide, bis(perfluoroethylsulfonyl)imide, and bis(perfluorobutylsulfonyl)imide; methide acids such as tris(trifluoromethylsulfonyl)methide and tris(perfluoroethylsulfonyl)methide; and sulfonates substituted with fluoro at the α-position as shown in the following general formula (8) and sulfonates substituted with fluoro at the α- and β-positions as shown in the following general formula (9).

[0179] [ka]

[0180] In the above general formula (8), R 81 is a hydrogen atom, a linear, branched, or cyclic alkyl group having 1 to 23 carbon atoms, an acyl group, an alkenyl group having 2 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aryloxy group. 91 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.

[0181] Specific examples of the thermal acid generator include, but are not limited to, the following.

[0182] [ka]

[0183] The thermal acid generator (E) contained in the metal-containing forming composition of the present invention can be used alone or in combination of two or more. The amount of the thermal acid generator added is preferably 0.05 to 30 parts by mass, more preferably 0.1 to 10 parts by mass, based on 100 parts by mass of the metal compound (A). If it is 0.05 parts by mass or more, the amount of acid generated and the crosslinking reaction are sufficient, and if it is 30 parts by mass or less, there is little risk of a mixing phenomenon occurring due to the acid migrating to the upper resist layer.

[0184] From the viewpoint of improving the embeddability of uneven substrates, it is preferable that the metal-containing film-forming composition of the present invention does not contain a thermal acid generator. The action of the acid generator promotes self-condensation of the metal compound, which may inhibit the reaction with the crosslinking agent and deteriorate the embeddability.

[0185] [(F) Photoacid generator] In order to appropriately adjust the pattern shape, exposure sensitivity, etc. of the resist upper layer film, the composition for forming the metal-containing film of the present invention can contain (F) a photoacid generator. The photoacid generator can be used alone or in combination of two or more. As the photoacid generator, for example, those described in paragraphs

[0160] to

[0179] of JP-A-2009-126940 can be used. The amount of the photoacid generator added is preferably 0.05 to 30 parts by mass, more preferably 0.1 to 10 parts by mass, based on 100 parts by mass of the above-mentioned (A) metal compound. If the amount of the photoacid generator added is within the above range, the resolution is good, and there is no risk of foreign matter problems occurring after resist development or during peeling.

[0186] [(G) Other crosslinking agents] In addition to the (B) crosslinking agent, the metal-containing film-forming composition of the present invention may also contain (G) other crosslinking agents in order to enhance curability and further suppress intermixing with the resist upper layer film. The crosslinking agent is not particularly limited, and various known crosslinking agents can be widely used. Examples include melamine-based crosslinking agents, glycoluril-based crosslinking agents, benzoguanamine-based crosslinking agents, urea-based crosslinking agents, β-hydroxyalkylamide-based crosslinking agents, isocyanurate-based crosslinking agents, aziridine-based crosslinking agents, oxazoline-based crosslinking agents, and phenol-based crosslinking agents. The (G) other crosslinking agents may be used alone or in combination of two or more. The amount of the crosslinking agent added is preferably 5 to 50 parts by mass, more preferably 10 to 40 parts by mass, relative to 100 parts by mass of the (A) metal compound. If the amount added is 5 parts by mass or more, sufficient curability is exhibited and intermixing with the resist upper layer film can be suppressed. On the other hand, when the amount added is 50 parts by mass or less, there is no risk of deterioration in dry etching resistance due to a low ratio of the (A) metal compound in the composition.

[0187] [Plasticizer] A plasticizer can be added to the metal-containing film-forming composition of the present invention. The plasticizer is not particularly limited, and various known plasticizers can be widely used. Examples include low molecular weight compounds such as phthalates, adipic esters, phosphates, trimellitates, and citrates, and polymers such as polyethers, polyesters, and polyacetal polymers described in JP-A-2013-253227. The amount of the plasticizer to be added is preferably 1% by mass to 500% by mass with respect to 100 parts by mass of the (A) metal compound. When the amount is within such a range, the pattern filling and averaging are excellent.

[0188] <Metal-containing film formation method> In the present invention, the above-mentioned metal-containing film-forming composition can be used to form a filling film that functions as a resist underlayer film of a multi-layer resist film used in lithography or a planarizing film for semiconductor manufacturing.

[0189] In the method for forming a resist underlayer film or a filling film using the composition for forming a metal-containing film of the present invention, the composition for forming a metal-containing film is coated on a substrate to be processed by spin coating or the like. By using the spin coating or the like, good embedding properties can be obtained. After spin coating, the solvent is evaporated, and baking (heat treatment) is performed to promote a crosslinking reaction in order to prevent mixing with the resist upper layer film or the resist intermediate film. The baking is preferably performed at 100°C or higher and 600°C or lower for 10 to 600 seconds, more preferably at 200°C or higher and 500°C or lower for 10 to 300 seconds. Considering the influence on device damage and wafer deformation, the upper limit of the heating temperature in the wafer process of lithography is preferably 600°C or lower, more preferably 500°C or lower.

[0190] In addition, in the above-mentioned film formation method using the metal-containing film-forming composition of the present invention, the metal-containing film-forming composition of the present invention can be coated on a substrate to be processed by a spin coating method or the like as described above, and the metal-containing film-forming composition can be baked and cured in an atmosphere having an oxygen concentration of 0.1 vol.% or more and 21 vol.% or less, thereby forming a metal-containing film as a resist underlayer film.

[0191] By baking the metal-containing film-forming composition of the present invention in such an oxygen atmosphere, a sufficiently hardened film can be obtained. The atmosphere during baking may be air, but N 2 It is preferable to seal an inert gas such as Ar or He in order to prevent oxidation of the metal-containing film. In order to prevent oxidation, it is necessary to control the oxygen concentration, which is preferably 1,000 ppm or less, and more preferably 100 ppm or less (volume basis). Preventing oxidation of the metal-containing film during baking is preferable because it prevents increased absorption and reduced etching resistance.

[0192] The above method is preferable because it can form an amorphous metal-containing film. From the viewpoint of dry etching resistance, it is preferable that the metal-containing film is amorphous. If the metal-containing film is amorphous, ions are less likely to be scattered, making vertical dry etching easier, and there is no risk of crystal grains deteriorating the roughness of the pattern.

[0193] <Pattern formation method using the composition for forming a metal-containing film> The present invention also provides a pattern forming method using the above-mentioned metal-containing film forming composition. Below, the pattern forming method by the multi-layer resist process using the metal-containing film forming composition of the present invention will be described with examples, but the present invention is not limited to the following aspects. In the following multi-layer resist process, the resist top layer film, the resist middle film, and the resist bottom layer film are arranged in this order from the side farthest from the substrate to be processed.

[0194] In the present invention, a method for forming a pattern by a two-layer resist process using the above-mentioned composition for forming a metal-containing film is a method for forming a pattern on a substrate to be processed, comprising the steps of: (I-1) a step of applying the composition for forming a metal-containing film described above onto a substrate to be processed, followed by heat treatment to form a metal-containing film; (I-2) forming a resist top layer film on the metal-containing film using a photoresist material; (I-3) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (I-4) a step of transferring the pattern to the metal-containing film by dry etching using the resist top layer film on which the pattern is formed as a mask; and (I-5) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. The present invention provides a pattern forming method comprising the steps of:

[0195] Since the resist top layer film in the two-layer resist process exhibits etching resistance to chlorine-based gases, it is preferable that the dry etching of the metal-containing film in the two-layer resist process is performed using the resist top layer film as a mask with an etching gas mainly containing a chlorine-based gas.

[0196] In addition, the present invention provides a method for forming a pattern by a three-layer resist process using the above-mentioned composition for forming a metal-containing film, which is a method for forming a pattern on a substrate to be processed, comprising the steps of: (II-1) forming a resist underlayer film on a substrate to be processed; (II-2) a step of applying the above-described composition for forming a metal-containing film onto the resist underlayer film, followed by heat treatment to form a metal-containing film; (II-3) forming a resist top layer film on the metal-containing film using a photoresist material; (II-4) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (II-5) a step of transferring the pattern to the metal-containing film by dry etching using the resist upper layer film on which the pattern is formed as a mask; (II-6) a step of transferring a pattern to the resist underlayer film by dry etching using the metal-containing film to which the pattern has been transferred as a mask; (II-7) a step of processing the substrate using the resist underlayer film on which the pattern is formed as a mask to form a pattern on the substrate; The present invention provides a pattern forming method comprising the steps of:

[0197] The resist top layer film of the above three-layer resist process shows resistance to etching by chlorine-based gas, so in the above three-layer resist process, the dry etching of the metal-containing film is preferably performed by using the resist top layer film as a mask, using an etching gas mainly made of chlorine-based gas.Then, the metal-containing film shows resistance to etching by oxygen-based gas, so the dry etching of the resist underlayer film is preferably performed by using the metal-containing film as a mask, using an etching gas mainly made of oxygen-based gas.When an organic underlayer film is used as the resist underlayer film, it shows resistance to etching by fluorine-based gas, so the dry etching of the substrate to be processed is preferably performed by using the organic underlayer film as a mask, using an etching gas mainly made of fluorine-based gas.

[0198] In the present invention, in such a multilayer resist process, the above-mentioned composition for forming a metal-containing film may be used to directly form a metal-containing film on a substrate to be processed as a resist underlayer film, or a resist underlayer film may be formed on the substrate to be processed and then a metal-containing film may be formed separately.

[0199] In addition, the present invention provides a method for forming a pattern by a three-layer resist process using such a composition for forming a metal-containing film, which is a method for forming a pattern on a substrate to be processed, comprising the steps of: (III-1) A step of applying the composition for forming a metal-containing film described above onto a substrate to be processed, followed by heat treatment to form a metal-containing film; (III-2) forming a silicon-containing resist intermediate film on the metal-containing film; (III-3) forming a resist upper layer film on the silicon-containing resist intermediate film using a photoresist material; (III-4) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (III-5) a step of transferring a pattern to the silicon-containing resist intermediate film by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (III-6) A step of transferring a pattern to the metal-containing film by dry etching using the silicon-containing resist intermediate film to which the pattern has been transferred as a mask; and (III-7) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. The present invention provides a pattern forming method comprising the steps of:

[0200] A pattern formation method by a three-layer resist process will be described with reference to Fig. 1. In the present invention, as a pattern formation method by a three-layer resist process using such a metal-containing film-forming composition, as shown in Fig. 1(A), a metal-containing film 3 is formed on a processable layer 2 on a processable substrate 1 using the metal-containing film-forming composition, a silicon-containing resist intermediate film 4 is formed on the metal-containing film using a silicon-containing resist intermediate film material, and a resist upper layer film 5 is formed on the silicon-containing resist intermediate film using a photoresist material. Subsequently, as shown in FIG. 1(B), an exposed portion 6 of the resist top layer film is exposed to a pattern, and then, as shown in FIG. 1(C), it is developed with a developer to form a resist top layer film pattern 5a on the resist top layer film. As shown in FIG. 1(D), a silicon-containing resist intermediate film pattern 4a is transferred to the silicon-containing resist intermediate film by dry etching using the resist top layer film on which the pattern has been formed as a mask. As shown in FIG. 1(E), a metal-containing film pattern 3a is transferred to the metal-containing film by dry etching using the silicon-containing resist intermediate film on which the pattern has been transferred as a mask. As shown in FIG. 1(F), a pattern forming method is provided in which the processable layer on the processable substrate is processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern 2a on the processable substrate 1.

[0201] Since the silicon-containing resist intermediate film in the above three-layer resist process exhibits etching resistance to chlorine-based gas, it is preferable that the dry etching of the metal-containing film in the above three-layer resist process is performed using the silicon-containing resist intermediate film as a mask, using an etching gas mainly composed of a chlorine-based gas.

[0202] As the silicon-containing resist intermediate film in the above three-layer resist process, a polysiloxane-based intermediate film is also preferably used. By imparting an anti-reflection effect to the silicon-containing resist intermediate film, reflection can be suppressed. In particular, for 193 nm exposure, if a material containing many aromatic groups and having high etching selectivity with the substrate is used as the organic film, the k value becomes high and the substrate reflection becomes high, but by imparting absorption to the silicon-containing resist intermediate film to an appropriate k value, it becomes possible to suppress reflection, and the substrate reflection can be reduced to 0.5% or less. As the silicon-containing resist intermediate film having an anti-reflection effect, a polysiloxane that is pendant with an anthryl group for 248 nm and 157 nm exposure, and a phenyl group or a light-absorbing group having a silicon-silicon bond for 193 nm exposure, and is crosslinked with acid or heat is preferably used.

[0203] Additionally, the present invention may be a pattern forming method using a four-layer resist process further including a step of forming an organic thin film.

[0204] As a pattern formation method by a four-layer resist process using such a composition for forming a metal-containing film, the present invention provides a method for forming a pattern on a substrate to be processed, comprising the steps of: A step of applying the composition for forming a metal-containing film described above onto a substrate to be processed, followed by heat treatment to form a metal-containing film; forming a silicon-containing resist intermediate film on the resist underlayer film; forming an organic thin film on the silicon-containing resist intermediate film; forming a resist top layer film on the organic thin film using a photoresist material; a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; a step of transferring a pattern to the organic thin film and the silicon-containing resist intermediate film by dry etching using the resist upper layer film on which the pattern has been formed as a mask; A step of transferring a pattern to the metal-containing film by dry etching using the silicon-containing resist intermediate film to which the pattern has been transferred as a mask; and A step of processing the substrate to be processed using the metal-containing film on which the pattern is formed as a mask to form a pattern on the substrate to be processed. The pattern forming method can be characterized by comprising the steps of:

[0205] The organic thin film is not particularly limited, but is preferably a functional film having a desired function in a multilayer resist process, and can be, for example, an organic antireflective coating (BARC) or an adhesion film.

[0206] As a pattern forming method by a four-layer resist process further including a step of forming an organic antireflective coating (BARC) or an adhesion film as the organic thin film, for example, forming a metal-containing film on a substrate to be processed using the composition for forming a metal-containing film; forming a silicon-containing resist intermediate film on the metal-containing film using a silicon-containing resist intermediate film material; forming an organic antireflective coating (BARC) or an adhesion film as an organic thin film on the silicon-containing resist intermediate film; forming a resist top layer film on the BARC or the adhesion film using a photoresist material; The resist upper layer film is exposed to a pattern and then developed with a developer to form a pattern on the resist upper layer film; Using the resist top layer film on which the pattern is formed as a mask, a pattern is transferred to the BARC or the adhesion film and the silicon-containing resist intermediate film by dry etching; Using the silicon-containing resist intermediate film to which the pattern has been transferred as a mask, a pattern is transferred to the metal-containing film by dry etching; The method may include a step of processing the substrate to be processed using the metal-containing film on which the pattern is formed as a mask to form a pattern on the substrate to be processed.

[0207] In addition, an inorganic hard mask intermediate film may be formed instead of the silicon-containing resist intermediate film. In this case, at least A metal-containing film is formed on a substrate to be processed using the composition for forming a metal-containing film of the present invention; forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film on the metal-containing film; forming a resist upper layer film on the inorganic hard mask intermediate film using a photoresist composition, and forming a circuit pattern on the resist upper layer film; The pattern is transferred to the inorganic hard mask intermediate film using the resist upper layer film on which the pattern is formed as a mask; transferring a pattern to the metal-containing film using the patterned inorganic hard mask intermediate film as a mask; Furthermore, by processing the substrate to be processed using the metal-containing film on which the pattern is formed as a mask to form a pattern on the substrate to be processed, a semiconductor device circuit pattern or the like can be formed on the substrate.

[0208] In the present invention, a pattern forming method including a step of forming an inorganic hard mask intermediate film is a method for forming a pattern on a substrate to be processed, comprising the steps of: (IV-1) A step of applying the composition for forming a metal-containing film described above onto a substrate to be processed, followed by heat treatment to form a metal-containing film; (IV-2) forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film on the metal-containing film; (IV-3) forming an organic thin film on the inorganic hard mask intermediate film; (IV-4) forming a resist top layer film on the organic thin film using a photoresist material; (IV-5) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (IV-6) a step of transferring a pattern to the organic thin film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film on which the pattern is formed as a mask; (IV-7) a step of transferring a pattern to the metal-containing film by dry etching using the inorganic hard mask intermediate film to which the pattern has been transferred as a mask; and (IV-8) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. The present invention provides a pattern forming method comprising the steps of:

[0209] As described above, when forming an inorganic hard mask intermediate film on a metal-containing film, a silicon oxide film, a silicon nitride film, and a silicon oxide nitride film (SiON film) can be formed by a CVD method, an ALD method, or the like. For example, methods for forming a silicon nitride film are described in JP-A-2002-334869 and WO-A-2004 / 066377. The thickness of the inorganic hard mask intermediate film is preferably 5 to 200 nm, more preferably 10 to 100 nm. In addition, a SiON film, which has a high effect as an anti-reflection film, is most preferably used as the inorganic hard mask intermediate film. Since the substrate temperature when forming the SiON film is 300 to 500° C., it is preferable that the metal-containing film can withstand a temperature of 300 to 500° C. The metal-containing film-forming composition used in the present invention has high heat resistance and can withstand high temperatures of 300 to 500° C., so that it is possible to combine an inorganic hard mask intermediate film formed by a CVD method or an ALD method with a metal-containing film formed by a spin coating method.

[0210] A photoresist film may be directly formed on the inorganic hard mask intermediate film as a resist top layer, or as described above, an organic thin film such as an organic anti-reflective coating (BARC) or an adhesion film may be formed on the inorganic hard mask intermediate film by spin coating, and then a photoresist film may be formed on top of that. In particular, when a SiON film is used as the inorganic hard mask intermediate film, the two-layer anti-reflective film of the SiON film and the BARC makes it possible to suppress reflection even in immersion exposure with a high NA exceeding 1.0. Another advantage of forming the BARC is that it has the effect of reducing the tailing of the photoresist pattern directly above the SiON film.

[0211] In the above pattern forming method, the resist upper layer film may be either positive or negative, and may be the same as a commonly used photoresist composition. The photoresist composition may contain metal atoms such as Sn, In, Ga, Ge, Al, Ce, La, Cs, Zr, Hf, Ti, Bi, Sb, and Zn. When forming the resist upper layer film using the above photoresist composition, it may be formed by spin coating or deposition processing using CVD or ALD.

[0212] When forming a photoresist upper layer film by spin coating, pre-baking is performed after resist coating, preferably at 60 to 180° C. for 10 to 300 seconds. After that, exposure is performed according to a conventional method, post-exposure baking (PEB) and development are performed to obtain a resist pattern. The thickness of the resist upper layer film is not particularly limited, but is preferably 10 to 500 nm, particularly preferably 20 to 400 nm.

[0213] When forming a resist top layer film by deposition processing by CVD or ALD, the photoresist composition is an EUV photosensitive metal oxide-containing film, and the metal is selected from Sn, Zr, Hf, Ti, Bi, Sb, etc., among which Sn, which has excellent EUV photosensitivity, is preferred. The metal oxide-containing film may be a photosensitive organometallic oxide film such as an organotin oxide (e.g., haloalkyl Sn, alkoxyalkyl Sn, or amidoalkyl Sn). Some specific examples of suitable precursors include trimethyltin chloride, dimethyltin dichloride, methyltin trichloride, tris(dimethylamino)methyltin(IV), and (dimethylamino)trimethyltin(IV).

[0214] Metal oxide containing films may be deposited by PECVD or PEALD, for example using a Lam Vector® tool, with the Sn oxide precursor being separate from the O precursor / plasma in the ALD example. The deposition temperature is preferably in the range of 50° C. to 600° C. The deposition pressure is preferably between 100 and 6,000 mTorr. The flow rate of the metal oxide containing film precursor liquid (e.g., organotin oxide precursor) may be 0.01 to 10 cmm, and the gas flow rate (CO 2 , CO, Ar, N 2 ) may be 100-10,000 sccm. Plasma power may be 200-1,000 W per 300 mm wafer station using high frequency plasma (e.g., 13.56 MHz, 27.1 MHz, or higher). Deposition thickness is preferably 100-2,000 Å.

[0215] Examples of the exposure light include high energy rays with a wavelength of 300 nm or less, specifically, excimer lasers with wavelengths of 248 nm, 193 nm, and 157 nm, soft X-rays with wavelengths of 3 to 20 nm, electron beams, and X-rays.

[0216] The method for forming the pattern on the resist upper layer film is preferably photolithography with a wavelength of 5 nm or more and 300 nm or less, direct drawing with an electron beam, nanoimprinting, or a combination of these.

[0217] In the pattern forming method, the development method is preferably alkaline development or development using an organic solvent.

[0218] Next, etching is performed using the obtained resist pattern as a mask. In the three-layer resist process, etching of the silicon-containing resist intermediate film and the inorganic hard mask intermediate film is performed using a fluorocarbon-based gas and the resist upper layer film pattern as a mask. This forms a silicon-containing resist intermediate film pattern and an inorganic hard mask intermediate film pattern.

[0219] Next, the metal-containing film is etched using the silicon-containing resist intermediate film pattern or the inorganic hard mask intermediate film pattern as a mask. The etching of the metal-containing film is preferably performed using an etching gas mainly composed of a chlorine-based gas.

[0220] The next etching of the substrate can also be carried out by a conventional method. For example, if the substrate is SiO 2 For SiN or silica-based low dielectric constant insulating films, etching is mainly performed using fluorocarbon gases. When etching is performed using fluorocarbon gases for substrate processing, the silicon-containing resist intermediate film pattern in the three-layer resist process is peeled off at the same time as the substrate is processed.

[0221] The metal-containing film obtained by using the metal-containing film-forming composition of the present invention is characterized by excellent etching resistance when etching the substrate to be processed.

[0222] The workpiece (substrate) is not particularly limited, and may be Si, α-Si, p-Si, SiO 2 The substrate may be made of a material such as SiN, SiON, W, TiN, or Al, or a substrate having a layer to be processed formed thereon. 2 Various low-k films and their stopper films such as SiON, SiN, p-Si, α-Si, W, W-Si, Al, Cu, and Al-Si are used, and can be formed to a thickness of usually 50 to 10,000 nm, particularly 100 to 5,000 nm. When forming a processed layer, the substrate and the processed layer are made of different materials.

[0223] In the pattern forming method using the metal-containing film forming composition of the present invention, it is preferable to use a substrate to be processed having a structure or step having a height of 30 nm or more. As described above, since the metal-containing film forming composition of the present invention has excellent filling / flattening properties, even if the substrate to be processed has a structure or step (unevenness) having a height of 30 nm or more, a flat metal-containing film can be formed. The height of the structure or step of the substrate to be processed is preferably 30 nm or more, more preferably 50 nm or more, and more preferably 100 nm or more. In the method for processing a stepped substrate having a pattern of the above height, the metal-containing film forming composition of the present invention is formed into a film and filled / flattened, thereby making it possible to uniformize the film thickness of the silicon-containing resist intermediate film and resist top layer film to be formed thereafter, which is very preferable, since it is easy to ensure the exposure depth margin (DOF) during photolithography.

[0224] Furthermore, the present invention may further include a step of forming an organic underlayer film using an organic underlayer film material. forming a metal-containing film on a substrate to be processed using the composition for forming a metal-containing film; forming an organic underlayer film on the metal-containing film using an organic underlayer film material; forming a silicon-containing resist intermediate film on the organic underlayer film using a silicon-containing resist intermediate film material; If necessary, an organic antireflective coating (BARC) or an adhesion film is formed on the silicon-containing resist intermediate film; forming a resist top layer film on the silicon-containing resist intermediate film, on the BARC, or on the adhesion film using a photoresist material; The resist upper layer film is exposed to a pattern and then developed with a developer to form a pattern on the resist upper layer film; Using the resist top layer film on which the pattern is formed as a mask, a pattern is transferred to the BARC or the adhesion film and the silicon-containing resist intermediate film by dry etching; using the silicon-containing resist intermediate film to which the pattern has been transferred as a mask, transferring the pattern to an organic underlayer film by dry etching; transferring a pattern to the metal-containing film using the organic underlayer film as a mask; The present invention provides a pattern forming method, comprising the step of processing the substrate to be processed using the metal-containing film on which the pattern is formed as a mask to form a pattern on the substrate to be processed.

[0225] As the organic underlayer film material that can be used for the organic underlayer film, those already known as underlayer films for three-layer resist method or two-layer resist method using silicon resist composition, 4,4'-(9-fluorenylidene)bisphenol novolac resin (molecular weight 11,000) described in JP-A-2005-128509, and many other resins including novolac resins, known as resist underlayer film materials for two-layer resist method or three-layer resist method, etc. can be used. In addition, when it is desired to increase heat resistance more than that of normal novolac, a polycyclic skeleton such as 6,6'-(9-fluorenylidene)-di(2-naphthol) novolac resin can be introduced, and further a polyimide resin can be selected (for example, JP-A-2004-153125).

[0226] The organic underlayer film can be formed on the metal-containing film by spin coating or the like using a composition solution in the same manner as the photoresist composition. After forming the organic underlayer film by spin coating or the like, it is desirable to bake the film to evaporate the organic solvent. The baking temperature is preferably in the range of 80 to 400°C, and the baking time is preferably in the range of 10 to 300 seconds.

[0227] Instead of the organic underlayer film, an organic hard mask formed by a CVD method or an ALD method can also be used.

[0228] Since the organic underlayer film in the above multilayer resist process exhibits etching resistance to chlorine-based gases, it is preferable that the dry etching of the metal-containing film in the above multilayer resist process is performed using the organic underlayer film as a mask by using an etching gas mainly containing a chlorine-based gas.

[0229] In addition, the present invention provides a method for forming a pattern by another multilayer resist process using such a composition for forming a metal-containing film, which is a method for forming a pattern on a substrate to be processed, comprising the steps of: (V-1) a step of applying the composition for forming a metal-containing film described above onto a substrate to be processed, followed by heat treatment to form a metal-containing film; (V-2) forming an organic intermediate film on the metal-containing film; (V-3) forming a silicon-containing resist intermediate film or a combination of an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film and an organic thin film on the organic intermediate film; (V-4) forming a resist top layer film on the silicon-containing resist intermediate film or the organic thin film using a photoresist material; (V-5) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (V-6) a step of transferring a pattern to the silicon-containing resist intermediate film or the organic thin film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (V-7) a step of transferring a pattern to an organic intermediate film by dry etching using the silicon-containing resist intermediate film or the inorganic hard mask intermediate film to which the pattern has been transferred as a mask; (V-8) a step of transferring a pattern to the metal-containing film by dry etching using the organic intermediate film as a mask; and (V-9) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. The present invention provides a pattern forming method comprising the steps of:

[0230] By the pattern formation method by the multilayer resist process using the metal-containing film-forming composition of the present invention, a fine pattern can be formed on a workpiece with high accuracy.

[0231] <Method of forming a tone-reversal pattern using a composition for forming a metal-containing film> In addition, the present invention provides a tone-reversal pattern forming method using such a metal-containing film-forming composition, which is a method for forming a pattern on a substrate to be processed, comprising the steps of: (VI-1) forming a resist underlayer film on a substrate to be processed; (VI-2) forming a silicon-containing resist intermediate film or a combination of an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film and an organic thin film on the resist underlayer film; (VI-3) forming a resist upper layer film on the silicon-containing resist intermediate film or the combination of the inorganic hard mask intermediate film and the organic thin film using a photoresist material; (VI-4) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (VI-5) a step of transferring a pattern to the silicon-containing resist intermediate film, or the organic thin film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (VI-6) a step of transferring a pattern to the resist underlayer film by dry etching using the silicon-containing resist intermediate film or the inorganic hard mask intermediate film to which the pattern has been transferred as a mask; (VI-7) a step of applying the above-described composition for forming a metal-containing film onto the resist underlayer film on which the pattern has been formed, and then heat-treating the composition to form a metal-containing film, thereby filling spaces between the resist underlayer film patterns with the metal-containing film; (VI-8) a step of etching back the metal-containing film covering the resist underlayer film on which the pattern is formed by a chemical stripper or dry etching to expose an upper surface of the resist underlayer film on which the pattern is formed; (VI-9) a step of removing the silicon-containing resist intermediate film or hard mask intermediate film remaining on the upper surface of the resist underlayer film by dry etching; (VI-10) a step of removing the resist underlayer film on which the pattern is formed and the surface is exposed by dry etching to form a reverse pattern of the original pattern on the metal-containing film; (VI-11) A step of processing the substrate to be processed using the metal-containing film on which the reverse pattern is formed as a mask to form a reverse pattern on the substrate to be processed. 13. A method for forming a tone-reversal pattern comprising:

[0232] A tone-reversal pattern forming method using a metal-containing film-forming composition will be described with reference to Fig. 2. In the present invention, as a tone-reversal pattern forming method using such a metal-containing film-forming composition, as shown in Fig. 2(G), a resist underlayer film 7 formed from a coating-type organic underlayer film material or the like is formed on a processable layer 2 on a processable substrate 1, a silicon-containing resist intermediate film 4 or a combination of an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film and an organic thin film is formed on the resist underlayer film 7, and a resist upper layer film 5 is formed on the silicon-containing resist intermediate film 4 or the combination of an inorganic hard mask intermediate film and an organic thin film using a photoresist material.Subsequently, as shown in FIG. 2(H), the exposed portion 6 of the resist upper layer film is pattern-exposed, and then developed with a developer as shown in FIG. 2(I) to form a resist upper layer film pattern 5a on the resist upper layer film. As shown in FIG. 2(J), the resist upper layer film on which the pattern is formed is used as a mask to transfer the silicon-containing resist intermediate film pattern 4a or the inorganic hard mask intermediate film pattern to the silicon-containing resist intermediate film 4, or the organic thin film and the inorganic hard mask intermediate film by dry etching. As shown in FIG. 2(K), the silicon-containing resist intermediate film or the inorganic hard mask intermediate film on which the pattern is transferred is used as a mask to transfer the resist underlayer film pattern 7a to the resist underlayer film by dry etching. As shown in FIG. 2(L), the resist underlayer film on which the pattern is formed is coated with a metal-containing film 8 using the above-mentioned metal-containing film-forming composition, and the resist underlayer film pattern 7a is formed between the resist underlayer film patterns 7a. The method includes the steps of filling the resist underlayer film with the metal-containing film 8, etching back the metal-containing film 8 covering the resist underlayer film on which the pattern is formed by a chemical stripper or dry etching to form a metal-containing film pattern 8a which is an inversion of the resist underlayer film pattern, exposing the upper surface of the resist underlayer film on which the pattern is formed, removing the silicon-containing resist intermediate film or inorganic hard mask intermediate film remaining on the upper surface of the resist underlayer film pattern 7a by dry etching as shown in FIG. 2(N), removing the resist underlayer film on which the pattern is formed and the exposed surface by dry etching as shown in FIG. 2(O), forming an inversion pattern of the original pattern in the metal-containing film, and processing the processed layer using the metal-containing film on which the inversion pattern is formed as a mask to form an inversion pattern 2a in the processed layer as shown in FIG. 2(P).

[0233] As described above, when forming a resist underlayer film on a substrate to be processed, the resist underlayer film can be formed by a method using a coating type resist underlayer film material, a CVD method, an ALD method, or the like. Coating-type resist underlayer film materials include those described in JP 2012-001687 A, JP 2012-077295 A, JP 2004-264710 A, JP 2005-043471 A, JP 2005-250434 A, JP 2007-293294 A, JP 2008-065303 A, JP 2004-205685 A, JP 2007-171895 A, JP 2009-014816 A, JP 2007-199653 A, JP 2008-274250 A, JP 2010-122656 A, JP 2012 Examples of resins and compositions include those disclosed in JP-A-214720, JP-A-2014-029435, WO 2012 / 077640, WO 2010 / 147155, WO 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, and JP-A-2019-044022.

[0234] In the above-mentioned tone reversal pattern forming method, it is preferable to coat the obtained resist underlayer film pattern with a metal-containing film forming composition, and then remove the metal-containing film using a dry etching gas mainly composed of a chlorine-based gas to expose the upper surface of the resist underlayer film pattern. Then, the silicon-containing resist intermediate film or the inorganic hard mask intermediate film remaining on the resist underlayer film is removed by dry etching with a fluorocarbon-based gas, and the exposed surface of the resist underlayer film pattern is removed by dry etching with an oxygen-based gas to form a metal-containing film pattern.

[0235] In the tone reversal patterning method, the resist underlayer film pattern preferably has a structure or step having a height of 30 nm or more. As described above, the metal-containing film-forming composition of the present invention has excellent filling / flattening properties, so that even if the processed film has a structure or step (unevenness) having a height of 30 nm or more, a flat metal-containing film can be formed. The height of the structure or step of the resist underlayer film pattern is preferably 30 nm or more, more preferably 50 nm or more, and more preferably 100 nm or more. In the method for reversing a resist underlayer film pattern having a pattern of the above height, the metal-containing film-forming composition of the present invention is formed into a film and filled / flattened, so that the reversal / transfer of the pattern can be performed with high accuracy, which is very preferable. Compared to the resist underlayer film using the conventional coating-type resist underlayer film material, the composition has excellent resistance to dry etching using a fluorocarbon-based gas, so that the resist underlayer film pattern can be reversed with the metal-containing film-forming composition to form a desired resist pattern on the processed film with high accuracy. EXAMPLES

[0236] 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 to these.

[0237] [Synthesis example] In the following synthesis examples, the organic group raw material group G: (G1) to (G11) and the silicon-containing organic group raw material group H: (H1) to (H2) shown below were used.

[0238] The organic group raw materials G: (G1) to (G11) are shown below. [ka]

[0239] Silicon-containing organic group raw materials H: (H1) to (H2) are shown below. [ka]

[0240] As the metal source M, the following metal compounds were used. (M1): Titanium tetraisopropoxide (Sigma-Aldrich Corp, 377996) (M2): Zr (OnBu) 4 : Zirconium(IV) tetrabutoxide (80% by mass solution in 1-butanol) (Tokyo Chemical Industry Co., Ltd., Z0016) (M3): Hf (OnBu) 4 : Hafnium(IV) n-butoxide (Sigma-Aldrich Corp, 667943)

[0241] [Synthesis Example 1] Synthesis of metal-containing film-forming compound (A-1) Under a nitrogen atmosphere, a solution of 54.5 g of n-butanol in 1.6 g of deionized water was dropped into 40.5 g of n-butanol solution of 28.4 g of titanium tetraisopropoxide (M1) over 2 hours at room temperature while stirring. 11.2 g of organic group raw material group (G1) was added to the obtained solution and stirred at room temperature for 30 minutes. After concentrating this solution at 30°C under reduced pressure, it was further heated to 60°C and continued to be heated under reduced pressure until no distillate was produced. When no distillate was observed, 69.0 g of PGMEA / PGME (mass ratio 70 / 30) solution was added and heated at 40°C under reduced pressure until IPA was no longer distilled, to obtain a PGMEA / PGME solution of the metal-containing film-forming compound (A-1). The concentration of components other than the solvent in the solution was 17% by mass.

[0242] [Synthesis of compounds (A-2) to (A-11)] Compounds (A-2) to (A-11) shown in Table 1 were obtained under the same reaction conditions as in Synthesis Example 1, except that the metal source M and compound group G were used in the amounts shown in Table 1. [Table 1]

[0243] [Synthesis Example 2] Synthesis of metal-containing film-forming compound (A-12) Under a nitrogen atmosphere, 12.6 g of titanium tetraisopropoxide (M1) was dissolved in 23.4 g of PGMEA / PGME (mass ratio 70 / 30) solution, and the reaction temperature was increased to 50° C. while stirring, and 6.5 g of compound H1 was dropped into the solution. After dropping, the reaction temperature was set to 60° C. and stirring was continued for 2 hours. Next, a mixture obtained by suspending 5.4 g of compound G4 in 10.8 g of PGMEA / PGME (mass ratio 70 / 30) solution was added to the reaction system, and stirring was continued for 1 hour while keeping the reaction temperature at 60° C. After cooling to room temperature, the resulting reaction solution was filtered through a 0.45 μm PTFE filter to obtain a PGMEA / PGME solution of the metal-containing film-forming compound (A-12). The concentration of components other than the solvent in the solution was 15% by mass.

[0244] [Synthesis of compounds (A-12) to (A-15)] Compounds (A-12) to (A-15) shown in Table 2 were obtained under the same reaction conditions as in Synthesis Example 2, except that the metal source M, compound group G, and compound group H were used in the amounts shown in Table 2. [Table 2]

[0245] [Crosslinking agents B-1 to B-14)] The crosslinking agents (B-1) to (B-14) used in the metal-containing film-forming composition are shown below. The following were used for B-6, 7, and 13. B-6: ETERNACOLL (registered trademark) OXIPA manufactured by UBE Corporation B-7: OXT-121 manufactured by Toagosei Co., Ltd. B-13: ETERNACOLL (registered trademark) OXBP manufactured by UBE Corporation [ka]

[0246] [Comparative crosslinking agents (R-1 to R-6)] Comparative crosslinking agents (R-1) to (R-6) used in the comparative metal-containing film-forming compositions are shown below: R-2 was OXT-212 manufactured by Toagosei Co., Ltd. [ka]

[0247] [Preparation of metal-containing film-forming composition (MUL-1)] The metal-containing film-forming compound (A-1) was dissolved in a mixed solvent of propylene glycol monomethyl ether acetate (PGMEA) and propylene glycol monomethyl ether (PGME) in the ratio shown in Table 3, and the solution was filtered through a 0.02 μm membrane filter to prepare a metal-containing film-forming composition (MUL-1).

[0248] [Preparation of metal-containing film-forming compositions (MUL-2 to 17) and comparative metal-containing film-forming compositions (Comparative Examples MUL-1 to 10)] Each chemical solution was prepared in the same manner as MUL-1, except that the type and content of each component were as shown in Table 3. In Table 3, "-" indicates that the corresponding component was not used. Ethylene glycol dibenzyl ether (boiling point 364°C) was used as the high boiling point solvent (D-1), and the acid generator (TAG) represented by the following formula (E-1) was used. [ka]

[0249] [Table 3]

[0250] [Thickness uniformity evaluation] The resist underlayer film forming compositions (MUL-1 to 17, Comparative Examples MUL-1 to 9) prepared above were applied onto a 300 mm silicon substrate and baked at 350° C. for 60 seconds. The film thickness of the 300 mm wafer from the center to the outer periphery was then measured at 225 points. If the difference between the maximum and minimum film thicknesses was less than 3% of the average film thickness (b), it was rated as A (very good), if it was 3% or more but less than 5%, it was rated as B (good), and if it was 5% or more, it was rated as C (poor). In Comparative Example 1-9, the evaluation was discontinued because a precipitate was generated after the above sample preparation. (B) It is presumed that the compound (R-6) used as the crosslinking agent contains many hydroxyl groups, and reacted with the metal compound to generate a precipitate. [Table 4]

[0251] The metal-containing film-forming composition of the present invention (Examples 1-1 to 1-17) showed good results in terms of film thickness uniformity. It is presumed that this is because the (A) metal compound and the (B) crosslinking agent reacted well. In particular, the composition using the (B) crosslinking agent having a ring structure showed extremely good film thickness uniformity. On the other hand, Comparative Examples 1-1 to 1-3 formed only with the metal-containing film-forming compound showed insufficient film thickness uniformity after high-temperature baking. In addition, in Comparative Example 1-4, the crosslinking agent R-1 for the comparative example is a polymer having a cyclic ether structure in the repeating unit and is highly reactive, so the proportion of self-crosslinking is high. It is presumed that this resulted in insufficient reaction with the metal compound, resulting in deterioration of heat resistance. It is presumed that in Comparative Example 1-5, the crosslinking agent R-2 for the comparative example is monofunctional and has insufficient heat resistance, so that the film thickness uniformity was not improved. Comparative Examples 1-6 and 1-7, which used multifunctional crosslinkers (R-3 and R-4), and Comparative Example 1-8, which used a crosslinker with excellent heat resistance (R-5), showed some improvement in film thickness uniformity compared to Comparative Example 1-1, which had a composition consisting of only a metal compound.

[0252] [Evaluation of embedding characteristics] The compositions prepared above (MUL-1 to 17 and Comparative Examples MUL-1 to 8) were each used as SiO films having three types of dense line and space patterns. 2The solution was applied onto a wafer substrate (substrate A) and heated at 350° C. for 60 seconds using a hot plate to form a metal-containing film with a thickness of 80 nm. Pattern A: line width 60 nm, line depth 120 nm, distance between the centers of two adjacent lines 120 nm Pattern B: Line width 50 nm, line depth 120 nm, distance between the centers of two adjacent lines 100 nm Pattern C: line width 40 nm, line depth 120 nm, distance between the centers of two adjacent lines 80 nm

[0253] The substrate A used was a base substrate 9 (SiO 2 The cross-sectional shape of each wafer substrate obtained in the filling evaluation was observed using an electron microscope (S-4700) manufactured by Hitachi, Ltd., to check whether or not there were voids (air gaps) at the bottom of the metal-containing film that filled the gaps between the lines. The results are shown in Table 5.

[0254] When a metal-containing film-forming composition with good filling properties is used, a void-free metal-containing film 10 is formed at the bottom of the metal-containing film that fills the spaces between the lines of a base substrate 9 having a dense line and space pattern, as shown in Figure 3(S).When a metal-containing film-forming composition with poor filling properties is used, a void 11 is generated at the bottom of the metal-containing film that fills the spaces between the lines, as shown in Figure 3(T). It is preferable to be able to embed pattern A, it is more preferable to be able to embed pattern B having a finer pattern, and it is even more preferable to be able to embed pattern C having an even finer pattern. [Table 5]

[0255] As shown in Table 5, in Examples 2-1 to 2-17 in which the metal-containing film-forming compositions of the present invention (MUL-1 to 17) were used, it was possible to fill a dense line and space pattern in Pattern A without generating voids at the bottom of the pattern even after baking at 350°C, and it was confirmed that the composition had good filling properties even under high-temperature baking conditions.

[0256] In particular, Examples 2-4 to 2-11 using metal compounds (A-4 to A-11) having a ligand containing a crosslinking group showed excellent embedding properties even in the finer patterns B and A. It is presumed that the metal compound having a ligand containing a crosslinking group structure improved the heat resistance of the metal compound and further improved the reactivity with the (B) crosslinking agent. Examples using metal compounds (A-12 to A-15) in which the hydrolyzable group was substituted with a silicon-containing group showed insufficient embedding properties in the finer pattern A. It is presumed that the presence of an alkoxy group as the hydrolyzable group further promotes the reaction with the (B) crosslinking agent. Furthermore, the metal-containing film-forming composition (MUL-3) in which the (B) crosslinking agent contains an aromatic ring structure exhibited superior embedding properties in pattern B compared to the metal-containing film-forming compositions (MUL-1 and 2) in which the (B) crosslinking agent does not contain an aromatic ring structure. This is presumably because the (B) crosslinking agent contains an aromatic ring structure, the heat resistance of the crosslinking agent is improved, and the reactivity with the (A) metal compound is further improved.

[0257] For MUL-17, the occurrence of voids was observed in pattern C. It is presumed that the inclusion of an acid generator (A) promoted the self-condensation of the metal compound and (B) reduced the reactivity with the crosslinker, which resulted in greater volumetric shrinkage of the metal compound on the fine substrate (pattern C), which is more susceptible to heat from the substrate, and thus the occurrence of voids. Comparative Example MUL-2 does not contain (B) a crosslinking agent, but does contain a metal compound (A-7) having a ligand containing a crosslinking group structure, which is believed to have improved the heat resistance of the metal compound and enabled the pattern A to be filled without voids. On the other hand, in Comparative Examples MUL-1 and MUL-3, which did not contain (B) a crosslinking agent and were composed of a metal compound having no ligand containing a crosslinking group structure, the occurrence of voids was observed in all patterns.

[0258] In Comparative Examples 2-4 to 2-8, which used compounds for forming metal-containing films (Comparative Examples MUL-4 to 8) in which the (B) crosslinking agent did not contain two or more cyclic ether structures having 2 to 13 carbon atoms in the molecule, unlike the compounds for forming metal-containing films of the present invention, voids were observed at the bottom of the finer patterns B and C after baking at 350° C. It is presumed that these voids were generated because the reactivity between the (A) metal compound and the (B) crosslinking agent was poor and the heat resistance of the metal-containing film was insufficient, resulting in large volume shrinkage due to high-temperature baking.

[0259] [Etching resistance evaluation] The metal-containing film-forming compositions (MUL-1 to 17, and comparative examples MUL-1 to 8, 10) were applied onto silicon substrates and heated at 350°C for 60 seconds using a hot plate to form metal-containing films with a thickness of 80 nm, and the film thickness a was measured. Next, etching was performed under the following conditions (conditions 1 and 2) using a Tokyo Electron etching device TE8500, and the film thickness b was measured. The film thickness etched per minute was calculated as the etching rate (nm / min) from the film thickness etched during the specified time (film thickness b - film thickness a). In the case of condition 1, an etching rate of 50 nm / min or less was rated A (very good), a rate of more than 50 nm / min and less than 70 nm / min was rated B (good), and a rate of more than 70 nm / min was rated C (poor). In the case of condition 2, an etching rate of 50 nm / min or less was rated A (very good), a rate of more than 50 nm / min and less than 70 nm / min was rated B (good), and a rate of more than 70 nm / min was rated C (poor). The results are shown in Table 6.

[0260] Dry etching condition 1 Pressure: 200mT RF power: 300W CF 4 Gas flow rate: 100sccm Time: 20sec

[0261] Dry etching condition 2 Pressure: 500mT RF power: 100W O 2 Gas flow rate: 30sccm N 2 Gas flow rate: 270sccm Time: 20sec

[0262] [Table 6]

[0263] As shown in Table 6, in Examples 3-1 to 3-17 in which the metal-containing film-forming compositions (MUL-1 to 17) of the present invention were used, it was found that they exhibited excellent dry etching resistance against fluorine gas and oxygen gas, respectively. In particular, it was found that the metal-containing film-forming compositions containing a metal compound having a multidentate ligand exhibited extremely excellent dry etching resistance. In addition, it is presumed that the comparative example MUL-4 used the polymer (R-1) as the crosslinking agent (B) and therefore the amount of carbon components contained in the metal-containing film increased, resulting in a deterioration in dry etching resistance. In Comparative Example 3-9, a resin (R-5) that can be used as an organic underlayer film was evaluated, but the result was that the dry etching resistance to the metal-containing film was insufficient.

[0264] [Pattern formation method] The above-mentioned metal-containing film-forming compositions (MUL-1 to 17) were each applied to a SiO 2The coating was applied onto a wafer substrate and baked in air at 350°C for 60 seconds to form a metal-containing film with a thickness of 80 nm. An organic underlayer film material (SOC-1) was applied thereon and baked at 350°C for 60 seconds to form an organic underlayer film with a thickness of 150 nm, a silicon-containing resist intermediate film material (SOG-1) was applied thereon and baked at 220°C for 60 seconds to form a silicon-containing resist intermediate film (hereinafter also referred to as a resist intermediate film) with a thickness of 30 nm, and a single layer resist for ArF of the resist upper layer film material was applied thereon and baked at 105°C for 60 seconds to form a photoresist film with a thickness of 100 nm. An immersion protective film material (TC-1) was applied on the photoresist film and baked at 90°C for 60 seconds to form a protective film with a thickness of 50 nm.

[0265] A coating type organic underlayer film material (SOC-1) was prepared by dissolving the polymer shown in Organic Underlayer Film Polymer (SOP1) in an organic solvent containing 0.1 mass % of FC-4430 (manufactured by Sumitomo 3M) in the ratio shown in Table 7 and filtering the resultant through a fluorine resin filter having a pore size of 0.2 μm.

[0266] [Table 7]

[0267] The structural formula of the organic underlayer polymer (SOP1) used is shown in Table 8. [Table 8]

[0268] The silicon-containing resist intermediate film material (SOG-1) was prepared by dissolving the polymer represented by ArF silicon-containing intermediate film polymer (SiP1) and the thermal crosslinking catalyst (CAT1) in an organic solvent containing 0.1 mass% FC-4430 (manufactured by Sumitomo 3M) in the ratios shown in Table 9, and filtering the solution through a fluorine resin filter having a pore size of 0.1 μm.

[0269] [Table 9]

[0270] The structural formulae of the ArF silicon-containing intermediate film polymer (SiP1) and thermal crosslinking catalyst (CAT1) used are shown below. [ka]

[0271] The resist top layer film material (ArF single layer resist) was prepared by dissolving a polymer (RP1), an acid generator (PAG1), and a basic compound (Amine1) in a solvent containing 0.1 mass % of a surfactant FC-4430 (Sumitomo 3M Limited) in the ratios shown in Table 10, and filtering the solution through a 0.1 μm fluorine resin filter.

[0272] [Table 10]

[0273] The polymer (RP1), acid generator (PAG1), and basic compound (Amine1) used in the resist top layer material (ArF single layer resist) are shown below. [ka]

[0274] The immersion protective film material (TC-1) was prepared by dissolving the protective film polymer (PP1) in an organic solvent in the ratio shown in Table 11, and filtering through a 0.1 μm fluorine resin filter.

[0275] [Table 11]

[0276] The protective film polymer (PP1) used in the immersion protective film material (TC-1) is shown below. [ka]

[0277] Next, the film was exposed using an ArF immersion exposure apparatus (Nikon Corporation; NSR-S610C, NA 1.30, σ 0.98 / 0.65, 35 degree dipole s-polarized illumination, 6% halftone phase shift mask), baked at 100°C for 60 seconds (PEB), and developed in a 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution for 30 seconds to obtain a 60 nm 1:1 positive line and space pattern (resist upper layer film pattern).

[0278] Next, the resist intermediate film is etched by dry etching using the resist upper layer film pattern as a mask to form a resist intermediate film pattern, the organic underlayer film is etched using the obtained resist intermediate film pattern as a mask to form an organic underlayer film pattern, the metal-containing film is etched using the obtained organic underlayer film pattern as a mask to form a metal-containing film pattern, and the SiO 2 The film was etched using a ULVAC etching device, CE-300I, under the following conditions:

[0279] Transfer conditions of the resist top layer pattern to the resist intermediate layer. CF 4 Gas dry etching conditions Pressure: 1Pa Antenna RF power: 100W Bias RF power: 15W CF 4 Gas flow rate: 15sccm Time: 60sec

[0280] Transfer conditions of the resist intermediate film pattern to the organic underlayer film. O 2 Gas dry etching conditions Pressure: 1Pa Antenna RF power: 300W Bias RF power: 0W O 2 Gas flow rate: 25sccm Time: 40sec

[0281] Conditions for transferring organic underlayer film patterns to metal-containing films. Cl 2 Gas dry etching conditions Pressure: 1Pa Antenna RF power: 320W Bias RF power: 30W Cl 2 Gas flow rate: 25sccm Time: 45 seconds

[0282] Metal-containing film patterned SiO 2 Membrane transfer conditions. CF 4 Gas dry etching conditions Pressure: 1Pa Antenna RF power: 100W Bias RF power: 15W CF 4 Gas flow rate: 15sccm Time: 60sec

[0283] The cross section of the pattern was observed using an electron microscope (S-4700) manufactured by Hitachi, Ltd. The results are shown in Table 12. [Table 12]

[0284] As shown in Table 12, in Examples 4-1 to 4-17 in which the metal-containing film-forming composition of the present invention (MUL-1 to 17) was used, the resist upper layer film pattern was ultimately transferred successfully to the substrate in all cases, confirming that the metal-containing film-forming composition of the present invention is suitable for use in fine processing using the multilayer resist method.

[0285] [SOC pattern inversion method] SiO 2A coating type resist underlayer film material (SOC-1) was applied as a resist underlayer film on a silicon wafer substrate on which a film was formed, and baked at 350°C for 60 seconds to form a resist underlayer film with a thickness of 120 nm, a silicon-containing resist intermediate film material (SOG-1) was applied on top of that and baked at 220°C for 60 seconds to form a resist intermediate film with a thickness of 30 nm, and a single layer resist for ArF, which is a resist upper layer film material, was applied on top of that and baked at 105°C for 60 seconds to form a photoresist film with a thickness of 100 nm. An immersion protective film material (TC-1) was applied on the photoresist film and baked at 90°C for 60 seconds to form a protective film with a thickness of 50 nm.

[0286] The organic underlayer film material (SOC-1), silicon-containing resist intermediate film material (SOG-1), resist toplayer film material (ArF single layer resist), and immersion protective film material (TC-1) on the photoresist film were the same as those used in the pattern formation method described above (Example 4).

[0287] Next, the film was exposed using an ArF immersion exposure apparatus (Nikon Corporation; NSR-S610C, NA 1.30, σ 0.98 / 0.65, 35 degree dipole s-polarized illumination, 6% halftone phase shift mask), baked at 100°C for 60 seconds (PEB), and developed in a 2.38 mass% tetramethylammonium hydroxide (TMAH) aqueous solution for 30 seconds to obtain a 60 nm 1:1 positive line and space pattern (resist upper layer film pattern).

[0288] Next, the resist intermediate film was etched by dry etching using the resist upper layer film pattern as a mask using a Tokyo Electron etching device Telius to form a hard mask pattern, and the resist lower layer film (SOC-1) was etched using the obtained hard mask pattern as a mask to form a SOC-1 film pattern. The etching conditions are as shown below.

[0289] Transfer conditions of the resist top layer pattern to the resist intermediate layer. Chamber pressure: 50mT RF power (top): 500W RF power (bottom): 300W CF 4 Gas flow rate: 150sccm CHF 3 Gas flow rate: 50sccm Time: 20sec

[0290] Conditions for transferring the hard mask pattern to the resist underlayer film. Chamber pressure: 10mT RF power (top): 1,000W RF power (bottom): 300W CO 2 Gas flow rate: 150sccm CO gas flow rate: 50sccm N 2 Gas flow rate: 50sccm H 2 Gas flow rate: 150sccm Time: 100sec

[0291] Next, the above-mentioned metal-containing film-forming compositions (MUL-1 to 17, Comparative Examples MUL-1, 4 to 6) were applied onto the obtained SOC-1 film pattern, and baked in air at 350°C for 60 seconds to form a metal-containing film with a thickness of 80 nm. Thereafter, the metal-containing film covering the SOC-1 film pattern was etched to expose the upper surface of the SOC-1 film pattern. The resist intermediate film remaining on the surface of the SOC-1 film pattern with the upper surface exposed was removed by etching, and then the exposed SOC-1 film pattern was removed by etching, and the above pattern was inverted onto the metal-containing film, and the obtained metal-containing film pattern was used as a mask to perform a SiO 2 As a comparative example, the metal-containing film-forming composition was not used, and the SOC-1 film pattern was used as a mask to etch the SiO 2 The film was also etched (Comparative Example 5-5) under the following etching conditions.

[0292] Conditions for etching back metal-containing film (exposing SOC-1 film pattern). Pressure: 1Pa Antenna RF power: 320W Bias RF power: 30W Cl 2 Gas flow rate: 25sccm Time: 20sec

[0293] Removal of the resist intermediate film remaining on the SOC-1 film pattern. CF 4 Gas dry etching conditions Pressure: 1Pa Antenna RF power: 100W Bias RF power: 15W CF 4 Gas flow rate: 15sccm Time: 45 seconds

[0294] Removal of SOC-1 membrane pattern. O 2 Gas dry etching conditions Pressure: 1Pa Antenna RF power: 300W Bias RF power: 0W O 2 Gas flow rate: 25sccm Time: 35sec

[0295] Metal-containing film patterned SiO 2 Membrane transfer conditions. CF 4 Gas dry etching conditions Pressure: 1Pa Antenna RF power: 100W Bias RF power: 15W CF 4 Gas flow rate: 15sccm Time: 60sec

[0296] Comparative Example 5-9: SiO of SOC-1 film pattern 2 Membrane transfer conditions. CF 4 Gas dry etching conditions Pressure: 1Pa Antenna RF power: 100W Bias RF power: 15W CF 4 Gas flow rate: 15sccm Time: 60sec

[0297] The cross section of the pattern was observed using an electron microscope (S-4700) manufactured by Hitachi, Ltd. The results are shown in Table 13. [Table 13]

[0298] As shown in Table 13, in Examples 5-1 to 5-17 in which the metal-containing film-forming composition of the present invention (MUL-1 to 17) was used, the SOC-1 film pattern was accurately reversed in all cases, and the reversed pattern was ultimately transferred satisfactorily to the substrate without pattern collapse. From this, it was confirmed that the metal-containing film-forming composition of the present invention is suitably used for microfabrication using a tone reversal etching method in a multilayer resist process. On the other hand, when the SOC-1 film pattern is directly formed on SiO 2 In Comparative Example 5-5, which was transferred to a film, the etching resistance of the SOC-1 film was insufficient, and thus distortion of the pattern shape was confirmed. In addition, in Comparative Examples 5-1 to 5-4, in which insufficient performance was confirmed in the embedding characteristic evaluation (Pattern A), the metal-containing film was not filled up to the bottom between the SOC-1 film patterns, and therefore the pattern could not be inverted, and ultimately a good inverted pattern could not be obtained.

[0299] From the above, it has become clear that the metal-containing film-forming composition of the present invention has both high filling / planarization properties and dry etching resistance, and is therefore extremely useful as a resist underlayer film material used in a multilayer resist method and as a reversal agent used in a tone reversal etching method, and that the pattern formation method of the present invention using this composition can form fine patterns with high precision even if the workpiece is a substrate having steps.

[0300] The present specification includes the following aspects. [1]: (A) a metal compound containing at least one metal selected from the group consisting of Ti, Zr, and Hf; (B) a crosslinking agent containing 2 to 4 cyclic ether structures having 2 to 13 carbon atoms in the molecule; (C) a solvent; A composition for forming a metal-containing film, comprising: [2]: The metal-containing film-forming composition according to [1], wherein the (B) crosslinking agent has two or more epoxy groups or oxetanyl groups in the molecule. [3]: The metal-containing film-forming composition according to [1] or [2], wherein the (B) crosslinking agent is any one of organic compounds represented by the following formula (1): [ka] (In the above formula (1), X is an m-valent organic group having 1 to 50 carbon atoms, L is a carbonyl group or a divalent organic group having 1 to 10 carbon atoms, and R 1 and R 2 are each independently a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms; R 1a is an alicyclic hydrocarbon group having 3 to 10 carbon atoms, l represents 0 or 1, and m represents 2 to 4. [4]: The metal-containing film-forming composition according to [3], wherein X in the formula (1) is an m-valent organic group containing one or more of a quaternary carbon atom, an aromatic ring, an alicyclic hydrocarbon, or a heterocycle. [5]: The composition for forming a metal-containing film according to [3] or [4], wherein X in the formula (1) is any one of the following structures: [ka] (In the above formula, n is 1 to 5, r is 0 or 1, s is 1 or 2, and R 3 , R 4 are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms which may contain a halogen atom, R 5 is a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 10 carbon atoms, and R 6 , R 7are each independently a hydrogen atom, a hydroxyl group, or an organic group containing an alkyl group, an alkylene group, or an alkynyl group having 1 to 10 carbon atoms; R 8 is a hydrogen atom, a hydroxyl group, or an organic group containing an alkyl group, alkylene group, or alkynyl group having 1 to 10 carbon atoms, and * represents the bonding site with L. The carbon atom in the aromatic ring of the above formula may have a hydroxyl group, a carboxyl group, an ethenyl group, an ethynyl group, an amino group, a sulfide group, or an alkyl group having 1 to 10 carbon atoms which may contain any of these as a substituent. [6]: The composition for forming a metal-containing film according to any one of [1] to [5], characterized in that the (A) metal compound is derived from a metal compound represented by the following formula (2): [ka] (In the formula, M is any one of Ti, Zr, and Hf. Ln is independently a monodentate or polydentate ligand having 1 to 30 carbon atoms, and Xn is independently a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, -NR a R b R is a hydrolyzable group selected from the group consisting of a and R b are each independently a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; a+b=4, and a and b are integers of 0 to 4. [7]: The composition for forming a metal-containing film according to [6], wherein the formula (2) is a structure represented by the following formula (3): [ka] (Wherein, M is Ti, Zr, or Hf; R 1A is a monovalent organic group having 1 to 20 carbon atoms. [8]: The metal-containing film-forming composition according to [6] or [7], wherein the (A) metal compound is a reaction product of a compound derived from the metal compound represented by the formula (2) with an organic compound having 1 to 30 carbon atoms and containing at least one crosslinking group represented by the following general formulas (a-1) to (a-4), (b-1) to (b-4), (c-1) to (c-3), and (d-1) to (d-2): [ka] (In the above general formulas (a-1) to (a-4), R a are independently a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, q represents 0 or 1, and * represents a bond. [ka] (In the above general formula, R b are independently a hydrogen atom or a methyl group, which may be the same or different in the same formula; R c is hydrogen, or a substituted or unsubstituted, saturated or unsaturated monovalent organic group having 1 to 20 carbon atoms, a substituted or unsubstituted, aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted, arylalkyl group having 7 to 31 carbon atoms, and * represents a bonding site. [ka] (In the above general formulas (c-1) to (c-3), Y 1 are independently a divalent organic group having 1 to 20 carbon atoms, R is a hydrogen atom, a substituted or unsubstituted saturated monovalent organic group having 1 to 20 carbon atoms or an unsaturated monovalent 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 d are independently an organic group represented by the following general formula (c-4) which generates one or more hydroxyl groups or carboxyl groups by the action of either or both of an acid and heat, and * represents a bond. [ka] (In the above general formula (c-4), R e is an organic group whose protecting group is removed by the action of either acid or heat, or both, and * is Y 1 ) [ka] (In the formula, R f is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and * indicates a bond. [9]: The composition for forming a metal-containing film according to any one of [1] to [8], characterized in that the amount of the (B) crosslinking agent added is 5 to 100 parts by mass per 100 parts by mass of the (A) metal compound.

[10] : The composition for forming a metal-containing film according to any one of [1] to [9], characterized in that the (C) solvent is a mixture of one or more organic solvents having a boiling point of less than 180°C and one or more organic solvents having a boiling point of 180°C or higher.

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

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

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

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

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

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

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

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

[15] : The pattern forming method according to

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

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

[10] onto a substrate to be processed, and then performing a heat treatment to form a metal-containing film; (V-2) forming an organic intermediate film on the metal-containing film; (V-3) forming a silicon-containing resist intermediate film or a combination of an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film and an organic thin film on the organic intermediate film; (V-4) forming a resist top layer film on the silicon-containing resist intermediate film or the organic thin film using a photoresist material; (V-5) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (V-6) a step of transferring a pattern to the silicon-containing resist intermediate film or the organic thin film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (V-7) a step of transferring a pattern to an organic intermediate film by dry etching using the silicon-containing resist intermediate film or the inorganic hard mask intermediate film to which the pattern has been transferred as a mask; (V-8) a step of transferring a pattern to the metal-containing film by dry etching using the organic intermediate film as a mask; and (V-9) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. A pattern forming method comprising the steps of:

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

[10] onto the resist underlayer film on which the pattern has been formed, and then heat-treating the composition to form a metal-containing film, thereby filling spaces between the resist underlayer film patterns with the metal-containing film; (VI-8) a step of etching back the metal-containing film covering the resist underlayer film on which the pattern is formed by a chemical stripper or dry etching to expose an upper surface of the resist underlayer film on which the pattern is formed; (VI-9) a step of removing the silicon-containing resist intermediate film or hard mask intermediate film remaining on the upper surface of the resist underlayer film by dry etching; (VI-10) a step of removing the resist underlayer film on which the pattern is formed and the surface is exposed by dry etching to form a reverse pattern of the original pattern on the metal-containing film; (VI-11) A step of processing the substrate to be processed using the metal-containing film on which the reverse pattern is formed as a mask to form a reverse pattern on the substrate to be processed. 13. A method for forming a tone-reversal pattern comprising:

[0301] The present invention is not limited to the above-described embodiment. The above-described embodiment is merely an example, and anything that has substantially the same configuration as the technical idea described in the claims of the present invention and exhibits similar effects is included in the technical scope of the present invention. [Explanation of symbols]

[0302] 1...substrate to be processed, 2...layer to be processed, 2a...pattern (pattern formed on layer to be processed), 3...metal-containing film, 3a...metal-containing film pattern, 4...silicon-containing resist intermediate film, 4a...silicon-containing resist intermediate film pattern, 5...resist upper layer film, 5a...resist upper layer film pattern, 6...exposed portion, 7...resist underlayer film, 7a...resist underlayer film pattern, 8...metal-containing film, 8a...metal-containing film pattern obtained by inverting the resist underlayer film pattern, 9: underlying substrate having dense lines and spaces; 10: metal-containing film; 11: void.

Claims

1. (A) a metal compound containing at least one metal selected from the group consisting of Ti, Zr, and Hf; (B) a crosslinking agent containing 2 to 4 cyclic ether structures having 2 to 13 carbon atoms in the molecule; (C) a solvent; A composition for forming a metal-containing film, comprising:

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

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

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

5. 4. The metal-containing film-forming composition according to claim 3, wherein X in the formula (1) is any one of the following structures: 【Chemistry 2】 (In the above formula, n is 1 to 5, r is 0 or 1, s is 1 or 2, and R ３ , R ４ are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms which may contain a halogen atom, R ５ is a hydrogen atom, a hydroxyl group, or an alkyl group having 1 to 10 carbon atoms; R ６ , R ７ are each independently a hydrogen atom, a hydroxyl group, or an organic group containing an alkyl group, an alkylene group, or an alkynyl group having 1 to 10 carbon atoms; R ８ is a hydrogen atom, a hydroxyl group, or an organic group containing an alkyl group, alkylene group, or alkynyl group having 1 to 10 carbon atoms, and * represents the bonding site with L. The carbon atom in the aromatic ring of the above formula may have a hydroxyl group, a carboxyl group, an ethenyl group, an ethynyl group, an amino group, a sulfide group, or an alkyl group having 1 to 10 carbon atoms which may contain any of these as a substituent.

6. 2. The metal-containing film-forming composition according to claim 1, wherein the metal compound (A) is derived from a metal compound represented by the following formula (2): 【Chemistry 3】 (In the formula, M is any one of Ti, Zr, and Hf. Ln is independently a monodentate or polydentate ligand having 1 to 30 carbon atoms, and Xn is independently a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, -NR ａ R ｂ R is a hydrolyzable group selected from ａ and R ｂ are each independently a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; a+b=4, and a and b are integers from 0 to 4.

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

8. The metal-containing film-forming composition according to claim 6, characterized in that the (A) metal compound is a reaction product of a compound derived from the metal compound represented by formula (2) with an organic compound having 1 to 30 carbon atoms and containing at least one crosslinking group represented by the following general formulas (a-1) to (a-4), (b-1) to (b-4), (c-1) to (c-3), and (d-1) to (d-2). 【Chemistry 5】 (In the above general formulas (a-1) to (a-4), R ａ are independently a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, q represents 0 or 1, and * represents a bond. 【Chemistry 6】 (In the above general formula, R ｂ are independently a hydrogen atom or a methyl group, which may be the same or different in the same formula; R ｃ is hydrogen, or a substituted or unsubstituted, saturated or unsaturated monovalent organic group having 1 to 20 carbon atoms, a substituted or unsubstituted, aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted, arylalkyl group having 7 to 31 carbon atoms, and * represents a bond. 【Chemistry 7】 (In the above general formulas (c-1) to (c-3), Y １ are independently a divalent organic group having 1 to 20 carbon atoms, R is a hydrogen atom, a substituted or unsubstituted saturated monovalent organic group having 1 to 20 carbon atoms or an unsaturated monovalent 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 ｄ are independently an organic group represented by the following general formula (c-4) which generates one or more hydroxyl groups or carboxyl groups by the action of either or both of an acid and heat, and * represents a bond. 【Chemistry 8】 (In the above general formula (c-4), R ｅ represents an organic group whose protecting group is removed by the action of either acid or heat, or both, and * represents Y 1 It represents the bond with 【Chemistry 9】 (In the formula, R ｆ is a hydrogen atom or an organic group having 1 to 10 carbon atoms, and * indicates a bond.)

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

10. 2. The metal-containing film-forming composition according to claim 1, wherein the solvent (C) is a mixture of one or more organic solvents having a boiling point of less than 180° C. and one or more organic solvents having a boiling point of 180° C. or more.

11. A method for forming a pattern on a workpiece substrate, comprising the steps of: (I-1) A step of forming a metal-containing film by applying the composition for forming a metal-containing film according to any one of claims 1 to 10 onto a substrate to be processed and then subjecting the substrate to a heat treatment; (I-2) forming a resist top layer film on the metal-containing film using a photoresist material; (I-3) a step of pattern-exposing the resist upper layer film and then developing it with a developer to form a pattern on the resist upper layer film; (I-4) a step of transferring a pattern to the metal-containing film by dry etching using the resist top layer film on which the pattern is formed as a mask; and (I-5) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. A pattern forming method comprising the steps of:

12. A method for forming a pattern on a workpiece substrate, comprising the steps of: (II-1) forming a resist underlayer film on a substrate to be processed; (II-2) A step of forming a metal-containing film by applying the composition for forming a metal-containing film according to any one of claims 1 to 10 onto the resist underlayer film and then performing a heat treatment; (II-3) forming a resist top layer film on the metal-containing film using a photoresist material; (II-4) a step of forming a pattern on the resist upper layer film by pattern-exposing the resist upper layer film and then developing the resist upper layer film with a developer; (II-5) a step of transferring a pattern to the metal-containing film by dry etching using the resist top layer film on which the pattern has been formed as a mask; (II-6) a step of transferring a pattern to the resist underlayer film by dry etching using the metal-containing film to which the pattern has been transferred as a mask; (II-7) a step of processing the substrate to be processed using the resist underlayer film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed; A pattern forming method comprising the steps of:

13. A method for forming a pattern on a workpiece substrate, comprising the steps of: (III-1) A step of forming a metal-containing film by applying the composition for forming a metal-containing film according to any one of claims 1 to 10 onto a substrate to be processed and then heat-treating the composition; (III-2) forming a silicon-containing resist intermediate film on the metal-containing film; (III-3) forming a resist upper layer film on the silicon-containing resist intermediate film using a photoresist material; (III-4) a step of pattern-exposing the resist upper layer film and then developing the same with a developer to form a pattern on the resist upper layer film; (III-5) a step of transferring a pattern to the silicon-containing resist intermediate film by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (III-6) A step of transferring a pattern to the metal-containing film by dry etching using the silicon-containing resist intermediate film to which the pattern has been transferred as a mask; and (III-7) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. A pattern forming method comprising the steps of:

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

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

16. A method for forming a pattern on a workpiece substrate, comprising the steps of: (V-1) A step of forming a metal-containing film by applying the composition for forming a metal-containing film according to any one of claims 1 to 10 onto a substrate to be processed and then subjecting the substrate to a heat treatment; (V-2) forming an organic intermediate film on the metal-containing film; (V-3) A step of forming a silicon-containing resist intermediate film or a combination of an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film and an organic thin film on the organic intermediate film; (V-4) forming a resist top layer film on the silicon-containing resist intermediate film or the organic thin film using a photoresist material; (V-5) a step of pattern-exposing the resist upper layer film and then developing the same with a developer to form a pattern on the resist upper layer film; (V-6) a step of transferring a pattern to the silicon-containing resist intermediate film or the organic thin film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film on which the pattern has been formed as a mask; (V-7) A step of transferring a pattern to an organic intermediate film by dry etching using the silicon-containing resist intermediate film or the inorganic hard mask intermediate film to which the pattern has been transferred as a mask; (V-8) A step of transferring a pattern to the metal-containing film by dry etching using the organic intermediate film as a mask; and (V-9) A step of processing the substrate to be processed using the metal-containing film on which the pattern has been formed as a mask to form a pattern on the substrate to be processed. A pattern forming method comprising the steps of:

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

13. A method for forming a tone-reversal pattern comprising:

Images