Composition for forming metal-containing film and patterning process

Abstract

To provide: a composition for forming a metal-containing film having not only excellent dry etching resistance but also high filling / planarizing properties as compared with conventional organic underlayer film materials; and a patterning process using the composition as a resist underlayer film material.SOLUTION: A composition for forming a metal-containing film contains (A) a resin, (B) a metal source, and (C) an organic solvent. The resin (A) contains no phenolic hydroxyl group. The metal source (B) is a salt of a metal selected from Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf and Bi with a monovalent to tetravalent carboxylic acid having 1 to 30 carbon atoms, or a complex of the metal with a β-diketone.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 Art

[0002] With the high integration and high speed of LSIs, the miniaturization of pattern dimensions has been rapidly progressing. Along with this miniaturization, lithography technology has achieved the formation of fine patterns by shortening the wavelength of the light source and appropriately selecting a resist composition for it. At the center has been the positive photoresist composition used as a single layer. This single-layer positive photoresist composition has a skeleton in the resist resin that has etching resistance against dry etching with chlorine-based or fluorine-based gas plasmas, and has a switching mechanism such that the exposed portion dissolves, thereby dissolving the exposed portion to form a pattern, and dry-etching the substrate to be processed using the remaining resist pattern as an etching mask.

[0003] However, when the film thickness of the photoresist film used is directly miniaturized, that is, when the pattern width is made smaller, the resolution performance of the photoresist film deteriorates, and when attempting to develop the photoresist film into a pattern with a developer, the so-called aspect ratio becomes too large, resulting in a problem that pattern collapse occurs. For this reason, the photoresist film has been thinned with the miniaturization of the pattern.

[0004] On one hand, for processing a substrate to be processed, usually, a method of processing the substrate by dry etching using a photoresist film with a pattern formed thereon as an etching mask is employed. However, in reality, there is no dry etching method that can achieve perfect etching selectivity between the photoresist film and the substrate to be processed. Therefore, during the processing of the substrate, the photoresist film is also damaged and collapses, resulting in the problem that the resist pattern cannot be accurately transferred to the substrate to be processed. Thus, with the miniaturization of patterns, higher dry etching resistance has been required for resist compositions. However, on the other hand, in order to improve resolution, resins used in photoresist compositions have been required to have low light absorption at the exposure wavelength. Therefore, as the exposure light has become shorter in wavelength, such as i-line, KrF, and ArF, the resins have also changed from novolak resins, polyhydroxystyrene, to resins having an aliphatic polycyclic skeleton. However, in reality, the etching rate under dry etching conditions during substrate processing has become faster, and recent photoresist compositions with high resolution tend to have weaker etching resistance.

[0005] From this, it becomes necessary to dry-etch the substrate to be processed with a thinner and less etching-resistant photoresist film, and ensuring materials and processes in this processing step has become an urgent task.

[0006] As one method to solve such problems, there is the multilayer resist method. This method involves interposing a resist intermediate film with different etching selectivity from the photoresist film (i.e., the resist upper layer film) between the resist upper layer film and the substrate to be processed. After obtaining a pattern on the resist upper layer film, the resist upper layer film pattern is used as a dry etching mask to transfer the pattern to the resist intermediate film by dry etching, and further, the resist intermediate film is used as a dry etching mask to transfer the pattern to the substrate to be processed by dry etching.

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

[0008] On the other hand, in recent years, the miniaturization of DRAM memories has been accelerating, and there is an increasing need for further improvement in dry etching resistance and a resist underlayer film having excellent embedding characteristics and planarization characteristics. As coating-type organic underlayer film materials having excellent embedding characteristics and planarization characteristics, those described in Patent Document 2, for example, have been reported, but when considering application in advanced generations, there are concerns about dry etching resistance, and the application limit of conventional coating-type organic underlayer film materials is approaching.

[0009] Regarding the above problems, the development using a material containing a metal element in the resist underlayer film has been studied. Patent Document 3 reports that a material using a Ti compound exhibits excellent dry etching resistance against CHF3 / CF4-based gases and CO2 / N2-based gases.

[0010] On the other hand, when using a metal compound for a resist underlayer film, an issue is the embedding property. Although Patent Document 3 does not mention the embedding property, generally, metal oxide compounds have a large thermal shrinkage during baking and induce a significant deterioration in filling property after high-temperature baking. Therefore, there is a concern that they are insufficient as a resist underlayer film material that requires high planarization characteristics, embedding characteristics, and heat resistance. Patent Documents 4 and 5 report that metal compounds modified with specific ligands have excellent embedding properties. However, the baking temperature for the embedding property evaluation carried out is as low as 150°C, and there is a concern that they are insufficient as a resist underlayer film that requires heat resistance (for example, characteristics against heat treatment that may be applied after forming the resist underlayer film).

[0011] In contrast, a composition for forming a metal oxide film in which a high-carbon polymer is added to metal oxide nanoparticles has been proposed (Patent Documents 5 and 6). Patent Document 5 reports an improvement in the embedding property of a metal oxide compound by using metal oxide nanoparticles with a small thermal shrinkage for the metal oxide compound. However, since the film formed using metal nanoparticles has crystallinity, when using nanoparticles for a resist underlayer film material, there is a risk of deteriorating the line width roughness (LWR) of the pattern when etching the substrate to be processed.

[0012] In Patent Documents 7 and 8, resist materials added with metal salts or organometallic complexes have been studied. In these materials, phenolic resins are mentioned to promote the crosslinking of the resist material. However, phenolic hydroxyl groups have problems with stability with metal salts or organometallic complexes. Also, since the resist underlayer film requires properties such as heat resistance, embedding / planarization characteristics, and dry etching resistance, a different material design is required from the above.

Prior Art Documents

Patent Documents

[0013]

Patent Document 1

[0014] The present invention has been made in view of the above circumstances, and provides a composition for forming a metal-containing film having excellent dry etching resistance and high embedding / planarization characteristics with respect to conventional organic underlayer film materials, and a pattern forming method using the composition as a resist underlayer film material. [Means for Solving the Problems]

[0015] In order to solve the above problems, in the present invention, (A) a resin, (B) a metal source, and (C) an organic solvent, a composition for forming a metal-containing film, wherein the resin (A) is a resin containing no phenolic hydroxyl group, and the metal source (B) is a salt of a metal selected from Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi and a monovalent to tetravalent carboxylic acid having 1 to 30 carbon atoms, or a complex of the metal and β-diketones, to provide a composition for forming a metal-containing film.

[0016] Such a composition for forming a metal-containing film can provide a resist underlayer film material that has excellent dry etching resistance, small volume shrinkage during baking, and excellent planarization / embedding characteristics even after high-temperature baking. In addition, since the resin (A) does not contain phenolic hydroxyl groups, a resist underlayer film material with excellent storage stability can be provided.

[0017] Moreover, it is preferable that the resin (A) contains one or more crosslinking groups selected from substituted or unsubstituted vinyl groups, allyl groups, allyloxy groups, ethynyl groups, propargyl groups, propargyloxy groups, epoxy groups, and oxetanyl groups.

[0018] Such a composition for forming a metal-containing film can highly achieve both thermal fluidity and thermosetting properties, and can provide a resist underlayer film material that exhibits more excellent planarization / embedding characteristics.

[0019] Moreover, it is preferable that the resin (A) contains an aromatic ring, an alicyclic hydrocarbon, or a heteroaromatic ring and contains a crosslinking group represented by the following formula (1).

Chemical formula

[0020] Such a composition for forming a metal-containing film can highly achieve both thermal fluidity and thermosetting properties, and can provide a resist underlayer film material that exhibits more excellent planarization / embedding characteristics.

[0021] It is preferable that the (B) metal source is a salt of the metal and a monovalent to tetravalent carboxylic acid having 1 to 30 carbon atoms.

[0022] With respect to a composition for forming a metal-containing film containing such a (B) metal source, a resist underlayer film having more excellent dry etching resistance can be formed. Further, it is preferable from the viewpoints of solvent solubility and availability of raw materials.

[0023] Further, it is preferable that the (B) metal source has a structure represented by the following formula (B-1).

Chemical formula

[0024] With respect to a composition for forming a metal-containing film containing such a (B) metal source, a resist underlayer film having excellent dry etching resistance can be surely formed. Further, it is preferable from the viewpoints of solvent solubility and availability of raw materials.

[0025] Further, it is preferable that the metal of the (B) metal source is Sn.

[0026] With respect to a composition for forming a metal-containing film containing such a (B) metal source, it is preferable because a composition for forming a resist underlayer film that can contribute to improvement in sensitivity while maintaining the LWR of the upper-layer resist can be obtained.

[0027] Further, it is preferable that the (A) resin has at least one structural unit represented by the following general formulas (G-1) to (G-5).

Chemical formula

[0028] For such a composition for forming a metal-containing film, the thermal fluidity of the composition for forming a metal-containing film is further improved, and the embedding property and planarization characteristics with respect to the stepped substrate can be improved. Further, when used directly under the upper layer resist film, a resist lower layer film excellent in adhesion to the upper layer resist film can be formed.

[0029] Further, the composition may further contain one or more of (D) a crosslinking agent, (E) an acid generator, (F) a surfactant, and (G) a pigment.

[0030] Such components can be added to the composition for forming a metal-containing film of the present invention as necessary.

[0031] It is preferable that the organic 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 ((C') high-boiling solvent) having a boiling point of 180°C or higher.

[0032] By imparting fluidity to the composition for forming a metal-containing film by adding a high-boiling solvent to the composition for forming a metal-containing film, it is possible to suppress the occurrence of coating defects due to drying of the composition for forming a metal-containing film.

[0033] Further, in the present invention, there is provided a method for forming a pattern on a substrate to be processed, comprising: (I-1) A step of forming a metal-containing film by applying the above-described composition for forming a metal-containing film on a substrate to be processed and then performing heat treatment; (I-2) A step of forming a resist upper layer film on the metal-containing film using a photoresist material; (I-3) 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 the pattern to the metal-containing film by dry etching using the resist upper layer film on which the pattern is formed as a mask; and (I-5) A step of processing the substrate to be processed using the metal-containing film on which the pattern is formed as a mask to form a pattern on the substrate to be processed A pattern forming method having the above steps is provided.

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

[0035] Further, in the present invention, there is provided a method for forming a pattern on a substrate to be processed, comprising: (II-1) A step of forming a metal-containing film by applying the above-described composition for forming a metal-containing film on a substrate to be processed and then performing heat treatment; (II-2) A step of forming a silicon-containing resist intermediate film on the metal-containing film; (II-3) A step of forming a resist upper layer film on the silicon-containing resist intermediate film using a photoresist material, (II-4) After pattern-exposing the resist upper layer film, developing it with a developer to form a pattern in the resist upper layer film, (II-5) Using the resist upper layer film on which the pattern is formed as a mask, transferring the pattern to the silicon-containing resist intermediate film by dry etching, (II-6) Using the silicon-containing resist intermediate film on which the pattern is transferred as a mask, transferring the pattern to the metal-containing film by dry etching, and (II-7) Using the metal-containing film on which the pattern is formed as a mask to process the substrate to be processed and form a pattern on the substrate to be processed A pattern formation method is provided.

[0036] By the pattern formation method using the above three-layer resist process, a fine pattern can be formed on the workpiece with high precision.

[0037] Also, in the present invention, a method for forming a pattern on a substrate to be processed, (III-1) A step of forming a metal-containing film by applying the above composition for forming a metal-containing film on the substrate to be processed and then performing a heat treatment, (III-2) A step of forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film on the metal-containing film, (III-3) A step of forming an organic thin film on the inorganic hard mask intermediate film, (III-4) A step of forming a resist upper layer film on the organic thin film using a photoresist material, (III-5) After pattern-exposing the resist upper layer film, developing it with a developer to form a pattern in the resist upper layer film, (III-6) Using the resist upper layer film on which the pattern is formed as a mask, transferring the pattern to the organic thin film and the inorganic hard mask intermediate film by dry etching, (III-7) Using the inorganic hard mask intermediate film onto which the pattern has been transferred as a mask, transferring the pattern to the metal-containing film by dry etching, and (III-8) Using the metal-containing film onto which the pattern has been formed as a mask to process the substrate to be processed and forming a pattern on the substrate to be processed provided is a patterning method having these steps.

[0038] By the patterning method using the four-layer resist process, a fine pattern can be formed on the object to be processed with high precision.

[0039] Further, in the present invention, a method for forming a pattern on a substrate to be processed, (IV-1) A step of forming a metal-containing film by applying the above composition for forming a metal-containing film on a substrate to be processed and then performing heat treatment, (IV-2) A step of forming an organic intermediate film on the metal-containing film, (IV-3) A step of forming a combination of a silicon-containing resist intermediate film or an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film and an organic thin film on the organic intermediate film, (IV-4) A step of forming a resist upper layer film using a photoresist material on the silicon-containing resist intermediate film or the organic thin film, (IV-5) After pattern-exposing the resist upper layer film, developing it with a developer to form a pattern on the resist upper layer film, (IV-6) Using the resist upper layer film on which the pattern has been formed as a mask, transferring the pattern to the silicon-containing resist intermediate film or the organic thin film and the inorganic hard mask intermediate film by dry etching, (IV-7) Using the silicon-containing resist intermediate film or the inorganic hard mask intermediate film onto which the pattern has been transferred as a mask, transferring the pattern to the organic intermediate film by dry etching, (IV-8) Using the organic intermediate film as a mask, transferring the pattern to the metal-containing film by dry etching, and (IV-9) 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 To provide a patterning method having the same.

[0040] By the patterning method using the multilayer resist process, a fine pattern can be formed on the object to be processed with high accuracy.

[0041] Further, in the present invention, a method of forming a tone inversion type pattern on a substrate to be processed, (V-1) A step of forming a resist underlayer film on the substrate to be processed, (V-2) A step of forming a combination of a resist intermediate film or an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film and an organic thin film on the resist underlayer film, (V-3) A step of forming a resist upper layer film using a photoresist material on the resist intermediate film or the combination of the inorganic hard mask intermediate film and the organic thin film, (V-4) After pattern exposure of the resist upper layer film, developing with a developer to form a pattern on the resist upper layer film, (V-5) A step of transferring the pattern to the resist intermediate film or the organic thin film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film on which the pattern is formed as a mask, (V-6) A step of transferring the pattern to the resist underlayer film by dry etching using the resist intermediate film or the inorganic hard mask intermediate film on which the pattern is transferred as a mask, (V-7) A step of coating a metal-containing film by applying the above composition for forming a metal-containing film on the resist underlayer film on which the pattern is formed and then performing heat treatment, and filling the spaces between the resist underlayer film patterns with the metal-containing film, (V-8) A step of etching back the metal-containing film covering the resist underlayer film on which the pattern is formed by a chemical stripper or dry etching to expose the upper surface of the resist underlayer film on which the pattern is formed, (V-9) A step of removing the resist intermediate film or the hard mask intermediate film remaining on the upper surface of the resist lower film by dry etching. (V-10) A step of removing the resist lower film on which the pattern with the exposed surface is formed by dry etching to form an inverted pattern of the original pattern made of a metal-containing film. (V-11) A step of processing the substrate to be processed using the metal-containing film on which the inverted pattern is formed as a mask to form an inverted pattern on the substrate to be processed. provided is a patterning method having the above steps.

[0042] By the patterning method according to the above inversion process, a finer pattern can be formed on the object to be processed with higher precision.

[0043] Also, in the step (I-3), it is preferable to perform the pattern exposure using EUV light.

[0044] Also, in the step (II-4), it is preferable to perform the pattern exposure using EUV light.

[0045] Also, in the step (III-5), it is preferable to perform the pattern exposure using EUV light.

[0046] Also, in the step (IV-5), it is preferable to perform the pattern exposure using EUV light.

[0047] Also, in the step (V-4), it is preferable to perform the pattern exposure using EUV light.

[0048] Since the composition for forming a metal-containing film of the present invention contains metal atoms with high light absorption, in EUV lithography, it is possible to form a resist lower film that can contribute to improving the sensitivity while maintaining the LWR of the upper resist.

Effect of the Invention

[0049] For such a composition for forming a metal-containing film, since the metal salt structure decomposes by heat treatment and metal ions are desorbed to form a metal oxide, a resist underlayer film with a high metal content can be provided. Further, since it is a mixture with (A) resin, the volume shrinkage during baking is small, and a resist underlayer film material excellent in planarization / embedding characteristics can be provided even after high-temperature baking. Furthermore, since the above (A) resin does not contain phenolic hydroxyl groups, a composition for forming a metal-containing film with excellent stability can be provided.

[0050] In addition, the resist underlayer film formed using the composition for forming a metal-containing film of the present invention contains a large amount of metal atoms with high light absorption in the film, so it has the characteristic that the sensitization effect by secondary electrons generated during exposure in EUV lithography can be expected. Furthermore, since the above metal atoms have a large atomic weight, they have a high effect of suppressing acid diffusion from the upper-layer resist into the resist underlayer film, and have the characteristic that high sensitivity can be achieved while maintaining the LWR performance originally possessed by the resist upper-layer film.

[0051] Furthermore, since the resist underlayer film can obtain high etching selectivity with respect to organic materials, the formed photoresist pattern can be transferred to a metal-containing resist underlayer film, an organic underlayer film, or a CVD organic hard mask in order using a dry etching process. In particular, in the semiconductor device manufacturing process in recent years where miniaturization is progressing, the film thickness of the photoresist film tends to be reduced in order to prevent pattern collapse after development, which has made pattern transfer to the resist underlayer film difficult. However, when using the composition for forming a metal-containing film of the present invention, even if a thin photoresist film is used as an etching mask, deformation of the photoresist pattern during dry etching can be suppressed, and this pattern can be transferred to the substrate with high accuracy.

Brief Description of the Drawings

[0052]

Figure 1

Figure 2

Figure 3

Figure 4

Mode for Carrying Out the Invention

[0053] As described above, in a fine patterning process using a multilayer resist method, in order to form a resist underlayer film capable of transferring a resist pattern to a substrate to be processed with higher accuracy, there has been a demand for the development of a composition for forming a metal-containing film having excellent embedding properties and flatness, a compound for forming a metal-containing film useful for the composition, and a pattern forming method using the composition.

[0054] The present inventors focused on a metal material that exhibits excellent etching resistance against conventional resist underlayer film materials and conducted intensive studies. On the other hand, conventional metal compounds for forming a resist underlayer film have poor heat resistance and cause rapid volume shrinkage during baking, so it is difficult to fill and planarize the steps of the substrate to be processed after high-temperature baking.

[0055] The present inventors considered that if it is a salt of a metal selected from Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi and a monovalent to tetravalent carboxylic acid having 1 to 30 carbon atoms, or a complex of the metal and β-diketones, the volume shrinkage during baking is small, and by combining with a resin, it is possible to fill the steps of the substrate to be processed without generating voids even after high-temperature baking. Furthermore, the inventors found that if the resin has a structure that does not contain phenolic hydroxyl groups, a composition for forming a metal-containing film having excellent storage stability can be provided, and thus completed the present invention.

[0056] That is, the present invention is a composition for forming a metal-containing film, which contains (A) a resin, (B) a metal source, and (C) an organic solvent, wherein the (A) resin is a resin containing no phenolic hydroxyl group, and the (B) metal source is a salt of a metal selected from Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi and a C1-C30 monovalent to tetravalent carboxylic acid, or a complex of the metal and β-diketones.

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

[0058] <Composition for forming a metal-containing film> The composition for forming a metal-containing film of the present invention is a composition for forming a metal-containing film containing (A) a resin, (B) a metal source, and (C) an organic solvent, wherein the (A) resin is a resin containing no phenolic hydroxyl group, and the (B) metal source is a salt of a metal selected from Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi and a C1-C30 monovalent to tetravalent carboxylic acid, or a complex of the metal and β-diketones.

[0059] <(A) Resin> The (A) resin contained in the composition for forming a metal-containing film of the present invention is a resin containing no phenolic hydroxyl group.

[0060] If it is a composition for forming a metal-containing film containing such a resin, a composition for forming a metal-containing film excellent in storage stability can be provided.

[0061] Furthermore, it is preferable that the (A) resin contains one or more crosslinking groups selected from a substituted or unsubstituted vinyl group, allyl group, allyloxy group, ethynyl group, propargyl group, propargyloxy group, epoxy group, and oxetanyl group.

[0062] By including such a crosslinking group, the thermosetting property of the resin is improved. When this is used in a composition for forming a metal-containing film, volume shrinkage during high-temperature baking can be reduced, and a resist underlayer film material with excellent embedding / planarization characteristics can be provided.

[0063] It is preferable that the resin (A) contains an aromatic ring, an alicyclic hydrocarbon, or a heteroaromatic ring and includes a crosslinking group represented by the following formula (1).

Chemical formula

[0064] In the above formula, R A is a divalent organic group having 1 to 10 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms, and even more preferably a methylene group. R B is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, and from the viewpoints of thermosetting property and fluidity, a hydrogen atom or a structure represented by the following formula (R B -1) is preferable. R C and R D each are preferably 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, more preferably an alkyl group having 1 to 10 carbon atoms, and even more preferably a methyl group or an ethyl group. L is a divalent organic group having 1 to 10 carbon atoms, and a structure represented by the following formula (L-1) is more preferable.

[0065]

Chemical formula

[0066]

Chem.

[0067] ((A) Since the resin contains an aromatic ring, an alicyclic hydrocarbon, or a heteroaromatic ring, the heat resistance of the resin is improved. When this is used in a composition for forming a metal-containing film, volume shrinkage during high-temperature baking can be reduced, and a resist underlayer film material excellent in embedding / planarization characteristics can be provided. Further, by containing the above crosslinking group, the thermosetting property of the resin is improved. When this is used in a composition for forming a metal-containing film, volume shrinkage during high-temperature baking can be further reduced, and a resist underlayer film material excellent in embedding / planarization characteristics can be provided.)

[0068] Examples of the aromatic ring, alicyclic hydrocarbon, or heteroaromatic ring that the (A) resin has include the following structures.

Chem.

[0069] It is preferable that the resin (A) has a ratio Mw / Mn (i.e., dispersity) of weight average molecular weight Mw to number average molecular weight Mn in terms of polystyrene by gel permeation chromatography method within the range of 1.00 ≤ Mw / Mn ≤ 1.25, and more preferably 1.00 ≤ Mw / Mn ≤ 1.10. By definition, for a monomolecular compound, Mw / Mn is 1.00, but due to the separation property of GPC, the measured value may exceed 1.00. Generally, for a polymer having repeating units, it is extremely difficult to approach Mw / Mn = 1.00 unless a special polymerization method is used, and it has a distribution of Mw and Mw / Mn becomes a value exceeding 1. In the present invention, 1.00 ≤ Mw / Mn ≤ 1.10 is defined as an index indicating monodispersity in order to distinguish a monomolecular compound from a polymer.

[0070] If the compound has a dispersity within such a range, the thermal fluidity of the composition for forming a metal-containing film becomes better. Therefore, when this is used in the composition for forming a metal-containing film, a resist underlayer film material excellent in embedding / planarization characteristics can be provided.

[0071] It is preferable that the resin (A) is a polymer having a weight average molecular weight in terms of polystyrene by gel permeation chromatography method of 1,000 to 12,000, and more preferably Mw is 2,000 to 10,000.

[0072] If it is within such a molecular weight range, solubility in an organic solvent can be ensured and sublimates generated during baking can be suppressed. In addition, since the thermal fluidity of the composition for forming a metal-containing film becomes good, when this is used in the composition for forming a metal-containing film, a resist underlayer film material excellent in embedding / planarization characteristics can be provided.

[0073] It is preferable that the resin (A) has at least one structural unit represented by the following general formulas (G-1) to (G-5).

[0074] (Structural units: G-1, G-2, and G-3)

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0075] For a resin having the structural units represented by the above general formulas (G-1), (G-2), and (G-3), since a high-carbon density condensed carbon ring containing a caldo structure is introduced, it is possible to form a resist underlayer film excellent in dry etching resistance and heat resistance.)

[0076] In the above general formulas (G-1), (G-2), and (G-3), the above R a is the above general formula (Z-1), and the above general formula (Z-1) preferably has the structure of the following general formula (2-A).

[0077] [Chemical formula] (* represents the bonding part with an oxygen atom.)

[0078] By having the organic groups represented by the general formulas (G-1), (G-2) and (G-3), particularly the organic group represented by the general formula (2-A), the thermal fluidity can be further improved, and a resist underlayer film excellent in embedding property and planarization property can be formed.

[0079] The resin having the structural units represented by the general formulas (G-1), (G-2) and (G-3) relaxes the intermolecular interaction and imparts solubility in an organic solvent due to the action of the caldo structure introduced into the molecule, thereby improving the film-forming property during the formation of a coating film. In addition, since a plurality of condensed carbon rings with high carbon density are introduced, it is possible to form a resist underlayer film excellent in heat resistance and dry etching resistance.

[0080] The resin having the structural units represented by the general formulas (G-1), (G-2) and (G-3) can be a compound represented by the following general formula (g-1) and / or (g-2) and / or (g-3).

[0081] [Chemical formula] (In the general formulas (g-1) and (g-2), W1, W2, R a , Y, n1, n2 are the same as those described above.)

[0082] [Chemical formula] (In the general formula (g-3), Z1, R a , n4, n5 are the same as those described above.)

[0083] As examples of the resin having the structural units represented by the general formulas (g-1), (g-2) and (g-3), specifically, the following compounds can be exemplified, but are not limited thereto.

[0084]

Chem.

[0085] It is preferable that the resins (g-1), (g-2) and (g-3) have a ratio Mw / Mn (i.e., dispersity) of weight average molecular weight Mw in terms of polystyrene to number average molecular weight Mn by gel permeation chromatography method within the range of 1.00 ≦ Mw / Mn ≦ 1.25, and more preferably 1.00 ≦ Mw / Mn ≦ 1.10.

[0086] If the compound has a dispersity within such a range, the thermal fluidity of the composition for forming a metal-containing film becomes better.

[0087] The resin having the structural units represented by the general formulas (G-1), (G-2) and (G-3) can be a polymer having repeating units represented by the following general formulas (g-4) and / or (g-5) and / or (g-6).

[0088]

Chem.

[0089]

Chem.

[0090] These are polymers obtained using the compounds represented by the above general formulas (g-1), (g-2), and (g-3), and are excellent in dry etching resistance and heat resistance because the above compounds are used. Further, since they are polymers having repeating units instead of monomers, the outgas components are few, and since they are polymers having a molecular weight distribution, the crystallinity is relaxed and an improvement in film formability can be expected.

[0091] L, which is a linking group constituting the repeating units of the above general formulas (g-4), (g-5), and (g-6), is a divalent organic group having 1 to 40 carbon atoms, and specific examples thereof include the following.

[0092] [Chemical formula]

[0093] Furthermore, it is preferable that the linking group L of the above polymer is the following general formula (10). [Chemical formula] (In the above general formula (10), R1 is a hydrogen atom or an organic group containing an aromatic ring having 1 to 20 carbon atoms, and the dashed line represents a bond.)

[0094] Specific examples of the above general formula (10) include the following. Among them, from the viewpoint of easy availability of raw materials, a methylene group, that is, R1 is preferably a hydrogen atom.

[0095] [Chemical formula]

[0096] Furthermore, it is preferable that the weight average molecular weight Mw in terms of polystyrene of the polymer having the repeating structural units represented by the above general formulas (g-4), (g-5), and (g-6) by gel permeation chromatography is 1,000 to 12,000, and more preferably Mw is 2,000 to 10,000.

[0097] Within such a molecular weight range, solubility in an organic solvent can be ensured, and sublimates generated during baking can be suppressed. In addition, the metal-containing film-forming composition will have good thermal fluidity.

[0098] The resin containing the structural units represented by the general formulas (G-1), (G-2), and (G-3) has a high carbon density because it has a skeletal structure containing a caldo structure. Therefore, the metal-containing film-forming composition containing these compounds exhibits high dry etching resistance and excellent heat resistance. In addition, since it contains the organic group represented by the general formula (Z-1) that contributes to the improvement of thermal fluidity, a resist underlayer film excellent in embedding properties and planarization characteristics can be formed. In the case of using the compounds having the structures represented by the general formulas (g-1), (g-2), and (g-3), the thermal fluidity of the metal-containing film-forming composition becomes even better. On the other hand, in the case of a polymer containing the structural units represented by the general formulas (g-4), (g-5), and (g-6), the generation of sublimates during baking can be suppressed, and it is possible to provide a metal-containing film-forming composition excellent in film thickness uniformity. By mixing the compound having the structures represented by the general formulas (g-1), (g-2), and (g-3) with the polymer containing the structural units represented by the general formulas (g-4), (g-5), and (g-6), a metal-containing film-forming composition that meets the required characteristics can be provided.

[0099] (Constituent unit: G-4) [Chemical formula] (In the formula, m3 and m4 represent 1 or 2, and Z is either a single bond or a structure represented by the following general formula (Z-4). R x is either a structure represented by the following general formula (Z-5).) [Chemical formula] (In the formula, * represents a bond, l represents an integer from 0 to 3, and R a ~R feach independently represents an alkyl group having 1 to 10 carbon atoms, which may be substituted with a hydrogen atom or a fluorine atom, a phenyl group, or a phenylethyl group, and R a and R b may combine to form a cyclic compound.) [Chemical formula] (In the formula, * represents the bonding site to the aromatic ring, and Q1 is a linear saturated hydrocarbon group having 1 to 30 carbon atoms, or a structure represented by the following general formula (Z-6).) [Chemical formula] (In the formula, * represents the bonding site to the carbonyl group, R a is the above general formula (Z-1), and R j represents a linear or branched hydrocarbon group having 1 to 10 carbon atoms, a halogen atom, a nitro group, an amino group, a nitrile group, an alkoxycarbonyl group having 1 to 10 carbon atoms, or an alkanoyloxy group having 1 to 10 carbon atoms. h3 and h4 represent the number of substituents on the aromatic ring, each representing an integer from 0 to 7. However, h3 + h4 is 0 or more and 7 or less. h5 represents 0 to 2.)

[0100] From the viewpoints of dry etching resistance and heat resistance, in the above general formula (G-4), Z is preferably either a single bond or a structure represented by the following formula (4A). [Chemical formula] (In the formula, * represents a bond, and l is the same as in the above formula (Z-4).)

[0101] In the above general formula (Z-5), * represents the bonding site to the aromatic ring, and Q1 is a linear saturated hydrocarbon group having 1 to 30 carbon atoms, or a structure represented by the following general formula (Z-6). When Q1 represents a linear hydrocarbon group having 1 to 30 carbon atoms, the methylene group constituting Q1 may be substituted with an oxygen atom or a carbonyl group. From the viewpoints of dry etching resistance and heat resistance, Q1 preferably has a structure represented by the above general formula (Z-6).

[0102] When the general formula (G-4) has an organic group represented by the general formula (Z-1), particularly an organic group represented by the general formula (2-A), the thermal fluidity can be further improved.

[0103] Since the compound containing the structural unit represented by the general formula (G-4) has a structure in which aromatic rings are connected by a single bond or the general formula (Z-4) and thus has a high carbon density, the composition for forming a metal-containing film containing these compounds exhibits high dry etching resistance and excellent heat resistance. Further, as shown by the above formula (Z-4), the linking group Z can be appropriately selected from various linking groups according to the desired performance. In particular, by introducing the structure represented by the above formula (4A) as Z, heat resistance / etching resistance can be imparted without impairing the film-forming property. Also, since it has a highly flexible terminal R x it is possible to form a thick resist underlayer film without generating defects such as cracks despite containing a rigid aromatic ring structure. Furthermore, the terminal R x contains a terminal group Q1 that imparts thermal fluidity, and as the terminal group Q1, a flexible hydrocarbon structure that contributes to the improvement of thermal fluidity and a rigid aromatic ring structure that contributes to etching resistance and heat resistance can be introduced in an arbitrary ratio according to the required performance. As described above, the composition for forming a metal-containing film using these compounds can achieve both film-forming property and heat resistance / etching resistance at a high level, and it is possible to form a thick film according to the required characteristics.

[0104] (Constituent unit: G-5) [Chemical formula] (In the formula, R 1 is a saturated monovalent organic group having 1 to 30 carbon atoms or an unsaturated monovalent organic group having 2 to 30 carbon atoms, X is a divalent organic group having 1 to 30 carbon atoms, R a is the general formula (Z-1), p is an integer from 0 to 5, q1 is an integer from 1 to 6, p + q1 is an integer of 1 or more and 6 or less, and q2 is 0 or 1.)

[0105] In the above general formula (G-5), examples of the divalent organic group having 1 to 30 carbon atoms represented by X include alkane diyl groups such as methylene group, ethanediyl group, propanediyl group, butanediyl group, pentanediyl group, hexanediyl group, octanediyl group, decanediyl group, etc., cyclopropanediyl group, cyclobutanediyl group, cyclopentanediyl group, cyclohexanediyl group, cycloheptanediyl group, cyclooctanediyl group, cyclodecanediyl group, methylcyclohexanediyl group, ethylcyclohexanediyl group, etc., monocyclic cycloalkane diyl groups, bicyclo[2.2.1]heptane diyl group, bicyclo[2.2.2]octane diyl group, tricyclo[5.2.1.0 2,6 decane diyl group (dicyclopentylene group), tricyclo[3.3.1.1 3,7 decane diyl group, tetracyclo[6.2.1.1 3,6 .0 2,7 dodecane diyl group, adamantane diyl group, etc., polycyclic cycloalkane diyl groups, arene diyl groups such as phenylene group, naphthylene group, etc.

[0106] Also, X may be an alkanediyl oxy group or a cycloalkanediyl oxy group. Examples of the alkanediyl oxy group represented by the above X include groups formed by combining the above alkanediyl group and an oxygen atom. Examples of the cycloalkanediyl oxy group represented by the above X include groups formed by combining the above cycloalkanediyl group and an oxygen atom.

[0107] Some or all of the hydrogen atoms of the above alkanediyl group, cycloalkanediyl group, alkanediyl oxy group, cycloalkanediyl oxy group, and arene diyl group may be substituted, and examples of the substituent include groups similar to the examples of the substituent that the organic group represented by the above R a may have.

[0108] Examples of the organic group represented by the above X include groups represented by the following formula.

Chemical formula

[0109] As the above X, from the viewpoint of raw material availability, preferably a methylene group can be mentioned.

[0110] As the resin having the structural unit represented by the above general formula (G-5), specifically, the following can be exemplified.

[0111] [Chemical formula]

[0112] [Chemical formula] (In the above formula, R a is the same as above.)

[0113] Since the polymer containing the structural unit represented by the above general formula (G-5) has a structure in which aromatic rings are connected by an organic group (X), it has a high carbon density. Therefore, the composition for forming a metal-containing film containing these resins exhibits high dry etching resistance and excellent heat resistance, and thus can form a resist underlayer film with less sublimation products. Furthermore, since the organic group having the structure represented by the above general formula (Z-1), which contributes to the improvement of thermal fluidity, is directly bonded to the aromatic ring, which is the mother nucleus structure of the resin, via an oxygen atom, the composition for forming a metal-containing film using these polymers can achieve high-dimensional compatibility between film-forming properties and heat resistance / etching resistance. In addition, since the aromatic ring structure of the mother nucleus is not too rigid and forms a repeating structure via the organic group (X) as a linking group, it is possible to form a thick resist underlayer film without generating defects such as cracks. As described above, the composition for forming a metal-containing film using these polymers can achieve high-dimensional compatibility between film-forming properties and heat resistance / etching resistance, and can form a thick film according to the required characteristics.

[0114] In the composition for forming a metal-containing film of the present invention, the blending amount of (A) resin is not particularly limited. For example, it is 0.1 to 50 parts by mass, preferably 1 to 20 parts by mass, more preferably 2 to 10 parts by mass with respect to 100 parts by mass of the (C) organic solvent described below.

[0115] <(B) Metal source> The (B) metal source contained in the composition for forming a metal-containing film of the present invention is a salt of a metal selected from Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi and a monovalent to tetravalent carboxylic acid having 1 to 30 carbon atoms, or a complex of the metal and β-diketones.

[0116] Preferred carboxylates can be exemplified as follows.

Chemical formula

[0117] The carboxylate ions for forming the carboxylate salt in the above general formula are specifically exemplified as follows.

[0118]

Chemical formula

[0119]

Chemical formula

[0120]

Chemical formula

[0121]

Chemical formula

[0122]

Chemical formula

[0123]

Chemical formula

[0124]

Chemical formula

[0125]

Chemical formula

[0126] [Chemical formula]

[0127] [Chemical formula]

[0128] [Chemical formula]

[0129] The carboxylate ions for forming the above carboxylate salt are preferably those in which the larger the number of carbon atoms in the carboxylic acid, the more easily soluble in the organic solvent. Also, if the number of carbon atoms in the carboxylic acid is not too large, the amount of outgas components when the composition for forming the metal-containing film is spin-coated is reduced, the shrinkage amount when the resist film is formed is also small, and the embedding property is good. From the above viewpoints, the carboxylate ions preferably have a linear or branched alkyl group having 3 to 10 carbon atoms.

[0130] Preferred β-diketone complexes can be exemplified as follows.

[0131] [Chemical formula] (In the formula, R 1 , R 2 are the same or different linear, branched or cyclic alkyl groups having 1 to 20 carbon atoms, alkenyl groups having 2 to 20 carbon atoms, alkynyl groups having 2 to 20 carbon atoms, or aryl groups having 6 to 20 carbon atoms, and these may have a hydroxy group, an alkoxy group, an ether group, an ester group, an amino group, an amide group, a sulfonic acid ester group, a halogen atom, a cyano group, a nitro group, a carbonate group, a carbamate group, a thiol group, a sulfide group, a thioketone group, or a heteroaromatic ring.)

[0132] The β-diketones in the above general formula are substituted or unsubstituted acetylacetones, and specifically, they are exemplified as follows.

[0133] [Chemical]

[0134] [Chemical]

[0135] [Chemical]

[0136] [Chemical]

[0137] [Chemical]

[0138] [Chemical]

[0139] R 1 and R 2 are generally the same β-diketones, but may be different as described in JP-A-2004-175755. R 1 and R 2 are both methyl groups, and acetylacetone is the most common, but it has the drawback of poor solubility in organic solvents. R 1 and R 2 The total number of carbon atoms is preferably 3 or more, more preferably 4 or more.

[0140] The hydrogen atoms of acetylacetone are substituted, and the larger the number of carbon atoms in the substituent, the easier it is to dissolve in an organic solvent, which is preferable. On the other hand, if the number of carbon atoms in the substituent is not too large, the shrinkage amount when forming a resist film is reduced, and the embedding property becomes good.

[0141] Acetylacetone forms a complex with a metal by enolization as shown below.

Chemical formula

[0142] The (B) metal source used in the composition for forming a metal-containing film of the present invention is preferably a salt of a metal selected from Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi and a monovalent to tetravalent carboxylic acid having 1 to 30 carbon atoms. More preferably, it has a structure represented by the following formula (B-1).

Chemical formula

[0143] The content of the (B) metal source in the composition for forming a metal-containing film is preferably 5 to 1900 parts by mass, more preferably 10 to 900 parts by mass, still more preferably 30 to 300 parts by mass, and extremely preferably 50 to 200 parts by mass with respect to 100 parts by mass of the (A) resin. When the content of the (A) resin is large, the thermal fluidity and heat resistance of the composition for forming a metal-containing film are further improved, and a resist underlayer film excellent in embedding properties and planarization characteristics can be formed. When the content of the (B) metal source is large, a resist underlayer film having extremely excellent dry etching resistance can be formed. In addition, in EUV lithography, the contribution ratio of the metal-containing film to the improvement of the exposure sensitivity of the resist upper layer film becomes large, which is preferable. These can be appropriately adjusted according to the required properties required when used in the composition for forming a metal-containing film.

[0144] From the viewpoint of improving the exposure sensitivity of the resist upper layer film in EUV lithography, M in the above formula (B-1) is more preferably Ti, Hf, Sn, or Bi, and still more preferably Sn.

[0145] <(C) Organic solvent> As the (C) organic solvent that can be used in the composition for forming a metal-containing film of the present invention, there is no particular limitation as long as it can dissolve or disperse the above-mentioned (A) resin, (B) metal source, and, when included, the following (D) crosslinking agent, (E) acid generator, (F) surfactant, and (G) dye, and other additives.

[0146] Specifically, for example, the organic solvents described in paragraphs

[0091] to

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

[0147] The blending amount of the organic solvent is preferably 200 to 10,000 parts, more preferably 250 to 5,000 parts, per 100 parts by mass of the (B) metal source.

[0148] <(C’) High-boiling solvent> In the composition for forming a metal-containing film of the present invention, the (C) organic solvent may contain a (C’) high-boiling solvent.

[0149] (C’) The high-boiling solvent can be one or more organic solvents having a boiling point of 180 degrees (°C) or higher.

[0150] For example, as the (C) organic solvent, 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 ((C’) high-boiling solvent) may be used.

[0151] (C’) As the high-boiling solvent, there are no particular restrictions as long as it can dissolve or disperse each component of the composition for forming a metal-containing film of the present invention, and examples include hydrocarbons, alcohols, ketones, esters, ethers, chlorinated solvents, etc. Specific examples include 1-octanol, 2-ethylhexanol, 1-nonanol, 1-decanol, 1-undecanol, ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, 2,4-pentanediol, 2-methyl-2,4-pentanediol, 2,5-hexanediol, 2,4-heptanediol, 2-ethyl-1,3 - hexanediol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, glycerin, n-nonyl acetate, monohexyl ether, ethylene glycol mono-2-ethylhexyl ether, ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, diethylene glycol monoethyl ether, diethylene glycol monoisopropyl ether, diethylene glycol mono-n-butyl ether, diethylene glycol monoisobutyl ether, diethylene glycol monohexyl ether, diethylene glycol monophenyl ether, diethylene glycol monobenzyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol monomethyl ether, triethylene glycol - n-butyl ether, triethylene glycol butyl methyl ether, tetraethylene glycol dimethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-n-butyl ether, tripropylene glycol dimethyl ether, tripropylene glycol monomethyl ether, tripropylene glycol mono-n-propyl ether, tripropylene glycol mono-n-butyl ether, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, triacetin, propylene glycol diacetate, dipropylene glycol methyl-n-propyl ether, dipropylene glycol methyl ether acetate, 1,4 - butanediol diacetate, 1,3 - butylene glycol diacetate, 1,Examples thereof include 6-hexanediol diacetate, triethylene glycol diacetate, γ-butyrolactone, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, dihexyl malonate, diethyl succinate, dipropyl succinate, dibutyl succinate, dihexyl succinate, dimethyl adipate, diethyl adipate, dibutyl adipate, triethanolamine, etc., and these may be used alone or in combination.

[0152] (C’) The high-boiling solvent may be appropriately selected from the above-mentioned ones, etc., according to the temperature for heat-treating the composition for forming a metal-containing film of the present invention. The boiling point of the high-boiling solvent is preferably 180°C to 300°C, and more preferably 200°C to 300°C. With such a boiling point, there is no fear that the volatilization during baking (heat treatment) will become too fast, so it is possible to suppress the occurrence of defects caused by drying during film formation. Also, with such a boiling point, it will not remain in the film without volatilizing even after baking, so there is no fear of adversely affecting the film physical properties such as etching resistance.

[0153] Also, when using (C’) the high-boiling solvent, the blending amount is preferably 1 to 30 parts by mass with respect to 100 parts by mass of the organic solvent having a boiling point of less than 180°C. With such a blending amount, sufficient heat fluidity can be imparted during baking, and it will not remain in the film and lead to deterioration of film physical properties such as etching resistance, so it is preferable.

[0154] <Other components> The composition for forming a metal-containing film may contain at least one or more of (D) a crosslinking agent, (E) an acid generator, (F) a surfactant, and (G) a pigment, if necessary.

[0155] Hereinafter, components that can be included in the composition for forming a metal-containing film of the present invention, other than the above-mentioned (A) resin, (B) metal source, and (C) organic solvent, will be described.

[0156] [(D) Crosslinking agent] In addition, in order to enhance the curability and further suppress the intermixing with the resist upper layer film, a (D) crosslinking agent can also be added to the composition for forming a metal-containing film of the present invention.

[0157] The crosslinking agent is not particularly limited, and various known types of crosslinking agents can be widely used. As an example, melamine-based crosslinking agents, 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 epoxy-based crosslinking agents can be exemplified.

[0158] The above (D) crosslinking agent can be used alone or in combination of two or more. When adding the crosslinking agent, the addition amount is preferably 5 to 100 parts, more preferably 10 to 50 parts, based on 100 parts of the above (A) resin. If the addition amount is 5 parts or more, sufficient curability can be exhibited, and intermixing with the resist upper layer film can be suppressed. On the other hand, if the addition amount is 50 parts or less, there is no risk of deterioration of dry etching resistance due to a low ratio of the (B) metal source in the composition.

[0159] From the viewpoint of more stably existing the (B) metal source, it is preferable that the (D) crosslinking agent does not contain a hydroxyl group.

[0160] Specific examples of the melamine-based crosslinking agent include hexamethoxymethylated melamine, hexabutoxymethylated melamine, their alkoxy and / or hydroxy-substituted products, and their partial self-condensates.

[0161] Specific examples of the glycoluril-based crosslinking agent include tetramethoxymethylated glycoluril, tetrabutoxymethylated glycoluril, their alkoxy and / or hydroxy-substituted products, and their partial self-condensates.

[0162] As benzoguanamine-based crosslinking agents, specifically, tetramethoxymethylated benzoguanamine, tetrabutoxymethylated benzoguanamine, their alkoxy and / or hydroxy-substituted derivatives, and their partial self-condensates can be exemplified.

[0163] As urea-based crosslinking agents, specifically, dimethoxymethylated dimethoxyethyleneurea, its alkoxy and / or hydroxy-substituted derivatives, and their partial self-condensates can be exemplified.

[0164] As β-hydroxyalkylamide-based crosslinking agents, specifically, N,N,N’,N’-tetra(2-hydroxyethyl)adipic acid amide can be exemplified.

[0165] As isocyanurate-based crosslinking agents, specifically, triglycidyl isocyanurate, triallyl isocyanurate can be exemplified.

[0166] As aziridine-based crosslinking agents, specifically, 4,4’-bis(ethyleneiminocarbonylamino)diphenylmethane, 2,2-bishydroxymethylbutanol-tris[3-(1-aziridinyl)propionate] can be exemplified.

[0167] As oxazoline-based crosslinking agents, specifically, 2,2’-isopropylidene bis(4-benzyl-2-oxazoline), 2,2’-isopropylidene bis(4-phenyl-2-oxazoline), 2,2’-isopropylidene bis(4-phenyl-2-oxazoline), 2,2’-methylene bis 4,5-diphenyl-2-oxazoline, 2,2’-methylene bis-4-phenyl-2-oxazoline, 2,2’-methylene bis-4-tert butyl-2-oxazoline, 2,2’-bis(2-oxazoline), 1,3-phenylene bis(2-oxazoline), 1,4-phenylene bis(2-oxazoline), 2-isopropenyl oxazoline copolymer can be exemplified.

[0168] Specific examples of the epoxy crosslinking agent include diglycidyl ether, ethylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,4-cyclohexanedimethanol diglycidyl ether, poly(glycidyl methacrylate), trimethylolethane triglycidyl ether, trimethylolpropane triglycidyl ether, and pentaerythritol tetraglycidyl ether.

[0169] Examples of the epoxy crosslinking agent and the oxetane crosslinking agent include, but are not limited to, those shown below.

Chemical formula

[0170] Although the above compounds are commercially available, the epoxy crosslinking agent and the oxetane crosslinking agent can also be obtained by reacting a hydroxyl group with epibromohydrin, 3-bromomethyloxetane, etc. as shown in the following formula. In the following formula, R5 is a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms and being saturated or having 2 to 20 carbon atoms and being unsaturated, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted arylalkyl group having 7 to 31 carbon atoms. Also, it is possible to leave some hydroxyl groups unreacted. At this time, it is preferable that the number of epoxy + oxetane > the number of hydroxyl groups, and more preferably the number of epoxy + oxetane > 2 times the number of hydroxyl groups.

[0171] Also, the content of these compounds is preferably 5 to 100 parts by mass, more preferably 10 to 50 parts by mass, based on 100 parts by mass of the metal source (B).

[0172]

Chemical formula

[0173] Specific examples of the compound having a hydroxyl group that can be used in the above reaction include, but are not limited to, the following.

[0174] [Chemical formula]

[0175] <(E) Acid generator> In the composition for forming a metal-containing film of the present invention, an acid generator can be added to further promote the thermal decomposition reaction of the above (B) metal source. Acid generators include those that generate acid by thermal decomposition and those that generate acid by light irradiation, and any of them can be added. Specifically, the materials described in paragraphs

[0061] to

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

[0176] The above acid generator can be used alone or in combination of two or more. When adding an acid generator, the addition amount is preferably 0.05 to 50 parts, more preferably 0.1 to 10 parts, based on 100 parts by mass of the above (B) metal source.

[0177] [(F) Surfactant] In the composition for forming a metal-containing film of the present invention, an (E) surfactant can be added to improve the coatability in spin coating. As the surfactant, for example, those described in

[0142] to

[0147] of JP-A-2009-269953 can be used. When adding a surfactant, the addition amount is preferably 0.01 to 10 parts, more preferably 0.05 to 5 parts, based on 100 parts by mass of the above (B) metal source.

[0178] [(H) Dye] In addition, in order to further improve the resolution during patterning of multilayer lithography, a (H) dye can be added to the composition for forming a metal-containing film of the present invention. The dye is not particularly limited as long as it is a compound having appropriate absorption at the exposure wavelength, and various known compounds can be widely used. As an example, benzenes, naphthalenes, anthracenes, phenanthrenes, pyrenes, isocyanuric acids, and triazines can be exemplified. When adding the dye, the addition amount is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, based on 100 parts by mass of the above (B) metal source.

[0179] Furthermore, a basic compound for improving storage stability can be added to the composition for forming a metal-containing film of the present invention. The basic compound serves as a quencher for acid to prevent the acid generated in a trace amount from the acid generator from promoting the crosslinking reaction. Specific examples of such basic compounds include those described in paragraphs (0086) to (0090) of JP-A-2007-199653.

[0180] In addition to the above, additives for further improving the embedding / planarization characteristics may be added to the composition for forming a metal-containing film of the present invention. The above additives are not particularly limited as long as they impart embedding / planarization characteristics. For example, polyethylene glycol, a liquid additive having a polypropylene glycol structure, or a thermally decomposable polymer having a weight loss rate of 40% by mass or more and a weight average molecular weight of 300 to 200,000 between 30°C and 250°C is preferably used. This thermally decomposable polymer preferably contains a repeating unit having an acetal structure represented by the following general formulas (DP1) and (DP1a).

[0181]

Chemical formula

[0182] [Chemical formula] (In the formula, R 6a is an alkyl group having 1 to 4 carbon atoms. Y a is a saturated or unsaturated divalent hydrocarbon group having 4 to 10 carbon atoms, and may have an ether bond. n represents the average number of repeating units and is 3 to 500.)

[0183] <Method for forming metal-containing film> In the present invention, a method for forming a filling film that functions as a resist underlayer film of a multilayer resist film used in lithography is provided by using the above-described composition for forming a metal-containing film.

[0184] In the method for forming a metal-containing film using the composition for forming a metal-containing film of the present invention, the above-described composition for forming a metal-containing film is coated on a substrate to be processed by a spin coating method or the like. By using a spin coating method or the like, good planarization characteristics 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. The baking is preferably performed in the range of 100°C or higher and 600°C or lower, for 10 to 600 seconds, more preferably in the range of 200°C or higher and 500°C or lower, for 10 to 300 seconds. Considering the influence on device damage and wafer deformation, the upper limit of the heating temperature in the wafer process of lithography is preferably 600°C or lower, more preferably 500°C or lower.

[0185] Also, in the method for forming a metal-containing film using the composition for forming a metal-containing film of the present invention, the composition for forming a metal-containing film of the present invention is coated on a substrate to be processed by the spin coating method or the like as described above, and the composition for forming a metal-containing film is fired and cured in an atmosphere having an oxygen concentration of 0.1% by volume or higher and 21% by volume or lower to form a metal-containing film.

[0186] By firing the composition for forming a metal-containing film of the present invention in such an oxygen atmosphere, a sufficiently cured film can be obtained. As the atmosphere during baking, air may be used, but it is preferable to enclose an inert gas such as N2, Ar, or He to reduce oxygen in order to prevent oxidation of the metal-containing film. To prevent oxidation, it is necessary to control the oxygen concentration, preferably 1000 ppm or less, more preferably 100 ppm or less (by volume). Preventing oxidation of the metal-containing film during baking is preferable because it does not increase absorption or reduce etching resistance.

[0187] <Pattern formation method> Further, in the present invention, as a pattern formation method by a two-layer resist process using the composition for forming a metal-containing film, (I-1) A step of forming a metal-containing film by applying the composition for forming a metal-containing film of the present invention on a substrate to be processed and then performing heat treatment, (I-2) A step of forming a resist upper layer film on the metal-containing film using a photoresist material, (I-3) A step of forming a pattern in the resist upper layer film by subjecting the resist upper layer film to pattern exposure and then developing it with a developer, (I-4) A step of transferring the pattern to the metal-containing film by dry etching using the resist upper layer film having the pattern as a mask, and (I-5) A step of processing the substrate to be processed using the metal-containing film having the pattern as a mask to form a pattern on the substrate to be processed A pattern formation method having the above steps is provided.

[0188] Since the resist upper layer film of the two-layer resist process exhibits etching resistance to chlorine-based gases, in the two-layer resist process, it is preferable to perform dry etching of the metal-containing film using the resist upper layer film as a mask with an etching gas mainly composed of a chlorine-based gas.

[0189] In order to ensure the adhesion to the resist upper layer film, an adhesion film may be formed between the resist upper layer film and the metal-containing film of the present invention. As the adhesion film, an organic film or a silicon-containing film containing polysiloxane can be used.

[0190] The pattern formation method by a resist process using the composition for forming a metal-containing film of the present invention is useful for improving the exposure sensitivity of the resist upper layer film. Therefore, it is preferably used as a lower layer film close to the resist upper layer film, and more preferably used immediately below the resist upper layer film. When an adhesion film is used between the resist upper layer film and the metal-containing film, the film thickness of the adhesion film is preferably 20 nm or less, more preferably 15 nm or less, and even more preferably 10 nm or less. The thinner the film thickness of the adhesion film, the greater the contribution of the metal-containing film to the improvement of the exposure sensitivity of the resist upper layer film, which is preferable.

[0191] Further, in the present invention, as a pattern formation method by a three-layer resist process using such a composition for forming a metal-containing film, (II-1) A step of forming a metal-containing film by applying the composition for forming a metal-containing film of the present invention on a substrate to be processed and then performing heat treatment, (II-2) A step of forming a silicon-containing resist intermediate film on the metal-containing film, (II-3) A step of forming a resist upper layer film using a photoresist material on the silicon-containing resist intermediate film, (II-4) A step of performing pattern exposure on the resist upper layer film and then developing with a developer to form a pattern on the resist upper layer film, (II-5) A step of transferring the pattern to the silicon-containing resist intermediate film by dry etching using the resist upper layer film having the pattern as a mask, (II-6) A step of transferring the pattern to the metal-containing film by dry etching using the silicon-containing resist intermediate film having the pattern transferred thereto as a mask, and (II-7) A step of processing the substrate to be processed using the metal-containing film having the pattern formed thereon as a mask to form a pattern on the substrate to be processed To provide a pattern forming method having the same.

[0192]

[0193]

[0194] In the above three-layer resist process, since the silicon-containing resist intermediate film shows etching resistance to chlorine-based gas, in the above three-layer resist process, it is preferable to perform dry etching of the metal-containing film using the silicon-containing resist intermediate film as a mask with an etching gas mainly composed of chlorine-based gas. As the silicon-containing resist intermediate film of the above three-layer resist process, a polysiloxane-based intermediate film is also preferably used. By giving the silicon-containing resist intermediate film an antireflection effect, reflection can be suppressed. Particularly for 193 nm exposure, when a material with a high etching selectivity with the substrate and containing many aromatic groups as an organic film is used, the k value becomes high and the substrate reflection becomes high. However, by giving absorption such that the k value becomes appropriate as the silicon-containing resist intermediate film, it becomes possible to suppress reflection and the substrate reflection can be made 0.5% or less. As the silicon-containing resist intermediate film having an antireflection effect, polysiloxane having an anthracene pendant for 248 nm and 157 nm exposure and a phenyl group or an absorbing group having a silicon-silicon bond pendant and crosslinking with acid or heat is preferably used for 193 nm exposure.In addition, in the present invention, as a pattern formation method by a four-layer resist process using such a composition for forming a metal-containing film, a metal-containing film is formed on a substrate to be processed using the composition for forming a metal-containing film, a silicon-containing resist intermediate film is formed on the metal-containing film using a silicon-containing resist intermediate film material, an organic antireflection film (BARC) or an adhesion film is formed on the silicon-containing resist intermediate film, a resist upper layer film is formed on the BARC or the adhesion film using a photoresist material, after the resist upper layer film is pattern-exposed, it is developed with a developer to form a pattern in the resist upper layer film, using the resist upper layer film in which the pattern is formed as a mask, the pattern is transferred to the BARC or the adhesion film and the silicon-containing resist intermediate film by dry etching, using the silicon-containing resist intermediate film in which the pattern is transferred as a mask, the pattern is transferred to the metal-containing film by dry etching, and using the metal-containing film in which the pattern is formed as a mask, the substrate to be processed is processed to form a pattern in the substrate to be processed, thereby providing a pattern formation method.

[0195] Alternatively, an inorganic hard mask may be formed instead of the silicon-containing resist lower layer film. In this case, at least a metal-containing film is formed on the object to be processed using the composition for forming a metal-containing film of the present invention, an inorganic hard mask selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film is formed on the metal-containing film, a resist upper layer film is formed on the inorganic hard mask using a photoresist composition, a circuit pattern is formed in the resist upper layer film, the inorganic hard mask is etched using the resist upper layer film in which the pattern is formed as a mask, the metal-containing film is etched using the inorganic hard mask in which the pattern is formed as a mask, and further, the object to be processed is etched using the metal-containing film in which the pattern is formed as a mask to form a pattern in the object to be processed, whereby a semiconductor device circuit pattern can be formed on the substrate.

[0196] As described above, when forming an inorganic hard mask on a metal-containing film, a silicon oxide film, a silicon nitride film, and a silicon oxynitride film (SiON film) can be formed by a CVD method, an ALD method, or the like. For example, as a method for forming a silicon nitride film, it is described in JP-A-2002-334869 and WO 2004 / 066377. The film thickness of the inorganic hard mask is preferably 5 to 200 nm, more preferably 10 to 100 nm. Further, as the inorganic hard mask, a SiON film having a high effect as an antireflection film is most preferably used. Since the substrate temperature when forming the SiON film is 300 to 500 °C, the metal-containing film needs to withstand a temperature of 300 to 500 °C. The composition for forming a metal-containing film used in the present invention has high heat resistance and can withstand a high temperature of 300 °C to 500 °C. Therefore, a combination of an inorganic hard mask formed by a CVD method or an ALD method and a metal-containing film formed by a spin coating method is possible.

[0197] As described above, a photoresist film may be formed as a resist upper layer film on the inorganic hard mask. However, an organic antireflection film (BARC) or an adhesion film may be spin-coated on the inorganic hard mask, and a photoresist film may be formed thereon. In particular, when a SiON film is used as the inorganic hard mask, it is possible to suppress reflection even in immersion lithography with a high NA exceeding 1.0 by a two-layer antireflection film of the SiON film and BARC. Another merit of forming BARC is that it has an effect of reducing the pulling of the photoresist pattern directly above the SiON film.

[0198] In the above pattern formation method, the resist upper layer film may be either positive or negative, and the same photoresist composition as that usually used can be used. Further, 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 with the above photoresist composition, either a spin coating method or a vapor deposition treatment method by CVD or ALD may be used.

[0199] When forming the resist upper layer film by the spin coating method, pre-baking is performed after resist coating, and a range of 60 to 180 °C for 10 to 300 seconds is preferable. Thereafter, exposure is performed according to a conventional method, post-exposure bake (PEB), and development are performed to obtain a resist pattern. The thickness of the resist upper layer film is not particularly limited, but 10 to 500 nm, particularly 20 to 400 nm is preferable.

[0200] When forming the resist upper layer film by vapor deposition treatment by CVD or ALD, the resist composition is an EUV photosensitive metal oxide film, and the metal is selected from Sn, Zr, Hf, Ti, Bi, Sb, etc., and among them, Sn having excellent EUV photosensitivity is preferable. The metal oxide-containing film may be a photosensitive organometallic oxide film such as an organotin oxide (for example, haloalkyl Sn, alkoxyalkyl Sn, or amidoalkyl Sn). Some specific examples of suitable precursors include trimethyltin chloride, dimethylditin dichloride, methyltin trichloride, tris(dimethylamino)methyltin(IV), and (dimethylamino)trimethyltin(IV).

[0201] The metal oxide film may be deposited by PECVD or PEALD, for example, using a Lam Vector (registered trademark) tool. In the ALD example, the Sn oxide precursor is separated from the O precursor / plasma. The deposition temperature is preferably in the range of 50 °C to 600 °C. The deposition pressure is preferably between 100 and 6000 mTorr. The flow rate of the precursor liquid of the metal oxide-containing film (for example, the organotin oxide precursor) may be 0.01 to 10 cmm, and the gas flow rate (CO2, CO, Ar, N2) may be 100 to 10000 sccm. The plasma power may be 200 to 1000 W per 300 mm wafer station using high-frequency plasma (for example, 13.56 MHz, 27.1 MHz, or a higher frequency). The deposition thickness is preferably 100 to 2000 Å.

[0202] As the exposure light, high-energy rays with a wavelength of 300 nm or less can be mentioned, specifically, excimer lasers of 248 nm, 193 nm, and 157 nm, soft X-rays of 3 to 20 nm, electron beams, X-rays, etc.

[0203] As the method for forming a pattern on the resist upper layer film, a pattern can be formed by photolithography with a wavelength of 5 nm or more and 300 nm or less, direct drawing by an electron beam, nanoimprinting, or a combination thereof. In the present invention, EUV light is most preferable.

[0204] In addition, it is preferable that the development method in the pattern formation method is development with an alkali or development with an organic solvent.

[0205] Next, etching is performed using the obtained resist pattern as a mask. For the etching of the silicon-containing resist intermediate film and the inorganic hard mask in the three-layer resist process, an upper layer resist pattern is used as a mask and performed using a fluorocarbon-based gas. Thereby, a silicon-containing resist intermediate film pattern and an inorganic hard mask pattern are formed.

[0206] Next, using the obtained silicon-containing resist intermediate film pattern and inorganic hard mask pattern as a mask, etching of the metal-containing film is performed. The etching of the metal-containing film is preferably performed using an etching gas mainly composed of a chlorine-based gas.

[0207] Etching of the next workpiece can also be performed by a conventional method. For example, if the workpiece is SiO2, SiN, or a silica-based low dielectric constant insulating film, etching mainly using a fluorocarbon-based gas is performed. When the substrate is etched with a fluorocarbon-based gas, the silicon-containing resist intermediate film pattern in the three-layer resist process is peeled off simultaneously with the substrate processing.

[0208] The metal-containing film obtained by the composition for forming a metal-containing film of the present invention is characterized by excellent etching resistance during etching of these workpieces.

[0209] Note that the workpiece (workpiece substrate) is not particularly limited, and substrates such as Si, α-Si, p-Si, SiO2, SiN, SiON, W, TiN, Al, etc., or those with a processed layer formed on the substrate are used. As the processed layer, various Low-k films such as Si, SiO2, SiON, SiN, p-Si, α-Si, W, W-Si, Al, Cu, Al-Si, etc., and their stopper films are used, and they can usually be formed with a thickness of 50 to 10,000 nm, particularly 100 to 5,000 nm. When forming the processed layer, the substrate and the processed layer are made of different materials.

[0210] Here, an example of the pattern formation method by the three-layer resist method of the present invention is shown in FIGS. 1(A) to (F). In the case of the three-layer resist method, as shown in FIG. 1(A), after forming a metal-containing film 3 on the processed layer 2 formed on the workpiece substrate 1 using the composition for forming a metal-containing film of the present invention, a silicon-containing resist intermediate film 4 is formed, and a resist upper layer film 5 is formed thereon. Next, as shown in FIG. 1(B), the exposed portion 6 of the resist upper layer film 5 is exposed, and PEB (post-exposure bake) is performed. Next, as shown in FIG. 1(C), development is performed to form a resist upper layer film pattern 5a. Next, as shown in FIG. 1(D), using the resist upper layer film pattern 5a as a mask, the silicon-containing resist intermediate film 4 is dry-etched using a fluorocarbon gas to form a silicon-containing resist intermediate film pattern 4a. Next, as shown in FIG. 1(E), after removing the resist upper layer film pattern 5a, using the silicon-containing resist intermediate film pattern 4a as a mask, the metal-containing film 3 is dry-etched using a chlorine-based gas to form a metal-containing film pattern 3a. Further, as shown in FIG. 1(F), after removing the silicon-containing resist intermediate film pattern 4a, using the metal-containing film pattern 3a as a mask, the processed layer 2 is etched to form a pattern 2a.

[0211] When forming an inorganic hard mask, the silicon-containing resist intermediate film 4 may be changed to an inorganic hard mask. When forming a BARC, a BARC may be formed between the silicon-containing resist intermediate film 4 and the resist upper layer film 5. The etching of the BARC may be continuously performed prior to the etching of the silicon-containing resist intermediate film 4, or the etching of only the BARC may be performed and then the etching of the silicon-containing resist intermediate film 4 may be performed after changing the etching apparatus or the like.

[0212] Further, the present invention provides a method for forming a pattern on a substrate to be processed, comprising: (III-1) a step of forming a metal-containing film by applying the composition for forming a metal-containing film of the present invention on a substrate to be processed and then performing a heat treatment; (III-2) a step of forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film on the metal-containing film; (III-3) a step of forming an organic thin film on the inorganic hard mask intermediate film; (III-4) a step of forming a resist upper layer film using a photoresist material on the organic thin film; (III-5) a step of performing pattern exposure on the resist upper layer film and then developing with a developer to form a pattern on the resist upper layer film; (III-6) a step of transferring the pattern to the organic thin film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film on which the pattern is formed as a mask; (III-7) a step of transferring the pattern to the metal-containing film by dry etching using the inorganic hard mask intermediate film on which the pattern is transferred as a mask; and (III-8) a step of processing the substrate to be processed using the metal-containing film on which the pattern is formed as a mask to form a pattern on the substrate to be processed. A pattern forming method having the above steps is provided.

[0213] Furthermore, in the present invention, as a pattern forming method by a four-layer resist process using the composition for forming a metal-containing film as described above, (IV-1) A step of forming a metal-containing film by applying the composition for forming a metal-containing film of the present invention on a substrate to be processed and then performing heat treatment. (IV-2) A step of forming an organic intermediate film on the metal-containing film. (IV-3) A step of forming a combination of a silicon-containing resist intermediate film or an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film and an organic thin film on the organic intermediate film. (IV-4) A step of forming an upper resist film using a photoresist material on the silicon-containing resist intermediate film or the organic thin film. (IV-5) A step of forming a pattern on the upper resist film by pattern exposure and then developing with a developer. (IV-6) A step of transferring the 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 upper resist film with the pattern as a mask. (IV-7) A step of transferring the pattern to the organic intermediate film by dry etching using the silicon-containing resist intermediate film or the inorganic hard mask intermediate film with the pattern transferred as a mask. (IV-8) A step of transferring the pattern to the metal-containing film by dry etching using the organic intermediate film as a mask, and (IV-9) A step of processing the substrate to be processed using the metal-containing film with the pattern formed as a mask to form a pattern on the substrate to be processed. provided is a patterning method having the above steps.

[0214] As an example of a pattern formation method by a four-layer resist process using such a composition for forming a metal-containing film, a metal-containing film is formed on a substrate to be processed using the composition for forming a metal-containing film, an organic intermediate film is formed on the metal-containing film using an organic resist intermediate film material, a silicon-containing resist intermediate film is formed on the organic intermediate film using a silicon-containing resist intermediate film material, and if necessary, an organic anti-reflective coating (BARC) or an adhesion film is formed on the silicon-containing resist intermediate film. A resist upper layer film is formed on the silicon-containing film or the BARC using a photoresist material. After the resist upper layer film is pattern-exposed, it is developed with a developer to form a pattern in the resist upper layer film. Using the resist upper layer film having the pattern formed thereon as a mask, the pattern is transferred to the BARC or the adhesion film and the silicon-containing resist intermediate film by dry etching. Using the silicon-containing resist intermediate film having the pattern transferred thereto as a mask, the pattern is transferred to the organic intermediate film by dry etching. Using the organic intermediate film as a mask, the pattern is transferred to the metal-containing film. Using the metal-containing film having the pattern formed thereon as a mask, the substrate to be processed is processed to form a pattern on the substrate to be processed. Provided is a pattern formation method characterized by having such a process.

[0215] Examples of the organic resist intermediate film material that can be used for the organic intermediate film include those already known as the lower layer film for the three-layer resist method or the two-layer resist method using a silicon resist composition, 4,4'-(9-fluorenylidene) bisphenol novolak resin (molecular weight 11,000) described in JP-A-2005-128509, and a number of resins including novolak resins, which are known as resist lower layer film materials for the two-layer resist method and the three-layer resist method, etc. can be used. Also, when it is desired to increase the heat resistance compared to ordinary novolak, a polycyclic skeleton such as 6,6'-(9-fluorenylidene)-di(2-naphthol) novolak resin can be incorporated, and a polyimide-based resin can also be selected (for example, JP-A-2004-153125).

[0216] The above organic intermediate film can be formed on a substrate to be processed by a spin coating method or the like using a composition solution, similar to a photoresist composition. After forming the organic intermediate film by a spin coating method or the like, it is desirable to perform baking 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.

[0217] Instead of the above organic resist intermediate film material, an organic hard mask formed by a CVD method or an ALD method can also be applied.

[0218] Since the organic intermediate film of the above multilayer resist process exhibits etching resistance to chlorine-based gases, in the above multilayer resist process, it is preferable to perform dry etching of the metal-containing film using the organic intermediate film as a mask with an etching gas mainly composed of chlorine-based gas.

[0219] Also, in the present invention, a method for forming a tone-inverted pattern on a substrate to be processed, (V-1) A step of forming a resist lower layer film on the substrate to be processed, (V-2) A step of forming a combination of a resist intermediate film or an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film and an organic thin film on the resist lower layer film, (V-3) A step of forming a resist upper layer film using a photoresist material on the resist intermediate film or the combination of the inorganic hard mask intermediate film and the organic thin film, (V-4) After pattern exposure of the resist upper layer film, developing with a developer to form a pattern on the resist upper layer film, (V-5) A step of transferring the pattern to the resist intermediate film or the organic thin film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film having the pattern as a mask, (V-6) A step of transferring the pattern to the resist lower layer film by dry etching using the resist intermediate film or the inorganic hard mask intermediate film having the pattern transferred as a mask, (V-7) A step of coating the resist underlayer film on which the pattern is formed with the composition for forming a metal-containing film of the present invention, followed by heat treatment to coat the metal-containing film and filling the space between the resist underlayer film patterns with the metal-containing film. (V-8) A step of etching back the metal-containing film covering the resist underlayer film on which the pattern is formed by chemical stripper or dry etching to expose the upper surface of the resist underlayer film on which the pattern is formed. (V-9) A step of removing the resist intermediate film or the hard mask intermediate film remaining on the upper surface of the resist underlayer film by dry etching. (V-10) A step of removing the resist underlayer film on which the pattern is formed with the surface exposed by dry etching to form an inverted pattern of the original pattern made of a metal-containing film. (V-11) A step of processing the substrate to be processed using the metal-containing film on which the inverted pattern is formed as a mask to form an inverted pattern on the substrate to be processed. provided is a patterning method having the above steps.

[0220] An example of the tone inversion type pattern forming method of the present invention will be described with reference to FIG. 2. For steps (V-1) to (V-6), it can be carried out in the same manner as FIGS. 1(A) to (E) except that the metal-containing film 3 is changed to a resist underlayer film 7 made of a coating type organic underlayer film material to form a resist underlayer film pattern 7a (FIGS. 2(G) to (K)). In step (V-7), after applying the composition for forming a metal-containing film of the present invention on the resist underlayer film 7 on which the pattern is formed, heat treatment is performed to coat the metal-containing film 8 and fill the spaces between the resist underlayer film patterns 7a with the metal-containing film 8 (FIG. 2(L)). In step (V-8), the metal-containing film 8 covering the resist underlayer film 7 on which the pattern is formed is etched back by a chemical stripper or dry etching to expose the upper surface of the resist underlayer film 7 on which the pattern is formed (FIG. 2(M)). In step (V-9), the resist intermediate film remaining on the upper surface of the resist underlayer film 7 or the hard mask intermediate film is removed by dry etching (FIG. 2(N)). In step (V-10), the resist underlayer film 7 on which the pattern with the exposed surface is formed is removed by dry etching to form a metal-containing film pattern 8a in which the resist underlayer film pattern made of the metal-containing film 8 is inverted (FIG. 2(O)). In step (V-11), the substrate to be processed 2 is processed using the metal-containing film 8 in which the inverted pattern is formed as a mask to form a pattern 2a (inverted pattern) on the substrate to be processed.

[0221] In the pattern forming method of the present invention, in step (I-3), step (II-4), step (III-5), step (IV-5), and step (V-4), it is preferable to perform the pattern exposure using EUV light.

Example

[0222] Hereinafter, the present invention will be described more specifically by showing synthesis examples, examples, and comparative examples, but the present invention is not limited thereto.

[0223] [Compounds (M-1) to (M-17) for forming a metal-containing film] The following metal compounds (metal salts) were used as the compounds for forming a metal-containing film. (M-1): Titanium(IV) 2-ethylhexanoate (M-2): Chromium(III) tris(2,2,6,6-tetramethyl-3,5-heptanedionato) (M-3): Manganese(III) tris(2,2,6,6-tetramethyl-3,5-heptanedionato) (M-4): Iron(III) tris(2,2,6,6-tetramethyl-3,5-heptanedionato) (M-5): Cobalt(II) 2-ethylhexanoate (M-6): Nickel(II) bis(hexafluoroacetylacetonato) (M-7): Copper(I) 2-ethylhexanoate (M-8): Zinc(II) 4-vinylbenzoate (M-9): Zirconium(IV) tetra(2,2,6,6-tetramethyl-3,5-heptanedionato) (M-10): Molybdenum(IV) 2-ethylhexanoate (M-11): Indium(III) ethylbutyrate (M-12): Tin(II) acetate (M-13): Tin(II) 2-ethylhexanoate (M-14): Tin(II) acetylacetonate (M-15): Tin(II) 4-fluorobenzoate (M-16): Hafnium(IV) carboxyethyl acrylate (M-17): Bismuth(III) 2-ethylhexanoate

[0224] [Crosslinking agents (XL-1) to (XL-2)] The crosslinking agents (XL-1) to (XL-2) used in the composition for forming a metal-containing film are shown below. [Chem.]

[0225] [Acid generator (D-1)] The acid generator (D-1) used in the composition for forming a metal-containing film is shown below. [Chem.]

[0226] [Flowability Promoters (BPA-1) to (BPA-7)] (Synthesis of Flowability Promoter) For the synthesis of the flowability promoter (resin), the following organic group raw material groups g: (G1) to (G7) and modifiers H: (H1) to (H5) were used.

[0227] The organic group raw material groups g: (G1) to (G7) are shown below. [Chemical Formula]

[0228] The modifier groups H: (H1) to (H5) are shown below. [Chemical Formula]

[0229] [Synthesis Example 1] Synthesis of Flowability Promoter (BPA-1) Under a nitrogen atmosphere, 200 g of N-methylpyrrolidone was added to 20.0 g of the compound (G1) of the raw material group, 16.4 g of the modifier (H1), and 23.3 g of potassium carbonate, and the reaction was carried out at an internal temperature of 140 °C for 24 hours. After cooling to room temperature, 300 ml of methyl isobutyl ketone and 300 ml of pure water were added to the reaction solution to make it homogeneous, and then the separated aqueous layer was removed. Further, the organic layer was washed twice with 100 ml of 3% nitric acid aqueous solution and five times with 100 ml of pure water, and then the organic layer was dried under reduced pressure to dryness. 100 g of THF was added to the residue to make a homogeneous solution, and then crystallized with 350 g of methanol. The precipitated crystals were separated by filtration, washed twice with 200 g of methanol, and recovered. The recovered crystals were vacuum dried at 70 °C to obtain the compound (BPA-1) for the flowability promoter. When the weight average molecular weight (Mw) and dispersity (Mw / Mn) were determined by GPC, the following results were obtained. (BPA-1): Mw = 580, Mw / Mn = 1.03 [Chemical Formula]

[0230] [Synthesis Example 2] Synthesis of Fluidity Promoter (BPA-2) Under a nitrogen atmosphere, 45.5 g of compound (G2) of the raw material group, 9.8 g of potassium carbonate, and 150 g of DMF were added and made into a homogeneous dispersion at an internal temperature of 50°C. 17.6 g of modifier (H2) was slowly added, and the reaction was carried out at an internal temperature of 50°C for 24 hours. 300 ml of methyl isobutyl ketone and 300 g of pure water were added to the reaction solution to dissolve the precipitated salt, and then the separated aqueous layer was removed. Further, the organic layer was washed 6 times with 100 g of 3% nitric acid aqueous solution and 100 g of pure water, and then the organic layer was dried under reduced pressure to obtain a compound for fluidity promoter (BPA-2). When the weight average molecular weight (Mw) and dispersity (Mw / Mn) were determined by GPC, the following results were obtained. (BPA-2): Mw = 965, Mw / Mn = 1.08 [Chemical formula]

[0231] [Synthesis Example 3] Synthesis of Fluidity Promoter (BPA-3) Under a nitrogen atmosphere, 47.2 g of compound (G3), 11.7 g of potassium carbonate, and 150 g of DMF were added and made into a homogeneous dispersion at an internal temperature of 50°C. 17.2 g of modifier (H3) was slowly added, and the reaction was carried out at an internal temperature of 50°C for 24 hours. 300 ml of methyl isobutyl ketone and 300 g of pure water were added to the reaction solution to dissolve the precipitated salt, and then the separated aqueous layer was removed. Further, the organic layer was washed 6 times with 100 g of 3% nitric acid aqueous solution and 100 g of pure water, and then the organic layer was dried under reduced pressure to obtain a polymer for fluidity promoter (BPA-3). When the weight average molecular weight (Mw) and dispersity (Mw / Mn) were determined by GPC, the following results were obtained. (BPA-3): Mw = 740, Mw / Mn = 1.03 [Chemical formula]

[0232] [Synthesis Example 4] Synthesis of Fluidity Promoter (BPA-4) Under a nitrogen atmosphere, 100 g of N-methylpyrrolidone was added to 30.00 g of compound (G4) in the raw material group. After forming a homogeneous solution at an internal temperature of 40°C under a nitrogen atmosphere, 13.7 g of modifier (H4) was added, and the reaction was carried out at an internal temperature of 40°C for 3 hours to obtain an amic acid solution. 200 g of o-xylene was added to the obtained amic acid solution, and the reaction was carried out for 9 hours while removing the low-boiling substances generated and the water generated from the system at an internal temperature of 150°C to perform dehydration imidization. After completion of the reaction, it was cooled to room temperature and crystallized in 1000 g of methanol. The precipitated crystals were separated by filtration, washed twice with 500 g of methanol, and recovered. The recovered crystals were vacuum dried at 70°C to obtain the compound (BPA-4) for the fluidity promoter. When the weight average molecular weight (Mw) and dispersity (Mw / Mn) were determined by GPC, the following results were obtained. (BPA-4): Mw = 930, Mw / Mn = 1.01 [Chemical formula]

[0233] [Synthesis Example 5] Synthesis of Fluidity Promoter (BPA-5) Under a nitrogen atmosphere, 44.7 g of compound (G5), 16.5 g of potassium carbonate, and 150 g of DMF were added to form a homogeneous dispersion at an internal temperature of 50°C. 23.5 g of modifier (H2) was slowly added, and the reaction was carried out at an internal temperature of 50°C for 24 hours. 300 ml of methyl isobutyl ketone and 300 g of pure water were added to the reaction solution to dissolve the precipitated salt, and then the separated aqueous layer was removed. Further, the organic layer was washed 6 times with 100 g of 3% nitric acid aqueous solution and 100 g of pure water, and then the organic layer was dried to dryness under reduced pressure to obtain the polymer (BPA-5) for the fluidity promoter. When the weight average molecular weight (Mw) and dispersity (Mw / Mn) were determined by GPC, the following results were obtained. (BPA-5): Mw = 2700, Mw / Mn = 3.20 [Chemical formula]

[0234] [Synthesis Example 6] Synthesis of Fluidity Promoter (BPA-6) Under a nitrogen atmosphere, 20.0 g of compound (G6) in the raw material group, 34.5 g of potassium carbonate, and 100 g of DMF were added and made into a homogeneous dispersion at an internal temperature of 50°C. 23.8 g of modifier (H2) was slowly added and the reaction was carried out at an internal temperature of 50°C for 24 hours. 300 ml of methyl isobutyl ketone and 300 g of pure water were added to the reaction solution to dissolve the precipitated salt, and then the separated aqueous layer was removed. Further, the organic layer was washed 6 times with 100 g of 3% aqueous nitric acid solution and 100 g of pure water, and then the organic layer was dried under reduced pressure to obtain resin (BPA-6). When the weight average molecular weight (Mw) and dispersity (Mw / Mn) were determined by GPC, the following results were obtained. (BPA-6): Mw = 9,400, Mw / Mn = 3.59 [Chemical formula]

[0235] [Synthesis Example 7] Synthesis of Fluidity Promoter (BPA-7) 80.0 g of epoxy compound (G7), 51.0 g of modifier (H5), and 600 g of 2-methoxy-1-propanol were made into a homogeneous solution at an internal temperature of 100°C under a nitrogen atmosphere. Then, 5.7 g of benzyltriethylammonium chloride was added and stirred at an internal temperature of 120°C for 12 hours. After cooling to room temperature, 1,500 g of methyl isobutyl ketone was added, and the organic layer was washed 5 times with 300 g of pure water. The organic layer was dried under reduced pressure to obtain compound (BPA-7) for fluidity promoter. When the weight average molecular weight (Mw) and dispersity (Mw / Mn) were determined by GPC, the following results were obtained. (BPA-7): Mw = 900, Mw / Mn = 1.04 [Chemical formula]

[0236] The structures of the compounds and polymers used in the obtained fluidity promoter, as well as the weight average molecular weight (Mw) and dispersity (Mw / Mn), are shown in Tables 1 to 2. For the comparative polymer (R-1), (G5) of the raw material group G used as a raw material in the synthesis example was used.

[0237] [Table 1]

[0238] [Table 2]

[0239] [Synthesis of the Compound (RM-1) for Forming a Metal-Containing Film for Comparative Example] 8.0 g of butyltin trichloride was stirred at room temperature, and 10 g of acrylic acid was added dropwise. After the addition, the temperature was raised to 80 °C and stirred for 7 hours. After completion of the reaction, acrylic acid was removed under reduced pressure to obtain (RM-1). [Chemical Formula]

[0240] [Composition UDL-1 for Forming a Metal-Containing Film] Resin BPA-1 and metal salt (M-13) were dissolved in a mixed solvent of propylene glycol monomethyl ether acetate (PGMEA) containing 0.5% by mass of surfactant FC-4430 (manufactured by Sumitomo 3M Limited) at the ratios shown in Table 3, and filtered through a 0.02 μm membrane filter to prepare a composition (UDL-1) for forming a metal-containing film.

[0241] [Preparation of Compositions (UDL-2 to 27) for Forming a Metal-Containing Film and Comparative Compositions (Comparative Example UDL-1 to 5) for Forming a Metal-Containing Film] Except that the types and contents of the respective components were as shown in Table 3, the operation was the same as that of UDL-1, and each chemical solution was prepared. In Table 3, "-" indicates that the corresponding component was not used. For the high-boiling solvent (F-1), ethylene glycol dibenzyl ether with a boiling point of 364 °C was used. For the metal nanoparticles (NP-1), ZrO2 nanoparticles (5 nm core, 915505, Sigma-Aldrich Corp) were used.

[0242]

Table 3

[0243] Among the above-prepared compositions for forming a metal-containing film, in Comparative Example UDL-5 using a resin containing a phenolic hydroxyl group, generation of precipitates was observed, so the subsequent evaluation was terminated. On the other hand, no generation of precipitates was observed in the compositions UDL-1 to 27 for forming a metal-containing film of the present invention. It is presumed that this is because the resin used as the fluidity promoter does not contain a phenolic hydroxyl group.

[0244] [Examples 1-1 to 1-27, Comparative Examples 1-1 to 1-4: Etching Resistance] The compositions for forming a metal-containing film (UDL-1 to 27 and Comparative Examples UDL-1 to 4) were applied onto a silicon substrate, heated at 350 °C for 60 seconds using a hot plate to form a metal-containing film with a film thickness of 80 nm, and the film thickness A was measured. Next, etching with CF4 gas was performed for 30 seconds under the following conditions using a dry etching apparatus TE-8500 manufactured by Tokyo Electron Limited, and the film thickness B was measured. The film thickness etched in 30 seconds (film thickness B - film thickness A) was calculated as the etching resistance.

[0245] In the etching using CF4 gas, when the film thickness difference between B and A was less than 30 nm, it was rated as "A" (extremely good), when it was 30 nm or more and less than 50 nm, it was rated as "B" (good), and when it was 50 nm or more, it was rated as "C" (poor). The results are shown in Table 4.

[0246] Dry etching conditions with CF4 gas Chamber pressure: 100 mT RF Power (upper part): 500 W RF Power (lower part): 400 W CF4 gas flow rate: 300 sccm Time: 30 sec

[0247]

Table 4

[0248] As shown in Table 4, it was found that Examples 1-1 to 1-27 using the composition for forming a metal-containing film of the present invention exhibited good etching resistance to CF4 gas. In particular, the composition for forming a metal-containing film using a fluidity promoter (BPA-1 to 5) containing a cald structure showed excellent dry etching resistance.

[0249] On the other hand, Comparative Example UDL-1 without a (B) metal source had insufficient dry etching resistance. Further, Comparative Example UDL-4 using an organotin compound (RM-1) that is not a complex with a carboxylate or β-diketones as the metal source showed an improvement in dry etching resistance compared to Comparative Example UDL-1 with only a fluidity promoter. However, it is presumed that due to the insufficient heat resistance and curability of the organotin compound (RM-1), the proportion of metal oxides contained in the resist underlayer film was small, and the dry etching resistance was not sufficiently improved.

[0250] [Examples 2-1 to 2-27, Comparative Examples 2-1 to 2-4: Embedding property and planarization property evaluation] Each of the above compositions for forming a metal-containing film (UDL-1 to 27, Comparative Examples UDL-1 to 4) was applied onto a SiO2 wafer substrate having a dense line & space pattern (line width 60 nm, line depth 100 nm, distance between the centers of two adjacent lines 120 nm), and heated at the temperature shown in Table 5 for 60 seconds using a hot plate to form a metal-containing film with a film thickness of 80 nm. The substrate used was a base substrate 9 (SiO2 wafer substrate) having a dense line & space pattern as shown in FIGS. 3(Q) (plan view) and (R) (cross-sectional view).

[0251] The cross-sectional shape of each obtained wafer substrate was observed using an electron microscope (S-4700) manufactured by Hitachi, Ltd., and the possibility of embedding in the stepped substrate was confirmed. The results are shown in Table 5.

[0252] When a composition for forming a metal-containing film with poor embedding characteristics is used, in this evaluation, the stepped substrate cannot be successfully embedded. When a composition for forming a metal-containing film with good embedding characteristics is used, in this evaluation, as shown in Fig. 3(S), the metal-containing resist underlayer film 10 can fill the spaces between the lines of the underlying substrate 9 having a dense line & space pattern without gaps. "Good" means embeddable without large voids, and "bad" means non-embeddable.

[0253] Also, as shown in Fig. 4, the cross-sectional shape of each wafer substrate 11 obtained in the above embedding evaluation was observed using a scanning electron microscope (SEM), and the step (Delta 12 in Fig. 4(U)) of the filling film (metal-containing resist underlayer film 12) in the line pattern dense portion and the non-line pattern forming portion was observed using an electron microscope (S-4700) manufactured by Hitachi, Ltd. The results are shown in Table 5. In this evaluation, it can be said that the smaller the step, the better the planarization characteristics.

[0254]

Table 5

[0255] As shown in Table 5, Examples 2-1 to 2-27 using the composition for forming a metal-containing film of the present invention were able to fill the dense line & space pattern without generating voids when baked at 350 °C, and it was confirmed that they had good embedding characteristics. Focusing on the fluidity promoter contained in the composition for forming a metal-containing film, the examples using resins (BPA-2, 4 to 7) having a propargyl group showed excellent planarization characteristics. In particular, the examples using BPA-6 and 7 with a compact resin structure showed excellent planarization characteristics. Furthermore, better flatness results were obtained in Example 2-8 using a high-boiling solvent (F-1).

[0256] On the other hand, in Comparative Example 2-2 using Comparative Example UDL-2 that does not contain a fluidity promoter (resin), voids were observed at the bottom of the pattern. It is presumed that the voids were generated due to the volume shrinkage during the baking of the metal compound.

[0257] Also, in Comparative Example 2-4 using Comparative Example UDL-4 containing a comparative example compound (RM-1) which is a monomolecular tin compound, voids were observed at the bottom of the pattern. It is presumed that this is because the heat resistance and curability of the compound (RM-1) are insufficient.

[0258] [Examples 3-1 to 3-10, Comparative Examples 3-1 to 3-4: Pattern Formation Method] On a Si substrate on which a 100 nm SiO2 film was formed, the above composition for forming a metal-containing film (UDL-1 to 10, and Comparative Example UDL-1 to 4) was used, applied by spin coating, and baked at 350 °C for 60 seconds to prepare a resist underlayer film with a thickness of 80 nm. On top of that, a silicon atom-containing resist intermediate layer material (SOG-1) was applied and baked at 220 °C for 60 seconds to form a resist intermediate layer film with a thickness of 30 nm. On top of that, a single-layer resist for ArF of a resist upper layer film material was applied and baked at 105 °C for 60 seconds to form a photoresist film with a thickness of 100 nm. A liquid 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.

[0259] As the silicon atom-containing resist intermediate layer material (SOG-1), a polymer represented by an ArF silicon-containing intermediate film polymer (SiP1) and a crosslinking catalyst (CAT1) were dissolved in an organic solvent containing 0.1 mass% of FC-4430 (manufactured by Sumitomo 3M Limited) at the ratios shown in Table 6, and filtered through a fluororesin filter with a pore size of 0.1 μm to prepare the silicon atom-containing resist intermediate layer material (SOG-1).

[0260]

Table 6

[0261] As the resist upper layer film material (single-layer resist for ArF), a polymer (RP1), an acid generator (PAG1), and a basic compound (Amine1) were dissolved in a solvent containing 0.1% by mass of surfactant FC-4430 (manufactured by Sumitomo 3M Limited) at the ratios shown in Table 7, and filtered through a 0.1-μm fluororesin filter.

[0262]

Table 7

[0263] The polymer (RP1), acid generator (PAG1), and basic compound (Amine1) used in the resist upper layer film material (single-layer resist for ArF) are shown below.

Chemical formula

[0264] As the immersion protective film material (TC-1), a protective film polymer (PP1) was dissolved in an organic solvent at the ratios shown in Table 8, and filtered through a 0.1-μm fluororesin filter.

[0265]

Table 8

[0266] The protective film polymer (PP1) used in the immersion protective film material (TC-1) is shown below.

Chemical formula

[0267] Next, it was exposed using an ArF immersion exposure apparatus (manufactured by Nikon Corporation; NSR-S610C, NA 1.30, σ 0.98 / 0.78, 35-degree dipole s-polarized illumination, 6% halftone phase shift mask), baked at 100°C for 60 seconds (PEB), developed with a 2.38 mass% aqueous solution of tetramethylammonium hydroxide (TMAH) for 30 seconds, and a 50 nm 1:1 positive line-and-space pattern (resist upper layer film pattern) was obtained.

[0268] Next, using a dry etching apparatus CE-300I manufactured by ULVAC, the silicon-containing resist intermediate film was etched using the resist upper layer film pattern as a mask to form a resist intermediate film pattern, the resist lower layer film was etched using the obtained resist intermediate film pattern as a mask to form a pattern, and the SiO2 film was etched using the obtained resist lower layer film pattern as a mask. The etching conditions are as shown below.

[0269] The pattern cross-section was observed with an S-4700 electron microscope (manufactured by Hitachi, Ltd.). Also, the line dimensions after processing were measured using a length measurement SEM (S9200) manufactured by Hitachi High-Technologies Corporation, and the LWR was observed. The results are shown in Table 9.

[0270] Transfer conditions of the resist upper layer film pattern to the silicon-containing resist intermediate film. Dry etching conditions with CF4 gas Pressure: 1 Pa Antenna RF power: 100 W Bias RF power: 15 W CF4 gas flow rate: 15 sccm Time: 20 sec

[0271] Transfer conditions of the silicon-containing resist intermediate film to the resist lower layer film. Dry etching conditions with Cl2 gas Pressure: 1 Pa Antenna RF power: 320 W Bias RF power: 30 W Cl2 gas flow rate: 25 sccm Time: 60 sec

[0272] Transfer conditions of the resist lower layer film pattern to the SiO2 film. Dry etching conditions with CF4 gas Pressure: 1 Pa Antenna RF power: 100 W Bias RF power: 15 W CF4 gas flow rate: 15 sccm Time: 60 sec

[0273]

Table 9

[0274] As shown in Table 9, in all of the compositions for forming a metal-containing film (UDL-1 to 10) of the present invention, the resist upper layer film pattern was finally successfully transferred onto the substrate, and it was confirmed that they are suitably used for fine processing by the multilayer resist method. In particular, in the examples using the composition for forming a metal-containing film containing a fluidity promoter (BPA-1 to 5) having a cald structure, which showed excellent dry etching resistance in the above evaluation, excellent LWR was shown.

[0275] On the other hand, in Comparative Example 3-1 using Comparative Example UDL-1 which does not contain a (B) metal source, the cross-section of the pattern after substrate processing was not a vertical shape, and deterioration of LWR was observed in the pattern observed from above. In Comparative Example 3-3 using Comparative Example UDL-3 containing metal nanoparticles, the cross-sectional shape of the pattern after substrate processing was a vertical shape, but deterioration of LWR was observed in the pattern observed from above. In Comparative Example 3-4 using Comparative Example UDL-4 containing a comparative example compound (RM-1) which is an organic tin compound, the cross-section of the pattern after substrate processing was not a vertical shape, and deterioration of LWR was observed in the pattern observed from above. It is presumed that this is because the heat resistance and curability of the organic tin compound (RM-1) were insufficient, the proportion of metal oxide contained in the resist lower layer film was small, and the dry etching resistance was not sufficiently improved.

[0276] From the above, the composition for forming a metal-containing film of the present invention can form a resist underlayer film with a high metal content rate, and thus exhibits excellent dry etching resistance compared to conventional organic resist underlayer films. Furthermore, it is possible to provide a resist underlayer film material having advanced embedding / planarization characteristics, which was difficult with conventional metal-containing resist underlayer films, and it is extremely useful as a resist underlayer film material used in the multilayer resist method.

[0277] This specification includes the following inventions.

[0278] [1]: A composition for forming a metal-containing film, which contains (A) a resin, (B) a metal source, and (C) an organic solvent, wherein the (A) resin is a resin that does not contain a phenolic hydroxyl group, and the (B) metal source is a salt of a metal selected from Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi and a monovalent to tetravalent carboxylic acid having 1 to 30 carbon atoms, or a complex of the metal and β-diketones. The composition for forming a metal-containing film is characterized by this.

[0279] [2]: The composition for forming a metal-containing film according to the above [1], wherein the (A) resin contains one or more crosslinking groups selected from a substituted or unsubstituted vinyl group, allyl group, allyloxy group, ethynyl group, propargyl group, propargyloxy group, epoxy group, and oxetanyl group.

[0280] [3]: The composition for forming a metal-containing film according to the above [1] or [2], wherein the (A) resin contains an aromatic ring, an alicyclic hydrocarbon, or a heteroaromatic ring and contains a crosslinking group represented by the following formula (1). [Chemical formula] (In the formula, * represents a bonding site to an aromatic ring, an alicyclic hydrocarbon, or a heteroaromatic ring, R A is a divalent organic group having 1 to 10 carbon atoms, R B is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, R C and R Drepresents any one of a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an aryl group having 1 to 10 carbon atoms, and an alkoxy group having 1 to 10 carbon atoms, and L is a divalent organic group having 1 to 10 carbon atoms.)

[0281] [4]: The metal-containing film-forming composition according to any one of [1] to [3] above, wherein the (B) metal source is a salt of the metal and a 1 to 4-valent carboxylic acid having 1 to 30 carbon atoms.)

[0282] [5]: The metal-containing film-forming composition according to any one of [1] to [4] above, wherein the (B) metal source has a structure represented by the following formula (B-1). [Chemical formula] (In the formula, M is selected from any one of Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi, R1 is a monovalent organic group having 1 to 20 carbon atoms, and n is an integer of 1 to 4.)

[0283] [6]: The metal-containing film-forming composition according to any one of [1] to [5] above, wherein the metal of the (B) metal source is Sn.)

[0284] [7]: The metal-containing film-forming composition according to any one of [1] to [6] above, wherein the (A) resin has at least one structural unit represented by the following general formulas (G-1) to (G-5). [Chemical formula] (In the formula, W1 and W2 are each independently a benzene ring or a naphthalene ring, and the hydrogen atoms in the benzene ring and the naphthalene ring may be substituted with a hydrocarbon group having 1 to 6 carbon atoms. R a is the following general formula (Z-1), and Y is a group represented by the following general formula (Z-2). n1 is 0 or 1, n2 is 1 or 2, and V is each independently a hydrogen atom or a linking portion.) [Chemical formula] (In the formula, Z1 has a group represented by the following general formula (Z-3), R a is the following general formula (Z-1), n4 is 0 or 1, n5 is 1 or 2, and V each independently represents a hydrogen atom or a linking moiety.)

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0285] [8]: The metal-containing film-forming composition according to any one of [1] to [7] above, characterized in that the composition further contains one or more of (D) a crosslinking agent, (E) an acid generator, (F) a surfactant, and (G) a pigment.

[0286] [9]: The metal-containing film-forming composition according to any one of [1] to [8] above, characterized in that the (C) organic solvent is a mixture of one or more organic solvents having a boiling point of less than 180°C and one or more organic solvents ((C') high-boiling solvent) having a boiling point of 180°C or higher.

[0287]

[10] : A method for forming a pattern on a substrate to be processed, comprising: (I-1) a step of forming a metal-containing film by applying the composition for forming a metal-containing film according to any one of [1] to [9] above on the substrate to be processed and then performing a heat treatment; (I-2) a step of forming a resist upper layer film on the metal-containing film using a photoresist material; (I-3) a step of forming a pattern on the resist upper layer film by performing pattern exposure on the resist upper layer film and then developing it with a developer; (I-4) a step of transferring the pattern to the metal-containing film by dry etching using the resist upper layer film having the pattern as a mask; and (I-5) a step of processing the substrate to be processed using the metal-containing film having the pattern as a mask to form a pattern on the substrate to be processed A pattern forming method, characterized by having the above.

[0288]

[11] : A method for forming a pattern on a substrate to be processed, comprising: (II-1) a step of forming a metal-containing film by applying the composition for forming a metal-containing film according to any one of [1] to [9] above on the substrate to be processed and then performing a heat treatment; (II-2) a step of forming a silicon-containing resist intermediate film on the metal-containing film; (II-3) a step of forming a resist upper layer film on the silicon-containing resist intermediate film using a photoresist material; (II-4) a step of forming a pattern on the resist upper layer film by performing pattern exposure on the resist upper layer film and then developing it with a developer; (II-5) a step of transferring the pattern to the silicon-containing resist intermediate film by dry etching using the resist upper layer film having the pattern as a mask; (II-6) a step of transferring the pattern to the metal-containing film by dry etching using the silicon-containing resist intermediate film having the pattern transferred thereto as a mask; and (II-7) a step of processing the substrate to be processed using the metal-containing film having the pattern as a mask to form a pattern on the substrate to be processed. A pattern forming method, characterized by having the above steps.

[0289]

[12] : A method for forming a pattern on a substrate to be processed, comprising: (III-1) a step of forming a metal-containing film by applying the composition for forming a metal-containing film according to any one of [1] to [9] above on the substrate to be processed and then performing heat treatment; (III-2) a step of forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film on the metal-containing film; (III-3) a step of forming an organic thin film on the inorganic hard mask intermediate film; (III-4) a step of forming a resist upper layer film using a photoresist material on the organic thin film; (III-5) a step of performing pattern exposure on the resist upper layer film and then developing with a developer to form a pattern on the resist upper layer film; (III-6) a step of transferring the pattern to the organic thin film and the inorganic hard mask intermediate film by dry etching using the resist upper layer film having the pattern formed thereon as a mask; (III-7) a step of transferring the pattern to the metal-containing film by dry etching using the inorganic hard mask intermediate film having the pattern transferred thereon as a mask; and (III-8) a step of processing the substrate to be processed using the metal-containing film having the pattern formed thereon as a mask to form a pattern on the substrate to be processed. A pattern forming method characterized by comprising the above steps.

[0290]

[13] : A method for forming a pattern on a substrate to be processed, comprising: (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 [1] to [9] above on the substrate to be processed and then performing heat treatment; (IV-2) a step of forming an organic intermediate film on the metal-containing film; (IV-3) a step of forming a combination of a silicon-containing resist intermediate film or an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film and an organic thin film on the organic intermediate film; (IV-4) a step of forming a resist upper layer film using a photoresist material on the silicon-containing resist intermediate film or the organic thin film. (IV-5) After pattern-exposing the resist upper layer film, developing it with a developer to form a pattern in the resist upper layer film; (IV-6) Using the resist upper layer film on which the pattern is formed as a mask, transferring the pattern to the silicon-containing resist intermediate film or the organic thin film and the inorganic hard mask intermediate film by dry etching; (IV-7) Using the silicon-containing resist intermediate film or the inorganic hard mask intermediate film on which the pattern is transferred as a mask, transferring the pattern to the organic intermediate film by dry etching; (IV-8) Using the organic intermediate film as a mask, transferring the pattern to the metal-containing film by dry etching; and (IV-9) Processing the substrate to be processed using the metal-containing film on which the pattern is formed as a mask to form a pattern on the substrate to be processed. A pattern forming method characterized by comprising these steps.

[0291]

[14] : A method for forming a tone inversion pattern on a substrate to be processed, comprising: (V-1) forming a resist underlayer film on the substrate to be processed; (V-2) forming a combination of a resist intermediate film or an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film and an organic thin film on the resist underlayer film; (V-3) forming a resist upper layer film using a photoresist material on the resist intermediate film or the combination of the inorganic hard mask intermediate film and the organic thin film; (V-4) after pattern-exposing the resist upper layer film, developing it with a developer to form a pattern in the resist upper layer film; (V-5) using the resist upper layer film having the pattern formed thereon as a mask, transferring the pattern to the resist intermediate film or the organic thin film and the inorganic hard mask intermediate film by dry etching; (V-6) using the resist intermediate film or the inorganic hard mask intermediate film having the pattern transferred thereto as a mask, transferring the pattern to the resist underlayer film by dry etching; (V-7) applying the composition for forming a metal-containing film according to any one of [1] to [9] above on the resist underlayer film having the pattern formed thereon, and then performing heat treatment to coat the metal-containing film and fill the space between the resist underlayer film patterns with the metal-containing film; (V-8) etching back the metal-containing film covering the resist underlayer film having the pattern formed thereon by a chemical stripper or dry etching to expose the upper surface of the resist underlayer film having the pattern formed thereon; (V-9) removing the resist intermediate film or the hard mask intermediate film remaining on the upper surface of the resist underlayer film by dry etching; (V-10) removing the resist underlayer film having the pattern formed thereon with the surface exposed by dry etching to form an inverted pattern of the original pattern made of the metal-containing film; (V-11) processing the substrate to be processed using the metal-containing film having the inverted pattern formed thereon as a mask to form an inverted pattern on the substrate to be processed. A pattern formation method characterized by comprising the above steps.

[0292]

[15] : The pattern formation method according to

[10] above, characterized in that in the step (I-3), the pattern exposure is performed using EUV light.

[0293]

[16] : The pattern formation method according to

[11] above, wherein in the step (II-4), the pattern exposure is performed using EUV light.

[0294]

[17] : The pattern formation method according to

[12] above, wherein in the step (III-5), the pattern exposure is performed using EUV light.

[0295]

[18] : The pattern formation method according to

[13] above, wherein in the step (IV-5), the pattern exposure is performed using EUV light.

[0296]

[19] : The pattern formation method according to

[14] above, wherein in the step (V-4), the pattern exposure is performed using EUV light.

[0297] Note that the present invention is not limited to the above embodiments. The above embodiments are examples, and any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and exhibits the same operational effects is included in the technical scope of the present invention.

Explanation of reference numerals

[0298] 1... Substrate to be processed, 2... Layer to be processed, 2a... Pattern (pattern formed on the 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 lower layer film made of a coating-type organic lower layer film material, 7a... Resist lower layer film pattern, 8... Metal-containing film, 8a... Metal-containing film pattern obtained by inverting the resist lower layer film pattern, 9... Lower substrate having dense lines & spaces, 10... Metal-containing resist lower layer film, 11…Dense line & space having a lower base substrate, 12…Metal-containing resist lower layer film, Delta12…Step difference between the patterned portion and the non-patterned portion of the metal-containing resist lower layer film 12.

Claims

1. A composition for forming a metal-containing film, comprising (A) a resin, (B) a metal source, and (C) an organic solvent, wherein the (A) resin is a resin containing no phenolic hydroxyl group, and the (B) metal source is a salt of a metal selected from Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi and a C1-C30 monovalent to tetravalent carboxylic acid, or a complex of the metal and β-diketones. The composition for forming a metal-containing film is characterized by this.

2. The composition for forming a metal-containing film according to claim 1, wherein the (A) resin contains one or more crosslinking groups selected from a substituted or unsubstituted vinyl group, allyl group, allyloxy group, ethynyl group, propargyl group, propargyloxy group, epoxy group, and oxetanyl group.

3. The composition for forming a metal-containing film according to claim 1, wherein the (A) resin contains an aromatic ring, an alicyclic hydrocarbon, or a heteroaromatic ring and contains a crosslinking group represented by the following formula (1). 【Chemical 1】 (In the formula, * represents a bonding site to an aromatic ring, an alicyclic hydrocarbon, or a heteroaromatic ring, and R Ａ is a divalent organic group having 1 to 10 carbon atoms, R Ｂ is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, R Ｃ and R Ｄ each represents 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, and L is a divalent organic group having 1 to 10 carbon atoms.)

4. The composition for forming a metal-containing film according to claim 1, wherein the (B) metal source is a salt of the metal and a C1-C30 monovalent to tetravalent carboxylic acid.

5. The composition for forming a metal-containing film according to claim 1, wherein the (B) metal source has a structure represented by the following formula (B-1). [Chemical Formula 2] (In the formula, M is selected from any of Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Zr, Mo, In, Sn, Hf, and Bi, and R １ is a monovalent organic group having 1 to 30 carbon atoms, and n is an integer of 1 to 4.)

6. The composition for forming a metal-containing film according to claim 1, wherein the metal of the (B) metal source is Sn.

7. The composition for forming a metal-containing film according to any one of claims 1 to 6, wherein the (A) resin has at least one structural unit represented by the following general formulas (G-1) to (G-5). 【Chemical Formula 3】 (wherein W １ and W ２ are each independently a benzene ring or a naphthalene ring, and the hydrogen atoms in the benzene ring and the naphthalene ring may be substituted with a hydrocarbon group having 1 to 6 carbon atoms. R ａ is the following general formula (Z-1), and Y is a group represented by the following general formula (Z-2). n １ is 0 or 1, n ２ is 1 or 2, and V each independently represents a hydrogen atom or a linking moiety.) [Chemical 4] (In the formula, Z １ has a group represented by the following general formula (Z-3), R ａ is the following general formula (Z-1), n ４ is 0 or 1, n ５ is 1 or 2, and V each independently represents a hydrogen atom or a linking group.) 【Chemical Formula 5】 (In the formula, * represents the bonding site to the oxygen atom, and R Ｂ is a divalent organic group having 1 to 10 carbon atoms, and R Ａ is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms.) 【Chemical Formula 6】 (In the formula, * represents a bond.) 【Chemical Formula 7】 (wherein, * represents a bond, W １ , W ２ , Y, n １ are the same as described above.) 【Chemical 8】 (wherein, m ３ and m ４ represents 1 or 2, and Z is either a single bond or a structure represented by the following general formula (Z-4). R ｘ is either a structure represented by the following general formula (Z-5).) 【Chemical Formula 9】 (wherein, * represents a bond, l represents an integer of 0 to 3, and R ａ ~ R ｆ each independently represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, a phenyl group, or a phenylethyl group which may be substituted with fluorine, and R ａ and R ｂ may combine to form a cyclic compound.) 【Chemical 10】 (In the formula, * represents the bonding site to the aromatic ring, and Q １ is a linear saturated hydrocarbon group having 1 to 30 carbon atoms, or has a structure represented by the following general formula (Z-6).) 【Chemical 11】 (In the formula, * represents the bonding site to the carbonyl group, and R ａ is the general formula (Z-1), and R ｊ represents a linear or branched hydrocarbon group having 1 to 10 carbon atoms, a halogen atom, a nitro group, an amino group, a nitrile group, an alkoxycarbonyl group having 1 to 10 carbon atoms, or an alkanoyloxy group having 1 to 10 carbon atoms. h ３ and h ４ represent the number of substituents on the aromatic ring, each representing an integer from 0 to 7. However, h ３ + h ４ is 0 or more and 7 or less. h ５ represents 0 to 2.) 【Chemical Formula 12】 (In the formula, R １ is a saturated monovalent organic group having 1 to 30 carbon atoms or an unsaturated monovalent organic group having 2 to 30 carbon atoms, X is a divalent organic group having 1 to 30 carbon atoms, and R ａ is the general formula (Z-1), p is an integer from 0 to 5, q １ is an integer from 1 to 6, p + q １ is an integer of 1 or more and 6 or less, and q ２ is 0 or 1.)

8. The composition for forming a metal-containing film according to claim 1, wherein the composition further contains one or more of (D) a crosslinking agent, (E) an acid generator, (F) a surfactant, and (G) a pigment.

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

10. A method for forming a pattern on a substrate to be processed, comprising Step (I-1) of forming a metal-containing film by applying the composition for forming a metal-containing film according to any one of claims 1 to 9 on a substrate to be processed and then performing heat treatment; Step (I-2) of forming a resist upper layer film on the metal-containing film using a photoresist material; Step (I-3) of performing pattern exposure on the resist upper layer film and then developing with a developer to form a pattern in the resist upper layer film; Step (I-4) of transferring the pattern to the metal-containing film by dry etching using the resist upper layer film having the pattern as a mask, and Step (I-5) of processing the substrate to be processed using the metal-containing film having the pattern as a mask to form a pattern on the substrate to be processed A pattern forming method characterized by comprising the above steps.

11. A method of forming a pattern on a substrate to be processed, comprising: Step (II-1) of forming a metal-containing film by applying the composition for forming a metal-containing film according to any one of claims 1 to 9 on a substrate to be processed and then performing heat treatment; Step (II-2) of forming a silicon-containing resist intermediate film on the metal-containing film; Step (II-3) of forming a resist upper layer film on the silicon-containing resist intermediate film using a photoresist material; Step (II-4) of performing pattern exposure on the resist upper layer film and then developing with a developer to form a pattern in the resist upper layer film; Step (II-5) of transferring the pattern to the silicon-containing resist intermediate film by dry etching using the resist upper layer film having the pattern as a mask; Step (II-6) of transferring the pattern to the metal-containing film by dry etching using the silicon-containing resist intermediate film having the pattern transferred thereto as a mask, and Step (II-7) of processing the substrate to be processed using the metal-containing film having the pattern as a mask to form a pattern on the substrate to be processed A pattern forming method characterized by comprising the above steps.

12. A method of forming a pattern on a substrate to be processed, comprising: Step (III-1) of forming a metal-containing film by applying the composition for forming a metal-containing film according to any one of claims 1 to 9 on a substrate to be processed and then performing heat treatment; Step (III-2) of forming an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film on the metal-containing film; Step (III-3) of forming an organic thin film on the inorganic hard mask intermediate film (III-4) A step of forming an upper resist film on the organic thin film using a photoresist material; (III-5) A step of performing pattern exposure on the upper resist film and then developing it with a developer to form a pattern in the upper resist film; (III-6) A step of transferring the pattern to the organic thin film and the inorganic hard mask intermediate film by dry etching using the upper resist film with the pattern formed thereon as a mask; (III-7) A step of transferring the pattern to the metal-containing film by dry etching using the inorganic hard mask intermediate film with the pattern transferred thereon as a mask, and (III-8) A step of processing the substrate to be processed using the metal-containing film with the pattern formed thereon as a mask to form a pattern on the substrate to be processed A pattern forming method characterized by comprising the above steps.

13. A method for forming a pattern on a substrate to be processed, comprising: (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 9 on the substrate to be processed and then performing heat treatment; (IV-2) A step of forming an organic intermediate film on the metal-containing film; (IV-3) A step of forming a combination of a silicon-containing resist intermediate film or an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film and an organic thin film on the organic intermediate film; (IV-4) A step of forming an upper resist film on the silicon-containing resist intermediate film or the organic thin film using a photoresist material; (IV-5) A step of performing pattern exposure on the upper resist film and then developing it with a developer to form a pattern in the upper resist film; (IV-6) A step of transferring the 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 upper resist film with the pattern formed thereon as a mask; (IV-7) A step of transferring the pattern to the organic intermediate film by dry etching using the silicon-containing resist intermediate film or the inorganic hard mask intermediate film with the pattern transferred thereon as a mask; (IV-8) A step of transferring the pattern to the metal-containing film by dry etching using the organic intermediate film as a mask, and (IV-9) A step of processing the substrate to be processed using the metal-containing film with the pattern formed thereon as a mask to form a pattern on the substrate to be processed A pattern forming method characterized by comprising the above steps.

14. A method of forming a tone inversion pattern on a substrate to be processed, comprising: (V-1) forming a resist underlayer film on the substrate to be processed; (V-2) forming, on the resist underlayer film, a combination of a resist intermediate film or an inorganic hard mask intermediate film selected from a silicon oxide film, a silicon nitride film, and a silicon oxynitride film and an organic thin film; (V-3) forming a resist upper layer film using a photoresist material on the resist intermediate film or the combination of the inorganic hard mask intermediate film and the organic thin film; (V-4) after pattern-exposing the resist upper layer film, developing it with a developer to form a pattern in the resist upper layer film; (V-5) using the resist upper layer film having the pattern formed thereon as a mask, transferring the pattern to the resist intermediate film or the organic thin film and the inorganic hard mask intermediate film by dry etching; (V-6) using the resist intermediate film or the inorganic hard mask intermediate film having the pattern transferred thereto as a mask, transferring the pattern to the resist underlayer film by dry etching; (V-7) applying the composition for forming a metal-containing film according to any one of claims 1 to 9 on the resist underlayer film having the pattern formed thereon, and then performing heat treatment to coat the metal-containing film and fill the spaces between the resist underlayer film patterns with the metal-containing film; (V-8) etching back the metal-containing film covering the resist underlayer film having the pattern formed thereon by a chemical stripper or dry etching to expose the upper surface of the resist underlayer film having the pattern formed thereon; (V-9) removing the resist intermediate film or the hard mask intermediate film remaining on the upper surface of the resist underlayer film by dry etching; (V-10) removing the resist underlayer film having the pattern formed thereon with the surface exposed by dry etching to form an inverted pattern of the original pattern made of the metal-containing film; (V-11) processing the substrate to be processed using the metal-containing film having the inverted pattern formed thereon as a mask to form an inverted pattern on the substrate to be processed. A pattern forming method, characterized by comprising the above steps.

15. The pattern forming method according to claim 10, characterized in that, in the step (I-3), the pattern exposure is performed using EUV light.

16. The pattern forming method according to claim 11, wherein in the step (II-4), the pattern exposure is performed using EUV light.

17. The pattern forming method according to claim 12, wherein in the step (III-5), the pattern exposure is performed using EUV light.

18. The pattern forming method according to claim 13, wherein in the step (IV-5), the pattern exposure is performed using EUV light.

19. The pattern forming method according to claim 14, wherein in the step (V-4), the pattern exposure is performed using EUV light.

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