Resist support film composition and pattern forming method using same

Abstract

According to the present invention, provided is a resist auxiliary film composition containing a resin (A) and a solvent (B) containing a compound (B1) represented by general formula (b-1), the content of an active ingredient in the resist auxiliary film composition being 45 mass% or less based on the total amount (in the formula (b-1), R1 represents a hydrogen atom or a hydrogen atom, and R2 represents a hydrogen atom or a hydrogen atom). R0 is an alkyl group having 1-10 carbon atoms, an aryl group having 6-10 carbon atoms, or an acyl group having 1-10 carbon atoms, and R1 is a hydrogen atom or an alkyl group having 1-10 carbon atoms. # imgabs0 #

Description

Technical Field

[0001] The present invention relates to a resist auxiliary film composition and a pattern forming method using the composition. Background Art

[0002] In recent years, with the high integration and high speed of semiconductor devices, finer pattern rules are required. Under such circumstances, various technical developments are being carried out on how to perform fine and high-precision pattern processing with the light source used in the photolithography technology using light exposure, which is currently used as a general technology.

[0003] As the light source for lithography used in the formation of resist patterns, in the parts with low integration, light exposure using the g-line (436nm) or i-line (365nm) of a mercury lamp as the light source is widely used. In the parts with high integration and requiring refinement, lithography technology using KrF excimer laser (248nm) or ArF excimer laser (193nm) with shorter wavelengths has also been put into practical use. In the most cutting-edge technology that requires more refinement, lithography technology using extreme ultraviolet light (EUV, 13.5nm) is also becoming practical. In addition, in order to improve refinement, various resist auxiliary films are used to improve the performance of photoresists.

[0004] With the application of KrF excimer laser and ArF excimer laser, the diffuse reflection of active light from the substrate and the influence of standing waves have become a big problem. As a resist underlayer film for preventing reflection between the photoresist and the processed substrate, the method of setting an anti-reflective film (Bottom Anti-Reflective Coating, bottom anti-reflective coating, BARC) is widely used.

[0005] As antireflection films, inorganic antireflection films such as titanium, titanium dioxide, titanium nitride, chromium oxide, carbon, and α-silicon, and organic antireflection films composed of light-absorbing substances and polymer compounds are known. The former requires equipment such as vacuum evaporation equipment, CVD equipment, and sputtering equipment when forming the film, while the latter has the advantage of not requiring special equipment, and therefore a lot of research has been conducted.

[0006] For example, there can be mentioned an acrylic resin type antireflection film having a hydroxyl group as a crosslinking reaction group and a light absorbing group in the same molecule (see Patent Document 1), a novolac resin type antireflection film having a hydroxyl group as a crosslinking reaction group and a light absorbing group in the same molecule (see Patent Document 2), and the like.

[0007] Preferred physical properties of organic antireflective film materials include high absorbance to light and radiation, no miscibility with the photoresist layer (insoluble in the resist solvent), no diffusion of low molecular weight diffusers from the antireflective film material into the topcoat resist during coating or heat drying, and a dry etching speed faster than that of the photoresist (see non-patent document 1).

[0008] In the device manufacturing process using EUV lithography, due to the adverse effects of the base substrate or EUV, the pattern of the resist for EUV lithography becomes an edge shape or an undercut shape, and a good resist pattern with a straight shape cannot be formed, resulting in low sensitivity to EUV and unsatisfactory production volume. Therefore, although a resist underlayer film (antireflection film) with antireflection capability is not required in EUV lithography, a resist underlayer film for EUV lithography that can reduce their adverse effects, form a good resist pattern with a straight shape, and improve the sensitivity of the resist is required.

[0009] Furthermore, since a resist is coated on the resist underlayer film for EUV lithography after film formation, similarly to an antireflection film, it is essential that the resist underlayer film has no miscibility with the photoresist layer (is insoluble in the resist solvent) and has excellent adhesion to the resist.

[0010] Moreover, in the current generation of products using EUV lithography, since the line width of the resist pattern is very fine, the resist for EUV lithography is expected to be thinner. To this end, it is necessary to significantly reduce the time consumed in the process of removing the organic anti-reflective film by etching, and there is a need for a resist underlayer film for EUV lithography that can be used in a thin film state, or a resist underlayer film for EUV lithography that has a large selectivity ratio with the etching speed of the EUV lithography resist.

[0011] It is also widely known that once the resist pattern tends to be thinned, the ratio of the pattern height to the pattern line width (aspect ratio) will increase in the single-layer resist method used as a typical resist pattern forming method, and the surface tension of the developer during development will cause the pattern to collapse. Therefore, in order to form a pattern with a large aspect ratio on a step substrate, a multilayer resist method in which films with different dry etching properties are stacked to form a pattern is known to be an excellent method. As a result, a double-layer resist method (for example, see Patent Document 3) has been developed in which a photoresist layer formed of a silicon-containing photosensitive polymer is combined with a lower layer formed of an organic polymer having carbon, hydrogen and oxygen as main constituent elements, such as a novolac polymer, and a triple-layer resist method (for example, see Patent Document 4) is combined in which a photoresist layer formed of an organic photosensitive polymer used in the single-layer resist method, an intermediate layer formed of a silicon polymer or a silicon CVD film, and a lower layer formed of an organic polymer are combined.

[0012] In the three-layer resist method, the pattern of the photoresist layer is first transferred to the silicon-containing intermediate layer using a fluorocarbon-based dry etching gas, and then the pattern is used as a mask to dry-etch an organic lower film composed mainly of carbon and hydrogen using an oxygen-containing gas to transfer the pattern, and the organic lower film is used as a mask to form a pattern on the substrate to be processed by dry etching. However, in the semiconductor device manufacturing process of 20nm or later, when the pattern of the organic lower film is used as a hard mask to transfer the pattern to the substrate to be processed by dry etching, the lower film pattern is seen to be distorted or bent.

[0013] The carbon hard mask formed on the processed substrate is usually an amorphous carbon (hereinafter referred to as CVD-C) film made by CVD method using methane gas, ethane gas, acetylene gas, etc. as raw materials. It is known that this CVD-C film can reduce the hydrogen atoms in the film as much as possible, and is very effective for the distortion and bending of the above-mentioned pattern. However, it is also known that when there are steps in the processed substrate of the base, it is difficult to fill such steps due to the characteristics of the CVD process. Therefore, when the processed substrate with steps is buried with a CVD-C film and then a pattern is formed using a photoresist, due to the influence of the steps of the processed substrate, the coating surface of the photoresist also has steps, so the film thickness of the photoresist becomes uneven, resulting in a deterioration of the focus margin and pattern shape during photolithography.

[0014] On the other hand, it is known that when a lower film is formed as a carbon hard mask formed immediately above a substrate to be processed by spin coating, it has the advantage of being able to fill the steps of a stepped substrate. By flattening the substrate with the lower film material, it is possible to suppress the thickness fluctuation of the silicon-containing intermediate layer and the photoresist formed thereon, thereby expanding the focus margin of the photolithography technology and forming a normal pattern.

[0015] Therefore, a lower film material (spin-on carbon film) having high etching resistance when a substrate to be processed is dry-etched and capable of forming a film with high flatness on the substrate to be processed by spin coating, and a method for forming the lower film (spin-on carbon film) are sought.

[0016] Generally, a spin-on carbon film uses a material with a high carbon content. When such a material with a high carbon content is used for a resist underlayer film, the etching tolerance during substrate processing is improved, and as a result, a more accurate pattern transfer can be achieved. As such a spin-on carbon film, a novolac resin is known (for example, see Patent Document 5). In addition, a spin-on carbon film formed by a resist spin-on carbon film composition containing an acenaphthylene polymer is also known to show good performance (for example, see Patent Document 6).

[0017] Prior art literature

[0018] Patent Literature

[0019] Patent Document 1: U.S. Patent No. 5,919,599

[0020] Patent Document 2: U.S. Patent No. 5,693,691

[0021] Patent Document 3: Japanese Patent Application Publication No. 2000-143937

[0022] Patent Document 4: Japanese Patent Application Publication No. 2001-40293

[0023] Patent Document 5: Japanese Patent Application Publication No. 2010-15112

[0024] Patent Document 6: Japanese Patent Application Publication No. 2005-250434

[0025] Non-patent literature

[0026] Non-patent document 1: Proc. SPIE, Vol. 3678, pp. 174-185 (1999) Summary of the invention

[0027] Problems to be solved by the invention

[0028] The photoresist auxiliary film material used in manufacturing various devices such as semiconductor elements and liquid crystal elements has different required performances depending on the type of the device. Therefore, a photoresist auxiliary film material capable of forming a resist auxiliary film suitable for manufacturing various devices is needed.

[0029] Technical solutions to solve problems

[0030] The inventors of the present invention have conducted intensive studies to solve the above problems and have found that the above problems can be solved by a resist auxiliary film composition containing a resin and a solvent containing a compound having a specific structure and limiting the content of the active ingredient to a specified value or less. That is, the present invention is as follows.

[0031] <1> A resist auxiliary film composition comprising a resin (A) and a solvent (B) containing a compound (B1) represented by the following general formula (b-1),

[0032] The resist auxiliary film composition has an active ingredient content of 45% by mass or less based on the total amount.

[0033]

[0034] [In the above formula (b-1), R 0is an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an acyl group having 1 to 10 carbon atoms, R 1 It is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.

[0035] <2> According to the above <1> The resist auxiliary film composition, wherein the solvent (B) does not contain methyl 2-methoxyisobutyrate (MBM), methyl 2-formyloxyisobutyrate (FBM), and methyl 2-acetoxyisobutyrate (ABM).

[0036] <3> According to the above <1> or <2> The resist auxiliary film composition further contains at least one additive (C) selected from a photosensitizer and an acid generator.

[0037] <4> According to the above <1> ~ <3> The resist auxiliary film composition according to any one of the preceding claims, wherein R in the general formula (b-1) 0 is methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, cyclopropyl, cyclopentyl, cyclohexyl, phenyl, naphthyl, formyl, acetyl, propionyl or benzoyl.

[0038] <5> According to the above <1> ~ <4> The resist auxiliary film composition according to any one of the preceding claims, wherein R in the general formula (b-1) 1 It is a hydrogen atom, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a sec-butyl group or a tert-butyl group.

[0039] <6> According to the above <1> ~ <5> The resist auxiliary film composition described in any one of the above, wherein the solvent (B) contains a compound represented by the following general formula (b-2) as a solvent (B2) other than the compound (B1).

[0040]

[0041] [In the above formula (b-2), R 1 It is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.

[0042] <7> According to the above <6> The resist auxiliary film composition, wherein the solvent (B) comprises at least one selected from methyl 2-hydroxyisobutyrate and 2-hydroxyisobutyric acid as the solvent (B2).

[0043] <8> According to the above <6> or <7> The resist auxiliary film composition, wherein the content of the solvent (B2) is less than 100% by mass based on the total amount (100% by mass) of the resist auxiliary film composition.

[0044] <9> According to the above <1> ~ <8> The resist auxiliary film composition described in any one of the above, wherein the resin (A) contains a novolac type resin (A1).

[0045] <10> According to the above <1> ~ <8> The resist auxiliary film composition described in any one of the above, wherein the resin (A) contains an ethylenically unsaturated resin (A2).

[0046] <11> According to the above <1> ~ <8> The resist auxiliary film composition described in any one of the above, wherein the resin (A) contains a high carbon type resin (A3).

[0047] <12> According to the above <1> ~ <8> The resist auxiliary film composition described in any one of the above, wherein the resin (A) comprises a silicon-containing resin (A4).

[0048] <13> According to the above <1> ~ <12> The resist auxiliary film composition described in any one of the above, wherein the resist auxiliary film is a resist underlayer film.

[0049] <14> According to the above <1> ~ <12> The resist auxiliary film composition described in any one of the above, wherein the resist auxiliary film is a resist intermediate layer film.

[0050] <15> According to the above <6> or <7> The resist auxiliary film composition, wherein the content of the solvent (B2) is 100% by mass or less based on the total amount (100% by mass) of the compound (B1).

[0051] <16> A pattern forming method comprising:

[0052] Use the above on the substrate <13> The step (A-1) of forming a resist underlayer film from the resist auxiliary film composition;

[0053] A step (A-2) of forming at least one photoresist layer on the resist underlayer film; and

[0054] After the step (A-2), a step (A-3) of irradiating a predetermined region of the photoresist layer with radiation for development is performed.

[0055] <17> A pattern forming method comprising:

[0056] Use the above on the substrate <13> The step (B-1) of forming a resist underlayer film with the resist auxiliary film composition;

[0057] A step (B-2) of forming a resist intermediate layer film on the resist underlayer film;

[0058] A step (B-3) of forming at least one photoresist layer on the resist intermediate layer film;

[0059] After the step (B-3), a step (B-4) of irradiating a predetermined region of the photoresist layer with radiation and developing the layer to form a resist pattern; and

[0060] After the above-mentioned process (B-4), the above-mentioned resist intermediate layer film is etched using the above-mentioned resist pattern as a mask, the above-mentioned resist lower layer film is etched using the obtained resist intermediate layer film pattern as an etching mask, and the substrate is etched using the obtained resist lower layer film pattern as an etching mask, thereby forming a process (B-5) of forming a pattern on the substrate.

[0061] <18> A pattern forming method comprising:

[0062] A step (B-1) of forming a resist underlayer film on a substrate;

[0063] The above-mentioned resist underlayer film is applied with the above-mentioned <14> A step (B-2) of forming a resist intermediate layer film from the resist auxiliary film composition;

[0064] A step (B-3) of forming at least one photoresist layer on the resist intermediate layer film;

[0065] After the step (B-3), a step (B-4) of irradiating a predetermined region of the photoresist layer with radiation and developing the layer to form a resist pattern; and

[0066] After the above-mentioned process (B-4), the above-mentioned resist intermediate layer film is etched using the above-mentioned resist pattern as a mask, the above-mentioned resist lower layer film is etched using the obtained resist intermediate layer film pattern as an etching mask, and the substrate is etched using the obtained resist lower layer film pattern as an etching mask, thereby forming a process (B-5) of forming a pattern on the substrate.

[0067] Effects of the Invention

[0068] The resist auxiliary film composition according to a preferred embodiment of the present invention can form a resist auxiliary film suitable for manufacturing various devices even though the content of the effective component including the resin is limited to a predetermined value or less. DETAILED DESCRIPTION

[0069] [Resist auxiliary film composition]

[0070] The resist auxiliary film composition of the present invention contains a resin (A) (hereinafter also referred to as "component (A)") and a solvent (B) (hereinafter also referred to as "component (B)") containing a compound (B1) represented by the general formula (b-1). In the present invention, "resist auxiliary film" means all films used as the upper layer of the resist and the lower layer of the resist, for example, including a resist upper layer film, a resist intermediate layer film, and a resist lower layer film.

[0071] In addition, the resist auxiliary film composition according to one embodiment of the present invention preferably further contains at least one additive (C) selected from a photosensitizer and an acid generator (hereinafter also referred to as "component (C)").

[0072] Furthermore, in the resist auxiliary film composition of the present invention, the content of the active ingredient is limited to 45% by mass or less based on the total amount (100% by mass) of the resist auxiliary film composition.

[0073] In this specification, "active ingredients" refers to the ingredients contained in the resist auxiliary film composition except for the ingredient (B). Specifically, the resin (A) and the additive (C), as well as the acid crosslinking agent, acid diffusion control agent, dissolution promoter, dissolution control agent, sensitizer, surfactant, organic carboxylic acid or phosphorus oxygen acid or its derivative, dye, pigment, adhesion promoter, antihalation agent, storage stabilizer, defoaming agent, shape modifier, etc. which may be contained as other additives described later, belong to the active ingredients.

[0074] Generally, in order to be suitable for use as an etching mask, it is necessary to form a thick resist auxiliary film. However, when a resist auxiliary film composition having a small resin content is used, it is difficult to form a thick resist auxiliary film.

[0075] In contrast, in the resist auxiliary film composition of the present invention, by using the compound represented by the general formula (b-1) as a solvent, even if the content of the active ingredient containing the resin is reduced to 45% by mass or less, a photoresist auxiliary film material capable of forming a thick resist auxiliary film can be obtained. In addition, the resist auxiliary film composition of the present invention is economically advantageous because the content of the active ingredient is reduced to 45% by mass or less.

[0076] In addition, in the anti-etching auxiliary film composition of one embodiment of the present invention, the content of the active ingredient can be appropriately set to less than 42 mass%, less than 40 mass%, less than 36 mass%, less than 31 mass%, less than 26 mass%, less than 23 mass%, less than 20 mass%, less than 18 mass%, less than 16 mass%, less than 12 mass%, less than 10 mass%, less than 6 mass% or less than 3 mass% depending on the purpose.

[0077] On the other hand, the lower limit of the content of the active ingredient can also be appropriately set according to the application, and can be set to 1 mass % or more, 2 mass % or more, 4 mass % or more, 7 mass % or more, or 10 mass % or more relative to the total amount (100 mass %) of the anti-etching auxiliary film composition.

[0078] Furthermore, the content of the active ingredient can be appropriately selected from each of the above-mentioned upper limit value and lower limit value, and can be set in any combination.

[0079] In addition, in the anti-etching auxiliary film composition of one embodiment of the present invention, from the perspective of preparing a photoresist auxiliary film material capable of forming a thick anti-etching auxiliary film, the content ratio of component (A) as an active ingredient is preferably 50 to 100 mass %, more preferably 60 to 100 mass %, further preferably 70 to 100 mass %, further preferably 75 to 100 mass %, and particularly preferably 80 to 100 mass % relative to the total amount of active ingredients contained in the anti-etching auxiliary film composition (100 mass %).

[0080] The resist auxiliary film composition according to one embodiment of the present invention may contain other components in addition to the above-mentioned components (A) to (C) depending on the application.

[0081] Among them, in the anti-etching auxiliary film composition of one embodiment of the present invention, the total content of components (A), (B) and (C) is preferably 30 to 100 mass%, more preferably 40 to 100 mass%, further preferably 60 to 100 mass%, further preferably 80 to 100 mass%, and particularly preferably 90 to 100 mass%, based on the total amount (100 mass%) of the anti-etching auxiliary film composition.

[0082] Hereinafter, the details of each component contained in the resist auxiliary film composition according to one embodiment of the present invention will be described.

[0083] <Ingredient (A): Resin>

[0084] The resin (A) contained in the resist auxiliary film composition as one embodiment of the present invention is not particularly limited, and can be a resin for a known antireflection film for KrF excimer laser or ArF excimer laser or a photoresist lower film material for EUV lithography technology, a high carbon concentration resin for a spin-on carbon film used in a double-layer resist method or a triple-layer resist method, a silicon-containing resin for a spin-on glass film used in a double-layer resist method or a triple-layer resist method, and a resin for an upper film of a photoresist for the purpose of antifouling, removing unnecessary wavelengths of light, or waterproofing for immersion exposure, and can be appropriately selected according to the application. In this specification, "resin" refers to a compound having a specified structure in addition to a polymer having a specified structural unit.

[0085] The weight average molecular weight (Mw) of the resin used in one embodiment of the present invention is preferably 500 to 50,000, more preferably 1,000 to 40,000, and even more preferably 1,000 to 30,000.

[0086] In the anti-etching auxiliary film composition of the present invention, the content of component (A) can be appropriately set to 45 mass% or less, 42 mass% or less, 40 mass% or less, 35 mass% or less, 31 mass% or less, 26 mass% or less, 23 mass% or less, 20 mass% or less, 18 mass% or less, 16 mass% or less, 12 mass% or less, 10 mass% or less, 6 mass% or less or 3 mass% or less, based on the total amount (100 mass%) of the anti-etching auxiliary film composition according to the application.

[0087] In addition, the lower limit of the content of component (A) can also be appropriately set according to the application, and can be set to 1 mass % or more, 2 mass % or more, 4 mass % or more, 7 mass % or more, or 10 mass % or more based on the total amount (100 mass %) of the resist auxiliary film composition.

[0088] Furthermore, the content of the component (A) can be appropriately selected from each of the above upper limit and lower limit options and can be set in any combination.

[0089] The resist auxiliary film composition is suitable for use as an antireflection film for KrF excimer laser or ArF excimer laser or a photoresist underlayer film material for EUV lithography technology, a spin-on carbon film used in a double-layer resist method or a triple-layer resist method, and a spin-on glass film used in a triple-layer resist method.

[0090] For example, in the case of making an antireflection film for KrF excimer laser or ArF excimer laser or a photoresist underlayer film material for EUV lithography technology, the resin (A) preferably contains a novolac type resin (A1) or an ethylenically unsaturated type resin (A2).

[0091] In addition, when making a spin-on carbon film used in a double-layer resist method or a triple-layer resist method, it is preferably included in a high-carbon type resin (A3); when making a spin-on glass film used in a triple-layer resist method, it is preferably included in a silicon-containing type resin (A4).

[0092] Furthermore, the resin (A) contained in the resist auxiliary film composition of one embodiment of the present invention may contain only one selected from these resins (A1), (A2), (A3) and (A4), or may contain two or more in combination.

[0093] Furthermore, the resin (A) may contain other resins other than the resins (A1), (A2), (A3) and (A4).

[0094] Among them, the total content ratio of the resins (A1), (A2), (A3) and (A4) in the resin (A) used in one embodiment of the present invention is preferably 60 to 100 mass %, more preferably 70 to 100 mass %, further preferably 80 to 100 mass %, further preferably 90 to 100 mass %, and particularly preferably 95 to 100 mass % relative to the total amount (100 mass %) of the resin (A).

[0095] Hereinafter, these resins (A1), (A2), (A3) and (A4) will be described.

[0096] [Novolac type resin (A1)]

[0097] As the novolac resin (A1) used in one embodiment of the present invention, for example, a resin obtained by reacting phenols with at least one of aldehydes and ketones in the presence of an acidic catalyst (for example, hydrochloric acid, sulfuric acid, oxalic acid, etc.) can be mentioned. The novolac resin (A1) is not particularly limited, and a known resin can be used, for example, the resins listed in Japanese Patent Publication No. 2009-173623, International Patent Publication No. 2013-024779, and International Patent Publication No. 2015-137486 can be used.

[0098] Examples of the phenols include phenol, o-cresol, m-cresol, p-cresol, 2,3-dimethylphenol, 2,5-dimethylphenol, 3,4-dimethylphenol, 3,5-dimethylphenol, 2,4-dimethylphenol, 2,6-dimethylphenol, 2,3,5-trimethylphenol, 2,3,6-trimethylphenol, 2-tert-butylphenol, 3-tert-butylphenol, 4-tert-butylphenol, 2-methylresorcinol, 4-methylresorcinol, catechol, 5-methylresorcinol, 4-tert-butylcatechol, 2-methoxyphenol, 3-methoxyphenol, 2-propylphenol, 3-propylphenol, 4-propylphenol, 2-isopropylphenol, 2-methoxy-5-methylphenol, 2-tert-butyl-5-methylphenol, thymol, isothymol, 4,4'-biphenol, 1-naphthol, 2-naphthol, hydroxyanthracene, hydroxypyrene, 2,6-dihydroxynaphthalene and 2,6-dihydroxynaphthalene, etc.

[0099] These phenols may be used alone or in combination of two or more.

[0100] Examples of the aldehydes include formaldehyde, paraformaldehyde, trioxane, acetaldehyde, propionaldehyde, benzaldehyde, phenylacetaldehyde, α-phenylpropionaldehyde, β-phenylpropionaldehyde, benzaldehyde, 4-biphenylaldehyde, o-hydroxybenzaldehyde, m-hydroxybenzaldehyde, p-hydroxybenzaldehyde, o-chlorobenzaldehyde, m-chlorobenzaldehyde, p-chlorobenzaldehyde, o-methylbenzaldehyde, m-methylbenzaldehyde, p-methylbenzaldehyde, p-ethylbenzaldehyde, 3,4-dimethylbenzaldehyde, p-propylbenzaldehyde, p-n-butylbenzaldehyde, and terephthalaldehyde.

[0101] Examples of ketones include acetone, methyl ethyl ketone, diethyl ketone, acetophenone, and benzophenone.

[0102] These aldehydes and ketones may be used alone or in combination of two or more.

[0103] Among them, as a novolac type resin (A1) used in one embodiment of the present invention, a resin obtained by condensing cresol and aldehydes is preferred, a resin obtained by condensing at least one of m-cresol and p-cresol with at least one of formaldehyde and paraformaldehyde is more preferred, and a resin obtained by using m-cresol and p-cresol at the same time and causing them to condense with at least one of formaldehyde and paraformaldehyde is further preferred.

[0104] When m-cresol and p-cresol are used together, the blending ratio of m-cresol to p-cresol as raw materials [m-cresol / p-cresol] is preferably 10 / 90 to 90 / 10, more preferably 20 / 80 to 80 / 20, and even more preferably 50 / 50 to 70 / 30 in terms of mass ratio.

[0105] As the novolac-type resin (A1) used in one embodiment of the present invention, commercially available products such as "EP4080G" and "EP4050G" (both cresol novolac resins manufactured by Asahi Organic Materials Co., Ltd.) can be used.

[0106] The weight average molecular weight (Mw) of the novolac resin (A1) used in one embodiment of the present invention is preferably 500 to 30,000, more preferably 1,000 to 20,000, further preferably 1,000 to 15,000, and still further preferably 1,000 to 10,000.

[0107] [Ethylenically unsaturated resin (A2)]

[0108] The ethylenically unsaturated resin (A2) used in one embodiment of the present invention is not particularly limited, and a known resin can be used. It can be a resin (A2a) having at least one of a structural unit (a2-1) derived from a compound containing a phenolic hydroxyl group and a structural unit (a2-2) that can be decomposed by the action of an acid, an alkali or heat to form an acidic functional group, or it can be a copolymer having both the structural unit (a2-1) and the structural unit (a2-2).

[0109] Since the resin has at least one of the structural unit (a2-1) and the structural unit (a2-2), the solubility in the compound (B1) can be increased.

[0110] In the resin (A2a) used in one embodiment of the present invention, the total content ratio of the structural unit (a2-1) and the structural unit (a2-2) is preferably 30 mol% or more, more preferably 50 mol% or more, further preferably 60 mol% or more, further preferably 70 mol% or more, and particularly preferably 80 mol% or more, relative to the total amount (100 mol%) of the structural units of the resin (A2a).

[0111] In addition, when the resin (A2a) used in one embodiment of the present invention is a copolymer having both structural units (a2-1) and structural units (a2-2), the content ratio of structural units (a2-1) to structural units (a2-2) [(a2-1) / (a2-2)] is preferably 1 / 10 to 10 / 1, more preferably 1 / 5 to 8 / 1, further preferably 1 / 2 to 6 / 1, and further preferably 1 / 1 to 4 / 1 in terms of molar ratio.

[0112] Examples of the phenolic hydroxyl group-containing compound constituting the structural unit (a2-1) include hydroxystyrenes (o-hydroxystyrene, m-hydroxystyrene, p-hydroxystyrene) and isopropenylphenols (o-isopropenylphenol, m-isopropenylphenol, p-isopropenylphenol), and hydroxystyrene is preferred.

[0113] Examples of the acidic functional group formed by decomposition of the structural unit (a2-2) by the action of an acid, an alkali or heat include a phenolic hydroxyl group and a carboxyl group.

[0114] Monomers capable of forming structural units of phenolic hydroxyl groups include, for example, hydroxy(α-methyl)styrenes protected by acetal groups, such as p-(1-methoxyethoxy)styrene, p-(1-ethoxyethoxy)styrene, p-(1-n-propoxyethoxy)styrene, p-(1-isopropoxyethoxy)styrene, p-(1-cyclohexyloxyethoxy)styrene or α-methyl substitutes thereof; p-acetoxystyrene, tert-butoxycarbonylstyrene, tert-butoxystyrene or α-methyl substitutes thereof; and the like.

[0115] These monomers may be used alone or in combination of two or more.

[0116] In addition, examples of monomers capable of forming a structural unit of a carboxyl group include (meth)acrylates protected by acid-decomposable ester groups such as tert-butyl (meth)acrylate, tetrahydropyranyl (meth)acrylate, 2-methoxybutyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-tert-butoxycarbonyl (meth)acrylate, 2-benzyloxycarbonyl (meth)acrylate, 2-phenoxycarbonyl (meth)acrylate, 2-cyclohexyloxycarbonyl (meth)acrylate, 2-isobornyloxycarbonyl (meth)acrylate, and 2-tricyclodecanyloxycarbonyl (meth)acrylate.

[0117] These monomers may be used alone or in combination of two or more.

[0118] Among them, the monomer constituting the structural unit (a2-2) is preferably at least one selected from tert-butyl (meth)acrylate, tetrahydropyranyl (meth)acrylate, 2-cyclohexyloxycarbonylethyl (meth)acrylate and p-(1-ethoxyethoxy)styrene.

[0119] The resin (A2a) used in one embodiment of the present invention may be a resin having at least one of the structural unit (a2-1) and the structural unit (a2-2) as described above, and may further have other structural units.

[0120] Examples of monomers constituting such other structural units include alkyl (meth)acrylates; hydroxyl-containing monomers; epoxy-containing monomers; alicyclic structure-containing monomers; olefins such as ethylene, propylene, and isobutylene; halogenated olefins such as vinyl chloride and vinylidene chloride; diene monomers such as butadiene, isoprene, and chloroprene; aromatic vinyl monomers such as styrene, α-methylstyrene, p-methylstyrene, p-chlorostyrene, and p-methoxystyrene; cyano-containing vinyl monomers such as (meth)acrylonitrile and vinylidene cyanide; (meth)acrylamides such as (meth)acrylamide, N,N-dimethyl(meth)acrylamide, and N,N-dihydroxymethyl(meth)acrylamide; heteroatom-containing alicyclic vinyl monomers such as (meth)acryloylmorpholine, N-vinylpyrrolidone, and N-vinylcaprolactam; and the like.

[0121] Examples of the alkyl (meth)acrylate include compounds other than the monomer constituting the structural unit (a2-2), such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate (n-propyl (meth)acrylate, isopropyl (meth)acrylate), and the like.

[0122] Examples of the hydroxyl group-containing monomer include hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate.

[0123] The carbon number of the alkyl group of the hydroxyalkyl (meth)acrylate is preferably 1 to 10, more preferably 1 to 8, further preferably 1 to 6, and further preferably 2 to 4. The alkyl group may be a linear or branched chain group.

[0124] Examples of the epoxy group-containing monomer include epoxy group-containing (meth)acrylates such as glycidyl (meth)acrylate, β-methyl glycidyl (meth)acrylate, (3,4-epoxycyclohexyl)methyl (meth)acrylate, and 3-epoxycyclo-2-hydroxypropyl (meth)acrylate; glycidyl crotonate, and allyl glycidyl ether.

[0125] Examples of the alicyclic structure-containing monomer include cycloalkyl (meth)acrylates such as cyclopropyl (meth)acrylate, cyclobutyl (meth)acrylate, cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, cycloheptyl (meth)acrylate, and cyclooctyl (meth)acrylate, isobornyl (meth)acrylate, and dicyclopentenyl (meth)acrylate.

[0126] In addition, the resin (A2a) used in one embodiment of the present invention may be a resin having a structural unit derived from adamantyl (meth)acrylate as a structural unit derived from an alicyclic structure-containing monomer. This resin belongs to the resin (A2a) and also belongs to the resin (A2b) described later.

[0127] Furthermore, the resin (A2a) used in one embodiment of the present invention may have structural units derived from monomers selected from esters of compounds having two or more hydroxyl groups in the molecule such as dihydric or higher polyols, polyether diols, polyester diols, and (meth)acrylic acid, adducts of compounds having two or more epoxy groups in the molecule represented by epoxy resins and (meth)acrylic acid, and condensates of compounds having two or more amino groups in the molecule and (meth)acrylic acid.

[0128] Examples of such monomers include (poly)alkylene glycol (derivative) di(meth)acrylates such as ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, N,N'-methylenebis(meth)acrylamide, di(meth)acrylates of ethylene glycol adducts or propylene glycol adducts of bisphenol A, and epoxy (meth)acrylates such as (meth)acrylic acid adducts of diglycidyl ether of bisphenol A.

[0129] The weight average molecular weight (Mw) of the resin (A2a) used in one embodiment of the present invention is preferably 400 to 50,000, more preferably 1,000 to 40,000, further preferably 1,000 to 30,000, and further preferably 1,000 to 25,000.

[0130] The resin (A2) used in one embodiment of the present invention may also be a resin (A2b) comprising a structural unit (b2-1) having an adamantane structure, preferably a structural unit that decomposes under the action of an acid to form an acidic functional group. In addition, from the perspective of solubility in a solvent and adhesion to a substrate, a copolymer comprising a structural unit (b2-1) and a structural unit (b2-2) having a lactone structure is preferably used in practice.

[0131] However, at least one of the hydrogen atoms bonded to the carbon atom constituting the adamantane structure of the structural unit (b2-1) may be substituted by a substituent R.

[0132] Similarly, at least one of the hydrogen atoms bonded to the carbon atom constituting the lactone structure of the structural unit (b2-2) may be substituted with a substituent R.

[0133] Examples of the substituent R include an alkyl group having 1 to 6 carbon atoms, a hydroxyalkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), a deuterium atom, a hydroxyl group, an amino group, a nitro group, a cyano group, and a group represented by the following formula (i) or (ii).

[0134]

[0135] In the above formulae (i) and (ii), R a and R b Each is independently an alkyl group having 1 to 6 carbon atoms, a hydroxyalkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 6 carbon atoms.

[0136] m is an integer of 1-10, preferably an integer of 1-6, more preferably an integer of 1-3, and further preferably an integer of 1-2.

[0137] A is an alkylene group having 1 to 6 carbon atoms (preferably 1 to 4 carbon atoms, more preferably 2 to 3 carbon atoms).

[0138] Examples of the alkylene group include a methylene group, an ethylene group, an n-propylene group, an isopropylene group, a 1,4-butylene group, a 1,3-butylene group, a tetramethylene group, a 1,5-pentylene group, a 1,4-pentylene group, and a 1,3-pentylene group.

[0139] In addition, in the resin (A2b) used in one embodiment of the present invention, the content of the structural unit (b2-1α) having a hydroxyl-substituted adamantane structure as the structural unit (b2-1) is preferably less than 50 mol%, more preferably less than 44 mol%, further preferably less than 39 mol%, and further preferably less than 34 mol%, relative to the total amount of structural units (100 mol%) of the resin (A2b).

[0140] In one embodiment of the present invention, the structural unit (b2-1) is preferably a structural unit (b2-1-1) represented by the following formula (b2-1-i) or a structural unit (b2-1-2) represented by the following formula (b2-1-ii).

[0141]

[0142] In the above formula, n is each independently an integer of 0 to 14, preferably an integer of 0 to 4, more preferably an integer of 0 to 2, and further preferably an integer of 0 to 1.

[0143] Rx Each is independently a hydrogen atom or a methyl group.

[0144] R is independently a substituent R which the adamantane structure may have, and specifically, as described above, is preferably an alkyl group having 1 to 6 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms.

[0145] X 1 Each independently represents a single bond, an alkylene group having 1 to 6 carbon atoms, or a divalent linking group represented by any of the following formulas.

[0146]

[0147] In the above formula, *1 represents the bonding position to the oxygen atom in the above formula (b2-1-i) or (b2-1-ii), and *2 represents the bonding position to the carbon atom of the adamantane structure. 1 It represents an alkylene group having 1 to 6 carbon atoms.

[0148] In addition, in one embodiment of the present invention, the structural unit (b2-2) is preferably any structural unit among the structural unit (b2-2-1) represented by the following formula (b2-2-i), the structural unit (b2-2-2) represented by the following formula (b2-2-ii), and the structural unit (b2-2-3) represented by the following formula (b2-2-iii).

[0149]

[0150] In the above formula, n1 is an integer of 0-5, preferably an integer of 0-2, and more preferably an integer of 0-1.

[0151] n2 is an integer of 0-9, preferably an integer of 0-2, and more preferably an integer of 0-1.

[0152] n3 is an integer of 0-9, preferably an integer of 0-2, and more preferably an integer of 0-1.

[0153] R y A hydrogen atom or a methyl group.

[0154] R is independently a substituent R that the lactone structure may have, and specifically, as described above, is preferably an alkyl group having 1 to 6 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms. When there are multiple Rs, the multiple Rs may be the same group or different groups.

[0155] X 2 It is a single bond, an alkylene group having 1 to 6 carbon atoms, or a divalent linking group represented by any of the following formulas.

[0156]

[0157] In the above formula, *1 represents the bonding position to the oxygen atom in the above formula (b2-2-i), (b2-2-ii) or (b2-2-iii), and *2 represents the bonding position to the carbon atom of the lactone structure. 1 It represents an alkylene group having 1 to 6 carbon atoms.

[0158] Furthermore, the resin (A2b) used in one embodiment of the present invention may have other structural units in addition to the structural units (b2-1) and (b2-2).

[0159] As such other structural units, there can be mentioned structural units derived from (meth) alkyl acrylates; hydroxyl-containing monomers; epoxy-containing monomers; alicyclic structure-containing monomers; olefins such as ethylene, propylene, and isobutylene; halogenated olefins such as vinyl chloride and vinylidene chloride; diene monomers such as butadiene, isoprene, and chloroprene; styrene, α-methylstyrene, vinyltoluene, acrylonitrile, (meth)acrylamide, (meth)acrylonitrile, (meth)acryloylmorpholine, N-vinylpyrrolidone, and the like. The details of these monomers are the same as those described for resin (A2a).

[0160] In the resin (A2b) used in one embodiment of the present invention, the total content of the structural units (b2-1) and (b2-2) is preferably 30 to 100 mol %, more preferably 50 to 100 mol %, further preferably 70 to 100 mol %, further preferably 80 to 100 mol %, and particularly preferably 90 to 100 mol % relative to the total amount (100 mol %) of the structural units of the resin (A2b).

[0161] The weight average molecular weight (Mw) of the resin (A2b) used in one embodiment of the present invention is preferably 400 to 50,000, more preferably 2,000 to 40,000, further preferably 3,000 to 30,000, and further preferably 4,000 to 20,000.

[0162] The molecular weight distribution (Mw / Mn) of the resin (A2b) is preferably 6.0 or less, more preferably 5.0 or less, further preferably 4.0 or less, further preferably 3.2 or less, and is preferably 1.01 or more, more preferably 1.05 or more, further preferably 1.1 or more.

[0163] The resin (A2) used in one embodiment of the present invention may be a resin (A2c) (but excluding resin (A2a) and resin (A2b)) having any two or more structural units of a structural unit (a2-1) derived from a compound containing a phenolic hydroxyl group, a structural unit (a2-2) that can be decomposed by the action of an acid, an alkali or heat to form an acidic functional group, a structural unit (b2-1) having an adamantane structure and a structural unit (b2-2) having a lactone structure. The resin (A2c) is not particularly limited, and a known resin can be used, for example, the resins listed in the book "40 Years of Lithography" ("40 Years of Lithography Technology"), International Patent Gazette No. 2014-175275, International Patent Gazette No. 2015-115613, International Patent Gazette No. 2020-137935, International Patent Gazette No. 2021-029395, and International Patent Gazette No. 2021-029396 can be used.

[0164] The weight average molecular weight (Mw) of the resin (A2c) used in one embodiment of the present invention is preferably 500 to 50,000, more preferably 2,000 to 40,000, further preferably 3,000 to 30,000, and further preferably 4,000 to 20,000.

[0165] The molecular weight distribution (Mw / Mn) of the resin (A2c) is preferably 6.0 or less, more preferably 5.0 or less, further preferably 4.0 or less, further preferably 3.2 or less, and is preferably 1.01 or more, more preferably 1.05 or more, further preferably 1.1 or more.

[0166] [High carbon type resin (A3)]

[0167] The high carbon type resin (A3) used in one embodiment of the present invention is a resin in which the weight of carbon atoms contained in the resin exceeds 60% of the weight of all elements. Among them, the resin having a carbon atom weight exceeding 70% is preferred, more preferably exceeding 80%, and further preferably exceeding 90%. As a specific example of the high carbon type resin (A3), there is no particular limitation, and examples thereof include known resins described in International Publication No. 2020 / 145406.

[0168] The weight average molecular weight (Mw) of the resin (A3) used in one embodiment of the present invention is preferably 400 to 50,000, more preferably 2,000 to 40,000, further preferably 3,000 to 30,000, and further preferably 4,000 to 20,000.

[0169] The molecular weight distribution (Mw / Mn) of the resin (A3) is preferably 6.0 or less, more preferably 5.0 or less, further preferably 4.0 or less, further preferably 3.2 or less, and is preferably 1.01 or more, more preferably 1.05 or more, further preferably 1.1 or more.

[0170] [Silicon-containing resin (A4)]

[0171] The silicon-containing resin (A4) used in one embodiment of the present invention is not particularly limited as long as it is a resin containing a silicon atom, and examples thereof include known resins described in JP-A-2007-226170 and JP-A-2007-226204.

[0172] The weight average molecular weight (Mw) of the resin (A4) used in one embodiment of the present invention is preferably 400 to 50,000, more preferably 2,000 to 40,000, further preferably 3,000 to 30,000, and further preferably 4,000 to 20,000.

[0173] The molecular weight distribution (Mw / Mn) of the resin (A4) is preferably 6.0 or less, more preferably 5.0 or less, further preferably 4.0 or less, further preferably 3.2 or less, and is preferably 1.01 or more, more preferably 1.05 or more, further preferably 1.1 or more.

[0174] <Component (B): Solvent>

[0175] The resist auxiliary film composition according to one embodiment of the present invention contains a solvent (B) containing a compound (B1) represented by the following general formula (b-1).

[0176] The compound (B1) may be used alone or in combination of two or more.

[0177]

[0178] In the above formula (b-1), R 0 is an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an acyl group having 1 to 10 carbon atoms, R 1 It is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.

[0179] In one embodiment of the present invention, R in the above general formula (b-1) 0 Preferred are methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, cyclopropyl, cyclopentyl, cyclohexyl, phenyl, naphthyl, formyl, acetyl, propionyl or benzoyl, more preferably methyl, acetyl or formyl.

[0180] In one embodiment of the present invention, R in the above general formula (b-1) 1 It is preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group or a tert-butyl group, and more preferably a methyl group, an isopropyl group, an n-butyl group or an isobutyl group.

[0181] However, in one embodiment of the present invention, from the perspective of being able to form a thick film and being able to be used at a high temperature and improving the in-plane uniformity, the above-mentioned solvent (B) preferably does not contain methyl 2-methoxyisobutyrate (MBM), methyl 2-formyloxyisobutyrate (FBM) and methyl 2-acetoxyisobutyrate (ABM).

[0182] In the resist auxiliary film composition according to one embodiment of the present invention, the component (B) preferably contains a compound represented by the following general formula (b-2) as a solvent (B2) other than the compound (B1).

[0183]

[0184] In the above formula (b-2), R 1 It is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. The alkyl group may be a linear alkyl group or a branched alkyl group.

[0185] As R 1 The optional alkyl group includes, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl or tert-butyl, pentyl, hexyl, heptyl, octyl, 2-ethylhexyl, nonyl, decyl and the like.

[0186] Among these, in one embodiment of the present invention, R in the above general formula (b-2) 1 Preferred is a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group or a tert-butyl group.

[0187] In particular, it is preferred that the solvent (B) contain at least one selected from methyl 2-hydroxyisobutyrate (HBM) and 2-hydroxyisobutyric acid as the solvent (B2).

[0188] In addition, in the resist auxiliary film composition of one embodiment of the present invention, as the solvent (B2), for example, lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl n-amyl ketone, methyl isoamyl ketone, 2-heptanone, etc.; polyols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol; compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, dipropylene glycol monoacetate; monoalkyl ethers or monophenyl ethers such as monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether, etc. of the above polyols such as 1-methoxy-2-propanol or the above compounds having an ester bond, etc. Compounds having an ether bond; cyclic ethers such as dioxane; esters other than compound (B1) such as methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl β-methoxyisobutyrate, methyl methoxypropionate, ethyl ethoxypropionate, methyl β-formyloxyisobutyrate, methyl 3-hydroxyisobutyrate; aromatic organic solvents such as anisole, ethyl benzyl ether, tolyl methyl ether, diphenyl ether, dibenzyl ether, phenethyl ether, butylphenyl ether, ethylbenzene, diethylbenzene, pentylbenzene, isopropylbenzene, toluene, xylene, cymene, mesitylene, etc.; dimethyl sulfoxide (DMSO), etc.

[0189] These solvents (B2) may be used alone or in combination of two or more.

[0190] Among them, from the perspective of preparing a photoresist auxiliary film material capable of forming a thick resist auxiliary film, in the resist auxiliary film composition of the present invention, the content ratio of the compound (B1) in the component (B) is preferably 20 to 100 mass %, more preferably 30 to 100 mass %, further preferably 50 to 100 mass %, further preferably 60 to 100 mass %, and particularly preferably 70 to 100 mass % relative to the total amount (100 mass %) of the component (B) contained in the resist auxiliary film composition.

[0191] In addition, in the anti-etching auxiliary film composition of one embodiment of the present invention, the content of compound (B1), based on the total amount (100 mass%) of the solvent (B), is preferably 66.67 mass% or more from the perspective of achieving thick film thickness of the anti-etching auxiliary film composition and being able to be used at high temperatures; from the perspective of improving the in-plane uniformity of the anti-etching auxiliary film, it is more preferably 80 mass% or more; from the perspective of the storage stability of the anti-etching auxiliary film composition, it is further preferably 90 mass% or more; from the perspective of improving the solubility of the effective ingredients of the anti-etching auxiliary film, it is further preferably 99 mass% or more; from the perspective of suppressing defects in the anti-etching auxiliary film, it is particularly preferably 99.9 mass% or more.

[0192] In addition, in the component (B) used in one embodiment of the present invention, as a solvent (B2), from the perspective of solubility of the acid generator used in the resist auxiliary film composition, it is preferred to contain one or more selected from methyl 3-hydroxyisobutyrate and 1-methoxy-2-propanol. From the perspective of being able to obtain a coating film with a good surface state under high temperature baking, it is preferred to contain methyl 3-hydroxyisobutyrate. From the perspective of being able to obtain a coating film with high in-plane uniformity, it is preferred to contain 1-methoxy-2-propanol.

[0193] The method for mixing methyl 3-hydroxyisobutyrate or 1-methoxy-2-propanol is not particularly limited, and methyl 3-hydroxyisobutyrate or 1-methoxy-2-propanol may be added to compound (B1), or generated or mixed as a by-product in the production process of compound (B1) and mixed.

[0194] The content of the solvent (B2) is not limited, but is preferably less than 100% by mass, more preferably less than 50% by mass, less than 40% by mass, less than 30% by mass, less than 20% by mass, less than 10% by mass, less than 5% by mass, less than 1% by mass, more preferably less than 0.1% by mass, and particularly preferably less than 0.01% by mass, based on the total amount (100% by mass) of the resist auxiliary film composition, from the perspective of improving productivity by shortening the drying time of the coating film. It is preferably 0.0001% by mass or more, and more preferably 0.001% by mass or more from the perspective of improving the storage stability of the resist auxiliary film composition; from the perspective of improving the solubility of the active ingredients of the resist auxiliary film composition, it is more preferably 0.001% by mass or more; and from the perspective of suppressing defects in the resist auxiliary film, it is more preferably 0.01% by mass or more.

[0195] The content of the solvent (B2) is preferably 100% by mass or less, based on the total amount (100% by mass) of the compound (B1), from the perspective of improving productivity by shortening the drying time of the resist auxiliary film composition, more preferably 50% by mass or less, 40% by mass or less, 30% by mass or less, 20% by mass or less, 10% by mass or less, 5% by mass or less, 1% by mass or less, further preferably 0.1% by mass or less, and particularly preferably 0.01% by mass or less. From the perspective of improving the storage stability of the resist auxiliary film composition, it is preferably 0.0001% by mass or more; from the perspective of improving the solubility of the active ingredient of the resist auxiliary film composition, it is more preferably 0.001% by mass or more; from the perspective of suppressing defects in the resist auxiliary film, it is further preferably 0.01% by mass or more.

[0196] In addition, the content of 1-methoxy-2-propanol is preferably 1 to 98% by mass, more preferably 16 to 98% by mass, based on the total amount (100% by mass) of the resist auxiliary film composition, from the viewpoint of in-plane uniformity of the coating film. In addition, the content of 1-methoxy-2-propanol is preferably 1 to 99% by mass, more preferably 30 to 99% by mass, based on the total amount (100% by mass) of the compound (B1).

[0197] In the anti-etching auxiliary film composition of the present invention, the content of component (B) can be appropriately set according to the application, and can be set to 50 mass% or more, 54 mass% or more, 58 mass% or more, 60 mass% or more, 65 mass% or more, 69 mass% or more, 74 mass% or more, 77 mass% or more, 80 mass% or more, 82 mass% or more, 84 mass% or more, 88 mass% or more, 90 mass% or more, 94 mass% or more or 97 mass% or more, based on the total amount (100 mass%) of the anti-etching auxiliary film composition.

[0198] In addition, the upper limit of the content of component (B) can be appropriately set corresponding to the content of component (A), and can be set to less than 99 mass%, less than 98 mass%, less than 96 mass%, less than 93 mass%, less than 91 mass%, less than 86 mass%, less than 81 mass%, less than 76 mass%, less than 71 mass%, less than 66 mass% or less than 61 mass%, based on the total amount (100 mass%) of the anti-etching auxiliary film composition.

[0199] Furthermore, the content of the component (B) can be appropriately selected from each of the above upper limit and lower limit options and can be set in any combination.

[0200] <Component (C): additive selected from photosensitizers and acid generators>

[0201] The resist auxiliary film composition according to one embodiment of the present invention preferably contains at least one additive (C) selected from the group consisting of a photosensitizer and an acid generator.

[0202] Furthermore, the component (C) may be used alone or in combination of two or more.

[0203] In the resist auxiliary film composition of one embodiment of the present invention, the content of component (C) is preferably 0.01 to 80 parts by mass, more preferably 0.05 to 65 parts by mass, further preferably 0.1 to 50 parts by mass, and further preferably 0.5 to 30 parts by mass, relative to 100 parts by mass of the resin (A) contained in the resist auxiliary film composition.

[0204] Hereinafter, the photosensitizer and the acid generator contained as the component (C) will be described.

[0205] [Photosensitive agent]

[0206] The above-mentioned photosensitizer which can be optionally used as component (C) is not particularly limited as long as it is a substance generally used as a photosensitive component in a resist auxiliary film composition. A substance used in a resist composition may also be used.

[0207] The photosensitizers may be used alone or in combination of two or more.

[0208] Examples of the photosensitizer used in one embodiment of the present invention include reaction products of an acid chloride and a compound having a functional group (hydroxyl group, amino group, etc.) capable of condensing with the acid chloride.

[0209] Examples of the acid chloride include naphthoquinonediazidesulfonyl chloride and benzoquinonediazidesulfonyl chloride, and specific examples include 1,2-naphthoquinonediazide-5-sulfonyl chloride and 1,2-naphthoquinonediazide-4-sulfonyl chloride.

[0210] Examples of the compound having a functional group that can condense with an acid chloride include hydroquinone, resorcinol, 2,4-dihydroxybenzophenone, 2,3,4-trihydroxybenzophenone, 2,4,6-trihydroxybenzophenone, 2,4,4'-trihydroxybenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, and 2,2',3,4,6'-pentahydroxybenzophenone. Hydroxybenzophenones, bis(2,4-dihydroxyphenyl)methane, bis(2,3,4-trihydroxyphenyl)methane, bis(2,4-dihydroxyphenyl)propane and other hydroxyphenylalkanes, 4,4',3",4"-tetrahydroxy-3,5,3',5'-tetramethyltriphenylmethane, 4,4',2",3",4"-pentahydroxy-3,5,3',5'-tetramethyltriphenylmethane and other hydroxytriphenylmethanes, etc.

[0211] As the photosensitizer used in one embodiment of the present invention, commercially available products such as "DTEP-350" (a diazonaphthoquinone-type photosensitizer manufactured by Daito Chemical Industry Co., Ltd.) can be used.

[0212] [Acid generator]

[0213] The acid generator which can be optionally used as component (C) may be any compound that can directly or indirectly generate an acid by heating or irradiation with radiation such as visible light, ultraviolet light, excimer laser, electron beam, extreme ultraviolet light (EUV), X-ray, and ion beam.

[0214] As a specific suitable acid generator, a compound represented by any one of the following general formulae (c-1) to (c-8) is preferred.

[0215] (Compound represented by general formula (c-1))

[0216]

[0217] In the above formula (c-1), R 13 Each is independently a hydrogen atom, a linear, branched or cyclic alkyl group, a linear, branched or cyclic alkoxy group, a hydroxyl group or a halogen atom.

[0218] X - It is a sulfonate ion or a halide ion having an alkyl group, an aryl group, a halogenated alkyl group or a halogenated aryl group.

[0219] The compound represented by the general formula (c-1) is preferably selected from triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium nonafluoro-n-butanesulfonate, diphenyltolylsulfonium nonafluoro-n-butanesulfonate, triphenylsulfonium perfluoro-n-octanesulfonate, diphenyl-4-methylphenylsulfonium trifluoromethanesulfonate, di-2,4,6-trimethylphenylsulfonium trifluoromethanesulfonate, diphenyl-4-tert-butoxyphenylsulfonium trifluoromethanesulfonate, diphenyl-4-tert-butoxyphenylsulfonium nonafluoro-n-butanesulfonate, diphenyl-4-hydroxyphenylsulfonium trifluoromethanesulfonate, bis(4-fluorophenyl)-4-hydroxyphenylsulfonium trifluoromethanesulfonate, diphenyl-4-hydroxyphenylsulfonium nonafluoro-n-butanesulfonate, bis(4-hydroxyphenyl)-phenylsulfonium trifluoromethanesulfonate, tris(4-methoxyphenyl)sulfonium trifluoromethanesulfonate, At least one of tri(4-fluorophenyl)sulfonium trifluoromethanesulfonate, triphenylsulfonium p-toluenesulfonate, triphenylsulfonium benzenesulfonate, diphenyl-2,4,6-trimethylphenyl p-toluenesulfonate, diphenyl-2,4,6-trimethylphenylsulfonium-2-trifluoromethylbenzenesulfonate, diphenyl-2,4,6-trimethylphenylsulfonium-4-trifluoromethylbenzenesulfonate, diphenyl-2,4,6-trimethylphenylsulfonium-2,4-difluorobenzenesulfonate, diphenyl-2,4,6-trimethylphenylsulfonium hexafluorobenzenesulfonate, diphenylnaphthylsulfonium trifluoromethanesulfonate, diphenyl-4-hydroxyphenylsulfonium p-toluenesulfonate, triphenylsulfonium-10-camphorsulfonate, diphenyl-4-hydroxyphenylsulfonium-10-camphorsulfonate and cyclo(1,3-perfluoropropanedisulfon)imide salts.

[0220] (Compound represented by general formula (c-2))

[0221]

[0222] In the above formula (c-2), R 14 Each is independently a hydrogen atom, a linear, branched or cyclic alkyl group, a linear, branched or cyclic alkoxy group, a hydroxyl group or a halogen atom.

[0223] X - It is a sulfonate ion or a halide ion having an alkyl group, an aryl group, a halogenated alkyl group or a halogenated aryl group.

[0224] The compound represented by the general formula (c-2) is preferably selected from bis(4-tert-butylphenyl)iodide Trifluoromethanesulfonate, bis(4-tert-butylphenyl)iodide Nonafluorobutane sulfonate, bis(4-tert-butylphenyl) iodide Perfluorooctane sulfonate, bis(4-tert-butylphenyl) iodide p-Toluenesulfonate, bis(4-tert-butylphenyl)iodide Benzenesulfonate, bis(4-tert-butylphenyl)iodide -2-Trifluoromethylbenzenesulfonate, bis(4-tert-butylphenyl)iodide -4-Trifluoromethylbenzenesulfonate, bis(4-tert-butylphenyl)iodide -2,4-Difluorobenzenesulfonate, bis(4-tert-butylphenyl)iodide Hexafluorobenzenesulfonate, bis(4-tert-butylphenyl)iodide -10-Camphorsulfonate, diphenyl iodide Trifluoromethanesulfonate, diphenyl iodide Nonafluorobutane sulfonate, diphenyl iodide Perfluorooctane sulfonate, diphenyl iodide p-Toluenesulfonate, diphenyl iodide Benzenesulfonate, diphenyl iodide -10-Camphorsulfonate, diphenyl iodide -2-Trifluoromethylbenzenesulfonate, diphenyl iodide -4-Trifluoromethylbenzenesulfonate, diphenyl iodide -2,4-Difluorobenzenesulfonate, diphenyl iodide Hexafluorobenzenesulfonate, bis(4-trifluoromethylphenyl)iodide Trifluoromethanesulfonate, bis(4-trifluoromethylphenyl)iodide Nonafluorobutane sulfonate, bis(4-trifluoromethylphenyl) iodide Perfluorooctane sulfonate, bis(4-trifluoromethylphenyl) iodide p-Toluenesulfonate, bis(4-trifluoromethylphenyl)iodide Benzenesulfonate and bis(4-trifluoromethylphenyl)iodide -10-camphorsulfonate.

[0225] (Compound represented by general formula (c-3))

[0226]

[0227] In the above formula (c-3), Q is an alkylene group, an arylene group or an alkyleneoxy group. 15 is an alkyl group, an aryl group, a halogenated alkyl group or a halogenated aryl group.

[0228] The compound represented by the general formula (c-3) is preferably selected from N-(trifluoromethylsulfonyloxy)succinimide, N-(trifluoromethylsulfonyloxy)phthalimide, N-(trifluoromethylsulfonyloxy)diphenylmaleimide, N-(trifluoromethylsulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboximide, N-(trifluoromethylsulfonyloxy)naphthalimide, N-(10-camphorsulfonyloxy)succinimide, N-(10-camphorsulfonyloxy)phthalimide, N-(1 0-camphorsulfonyloxy)diphenylmaleimide, N-(10-camphorsulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboximide, N-(10-camphorsulfonyloxy)naphthalene dicarboximide, N-(n-octanesulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboximide, N-(n-octanesulfonyloxy)naphthalene dicarboximide, N-(p-toluenesulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboximide, N-(p-toluenesulfonyloxy)naphthalene dicarboximide carboximide, N-(2-trifluoromethylbenzenesulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboximide, N-(2-trifluoromethylbenzenesulfonyloxy)naphthalene dicarboximide, N-(4-trifluoromethylbenzenesulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboximide, N-(4-trifluoromethylbenzenesulfonyloxy)naphthalene dicarboximide, N-(perfluorobenzenesulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboximide, N-(perfluorobenzenesulfonyloxy)naphthalene dicarboximide at least one of imide, N-(1-naphthalenesulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboximide, N-(1-naphthalenesulfonyloxy)naphthalene dicarboximide, N-(nonafluoro-n-butanesulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboximide, N-(nonafluoro-n-butanesulfonyloxy)naphthalene dicarboximide, N-(perfluoro-n-octanesulfonyloxy)bicyclo[2.2.1]hept-5-ene-2,3-dicarboximide and N-(perfluoro-n-octanesulfonyloxy)naphthalene dicarboximide.

[0229] (Compound represented by general formula (c-4))

[0230]

[0231] In the above formula (c-4), R 16 Each is independently a linear, branched or cyclic alkyl group, aryl group, heteroaryl group or aralkyl group, and at least one hydrogen atom in these groups may be substituted by any substituent.

[0232] As the compound represented by the above-mentioned general formula (c-4), it is preferably selected from at least one of diphenyl disulfone, di(4-methylphenyl) disulfone, dinaphthyl disulfone, di(4-tert-butylphenyl) disulfone, di(4-hydroxyphenyl) disulfone, di(3-hydroxynaphthyl) disulfone, di(4-fluorophenyl) disulfone, di(2-fluorophenyl) disulfone and di(4-trifluoromethylphenyl) disulfone.

[0233] (Compound represented by general formula (c-5))

[0234]

[0235] In the above formula (c-5), R 17 Each is independently a linear, branched or cyclic alkyl group, aryl group, heteroaryl group or aralkyl group, and at least one hydrogen atom in these groups may be substituted by any substituent.

[0236] As the compound represented by the above-mentioned general formula (c-5), it is preferably selected from at least one of α-(methylsulfonyloxyimino)benzyl acetonitrile, α-(methylsulfonyloxyimino)-4-methoxybenzyl acetonitrile, α-(trifluoromethylsulfonyloxyimino)benzyl acetonitrile, α-(trifluoromethylsulfonyloxyimino)-4-methoxybenzyl acetonitrile, α-(ethylsulfonyloxyimino)-4-methoxybenzyl acetonitrile, α-(propylsulfonyloxyimino)-4-methylbenzyl acetonitrile and α-(methylsulfonyloxyimino)-4-bromobenzyl acetonitrile.

[0237] (Compound represented by general formula (c-6))

[0238]

[0239] In the above formula (c-6), R 18 Each independently represents a halogenated alkyl group having one or more chlorine atoms and one or more bromine atoms. The halogenated alkyl group preferably has 1 to 5 carbon atoms.

[0240] (Compounds represented by general formula (c-7) and (c-8))

[0241]

[0242] In the above formulas (c-7) and (c-8), R 19 and R 20 Each is independently an alkyl group having 1 to 3 carbon atoms (such as methyl, ethyl, n-propyl, isopropyl, etc.), a cycloalkyl group having 3 to 6 carbon atoms (such as cyclopentyl, cyclohexyl, etc.), an alkoxy group having 1 to 3 carbon atoms (such as methoxy, ethoxy, propoxy, etc.), or an aryl group having 6 to 10 carbon atoms (such as phenyl, tolyl, naphthyl), preferably an aryl group having 6 to 10 carbon atoms.

[0243] L19 and L 20 Each is independently an organic group having a 1,2-naphthoquinonediazide group, and specifically preferably a 1,2-quinonediazidesulfonyl group such as a 1,2-naphthoquinonediazide-4-sulfonyl group, a 1,2-naphthoquinonediazide-5-sulfonyl group, or a 1,2-naphthoquinonediazide-6-sulfonyl group, and more preferably a 1,2-naphthoquinonediazide-4-sulfonyl group or a 1,2-naphthoquinonediazide-5-sulfonyl group.

[0244] p is an integer from 1 to 3, q ​​is an integer from 0 to 4, and 1≤p+q≤5.

[0245] J 19 It is a single bond, an alkylene group having 1 to 4 carbon atoms, a cycloalkylene group having 3 to 6 carbon atoms, a phenylene group, a group represented by the following formula (c-7-i), a carbonyl group, an ester group, an amide group or -O-.

[0246] Y 19 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 10 carbon atoms, and X 20 Each is independently a group represented by the following formula (c-8-i).

[0247]

[0248] In the above formula (c-8-i), Z 22 Each R is independently an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, or an aryl group having 6 to 10 carbon atoms. 22 Each independently represents an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms; and r is an integer of 0-3.

[0249] As the acid generator used in one embodiment of the present invention, other acid generators other than the compound represented by any one of the above general formulae (c-1) to (c-8) may be used.

[0250] Examples of such other acid generators include bis(p-toluenesulfonyl)diazomethane, bis(2,4-dimethylphenylsulfonyl)diazomethane, bis(tert-butylsulfonyl)diazomethane, bis(n-butylsulfonyl)diazomethane, bis(isobutylsulfonyl)diazomethane, bis(isopropylsulfonyl)diazomethane, bis(n-propylsulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, bis(isopropylsulfonyl)diazomethane, 1,3-bis(cyclohexylsulfonylazomethylsulfonyl)propane, 1,4-bis(phenylsulfonyl)diazomethane, Bissulfonyldiazomethanes such as 1,6-bis(phenylsulfonylazomethylsulfonyl)butane, 1,10-bis(cyclohexylsulfonylazomethylsulfonyl)decane, halogen-containing triazine derivatives such as 2-(4-methoxyphenyl)-4,6-(bistrichloromethyl)-1,3,5-triazine, 2-(4-methoxynaphthyl)-4,6-(bistrichloromethyl)-1,3,5-triazine, tris(2,3-dibromopropyl)-1,3,5-triazine and tris(2,3-dibromopropyl)isocyanurate, etc.

[0251] <Other additives>

[0252] The resist auxiliary film composition according to one embodiment of the present invention may further contain other components in addition to the above-mentioned components (A) to (C).

[0253] Examples of other components include at least one selected from an acid crosslinking agent, an acid diffusion control agent, a dissolution accelerator, a dissolution control agent, a sensitizer, a surfactant, an organic carboxylic acid, or an oxyacid of phosphorus or a derivative thereof.

[0254] Furthermore, the content of each of these other components can be appropriately selected depending on the type of component and the type of resin (A), and is preferably 0.001 to 100 parts by mass, more preferably 0.01 to 70 parts by mass, further preferably 0.1 to 50 parts by mass, and further preferably 0.3 to 30 parts by mass, relative to 100 parts by mass of the resin (A) contained in the resist auxiliary film composition.

[0255] (Acid crosslinking agent)

[0256] The acid crosslinking agent may be any compound having a crosslinkable group capable of crosslinking with the resin (A), and may be appropriately selected according to the type of the resin (A).

[0257] As the acid cross-linking agent used in one embodiment of the present invention, for example, methylol-containing melamine compounds, methylol-containing benzoguanamine compounds, methylol-containing urea compounds, methylol-containing glycoluril compounds, methylol-containing phenol compounds and other hydroxymethyl-containing compounds; alkoxyalkyl-containing compounds such as alkoxyalkyl-containing melamine compounds, alkoxyalkyl-containing benzoguanamine compounds, alkoxyalkyl-containing urea compounds, alkoxyalkyl-containing glycoluril compounds, alkoxyalkyl-containing phenol compounds and other alkoxyalkyl-containing compounds; carboxymethyl-containing compounds such as carboxymethyl-containing melamine compounds, carboxymethyl-containing benzoguanamine compounds, carboxymethyl-containing urea compounds, carboxymethyl-containing glycoluril compounds, carboxymethyl-containing phenol compounds and other carboxymethyl-containing compounds; bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol S type epoxy compounds, novolac resin type epoxy compounds, resol type epoxy compounds, poly (hydroxystyrene) type epoxy compounds and the like can be cited.

[0258] These acid cross-linking agents may be used alone or in combination of two or more.

[0259] (Acid Diffusion Controller)

[0260] The acid diffusion controller is an additive having the function of controlling the diffusion of the acid generated by the acid generator in the resist auxiliary film, preventing an undesired chemical reaction, and the like.

[0261] The acid diffusion controller used in one embodiment of the present invention is not particularly limited, and examples thereof include nitrogen-containing basic compounds, basic sulfonium compounds, basic iodine compounds, Compounds and other radiodegradable basic compounds.

[0262] These acid diffusion controllers may be used alone or in combination of two or more.

[0263] (Dissolution accelerator)

[0264] The dissolution accelerator is an additive that has the function of improving the solubility of the resin (A) in the developer and appropriately increasing the dissolution rate of the resin (A) during development.

[0265] The dissolution accelerator used in one embodiment of the present invention is not particularly limited, and examples thereof include phenolic compounds such as bisphenols and tris(hydroxyphenyl)methane.

[0266] These dissolution promoters may be used alone or in combination of two or more.

[0267] (Dissolution Control Agent)

[0268] The dissolution control agent is an additive that has a function of controlling the solubility of the resin (A) in a developer when the solubility of the resin (A) is too high, thereby appropriately reducing the dissolution rate during development.

[0269] The dissolution control agent used in one embodiment of the present invention is not particularly limited, and examples thereof include aromatic hydrocarbons such as phenanthrene, anthracene, and acenaphthene; ketones such as acetophenone, benzophenone, and phenylnaphthyl ketone; and sulfones such as methyl phenyl sulfone, diphenyl sulfone, and dinaphthyl sulfone.

[0270] These dissolution control agents may be used alone or in combination of two or more.

[0271] (Sensitizer)

[0272] The sensitizer is an additive that absorbs the energy of irradiated radiation and transfers the energy to the acid generator to increase the amount of acid generated. It is also an additive that absorbs light of a specific wavelength.

[0273] Examples of the sensitizer used in one embodiment of the present invention include benzophenones, biacetyl compounds, pyrenes, phenothiazines, and fluorenes.

[0274] These sensitizers may be used alone or in combination of two or more.

[0275] (Surfactant)

[0276] The surfactant is an additive having the function of improving the coating property and streaks of the resist auxiliary film composition, the developability of the resist auxiliary film composition, and the like.

[0277] As the surfactant used in one embodiment of the present invention, anionic surfactants, cationic surfactants, nonionic surfactants and amphoteric surfactants are all possible, preferably nonionic surfactants. As nonionic surfactants, for example, polyoxyethylene higher alkyl ethers, polyoxyethylene higher alkylphenyl ethers, higher fatty acid diesters of polyethylene glycol, etc. can be cited.

[0278] These surfactants may be used alone or in combination of two or more.

[0279] (Organic carboxylic acid or phosphorus oxygen acid or its derivative)

[0280] The organic carboxylic acid or phosphorus oxoacid or its derivative is an additive having the function of preventing sensitivity deterioration or improving resist pattern shape, shelf stability, and the like.

[0281] The organic carboxylic acid used in one embodiment of the present invention is not particularly limited, and examples thereof include malonic acid, citric acid, malic acid, succinic acid, benzoic acid, salicylic acid, etc. In addition, examples of phosphorus oxyacids or derivatives thereof include phosphoric acid, di-n-butyl phosphate, diphenyl phosphate and other phosphoric acid or their esters and other derivatives, phosphonic acid, dimethyl phosphonate, di-n-butyl phosphonate, phenylphosphonic acid, diphenyl phosphonate, dibenzyl phosphonate and other phosphonic acid or their esters and other derivatives, and phosphinic acid, phenylphosphinic acid and other phosphinic acid and their esters and other derivatives.

[0282] These compounds may be used alone or in combination of two or more.

[0283] (Other ingredients)

[0284] The resist auxiliary film composition according to one embodiment of the present invention may contain dyes, pigments, adhesion promoters, antihalation agents, storage stabilizers, defoaming agents, shape improvers, and the like in addition to the above-mentioned other components.

[0285] [Pattern Formation Method]

[0286] In addition, one embodiment of the present invention also relates to a pattern forming method, which includes: a process (A-1) of forming a resist underlayer film on a substrate using the resist auxiliary film composition of this embodiment; a process (A-2) of forming at least one photoresist layer on the above-mentioned resist underlayer film; and after the above-mentioned process (A-2), a process (A-3) of irradiating radiation to a specified area of ​​the above-mentioned photoresist layer for development.

[0287] As described above, the resist auxiliary film composition according to one embodiment of the present invention can form a thick resist auxiliary film (here, resist underlayer film) suitable for manufacturing various devices even though the content of the effective component including the resin is limited to a predetermined value or less.

[0288] In the case of forming a photoresist underlayer film material for a spin-coated carbon film used in a double-layer resist method or a triple-layer resist method, the method includes: a step (B-1) of forming a resist underlayer film using the resist auxiliary film composition of the present embodiment; a step (B-2) of forming a resist intermediate layer film on the above-mentioned resist underlayer film; a step (B-3) of forming at least one photoresist layer on the above-mentioned resist intermediate layer film; after the above-mentioned step (B-3), a step (B-4) of irradiating radiation to a specified area of ​​the above-mentioned photoresist layer and developing to form a resist pattern; and after the above-mentioned step (B-4), a step (B-5) of etching the above-mentioned resist intermediate layer film using the above-mentioned resist pattern as a mask, etching the above-mentioned resist underlayer film using the obtained resist intermediate layer film pattern as an etching mask, and etching the substrate using the obtained resist underlayer film pattern as an etching mask to form a pattern on the substrate.

[0289] The method for forming the above-mentioned resist underlayer film is not particularly limited, as long as it is a film formed by the resist auxiliary film composition of the present embodiment, and a known method can be applied. For example, after providing the resist auxiliary film composition of the present embodiment on the substrate by a known coating method or printing method such as spin coating or screen printing, the organic solvent is removed by volatilization, etc., so that the resist underlayer film can be formed.

[0290] When forming the resist lower film, in order to suppress the occurrence of mixing with the upper resist and promote the crosslinking reaction, it is preferably baked. In this case, the baking temperature is not particularly limited, preferably in the range of 80 to 600° C., more preferably 200 to 400° C. In addition, the baking time is not particularly limited, preferably in the range of 10 to 300 seconds. In addition, the thickness of the resist lower film can be appropriately selected according to the required performance, is not particularly limited, and is generally preferably 3 to 20,000 nm, more preferably 10 to 15,000 nm, and further preferably 50 to 1,000 nm.

[0291] After the resist lower film is made on the substrate, when an anti-reflection film for KrF excimer laser or ArF excimer laser or a photoresist lower film material for EUV lithography is formed, a monolayer resist layer is preferably made thereon. In this case, a known material can be used as the photoresist material for forming the resist layer.

[0292] After the resist underlayer film is formed on the substrate, when the resist underlayer film material facing the spin-on carbon film used in the double-layer resist method or the triple-layer resist method is formed, in the case of the double-layer process, it is preferred to form a silicon-containing resist layer or a single-layer resist formed of hydrocarbons thereon; in the case of the triple-layer process, it is preferred to form a silicon-containing intermediate layer thereon and form a single-layer resist layer not containing silicon thereon. In this case, as the photoresist material for forming the resist layer, a known material can be used.

[0293] As the silicon-containing resist material for the double-layer process, from the viewpoint of oxygen etching resistance, it is preferred to use a positive photoresist material which uses a silicon-containing polymer such as a polysilsesquioxane derivative or a vinylsilane derivative as a matrix polymer and contains an organic solvent, an acid generator, and an alkaline compound as required, etc. Among them, as the silicon-containing polymer, a known polymer used in such a resist material can be used.

[0294] As a silicon-containing intermediate layer for a three-layer process, an intermediate layer based on a polysilsesquioxane matrix is ​​preferably used. By making the intermediate layer have the effect of an antireflection film, there is a tendency to effectively suppress reflection. For example, in the process for 193nm exposure, when a material containing a large number of aromatic groups and having high substrate etching tolerance is used as a resist lower film, the k value increases, and there is a tendency for the substrate reflection to increase; but by suppressing the reflection with an intermediate layer, the substrate reflection can be controlled to less than 0.5%. As an intermediate layer with such an antireflection effect, it is preferred to use a polysilsesquioxane cross-linked by acid or heat that has a phenyl group or a light-absorbing group having a silicon-silicon bond introduced for 193nm exposure, but it is not limited to this.

[0295] In addition, an intermediate layer formed by a chemical vapor deposition (CVD) method may also be used. As an intermediate layer with good effect as an anti-reflection film prepared by a CVD method, for example, a SiON film is known, but it is not limited to this. Generally, a method of forming an intermediate layer by a wet process such as a spin coating method or screen printing has the advantages of being simpler and less expensive than a CVD method. Among them, the upper layer resist in the three-layer process can be either positive or negative, and the same resist as the commonly used single-layer resist can be used.

[0296] When the resist layer is formed by the above-mentioned resist material, as in the case of forming the above-mentioned resist underlayer film, a wet process such as spin coating or screen printing is preferably used. In addition, after the resist material is applied by spin coating, pre-baking is usually performed, and the pre-baking is preferably performed at 80 to 180° C. for 10 to 300 seconds. Then, exposure is performed according to a conventional method, and post-exposure baking (PEB) and development are performed, thereby obtaining a resist pattern. Among them, the thickness of the resist film is not particularly limited, and is usually preferably 10 to 50,000 nm, more preferably 20 to 20,000 nm, and further preferably 50 to 15,000 nm.

[0297] In addition, the exposure light can be appropriately selected and used according to the photoresist material used, and is usually high-energy radiation with a wavelength of 300 nm or less, specifically, excimer lasers of 248 nm, 193 nm, and 157 nm, soft X-rays of 3 to 20 nm, electron beams, and X-rays.

[0298] The resist pattern formed by the above method has pattern collapse suppressed by the resist underlayer film of this embodiment. Therefore, by using the resist underlayer film of this embodiment, a finer pattern can be obtained, and the exposure amount required to obtain the resist pattern can be reduced.

[0299] Next, the obtained resist pattern is used as a mask for etching. As the etching of the resist lower film in the double-layer process, gas etching is preferably adopted. As the gas etching, etching using oxygen is preferably used. In addition to oxygen, inactive gases such as He and Ar, as well as CO, CO2, NH3, SO2, N2, NO2, and H2 gases can also be added. In addition, gas etching can be performed using only CO, CO2, NH3, N2, NO2, and H2 gases instead of oxygen. In particular, the latter gas is preferably used for sidewall protection to prevent drilling of the sidewalls of the pattern.

[0300] On the other hand, the etching of the middle layer in the three-layer process is also preferably carried out by gas etching. As gas etching, the same process as described in the above-mentioned two-layer process can be used. In particular, the processing of the middle layer in the three-layer process is preferably carried out using a Freon-based gas with the resist pattern as a mask. Then, the middle layer pattern can be used as a mask, and oxygen etching can be carried out, for example, to process the resist lower film.

[0301] Next, when an inorganic hard mask intermediate layer film is formed as an intermediate layer, a silicon oxide film, a silicon nitride film, and a silicon oxynitride film (SiON film) are formed by a CVD method or an ALD method. As a method for forming a nitride film, for example, the method described in Japanese Patent Publication No. 2002-334869 and WO2004 / 066377 can be used, but it is not limited thereto. A photoresist film can be directly formed on such a resist intermediate layer film, but an organic antireflective film (BARC) can also be formed on the resist intermediate layer film by spin coating, and then a photoresist film can be formed thereon.

[0302] As the intermediate layer, it is also preferred to use an intermediate layer based on polysilsesquioxane. By making the resist intermediate layer film have the effect of an antireflection film, there is a tendency to effectively suppress reflection. The specific material of the intermediate film based on polysilsesquioxane can use, for example, the materials described in Japanese Patent Publication No. 2007-226170 and Japanese Patent Publication No. 2007-226204, but is not limited thereto.

[0303] In addition, the following substrate etching can also be performed by conventional methods. For example, when the substrate is SiO2 or SiN, Freon-based gases can be used as the main body for etching; when the substrate is p-Si or Al, W, chlorine-based or bromine-based gases can be used as the main body for etching. In the case of etching the substrate using Freon-based gases, the silicon-containing resist of the double-layer resist process and the silicon-containing intermediate layer of the three-layer process are stripped while the substrate is processed. On the other hand, in the case of etching the substrate using chlorine-based or bromine-based gases, the stripping of the silicon-containing resist layer or the silicon-containing intermediate layer is performed separately, and usually dry etching stripping is performed using Freon-based gases after the substrate is processed.

[0304] The resist lower film of this embodiment has the characteristic of excellent etching tolerance of these substrates. Among them, the substrate can be appropriately selected and used from known products, without particular limitation, and examples thereof include Si, α-Si, p-Si, SiO2, SiN, SiON, W, TiN, Al, etc. In addition, the substrate can also be a laminate having a processed film (processed substrate) on a substrate (support). As such a processed film, various Low-k films such as Si, SiO2, SiON, SiN, p-Si, α-Si, W, W-Si, Al, Cu, Al-Si and their barrier films can be cited, and products of different materials from the substrate (support) are usually used. In addition, the thickness of the substrate or the processed film to be processed is not particularly limited, and is usually preferably in the range of 50 to 1000000nm, and more preferably 75 to 500000nm.

[0305] The resist auxiliary film composition of one embodiment of the present invention can also be used to form a resist intermediate layer film. Another embodiment of the pattern forming method of the present invention includes: a step (B-1) of forming a resist underlayer film on a substrate; a step (B-2) of forming a resist intermediate layer film on the resist underlayer film using the resist auxiliary film composition of an embodiment of the present invention; a step (B-3) of forming at least one photoresist layer on the resist intermediate layer film; after the step (B-3), a step (B-4) of irradiating a predetermined area of ​​the photoresist layer with radiation and developing to form a resist pattern; and after the step (B-4), a step (B-5) of etching the resist intermediate layer film using the resist pattern as a mask, etching the resist underlayer film using the obtained resist intermediate layer film pattern as an etching mask, and etching the substrate using the obtained resist underlayer film pattern as an etching mask to form a pattern on the substrate.

[0306] Example

[0307] The present invention is described below using examples, but the present invention is not limited to these examples. The measured values ​​in the examples were measured using the following methods or devices.

[0308] (1) Film thickness

[0309] The film thickness of the coating film formed from the resist auxiliary film composition was measured in a constant temperature and humidity chamber at a temperature of 23° C. and a humidity of 50% (relative humidity) using a film thickness measurement system (device name “F20”, manufactured by Filmetrics Inc.).

[0310] (2) Content ratio of the structural unit of the resin

[0311] use 13 C-NMR (model "JNM-ECA500", manufactured by JEOL Ltd., 125 MHz), using deuterated chloroform as solvent, 13 The quantitative mode of C was integrated 1024 times to measure the content ratio of the structural unit of the resin.

[0312] (3) Weight average molecular weight (Mw), number average molecular weight (Mn), and molecular weight distribution (Mw / Mn) of the resin

[0313] The Mw and Mn of the resin were measured by gel permeation chromatography (GPC) under the following conditions using polystyrene as a standard substance.

[0314] Device name: LaChrom series manufactured by Hitachi

[0315] Detector: RI detector L-2490

[0316] Column: 2 TSKgelGMHHR-M + guard column HHR-H manufactured by Tosoh Corporation

[0317] Solvent: THF (containing stabilizer)

[0318] Flow rate 1mL / min

[0319] Column temperature: 40℃

[0320] Then, the ratio of Mw to Mn (Mw / Mn) of the obtained resin was calculated as the value of the molecular weight distribution of the resin.

[0321] The solvents used in the following Examples and Comparative Examples are as follows.

[0322] <Ingredient (B1)>

[0323] ABM: methyl 2-acetoxyisobutyrate. In the above general formula (b-1), R 0 is acetyl and R 1 A compound containing methyl.

[0324] iPAIB: 2-acetoxyisobutyric acid isopropyl ester. In the above general formula (b-1), R 0 is acetyl and R 1 It is an isopropyl compound.

[0325] <Ingredient (B2)>

[0326] ·PGMEA: Propylene glycol monomethyl ether acetate

[0327] HBM: 2-Hydroxyisobutyric Acid Methyl Ester

[0328] [Resist auxiliary film composition containing novolac resin]

[0329] Examples 1a to 7a, Comparative Examples 1a to 6a

[0330] As the liquid crystal resin, cresol novolac resin EP4080G (manufactured by Asahi Organic Materials Co., Ltd.) was used.

[0331] 84 parts by mass of the above-mentioned cresol novolac resin and 16 parts by mass of a naphthoquinone diazide type photosensitizer (trade name "DTEP-350", manufactured by Daito Chemical Industry Co., Ltd.) are mixed and dissolved in a solvent of the type and proportion shown in Table 1 to prepare an anti-etching auxiliary film composition having the concentration of active ingredients (the above-mentioned cresol novolac resin and photosensitizer) recorded in Tables 1 and 2, respectively.

[0332] Then, the obtained resist auxiliary film composition was spin-coated on a silicon wafer at 1500 rpm to form a coating film, and the coating film was pre-baked at 110° C. for 90 seconds to form a resist auxiliary film. The film thickness was measured at 5 locations on the resist auxiliary film, and the average film thickness of the 5 locations was calculated as the average film thickness. The results are shown in Tables 1 and 2.

[0333] [Table 1]

[0334]

[0335] As can be seen from Table 1, the anti-etching auxiliary film composition prepared in Examples 1a to 4a can form a thicker anti-etching auxiliary film than the anti-etching auxiliary film composition of Comparative Examples 1a to 6a having the same resin component concentration. It can also be seen that the anti-etching auxiliary film composition prepared in Examples 5a to 7a can form a thicker anti-etching auxiliary film than the anti-etching auxiliary film composition of Comparative Examples 1a to 3a having the same resin component concentration. In particular, in Examples 1a to 4a, although the content of the phenolic varnish resin is as low as 20 to 25% by mass, a thick anti-etching auxiliary film can still be formed.

[0336] [Resist auxiliary film composition containing ethylenically unsaturated resin (O)]

[0337] Examples 1b to 7b, Comparative Examples 1b to 6b

[0338] As the ethylenically unsaturated resin (O), a copolymer having a structural unit of hydroxystyrene / t-butyl acrylate / styrene = 3 / 1 / 1 (molar ratio) (manufactured by Maruzen Petrochemical Co., Ltd., Mw = 12000) was used.

[0339] The above copolymers were mixed with mixed solvents of the types and blending ratios shown in Table 2 to prepare resist auxiliary film compositions having the concentrations of the active ingredient (ethylenically unsaturated resin (O)) shown in Table 2.

[0340] Then, the prepared resist auxiliary film composition was spin-coated on a silicon wafer at 1500 rpm to form a coating film, and the coating film was pre-baked at 110° C. for 90 seconds to form a resist auxiliary film. The film thickness was measured at 5 locations on the resist auxiliary film, and the average film thickness of the 5 locations was calculated as the average film thickness. The results are shown in Table 2.

[0341] [Table 2]

[0342]

[0343] As can be seen from Table 2, the resist auxiliary film compositions prepared in Examples 1b to 7b can form thicker resist auxiliary films than the resist auxiliary film compositions of Comparative Examples 1b to 6b having the same resin component concentration.

[0344] [Resist auxiliary film composition containing ethylenically unsaturated resin (O) and acid generator]

[0345] Resist auxiliary film compositions were prepared according to the formulations shown in Tables 3 and 4, and their solubility in the resins (i) to (iv) and acid generators (i) to (ii) used as raw materials shown in Tables 3 and 4 was evaluated.

[0346] <Solvent>

[0347] ABM: 2-acetoxyisobutyric acid methyl ester (synthesized according to WO2020 / 004466)

[0348] iPAIB: 2-acetoxyisobutyric acid isopropyl ester (synthesized according to WO2020 / 004466)

[0349] HBM: 2-Hydroxyisobutyric acid methyl ester (Mitsubishi Gas Chemical Co., Ltd.)

[0350] PGMEA: Propylene glycol monomethyl ether acetate (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0351] <Resin>

[0352] Resins having the following compositions (molecular weights) were synthesized by the above method.

[0353] (i) Cresol novolac resin EP4080G (manufactured by Asahi Organic Materials Co., Ltd.)

[0354] (ii) A copolymer having a structural unit of hydroxystyrene / tert-butyl acrylate / styrene = 3 / 1 / 1 (molar ratio) (manufactured by Maruzen Petrochemical Co., Ltd., Mw = 12000)

[0355] (iii) A copolymer having a structural unit of MADM (2-methyl-2-adamantyl methacrylate) / GBLM (α-methacryloyloxy-γ-butyrolactone) = 25 / 75 (molar ratio) (Mn = 3770)

[0356] (iv) XBisN-1: 13-(biphenyl-4-yl)-13H-dibenzoxanthene-3,10-diol (synthesized according to WO2013 / 024778)

[0357] <Acid Generator>

[0358] (i) WPAG-336 (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)

[0359] (ii) WPAG-145 (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)

[0360] As shown in Tables 3 and 4, the resin was added to a resin concentration of (i) 30 wt%, (ii) 35 wt%, (iii) 15 wt%, (iv) 25 wt%, and the acid generator (i) and (ii) were added to a concentration of 1 wt%, respectively, to prepare the resist auxiliary film compositions of Examples A1-1 to A2-3 and Comparative Examples A1-1 to 2-1. The state after stirring at room temperature for 24 hours was evaluated by visual inspection according to the following criteria.

[0361] Rating S: Dissolved (visual inspection confirmed clear solution)

[0362] Rating A: Basically dissolved (visual inspection confirmed a basically clear solution)

[0363] Rating C: Insoluble (visual inspection confirmed turbid solution)

[0364] [Table 3]

[0365]

[0366] [Table 4]

[0367]

[0368] As can be seen from Table 3, the resist auxiliary film compositions prepared in Examples A1-1 to A1-3 have better solubility in the resin and the acid generator than the resist auxiliary film composition of Comparative Example A1-1, and various resist auxiliary film compositions can be prepared.

[0369] As shown in Table 4, the resist auxiliary film compositions prepared in Examples A2-1 to A2-3 have better solubility in the resin and the acid generator than the resist auxiliary film composition of Comparative Example A2-1, and various resist auxiliary film compositions can be prepared.

[0370] [Examples 1d, 2d, Comparative Example 1d]

[0371] (Preparation of lower layer film composition)

[0372] The lower layer film composition was prepared according to the composition shown in Table 5. The following polymers, acid generators, crosslinking agents and organic solvents were used.

[0373] Polymer: The resin of formula (R1-1) is prepared as follows. That is, 30 g of 4,4-biphenol, 15 g of 4-biphenylcarboxaldehyde, 100 mL of butyl acetate, and 3.9 g of p-toluenesulfonic acid are added to prepare a reaction solution. The reaction solution is stirred at 90°C for 3 hours to react. Then, the reaction solution is concentrated and added dropwise to 400 mL of n-heptane. The resulting resin obtained in this way is solidified and purified, the generated white powder is filtered, and dried overnight at 40°C under reduced pressure to obtain a resin represented by the following formula (R1-1).

[0374]

[0375] Acid generator: Di-tert-butyldiphenyl iodide manufactured by Midori Kagaku Co., Ltd. Nonaflate(DTDPI)

[0376] Cross-linking agent: TMOM-BP manufactured by Honshu Chemical Industry Co., Ltd. (compound represented by the following formula)

[0377]

[0378] Organic solvent: 2-acetoxyisobutyric acid methyl ester (ABM)

[0379] Isopropyl 2-acetoxyisobutyrate (iPAIB)

[0380] [Table 5]

[0381]

[0382] Next, the lower film composition prepared in Examples 1d and 2d was coated on a SiO2 substrate with a film thickness of 300 nm, and baked at 240°C for 60 seconds and then at 400°C for 120 seconds to form an underlayer film with a film thickness of 85 nm. On the underlayer film, an ArF resist solution was coated and baked at 130°C for 60 seconds to form a photoresist layer with a film thickness of 140 nm.

[0383] Here, as the ArF resist solution, a solution prepared by blending 5 parts by mass of a resin represented by the following formula (1d), 1 part by mass of triphenylsulfonium nonafluoromethanesulfonate, 2 parts by mass of tributylamine, and 92 parts by mass of PGMEA was used.

[0384] The resin of the following formula (1d) is prepared as follows. That is, 4.15 g of 2-methyl-2-methacryloyloxyadamantane, 3.00 g of methacryloyloxy-γ-butyrolactone, 2.08 g of 3-hydroxy-1-adamantyl methacrylate, and 0.38 g of azobisisobutyronitrile are dissolved in 80 mL of tetrahydrofuran to form a reaction solution. The reaction solution is polymerized for 22 hours under a nitrogen environment with the reaction temperature maintained at 63°C, and then the reaction solution is added dropwise to 400 mL of n-hexane. The resulting resin obtained in this way is solidified and purified, the generated white powder is filtered, and dried overnight at 40°C under reduced pressure to obtain a resin represented by the following formula (1d).

[0385]

[0386] (In formula (1d), 40, 40, and 20 represent the ratio of each structural unit and do not indicate that it is a block copolymer.)

[0387] Next, the photoresist layer was exposed using an electron beam lithography apparatus (ELIONIX Co., Ltd., ELS-7500, 50 keV), baked (PEB) at 115° C. for 90 seconds, and developed using a 2.38 mass % tetramethylammonium hydroxide (TMAH) aqueous solution for 60 seconds to obtain a positive resist pattern.

[0388] [Comparative Example 1d]

[0389] A photoresist layer was directly formed on the SiO2 substrate in the same manner as in Examples 1d and 2d, except that the resist underlayer film was not formed, thereby obtaining a positive resist pattern.

[0390] [evaluate]

[0391] The shapes of the resist patterns of 40 nmL / s (1:1) and 80 nmL / S (1:1) obtained by observing the resist patterns of Examples 1d, 2d and Comparative Example 1d were observed using an electron microscope "S-4800" manufactured by Hitachi, Ltd., respectively. In the shape of the resist pattern after development, the one with no pattern collapse and good rectangularity was evaluated as "good", and otherwise it was evaluated as "bad". In addition, as a result of such observation, the minimum line width with no pattern collapse and good rectangularity was set as clarity as an evaluation index. And the minimum electron beam energy that can draw a good pattern shape was set as sensitivity as an evaluation index. The results are shown in Table 6.

[0392] [Table 6]

[0393]

[0394] As shown in Table 6, the resist patterns in Examples 1d and 2d are significantly better than those in Comparative Example 1d in terms of clarity and sensitivity. It can be considered that such a result is due to the effect of the resist auxiliary film composition on improving the adhesion of the resist pattern. In addition, it was confirmed that the resist pattern shape of Example 1d after development did not have pattern collapse and had good rectangularity. Moreover, based on the difference in the shape of the resist pattern after development, it is shown that the resist auxiliary film composition in Examples 1d and 2d has good adhesion to the resist material.

[0395] When the resist auxiliary film composition satisfying the requirements of this embodiment is used, a good resist pattern shape can be achieved compared to Comparative Example 1d which does not satisfy the requirements. Substances other than the resist auxiliary film composition described in the examples also exhibit the same effects as long as the requirements of this embodiment are satisfied.

[0396] [Examples 3d, 4d]

[0397] The resist auxiliary film composition prepared in Examples 1d and 2d is coated on a SiO2 substrate with a film thickness of 300nm, and baked at 240°C for 60 seconds and then at 400°C for 120 seconds to form a resist lower layer film with a film thickness of 90nm. A silicon-containing intermediate layer material is coated on the resist lower layer film, and baked at 200°C for 60 seconds to form a resist intermediate layer film with a film thickness of 35nm. The above-mentioned ArF resist solution is then coated on the resist intermediate layer film, and baked at 130°C for 60 seconds to form a photoresist layer with a film thickness of 150nm. Among them, as the silicon-containing intermediate layer material, a silicon atom-containing polymer (polymer 1) described in <Synthesis Example 1> of Japanese Patent Publication No. 2007-226170 is used.

[0398] The photoresist layer was then exposed to a mask using an electron beam lithography apparatus (ELIONIX Co., Ltd., ELS-7500, 50 keV), baked (PEB) at 115° C. for 90 seconds, and developed using a 2.38 mass % tetramethylammonium hydroxide (TMAH) aqueous solution for 60 seconds to obtain a 45 nm L / S (1:1) positive resist pattern.

[0399] Then, using "RIE-10NR" manufactured by Samco International, the silicon-containing resist intermediate film was dry-etched using the obtained resist pattern as a mask. Next, the resist lower film was dry-etched using the obtained silicon-containing resist intermediate film pattern as a mask, and the SiO2 film was dry-etched using the obtained resist lower film pattern as a mask.

[0400] Each etching condition is as follows.

[0401] Etching conditions of resist pattern to resist interlayer film

[0402] Power: 50W

[0403] Pressure: 20Pa

[0404] Time: 1min

[0405] Etching gas

[0406] Ar gas flow rate: CF4 gas flow rate: O2 gas flow rate = 50: 8: 2 (sccm)

[0407] Etching conditions of resist intermediate layer film pattern to resist lower layer film

[0408] Power: 50W

[0409] Pressure: 20Pa

[0410] Time: 2 minutes

[0411] Etching gas

[0412] Ar gas flow rate: CF4 gas flow rate: O2 gas flow rate = 50: 5: 5 (sccm)

[0413] Etching conditions of resist underlayer film pattern to SiO2 film

[0414] Power: 50W

[0415] Pressure: 20Pa

[0416] Time: 2 minutes

[0417] Etching gas

[0418] Ar gas flow rate: C5F 12 Gas flow rate: C2F6 gas flow rate: O2 gas flow rate = 50: 4: 3: 1 (sccm)

[0419] <Evaluation of pattern shape>

[0420] The pattern cross-sections (shape of the SiO2 film after etching) of Examples 3d and 4d obtained as described above were observed using an electron microscope "S-4800" manufactured by Hitachi, Ltd., and it was confirmed that in the examples using the anti-etching auxiliary film composition of this embodiment, the shape of the SiO2 film after etching during the multilayer anti-etching process was rectangular, without any defects, and the quality was good.

[0421] [Evaluation of embedding properties in step substrates]

[0422] The embedding property into the step substrate was evaluated according to the following procedure.

[0423] The resist auxiliary film composition prepared in Examples 1d and 2d was coated on a SiO2 substrate with a line and space of 60 nm and a film thickness of 150 nm, and baked at 400°C for 60 seconds to form a resist underlayer film with a film thickness of 100 nm. The cross section of the obtained resist underlayer film was cut out and observed using an electron beam microscope to evaluate the embedding property in the step substrate. The results are shown in Table 7.

[0424] <Evaluation Criteria>

[0425] A: There are no defects in the concave and convex parts of the SiO2 substrate with a line pitch of 60nm, and the resist lower layer film is buried.

[0426] C: There are defects in the concave and convex parts of the SiO2 substrate with a line pitch of 60nm, and the resist underlayer film is not buried.

[0427] [Evaluation of Flatness]

[0428] The above-obtained resist auxiliary film composition was applied to a SiO2 step substrate having a groove (aspect ratio: 1.5) with a width of 100nm, a spacing of 150nm, and a depth of 150nm and a groove (open area) with a width of 5μm and a depth of 150nm. Then, it was fired at 400°C for 120 seconds in an atmospheric environment to form a resist underlayer film with a film thickness of 100nm. The shape of the resist underlayer film was observed using a scanning electron microscope ("S-4800" manufactured by Hitachi High-Technologies Corporation), and the difference (ΔFT) between the maximum and minimum values ​​of the film thickness of the resist underlayer film on the groove and the open area was measured. The results are shown in Table 7.

[0429] <Evaluation Criteria>

[0430] S: ΔFT<10nm (optimal flatness)

[0431] A: 10nm≤ΔFT<20nm (good flatness)

[0432] B: 20nm≤ΔFT<40nm (flatness is acceptable)

[0433] C: 40nm≤ΔFT (poor flatness)

[0434] [Table 7]

[0435] Resist auxiliary film composition Step embedment Flatness Example 5d Composition of Example 1d A S Example 6d Composition of Example 2d A S

[0436] <Evaluation of step embedding properties and flatness>

[0437] It was confirmed that Examples 5d to 6d obtained as described above had good step embedding properties and flatness.

[0438] As long as the conditions of the present embodiment described above are satisfied, compositions other than the resist auxiliary film described in the examples can also exhibit the same effects.

Claims

1. A resist auxiliary film composition, characterized in that: A solvent B containing a resin A and a compound B1 represented by the following general formula (b-1), The resist auxiliary film composition has an active ingredient content of 45% by mass or less based on the total amount. In the formula (b-1), R 0 is an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an acyl group having 1 to 10 carbon atoms, R 1 It is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.

2. The resist auxiliary film composition according to claim 1, characterized in that: The solvent B does not contain 2-methoxyisobutyric acid methyl ester MBM, 2-formyloxyisobutyric acid methyl ester FBM and 2-acetoxyisobutyric acid methyl ester ABM.

3. The resist auxiliary film composition according to claim 1 or 2, characterized in that: It also contains at least one additive C selected from a photosensitizer and an acid generator.

4. The resist auxiliary film composition according to any one of claims 1 to 3, characterized in that R in the general formula (b-1) 0 is methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, cyclopropyl, cyclopentyl, cyclohexyl, phenyl, naphthyl, formyl, acetyl, propionyl or benzoyl.

5. The resist auxiliary film composition according to any one of claims 1 to 4, characterized in that R in the general formula (b-1) 1 It is a hydrogen atom, a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a sec-butyl group or a tert-butyl group.

6. The resist auxiliary film composition according to any one of claims 1 to 5, characterized in that The solvent B contains a compound represented by the following general formula (b-2) as a solvent B2 other than the compound B1, In the formula (b-2), R 1 It is a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.

7. The resist auxiliary film composition according to claim 6, characterized in that: The solvent B includes at least one selected from methyl 2-hydroxyisobutyrate and 2-hydroxyisobutyric acid as the solvent B2.

8. The resist auxiliary film composition according to claim 6 or 7, characterized in that: The content of the solvent B2 is less than 100 mass % based on 100 mass % of the total amount of the resist auxiliary film composition.

9. The resist auxiliary film composition according to any one of claims 1 to 8, characterized in that The resin A includes a novolac type resin A1.

10. The resist auxiliary film composition according to any one of claims 1 to 8, characterized in that The resin A includes an ethylenically unsaturated resin A2.

11. The resist auxiliary film composition according to any one of claims 1 to 8, characterized in that The resin A includes a high carbon type resin A3.

12. The resist auxiliary film composition according to any one of claims 1 to 8, characterized in that The resin A includes a silicon-containing resin A4.

13. The resist auxiliary film composition according to any one of claims 1 to 12, characterized in that The resist auxiliary film is a resist underlayer film.

14. The resist auxiliary film composition according to any one of claims 1 to 12, characterized in that The resist auxiliary film is a resist intermediate layer film.

15. The resist auxiliary film composition according to claim 6 or 7, characterized in that: The content of the solvent B2 is 100 mass % or less based on 100 mass % of the total amount of the compound B1.

16. A pattern forming method, characterized in that: include: A step A-1 of forming a resist underlayer film on a substrate using the resist auxiliary film composition according to claim 13; Step A-2 of forming at least one photoresist layer on the resist underlayer film; and After the step A-2, a step A-3 is performed in which a predetermined region of the photoresist layer is irradiated with radiation for development.

17. A pattern forming method, characterized in that: include: Step B-1 of forming a resist underlayer film on a substrate using the resist auxiliary film composition according to claim 13; Step B-2 of forming a resist intermediate layer film on the resist underlayer film; Step B-3 of forming at least one photoresist layer on the resist intermediate layer film; After the step B-3, a step B-4 of irradiating a predetermined region of the photoresist layer with radiation and developing the photoresist layer to form a resist pattern; and After the process B-4, the resist middle layer film is etched using the resist pattern as a mask, the resist lower layer film is etched using the obtained resist middle layer film pattern as an etching mask, and the substrate is etched using the obtained resist lower layer film pattern as an etching mask, thereby forming a pattern on the substrate in process B-5.

18. A pattern forming method, characterized in that: include: Step B-1 of forming a resist underlayer film on a substrate; Step B-2 of forming a resist intermediate layer film on the resist underlayer film using the resist auxiliary film composition according to claim 14; Step B-3 of forming at least one photoresist layer on the resist intermediate layer film; After the step B-3, a step B-4 of irradiating a predetermined region of the photoresist layer with radiation and developing the photoresist layer to form a resist pattern; and After the process B-4, the resist middle layer film is etched using the resist pattern as a mask, the resist lower layer film is etched using the obtained resist middle layer film pattern as an etching mask, and the substrate is etched using the obtained resist lower layer film pattern as an etching mask, thereby forming a pattern on the substrate in process B-5.

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