Photosensitive resin laminate, method for forming resist pattern, and method for manufacturing wiring board having conductor pattern

Abstract

Provided are: a photosensitive resin laminate enabling formation of a resist pattern excellent in fine line strength and resolution; a method for forming a resist pattern by using the photosensitive resin laminate; and a method for manufacturing a wiring board having a conductor pattern by using the photosensitive resin laminate. One embodiment of the present invention provides a photosensitive resin laminate having a support and a photosensitive resin layer. The photosensitive resin layer includes (A) an alkali-soluble polymer, (B) a photopolymerizable compound, and (C) a photopolymerization initiator, (A) the alkali-soluble polymer includes (a) a structural unit having a main chain portion constituting the main chain of (A) the alkali-soluble polymer, a carboxy group, and a linker group having two or more carbon atoms and linking the carboxy group to the main chain portion, and (b) a structural unit obtained from a (meth)acrylic acid, and the acid value of (A) the alkali-soluble polymer is 100-220 mg KOH / g.

Description

Photosensitive resin laminate, method for forming a resist pattern, and method for manufacturing a wiring board having a conductor pattern

[0001] The present invention relates to a photosensitive resin laminate, a method for forming a resist pattern, and a method for manufacturing a wiring board having a conductor pattern, etc.

[0002] In wiring boards and the like included in electronic devices, wiring patterns (hereinafter also referred to as "conductor patterns") are generally manufactured using a photolithography process. A photolithography process includes, for example, the steps of: forming a resist pattern by laminating a photosensitive resin layer in a photosensitive resin laminate onto a substrate and subjecting it to exposure and development; forming a conductor pattern by etching or plating the substrate on which the resist pattern has been formed; and removing the resist pattern from the substrate.

[0003] Patent Document 1 describes a transfer film having a temporary support and a photosensitive layer, wherein the photosensitive layer comprises polymer A and compound β, the polymer A has repeating units (a) having carboxyl groups linked to a main chain by a linking group having 1 or more carbon atoms, and the compound β has a structure b0 that reduces the amount of carboxyl groups in polymer A upon exposure.

[0004] Patent Document 2 describes an alkali-developable resist resin composition containing a copolymer (A) composed of repeating structural units represented by general formula (1) and repeating structural units having acid groups, and a polymerizable monomer (B), wherein in general formula (1), -COOX １ and -COOY １ (However, X １ represents a branched alkyl group or substituted branched alkyl group having 3 to 8 carbon atoms, or a cycloalkyl group or substituted cycloalkyl group having 4 to 8 carbon atoms, Y １ (This represents a branched alkyl group or substituted branched alkyl group having 3 to 8 carbon atoms, or a cycloalkyl group or substituted cycloalkyl group having 4 to 8 carbon atoms.)

[0005] International Publication No. 2022 / 196615, Japanese Patent Publication No. 2002-244293

[0006] The technology described in Patent Document 1 aims to provide a transfer film that can form a film with excellent low moisture permeability and scratch resistance, while the technology described in Patent Document 2 aims to obtain an alkali-developable resist resin composition that maintains sensitivity and resolution while exhibiting excellent heat resistance, print resistance and abrasion resistance, as well as excellent dielectric properties. However, in order to adapt the resist pattern to further finening of the conductor pattern, the resist pattern is required to be excellent not only in resolution but also in fine-line strength. Conventional technology has not yet provided a resist pattern that is excellent in both fine-line strength and resolution.

[0007] The present invention aims to solve the above problems and provide a photosensitive resin laminate capable of forming a resist pattern with excellent fine-line strength and resolution, a method for forming a resist pattern using the photosensitive resin laminate, and a method for manufacturing a wiring board having a conductor pattern using the photosensitive resin laminate.

[0008] The present invention encompasses the following items: [1] A photosensitive resin laminate having a support and a photosensitive resin layer, wherein the photosensitive resin layer comprises (A) an alkali-soluble polymer, (B) a photopolymerizable compound, and (C) a photopolymerization initiator, and the (A) alkali-soluble polymer comprises (a) a structural unit having a main chain portion constituting the main chain of the (A) alkali-soluble polymer, a carboxyl group, and a linking group having 2 or more carbon atoms that links the carboxyl group to the main chain portion, and (b) a structural unit derived from (meth)acrylic acid, and the acid value of the (A) alkali-soluble polymer is 100 mg KOH / g or more and 220 mg KOH / g or less, the photosensitive resin laminate. [2] The photosensitive resin laminate according to item 1, wherein the ratio of the (a) structural unit to 100% by mass of all structural units of the (A) alkali-soluble polymer is 20% by mass or less. [3] The photosensitive resin laminate according to item 1 or 2, wherein the linking group does not have a ring structure. [4] The photosensitive resin laminate according to any one of items 1 to 3, wherein the entire linking group is linear. [5] The photosensitive resin laminate according to any one of items 1 to 4, wherein the linking group contains one or more methylene groups. [6] The photosensitive resin laminate according to any one of items 1 to 5, wherein the ratio of the (b) constituent units to 100% by mass of the total constituent units of the (A) alkali-soluble polymer is 10% by mass to 35% by mass. [7] The photosensitive resin laminate according to any one of items 1 to 6, wherein the (A) alkali-soluble polymer further comprises (c) constituent units having an aromatic ring. [8] The photosensitive resin laminate according to any one of items 1 to 7, wherein the (A) alkali-soluble polymer further comprises (d) constituent units derived from (meth)acrylic acid ester. [9] The photosensitive resin laminate according to any one of items 1 to 8, wherein the (B) photopolymerizable compound comprises a compound having a bisphenol A skeleton.

[10] The photosensitive resin laminate according to any one of items 1 to 9, wherein the (C) photopolymerization initiator comprises a hexaarylbiimidazole compound.

[11] The photosensitive resin laminate according to any one of items 1 to 10 for manufacturing conductor patterns.

[12] A photosensitive resin laminate roll, which is a winding of the photosensitive resin laminate according to any one of items 1 to 11.

[13] A method for forming a resist pattern, comprising the steps of: laminating a photosensitive resin layer in a photosensitive resin laminate according to any one of items 1 to 11 onto a substrate; exposing the photosensitive resin layer; and developing the photosensitive resin layer after exposure to form a resist pattern.

[14] A method for manufacturing a wiring board having a conductive pattern, comprising the steps of: laminating a photosensitive resin layer in a photosensitive resin laminate according to any one of items 1 to 11 onto a substrate; exposing the photosensitive resin layer; developing the photosensitive resin layer after exposure to form a resist pattern; and etching or plating the substrate on which the resist pattern has been formed to form a conductor pattern on the substrate.

[0009] According to one aspect of the present invention, a photosensitive resin laminate capable of forming a resist pattern excellent in fine line strength and resolution, a method for forming a resist pattern using the photosensitive resin laminate, and a method for manufacturing a wiring board having a conductor pattern using the photosensitive resin laminate are provided.

[0010] Figure 1 is a plan view showing the configuration of the mask pattern for sensitivity evaluation. Figure 2 is a plan view showing the configuration of the mask pattern for adhesion evaluation. Figure 3 is a plan view showing the configuration of the mask pattern for resolution evaluation. Figure 4 is a plan view showing the configuration of the mask pattern for fine-line intensity evaluation.

[0011] The present invention will be described below. The present invention is not limited to this embodiment, and can be implemented with various modifications within the scope of its gist.

[0012] In this specification, if there are multiple structures represented by the same reference numeral in the same formula, unless otherwise specified, each structure may be selected independently and may be identical or different from one another. Similarly, if there are multiple structures represented by the same reference numeral in different formulas, unless otherwise specified, each structure may be selected independently and may be identical or different from one another. In this specification, various measurements are performed according to the methods described in the examples unless otherwise specified. In this specification, upper or lower limits in numerical ranges described in steps may be replaced by upper or lower limits in other numerical ranges described in steps, and further, by the corresponding values ​​described in the examples.

[0013] In this specification, “(meth)acrylic” means “acrylic” and / or “methacrylic,” “(meth)acrylate” means “acrylate” and / or “methacrylate,” and “(meth)acryloyl” means “acryloyl” and / or “methacryloyl.” A “(meth)acryloyl group compound” is, for example, referred to as a “(meth)acrylate compound.” In this specification, “process” is included in this term not only when it is an independent process, but also when it is not clearly distinguishable from other processes, as long as the function of the process is achieved. In the drawings, scale, shape and length may be exaggerated for further clarity. In this specification, “solids” of a photosensitive resin composition means the components of the photosensitive resin composition other than the solvent.

[0014] In one embodiment, unless otherwise specified: "developability" refers to the developability of the photosensitive resin layer (resist); "sensitivity" refers to the exposure sensitivity of the photosensitive resin layer (resist); "adhesion" refers to the adhesion performance between the resist pattern and the substrate; "resolution" refers to the resolution performance of the resist pattern; and "fine line strength" refers to the strength of the resist pattern.

[0015] <<Photosensitive Resin Laminate>> One aspect of the present invention provides a photosensitive resin laminate having a support and a photosensitive resin layer. The photosensitive resin layer of the present disclosure may be formed using the photosensitive resin composition of the present disclosure. In one embodiment, the photosensitive resin layer comprises (A) an alkali-soluble polymer (hereinafter also referred to as component (A)), (B) a photopolymerizable compound (hereinafter also referred to as component (B)), and (C) a photopolymerization initiator (hereinafter also referred to as component (C)), and may optionally contain additional components. In one embodiment, the alkali-soluble polymer (A) comprises (a) a structural unit (hereinafter also referred to as the (a) structural unit) having a main chain portion constituting the main chain of the alkali-soluble polymer (A), a carboxyl group, and a linking group having 2 or more carbon atoms that links the carboxyl group to the main chain portion, and (b) a structural unit derived from (meth)acrylic acid (hereinafter also referred to as the (b) structural unit). In one embodiment, (A) the acid value of the alkali-soluble polymer is 100 mg KOH / g or more. In another embodiment, (A) the acid value of the alkali-soluble polymer is 220 mg KOH / g or less.

[0016] (A) The carboxyl groups in the alkali-soluble polymer impart alkali developability to the photosensitive resin layer. In order to achieve a fine resist pattern after exposure, it is desirable to design the photosensitive resin layer so that the resist exhibits the desired rigidity and toughness. (A) The carboxyl groups in the alkali-soluble polymer can influence the rigidity and toughness of the resist through interactions between the carboxyl groups. The inventors have investigated various methods to improve the fine line strength in the resist pattern and have found that it is advantageous to have the (b) component unit as a component unit having a carboxyl group close to the main chain of the alkali-soluble polymer (A), and to have the (a) component unit as a component unit having a carboxyl group far from the main chain of the alkali-soluble polymer (A). Although not bound by theory, such linking groups and the carboxyl groups bonded thereto behave as highly mobile side chains and contribute to good interactions between carboxyl groups in the alkali-soluble polymer (A). Furthermore, the presence of such side chains makes it less likely for the swelling of the alkali-soluble polymer (A) to become excessive. The photosensitive resin layer (A) containing an alkali-soluble polymer in this embodiment is advantageous for improving the toughness of the resist and, therefore, the fine line strength of the resist pattern. According to one embodiment of the photosensitive resin laminate, for example, it is possible to form a resist pattern with good fine line strength even with a fine line width of 7 μm or less.

[0017] The following are examples of each element of the photosensitive resin laminate.

[0018] <Support> The support is a layer for supporting the photosensitive resin layer, such as a film, and a transparent substrate that can transmit exposure light (active light) is preferred. In a typical embodiment, the support is peeled off from the photosensitive resin layer before the exposure step in which the photosensitive resin layer is exposed, or before the development step in which the photosensitive resin layer is developed.

[0019] Suitable substrates for use as supports, particularly transparent substrates, include synthetic resins such as polyethylene, polypropylene, polycarbonate, and polyethylene terephthalate. Of these, polyethylene terephthalate (PET) is preferred as a support because it possesses a moderate balance of flexibility and strength.

[0020] From the viewpoint of ensuring good adhesion, the absorbance of the support at a wavelength of 365 nm is preferably 0.3 or less, more preferably 0.2 or less, even more preferably 0.1 or less, and most preferably 0.08 or less. The above absorbance may be 0 or greater.

[0021] It is preferable to use a film with few internal foreign matter, such as a high-quality film, as the support. Specifically, high-quality films include PET films synthesized using a Ti-based catalyst, PET films with small lubricant diameters and low lubricant content, PET films containing lubricant on only one side, thin-film PET films, PET films with smoothing treatment on at least one side, and PET films with roughening treatment such as plasma treatment on at least one side. By using a high-quality film as the support, the blocking of exposure light caused by internal foreign matter in the support can be reduced. In this case, exposure light is more easily irradiated onto the photosensitive resin layer, which tends to improve the resolution of the resist pattern.

[0022] The thinner the support material, the fewer internal foreign matter particles tend to be present, making it easier to prevent resolution degradation caused by the support material. On the other hand, if the thickness is insufficient, stretching deformation in the winding direction due to tension is more likely to occur during the support material manufacturing process, such as coating and winding, and tearing due to minute scratches is also more likely. If the strength of the support material is insufficient due to these factors, problems may arise such as wrinkles easily forming in the photosensitive resin laminate when it is laminated onto the substrate. From the above viewpoint, the thickness of the support material is preferably 5 μm to 25 μm, or 6 μm to 20 μm.

[0023] At least one side of the support may be subjected to a smoothing process using a calender or the like. This can reduce the surface roughness of one side of the support, particularly the surface roughness of the side in contact with the photosensitive resin layer, and potentially improve the resolution of the resist pattern.

[0024] The haze of the support is preferably 0.01% to 1.5%, more preferably 0.01% to 1.2%, and even more preferably 0.01% to 0.95%, from the viewpoint of improving the parallelism of the exposure light irradiated onto the photosensitive resin layer and obtaining high resolution.

[0025] <Photosensitive resin layer> The photosensitive resin layer may be formed using a photosensitive resin composition. The amount of each component in the photosensitive resin layer of the present disclosure may be the same as the amount of each component in the solid content of the photosensitive resin composition. From the viewpoint of being suitable for forming a resist pattern and a conductor pattern, the total content of component (A), component (B), and component (C) is, based on the total solid content of the photosensitive resin composition, preferably 90 mass% or more, or 95 mass% or more, and in one aspect, may be 100 mass%, or less than 100 mass%, or 98 mass% or less.

[0026] The thickness of the photosensitive resin layer is preferably 3 µm to 100 µm. From the viewpoint of the strength of the photosensitive resin layer, the thickness is preferably 3 µm or more, or 7 µm or more, or 10 µm or more, or 15 µm or more, or 25 µm or more, or 40 µm or more, and from the viewpoint of resolution, the thickness is preferably 100 µm or less, or 60 µm or less, or 50 µm or less. The thickness of the photosensitive resin layer may be selected according to the configuration and use of the photosensitive resin laminate, the configuration and use of a resist pattern obtained using the photosensitive resin laminate, the configuration and use of a conductor pattern or electronic device manufactured using the photosensitive resin laminate, and the like. When plating a substrate on which a resist pattern is formed, the thickness of the photosensitive resin layer is preferably 10 µm to 30 µm, more preferably 15 µm to 25 µm.

[0027] [Component (A): Alkali-soluble polymer] Component (A) is a polymer soluble in an alkaline aqueous solution. The component (A) of the present embodiment comprises (a) a main chain moiety constituting the main chain of the alkali-soluble polymer (A), a carboxy group, and a structural unit having a linking group with 2 or more carbon atoms that links the carboxy group to the main chain moiety, and (b) a structural unit derived from (meth)acrylic acid, and thus has a carboxy group in a side chain.

[0028] (A) The acid value of component (A) is, in one embodiment, 100 mg KOH / g or more, preferably 110 mg KOH / g or more, or 120 mg KOH / g or more, or 130 mg KOH / g or more, from the viewpoint of obtaining good resolution (positive resolution in one embodiment). The acid value is, in one embodiment, 220 mg KOH / g or less, preferably 210 mg KOH / g or less, from the viewpoint of obtaining good developability. In one embodiment, the acid value of the photosensitive resin layer or photosensitive resin composition of the present disclosure may be within the range exemplified above.

[0029] The acid value can be calculated by accurately weighing approximately 1 g of the sample, dissolving it in 100 mL of acetone, and then performing a neutralization titration with a 1 mol / L potassium hydroxide solution. The acid value (mgKOH / g) is then calculated based on the volume of potassium hydroxide solution added using the following formula: Acid value (mgKOH / g) = 56.1 × {Volume of 1 mol / L potassium hydroxide solution added (mL)} / {Mass of accurately weighed sample (g)}. The neutralization titration can be performed, for example, using a Hiranuma automatic titrator (COM-555) manufactured by Hiranuma Sangyo Co., Ltd.

[0030] (A) The weight-average molecular weight (Mw) of component (A) is preferably 10,000 or more, or 12,000 or more, or 15,000 or more, or 16,000 or more, or 17,000 or more, or 18,000 or more, or 19,000 or more, or 20,000 or more, or 21,000 or more, or 22,000 or more, or 23,000 or more, or 24,000 or more, from the viewpoint of obtaining good fine line strength. The Mw is preferably 60,000 or less, or 59,000 or less, or 58,000 or less, or 57,500 or less, or 57,000 or less, from the viewpoint of obtaining good developability.

[0031] (A) The degree of dispersion (Mw / Mn), which is the ratio of the weight-average molecular weight (Mw) to the number-average molecular weight (Mn) of component (A), may be 1.0 to 6.0 in one embodiment, from the viewpoint of obtaining good pattern formation.

[0032] (a) Constituent Units (a) Constituent units (a) have a main chain portion that constitutes the main chain of the alkali-soluble polymer (A), a carboxyl group, and a linking group having two or more carbon atoms that links the carboxyl group to the main chain portion. In one embodiment, the (a) constituent unit has a structural portion derived from an ethylenically unsaturated bond, and this structural portion may constitute a part of the main chain of the alkali-soluble polymer (A). The (a) constituent unit may be derived from a monomer having a carboxyl group and an ethylenically unsaturated bond (hereinafter also referred to as the (a) monomer). In one embodiment, the (a) monomer may be an unsaturated carboxylic acid or a derivative thereof. Examples of derivatives include maleimide, etc. In one embodiment, the (a) monomer may have one or more selected from a (meth)acryloyl group and a maleimide group. That is, the main chain portion may be a structure derived from one or more selected from a (meth)acryloyl group and a maleimide group.

[0033] The number of carbon atoms in the linking group is (a) two or more in one embodiment, preferably three or more, or four or more, from the viewpoint of obtaining the advantages of the presence of the constituent unit well. The number of carbon atoms is preferably 15 or less, or 13 or less, or 12 or less, from the viewpoint of alkali developability and (a) availability of monomers.

[0034] The linking group may be a group containing a hydrocarbon group which is aliphatic, aromatic, or a combination thereof. The linking group may also contain one or more heteroatoms selected from, for example, O, N, and S. In one embodiment, the linking group is a hydrocarbon group and an ester group -C(=O)O-, an imide group -N[-C(=O)-] ２The linking group may include one or more selected from amide groups -C(=O)NH- or -C(=O)NR- (wherein R is an organic group). An organic group means a group having one or more carbon atoms. In one embodiment, R may be a hydrocarbon group having 1 to 3 carbon atoms. Specific examples of linking groups include: hydrocarbon groups; and combinations of hydrocarbon groups with ester groups, imide groups, and / or amide groups. Aliphatic hydrocarbon groups may be linear, branched, cyclic, or a combination of two or more of these. Linear hydrocarbon groups are preferred in terms of good mobility of the carboxyl group. In a similar view, it is preferable that the linking group does not have a cyclic structure, and it is more preferable that the entire linking group is linear. In one embodiment, the number of carbon atoms in the hydrocarbon group is one or more, or two or more, or three or more, and in one embodiment, it is 12 or less, or 11 or less, or 10 or less. The hydrocarbon group may have substituents. Examples of substituents include one or more selected from hydroxyl groups (-OH), alkoxy groups (-OR), and mercapto groups (-SH). R is a hydrocarbon group. The carbon atoms of the substituent are also included in the carbon number of the hydrocarbon group or linking group.

[0035] In one preferred embodiment, the linking group comprises one or more methylene groups. The methylene groups can impart good mobility to the carboxyl groups of the constituent units. From the viewpoint of carboxyl group mobility, the portion adjacent to the methylene group in the linking group is preferably a carbonyl group, an ether group, an ester group, a cyclic hydrocarbon group, or a combination thereof.

[0036] (a) Examples of monomers include the following:

[0037] (a-1) 2-methacryloyloxyethyl succinic acid (number of carbon atoms in the linking group: 5)

[0038] (a-2) 6-maleimidohexanoic acid (number of carbon atoms in the linking group: 5)

[0039] (a-3) 2-Acryloyloxyethyl succinic acid (number of carbon atoms in the linking group: 6)

[0040] (a-4) 4-(N-maleimidomethyl)cyclohexane-1-carboxylic acid (number of carbon atoms in the linking group: 8)

[0041] (a-5) Mono-2-(methacryloyloxy)ethyl phthalate (number of carbon atoms in the linking group: 10)

[0042] (a-6) 2-Acryloyloxyethylhexahydrophthalic acid (number of carbon atoms in the linking group: 10)

[0043] (a-7) 3-maleimidopropionic acid (number of carbon atoms in the linking group: 2)

[0044] (a-8) 4-maleimidebutyric acid (number of carbon atoms in the linking group: 3)

[0045] In one embodiment of the linking group, the number of carbon atoms constituting the linking chain between the main chain and the carboxyl group (the minimum value if multiple carbon atoms are possible) may be within the range exemplified above for the number of carbon atoms in the linking group. For example, in (a-6) 2-acryloyloxyethylhexahydrophthalic acid, the number of carbon atoms constituting the linking chain between the main chain and the carboxyl group (the minimum value since multiple carbon atoms are possible) is 6 (see below). From the viewpoint of good mobility of the carboxyl group, the ratio of the number of carbon atoms constituting the linking chain between the main chain and the carboxyl group to the total number of carbon atoms in the linking group may be 0.5 or more, greater than 0.5, or 0.6 or more in one embodiment. For example, in (a-6), the above ratio is 6 / 10, or 0.6.

[0046] (a) The constituent units contribute to improving the toughness of the resist pattern and therefore the fine line strength, while tending to lower the glass transition temperature (Tg) of the photosensitive resin layer and therefore tending to make the resist pattern more flexible. If the resist pattern is excessively flexible, the adhesion between the resist pattern and the substrate may be reduced. From the above viewpoint, the ratio of the constituent units of (a) to 100% by mass of all constituent units of component (A) is preferably 20% by mass or less, or 15% by mass or less, or 10% by mass or less. From the viewpoint of obtaining the advantages of the presence of the constituent units of (a) well, the above ratio may be 1% by mass or more, or 2% by mass or more, in one embodiment.

[0047] (b) constituent units (b) are constituent units derived from (meth)acrylic acid. (b) constituent units contribute to the developability of the photosensitive resin layer. The ratio of (b) constituent units to 100% by mass of all constituent units of component (A) is preferably 10% by mass or more, or 15% by mass or more, from the viewpoint of obtaining the advantages of the presence of (b) constituent units, and preferably 35% by mass or less, or 32% by mass or less, or 30% by mass or less, from the viewpoint of fine wire strength.

[0048] The ratio of (b) component units to the total 100% by mass of (a) component units and (b) component units is preferably 50% by mass or more, or 60% by mass or more, or 70% by mass or more, from the viewpoint of developability, and preferably 97% by mass or less, or 95% by mass or less, or 90% by mass or less, from the viewpoint of fine wire strength.

[0049] The choice of methacrylic acid or acrylic acid as the monomer can be determined as desired. When acrylic acid is used, the photosensitive resin layer tends to be more flexible and the adhesion tends to be lower compared to when methacrylic acid is used. For example, methacrylic acid may be preferred when improving adhesion, while acrylic acid may be preferred when improving developability.

[0050] (c) constituent units. Component (A) may optionally have additional constituent units in addition to constituent units (a) and (b). In a preferred embodiment, component (A) may further include constituent units having an aromatic ring (hereinafter also referred to as (c) constituent units). However, among the constituent units having an aromatic ring, those included in constituent units (a) shall be treated as constituent units (a) and not as (c) constituent units. More specifically, the (c) constituent units are constituent units derived from monomers having an aromatic ring and an ethylenically unsaturated bond. The (c) constituent units may be constituent units that do not have a carboxyl group (more specifically, non-acidic constituent units).

[0051] (c) Examples of constituent units include those derived from styrene or styrene derivatives, phenylmaleimide, benzyl (meth)acrylate, etc. The styrene derivative may be a styrene derivative that does not have a carboxyl group, and examples include 4-methylstyrene, 4-hydroxystyrene, 4-methoxystyrene, 4-chlorostyrene, and 4-(chloromethyl)styrene. From the viewpoint of excellent adhesion, constituent units derived from styrene are preferred. The ratio of constituent units of (c) to 100% by mass of all constituent units of component (A), preferably the ratio of constituent units derived from styrene, is preferably 10% by mass or more, 20% by mass or more, or 30% by mass or more from the viewpoint of adhesion, and preferably 80% by mass or less, 70% by mass or less, or 65% by mass or less from the viewpoint of developability.

[0052] (d) Constituent Units In a preferred embodiment, component (A) may further contain constituent units derived from (d) (meth)acrylic acid ester (hereinafter also referred to as (d) constituent units). The (d) constituent units may be advantageous in maintaining good adhesion while effectively exhibiting the effect of improving the fine wire strength by using the (a) constituent units. The (meth)acrylic acid ester is a concept that includes linear alkyl esters, cyclic alkyl esters, and compounds in which hydrogen atoms in these ester compounds are substituted with hydroxyl groups, etc. Examples of (meth)acrylic acid esters include benzyl (meth)acrylate, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, lauryl (meth)acrylate, n-tetradecyl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, glycerin mono (meth)acrylate, isobolonyl (meth)acrylate, and dicyclopentanyl (meth)acrylate.

[0053] The ratio of component (d) to 100% by mass of all component (A) is, in one embodiment, 10% by mass or more, or 20% by mass or more, or 30% by mass or more, and in one embodiment, 85% by mass or less, or 80% by mass or less, or 75% by mass or less.

[0054] (Other constituent units) Component (A) may further contain constituent units other than those exemplified above. For example, constituent units derived from one or more compounds having ethylenically unsaturated bonds, such as vinyl alcohol, vinyl acetate, maleic anhydride, etc.

[0055] The content of component (A) may be 10% by mass or more, 20% by mass or more, 25% by mass or more, 30% by mass or more, 35% by mass or more, 40% by mass or more, 45% by mass or more, 50% by mass or more, 55% by mass or more, or 60% by mass or more, relative to the photosensitive resin layer or the total solid content of the photosensitive resin composition. Alternatively, the content may be 90% by mass or less, 80% by mass or less, 70% by mass or less, 60% by mass or less, or 50% by mass or less. A content of 90% by mass or less is preferable from the viewpoint of easy control of the development time, and a content of 10% by mass or more is preferable from the viewpoint of excellent edge fusion resistance. "Edge fusion resistance" refers to the amount of resist that spills out from the edge face when the photosensitive resin laminate roll is stored, and a smaller amount of spillage is preferable.

[0056] Component (A) can be synthesized by diluting the monomer, which is the compound described above, with a solvent such as acetone, methyl ethyl ketone, or isopropanol, mixing appropriate amounts of a radical polymerization initiator such as benzoyl peroxide and azoisobutyronitrile into the solution, and then heating and stirring. In some cases, component (A) can be synthesized by adding a portion of the mixture dropwise to the reaction solution. After the reaction is complete, the solvent may be further added to adjust the concentration to the desired level. In addition to solution polymerization, bulk polymerization, suspension polymerization, or emulsion polymerization may also be used as synthesis methods. Furthermore, synthesis may be carried out by living radical polymerization.

[0057] [Component (B): Photopolymerizable compound] Component (B) is a photopolymerizable compound, for example, a compound having one or more ethylenically unsaturated bonds in one molecule.

[0058] From the viewpoint of obtaining a photosensitive resin layer with appropriate flexibility, the photosensitive resin composition preferably contains a compound having two ethylenically unsaturated bonds per molecule. Furthermore, from the viewpoint of excellent crosslinking efficiency in the exposure process, the photosensitive resin composition may contain a compound having three, four, five, or six ethylenically unsaturated bonds per molecule.

[0059] From the viewpoint of excellent resolution, the content of the compound having two ethylenically unsaturated bonds in one molecule is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more, based on the total amount of component (B). The content may be 100% by mass or less than 100% by mass, based on the total amount of component (B).

[0060] If component (B) contains a compound having three or more ethylenically unsaturated bonds in one molecule, the content of the compound is preferably 30% by mass or less or 20% by mass or less, based on the total amount of component (B), from the viewpoint of improving crosslinking efficiency in the exposure process and thereby improving adhesion. The content may be 1% by mass or more or 5% by mass or more, based on the total amount of component (B).

[0061] Component (B) preferably contains a (meth)acrylate compound. With respect to component (B), the condition that "the (meth)acrylate compound has n (meth)acryloyl groups in one molecule" is sometimes referred to as "n-functional." For example, with respect to component (B), having one, two, three, four, five, or six ethylenically unsaturated bonds in one molecule may be referred to as "monofunctional (or monofunctional)," "difunctional," "trifunctional," "tetrafunctional," "pentafunctional," or "hexafunctional," respectively.

[0062] Examples of bifunctional (meth)acrylate compounds include alkyl di(meth)acrylate, 1,3-bis(meth)acryloyloxy-2-propanol, tricyclodecanol di(meth)acrylate, full orange (meth)acrylate, ethoxylated full orange (meth)acrylate, and propoxylated full orange (meth)acrylate.

[0063] Furthermore, examples of bifunctional (meth)acrylate compounds include polyalkylene glycol di(meth)acrylates and di(meth)acrylates having a bisphenol A structure. Here, "bisphenol A structure" is a concept that includes hydrogenated bisphenol A structure. Compounds having a bisphenol A skeleton are preferred from the viewpoint of adhesion.

[0064] Examples of the polyalkylene glycol di(meth)acrylate include polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, polytetramethylene glycol di(meth)acrylate, and the following general formula (I): (wherein R １ are each independently a hydrogen atom or a methyl group, and X １ O and Y １ O are each independently an oxyethylene group or an oxypropylene group, (X １ O)m1, (X １ O)m2, and (Y １ O)n1 are each independently a (poly)oxyethylene chain or a (poly)oxypropylene chain, m1 and m2 are each independently an integer of 0 to 40, provided that m1+m2 is 1 to 40, and n1 is 1 to 20).

[0065] As the polyalkylene glycol di(meth)acrylate represented by the above formula (I), R １ is a methyl group, m1+m2 = 6 (average value), n1 = 12 (average value), X １ O is an oxyethylene group, and Y １ O is an oxypropylene group, and examples thereof include a vinyl compound (for example, product name "FA-024M" manufactured by Resonac Corporation).

[0066] Examples of the di(meth)acrylate having a bisphenol A structure include the following general formula (II): (wherein R ２ are each independently a hydrogen atom or a methyl group, X ２ O and Y ２ O are each independently an oxyethylene group or an oxypropylene group, m3 and m4 are each independently an integer of 0 to 40, provided that m3+m4 is 1 to 40, and n2 and n3 are each independently an integer of 0 to 20, provided that n2+n3 is 0 to 20). In addition, the di(meth)acrylate having a hydrogenated bisphenol A structure is a compound obtained by adding hydrogen to the aromatic ring of the compound represented by the above formula (II).

[0067] The compound represented by the above formula (II) is BPE-200 (R ２ = Methyl group, X ２ O = oxyethylene group, m3 + m4 = 4, and n2 = n3 = 0), BPE-500 (R ２ = Methyl group, X ２ O = oxyethylene group, m3 + m4 = 10, and n2 = n3 = 0), BPE-900 (R ２ = Methyl group, X ２ O = oxyethylene group, m3 + m4 = 17, and n2 = n3 = 0) (Manufactured by Shin Nakamura Chemical Industry Co., Ltd., product name), FA-321M (R ２ = Methyl group, X ２ O = oxyethylene group, m3 + m4 = 10, and n2 = n3 = 0), and FA-P321M (R ２ = Methyl group, X ２ Examples include O = oxypropylene group, m3 + m4 = 10, and n2 = n3 = 0) (all manufactured by Resonaq, product name).

[0068] Component (B) preferably contains a compound represented by the above general formula (II) from the viewpoint of excellent adhesion and resolution. The content of the compound is preferably 1% by mass or more, more preferably 20% by mass or more, more preferably 50% by mass or more, and even more preferably 70% by mass or more, based on the total amount of component (B). The content may be 100% by mass or less than 100% by mass, based on the total amount of component (B).

[0069] In the compound represented by formula (II) above, the average value of n2 + n3 + m3 + m4 is preferably 20 or less, and more preferably 10 or less, from the viewpoint of excellent resolution and adhesion. Here, it is even more preferable that component (B) includes the compound in which the average value of n2 + n3 + m3 + m4 is greater than 5 and 10 or less, and the compound in which the average value of n2 + n3 + m3 + m4 is 5 or less. The average value of n2 + n3 + m3 + m4 may be 2 or more. Note that the number of constituent units of the oxyethylene group or oxypropylene group is an integer value in a single molecule and a rational number which is the average value in an aggregate of multiple molecules.

[0070] Commercially available bifunctional (meth)acrylate compounds include NK Ester® A-HD-N, A-NOD-N, A-DOD-N, A-NPG, 701A, A-200, A-400, A-600, A-1000, APG-200, APG-400, APG-700, A-PTMG65, A-DCP, ABE-300, A-BPE-4, A-BPE-10, A-BPE-20, HD-N, NOD-N, and the same. DOD-N, NPG, 701, 2G, 3G, 4G, 9G, 14G, 23G, 9PG, DCP, BPE-80N, BPE-100, BPE-200, BPE-500, BPE-900, BP E-1300N, NK Oligo (registered trademark) UA-4200, UA-160TM, UA-290TM, UA-W2A, UA-4400, UA-122P, U-200PA (manufactured by Shin-Nakamura Chemical Co., Ltd.), LightAction Relate® 3EG-A, 4EG-A, 9EG-A, 14EG-A, PTMGA-250, NP-A, MPD-A, 1.6HX-A, 1.9ND-A, DCP-A, BP-4EAL, BP-4PA, HPP-A, Light Ester G-201P (all manufactured by Kyoeisha Chemical Co., Ltd.), Funcryl® FA-124AS, FA-023M, FA-121M, FA-124M, FA-125M, FA-129 AS, FA-137M, FA-220M, FA-222A, FA-240A, FA-240M, FA-320M, FA-3218M, FA-321A, FA-321M, FA-324A, FA-731A, FA-P240A, FA-P270A, FA-PTG9A, FA-PTG9M, FA-PTG28A, FA-PTG49A (all manufactured by Resonaq), DPGDA, HDDA, TPGDA, EBECYL 145, EBECRYL 150, PEG400DA, EBECRYL 11, IRR 214-K, EBECRYL 130, EBECRYL PEG200DMA (all manufactured by Daicel Ornex), SR212, SR213, SR230, SR238F, SR259, SR268,SR272, SR306H, SR344, SR349, SR508, CD560, CD561, CD564, SR601, SR602, SR610, SR833S, SR9003, SR9045, SR9209, SR205, SR206, SR209, SR210, SR214, SR231, SR239, SR248, SR252, SR297, SR348, SR480, CD540, CD541, CD542, SR603, SR644, SR9036 (all manufactured by Arkema), KAYARAD (registered trademark) Examples include NPGDA, PEG400DA, FM-400, R-167, HX-220, HX-620, R-551, R-712, R-604, and R-684 (all manufactured by Nippon Kayaku Co., Ltd.).

[0071] Examples of trifunctional or more (meth)acrylate compounds include trimethylolpropane tri(meth)acrylate, glycerin tri(meth)acrylate, trisphenylmethane tri(meth)acrylate, trisphenylethane tri(meth)acrylate, isocyanuric acid tri(meth)acrylate, pentaerythritol (tri / tetra)(meth)acrylate, diglycerin tetra(meth)acrylate, triglycerin penta(meth)acrylate, tetraglycerin hexa(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, and dipentaerythritol (tetra / penta / hexa)(meth)acrylate.

[0072] Furthermore, examples of trifunctional or more (meth)acrylate compounds include compounds obtained by forming a (meth)acrylate from an alcohol having three or more groups in which alkylene oxide groups can be added to the molecule as a central skeleton, to which alkylene oxide groups such as ethylene oxide groups, propylene oxide groups, or butylene oxide groups are added, and (meth)acrylic acid. Examples of such compounds include trimethylolpropane alkylene oxide-modified tri(meth)acrylate, glycerin alkylene oxide-modified tri(meth)acrylate, trisphenylmethane alkylene oxide-modified tri(meth)acrylate, trisphenylethane alkylene oxide-modified tri(meth)acrylate, alkylene oxide-modified pentaerythritol (tri / tetra)(meth)acrylate, alkylene oxide-modified diglycerin tetra(meth)acrylate, alkylene oxide-modified triglycerin penta(meth)acrylate, alkylene oxide-modified tetraglycerin hexa(meth)acrylate, alkylene oxide-modified ditrimethylolpropane (tetra / penta / hexa)(meth)acrylate, alkylene oxide-modified dipentaerythritol (tetra / penta / hexa)(meth)acrylate, and alkylene oxide-modified isocyanuric acid tri(meth)acrylate. Preferred alkylene oxide groups include ethylene oxide groups, propylene oxide groups, and butylene oxide groups.

[0073] Trifunctional or more (meth)acrylate compounds may contain alkylene oxide-modified pentaerythritol (tri / tetra)(meth)acrylate and / or alkylene oxide-modified dipentaerythritol (tetra / penta / hexa)(meth)acrylate from the viewpoint of excellent developability.

[0074] Commercially available (meth)acrylate compounds with three or more functionalities include NK Ester® A-TMPT, A-TMPT-9EO, AT-20E, A-GLY-3E, A-GLY-9E, A-GLY-20E, A-9300, A-9200YN, A-TMM-3, A-TMM-3L, A-TMM-3LM-N, A-TMMT, ATM-35E, AD-TMP, A-DPH, and A-9550. A-DPH-12E, TPOA-50, NK Oligo® UA-7100, UA-1100H, U-6LPA, UA-33H, U-10HA, U-10PA, U-15HA (all manufactured by Shin Nakamura Chemical Industry Co., Ltd.), Light Acrylate® TMP-A, cPE-3A, PE-4A, DPE-6A (all manufactured by Kyoeisha Chemical Co., Ltd.), FA-731A (manufactured by Resonac Corporation), TMPTA, EBECRYL 160S, OTA 480, PETIA, PETRA, EBECRYL 40, PETA, EBECRYL 140, EBECRYL 1140, EBECRYL 1142, DPHA, EBECRYL 895, EBECRYL 896, EBECRYL TMPTMA (all manufactured by Daicel Ornex), SR351S, SR368, SR415, SR444, SR454, SR492, SR499, CD501, SR502, SR9020, D9021, SR9035, SR295, SR355, SR399, SR494, SR9041 (all manufactured by Arkema), KAYARAD (registered trademark) Examples include GPO-303, TMPTA, THE-330, TPA-330, PET-30, T-1420(T), RP-1040, DPHA, DPEA-12, D-310, and DPCA-20 (all manufactured by Nippon Kayaku Co., Ltd.).

[0075] The content of component (B) is preferably 30% by mass or more, and more preferably 35% by mass or more, relative to the total solid content of the photosensitive resin composition, from the viewpoint of excellent sensitivity, tackiness, and conformability. Furthermore, from the viewpoint of excellent edge fusion resistance, tackiness, and resolution, it is preferably 50% by mass or less, more preferably 45% by mass or less, and even more preferably 42% by mass or less. Note that "tackiness" refers to the adhesiveness of the photosensitive resin composition.

[0076] From the viewpoint of excellent edge fusion resistance, tackiness, and resolution, the ratio of the content of component (B) to the content of component (A) based on the total solid content of the photosensitive resin composition {value of (content of component (B) / content of component (A))} is preferably 1.2 or less, more preferably 1.1 or less, even more preferably 1.0 or less, and particularly preferably 0.9 or less. Furthermore, the ratio is preferably 0.5 or more, more preferably 0.55 or more, and particularly preferably 0.6 or more.

[0077] The number of ethylenically unsaturated double bonds per 100 g of solids in the photosensitive resin composition is preferably 0.1 to 0.3 moles. When the above number is 0.1 moles or more, it is easier to prevent contamination of the washing water by the elution of the photosensitive resin component from the cured resist pattern when washing with water after development. When the above number is 0.3 moles or less, it is easier to prevent contamination of the washing water because chipping and detachment of the cured resist pattern are less likely to occur when washing with water after development. The above number is preferably 0.1 moles or more, or 0.11 moles or more, or 0.12 moles or more, or 0.13 moles or more, and preferably 0.3 moles or less, or 0.28 moles or less, or 0.25 moles or less, or 0.22 moles or less, or 0.20 moles or less, or 0.18 moles or less, or 0.15 moles or less.

[0078] [Component (C): Photopolymerization initiator] Component (C) is a compound that generates radicals upon exposure to light (active light) to promote the radical polymerization of component (B). Examples of component (C) include hexaarylbiimidazole compounds, N-aryl-α-amino acid compounds, quinone compounds, aromatic ketone compounds, anthracene or anthracene derivatives, acetophenone compounds, acylphosphine oxide compounds, benzoin compounds, benzoin ether compounds, dialkylketal compounds, thioxanthone compounds, dialkylaminobenzoic acid ester compounds, oxime ester compounds, acridine compounds, pyrazoline derivatives, N-aryl amino acid ester compounds, and halogen compounds.

[0079] The content of component (C) is preferably 0.1 to 20% by mass, and more preferably 0.5 to 10% by mass, relative to the total solid content of the photosensitive resin composition. By adjusting the content of component (C) within the above range, sufficient sensitivity can be easily obtained, making it easier to transmit light sufficiently to the bottom of the photosensitive resin layer even with a small amount of exposure, and consequently, easier to achieve high resolution.

[0080] From the viewpoint of excellent sensitivity, resolution, and adhesion, it is preferable that the (C) component contains a hexaarylbiimidazole compound. In this case, from the same viewpoint, the content of the hexaarylbiimidazole compound in the photosensitive resin composition is preferably 0.1 to 15% by mass, and more preferably 0.5 to 10% by mass.

[0081] (C) It is preferable to use a combination of a hexaarylbiimidazole compound and a photopolymerization initiator other than a hexaarylbiimidazole compound (for example, an aromatic ketone compound) as component (C). In this case, the content of the photopolymerization initiator other than the hexaarylbiimidazole compound in the photosensitive resin composition is preferably 0.5% by mass or less, and more preferably 0.01 to 0.4% by mass. In this case, the content of the hexaarylbiimidazole compound in the photosensitive resin composition is preferably 0.1 to 10% by mass, and more preferably 0.5 to 5% by mass.

[0082] Examples of hexaarylbiimidazole compounds include dimers of compounds having a rophine structure (rophine dimers), namely, dimers of 2,4,5-triarylimidazole.Dimers of 2,4,5-triarylimidazole include the dimer of 2-(o-chlorophenyl)-4,5-diphenylimidazole (also known as 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole), 2,2'-bis-(2-fluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2'-bis-(2,3-difluoromethylphenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole, and 2 ,2'-bis-(2,4-difluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole,2,2'-bis-(2,5-difluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole,2,2'-bis-(2,6-difluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole,2,2'-bis-(2,3,4-trifluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)- biimidazole, 2,2'-bis-(2,3,5-trifluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2'-bis-(2,3,6-trifluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2'-bis-(2,4,5-trifluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2'-bis-(2,4,6-trifluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2'-bis-(2,4,6-trifluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl) Examples include trakis-(3-methoxyphenyl)-biimidazole, 2,2'-bis-(2,3,4,5-tetrafluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole, 2,2'-bis-(2,3,4,6-tetrafluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole, and 2,2'-bis-(2,3,4,5,6-pentafluorophenyl)-4,4',5,5'-tetrakis-(3-methoxyphenyl)-biimidazole.Among these, the dimer of 2-(o-chlorophenyl)-4,5-diphenylimidazole is preferred as the hexaarylbiimidazole compound from the viewpoint of excellent sensitivity, resolution, and adhesion.

[0083] Examples of N-aryl-α-amino acid compounds include N-phenylglycine, N-methyl-N-phenylglycine, and N-ethyl-N-phenylglycine. Among these, N-phenylglycine is preferred as the N-aryl-α-amino acid compound due to its excellent sensitizing effect.

[0084] Examples of quinone compounds include 2-ethylanthraquinone, octaethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthaquinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethylanthraquinone, and 3-chloro-2-methylanthraquinone.

[0085] Examples of aromatic ketone compounds include benzophenone, Michlaz ketone [4,4'-bis(dimethylamino)benzophenone], 4,4'-bis(diethylamino)benzophenone, and 4-methoxy-4'-dimethylaminobenzophenone.

[0086] Examples of anthracenes or anthracene derivatives include anthracene, 9,10-dialkoxyanthracene, 9,10-dimethoxyanthracene, 9,10-diethoxyanthracene, 9,10-dibutoxyanthracene, 9,10-diphenylanthracene, 2-ethylanthraquinone, octaethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, and 10-phenyl-9-anthraceneboronic acid. Among these, 9,10-dibutoxyanthracene, 9,10-diphenylanthracene, and 10-phenyl-9-anthraceneboronic acid are preferred as anthracenes or anthracene derivatives from the viewpoint of excellent sensitizing effect and adhesion, and 9,10-diphenylanthracene is particularly preferred.

[0087] Examples of acetophenone compounds include 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 1-(4-dodecylphenyl)-2-hydroxy-2-methylpropan-1-one, 4-(2-hydroxyethoxy)-phenyl(2-hydroxy-2-propyl)ketone, 1-hydroxycyclohexylphenyl ketone, and 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropanone-1, etc. Commercially available acetophenone compounds include the Irgacure® series (manufactured by BASF: Irgacure-907, Irgacure-369, and Irgacure-379, etc.).

[0088] Examples of acylphosphine oxide compounds include 2,4,6-trimethylbenzyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phosphine oxide, and bis(2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphine oxide. Commercially available acylphosphine oxide compounds include Lucilin TPO (manufactured by BASF) and Irgacure-819 (manufactured by BASF).

[0089] Examples of benzoin compounds and benzoin ether compounds include benzoin, benzoin ethyl ether, benzoin phenyl ether, methyl benzoin, and ethyl benzoin. Examples of dialkyl ketal compounds include benzyl dimethyl ketal and benzyl diethyl ketal. Examples of thioxanthone compounds include 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, and 2-chlorthioxanthone. Examples of dialkylaminobenzoic acid ester compounds include ethyl dimethylaminobenzoate, ethyl diethylaminobenzoate, ethyl-p-dimethylaminobenzoate, and 2-ethylhexyl-4-(dimethylamino)benzoate.

[0090] Examples of oxime ester compounds include 1-phenyl-1,2-propanedione-2-O-benzoyl oxime and 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl) oxime. Commercially available oxime ester compounds include CGI-325, Irgacure-OXE01, and Irgacure-OXE02 (all manufactured by BASF).

[0091] As acridine compounds, 1,7-bis(9,9'-acridinyl)heptane or 9-phenylacridine are preferred from the viewpoint of excellent sensitivity, resolution, and availability. As pyrazoline derivatives, 1-phenyl-3-(4-tert-butyl-styryl)-5-(4-tert-butyl-phenyl)-pyrazoline, 1-phenyl-3-(4-biphenyl)-5-(4-tert-butyl-phenyl)-pyrazoline, 1-phenyl-3-(4-biphenyl)-5-(4-tert-octyl-phenyl)-pyrazoline, and 1-phenyl-3-(4-methoxystyryl)-5-(4-methoxyphenyl)-pyrazoline are preferred from the viewpoint of excellent adhesion and ease of forming a highly rectangular resist pattern.

[0092] Examples of ester compounds of N-aryl amino acids include methyl ester of N-phenylglycine, ethyl ester of N-phenylglycine, n-propyl ester of N-phenylglycine, isopropyl ester of N-phenylglycine, 1-butyl ester of N-phenylglycine, 2-butyl ester of N-phenylglycine, tert-butyl ester of N-phenylglycine, pentyl ester of N-phenylglycine, hexyl ester of N-phenylglycine, pentyl ester of N-phenylglycine, and octyl ester of N-phenylglycine.

[0093] Examples of halogen compounds include amyl bromide, isoamyl bromide, isobutylene bromide, ethylene bromide, diphenylmethyl bromide, benzyl bromide, methylene bromide, tribromomethylphenylsulfone, carbon tetrabromide, tris(2,3-dibromopropyl)phosphate, trichloroacetamide, amyl iodide, isobutyl iodide, 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane, chlorinated triazine compounds, and diallylodonium compounds. Among these, tribromomethylphenylsulfone is preferred as the halogen compound.

[0094] [Additional Components] The photosensitive resin composition may optionally contain additional components. These additional components may be one or more of the following: dyes, antioxidants, stabilizers, sensitizers, plasticizers, etc.

[0095] (Dyes) Examples of dyes include leuco dyes and base dyes. Dyes are distinguished from pigments, which are poorly soluble or insoluble in water or organic solvents, by being soluble in water or organic solvents. Pigments are often included as colorants in photosensitive resin compositions for color filters, for example.

[0096] When a photosensitive resin composition contains a leuco dye, it tends to exhibit excellent color development in the unexposed areas of the photosensitive resin layer and superior peelability of the resist pattern. Examples of leuco dyes include leucocrystal violet (tris[4-(dimethylamino)phenyl]methane) and 3,3-bis(p-dimethylaminophenyl)-6-dimethylaminophthalide. Among these, leucocrystal violet is preferred as the leuco dye.

[0097] The leuco dye content is preferably 0.01 to 2% by mass, and more preferably 0.1 to 1.5% by mass, relative to the total solid content of the photosensitive resin composition. By adjusting the leuco dye content within this range, good color development and excellent sensitivity can be easily achieved.

[0098] Examples of base dyes include Diamond Green [CAS number (hereinafter the same): 633-03-4] (e.g., Aizen Diamond Green GH, manufactured by Hodogaya Chemical Co., Ltd.), Fuchsine [632-99-5], Methyl Violet [603-47-4], Methyl Green [82-94-0], Victoria Blue B [2580-56-5], Basic Blue 7 [2390-60-5] (e.g., Aizen Victoria Pure Blue BOH, manufactured by Hodogaya Chemical Co., Ltd.), Rhodamine B [81-88-9], Rhodamine 6G [989-38-8], and Basic Yellow 2 [2465-27-2]. Among these, Diamond Green is preferred as the base dye from the viewpoint of excellent colorability, hue stability, and exposure contrast.

[0099] The base dye content is preferably 0.001 to 3% by mass, more preferably 0.01 to 2% by mass, and even more preferably 0.04 to 1% by mass, relative to the total solid content of the photosensitive resin composition. From the viewpoint of obtaining good colorability, the base dye content is preferably above the lower limit, and from the viewpoint of improving the sensitivity of the photosensitive resin layer, it is preferably below the upper limit.

[0100] (Antioxidants) Examples of antioxidants include triphenyl phosphite (e.g., manufactured by ADEKA, trade name: TPP), tris(2,4-di-tert-butylphenyl) phosphite (e.g., manufactured by ADEKA, trade name: 2112), tris(mononylphenyl) phosphite (e.g., manufactured by ADEKA, trade name: 1178), and bis(mononylphenyl)-dinonylphenyl phosphite (e.g., manufactured by ADEKA, trade name: 329K). These can be used individually or in combination of two or more.

[0101] The antioxidant content in the photosensitive resin composition is preferably 0.01 to 0.8% by mass, and more preferably 0.01 to 0.3% by mass. From the viewpoint of exhibiting good color stability of the resist pattern and improving the sensitivity of the photosensitive resin layer, the antioxidant content is preferably above the lower limit. On the other hand, from the viewpoint of exhibiting good color stability while suppressing the color development of the resist pattern and improving adhesion, it is preferably below the upper limit.

[0102] Stabilizers can be used to improve the thermal stability and / or storage stability of the photosensitive resin composition. Examples of stabilizers include at least one of radical polymerization inhibitors and alkylene oxide compounds having a glycidyl group. These can be used individually or in combination of two or more.

[0103] Examples of radical polymerization inhibitors include p-methoxyphenol, hydroquinone, pyrogallol, naphthylamine, phenothiazine, tert-butylcatechol, cuprous chloride, 2,6-di-tert-butyl-p-cresol, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), triethylene glycol-bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate], nitrosophenylhydroxyamine aluminum salts (e.g., aluminum salts to which 3 moles of nitrosophenylhydroxylamine have been added), and diphenylnitrosamines. Among these, triethylene glycol-bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate], phenothiazine, tert-butylcatechol, and / or aluminum salts to which 3 moles of nitrosophenylhydroxylamine have been added are preferred. These can be used individually or in combination of two or more types.

[0104] Examples of alkylene oxide compounds having a glycidyl group include neopentyl glycol diglycidyl ether (e.g., Epolite 1500NP manufactured by Kyoeisha Chemical Co., Ltd.), nonaethylene glycol diglycidyl ether (e.g., Epolite 400E manufactured by Kyoeisha Chemical Co., Ltd.), bisphenol A-propylene oxide 2 molar adduct diglycidyl ether (e.g., Epolite 3002 manufactured by Kyoeisha Chemical Co., Ltd.), and 1,6-hexanediol diglycidyl ether (e.g., Epolite 1600 manufactured by Kyoeisha Chemical Co., Ltd.). These can be used individually or in combination of two or more.

[0105] The total content of the radical polymerization inhibitor and the alkylene oxide compound having a glycidyl group in the photosensitive resin composition is preferably 0.001 to 3% by mass, and more preferably 0.05 to 1% by mass. From the viewpoint of imparting good storage stability to the photosensitive resin composition, the total content is preferably above the lower limit, while from the viewpoint of maintaining the sensitivity of the photosensitive resin layer, it is preferably below the upper limit.

[0106] [Protective Film] The photosensitive resin laminate of this embodiment may further include a protective film. The support, the photosensitive resin layer, and the protective film may be laminated in this order. The protective film can be laminated on the photosensitive resin layer side of the laminate having the support and the photosensitive resin layer, and functions as a cover to protect the photosensitive resin layer.

[0107] When the adhesion force between the photosensitive resin layer and the support is significantly less than the adhesion force between the photosensitive resin layer and the protective film, the protective film can be easily peeled off the photosensitive resin layer. Examples of protective films include polyethylene film, polypropylene film, stretched polypropylene film, and polyester film. A release layer may be provided on the surface of the protective film.

[0108] The thickness of the protective film is preferably 10 to 100 μm, and more preferably 10 to 50 μm. Examples of protective films include Alphan® EM-501, E-200, E-201F, FG-201, MA-411 (all manufactured by Oji F-Tex Co., Ltd.), Trefan® KW37, 2578, 2548, 2500, YM17S, Therapiel® PJ271, PJ111, HP2, PJ101, WZ, MDA, MFA, TK07, BKE, BX8A, SY (all manufactured by Toray Industries, Inc.), GF-18, GF-818, GF-858 (all manufactured by Tamapoly Co., Ltd.), and others.

[0109] [Photosensitive resin laminate roll] A further embodiment of this invention provides a photosensitive resin laminate roll, which is a winding of the above-mentioned photosensitive resin laminate. The photosensitive resin laminate constituting the roll may be elongated in shape and may have a winding core at the center of the roll.

[0110] [Method for forming a resist pattern] A further embodiment of this embodiment provides a method for forming a resist pattern (manufacturing method) using the above-mentioned photosensitive resin laminate. Such manufacturing method includes the following steps: a step of laminating the photosensitive resin layer of the above-mentioned photosensitive resin laminate onto a substrate (lamination step); a step of exposing the photosensitive resin layer to light (exposure step); and a step of developing the photosensitive resin layer after exposure to form a resist pattern (development step).

[0111] (Lamination Process) In the lamination process, the photosensitive resin layer of the photosensitive resin laminate is laminated onto a substrate. Specifically, in the lamination process, if the photosensitive resin laminate includes a protective film, the protective film is peeled off from the photosensitive resin laminate to expose the photosensitive resin laminate, and then the photosensitive resin layer is heat-pressed onto the surface of the substrate using a laminator, laminating once or multiple times. Examples of substrate materials include copper, stainless steel (SUS), glass, and indium tin oxide (ITO). The heating temperature during lamination is generally 40 to 160°C. Heat pressing can be performed by using a laminator equipped with rolls, or by repeatedly passing the laminate of the substrate and photosensitive resin layer through the rolls several times. Heat pressing may be performed under reduced pressure if desired.

[0112] (Exposure Process) In the exposure process, the photosensitive resin layer is exposed. Specifically, in the exposure process, the photosensitive resin layer is exposed using an exposure machine. Exposure can be performed after peeling off the support if desired. When exposure is performed via a photomask in the exposure process, the amount of exposure may be determined by the illuminance of the light source and the exposure time, and may also be measured using a light meter.

[0113] In the exposure process, direct imaging exposure may be performed. In direct imaging exposure, the photosensitive resin layer is exposed by a direct writing device without using a photomask. As the light source at this time, for example, a semiconductor laser or an ultra-high pressure mercury lamp with a wavelength of 350 to 410 nm is used. If the writing pattern is controlled by a computer, the exposure amount may be determined by the illuminance of the exposure light source and the moving speed of the substrate.

[0114] In the exposure process, the method of irradiating with exposure light is preferably at least one method selected from projection exposure, proximity exposure, contact exposure, direct imaging exposure, and electron beam direct writing, with projection exposure or direct imaging exposure being more preferred.

[0115] After exposure and before the development process, the substrate and the photosensitive resin layer after exposure may be heated. The heating temperature is preferably 30 to 200°C, more preferably 30 to 150°C, and even more preferably 35 to 120°C. Heating can improve resolution and adhesion. Heating may be performed using an infrared or far-infrared heating furnace, hot air, a constant temperature bath, a hot plate, a hot air dryer, an infrared dryer, and a hot roll.

[0116] The elapsed time from exposure to heating, or more precisely, the time from when exposure is completed (i.e., when exposure is stopped) to when heating begins, is preferably 10 to 600 seconds, and more preferably 20 to 300 seconds. The time from when heating begins to when heating stops is preferably 1 to 120 seconds, and more preferably 5 to 60 seconds.

[0117] (Development Process) In the development process, the photosensitive resin layer after exposure is developed. Specifically, in the development process, the unexposed areas of the photosensitive resin layer after exposure are removed with a developing solution using a developing device. Subsequently, the unexposed or exposed areas are removed using a developing solution containing or consisting of an alkaline aqueous solution, thereby obtaining a resist pattern. If there is a support on the photosensitive resin layer after exposure, the support is peeled off from the photosensitive resin layer before the above development is performed.

[0118] As for alkaline aqueous solutions in developing solutions, Na ２ CO ３ _K ２ CO ３ Aqueous solutions of , and tetramethylammonium hydroxide are preferred. The alkaline aqueous solution is selected according to the properties of the photosensitive resin layer, for example, a concentration of 0.2 to 2% by mass of Na ２ CO ３An aqueous solution is used. The developer may contain a surfactant and / or an antifoaming agent, and may also contain a small amount of organic solvent to accelerate development. In the development process, it is preferable to keep the temperature of the developer constant within the range of 20 to 40°C.

[0119] After development, it is preferable to wash the substrate and resist pattern with water. Washing with water makes it easier to remove any remaining developer on the substrate and resist pattern. Examples of water for washing include pure water and industrial water. From the viewpoint of excellent resolution and ease of forming a highly rectangular resist pattern, a polyvalent metal salt at a concentration of 0.001 to 1% by mass may be mixed into the washing water, depending on the characteristics of the photosensitive resin layer. Examples of polyvalent metal salts include MgSO4. ４ These are some examples. It is preferable that the temperature of the washing water be kept constant within the range of 20 to 40°C.

[0120] After developing or any washing, the substrate and the formed resist pattern may be heated. The heating temperature is preferably 60 to 300°C. This heating makes it easier to improve the chemical resistance of the resist pattern. Heating may be carried out using an infrared or far-infrared heating furnace, or by hot air.

[0121] [Method for Manufacturing Conductor Patterns] The photosensitive resin laminate of this embodiment is particularly suitable for manufacturing conductor patterns because it can form a resist pattern with excellent fine-line strength and resolution. A further embodiment of this embodiment provides a method for manufacturing conductor patterns using the above-mentioned photosensitive resin laminate. This manufacturing method includes the following steps: a step of laminating the photosensitive resin layer of the above-mentioned photosensitive resin laminate onto a substrate; a step of exposing the photosensitive resin layer; a step of developing the photosensitive resin layer after exposure to form a resist pattern; and a step of etching or plating the substrate on which the resist pattern has been formed to form a conductor pattern on the substrate (conductor pattern formation step).

[0122] In the conductor pattern formation process, etching or plating is performed on the substrate on which the resist pattern has been formed. Specifically, in the conductor pattern formation process, a conductor pattern is formed on the surface (e.g., copper surface) of the substrate (as described above, for example, a metal plate and a metal film insulating plate) exposed by development, using a known etching method or plating method.

[0123] A method for manufacturing a conductor pattern may include a step (a peeling step) after the conductor pattern formation step in which the resist pattern remaining on the substrate is peeled off from the substrate. By removing the resist pattern from the substrate in the peeling step, a wiring board (for example, a printed wiring board) having the desired conductor pattern is obtained.

[0124] In the stripping process, an aqueous solution having a stronger alkalinity than the developer is used. Examples of the alkaline aqueous solution for stripping (hereinafter also referred to as "stripping solution") include an aqueous solution of NaOH or KOH with a concentration of 2 to 5% by mass, and an aqueous solution of an organic amine. The stripping solution may contain a small amount of water-soluble solvent. Examples of water-soluble solvents include alcohol. The temperature of the stripping solution in the stripping process is preferably in the range of 40 to 70°C.

[0125] In this embodiment, the photosensitive resin laminate can be used in the manufacture of printed circuit boards; lead frames for mounting IC chips; precision metal foil processing such as metal masks; packages such as ball grid arrays (BGAs) and chip-size packages (CSPs); tape substrates such as chip-on-film (COF) and tape automated bonding (TAB); semiconductor bumps; and partitions for flat panel displays such as ITO electrodes, address electrodes, and electromagnetic shielding.

[0126] By using the above-described method for manufacturing a conductor pattern, a further embodiment of this invention, a method for manufacturing a wiring board, is provided. Such a wiring board has a conductor pattern formed by the above-described conductor pattern forming step.

[0127] The embodiment will be further described below with reference to examples and comparative examples. However, this embodiment is not limited to the following examples.

[0128] <<Synthesis of Component (A)>> Compounds (a-1) to (a-8) shown in Table 1 and other compounds shown in Table 2 were mixed with azobisisobutyronitrile in the proportions (parts by mass) shown in Tables 2 and 3 to obtain solution (a). 140 g of methyl ethyl ketone and 40 g of ethanol were placed in a flask equipped with a stirrer, reflux condenser, thermometer, dropping funnel, and nitrogen gas inlet tube. The flask was then stirred while blowing nitrogen gas into it, and the temperature was raised to 80°C. Next, solution (a) was added to the flask dropwise over 4 hours at a constant dropping rate, and then the flask was stirred at 80°C for 2 hours.

[0129] Next, solution (b) was prepared by dissolving 0.5 parts by mass of azobisisobutyronitrile in 50 parts by mass of a mixture of 30 parts by mass of methyl ethyl ketone and 20 parts by mass of ethanol. 50.5 g of solution (b) was added to the flask dropwise over 10 minutes at a constant dropping rate, and then stirred at 80°C for 3 hours. Furthermore, the mixture in the flask was heated to 90°C over 30 minutes, and then kept warm and stirred at 90°C for 2 hours. After stirring was stopped, the mixture was cooled to room temperature (25°C). This yielded solutions of alkali-soluble polymers (A-1) to (A-26). The acid values ​​and weight-average molecular weights (Mw) of these solutions are shown in Tables 2 and 3.

[0130] The weight-average molecular weight was measured by gel permeation chromatography (GPC) and derived by conversion using a calibration curve for standard polystyrene. The GPC conditions were as follows: (GPC conditions) Instrument name: HLC-8420GPC manufactured by Tosoh Corporation Column: TSKgel SuperHZM-M manufactured by Tosoh Corporation (2 columns) Eluent: Tetrahydrofuran Measurement temperature: 40°C Flow rate: 0.35 mL / min Detector: RI detector

[0131] <Example 1> <Production of Photosensitive Resin Laminate> The components shown in Table 5 were mixed in the amounts (unit: parts by mass) (based on solid content) shown in Table 5. Methyl ethyl ketone was then added in an amount measured to achieve a solid content concentration of 60% by mass, and the mixture was thoroughly stirred to obtain a photosensitive resin composition solution. Note that the amounts (parts by mass) shown in Tables 5 to 7 are the mass of non-volatile components (solid content).

[0132] A 16 μm thick polyethylene terephthalate film (Toray Industries, Ltd., QS71) was prepared as a support film. The above-mentioned mixture was uniformly applied to the surface of the support film using a bar coater, and then dried in a 95°C dryer for 2 minutes and 30 seconds. This resulted in a photosensitive resin laminate having a 25 μm thick photosensitive resin layer on the support film.

[0133] Next, a 19 μm thick polyethylene film (Tamapoly Co., Ltd., GF-818) was laminated as a protective film to the surface of the photosensitive resin layer opposite to the support film. Here, the laminate of the support film, photosensitive resin layer, and protective film was treated as a photosensitive resin laminate.

[0134] The resulting photosensitive resin laminate was rolled using a conventional method to obtain a photosensitive resin laminate roll.

[0135] <Formation of resist pattern> [Surface preparation of substrate] The surface of a copper-clad laminate with a total thickness of 0.4 mm and an 18 μm thick rolled copper foil on its surface is prepared with 10% by mass H ２ SO ４ It was washed with an aqueous solution, and then washed again with pure water.

[0136] [Laminating Process] The washed copper-clad laminate was preheated to 50°C. The photosensitive resin layer was peeled off from the photosensitive resin laminate so that it was in contact with the surface of the preheated copper-clad laminate, and the laminate was laminated using a hot roll laminator (Asahi Kasei Corporation, AL-700) at a roll temperature of 105°C. This obtained an evaluation substrate. The air pressure during lamination was set to 0.35 MPa and the lamination speed was set to 1.5 m / min.

[0137] [Exposure Process] Two hours after lamination, the evaluation substrate was exposed to a projection exposure machine (UX-2003SM-AGG01, manufactured by Ushio Inc.) at a wavelength of 365 nm using a predetermined projection exposure mask pattern.

[0138] One minute after exposure, the evaluation substrate was heated for 30 seconds using a forced-air constant-temperature incubator (DKM600, manufactured by Yamato Scientific Co., Ltd.) set to 60°C.

[0139] [Developing Process] The support film was peeled off the photosensitive resin layer. Then, using an alkaline developer (Fujikiko Co., Ltd., dry film developer) at a spray pressure of 0.15 MPa, 1% by mass Na at 30°C was used. ２ CO ３ Developing was performed using an aqueous solution for a predetermined time (developing spray). Subsequently, the photosensitive resin layer was washed by spraying it with pure water for a predetermined time (washing spray). This formed a resist pattern on the evaluation substrate. The duration of the developing spray and washing spray was set to twice the minimum development time, as described later.

[0140] <<Examples 2 to 27, and Comparative Examples 1 to 5>> Except for the changes in components and formulation amounts shown in Tables 5 to 7, the photosensitive resin laminate was manufactured and the resist pattern was formed in the same manner as in Example 1.

[0141] ≪Evaluation≫ <Developability (Minimum Development Time: sec)> The above development process was performed on the evaluation substrate after the lamination process, and the shortest time required for the photosensitive resin layer to completely dissolve was measured visually, and this time was defined as the minimum development time. Using the measured minimum development time, the developability was evaluated based on the following criteria. The shorter the minimum development time, the better the developability. If the minimum development time was 24 seconds or less, the developability was considered good, and if the minimum development time was 21 seconds or less, the developability was considered particularly good.

[0142] <Sensitivity (Optimal exposure: mJ / cm) ２A mask pattern was prepared with a line width (L) / space width (S) (hereinafter abbreviated as "L / S") of 8 / 8 (unit: μm). Then, a pattern was formed on the evaluation substrate by performing the exposure and development processes described above using this mask pattern. The exposure amount (10 mJ / cm²) that resulted in the line width of the formed pattern being closest to 8 μm was then determined. ２ Interval) (Unit: mJ / cm) ２ The following was derived: A smaller exposure (optimal exposure) was considered to indicate higher sensitivity. The line width of the pattern was measured based on observation images obtained at 100x magnification using an optical microscope.

[0143] Figure 1 is a plan view showing the configuration of a mask pattern for sensitivity evaluation. In the figure, in region 100 of the photomask, the region that transmits exposure light is indicated by reference numeral 10 (transmitting region 10), and the region that does not transmit exposure light is indicated by reference numeral 1 (light-shielding region 1). In the figure, the light-shielding region 1 is indicated by a diagonal line. The transmitting region 10 has a predetermined width and extends in the x direction, and multiple such transmitting regions 10 are arranged in the width direction (y direction) at predetermined intervals. In this embodiment, since the unexposed portion of the photosensitive resin layer is removed after the development process described above, theoretically, based on the mask pattern in the figure, it is expected that a resist pattern with L / S corresponding to the width of the transmitting region 10 (L: line) and the width of the light-shielding region 1 (S: space) will be formed.

[0144] <Adhesion> The adhesion was evaluated using a photomask having a mask pattern with an L / S ratio of x / 3x {x = 1 to 20 (varying at 0.5 μm intervals)} (unit: μm). That is, the evaluation substrate obtained through the above surface preparation and lamination process was exposed to the photomask at the optimal exposure level. Subsequently, a resist pattern with a line length of 7 mm was formed by the above heating and development process.

[0145] Figure 2 is a plan view showing the configuration of a mask pattern for adhesion evaluation. In the figure, a transparent region 10 and a light-shielding region 1 are shown in region 100A of the photomask. In region 100A shown in the figure, the L / S value is different from that of region 100 shown in Figure 1.

[0146] The formed resist pattern was observed using an optical microscope at a magnification of 100x. In the observed image, lines (exposed areas) that were formed without meandering or missing lines were detected, and the adhesion was evaluated based on the following criteria using the minimum line width (L1). In this example, the smaller the minimum line width (L1), the better the adhesion. A minimum line width (L1) of 6.0 μm or less was considered acceptable, and a minimum line width (L1) of 5.0 μm or less was considered particularly good.

[0147] <Resolution> The evaluation was performed using a photomask having a mask pattern with an L / S ratio of x / x {x = 1 to 20 (varying at 0.5 μm intervals)} (unit: μm). That is, the evaluation substrate obtained through the above surface preparation and lamination process was exposed to the photomask at the optimal exposure level. Subsequently, a resist pattern with a line (exposed portion) length of 7 mm was formed by the above heating and development process.

[0148] Figure 3 is a plan view showing the configuration of a mask pattern for resolution evaluation. In the figure, a transparent region 10 and a light-shielding region 1 are shown in region 100B of the photomask. The light-shielding region 1 has a predetermined width and extends in the x-direction, and multiple such light-shielding regions 1 are arranged in the width direction (y-direction) at predetermined intervals. Based on the mask pattern in Figure 3, it is theoretically expected that a resist pattern with L / S corresponding to the width of the transparent region 10 (L: line) and the width of the light-shielding region 1 (S: space) will be formed, similar to the case based on the mask pattern in Figure 1.

[0149] The formed resist pattern was observed at 100x magnification using an optical microscope. In the observed image, lines (exposed areas) that did not meander or have gaps, and where spaces (unexposed areas) were formed without resist residue, were detected, and the resolution was evaluated using the minimum line width (L2) based on the following criteria. In this example, the smaller the minimum line width (L2), the better the resolution. A minimum line width (L2) of 5.5 μm or less was considered acceptable, and a minimum line width (L2) of 5.0 μm or less was considered particularly good.

[0150] <Fine Line Intensity> Evaluation was performed using a photomask with a mask pattern having an L / S of x / 200x {x = 1 to 20 (varying at 0.5 μm intervals)} (unit: μm). That is, the evaluation substrate obtained through the above surface preparation and lamination process was exposed to the photomask at the optimal exposure amount. Subsequently, a resist pattern with a line (exposed portion) length of 7 mm was formed by the above heating and development process.

[0151] Figure 4 is a plan view showing the configuration of a mask pattern for evaluating fine line intensity. In the figure, a transparent region 10 and a light-shielding region 1 are shown in region 100C of the photomask. In region 100C shown in the figure, the L / S value is different from that of region 100 shown in Figure 1.

[0152] The formed resist pattern was observed using an optical microscope at a magnification of 100x. In the observed image, lines (exposed areas) that were formed without meandering or missing lines were detected, and the fine line strength was evaluated using the minimum line width (L3) based on the following criteria. In this example, a smaller minimum line width (L3) was considered to indicate better fine line strength, a minimum line width (L3) of 7.0 μm or less was considered acceptable, and a minimum line width (L3) of 6.0 μm or less was considered particularly good.

[0153] The results of the above evaluation are shown in Tables 5 to 7. In all of the examples, it was confirmed that wiring boards with conductor patterns can be manufactured by conventional methods.

[0154]

[0155]

[0156]

[0157]

[0158]

[0159]

[0160]

[0161] The photosensitive resin laminate of this disclosure can be suitably applied, for example, to applications where the formation of fine conductive patterns is desired.

[0162] 1: Light-shielding area 10: Transmitting area 100, 100A, 100B, 100C: Areas in the photomask L: Line S: Space

Claims

1. A photosensitive resin laminate having a support and a photosensitive resin layer, wherein the photosensitive resin layer comprises (A) an alkali-soluble polymer, (B) a photopolymerizable compound, and (C) a photopolymerization initiator, the alkali-soluble polymer (A) comprises (a) a structural unit having a main chain portion constituting the main chain of the alkali-soluble polymer (A), a carboxyl group, and a linking group having 2 or more carbon atoms that links the carboxyl group to the main chain portion, and (b) a structural unit derived from (meth)acrylic acid, the acid value of the alkali-soluble polymer (A) is 100 mg KOH / g or more and 220 mg KOH / g or less.

2. The photosensitive resin laminate according to claim 1, wherein the ratio of the constituent units of (a) to 100% by mass of all constituent units of the alkali-soluble polymer of (A) is 20% by mass or less.

3. The photosensitive resin laminate according to claim 1 or 2, wherein the linking group does not have a ring structure.

4. The photosensitive resin laminate according to claim 1 or 2, wherein the entire linking group is linear.

5. The photosensitive resin laminate according to claim 1 or 2, wherein the linking group comprises one or more methylene groups.

6. The photosensitive resin laminate according to claim 1 or 2, wherein the ratio of the constituent units of (b) to 100% by mass of all constituent units of the alkali-soluble polymer (A) is 10% by mass to 35% by mass.

7. The photosensitive resin laminate according to claim 1 or 2, wherein the (A) alkali-soluble polymer further comprises (c) a structural unit having an aromatic ring.

8. The photosensitive resin laminate according to claim 1 or 2, wherein the (A) alkali-soluble polymer further comprises (d) a constituent unit derived from (meth)acrylic acid ester.

9. The photosensitive resin laminate according to claim 1 or 2, wherein the (B) photopolymerizable compound comprises a compound having a bisphenol A skeleton.

10. The photosensitive resin laminate according to claim 1 or 2, wherein the (C) photopolymerization initiator comprises a hexaarylbiimidazole compound.

11. A photosensitive resin laminate according to claim 1 or 2, for manufacturing a conductor pattern.

12. A photosensitive resin laminate roll, which is a winding body of the photosensitive resin laminate according to claim 1 or 2.

13. A method for forming a resist pattern, comprising the steps of: laminating a photosensitive resin layer in a photosensitive resin laminate according to claim 1 or 2 onto a substrate; exposing the photosensitive resin layer; and developing the photosensitive resin layer after exposure to form a resist pattern.

14. A method for manufacturing a wiring board having a conductive pattern, comprising the steps of: laminating a photosensitive resin layer in a photosensitive resin laminate according to claim 1 or 2 onto a substrate; exposing the photosensitive resin layer; developing the photosensitive resin layer after exposure to form a resist pattern; and etching or plating the substrate on which the resist pattern is formed to form a conductor pattern on the substrate.

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