Photosensitive element, photosensitive element roll, method for forming resist pattern, and method for forming conductor pattern

Abstract

The present disclosure is a photosensitive element roll formed by winding a photosensitive element having a photosensitive resin layer containing (A) a support film and (B) a photosensitive resin composition, wherein the average thickness of the support film (A) is 27 μm or more, the average thickness of the photosensitive resin layer (B) is 150 μm or more, and the photosensitive resin composition contains the following components:　(B1) an alkali-soluble polymer, (B2) a photopolymerizable compound, and (B3) a photopolymerization initiator.

Description

Photosensitive element, photosensitive element roll, method for forming resist pattern, and method for forming conductive pattern

[0001] The present disclosure relates to a photosensitive element, a photosensitive element roll, a method for forming a resist pattern, a method for forming a conductor pattern, and the like.

[0002] Conventionally, the manufacture of printed wiring boards and precision processing of metals are carried out using, for example, a photolithography process. In the photolithography process, for example, a photosensitive element is used. The photosensitive element generally has a support film, a photosensitive resin layer containing a photosensitive resin composition, and a protective film, in this order. Typically, a photosensitive element roll is obtained by winding the photosensitive element around a winding core.

[0003] A photosensitive element can be drawn out from the photosensitive element roll. The photosensitive resin layer in the photosensitive element is laminated on a substrate, and a resist pattern corresponding to the unexposed or exposed areas can be formed on the substrate by suitably removing a portion of the photosensitive resin layer from the substrate through an exposure step and a development step.

[0004] A substrate on which a resist pattern has been formed is subjected to plating treatment such as copper plating or solder plating, and the resist pattern is then peeled off from the substrate as necessary, thereby forming, for example, a conductor pattern (e.g., copper pillars, bumps, etc.) As a photosensitive element used for forming a conductor pattern, for example, the one described in Patent Document 1 has been proposed.

[0005] International Publication No. 2019 / 088268

[0006] In recent years, with the trend toward higher performance and higher density of semiconductor devices, there has been a demand for taller conductor patterns. In such cases, thick-film plating has tended to be used, and to achieve this, thick-film photosensitive resin layers have tended to be used. However, Patent Document 1 does not mention the above-mentioned tendency when photosensitive elements are rolled.

[0007] In a photosensitive element roll having a thick photosensitive resin layer, the photosensitive resin layer is easily affected during storage due to the thick photosensitive resin layer, and during use, a large amount of peeling residue tends to be left behind in the step of peeling the resist pattern. For this reason, for this type of photosensitive element roll, it is particularly desirable to have: storage stability during long-term storage; and peelability of the resist pattern from the substrate, which is in close contact with the substrate.

[0008] Therefore, an object of the present invention is to provide a photosensitive element roll that can improve storage stability during long-term storage and can improve peelability from a substrate, and a photosensitive element that can realize the photosensitive element roll. Another object of the present invention is to provide a method for forming a resist pattern and a method for forming a conductor pattern related to the photosensitive element and / or the photosensitive element roll.

[0009] One aspect of the present invention is as follows. [1] A photosensitive element roll formed by winding a photosensitive element having (A) a support film, and (B) a photosensitive resin layer containing a photosensitive resin composition, wherein the average thickness of the (A) support film is 27 μm or more, and the average thickness of the (B) photosensitive resin layer is 150 μm or more, and the photosensitive resin composition contains the following components: (B1) an alkali-soluble polymer, (B2) a photopolymerizable compound, and (B3) a photopolymerization initiator. [2] The photosensitive element roll according to item 1, wherein the average thickness of the (A) support film is 38 μm or more. [3] The photosensitive element roll according to item 1 or 2, wherein the difference between the maximum thickness and the minimum thickness of the (B) photosensitive resin layer is less than 5% of the average thickness of the (B) photosensitive resin layer. [4] A photosensitive element roll formed by winding a photosensitive element having (A) a support film, and (B) a photosensitive resin layer containing a photosensitive resin composition, wherein the (B) photosensitive resin layer has an average thickness of 150 μm or more, the difference between the maximum thickness and the minimum thickness of the (B) photosensitive resin layer is less than 5% of the average thickness of the (B) photosensitive resin layer, and the photosensitive resin composition contains the following components: (B1) an alkali-soluble polymer, (B2) a photopolymerizable compound, and (B3) a photopolymerization initiator. [5] The photosensitive element roll according to item 4, wherein the difference between the maximum thickness and the minimum thickness of the (B) photosensitive resin layer is less than 3% of the average thickness of the (B) photosensitive resin layer. [6] The photosensitive element roll according to item 4 or 5, wherein the difference between the maximum thickness and the minimum thickness of the (B) photosensitive resin layer is less than 1% of the average thickness of the (B) photosensitive resin layer. [7] The photosensitive element roll according to any one of items 1 to 6, wherein the (B) photosensitive resin layer has an average thickness of 250 μm or more. [8] The photosensitive element roll according to any one of items 1 to 7, wherein the (B) photosensitive resin layer has an average thickness of 300 μm or more. [9] The photosensitive element roll according to any one of items 1 to 8, wherein the (A) support film is a polyester film.

[10] The photosensitive element roll according to any one of items 1 to 9, wherein the (A) support film is a polyethylene terephthalate (PET) film having a haze of 2.0% or less.

[11] The photosensitive element roll according to any one of items 1 to 10, wherein the (A) support film is a polyethylene terephthalate (PET) film having a haze of 1.0% or less.

[12] The observation area of ​​the (A) support film is 10,000 mm. ２

[13] The photosensitive element roll according to any one of items 1 to 11, wherein the number of foreign particles having a maximum diameter of 10 μm or more contained within the observation area of ​​the support film (A) is 10,000 mm or less. ２The photosensitive element roll according to any one of items 1 to 12, wherein the number of foreign particles having a longest diameter of 10 μm or more contained within the component (B1) is 40 or less.

[14] The photosensitive element roll according to any one of items 1 to 13, wherein the mass ratio {(B1) / (B2)} of the component (B1) to the component (B2) is 1.1 to 2.0.

[15] The photosensitive element roll according to any one of items 1 to 14, wherein the component (B1) is a copolymer of: (B1-1) a compound having a carboxy group and an ethylenically unsaturated bond; and (B1-2) another compound having an ethylenically unsaturated bond.

[16] The photosensitive element roll according to any one of items 1 to 15, wherein the weight average molecular weight of the component (B1) is 20,000 to 70,000.

[17] The photosensitive element roll according to any one of items 1 to 16, wherein the component (B2) is a compound having a (meth)acryloyl group.

[18] The photosensitive element roll according to any one of items 1 to 17, wherein the component (B3) comprises an imidazole compound.

[19] The photosensitive element roll according to any one of items 1 to 18, wherein the photosensitive element further comprises a (C) protective film on the side of the (B) photosensitive resin layer opposite to the (A) support film, and the (C) protective film is selected from the group consisting of polyester films, polypropylene films, and polyethylene films.

[20] The photosensitive element roll according to item 19, wherein the (C) protective film is a polyethylene film.

[21] The photosensitive element roll according to any one of items 1 to 20, wherein the outer diameter of the end face in the longitudinal direction of the photosensitive element roll has a circularity of 5 to 500 μm.

[22] The photosensitive element roll according to any one of Items 1 to 21, wherein the photosensitive element roll is formed by winding the photosensitive element around a winding core, and the average thickness of the (A) support film relative to the outer diameter (μm) of the winding core {average thickness of (A) support film / outer diameter of winding core} is 0.000135 or more, and the average thickness of the (B) photosensitive resin layer relative to the outer diameter (μm) of the winding core {average thickness of (B) photosensitive resin layer / outer diameter of winding core} is 0.00075 or more.

[23] The photosensitive element roll according to any one of items 1 to 22, wherein the average thickness of the (A) support film is 100 μm or less, and / or the average thickness of the (B) photosensitive resin layer is 800 μm or less.

[24] A method for forming a resist pattern, comprising: a laminating step of laminating the (B) photosensitive resin layer of the photosensitive element roll according to any one of items 1 to 23 onto a substrate; an exposing step of exposing the (B) photosensitive resin layer; and a developing step of removing unexposed areas of the (B) photosensitive resin layer using an alkaline aqueous solution.

[25] A method for forming a conductor pattern, comprising: a step of obtaining a substrate with a resist pattern by the method according to item 24; a step of metal plating the resist pattern substrate to obtain a substrate with a conductor pattern; and a step of peeling the resist pattern from the substrate with a stripping solution.

[26] The method for forming a conductor pattern according to item 25, wherein the conductor pattern is a copper pillar or a bump.

[27] A photosensitive element having (A) a support film, and (B) a photosensitive resin layer containing a photosensitive resin composition, wherein the (A) support film has an average thickness of 27 μm or more, and the (B) photosensitive resin layer has an average thickness of 150 μm or more, and the photosensitive resin composition contains the following components: (B1) an alkali-soluble polymer, (B2) a photopolymerizable compound, and (B3) a photopolymerization initiator, and the (B1) component comprises: (B1-1) a compound having a carboxy group and an ethylenically unsaturated bond, and (B1-2) another compound having an ethylenically unsaturated bond,

[28] A photosensitive element having (A) a support film, and (B) a photosensitive resin layer containing a photosensitive resin composition, wherein the (B) photosensitive resin layer has an average thickness of 150 μm or more, a photosensitive element, wherein the difference between the maximum thickness and the minimum thickness of the (B) photosensitive resin layer is less than 5% of the average thickness of the (B) photosensitive resin layer, and the photosensitive resin composition contains the following components: (B1) an alkali-soluble polymer, (B2) a photopolymerizable compound, and (B3) a photopolymerization initiator, and the (B1) component is a copolymer of (B1-1) a compound having a carboxy group and an ethylenically unsaturated bond, and (B1-2) another compound having an ethylenically unsaturated bond.

[0010] According to the present invention, it is possible to provide a photosensitive element roll that can improve storage stability during long-term storage and can improve peelability from a substrate. Furthermore, according to the present invention, it is possible to provide a photosensitive element, a method for forming a resist pattern, and a method for forming a conductor pattern, which are related to the photosensitive element roll.

[0011] The present invention is not limited to the embodiments described below, and various modifications can be made within the scope of the present invention.

[0012] In the present specification, when a plurality of structures represented by the same symbol exist in the same formula, the structures may be independently selected and may be the same or different from each other, unless otherwise specified. When a plurality of structures represented by the same symbol exist in different formulas, the structures may be independently selected and may be the same or different from each other, unless otherwise specified. In the present specification, various measurements are carried out based on the methods described in the Examples unless otherwise specified.

[0013] In this specification, the upper or lower limit of a numerical range described in stages may be replaced by the upper or lower limit of a corresponding numerical range described in another stage, and may also be replaced by a corresponding value described in the Examples. The term "step" is included in this term not only when it is an independent step, but also when it is not clearly distinguishable from other steps, as long as the function of the step is achieved.

[0014] [First embodiment] [Photosensitive element] The photosensitive element of this embodiment has (A) a support film and (B) a photosensitive resin composition, and in one aspect, the (A) support film has an average thickness of 27 μm or more, the (B) photosensitive resin layer has an average thickness of 150 μm or more, and the photosensitive resin composition contains the following components: (B1) an alkali-soluble polymer, (B2) a photopolymerizable compound, and (B3) a photopolymerization initiator.

[0015] In one aspect of the photosensitive element of the present embodiment, the (B) photosensitive resin layer has an average thickness of 150 μm or more, the difference between the maximum thickness and the minimum thickness of the (B) photosensitive resin layer is less than 5% of the average thickness of the (B) photosensitive resin layer, and the photosensitive resin composition contains the following components: (B1) an alkali-soluble polymer, (B2) a photopolymerizable compound, and (B3) a photopolymerization initiator.

[0016] By using the photosensitive element of this embodiment, it is possible to suitably provide the photosensitive element roll of this embodiment, in particular a photosensitive element roll that can improve storage stability during long-term storage and can improve peelability from the substrate. Note that in the description of [Photosensitive Element Roll] described below, the description of the photosensitive element may be understood as the description of the photosensitive element of this embodiment. Furthermore, in the preferred aspects of [Photosensitive Element Roll] described below, the preferred aspects of the photosensitive element may be understood as the preferred aspects of the photosensitive element of this embodiment.

[0017] [Photosensitive Element Roll] This embodiment includes a photosensitive element roll formed by winding the photosensitive element of this embodiment. The photosensitive element roll of this embodiment is a photosensitive element roll formed by winding a photosensitive element having (A) a support film and (B) a photosensitive resin layer containing a photosensitive resin composition.

[0018] In one aspect of the photosensitive element roll of the present embodiment, the (A) support film has an average thickness of 27 μm or more, the (B) photosensitive resin layer has an average thickness of 150 μm or more, and the photosensitive resin composition contains the following components: (B1) an alkali-soluble polymer, (B2) a photopolymerizable compound, and (B3) a photopolymerization initiator.

[0019] In one aspect of the photosensitive element roll of the present embodiment, the (B) photosensitive resin layer has an average thickness of 150 μm or more, the difference between the maximum thickness and the minimum thickness of the (B) photosensitive resin layer is less than 5% of the average thickness of the (B) photosensitive resin layer, and the photosensitive resin composition contains the following components: (B1) an alkali-soluble polymer, (B2) a photopolymerizable compound, and (B3) a photopolymerization initiator.

[0020] With the trend toward higher performance and higher density of semiconductor devices, a tall conductor pattern is sometimes desired. In this case, thick-film plating tends to be used, and to achieve this, a thick photosensitive resin layer tends to be used. A photosensitive element roll having a thick photosensitive resin layer has a higher proportion of the photosensitive resin layer than a roll having a thin photosensitive resin layer, which makes the resin layer more susceptible to storage effects; The higher proportion of the photosensitive resin layer makes gauge bands (bumps on the roll surface) in the resin layer and / or winding slippage in the resin layer more likely to manifest as poor appearance; The resist pattern peels more from the substrate, which makes it more likely to leave residual peeling; Therefore, solving the above problems is particularly desirable. On the other hand, the photosensitive element roll of this embodiment can improve storage stability during long-term storage and can improve the releasability of the resist pattern.

[0021] Furthermore, the present inventors have focused on maintaining and / or improving the yield of conductive patterns formed by plating, given the increasing difficulty in forming conductive patterns (e.g., copper pillars, bumps, etc.). The photosensitive element roll of this embodiment can also improve the formability of conductive patterns.

[0022] The photosensitive element roll is obtained by rolling the photosensitive element. When rolling, the photosensitive element may be wound around a plastic core or a paper core. After the photosensitive element is wound around the core, the core may be pulled out in the width direction. The photosensitive element roll of this embodiment includes both a roll having a core and a roll not having a core.

[0023] The photosensitive element has an (A) support film and a (B) photosensitive resin layer, and may further have a (C) protective film on the side of the (B) photosensitive resin layer opposite the (A) support film. In one embodiment of the photosensitive element, the (A) support film and the (B) photosensitive resin layer are in contact, and when the (C) protective film is present, the (B) photosensitive resin layer and the (C) protective film are in contact. In the photosensitive element roll, by rolling the photosensitive element, the surface of the (A) support film opposite the photosensitive resin composition layer is in contact with the surface of the (C) protective film opposite the photosensitive resin composition layer. On the other hand, between the (A) support film and the (B) photosensitive resin layer, between the (B) photosensitive resin layer and the (C) protective film, and / or between the (A) support film and the (C) protective film, further other layers (for example, an intermediate layer and a release layer) may be provided.

[0024] <<(A) Support Film>> The support film is preferably transparent (transparent) and transmits light emitted from the exposure light source. Examples of the support film include polyester films, polyvinyl chloride films, vinyl chloride copolymer films, polyvinylidene chloride films, vinylidene chloride copolymer films, polystyrene films, polyacrylonitrile films, styrene copolymer films, polyamide films, and cellulose derivative films. Among these, polyester films are preferred. Examples of polyester films include PET films, polyvinyl alcohol films, and polymethyl methacrylate copolymer films, and among these, PET films are preferred. The support film may be stretched as necessary.

[0025] From the viewpoint of copper pillar formability, the haze of the support film is preferably 5.0% or less, more preferably 3.0% or less, even more preferably 2.0% or less, and particularly preferably 1.0% or less. As described above, the support film is preferably a PET film having a haze of 2.0% or less, and more preferably a PET film having a haze of 1.0% or less.

[0026] The average thickness of the support film is 27 μm or more, preferably 30 μm or more, and more preferably 38 μm or more, from the viewpoint of storage stability of the photosensitive element roll, and is preferably 100 μm or less from the viewpoints of slitting processability and economy.

[0027] The thickness of the support film is preferably as small as possible to prevent scattering of exposure light on the surface of the support film during exposure. In one embodiment, the difference between the maximum thickness and the minimum thickness of the support film is less than 5% of the average thickness of the support film. This difference is more preferably less than 3%, and particularly preferably less than 1%.

[0028] Here, the observation area of ​​the support film is 10,000 mm ２ The number of foreign particles with a maximum diameter of 10 μm or more contained within the support film is preferably small. Foreign particles are, for example, fine particles or voids. The voids may contain nuclei therein. ２ When a PET film having an area of ​​10 μm or more is observed with incident light, the number of foreign particles having a longest diameter of 10 μm or more is preferably 300 or less, more preferably 200 or less, even more preferably 100 or less, particularly preferably 50 or less or 40 or less, and most preferably 20 or less. This allows the exposure light to be irradiated onto the photosensitive resin layer without being blocked by the foreign particles, which makes it easy to improve the formability of copper pillars.

[0029] <<(B) Photosensitive Resin Layer>> The photosensitive resin layer, together with the support film, constitutes a photosensitive element. The average thickness of the photosensitive resin layer is 150 μm or more. This average thickness is preferably 200 μm or more, more preferably 250 μm or more, even more preferably 270 μm or more, even more preferably 300 μm or more, and particularly preferably 340 μm or more. In a plating method for forming copper pillars, a photosensitive element having a thick photosensitive resin layer (e.g., 150 μm or more) is suitable. A thick photosensitive resin layer makes it easy to maintain and / or improve the yield of copper pillars. The upper limit of the average thickness of the photosensitive resin layer may be, for example, 800 μm or less, 500 μm or less, or 400 μm or less.

[0030] From the viewpoint of storage stability during long-term storage of the photosensitive element roll, it is preferable that the thickness of the photosensitive resin layer has little variation. In one embodiment, the difference between the maximum thickness and the minimum thickness of the photosensitive resin layer is preferably less than 5% of the average thickness of the photosensitive resin layer. This difference is more preferably less than 3%, and particularly preferably less than 1%. This small difference makes it less likely that winding slippage and / or gauge bands will occur during long-term storage, and therefore, storage stability during long-term storage is likely to be improved.

[0031] <Photosensitive Resin Composition> The photosensitive resin layer contains a photosensitive resin composition. The photosensitive resin composition contains component (B1) an alkali-soluble polymer, component (B2) a photopolymerizable compound, and component (B3) a photopolymerization initiator. If desired, the photosensitive resin composition may contain, in addition to components (B1) to (B3), any component other than (B1) to (B3) (other components). Components (B1) to (B3) and other components may each be used alone, or two or more types may be used. Each component may also be used alone, or two or more types may be used as raw material components. The "solid content" of the photosensitive resin composition refers to the components of the photosensitive resin composition other than the solvent.

[0032] (Component (B1); Alkali-Soluble Polymer) The component (B1) is a polymer that is soluble in an alkaline aqueous solution. "Soluble in an alkaline aqueous solution" means, for example, that it is soluble in a developer, particularly the developer used in the examples. In one embodiment, the component (B1) is a copolymer of: (B1-1) a compound having a carboxy group and an ethylenically unsaturated bond; and (B1-2) another compound having an ethylenically unsaturated bond.

[0033] The content of the component (B1) in the photosensitive resin composition is preferably 20 to 90 mass %, more preferably 30 to 80 mass %, and even more preferably 40 to 70 mass %, based on the solid content of the photosensitive resin composition. When the photosensitive resin composition contains multiple components (B1), the total content of each component (B1) preferably falls within the above range.

[0034] The component (B1) exhibits alkali solubility by including the compound (B1-1) as a copolymerization component. The acid equivalent suitable for exhibiting alkali solubility is as described below. Examples of the compound (B1-1) include (meth)acrylic acid, fumaric acid, cinnamic acid, crotonic acid, itaconic acid, maleic anhydride, and maleic acid half ester (meth)acrylic acid. Of these, (meth)acrylic acid is preferred from the viewpoints of adhesion between the substrate and the resist pattern and resolution of the resist pattern. The compound (B1-1) may be used alone, or two or more types may be used.

[0035] Examples of the (B1-2) compound include aromatic (meth)acrylates such as alkyl (meth)acrylate and benzyl (meth)acrylate; (meth)acrylonitrile; (meth)acrylamide; and aromatic vinyl compounds such as styrene and styrene derivatives. Among these, it is preferable to contain styrene and / or benzyl (meth)acrylate, and it is particularly preferable to contain benzyl (meth)acrylate. The (B1-2) compound may be used alone or in combination of two or more.

[0036] The alkyl group of the alkyl (meth)acrylate may be linear, branched, or cyclic, and may have, for example, 1 or more, 2 or more, 3 or more, 4 or more, 5 or more, or 6 or more carbon atoms, and 12 or less, 11 or less, 10 or less, 9 or less, or 8 or less. Examples of the alkyl group of the alkyl (meth)acrylate include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, an ethylhexyl group, a nonyl group, a decyl group, an undecyl group, and a dodecyl group.

[0037] Styrene derivatives include, for example, oxystyrene, hydroxystyrene, acetoxystyrene, alkylstyrene, and halogenoalkylstyrene.

[0038] Preferred combinations of copolymerization components in component (B1) include, for example, (meth)acrylic acid and benzyl (meth)acrylate; (meth)acrylic acid, benzyl (meth)acrylate and an aromatic vinyl compound; and (meth)acrylic acid, benzyl (meth)acrylate and an alkyl (meth)acrylate. Specific examples include: methacrylic acid and benzyl methacrylate; acrylic acid, benzyl methacrylate and styrene; methacrylic acid, benzyl methacrylate and styrene; acrylic acid, benzyl methacrylate and butyl acrylate; methacrylic acid, benzyl methacrylate and butyl acrylate; acrylic acid, benzyl methacrylate and butyl acrylate; methacrylic acid, benzyl methacrylate and butyl acrylate; acrylic acid, benzyl methacrylate and 2-ethylhexyl acrylate; and methacrylic acid, benzyl methacrylate and 2-ethylhexyl acrylate. Furthermore, the component (B1) may contain a mixture of two or more of these copolymers.

[0039] The acid equivalent of component (B1) is preferably 250 or more, more preferably 370 or more, even more preferably 380 or more, even more preferably 390 or more, particularly preferably 400 or more, and most preferably 410 or more. The acid equivalent refers to the mass of component (B1) in grams per equivalent of carboxyl group. Having an acid equivalent of 250 or more may provide advantages such as a shorter minimum development time, improved resolution, improved processability with a stripping solution, and prevention of resist wrinkling during storage. The upper limit of the acid equivalent is preferably, for example, 600 or less. Having an acid equivalent of 600 or less makes it easier to improve both developability and strippability.

[0040] The weight-average molecular weight (Mw) of component (B1) is preferably 5,000 to 500,000, more preferably 5,000 to 300,000, even more preferably 10,000 to 200,000, still more preferably 20,000 to 70,000, and particularly preferably 30,000 to 70,000. A weight-average molecular weight (Mw) of 5,000 or more is likely to reduce development aggregates (aggregates in the photosensitive resin composition that may form during development), improve various properties of the unexposed film in the photosensitive element (edge ​​fusing property, cut-chip property, etc.), and improve the storage stability of the photosensitive element roll. On the other hand, a weight-average molecular weight (Mw) of 500,000 or less is likely to improve solubility in the developer, resolution, and copper pillar formability. The term "edge fuse property" refers to the property of suppressing edge fuse (a phenomenon in which a photosensitive resin layer protrudes from the edge of a roll when a photosensitive element is wound into a roll), and the term "cut chip property" refers to the property of suppressing cut chip (a phenomenon in which chips fly off when an unexposed film is cut with a cutter). If the cut chip property is poor, scattered chips may adhere to the photosensitive element, for example, and be transferred to a mask in a subsequent exposure step, which may result in defects.

[0041] When the component (B1) contains two or more types of alkali-soluble polymers, the weighted average value taking into account the mass ratio of each alkali-soluble polymer is treated as the weight average molecular weight (Mw) of the component (A).

[0042] (Component (B2): Photopolymerizable Compound) The component (B2) is a compound that polymerizes upon irradiation with light of a specific wavelength in the presence of a photopolymerization initiator. Examples of the component (B2) include a compound having an ethylenically unsaturated bond, and preferably a compound having a (meth)acryloyl group.

[0043] The double bond equivalent of component (B2) is preferably 150 or more or 160 or more, more preferably 170 or more, even more preferably 180 or more, still more preferably 190 or more, and particularly preferably 200 or more. When the double bond equivalent is 150 or more, resistance to plating penetration and stripper treatment ability tend to be improved. The double bond equivalent of the photopolymerizable compound may be, for example, 500 or less, 400 or less, or 300 or less. In this specification, "double bond equivalent" means the molecular weight per ethylenically unsaturated bond.

[0044] The proportion of the component (B2) is preferably 20 to 50 mass %, more preferably 20 to 40 mass %, based on the solid content of the photosensitive resin composition.

[0045] The compound of component (B2) may have 1 ethylenically unsaturated bond, and preferably has 2 or more ethylenically unsaturated bonds. Component (B2) preferably contains a compound having 3 or more or 4 or more ethylenically unsaturated bonds, and may contain a compound having 5, 6, or more ethylenically unsaturated bonds.

[0046] When component (B2) contains a compound having a (meth)acryloyl group (hereinafter referred to as a (meth)acrylate monomer) the number of functional groups in the (meth)acrylate monomer may be monofunctional, but is preferably difunctional or greater (e.g., trifunctional, tetrafunctional, pentafunctional, hexafunctional, or greater). In this specification, the term "number of functional groups" refers to the number of photopolymerizable functional groups per molecule of the compound, and in the case of a (meth)acrylate monomer, for example, is defined as the number of (meth)acryloyl groups per molecule.

[0047] When the compound having an ethylenically unsaturated bond contains a (meth)acrylate monomer having a large number of functional groups, the plating penetration resistance of the resist pattern tends to be improved. This effect is particularly remarkable when the acrylate monomer is a tri- or higher functional acrylate monomer.

[0048] Examples of the monofunctional component (B2) include: a compound in which (meth)acrylic acid is added to one end of a (poly)alkylene glycol; a compound in which (meth)acrylic acid is added to one end of a (poly)alkylene glycol and a group not having an ethylenically unsaturated bond (for example, an alkyl group) is added to the other end; etc. The alkylene group of the (poly)alkylene glycol preferably has 2 to 10 carbon atoms, more preferably 2 to 4 carbon atoms, and examples include a 1,2-ethylene group, a 1,2-propylene group, and a butylene group.

[0049] Examples of the bifunctional or higher functional component (B2) include compounds having two or more ethylenically unsaturated bonds and a skeleton such as (poly)alkylene glycol, bisphenol A, trimethylolpropane, glycerin, pentaerythritol, ditrimethylolpropane, or dipentaerythritol. Among these, compounds having a (meth)acrylate group are preferred, and compounds having an acrylate group are more preferred.

[0050] The bifunctional (B2) component having a (poly)alkylene glycol skeleton is represented by the following general formula (I): In the formula, each Y independently represents an alkylene group; １ , and R ２ each independently represents a methyl group or a hydrogen atom, and each n independently represents an integer of 1 to 50.

[0051] In the above formula (I), each Y is independently preferably an alkylene group having 2 to 10 carbon atoms, more preferably an alkylene group having 2 to 4 carbon atoms. Examples of alkylene groups include 1,2-ethylene, 1,2-propylene, and butylene. The (Y-O) moiety may contain repeating units of different alkylene oxides, or may consist of repeating units of the same alkylene oxide. When the (Y-O) moiety contains different alkylene oxides, the arrangement may be random, alternating, or block. n represents an integer of 1 to 50, preferably 3 to 20, and more preferably 6 to 10.

[0052] Examples of the compound represented by the general formula (I) above include: dimethacrylate of hexaethylene glycol, dimethacrylate of heptaethylene glycol, dimethacrylate of octaethylene glycol, dimethacrylate of nonaethylene glycol, dimethacrylate of decaethylene glycol, dimethacrylate of hexapropylene glycol, dimethacrylate of heptapropylene glycol, dimethacrylate of octapropylene glycol, dimethacrylate of nonapropylene glycol, and dimethacrylate of decapropylene glycol; dimethacrylate of a glycol having an average of 12 moles of propylene oxide added to both ends of polypropylene glycol, to which an average of 3 moles of ethylene oxide have been further added, and dimethacrylate of a glycol having an average of 18 moles of propylene oxide added to both ends of polypropylene glycol, to which an average of 15 moles of ethylene oxide have been further added.

[0053] The bifunctional component (B2) having a bisphenol A skeleton is represented by the following general formula (II): In the formula, each Y independently represents an alkylene group; １ , and R ２ each independently represents a methyl group or a hydrogen atom; n １ , and n ２ and each independently represent an integer of 1 to 100.} When the skeleton has an aromatic ring, the resistance to plating penetration tends to be improved.

[0054] In the above formula (II), each Y is independently preferably an alkylene group having 2 to 10 carbon atoms, more preferably an alkylene group having 2 to 4 carbon atoms. Examples of alkylene groups include a 1,2-ethylene group, a 1,2-propylene group, and a butylene group. From the viewpoints of imparting flexibility to the resist film, improving film strength, suppressing development aggregation, and / or increasing the reactivity of the ethylenically unsaturated bond, it is preferable that at least one or all of the Ys are 1,2-ethylene groups. The (Y-O) moiety may contain repeating units of different alkylene oxides, or may be composed of repeating units of the same alkylene oxide. When the (Y-O) moiety contains different alkylene oxides, the arrangement thereof may be random, alternating, or block. n １ , and n ２ each independently represents an integer of 1 to 100, preferably 1 to 50, more preferably 1 to 20, and even more preferably 1 to 10, and preferably 2≦n １ +n ２ ≦200, more preferably 2≦n １ +n ２ ≦100, more preferably 2≦n １ +n ２ ≦40, particularly preferably 2≦n １ +n ２ ≦20.

[0055] Examples of the compound represented by the general formula (II) above include: diacrylate of ethylene glycol having an average of 1 mole of ethylene oxide added to each end of bisphenol A, diacrylate of ethylene glycol having an average of 2 moles of ethylene oxide added to each end of bisphenol A, diacrylate of ethylene glycol having an average of 5 moles of ethylene oxide added to each end of bisphenol A, diacrylate of alkylene glycol having an average of 6 moles of ethylene oxide and an average of 2 moles of propylene oxide added to each end of bisphenol A, diacrylate of alkylene glycol having an average of 15 moles of ethylene oxide and an average of 2 moles of propylene oxide added to each end of bisphenol A, dimethacrylate of ethylene glycol having an average of 1 mole of ethylene oxide added to each end of bisphenol A, dimethacrylate of ethylene glycol having an average of 2 moles of ethylene oxide added to each end of bisphenol A, dimethacrylate of ethylene glycol having an average of 5 moles of ethylene oxide added to each end of bisphenol A, Examples include dimethacrylates of alkylene glycols in which an average of 6 moles of ethylene oxide and an average of 2 moles of propylene oxide have been added to both ends of bisphenol A, and dimethacrylates of alkylene glycols in which an average of 15 moles of ethylene oxide and an average of 2 moles of propylene oxide have been added to both ends of bisphenol A.

[0056] The trifunctional component (B2) having a trimethylolpropane skeleton includes a compound represented by the following general formula (III): {wherein n1, n2, and n3 each independently represent an integer of 1 to 25, provided that n1 + n2 + n3 is an integer of 3 to 75, and R1, R2, and R3 each independently represent a methyl group or a hydrogen atom.}

[0057] In the above formula (III), n1, n2, and n3 are each independently an integer of 1 to 25, preferably 1 to 10, and more preferably 1 to 3. n1 + n2 + n3 is an integer of 3 to 75, preferably 3 to 30, more preferably 3 to 15, and even more preferably 3 to 9. When n1 + n2 + n3 is 9 or greater, this is preferred from the viewpoints of suppressing the occurrence of a resist base, improving film strength, and / or imparting flexibility to the resist film. When n1 + n2 + n3 is 75 or less, this is preferred from the viewpoints of high resolution and adhesion, good release properties, and controlling edge fusing properties.

[0058] Examples of the compound represented by the general formula (III) include: a triacrylate in which an average of 3 moles of ethylene oxide in total has been added to the hydroxyl terminals of trimethylolpropane; a triacrylate in which an average of 9 moles of ethylene oxide in total has been added to the hydroxyl terminals of trimethylolpropane; a triacrylate in which an average of 15 moles of ethylene oxide in total has been added to the hydroxyl terminals of trimethylolpropane; and a triacrylate in which an average of 30 moles of ethylene oxide in total has been added to the hydroxyl terminals of trimethylolpropane.

[0059] The trifunctional component (B2) having a glycerin skeleton includes a compound represented by the following formula (VI): {wherein each Y independently represents an alkylene group, each R independently represents a methyl group or a hydrogen atom, and each n independently represents an integer of 0 to 200.}

[0060] In general formula (VI), each Y is independently preferably an alkylene group having 2 to 10 carbon atoms, more preferably an alkylene group having 2 to 4 carbon atoms. Examples of alkylene groups include 1,2-ethylene, 1,2-propylene, and butylene. From the viewpoints of imparting flexibility to the resist film, improving film strength, suppressing development aggregation, and / or increasing the reactivity of ethylenically unsaturated bonds, it is preferable that at least one or all of the Ys be a 1,2-ethylene group. The (Y-O) moiety may contain repeating units of different alkylene oxides, or may be composed of repeating units of the same alkylene oxide. When the (Y-O) moiety contains different alkylene oxides, the arrangement thereof may be random, alternating, or block. Each n is independently an integer from 0 to 200. It is preferable that at least one n is an integer from 1 to 200, and it is more preferable that three n's are integers from 1 to 200. In general formula (VI), n may be 0, i.e., no alkylene oxide moiety may be present. A total of n's of 1 or more is preferred from the viewpoints of suppressing the occurrence of resist skirts, improving film strength, and / or imparting flexibility to the resist film. A total of n's of 200 or less is preferred from the viewpoints of high resolution and adhesion, good release properties, and controlling edge fusing properties.

[0061] The tetrafunctional component (B2) having a pentaerythritol skeleton includes compounds represented by the following general formula (V): {wherein n1, n2, n3, and n4 each independently represent an integer of 1 to 25, n1 + n2 + n3 + n4 is an integer of 4 to 100, R1, R2, R3, and R4 each independently represent a methyl group or a hydrogen atom, R5, R6, R7, and R8 each independently represent an alkylene group, and when there are multiple R5, R6, R7, and R8, the multiple R5, R6, R7, and R8 may be the same as or different from one another.}

[0062] In the above formula (V), R5, R6, R7, and R8 are each independently preferably an alkylene group having 2 to 10 carbon atoms, more preferably an alkylene group having 2 to 4 carbon atoms. Examples of alkylene groups include 1,2-ethylene, 1,2-propylene, and butylene. From the viewpoints of imparting flexibility to the resist film, improving film strength, suppressing development aggregation, and / or increasing the reactivity of the ethylenically unsaturated bonds, it is preferable that at least one or all of R5, R6, R7, and R8 be a 1,2-ethylene group. n1 + n2 + n3 + n4 is 4 to 100, preferably 4 to 80, more preferably 4 to 40, even more preferably 4 to 20, and particularly preferably 4 to 16. It is preferable that n1 + n2 + n3 + n4 is 4 or greater from the viewpoints of suppressing the formation of a resist skirt, improving film strength, and / or imparting flexibility to the resist film. It is preferable that n1 + n2 + n3 + n4 is 100 or less from the viewpoints of high resolution and adhesion, good peeling properties, and controlling edge fusing properties.

[0063] Examples of the compound represented by the general formula (V) include: a tetraacrylate having an average of 4 moles of ethylene oxide added to the hydroxyl terminals of pentaerythritol, a tetraacrylate having an average of 9 moles of ethylene oxide added to the hydroxyl terminals of pentaerythritol, a tetraacrylate having an average of 12 moles of ethylene oxide added to the hydroxyl terminals of pentaerythritol, a tetraacrylate having an average of 15 moles of ethylene oxide added to the hydroxyl terminals of pentaerythritol, a tetraacrylate having an average of 20 moles of ethylene oxide added to the hydroxyl terminals of pentaerythritol, a tetraacrylate having an average of 28 moles of ethylene oxide added to the hydroxyl terminals of pentaerythritol, and a tetraacrylate having an average of 35 moles of ethylene oxide added to the hydroxyl terminals of pentaerythritol.

[0064] The hexafunctional (B2) component having a dipentaerythritol skeleton includes compounds represented by the following general formula (VI): {wherein each R independently represents a methyl group or a hydrogen atom, and each n independently represents an integer of 0 to 30.} In general formula (VI), n may be 0, that is, an ethylene oxide moiety may not be present.

[0065] In the above formula (VI), n's are each independently an integer of 0 to 30, preferably 1 to 20, more preferably 2 to 10, and even more preferably 3 to 5. The total of n's is 0 to 180, preferably 6 to 120, more preferably 12 to 60, and even more preferably 18 to 30. A total of n's of 1 or more is preferred from the viewpoints of suppressing the occurrence of a resist skirt, improving film strength, and / or imparting flexibility to the resist film. A total of n's of 180 or less is preferred from the viewpoints of high resolution and adhesion, good release properties, and controlling edge fusing properties.

[0066] Examples of the hexaacrylate compound represented by general formula (VI) include: dipentaerythritol hexaacrylate, a hexaacrylate having a total of 1 to 36 moles of ethylene oxide added to the six terminals of dipentaerythritol, a hexaacrylate having a total of 6 to 30 moles of ethylene oxide added to the six terminals of dipentaerythritol, a hexaacrylate having a total of 12 to 30 moles of ethylene oxide added to the six terminals of dipentaerythritol, and a hexaacrylate having a total of 18 to 30 moles of ethylene oxide added to the six terminals of dipentaerythritol.

[0067] In the photosensitive resin composition, the mass ratio of the component (B1) to the component (B2) {(B1) / (B2)} is preferably 1.0 or more and less than 2.5, more preferably 1.1 or more and less than 2.0, even more preferably 1.2 or more and less than 1.8, and still more preferably 1.3 or more and less than 1.7 (for example, 1.30 or more and less than 1.70). When this mass ratio is within the above range, the storage stability of the photosensitive element roll is likely to be improved, and the copper pillar formability and peelability are also likely to be improved.

[0068] (Component (B3): Photopolymerization Initiator) The component (B3) is a compound for initiating photopolymerization. The photopolymerization initiator can initiate polymerization of the component (B2) by irradiating it with light in the presence of the component (B2).

[0069] The content of component (B3) is preferably 0.01 to 20% by mass, more preferably 0.3 to 10% by mass, and even more preferably 1 to 5% by mass, based on the solid content of the photosensitive resin composition. When this content is 0.01% by mass or more, an exposure pattern with a sufficient residual film rate after development is likely to be obtained. When this content is 20% by mass or less, sufficient light is likely to be transmitted to the bottom surface of the resist, and therefore high resolution is likely to be obtained, and development aggregation in the developer can be suppressed.

[0070] Examples of the component (B3) include imidazole compounds, aromatic ketones, acridine compounds, N-aryl-α-amino acid compounds, and anthracene compounds.

[0071] Imidazole compounds are preferred from the viewpoint of improving the plating penetration resistance of the resist pattern and suppressing footing. Examples of the imidazole compound include imidazoles having an aliphatic group, such as methylimidazole, 2-ethyl-4-methylimidazole, 1-isobutyl-2-methylimidazole, 2-ethyl-4-methylimidazole, ethylimidazole, isopropylimidazole, 2,4-dimethylimidazole, undecylimidazole, and heptadecylimidazole; and imidazoles having an aromatic group, such as 1-benzyl-2-methylimidazole, phenylimidazole (e.g., 2-phenylimidazole), 2-phenyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, triarylimidazole, and dimers thereof. Among these, from the viewpoints of plating resistance and suppressing footing, imidazoles having an aromatic group are preferred, triarylimidazole (for example, lophine) or a dimer thereof is more preferred, and triarylimidazole dimer is even more preferred.

[0072] Examples of the triarylimidazole dimer include 2,4,5-triarylimidazole dimers such as 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(o-chlorophenyl)-4,5-di(methoxyphenyl)imidazole dimer, 2-(o-fluorophenyl)-4,5-diphenylimidazole dimer, 2-(o-methoxyphenyl)-4,5-diphenylimidazole dimer, and 2-(p-methoxyphenyl)-4,5-diphenylimidazole dimer.

[0073] Aromatic ketones are preferred from the viewpoint of improving sensitivity. Examples of aromatic ketones include benzophenone, N,N'-tetramethyl-4,4'-dimethylaminobenzophenone (Michler's ketone), N,N'-tetraethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone, 4,4'-bis(diethylamino)benzophenone, 2-benzyl-2-dimethylamino-1-(4-monophornophenyl)-butanone-1, and 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propanone-1. Of these, 4,4'-bis(diethylamino)benzophenone is preferred.

[0074] Acridine compounds are preferred from the viewpoints of improving sensitivity and achieving both high sensitivity and suppression of footing. Examples of acridine compounds include 1,7-bis(9,9'-acridinyl)heptane, 9-phenylacridine, 9-methylacridine, 9-ethylacridine, 9-chloroethylacridine, 9-methoxyacridine, 9-ethoxyacridine, 9-(4-methylphenyl)acridine, 9-(4-ethylphenyl)acridine, 9-(4-n-propylphenyl)acridine, 9-(4-n-butylphenyl)acridine, 9-(4-tert-butylphenyl)acridine, 9-(4-methoxyphenyl)acridine, 9-(4-ethoxyphenyl)acridine, and 9-(4-acetylphenyl)acridine. 9-(2-pyridyl)acridine, 9-(3-pyridyl)acridine, and 9-(4-pyridyl)acridine. Among these, 1,7-bis(9,9'-acridinyl)heptane and 9-phenylacridine are preferred in terms of sensitivity, resolution, availability, etc.

[0075] N-aryl-α-amino acid compounds are preferred from the viewpoint of improving sensitivity. Examples of N-aryl-α-amino acid compounds include N-phenylglycine, N-methyl-N-phenylglycine, and N-ethyl-N-phenylglycine.

[0076] Examples of 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, from the viewpoints of sensitization effect and adhesion, 9,10-dibutoxyanthracene, 9,10-diphenylanthracene, and 10-phenyl-9-anthraceneboronic acid are preferred, and 9,10-diphenylanthracene and 10-phenyl-9-anthraceneboronic acid are particularly preferred.

[0077] Further examples of the component (B3) include quinones such as 2-ethylanthraquinone, phenanthrenequinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthraquinone, 2-methyl-1,4-naphthoquinone, and 2,3-dimethylanthraquinone; benzoin ether compounds such as benzoin methyl ether, benzoin ethyl ether, and benzoin phenyl ether; benzil derivatives such as benzil methyl ketal; coumarin compounds; Pyrazoline derivatives such as 1-phenyl-3-(4-tert-butyl-styryl)-5-(4-tert-butyl-phenyl)-pyrazoline, 1-phenyl-3-(4-biphenyl)-5-(4-tert-butyl-phenyl)-pyrazoline, and 1-phenyl-3-(4-biphenyl)-5-(4-tert-octyl-phenyl)-pyrazoline; and the like.

[0078] (Other Components) The photosensitive resin composition may optionally contain, in addition to the above-described components (B1) to (B3), components other than (B1) to (B3) (other components). Examples of other components include dyes, halogen compounds, antioxidants, plasticizers, and solvents.

[0079] Dye The photosensitive resin composition may further contain a dye. The dye may include at least one selected from leuco dyes, fluoran dyes, and other coloring substances. When the photosensitive resin composition contains these components, the exposed portion develops color, improving visibility. Furthermore, the contrast between the exposed and unexposed portions increases, making it easier to recognize the alignment marker for exposure when an inspection machine reads it.

[0080] Examples of leuco dyes include tris(4-dimethylaminophenyl)methane [leuco crystal violet], bis(4-dimethylaminophenyl)phenylmethane [leucomalachite green], etc. Among these, leuco crystal violet is preferred from the viewpoint of obtaining good contrast.

[0081] Examples of fluoran dyes include 2-(dibenzylamino)fluoran, 2-anilino-3-methyl-6-diethylaminofluoran, 2-anilino-3-methyl-6-dibutylaminofluoran, 2-anilino-3-methyl-6-N-ethyl-N-isoamylaminofluoran, 2-anilino-3-methyl-6-N-methyl-N-cyclohexylaminofluoran, 2-anilino-3-chloro-6-diethylaminofluoran, 2-anilino-3-methyl-6-N-ethyl-N-isoamylaminofluoran, 2-anilino-3-methyl-6-N-methyl-N-cyclohexylaminofluoran, 2-anilino-3-chloro-6-diethylaminofluoran, Examples thereof include 2-anilino-3-methyl-6-N-ethyl-N-isobutylaminofluoran, 2-anilino-6-dibutylaminofluoran, 2-anilino-3-methyl-6-N-ethyl-N-tetrahydrofurfurylaminofluoran, 2-anilino-3-methyl-6-piperidinoaminofluoran, 2-(o-chloroanilino)-6-diethylaminofluoran, and 2-(3,4-dichloroanilino)-6-diethylaminofluoran.

[0082] The content of the leuco dye and the fluoran dye is preferably 0.1 to 10% by mass, more preferably 0.2 to 5% by mass, and even more preferably 0.3 to 1% by mass, based on the solid content of the photosensitive resin composition. When this content is 0.1% by mass or more, the contrast between exposed and unexposed areas tends to be improved. When this content is 10% by mass or less, the storage stability of the photosensitive resin layer is likely to be improved, and as a result, the generation of aggregates in the photosensitive resin layer during development tends to be suppressed.

[0083] Examples of other coloring substances include fuchsin, phthalocyanine green, auramine base, paramagienta, crystal violet, methyl orange, Nile blue 2B, malachite green (manufactured by Hodogaya Chemical Co., Ltd., Eizen (registered trademark) MALACHITE GREEN), basic blue 7 (e.g., Eizen (registered trademark) Victoria Pure Blue BOH conc., etc.), basic blue 20, and diamond green (manufactured by Hodogaya Chemical Co., Ltd., Eizen (registered trademark) DIAMOND GREEN GH).

[0084] The content of the other coloring substance is preferably 0.001 to 1% by mass based on the solid content of the photosensitive resin composition. When this content is 0.001% by mass or more, contrast tends to be improved, and when it is 1% by mass or less, storage stability tends to be improved.

[0085] Halogen Compound The photosensitive resin composition may further contain a halogen compound, or may contain a halogen compound together with the leuco dye. When the photosensitive resin composition contains a leuco dye and a halogen compound, adhesion and contrast tend to be improved.

[0086] 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, and chlorinated triazine compounds. Among these, tribromomethylphenylsulfone is preferred. Halogen compounds such as tribromomethylphenylsulfone are highly effective when used in combination with an acridine-based compound as component (B3), and in this case are preferred from the viewpoints of improving resolution, adhesion, sensitivity, contrast, tent film puncture resistance, suppressing resist footing, and / or etching resistance.

[0087] From the above viewpoints, the content of the halogen compound is preferably 0.01% by mass or more, based on the solid content of the photosensitive resin composition. This content is more preferably 0.1% by mass or more, even more preferably 0.3% by mass or more, and particularly preferably 0.5% by mass or more. Furthermore, it is preferable that this content be 3% by mass or less, from the viewpoints of maintaining the storage stability of the hue in the photosensitive resin layer and suppressing the generation of aggregates in the photosensitive resin layer during development. This content is more preferably 2% by mass or less, even more preferably 1.5% by mass or less.

[0088] Antioxidant The photosensitive resin composition may further contain an antioxidant. The antioxidant can improve the thermal stability and storage stability of the photosensitive resin layer. The antioxidant is preferably at least one of a radical polymerization inhibitor and a benzotriazole.

[0089] Examples of radical polymerization inhibitors include p-methoxyphenol, hydroquinone, pyrogallol, naphthylamine, tert-butylcatechol, biphenol, 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), 4,4'-thiobis(6-tert-butyl-m-cresol), Examples of such phenols include 4,4'-butylidenebis(3-methyl-6-tert-butylphenol), 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, styrenated phenol (for example, trade name "ANTAGE SP" manufactured by Kawaguchi Chemical Industry Co., Ltd.), tribenzylphenol (for example, trade name "TBP" manufactured by Kawaguchi Chemical Industry Co., Ltd., a phenol compound having 1 to 3 benzyl groups), diphenylnitrosamine, and phenothiazine.

[0090] Examples of benzotriazoles include 1,2,3-benzotriazole, 1-chloro-1,2,3-benzotriazole, bis(N-2-ethylhexyl)aminomethylene-1,2,3-benzotriazole, bis(N-2-ethylhexyl)aminomethylene-1,2,3-tolyltriazole, and bis(N-2-hydroxyethyl)aminomethylene-1,2,3-benzotriazole.

[0091] The benzotriazoles may have a carboxy group, and examples of benzotriazoles having a carboxy group (carboxybenzotriazoles) include 4-carboxy-1,2,3-benzotriazole, 5-carboxy-1,2,3-benzotriazole, N-(N,N-di-2-ethylhexyl)aminomethylenecarboxybenzotriazole, N-(N,N-di-2-hydroxyethyl)aminomethylenecarboxybenzotriazole, N-(N,N-di-2-ethylhexyl)aminoethylenecarboxybenzotriazole, and mixtures thereof. Among these, a mixture of 4-carboxy-1,2,3-benzotriazole and 5-carboxy-1,2,3-benzotriazole is preferred, and the mixing ratio by mass is preferably about 1:1.

[0092] The content of the antioxidant is preferably 0.01 to 3 mass %, more preferably 0.05 to 1 mass %, based on the solid content of the photosensitive resin composition. When this content is 0.01 mass % or more, the storage stability of the photosensitive resin layer is improved, and when it is 3 mass % or less, sensitivity is easily maintained and decolorization of the dye tends to be suppressed.

[0093] Plasticizer The photosensitive resin composition may further contain a plasticizer. Examples of the plasticizer include glycol esters such as polyethylene glycol, polypropylene glycol, polyoxypropylene polyoxyethylene ether, polyoxyethylene monomethyl ether, polyoxypropylene monomethyl ether, polyoxyethylene polyoxypropylene monomethyl ether, polyoxyethylene monoethyl ether, polyoxypropylene monoethyl ether, and polyoxyethylene polyoxypropylene monoethyl ether; phthalate esters of diethyl phthalate; o-toluenesulfonic acid amide, p-toluenesulfonic acid amide, tributyl citrate, triethyl citrate, triethyl acetylcitrate, tri-n-propyl acetylcitrate, and tri-n-butyl acetylcitrate; propylene glycol in which propylene oxide is added to both ends of bisphenol A, ethylene glycol in which ethylene oxide is added to both ends of bisphenol A, and aluminum salts in which 1 to 3 moles of nitrosophenylhydroxylamine are added. Among these, from the viewpoint of resistance to plating penetration, an aluminum salt having 3 moles of nitrosophenylhydroxylamine added thereto is preferred.

[0094] The content of the plasticizer is preferably 1 to 50% by mass, more preferably 1 to 30% by mass, based on the solid content of the photosensitive resin composition. When the amount of plasticizer is 1% by mass or more, delays in development time are easily suppressed and flexibility is easily imparted to the cured film. When this content is 50% by mass or less, insufficient curing and edge fuse tend to be suppressed.

[0095] Solvent The photosensitive resin composition layer is formed by applying a coating liquid in which the photosensitive resin composition is dispersed in a solvent to a support film or to any intermediate layer to be applied to the support film, and then drying. The resulting photosensitive resin layer may contain residual solvent. Examples of the solvent include ketones such as methyl ethyl ketone (MEK); alcohols such as methanol, ethanol, and isopropanol; and toluene. The content of the solvent remaining in the photosensitive resin layer is preferably 5% by mass or less, and more preferably 3% by mass or less, based on the solid content of the photosensitive resin composition.

[0096] <(C) Protective Layer (Protective Film)> The protective film serves to protect the photosensitive resin layer. When the photosensitive element includes a (C) protective film on the surface of the (B) photosensitive resin layer, the protective film preferably has an appropriate adhesive strength to the photosensitive resin layer. The adhesive strength of the protective film to the photosensitive resin layer is preferably sufficiently smaller than the adhesive strength of the support film to the photosensitive resin layer, so that the protective film can be easily peeled off from the photosensitive resin layer. Examples of protective films include polyethylene film, polypropylene film, and films with excellent peelability as disclosed in JP-A-59-202457, with polyethylene being the most preferred from the viewpoint of peelability. Furthermore, a larger difference in tensile modulus from the support film reduces the likelihood of slippage of the photosensitive element during winding, thereby improving storage stability. Therefore, a film having a tensile modulus of 2000 MPa or less, more preferably 1000 MPa or less, and even more preferably 100 MPa or less is preferred. For example, a polyethylene film is the most preferred protective film. The thickness of the protective layer is preferably 10 to 100 μm, more preferably 10 to 50 μm.

[0097] [Method for manufacturing photosensitive element roll] Another aspect of this embodiment is a method for manufacturing a photosensitive element roll. The method for manufacturing a photosensitive element roll may include a method for manufacturing a photosensitive element. The photosensitive element can be manufactured by laminating a support film, a photosensitive resin layer, and the like. The photosensitive element may further have a protective film laminated on the side of the photosensitive resin layer opposite the support film. The photosensitive element roll can be manufactured by winding the photosensitive element around a winding core such as a plastic winding core or a cardboard tube winding core.

[0098] Known methods can be used as the lamination method. For example, the components used in the photosensitive resin layer are mixed with a solvent that dissolves them to obtain a solution (coating liquid). The solvent ratio is preferably such that the viscosity of the coating liquid is 500 to 4,000 mPa·s at 25°C. The coating liquid is applied to a support film and then dried, thereby forming a photosensitive resin layer on the support film. Known methods can be used for coating, and examples include methods using a roll coater with various coater heads such as a slot die coater, lip coater, or comma coater.

[0099] The circularity of the outer diameter of the end face in the longitudinal direction of the photosensitive element roll is preferably 5 to 500 μm, which makes it easier to achieve the effects of this embodiment.

[0100] Furthermore, when the photosensitive element roll is wound around a core, it is preferable that the ratio of the average thickness of the (A) support film to the outer diameter (μm) of the core {average thickness of the (A) support film / outer diameter of the core} is 0.000135 or more, and the ratio of the average thickness of the (B) photosensitive resin layer to the outer diameter (μm) of the core {average thickness of the (B) photosensitive resin layer / outer diameter of the core} is 0.00075 or more. This makes it easier to achieve the effects of this embodiment.

[0101] Furthermore, it is preferable that the average thickness of the (A) support film is 100 μm or less and / or the average thickness of the (B) photosensitive resin layer is 800 μm or less. This makes it easier to achieve the effects of this embodiment.

[0102] <Method for measuring average thickness> The average thickness may be measured using a dot-type thickness meter such as the FT-A series contact continuous thickness meter manufactured by Fujiwork Co., Ltd. or the dot-type VL-50 series manufactured by Mitutoyo Corporation; or a non-contact in-line thickness meter such as the AccureX series manufactured by Hutec Corporation.

[0103] In the examples, the thickness (average thickness) of the photosensitive resin layer is measured using a non-contact in-line thickness meter, and the thickness value is calibrated to be the same as the value measured using a contact film thickness meter. Specifically, the thickness is measured at 1 mm intervals along the width direction of the photosensitive element within a range of 97% of the entire width direction centered on the center of the width direction to obtain thickness data, and the thickness (μm) of the photosensitive resin layer is derived by averaging the thicknesses in the obtained thickness data. Among the thicknesses in the thickness data, the maximum thickness is treated as the maximum thickness, and the minimum thickness is treated as the minimum thickness. The thickness (average thickness) of the support film may also be derived in a similar manner. Catalog values ​​for the thickness of the support film may be used as a reference.

[0104] In one embodiment, the difference between the maximum thickness and the minimum thickness of the photosensitive resin layer is less than 5%, less than 3%, or less than 1% of the average thickness of the photosensitive resin layer. This means that the photosensitive resin layer has small thickness variation. The thickness variation is calculated using the following formula: Thickness variation (%) = 100 × (maximum thickness - minimum thickness) / (average thickness).

[0105] [Method for forming a resist pattern] Another aspect of this embodiment is a method for forming a resist pattern using a photosensitive element roll. The method for forming a resist pattern includes: a step of pulling out a photosensitive element from the photosensitive element roll and laminating a photosensitive resin layer of the photosensitive element onto a substrate (lamination step); a step of exposing the laminated photosensitive resin layer (exposure step); and a step of removing unexposed areas (in the case of a negative type) or exposed areas (in the case of a positive type) of the photosensitive resin layer with an alkaline aqueous solution to form a resist pattern (development step), and may optionally include at least one of a step of heating the photosensitive resin layer after exposure (and before development) (post-exposure baking step); or a step of heating the resist pattern after development (post-development baking step).

[0106] <Lamination Step> In this step, the photosensitive element is pulled out from the photosensitive element roll, and the photosensitive resin layer of the photosensitive element is laminated onto the substrate. If the photosensitive element has a protective film, the photosensitive resin layer is laminated onto the substrate while peeling off the protective film. At this time, the photosensitive resin layer is adhered to the substrate using, for example, a hot roll laminator. The substrate is preferably a silicon wafer with a copper layer formed on it using a sputtering device (copper-sputtered silicon wafer).

[0107] <<Exposure Step>> In this step, the laminated photosensitive resin layer is exposed to light. This step may be performed by using any of the following methods: a method of exposing the photosensitive resin layer laminated on the substrate through a mask film with the mask film having a desired wiring pattern in close contact with the photosensitive resin layer; a method of exposing the desired wiring pattern by a direct imaging exposure method; or a method of exposing by an exposure method in which an image of a photomask is projected through a lens.

[0108] <Post-Exposure Baking Step> In this step, the photosensitive resin layer may be heated after exposure (and before development). This step may be performed by heating the exposed substrate at about 40 to 180°C for 1 to 10 minutes. By performing this step, it is possible to further improve the adhesion and chemical resistance of the resulting resist pattern. For heating, for example, a heating furnace using hot air, infrared rays, far infrared rays, or the like may be used.

[0109] <Development Step> In this step, the unexposed areas (in the case of a negative type) or the exposed areas (in the case of a positive type) of the photosensitive resin layer are removed using an alkaline aqueous solution, thereby forming a resist pattern. This step may be performed by peeling the support film from the photosensitive resin layer, and removing the unexposed areas (in the case of a negative type) or the exposed areas (in the case of a positive type) using a developer that is an alkaline aqueous solution. The alkaline aqueous solution is appropriately selected depending on the properties of the photosensitive resin layer, and may be, for example, Na ２ CO ３ or K ２ CO ３ More specifically, an aqueous solution of Na ２ CO ３ Examples include aqueous solutions.

[0110] <Post-development heating step> In this step, the resist pattern may be heated after development. This step may be carried out by heating the resist pattern, for example, at about 100 to 300°C for 1 minute to 5 hours. By carrying out this step, it is possible to further improve the adhesion and chemical resistance of the resist pattern. For heating, for example, a heating furnace using hot air, infrared rays, far infrared rays, or the like may be used.

[0111] [Method for forming a conductive pattern] Another aspect of this embodiment is a method for forming a conductive pattern using a photosensitive element roll. Examples of the conductive pattern include copper pillars or bumps for semiconductor bonding. The method for forming a conductive pattern includes: a step of obtaining a substrate with a resist pattern; a step of copper-plating or solder-plating the substrate with the resist pattern to obtain a substrate with a conductive pattern (plating step); and, optionally, may include at least one of the following steps: a step of performing descum treatment and / or plating pretreatment on the substrate with the resist pattern before the plating step (descum and plating pretreatment); and a step of peeling the resist pattern from the substrate with the conductive pattern after the plating step (peeling step).

[0112] <<Descum and Plating Pretreatment>> In this step, the substrate having the resist pattern is subjected to descum treatment and / or plating pretreatment. This step may be performed by subjecting the substrate having the resist pattern to plasma treatment and / or water immersion treatment. The treatment times may be appropriately selected depending on the surface condition of the substrate, the level of resist residue, etc.

[0113] <Plating Step> In this step, the substrate with the resist pattern is copper-plated or solder-plated. This allows a conductive pattern to be formed. This step may be performed by copper-plating or solder-plating the substrate surface exposed by development (for example, the copper surface when the substrate is a copper-sputtered silicon wafer). The plating solution is preferably a copper sulfate plating solution.

[0114] <<Removal Step>> In this step, after the plating step, the resist pattern is removed from the substrate having a conductive pattern. This step may be performed by treating the resist pattern with an aqueous solution (removal solution) that is more alkaline than the developer, thereby removing the resist pattern from the substrate. The remover solution is preferably at least one selected from the group consisting of an aqueous NaOH solution or an aqueous KOH solution, an organic amine-based aqueous solution, SPR920 (product name), and R-101 (product name), each having a concentration of about 2 to 5% by mass and a temperature of about 40 to 70°C. The remover solution may contain a small amount of a water-soluble solvent. The removal time is preferably about twice the removal time measured using a sample obtained by full-surface exposure.

[0115] The photosensitive element, resist pattern, copper pillar and semiconductor bump described above can be used, for example, to form a semiconductor package.

[0116] [Other Embodiments] The present invention is not limited to the above-described embodiments and can be practiced with various modifications within the scope of the present invention. The (A) support film and the (B) photosensitive resin layer may each be composed of a single layer or multiple layers. If the photosensitive element roll has other layers (e.g., an intermediate layer and a release layer) in addition to the (A) support film, the (B) photosensitive resin layer, and the (C) protective film, the thicknesses of these other layers are not included in the thicknesses of (A) to (C).

[0117] The (A) support film functions as a support when laminating the photosensitive element to a substrate, and the (C) protective film functions to protect the surface of the photosensitive resin layer to be laminated to the substrate. In this regard, a photosensitive element is assumed that includes a first film, a photosensitive resin layer, and a second film in this order, the first film and the second film respectively constituting the outermost layers, and both the first film and the second film can also be used as a support film. In such a photosensitive element, the support film arranged on the opposite side of the surface of the photosensitive resin layer to be laminated to the substrate, i.e., the first film when the exposed surface of the photosensitive resin layer exposed by peeling the second film is laminated to the substrate; the second film when the exposed surface of the photosensitive resin layer exposed by peeling the first film is laminated to the substrate, is treated as the (A) support film. In this case, the film that is not treated as (A) the support film may be treated as (C) the protective film.

[0118] Furthermore, when the photosensitive element roll has a (C) protective film, in one embodiment, the adhesive strength between the (C) protective film and the photosensitive resin layer is smaller than the adhesive strength between the (A) support film and the photosensitive resin layer.

[0119] Examples 1 to 26 and Comparative Examples 1 to 6 Photosensitive Element and Photosensitive Element Roll The materials shown in the table below were weighed out in the proportions (parts by mass) shown in the table, and then stirred at 35°C for 5 hours or more to obtain a coating solution of a photosensitive resin composition. The obtained coating solution was sent to a slot die coater through a liquid feed line. The slot die coater was then used to coat various PET films shown in the table below while transporting them, thereby forming a coating film on the film. The temperature (drying temperature) and film transport speed were selected so that the proportion of solvent remaining in the coating film was 3% by mass or less relative to the coating film. Photosensitive elements were thus obtained. The average thickness and thickness variation of the photosensitive resin layer were the values ​​shown in the table below. Furthermore, the thickness variation of the support film was 3% or less in all cases.

[0120] The average thickness of the PET film and the photosensitive resin layer was measured to two significant digits using the same method. The maximum height and minimum height were also measured using the same method, and the thickness variation (%) was calculated.

[0121] Here, after the drying, the surface of the photosensitive resin layer and a 19 μm thick polyethylene film (GF-18, manufactured by Tamapoly Co., Ltd.) were in-line pressure-bonded using nip rolls to form a laminate, which was treated as a photosensitive element. In this photosensitive element, the PET film functions as a support (support film), and the polyethylene film functions as a protective layer (protective film).

[0122] An FRP core having an outer diameter of about 200 mm was used as the core, and the protective film side was positioned on the inner side (core side), and 400 m of the photosensitive element was wound around the core, thereby obtaining photosensitive element rolls (Examples and Comparative Examples). The size of these photosensitive element rolls was approximately 1600 mm in width and 380 mm in outer diameter (including the core).

[0123] [Measurement and Evaluation] <Evaluation Substrate> <Substrate> As a substrate, a wafer (copper-sputtered silicon wafer) was prepared by forming a copper layer of 2000 angstroms (Å) thick on a 6-inch silicon wafer using a sputtering apparatus (L-440S-FHL) manufactured by Canon Anelva Corporation.

[0124] <Lamination> While peeling the polyethylene film from the photosensitive element, the photosensitive element was laminated onto a substrate preheated to 70° C. using an air damper type hot roll laminator (VA-400III, manufactured by Taisei Laminator Co., Ltd.) at a roll temperature of 70° C. The air pressure was set to 0.20 MPa and the lamination speed was set to 0.18 m / min.

[0125] <Exposure> A glass chrome mask was prepared in which circular patterns with a diameter of 150 μm (patterns in which the outside of the circles are exposed and the inside of the circles are not exposed to the photosensitive material) were arranged in a grid pattern (300 μm pitch in the X direction and 300 μm pitch in the Y direction). The photosensitive resin layer was exposed using an Ultratech Prisma ghi stepper (manufactured by Ultratech) at an exposure dose such that the dimensional difference between the diameter of the circular patterns of this mask (150 μm) and the diameter of the resist pattern measured after development (diameter of the openings on the surface of the photosensitive resin layer) was ±10%. The illuminance measured on the substrate surface was 2400 mW / cm. ２ It was.

[0126] <Development> After the above <Exposure>, the PET film was peeled off from the substrate, and then a 1% by mass Na ２ CO ３ The aqueous solution was sprayed onto the photosensitive resin layer at a liquid temperature of 30°C and a flow rate of 200 mL / min (spray development). For each experimental example, the minimum development time under the above conditions was determined in advance, and twice the minimum development time was set as the development time. The "minimum development time" refers to the shortest time required for the unexposed portions of the photosensitive resin layer to completely dissolve. After development, water was sprayed onto the photosensitive resin layer (water wash spray). The conditions and time for the water wash spray were set the same as for the development spray.

[0127] <Descum treatment and plating pretreatment> A low-pressure plasma device (EXAM, manufactured by Shinko Seiki Co., Ltd.) was used to treat the metal surface with 50 Pa, 133 W, and O ２ 40mL / min, CF ４ The resist pattern was subjected to plasma treatment (descum treatment and plating pretreatment) under conditions of 1 mL / min and 1500 seconds.

[0128] <Copper sulfate plating> 968 mL of SC-50 MU MA (manufactured by MICROFAB®), 20 mL of SC-50 R1 (manufactured by MICROFAB®), and 12 mL of SC-50 R2 (manufactured by MICROFAB®) were mixed to obtain a copper sulfate plating solution. Using the obtained copper sulfate plating solution, a Haring Cell uniform plating apparatus (manufactured by Yamamoto Plating Tester Co., Ltd.) was used to copper-plat the substrate (6 cm × 12.5 cm) that had been subjected to the above-described <Descum treatment and plating pretreatment>.> The current value was adjusted so that copper was deposited at a height (thickness) of 1 μm per minute. This resulted in a copper plating film.

[0129] The plating time was adjusted so that the average thickness of the copper plating film (average plating thickness) was 10 μm less than the average thickness of the resist pattern after plasma treatment. The thickness of the resist pattern and the plating thickness were measured using an XYZ digital counter of an optical microscope. The height from the substrate surface to the focal point of the resist surface and the plating surface was defined as each thickness, and the thickness was measured at five arbitrary measurement points, and these were averaged. The calculated average values ​​for the resist pattern thickness and the plating thickness were treated as the average resist pattern thickness and the average plating thickness, respectively.

[0130] <Removal> After the copper sulfate plating, the substrate was heated at 65°C for 70 minutes using a stripping solution of SPR920 (manufactured by KANTO-PPC). The substrate was then rinsed with water for 50 seconds and air-dried. This produced a substrate from which at least a portion of the resist pattern had been peeled, and this was used as an evaluation substrate. In the evaluation substrate, the copper plating film remaining after <Removal> functions as copper pillars for wiring.

[0131] [Evaluation Method] The examples and comparative examples were evaluated based on the following evaluation criteria. When multiple criteria are met, the criteria closest to "F" is given priority.

[0132] <Storage Stability of Photosensitive Element Roll> The appearance of each of the photosensitive element rolls (Examples and Comparative Examples) was visually inspected after storage at 5°C for 6 months, and the storage stability of the photosensitive element roll was evaluated by ranking it as follows:

[0133] Evaluation criteria: F: An uneven appearance is observed over the entire roll surface, and shearing is observed. E: No shearing is observed, but an uneven appearance is observed over the entire roll surface. D: An uneven appearance is observed on part of the roll surface, and shearing is observed. C: No shearing is observed, but an uneven appearance is observed on part of the roll surface. B: Almost no uneven appearance is observed on the roll surface, and almost no shearing is observed. A: No uneven appearance is observed on the roll surface, and no shearing is observed.

[0134] Here, "an uneven appearance is observed over the entire roll surface" corresponds to, for example, a case where irregularities are observed over the entire roll surface; "an uneven appearance is observed on a part of the roll surface" corresponds to, for example, a case where lumps (gauge bands) are observed on a part of the roll surface; and "winding deviation is observed" corresponds to, for example, a case where protrusions in the width direction are observed from the end face of the roll. Of these, a grade of "C" or higher may be regarded as passing.

[0135] <<Releasability>> The residual rate of the photosensitive resin layer that could remain on the evaluation substrate after the <<peeling>> (i.e., that was not completely peeled off during the <<peeling>>) was calculated, and the residual rate was ranked as follows to evaluate the releasability. Specifically, a 5 cm x 5 cm area of ​​the evaluation substrate after the <<peeling>> was observed using an optical microscope. Here, the horizontally projected area of ​​the photosensitive resin layer before the <<peeling>> and the horizontally projected area of ​​the photosensitive resin layer after the <<peeling>> (the photosensitive resin layer that was not completely peeled off) were calculated. The residual rate (%) was calculated using the following formula: residual rate (%) = (horizontal projected area of ​​the photosensitive resin layer that was not completely peeled off) / (horizontal projected area of ​​the photosensitive resin layer before peeling). The residual rate (%) was calculated for five different observation areas, and the average value was used to evaluate the <<peeling ability>>.

[0136] Evaluation criteria: F: The residual rate is 15% or more E: The residual rate is 10% or more but less than 15% D: The residual rate is 5% or more but less than 10% C: The residual rate is 1% or more but less than 5% B: The residual rate is less than 1%, but there are confirmed areas where residual peeling (photosensitive resin layer that was not completely peeled off) is observed at the foot (bottom) of some copper pillars A: In all observation areas, residual peeling (photosensitive resin layer that was not completely peeled off) is not observed throughout the entire area, including the foot (bottom) of the copper pillar Of these, a grade of "C" or higher may be considered a pass.

[0137] <Copper pillar formability> After the above <peeling>, an area of ​​5 cm x 5 cm of the evaluation substrate was observed using an optical microscope. Here, the degree to which protrusions of 10 μm or more and / or chips of 10 μm or more were confirmed in the formed copper pillars was evaluated, and the degree to which the protrusions and chips were confirmed was ranked as follows to evaluate the copper pillar formability. The degree to which the protrusions and chips were confirmed was determined in five arbitrary different observation areas, and the average value was used to evaluate the <copper pillar formability>.

[0138] Evaluation criteria: F: Protrusions and / or chips are observed on 50% or more of the copper pillars. E: Protrusions and / or chips are observed on 30% or more but less than 50% of the copper pillars. D: Protrusions and / or chips are observed on 10% or more but less than 30% of the copper pillars. C: Protrusions and / or chips are observed on 5% or more but less than 10% of the copper pillars. B: Protrusions and / or chips are observed on 0.1% or more but less than 5% of the copper pillars. A: Protrusions and / or chips were observed on less than 0.1% of the copper pillars. Of these, those rated "C" or higher may be considered to have particularly excellent copper pillar formability.

[0139] An embodiment that gives a favorable evaluation in <<Copper pillar formability>> may be regarded as an embodiment that has excellent formability of the conductor pattern, and may also be regarded as an embodiment that has excellent formability of the bumps included in such conductor pattern.

[0140]

[0141]

[0142]

[0143]

[0144] The photosensitive element and photosensitive element roll of the present disclosure can be used to form resist patterns, copper pillars for semiconductors, bumps, etc. The resist patterns, copper pillars for semiconductors, bumps, etc. can be used, for example, to form semiconductor packages.

Claims

1. A photosensitive element roll formed by winding a photosensitive element having (A) a support film, and (B) a photosensitive resin layer containing a photosensitive resin composition, wherein the average thickness of the (A) support film is 27 μm or more, the average thickness of the (B) photosensitive resin layer is 150 μm or more, and the photosensitive resin composition contains the following components: (B1) an alkali-soluble polymer, (B2) a photopolymerizable compound, and (B3) a photopolymerization initiator.

2. The photosensitive element roll according to claim 1, wherein the average thickness of the support film (A) is 38 μm or more.

3. The photosensitive element roll according to claim 1, wherein the difference between the maximum thickness and the minimum thickness of said photosensitive resin layer (B) is less than 5% of the average thickness of said photosensitive resin layer (B).

4. A photosensitive element roll formed by winding a photosensitive element having (A) a support film, and (B) a photosensitive resin layer containing a photosensitive resin composition, wherein the average thickness of the (B) photosensitive resin layer is 150 μm or more, the difference between the maximum thickness and the minimum thickness of the (B) photosensitive resin layer is less than 5% of the average thickness of the (B) photosensitive resin layer, and the photosensitive resin composition contains the following components: (B1) an alkali-soluble polymer, (B2) a photopolymerizable compound, and (B3) a photopolymerization initiator.

5. The photosensitive element roll according to claim 4, wherein the difference between the maximum thickness and the minimum thickness of the photosensitive resin layer (B) is less than 3% of the average thickness of the photosensitive resin layer (B).

6. The photosensitive element roll according to claim 4, wherein the difference between the maximum thickness and the minimum thickness of the photosensitive resin layer (B) is less than 1% of the average thickness of the photosensitive resin layer (B).

7. The photosensitive element roll according to any one of claims 1 to 6, wherein the average thickness of the photosensitive resin layer (B) is 250 µm or more.

8. The photosensitive element roll according to any one of claims 1 to 6, wherein the average thickness of the photosensitive resin layer (B) is 300 µm or more.

9. The photosensitive element roll according to any one of claims 1 to 6, wherein the support film (A) is a polyester film.

10. The photosensitive element roll according to any one of claims 1 to 6, wherein the support film (A) is a polyethylene terephthalate (PET) film having a haze of 2.0% or less.

11. The photosensitive element roll according to any one of claims 1 to 6, wherein the support film (A) is a polyethylene terephthalate (PET) film having a haze of 1.0% or less.

12. Observation area of ​​the support film (A) is 10,000 mm ２ The photosensitive element roll according to any one of claims 1 to 6, wherein the number of foreign particles having a maximum diameter of 10 µm or more contained therein is 100 or less.

13. Observation area of ​​the support film (A) is 10,000 mm ２ The photosensitive element roll according to any one of claims 1 to 6, wherein the number of foreign objects having a maximum diameter of 10 µm or more contained therein is 40 or less.

14. The photosensitive element roll according to any one of claims 1 to 6, wherein the mass ratio of the component (B1) to the component (B2) {(B1) / (B2)} is 1.1 to 2.

0.

15. The photosensitive element roll according to any one of claims 1 to 6, wherein the component (B1) is a copolymer of: (B1-1) a compound having a carboxy group and an ethylenically unsaturated bond; and (B1-2) another compound having an ethylenically unsaturated bond.

16. The photosensitive element roll according to any one of claims 1 to 6, wherein the weight average molecular weight of the component (B1) is 20,000 to 70,000.

17. The photosensitive element roll according to any one of claims 1 to 6, wherein the component (B2) is a compound having a (meth)acryloyl group.

18. The photosensitive element roll according to any one of claims 1 to 6, comprising an imidazole compound as the component (B3).

19. The photosensitive element roll according to any one of claims 1 to 6, wherein the photosensitive element further comprises a protective film (C) on the opposite side of the photosensitive resin layer (B) from the support film (A), and the protective film (C) is selected from the group consisting of polyester films, polypropylene films, and polyethylene films.

20. The photosensitive element roll according to claim 19, wherein the protective film (C) is a polyethylene film.

21. The photosensitive element roll according to any one of claims 1 to 6, wherein the outer diameter of the end face in the longitudinal direction of the photosensitive element roll has a circularity of 5 to 500 µm.

22. The photosensitive element roll according to any one of claims 1 to 6, wherein the photosensitive element roll is formed by winding the photosensitive element around a core, and the average thickness of the (A) support film relative to the outer diameter (μm) of the core {average thickness of (A) support film / outer diameter of core} is 0.000135 or more, and the average thickness of the (B) photosensitive resin layer relative to the outer diameter (μm) of the core {average thickness of (B) photosensitive resin layer / outer diameter of core} is 0.00075 or more.

23. The photosensitive element roll according to any one of claims 1 to 6, wherein the average thickness of the support film (A) is 100 μm or less, and / or the average thickness of the photosensitive resin layer (B) is 800 μm or less.

24. A method for forming a resist pattern, comprising: a lamination step of laminating the photosensitive resin layer (B) of the photosensitive element roll according to any one of claims 1 to 6 onto a substrate; an exposure step of exposing the photosensitive resin layer (B) to light; and a development step of removing unexposed areas of the photosensitive resin layer (B) with an alkaline aqueous solution.

25. A method for forming a conductor pattern, comprising: obtaining a substrate with a resist pattern by the method described in claim 24; plating the substrate with the resist pattern with a metal to obtain a substrate with a conductor pattern; and peeling the resist pattern from the substrate with the conductor pattern using a stripping solution.

26. The method for forming a conductor pattern according to claim 25, wherein the conductor pattern is a copper pillar or bump.

27. A photosensitive element having (A) a support film, and (B) a photosensitive resin layer containing a photosensitive resin composition, wherein the (A) support film has an average thickness of 27 μm or more, the (B) photosensitive resin layer has an average thickness of 150 μm or more, the photosensitive resin composition contains the following components: (B1) an alkali-soluble polymer, (B2) a photopolymerizable compound, and (B3) a photopolymerization initiator, and the (B1) component is a copolymer of (B1-1) a compound having a carboxy group and an ethylenically unsaturated bond, and (B1-2) another compound having an ethylenically unsaturated bond.

28. A photosensitive element having (A) a support film, and (B) a photosensitive resin layer containing a photosensitive resin composition, wherein the average thickness of the (B) photosensitive resin layer is 150 μm or more, and the difference between the maximum thickness and the minimum thickness of the (B) photosensitive resin layer is less than 5% of the average thickness of the (B) photosensitive resin layer, and the photosensitive resin composition contains the following components: (B1) an alkali-soluble polymer, (B2) a photopolymerizable compound, and (B3) a photopolymerization initiator, and the (B1) component is a copolymer of (B1-1) a compound having a carboxy group and an ethylenically unsaturated bond, and (B1-2) another compound having an ethylenically unsaturated bond.

Images