Photosensitive resin composition, photosensitive element, printed wiring board, and method for producing printed wiring board

Abstract

The present invention relates to a photosensitive resin composition for a permanent resist, which contains (A) an acid-modified vinyl-containing resin, (B) an epoxy compound, (C) a photopolymerization initiator, (D) a photopolymerizable compound and (F) an inorganic filler, and wherein: the equivalence ratio of an epoxy group contained in the epoxy compound (B) to a carboxyl group contained in the acid-modified vinyl-containing resin (A) is 1.25-7.5; the inorganic filler (F) includes a silica filler having a vinyl group derived from a vinylsilane compound.

Description

Technical Field

[0001] The present invention relates to a photosensitive resin composition for permanent resist, a photosensitive element, a printed circuit board and a method for producing the printed circuit board. Background Art

[0002] In the field of printed wiring boards, a process of forming a permanent resist on a printed wiring board is being carried out. The permanent resist has the function of preventing corrosion of a conductor layer or maintaining electrical insulation between conductor layers when the printed wiring board is used. In recent years, the permanent resist has also played the role of a solder resist film in the process of flip-chip mounting or wire bonding mounting of a semiconductor element on a printed wiring board via solder, thereby preventing solder from adhering to unnecessary parts of the conductor layer of the printed wiring board.

[0003] In the past, permanent resists were produced by screen printing using a thermosetting resin composition or by photographic methods using a photosensitive resin composition. For example, in flexible circuit boards using mounting methods such as FC (Flip Chip), TAB (Tape Automated Bonding), and COF (Chip On Film), in addition to IC chips, electronic parts or LCD (Liquid Crystal Display) panels and connection wiring pattern parts, thermosetting resin pastes are screen printed and thermally cured to form permanent resists (for example, refer to Patent Document 1).

[0004] In semiconductor package substrates such as BGA (ball grid array) and CSP (chip size package) mounted on electronic parts, (1) in order to flip-chip mount the semiconductor element on the semiconductor package substrate via solder, (2) in order to wire-bond the semiconductor element to the semiconductor package substrate, and (3) in order to solder the semiconductor package substrate to the motherboard substrate, it is necessary to remove the permanent resist at the bonding portion. In the image formation of the permanent resist, a photographic method is used in which, after applying and drying a photosensitive resin composition, active light such as ultraviolet rays is selectively irradiated to cure it, and only the unirradiated portion is removed by development to form an image. The photographic method is suitable for mass production because of its good operability, and is therefore widely used in the electronic materials industry for image formation of photosensitive materials (for example, refer to Patent Document 2).

[0005] Previous technical literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2003-198105

[0008] Patent Document 2: Japanese Patent Application Laid-Open No. 11-240930 Summary of the invention

[0009] Technical issues to be solved by the invention

[0010] On the other hand, permanent resists formed from conventional photosensitive resin compositions may sometimes generate cracks in the permanent resists under harsh environments such as high temperatures, and thus a photosensitive resin composition capable of forming a permanent resist having excellent crack resistance is desired. In addition, when a permanent resist is formed using conventional photosensitive resin compositions, resist residues may sometimes be generated after development, which may cause fatal defects when connected to bumps of a chip, and thus a photosensitive resin composition having excellent developability is desired.

[0011] Therefore, an object of the present invention is to provide a photosensitive resin composition for a permanent resist which can form a permanent resist having excellent crack resistance and excellent developability, a photosensitive element using the photosensitive resin composition, a printed wiring board, and a method for producing a printed wiring board.

[0012] Means for solving technical problems

[0013] Some aspects of the present invention provide the following [1] to [9].

[0014] [1] A photosensitive resin composition for a permanent resist, comprising: (A) an acid-modified vinyl-containing resin, (B) an epoxy compound, (C) a photopolymerization initiator, (D) a photopolymerizable compound, and (F) an inorganic filler, wherein the equivalent ratio of the epoxy group contained in the epoxy compound (B) to the carboxyl group contained in the acid-modified vinyl-containing resin (A) is 1.25 to 7.50, and the inorganic filler (F) comprises a silica filler having a vinyl group derived from a vinyl silane compound.

[0015] [2] The photosensitive resin composition according to [1] above, wherein

[0016] The above-mentioned equivalent ratio is 2.00 to 7.50.

[0017] [3] The photosensitive resin composition according to [1] above, wherein

[0018] The above-mentioned equivalent ratio is 2.50 to 7.50.

[0019] [4] The photosensitive resin composition according to any one of [1] to [3] above, further comprising (E) a pigment.

[0020] [5] A photosensitive element comprising a support film and a photosensitive layer formed on the support film, wherein the photosensitive layer contains the photosensitive resin composition according to any one of [1] to [4] above.

[0021] [6] A printed wiring board comprising a permanent resist containing a cured product of the photosensitive resin composition according to any one of [1] to [4] above.

[0022] [7] The printed wiring board according to [6] above, wherein:

[0023] The thickness of the permanent resist is 10 to 50 μm.

[0024] [8] A method for manufacturing a printed wiring board, comprising: a step of forming a photosensitive layer on a substrate using the photosensitive resin composition described in any one of [1] to [4] above; a step of exposing and developing the photosensitive layer to form a resist pattern; and a step of curing the resist pattern to form a permanent resist.

[0025] [9] A method for manufacturing a printed wiring board, comprising: a step of forming a photosensitive layer on a substrate using the photosensitive element described in [5] above; a step of exposing and developing the photosensitive layer to form a resist pattern; and a step of curing the resist pattern to form a permanent resist.

[0026] Effects of the Invention

[0027] According to the present invention, a photosensitive resin composition for a permanent resist which can form a permanent resist having excellent crack resistance and excellent developability, a photosensitive element using the photosensitive resin composition, a printed wiring board, and a method for producing a printed wiring board can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a cross-sectional view schematically showing the photosensitive element of this embodiment. DETAILED DESCRIPTION

[0029] Hereinafter, an embodiment of the present invention will be specifically described, but the present invention is not limited thereto. In the following embodiments, unless otherwise expressly stated or clearly considered to be necessary in principle, the constituent elements (including element steps, etc.) are not essential. The same is true for numerical values ​​and their ranges, and the present invention is not improperly limited.

[0030] In the present invention, the term "layer" includes not only a structure of a shape formed on the entire surface, but also a structure of a shape formed on a part thereof when viewed from a top view. In the present invention, the term "process" includes not only an independent process, but also a process that achieves the intended purpose of the process even if it cannot be clearly distinguished from other processes. In the present invention, the numerical range represented by "~" represents a range that includes the numerical values ​​recorded before and after "~" as the minimum and maximum values, respectively. In the numerical range recorded in stages in the present invention, the upper limit or lower limit of the numerical range of a certain stage can be replaced by the upper limit or lower limit of the numerical range of other stages. In addition, in the numerical range recorded in the present invention, the upper limit or lower limit of the numerical range can be replaced by the value shown in the embodiment. In the present invention, "A or B" includes either A or B, or both. With regard to the materials exemplified below, as long as there is no special explanation, one kind can be used alone, or two or more kinds can be used in combination. In the present invention, when a plurality of substances corresponding to each component are present in the composition, the content of each component in the composition refers to the total amount of the plurality of substances present in the composition unless otherwise specified.

[0031] In the present invention, "solid content" refers to non-volatile components obtained by removing volatile substances such as water and diluent contained in the photosensitive resin composition, and means components that evaporate or remain without volatilization when the resin composition is dried, and also includes components that are liquid, syrupy or waxy at room temperature (25°C, the same below).

[0032] [Photosensitive resin composition]

[0033] The photosensitive resin composition of the present embodiment contains: (A) an acid-modified vinyl-containing resin, (B) an epoxy compound, (C) a photopolymerization initiator, (D) a photopolymerizable compound, and (F) an inorganic filler, wherein the equivalent ratio of the epoxy group contained in the (B) epoxy compound to the carboxyl group contained in the (A) acid-modified vinyl-containing resin (equivalent ratio of epoxy group / carboxyl group, molar ratio) is 1.25 to 7.50, and the (F) inorganic filler includes a silica filler having a vinyl group derived from a vinyl silane compound. The photosensitive resin composition of the present embodiment is a negative photosensitive resin composition, and a cured product of the photosensitive resin composition can be used as a permanent resist. The present inventors have found that when the epoxy group / carboxyl group equivalent ratio is 1.25 or more, the epoxy group derived from the epoxy compound is present in greater amounts than the carboxyl group derived from the acid-modified vinyl-containing resin, and the elasticity of the permanent resist formed thereby tends to be good, thereby improving the crack resistance of the permanent resist. However, as the epoxy group / carboxyl group equivalent ratio increases, the solubility of the formed cured product in a developer decreases, and there is a tendency for the developability to decrease. The present inventors have found that by using a silica filler having a vinyl group derived from a vinyl silane compound as an inorganic filler in combination, the silica filler having a vinyl group derived from a vinyl silane compound is more likely to be developed by bonding to a functional group such as a vinyl group contained in an acid-modified vinyl-containing resin, a photopolymerizable compound, etc. in a photosensitive resin composition compared to other silica fillers, and therefore, even if the epoxy group / carboxyl group equivalent ratio is high, the solubility of the formed cured product in a developer can be suppressed from decreasing, and the developability can be improved, thereby completing the present invention.

[0034] The photosensitive resin composition of the present embodiment can form a permanent resist with excellent crack resistance, and can reduce the generation of residue after development, so the developability is also excellent. In addition, the photosensitive resin composition of the present embodiment can form a permanent resist with excellent fluidity and excellent adhesion to the copper substrate. In addition, the photosensitive resin composition of the present embodiment is also excellent in the performance (for example, resolution, electrical insulation, solder heat resistance, solvent resistance, acid resistance and alkali resistance) required for the photosensitive resin composition for manufacturing a printed wiring board. Below, each component contained in the photosensitive resin composition of the present embodiment is described in detail.

[0035] <Component (A): Acid-modified vinyl-containing resin>

[0036] The photosensitive resin composition of the present embodiment contains an acid-modified vinyl-containing resin as the component (A). The acid-modified vinyl-containing resin is not particularly limited as long as it has a vinyl bond which is a photopolymerizable ethylenically unsaturated bond and an alkali-soluble acidic group.

[0037] As the group having the ethylenically unsaturated bond possessed by the component (A), for example, a vinyl group, an allyl group, a propargyl group, a butenyl group, an ethynyl group, a phenylethynyl group, a maleimide group, a nadic imide group, and a (meth)acryloyl group can be cited. Among them, from the viewpoint of reactivity and resolution, a (meth)acryloyl group can be cited. As the acidic group possessed by the component (A), for example, a carboxyl group, a sulfo group, and a phenolic hydroxyl group can be cited. Among them, from the viewpoint of resolution, a carboxyl group can be cited.

[0038] The (A) component may be an acid-modified vinyl-containing epoxy derivative obtained by reacting (a) an epoxy resin (hereinafter sometimes referred to as the "(a) component") and (b) an organic acid containing an ethylenically unsaturated group (hereinafter sometimes referred to as the "(b) component"), and (A') (hereinafter sometimes referred to as the "(A') component") with (c) a polyacid anhydride containing a saturated or unsaturated group (hereinafter sometimes referred to as the "(c) component").

[0039] Examples of the acid-modified vinyl-containing epoxy derivative include acid-modified epoxy (meth) acrylates. Acid-modified epoxy (meth) acrylates are resins obtained by acid-modifying epoxy (meth) acrylates, which are reactants of components (a) and (b), with component (c). Examples of the acid-modified epoxy (meth) acrylates include addition reaction products obtained by adding saturated or unsaturated polybasic acid anhydrides to esters obtained by reacting epoxy resins with vinyl-containing monocarboxylic acids.

[0040] As the component (A), for example, an acid-modified vinyl-containing resin (A1) (hereinafter sometimes referred to as "component (A1)") obtained by using a bisphenol novolac epoxy resin (a1) (hereinafter sometimes referred to as "epoxy resin (a1)") as the component (a) and an acid-modified vinyl-containing resin (A2) (hereinafter sometimes referred to as "component (A2)") obtained by using an epoxy resin (a2) other than the epoxy resin (a1) (hereinafter sometimes referred to as "epoxy resin (a2)") as the component (a) can be mentioned. These can be used alone or in combination of two or more.

[0041] (Epoxy resin (a1))

[0042] Examples of the epoxy resin (a1) include epoxy resins having a structural unit represented by the following formula (I) or (II). The epoxy resin (a1) may be an epoxy resin having a structural unit represented by the formula (I).

[0043]

[0044] In formula (I), R 11 Represents a hydrogen atom or a methyl group, multiple R 11Can be the same or different. 1 and Y 2 Each independently represents a hydrogen atom or a glycidyl group, but Y 1 and Y 2 At least one of them is a glycidyl group.

[0045] From the perspective of improving resolution, R 11 can be a hydrogen atom, Y 1 and Y 2 It may be a glycidyl group.

[0046] The number of structural units of the structural unit represented by formula (I) in the epoxy resin (a1) is 1 or more, and can be 10 to 100, 15 to 80, or 15 to 70. If the number of structural units is within the above range, it is easy to improve heat resistance and electrical insulation. Here, the number of structural units represents an integer value in a single molecule, and represents a rational number as an average value in an aggregate of multiple molecules (hereinafter, the same).

[0047]

[0048] In formula (II), R 12 Represents a hydrogen atom or a methyl group, multiple R 12 Can be the same or different. 3 and Y 4 Each independently represents a hydrogen atom or a glycidyl group, but Y 3 and Y 4 At least one of them is a glycidyl group.

[0049] From the perspective of improving resolution, R 12 can be a hydrogen atom, Y 3 and Y 4 It may be a glycidyl group.

[0050] The number of structural units represented by formula (II) in the epoxy resin (a1) is 1 or more, and may be 10 to 100, 15 to 80, or 15 to 70. When the number of structural units is within the above range, heat resistance and electrical insulation properties are easily improved.

[0051] In formula (II), R 12 is a hydrogen atom and Y 3 and Y 4 The epoxy resin which is a glycidyl group is commercially available as EXA-7376 series (manufactured by DIC Corporation, trade name). 12 is methyl and Y 3 and Y 4The epoxy resin which is a glycidyl group is commercially available as EPON SU8 series (manufactured by Mitsubishi Chemical Corporation, trade name).

[0052] (Epoxy resin (a2))

[0053] The epoxy resin (a2) is not particularly limited as long as it is an epoxy resin different from the epoxy resin (a1), and may be at least one selected from the group consisting of novolac epoxy resins, bisphenol A epoxy resins, bisphenol F epoxy resins, trisphenol methane epoxy resins, and biphenyl epoxy resins.

[0054] As the epoxy resin (a2), for example, a bisphenol A epoxy resin or a bisphenol F epoxy resin having a structural unit represented by the following formula (III) can be cited. As the epoxy resin having such a structural unit, for example, a bisphenol A epoxy resin or a bisphenol F epoxy resin represented by the following formula (III') can be cited.

[0055]

[0056] In formula (III) and (III'), R 13 Represents a hydrogen atom or a methyl group, and there are multiple R 13 Can be the same or different, Y 5 In formula (III'), n2 represents a number greater than 1. When n2 is greater than 2, multiple Y 5 Can be the same or different, at least one Y 5 It is a glycidyl group.

[0057] From the perspective of improving resolution, R 13 From the viewpoint of further improving crack resistance, Y 5 It may be a glycidyl group. n2 represents 1 or more, but may be 10 to 100, 10 to 80, or 15 to 60. When n2 is within the above range, the linearity and heat resistance of the resist pattern profile are easily improved.

[0058] Y in formula (III) 5 A bisphenol A epoxy resin or a bisphenol F epoxy resin which is a glycidyl group can be obtained by, for example, making Y in formula (III) 5 The hydroxyl group of bisphenol A epoxy resin or bisphenol F epoxy resin is a hydrogen atom (-OY 5 ) is obtained by reaction with epichlorohydrin.

[0059] To promote the reaction between hydroxyl and epichlorohydrin, the reaction can be carried out in a polar organic solvent such as dimethylformamide, dimethylacetamide, dimethyl sulfoxide, etc. at a reaction temperature of 50 to 120° C. in the presence of an alkali metal hydroxide. When the reaction temperature is within the above range, the reaction will not be too slow and side reactions can be suppressed.

[0060] As the bisphenol A type epoxy resin or bisphenol F type epoxy resin represented by formula (III'), for example, jER807, jER815, jER825, jER827, jER828, jER834, jER1001, jER1004, jER1007 and jER1009 (above are manufactured by Mitsubishi Chemical Corporation, trade names), DER-330, DER-301 and DER-361 (above are manufactured by The Dow Chemical Company, trade names), YD-8125, YDF-170, YDF-175S, YDF-2001, YDF-2004 and YDF-8170 (above are manufactured by NIPPON STEEL Chemical & Material Co., Ltd., trade names) can be commercially obtained.

[0061] (Ethylenically unsaturated group-containing organic acid (b))

[0062] As the component (b), for example, acrylic acid; acrylic acid derivatives such as acrylic acid dimer, methacrylic acid, β-furfuryl acrylic acid, β-styryl acrylic acid, cinnamic acid, crotonic acid, α-cyanocinnamic acid; half ester compounds which are reaction products of hydroxyl-containing acrylic acid ester and dibasic acid anhydride; and half ester compounds which are reaction products of vinyl-containing monoglycidyl ether or vinyl-containing monoglycidyl ester and dibasic acid anhydride. The component (b) can be used alone or in combination of two or more.

[0063] The half ester compound is obtained, for example, by reacting a hydroxyl group-containing acrylic acid ester, a vinyl group-containing monoglycidyl ether, or a vinyl group-containing monoglycidyl ester with a dibasic acid anhydride in an equimolar ratio.

[0064] Examples of the hydroxyl-containing acrylate, vinyl-containing monoglycidyl ether, and vinyl-containing monoglycidyl ester include hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, hydroxybutyl methacrylate, polyethylene glycol monoacrylate, polyethylene glycol monomethacrylate, trimethylolpropane diacrylate, trimethylolpropane dimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, dipentaerythritol pentaacrylate, pentaerythritol pentamethacrylate, glycidyl acrylate, and glycidyl methacrylate.

[0065] Examples of the dibasic acid anhydride include succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride, and itaconic anhydride.

[0066] In the reaction of component (a) and component (b), component (b) may be reacted at a ratio of 0.6 to 1.05 equivalents, or 0.8 to 1.0 equivalents, relative to 1 equivalent of the epoxy group of component (a). By reacting at such a ratio, photopolymerization can be improved, that is, photosensitivity becomes greater, and thus it is easy to improve resolution.

[0067] Component (a) and component (b) can be dissolved in an organic solvent and reacted. Examples of the organic solvent include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; glycol ethers such as methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; esters such as ethyl acetate, butyl acetate, butyl cellosolve acetate, and carbitol acetate; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, naphtha, hydrogenated naphtha, and solvent naphtha. The organic solvent may be used alone or in combination of two or more.

[0068] In order to promote the reaction of component (a) and component (b), a catalyst can be used. As the catalyst, for example, triethylamine, benzylmethylamine, methyltriethylammonium chloride, benzyltrimethylammonium chloride, benzyltrimethylammonium bromide, benzyltrimethylammonium iodide and triphenylphosphine can be mentioned. The catalyst can be used alone or in combination of two or more.

[0069] From the viewpoint of promoting the reaction between components (a) and (b), the catalyst may be used in an amount of 0.01 to 10 parts by mass, 0.05 to 2 parts by mass, or 0.1 to 1 part by mass based on 100 parts by mass of the total of components (a) and (b).

[0070] In order to prevent polymerization during the reaction, a polymerization inhibitor can be used. As the polymerization inhibitor, for example, hydroquinone, methyl hydroquinone, hydroquinone monomethyl ether, catechol and pyrogallol can be mentioned. The polymerization inhibitor can be used alone or in combination of two or more. From the viewpoint of storage stability, the amount of the polymerization inhibitor used can be 0.01 to 1 part by mass, 0.02 to 0.8 part by mass or 0.04 to 0.5 part by mass relative to 100 parts by mass of the total of components (a) and (b).

[0071] The reaction temperature of the components (a) and (b) may be 60 to 150°C, 80 to 120°C, or 90 to 110°C from the viewpoint of productivity.

[0072] It is speculated that the component (A') obtained by reacting the components (a) and (b) has a hydroxyl group formed by a ring-opening addition reaction between the epoxy group of the component (a) and the carboxyl group of the component (b). It is speculated that by further reacting the component (c) with the component (A'), an acid-modified vinyl-containing epoxy resin in which the hydroxyl group of the component (A') (including the hydroxyl group originally present in the component (a)) and the acid anhydride group of the component (c) are half-esterified can be obtained.

[0073] (Polyacid anhydride (c))

[0074] As the component (c), for example, succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride and itaconic anhydride can be mentioned. Among them, from the viewpoint of resolution, tetrahydrophthalic anhydride can be used. The component (c) can be used alone or in combination of two or more.

[0075] The reaction temperature of the component (A') and the component (c) may be 50 to 150°C, 60 to 120°C, or 70 to 100°C from the viewpoint of productivity.

[0076] If necessary, as the component (a), for example, a hydrogenated bisphenol A epoxy resin may be used in combination, or a styrene-maleic acid resin such as a hydroxyethyl (meth)acrylate-modified styrene-maleic anhydride copolymer may be used in combination.

[0077] In the reaction between the components (A') and (c), for example, the acid value of the component (A) can be adjusted by reacting the component (c) in an amount of 0.1 to 1.0 equivalents per 1 equivalent of hydroxyl groups in the component (A').

[0078] The acid value of component (A) may be 30 to 150 mgKOH / g or 40 to 120 mgKOH / g. If the acid value of component (A) is 30 mgKOH / g or more, the photosensitive resin composition tends to have excellent solubility in a dilute alkaline solution. From the same viewpoint, the acid value of component (A) may be 35 mgKOH / g or more or 40 mgKOH / g or more. If the acid value of component (A) is 150 mgKOH / g or less, it is easy to improve the electrical properties of the permanent resist. From the same viewpoint, the acid value of component (A) may be 120 mgKOH / g or less, 100 mgKOH / g or less, 90 mgKOH / g or less, 80 mgKOH / g or less, 70 mgKOH / g or less, 60 mgKOH / g or less, or 50 mgKOH / g or less.

[0079] Here, the acid value can be measured by the following method. First, accurately weigh about 1 g of the solution of component (A). Then, add 30 g of acetone to the solution and mix evenly. Add an appropriate amount of indicator phenolphthalein to the mixed solution. Titrate with 0.1N KOH aqueous solution. Calculate the titration amount of KOH aqueous solution and calculate the acid value by the following formula.

[0080] Acid value = 10 × Vf × 56.1 / (Wp × I)

[0081] In the formula, Vf represents the titration amount (mL) of 0.1N KOH aqueous solution, Wp represents the mass (g) of the solution of component (A) measured, and I represents the ratio (mass %) of the nonvolatile component in the solution of component (A) measured.

[0082] From the viewpoint of resolution, heat resistance and electrical insulation, the weight average molecular weight (Mw) of component (A) can be 3000 to 30000, 4000 to 25000 or 5000 to 18000. Here, Mw can be measured by gel permeation chromatography (GPC). Mw is measured, for example, under the following GPC conditions, and the value converted using the calibration curve of standard polystyrene can be set to Mw. The preparation of the calibration curve can use 5 sample groups ("PStQuick MP-H" and "PStQuick B", manufactured by Tosoh Corporation) as standard polystyrene.

[0083] (GPC conditions)

[0084] GPC device: High-speed GPC device "HCL-8320GPC" (manufactured by Tosoh Corporation)

[0085] Detector: Differential refractometer or UV detector (manufactured by Tosoh Corporation)

[0086] Column: Column TSKgel SuperMultipore HZH (column length: 15 cm, column inner diameter: 4.6 mm) (manufactured by Tosoh Corporation)

[0087] Eluent: Tetrahydrofuran (THF)

[0088] Measuring temperature: 40℃ Flow rate: 0.35mL / min

[0089] Sample concentration: 10mg / THF5mL

[0090] Injection volume: 20 μL

[0091] From the viewpoint of improving the heat resistance, electrical properties and chemical resistance of the permanent resist, the content of the component (A) in the photosensitive resin composition may be 10% by mass or more, 15% by mass or more, or 20% by mass or more, or 80% by mass or less, 70% by mass or less, 50% by mass or less, or 40% by mass or less, based on the total solid content of the photosensitive resin composition. From the same viewpoint, the content of the component (A) may be 10% by mass to 80% by mass, 15% by mass to 70% by mass, 20% by mass to 50% by mass, or 20% by mass to 40% by mass.

[0092] When the components (A1) and (A2) are used in combination as the component (A), from the viewpoint of improving solder heat resistance, the total content of the components (A1) and (A2) in the component (A) may be 80 to 100 mass %, 90 to 100 mass %, 95 to 100 mass % or 100 mass %, based on the total amount of the component (A). Even when the components (A1) or (A2) are used alone, they may be appropriately selected from the above ranges.

[0093] When the components (A1) and (A2) are used in combination as the component (A), the mass ratio (A1 / A2) may be 20 / 80 to 90 / 10, 20 / 80 to 80 / 20, or 30 / 70 to 70 / 30 from the viewpoint of improving solder heat resistance.

[0094] <Component (B): Epoxy compound>

[0095] The photosensitive resin composition of the present embodiment contains an epoxy compound as the (B) component. As the (B) component, an epoxy compound having two or more epoxy groups can be used, and an epoxy compound cured by heat or ultraviolet light with the carboxyl group contained in the (A) component can be cited. The photosensitive resin composition of the present embodiment can form a permanent resist having excellent heat resistance, adhesion and chemical resistance by using the (B) component. The (B) component can be used alone or in combination of two or more.

[0096] Examples of the component (B) include bisphenol A epoxy resins, bisphenol F epoxy resins, hydrogenated bisphenol A epoxy resins, brominated bisphenol A epoxy resins, novolac epoxy resins, bisphenol S epoxy resins, biphenyl epoxy resins, heterocyclic epoxy resins such as triglycidyl isocyanurate, and bixylenol epoxy resins.

[0097] From the viewpoint of crack resistance, the epoxy equivalent of the component (B) may be 100 g / eq or more, 130 g / eq or more, or 150 g / eq or more. The epoxy equivalent of the component (B) may be 450 g / eq or less, 400 g / eq or less, or 380 g / eq or less. The epoxy equivalent of the component (B) may be 100 g / eq to 450 g / eq, 130 g / eq to 400 g / eq, or 150 g / eq to 380 g / eq. The epoxy equivalent can be measured according to JIS K 7236.

[0098] From the viewpoint of crack resistance, the content of the component (B) in the photosensitive resin composition may be 2% by mass or more, 4% by mass or more, or 6% by mass or more, based on the total solid content of the photosensitive resin composition. The content of the component (B) may be 40% by mass or less, or 35% by mass or less. The content of the component (B) may be 2-40% by mass, 4-40% by mass, or 6-35% by mass.

[0099] From the viewpoint of excellent crack resistance and developability, the equivalent ratio of the epoxy group contained in the component (B) to the carboxyl group contained in the component (A) is 1.25 to 7.50. From the viewpoint of better crack resistance and developability, the equivalent ratio may be 1.50 or more, 1.75 or more, 1.95 or more, 2.00 or more, 2.20 or more, 2.40 or more, 2.50 or more, 3.00 or more, 3.50 or more, or 4.00 or more, or 7.40 or less, 7.30 or less, 7.20 or less, 7.10 or less, 7.00 or less, 6.75 or less, 6.50 or less, or 6.00 or less. From the same viewpoint, the equivalent ratio may be 2.00 to 7.50, 2.00 to 7.00, 2.50 to 7.00, or 4.00 to 7.00. When the equivalent ratio is 1.25 or more and 7.50 or less, the film tends to be excellent in resolution, solder heat resistance, solvent resistance, acid resistance, alkali resistance, and electrical insulation in addition to crack resistance and developability. That is, regarding the content of the component (B) in the photosensitive resin composition, the epoxy group contained in the component (B) is 1.25 to 7.50 equivalents relative to 1 equivalent of the carboxyl group contained in the component (A), but may be 1.50 equivalents or more, 1.75 equivalents or more, 1.95 equivalents or more, 2.00 equivalents or more, 2.20 equivalents or more, 2.40 equivalents or more, 2.50 equivalents or more, 3.00 equivalents or more, 3.50 equivalents or more, or 4.00 equivalents or less, or 7.40 equivalents or less, 7.30 equivalents or less, 7.20 equivalents or less, 7.10 equivalents or less, 7.00 equivalents or less, 6.75 equivalents or less, 6.50 equivalents or less, or 6.00 equivalents or less.

[0100] The equivalent ratio of epoxy group / carboxyl group can be calculated by the following formula.

[0101] Amount of carboxyl groups (mmol) = Number of components (A) × Acid value of component (A) (mgKOH / g) / KOH molecular weight

[0102] Epoxy group amount (mmol) = number of components (B) / epoxy equivalent weight of component (B) (g / eq) × 1000

[0103] Equivalent ratio of epoxy group / carboxyl group (molar ratio) = amount of epoxy group (mmol) / amount of carboxyl group (mmol)

[0104] <Component (C): Photopolymerization initiator>

[0105] The photosensitive resin composition of the present embodiment contains a photopolymerization initiator as the component (C). As the component (C), it is not particularly limited as long as it can polymerize the photopolymerizable compound as the component (D). As the component (C), for example, alkyl phenone-based photopolymerization initiators, acylphosphine oxide-based photopolymerization initiators, compounds having a thioxanthone skeleton, and titanocene-based photopolymerization initiators can be cited. Among them, from the viewpoint of improving the heat resistance of the solder, it can be an alkyl phenone-based photopolymerization initiator, a compound having a thioxanthone skeleton, or an acylphosphine oxide-based photopolymerization initiator. The component (C) can be used alone or in combination of two or more.

[0106] Examples of the alkylphenone-based photopolymerization initiator include benzophenone, N,N,N',N'-tetraalkyl-4,4'-diaminobenzophenone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, 4,4'-bis(dimethylamino)benzophenone (Michler's ketone), 4,4'-bis(diethylamino)benzophenone, and 4-methoxy-4'-dimethylaminobenzophenone.

[0107] Examples of the acylphosphine oxide-based photopolymerization initiator include (2,6-dimethoxybenzoyl)-2,4,4-pentylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, ethyl 2,4,6-trimethylbenzoylphenylphosphonate, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, (2,5-dihydroxyphenyl)diphenylphosphine oxide, (p-hydroxyphenyl)diphenylphosphine oxide, bis(p-hydroxyphenyl)phenylphosphine oxide, tris(p-hydroxyphenyl)phosphine oxide, and bis(2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphine oxide.

[0108] Examples of the compound having a thioxanthone skeleton include thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, isopropylthioxanthone, 2,4-diisopropylthioxanthone, and dodecylthioxanthone.

[0109] The content of the component (C) in the photosensitive resin composition is not particularly limited, but can be 0.2 to 15% by mass, 0.4 to 5% by mass, or 0.6 to 1% by mass based on the total solid content of the photosensitive resin composition. If the content of the component (C) is 0.2% by mass or more, the exposed part is difficult to dissolve during development, and if it is 15% by mass or less, it is easy to suppress the reduction of heat resistance.

[0110] <Component (D): Photopolymerizable compound>

[0111] The photosensitive resin composition of the present embodiment contains a photopolymerizable compound as the component (D). The component (D) is not particularly limited as long as it is a compound having a functional group showing photopolymerization. As the functional group showing photopolymerization, for example, ethylenically unsaturated groups such as vinyl, allyl, propargyl, butenyl, ethynyl, phenylethynyl, maleimide, nadicimide, and (meth)acryloyl can be cited. From the viewpoint of reactivity, the component (D) can contain a compound having a (meth)acryloyl group.

[0112] Examples of the component (D) include hydroxyalkyl (meth)acrylate compounds such as 2-hydroxyethyl (meth)acrylate and 2-hydroxypropyl (meth)acrylate; mono- or di-(meth)acrylate compounds of glycols such as ethylene glycol, methoxytetraethylene glycol, and polyethylene glycol; (meth)acrylamide compounds such as N,N-dimethyl (meth)acrylamide and N-hydroxymethyl (meth)acrylamide; aminoalkyl (meth)acrylate compounds such as N,N-dimethylaminoethyl (meth)acrylate; hexanediol, trimethylolpropane, pentaerythritol, ditrimethylolpropane, and the like. Poly (meth)acrylate compounds of polyols such as methylolpropane, dipentaerythritol, tris-hydroxyethyl isocyanurate or their ethylene oxide or propylene oxide adducts; (meth)acrylate compounds of ethylene oxide or propylene oxide adducts of phenol compounds such as phenoxyethyl (meth)acrylate and polyethoxy di(meth)acrylate of bisphenol A; (meth)acrylate compounds of glycidyl ethers such as glycerol diglycidyl ether, trimethylolpropane triglycidyl ether, and isocyanuric acid triglycidyl ether; and melamine (meth)acrylate. Component (D) can be used alone or in combination of two or more.

[0113] The content of the component (D) in the photosensitive resin composition may be 0.1 to 10% by mass, 0.5 to 8% by mass, or 2 to 7% by mass, based on the total solid content in the photosensitive resin composition. If the content of the component (D) is 0.1% by mass or more, the exposed portion is difficult to dissolve during development, and if it is 10% by mass or less, the heat resistance is easily improved.

[0114] <(E) Ingredient: Pigment>

[0115] The photosensitive resin composition of the present embodiment may further contain a pigment as the component (E). As the component (E), a colorant that develops a desired color when hiding wiring, etc. can be used. As the component (E), for example, known colorants such as phthalocyanine blue, phthalocyanine green, iodine green, diazo yellow, crystal violet, titanium oxide, carbon black, and naphthalene black can be cited. The component (E) can be used alone or in combination of two or more.

[0116] From the viewpoint of further concealing wiring, the content of the component (E) may be 2 to 30% by mass, 2.5 to 20% by mass, or 2.5 to 10% by mass based on the total solid content in the photosensitive resin composition.

[0117] <(F) ingredient: inorganic filler>

[0118] In order to improve the adhesion and hardness of the permanent resist, the photosensitive resin composition of the present embodiment contains an inorganic filler as the (F) component. As the (F) component, for example, silica, alumina, zirconium oxide, talc, aluminum hydroxide, calcium carbonate, barium sulfate, calcium sulfate, zinc oxide, magnesium titanate and carbon can be cited. The (F) component can be used alone or in combination of two or more.

[0119] From the viewpoint of crack resistance, developability and resolution, the component (F) contains a silica filler having a vinyl group derived from a vinyl silane compound (hereinafter sometimes referred to as a "vinyl-containing silica filler"). The vinyl-containing silica filler can be obtained by surface-treating silica particles with a vinyl silane compound. The surface treatment can be performed, for example, by adding a solution of a vinyl silane compound to the silica particles and stirring.

[0120] The vinyl silane compound is not particularly limited as long as it is a silane compound having one or more vinyl groups bonded to a silicon atom. In the vinyl silane compound, the number of vinyl groups bonded to a silicon atom may be 2 or 3. As a group other than the vinyl group bonded to a silicon atom, the vinyl silane compound may have an alkoxy group, an acetoxy group, an alkyl group, etc. As the vinyl silane compound, for example, vinyl alkoxysilane and acetoxysilane in which the alkoxy group in the vinyl alkoxysilane is substituted by an acetoxy group can be cited.

[0121] Vinylalkoxysilane is not particularly limited as long as it is a silane compound having a vinyl group bonded to a silicon atom and an alkoxy group bonded to a silicon atom. In vinylalkoxysilane, the number of alkoxy groups bonded to a silicon atom may be 2 or 3. In vinylalkoxysilane, when the number of alkoxy groups bonded to a silicon atom is 2 or more, these alkoxy groups may be the same as or different from each other. The number of carbon atoms of the alkoxy group bonded to a silicon atom may be 1 to 10, 1 to 6, 1 to 5, 1 to 4 or 1 to 3. Vinylalkoxysilane may have an alkyl group bonded to a silicon atom. When vinylalkoxysilane has an alkyl group bonded to a silicon atom, the number of carbon atoms of the alkyl group may be 1 to 10, 1 to 6, 1 to 5, 1 to 4 or 1 to 3.

[0122] As the vinyl alkoxysilane, for example, vinyl trialkoxysilanes having three alkoxy groups bonded to silicon atoms, such as vinyl trimethoxysilane, vinyl triethoxysilane, and vinyl triisopropoxysilane, vinyl dialkoxysilanes having two alkoxy groups bonded to silicon atoms, such as vinyl dimethoxysilane, vinyl diethoxysilane, and vinyl diisopropoxysilane, and vinyl alkoxysilanes having one alkoxy group bonded to silicon atoms, such as vinyl monomethoxysilane, vinyl monoethoxysilane, and vinyl monoisopropoxysilane, can be cited. These vinyl alkoxysilanes can be used alone or in combination of two or more.

[0123] Examples of the vinyl acetoxysilane include vinyl triacetoxysilane, vinyl diacetoxysilane, and vinyl monoacetoxysilane.

[0124] From the viewpoint of solder heat resistance, crack resistance and pressure cooker resistance (PCT resistance), the component (F) may contain barium sulfate. From the viewpoint of improving the anti-agglomeration effect, the component (F) may contain aluminum oxide.

[0125] The average particle size of the component (F) may be 0.1 to 20 μm, 0.1 to 10 μm, 0.1 to 5 μm, or 0.1 to 1 μm. When the average particle size is 20 μm or less, a decrease in the insulation reliability of the permanent resist can be further suppressed.

[0126] Based on the total solid content of the photosensitive resin composition, the content of the (F) component can be 10 to 80% by mass, 15 to 70% by mass, 20 to 60% by mass, 25 to 50% by mass, or 30 to 45% by mass. If the content of the (F) component is within the above range, the resolution of the photosensitive resin composition can be further improved, and the strength, heat resistance, insulation reliability, and crack resistance of the permanent resist can be further improved. From the same point of view, the content of the (F) component can be 10% by mass or more, 15% by mass or more, 20% by mass or more, 25% by mass or more, or 30% by mass or less, or 80% by mass or less, 70% by mass or less, 60% by mass or less, 50% by mass or less, or 45% by mass or less.

[0127] Based on the total solid content of the photosensitive resin composition, the content of the vinyl-containing silica filler can be 5-60 mass%, 15-55 mass%, 20-50 mass% or 25-45 mass%. If the content of the vinyl-containing silica filler is within the above range, the developability and resolution of the photosensitive resin composition and the crack resistance of the permanent resist can be further improved. From the same point of view, the content of the vinyl-containing silica filler can be 5 mass% or more, 15 mass% or more, 20 mass% or more or 25 mass% or more, and can also be 60 mass% or less, 55 mass% or less, 50 mass% or less or 45 mass% or less.

[0128] From the viewpoint of developability, resolution and crack resistance, the content of the vinyl-containing silica filler in the component (F) may be 50% to 100% by mass, 55% to 100% by mass, 60% to 100% by mass or 65% to 100% by mass, based on the total amount of the component (F).

[0129] When barium sulfate is used as the component (F), the content of barium sulfate can be 5 to 30 mass %, 5 to 25 mass %, or 5 to 20 mass % based on the total solid content of the photosensitive resin composition. If the content of barium sulfate is within the above range, solder heat resistance and PCT resistance can be further improved.

[0130] <Component (G): Curing agent>

[0131] The photosensitive resin composition of this embodiment may further include a curing agent as component (G). As component (G), for example, a compound that is cured by heat, ultraviolet rays, etc., or a compound that is cured by heat, ultraviolet rays, etc., and reacts with a carboxyl group or a hydroxyl group of component (A) to form a solid. By using a curing agent, the heat resistance, adhesion, chemical resistance, etc. of the permanent resist can be improved.

[0132] As the component (G), for example, thermosetting compounds such as melamine compounds and oxazoline compounds can be cited. As the melamine compound, for example, triaminotriazine, hexamethoxymelamine and hexabutoxylated melamine can be cited. The component (G) can be used alone or in combination of two or more.

[0133] When the component (G) is used, its content can be 2-40 mass %, 3-30 mass % or 5-20 mass % based on the total solid content of the photosensitive resin composition. If the content of the component (G) is within the above range, better developability can be maintained and the heat resistance of the permanent resist formed can be further improved.

[0134] In order to further improve the properties of the permanent resist, such as heat resistance, adhesion, and chemical resistance, the photosensitive resin composition of the present embodiment may be used together with a curing accelerator for accelerating the curing of the component (D).

[0135] Examples of curing accelerators include imidazole derivatives such as 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 2-phenylimidazole, and 2-phenyl-4-methyl-5-hydroxymethylimidazole; guanamines such as acetoguanamine and benzoguanamine; polyamines such as diaminodiphenylmethane, metaphenylenediamine, metaxylenediamine, diaminodiphenylsulfone, dicyandiamide, urea, urea derivatives, melamine, and polyhydrazides; organic acid salts or epoxy adducts thereof; amine complexes of boron trifluoride; triazine derivatives such as ethyldiamino-s-triazine, 2,4-diamino-s-triazine, and 2,4-diamino-6-xylyl-s-triazine. The curing accelerators can be used alone or in combination of two or more.

[0136] When a curing accelerator is used, the content thereof may be 0.01 to 20% by mass or 0.1 to 10% by mass based on the total solid content of the photosensitive resin composition from the viewpoint of improving reliability.

[0137] <(H) Component: Elastomer>

[0138] The photosensitive resin composition of the present embodiment may also contain an elastomer as the (H) component. The (H) component may also be used when the photosensitive resin composition of the present embodiment is used for a semiconductor package substrate. By adding the (H) component to the photosensitive resin composition, the reduction in flexibility and adhesive strength caused by the deformation (internal stress) inside the resin caused by the curing shrinkage of the (A) component can be suppressed. That is, the flexibility and adhesive strength of the permanent resist formed by the photosensitive resin composition can be improved.

[0139] As the component (H), for example, thermoplastic elastomers such as styrene elastomers, olefin elastomers, urethane elastomers, polyester elastomers, polyamide elastomers, acrylic elastomers, silicone elastomers, etc. can be cited. Thermoplastic elastomers are composed of a hard segment component that contributes to heat resistance and strength and a soft segment component that contributes to flexibility and toughness. The component (H) can be used alone or in combination of two or more.

[0140] As the urethane elastomer, a compound composed of a hard segment formed of a low molecular (short chain) diol and a diisocyanate and a soft segment formed of a high molecular (long chain) diol and a diisocyanate can be used. As the low molecular diol, for example, ethylene glycol, propylene glycol, 1,4-butanediol and bisphenol A can be mentioned. As the high molecular diol, for example, polypropylene glycol, polytetramethylene oxide, poly(1,4-butylene adipate), poly(ethylene-1,4-butylene adipate), polycaprolactone, poly(1,6-hexylene carbonate) and poly(1,6-hexylene-neopentylene adipate) can be mentioned.

[0141] The number average molecular weight (Mn) of the low molecular weight diol may be 48 to 500. The Mn of the high molecular weight diol may be 500 to 10000. As the urethane elastomer, for example, PANDEX T-2185, T-2983N (manufactured by DIC Corporation) and miractran E790 (manufactured by Nippon Miractran Company Limited) are commercially available.

[0142] As the polyester elastomer, a compound obtained by polycondensing a dicarboxylic acid or a derivative thereof with a diol compound or a derivative thereof can be used. Examples of the dicarboxylic acid include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and naphthalene dicarboxylic acid, and aromatic dicarboxylic acids in which hydrogen atoms of the aromatic nucleus are substituted with methyl, ethyl, phenyl, etc.; aliphatic dicarboxylic acids having 2 to 20 carbon atoms such as adipic acid, sebacic acid, and dodecanedicarboxylic acid; and alicyclic dicarboxylic acids such as cyclohexane dicarboxylic acid.

[0143] Examples of the diol compound include aliphatic diols or alicyclic diols such as ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,10-decanediol, and 1,4-cyclohexanediol, and dihydric phenols represented by the following formula (IV).

[0144]

[0145] In formula (IV), Y represents an alkylene group having 1 to 10 carbon atoms, a cycloalkylene group having 4 to 8 carbon atoms, an ether group, a thioether group, a sulfonyl group or a single bond, and R 1 and R2 Each independently represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 12 carbon atoms, l and m each independently represent an integer of 0 to 4, and p is 0 or 1. The alkylene group and the cycloalkylene group may be linear or branched, and may be substituted with a halogen atom, an alkyl group, an aryl group, an aralkyl group, an amino group, an amide group, an alkoxy group, or the like.

[0146] Examples of the dihydric phenol represented by formula (IV) include bisphenol A, bis(4-hydroxyphenyl)methane, bis(4-hydroxy-3-methylphenyl)propane, and resorcinol. These compounds can be used alone or in combination of two or more.

[0147] As the polyester elastomer, a multi-block copolymer having an aromatic polyester (e.g., polybutylene terephthalate) portion as a hard segment component and an aliphatic polyester (e.g., polytetramethylene glycol) portion as a soft segment component can be used. There are different grades of polyester elastomers depending on the type, ratio, and molecular weight of the hard segment and the soft segment. As the polyester elastomer, for example, Hytrel (manufactured by DU PONT-TORAY CO., LTD., "Hytrel" is a registered trademark), PELPRENE (manufactured by TOYOBO CO., LTD., "PELPRENE" is a registered trademark), and Espel (manufactured by Showa Denko Materialsco., Ltd., "Espel" is a registered trademark) can be commercially obtained.

[0148] Acrylic elastomers can use compounds containing acrylate-based structural units as main components. Examples of acrylate include ethyl acrylate, butyl acrylate, methoxyethyl acrylate, and ethoxyethyl acrylate. Acrylic elastomers can be compounds obtained by copolymerizing acrylate and acrylonitrile, or compounds obtained by further copolymerizing monomers having functional groups that serve as crosslinking points. Examples of monomers having functional groups include glycidyl methacrylate and allyl glycidyl ether. Examples of acrylic elastomers include acrylonitrile-butyl acrylate copolymers, acrylonitrile-butyl acrylate-ethyl acrylate copolymers, and acrylonitrile-butyl acrylate-glycidyl methacrylate copolymers.

[0149] As an elastomer other than thermoplastic elastomer, a rubber-modified epoxy resin can be used. The rubber-modified epoxy resin can be obtained, for example, by the following method: using a butadiene-acrylonitrile rubber modified with carboxylic acids at both ends, a silicone rubber modified with amino groups at the end, etc., to modify part or all of the epoxy groups possessed by the above-mentioned bisphenol F epoxy resin, bisphenol A epoxy resin, salicylaldehyde epoxy resin, phenol novolac epoxy resin or cresol novolac epoxy resin. Among these elastomers, from the viewpoint of shear adhesion, a butadiene-acrylonitrile copolymer modified with carboxyl groups at both ends and Espel (manufactured by Showa Denko Materials Co., Ltd., Espel1612, 1620) as a polyester elastomer having a hydroxyl group can be used.

[0150] The content of the component (H) may be 2 to 40 parts by mass, 4 to 30 parts by mass, 10 to 25 parts by mass, or 15 to 22 parts by mass relative to 100 parts by mass of the component (A). By setting the content of the component (H) within the above range, the unexposed portion of the photosensitive layer is more easily dissolved in the developer, and there is a tendency that the elastic modulus of the permanent resist in a high temperature region is further reduced.

[0151] <Other ingredients>

[0152] In the photosensitive resin composition of this embodiment, a diluent such as an organic solvent may be mixed as needed to adjust the viscosity. Examples of the organic solvent include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; glycol ethers such as methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; esters such as ethyl acetate, butyl acetate, butyl cellosolve acetate, and carbitol acetate; aliphatic hydrocarbons such as octane and decane; and petroleum-based solvents such as petroleum ether, naphtha, hydrogenated naphtha, and solvent naphtha.

[0153] When a diluent is used, the content of the diluent in the photosensitive resin composition may be 10 to 50 mass %, 20 to 40 mass %, or 25 to 35 mass %. By setting the content of the diluent within the above range, the coating properties of the photosensitive resin composition can be improved, and a higher-definition pattern can be formed.

[0154] In the photosensitive resin composition of this embodiment, various additives may be mixed as needed. Examples of the additives include polymerization inhibitors such as hydroquinone, methyl hydroquinone, hydroquinone monomethyl ether, catechol, and pyrogallol; thickeners such as organic clay and montmorillonite; silicone-based, fluorine-based, or vinyl resin-based defoamers; silane coupling agents; and flame retardants such as brominated epoxy compounds, acid-modified brominated epoxy compounds, antimony compounds, phosphate compounds of phosphorus compounds, aromatic condensed phosphate esters, and halogen-containing condensed phosphate esters.

[0155] The photosensitive resin composition of the present embodiment can be prepared by uniformly mixing the above-mentioned components using a roll mill, a bead mill, or the like.

[0156] [Photosensitive element]

[0157] The photosensitive element of the present embodiment includes a support film and a photosensitive layer containing the above-mentioned photosensitive resin composition. Figure 1 2 is a cross-sectional view schematically showing a photosensitive element according to this embodiment. Figure 1 As shown, the photosensitive element 1 includes a support film 10 and a photosensitive layer 20 formed on the support film 10 .

[0158] The photosensitive element 1 can be produced by, for example, applying the photosensitive resin composition of the present embodiment on the support film 10 by a known method such as reverse roll coating, gravure roll coating, comma coating, curtain coating, and then drying the coated film to form the photosensitive layer 20 .

[0159] Examples of the support film include polyester films such as polyethylene terephthalate and polybutylene terephthalate, and polyolefin films such as polypropylene and polyethylene. The thickness of the support film may be, for example, 5 to 100 μm. The thickness of the photosensitive layer may be, for example, 10 to 50 μm, 15 to 40 μm, or 20 to 30 μm.

[0160] The coating film can be dried by hot air drying, far infrared ray drying or near infrared ray drying. The drying temperature may be 60 to 120° C., 70 to 110° C. or 80 to 100° C. The drying time may be 1 to 60 minutes, 2 to 30 minutes or 5 to 20 minutes.

[0161] A protective film 30 covering the photosensitive layer 20 may be further provided on the photosensitive layer 20. The photosensitive element 1 may also be laminated with the protective film 30 on the surface of the photosensitive layer 20 opposite to the surface in contact with the support film 10. As the protective film 30, for example, a polymer film such as polyethylene or polypropylene may be used. The protective film may be the same film as the support film or a different film therefrom.

[0162] [Printed circuit board]

[0163] The printed wiring board of this embodiment includes a permanent resist containing a cured product of the photosensitive resin composition of this embodiment. The printed wiring board of this embodiment includes a permanent resist containing a cured product of the photosensitive resin composition of this embodiment, and thus the occurrence of cracks in the permanent resist can be reduced.

[0164] The method for manufacturing a printed wiring board of the present embodiment comprises: forming a photosensitive layer on a substrate using the photosensitive resin composition or the photosensitive element, exposing and developing the photosensitive layer to form a resist pattern, and curing the resist pattern to form a permanent resist. An example of each step is described below.

[0165] First, as a substrate, a metal-clad laminate such as a copper-clad laminate is prepared, and a photosensitive layer is formed on the substrate. When a photosensitive resin composition is used, the photosensitive resin composition can also be applied to the substrate by screen printing, spraying, roller coating, curtain coating, electrostatic coating, etc., and the formed coating film is dried at 60 to 110° C. to form a photosensitive layer. The thickness of the coating film can be 10 to 200 μm, 15 to 150 μm, 20 to 100 μm, or 23 to 50 μm. When a photosensitive element is used, the photosensitive layer of the photosensitive element can also be thermally laminated to the substrate using a laminator to form a photosensitive layer.

[0166] Next, the negative mask is brought into direct contact with the photosensitive layer or into contact with the photosensitive layer via a transparent film such as a support film, and after exposure to active light, the unexposed portion is dissolved and removed with a developer to form a resist pattern. As active light, for example, electron beams, ultraviolet rays, X-rays, etc. can be cited, preferably ultraviolet rays. As a light source, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a halogen lamp, etc. can be used. The exposure amount can be 10 to 2000 mJ / cm 2 100~1500mJ / cm 2 or 300~1000mJ / cm 2 As a developing method, for example, an immersion method and a spray method can be mentioned. As a developing solution, for example, an alkaline aqueous solution such as potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, tetramethylammonium hydroxide, etc. can be used.

[0167] Next, the formed resist pattern can be subjected to at least one of post-exposure and post-heating to fully cure the resist pattern to form a permanent resist. The exposure dose of the post-exposure can be 100 to 5000 mJ / cm 2 , 500~2000mJ / cm 2 or 700~1500mJ / cm 2The heating temperature of the post-heating may be 100 to 200° C., 120 to 180° C., or 135 to 165° C. The heating time of the post-heating may be 5 minutes to 12 hours, 10 minutes to 6 hours, or 30 minutes to 2 hours. The thickness of the permanent resist may be 10 to 50 μm, 15 to 40 μm, or 20 to 30 μm. Afterwards, a circuit is formed by etching to produce a printed circuit board.

[0168] The permanent resist of the present embodiment can be used as an interlayer insulating layer or a surface protective layer of a semiconductor element. A semiconductor element having an interlayer insulating layer or a surface protective layer formed by a cured film of the above-mentioned photosensitive resin composition, and an electronic device comprising the semiconductor element can be produced. The semiconductor element can be, for example, a memory (memory), a package, etc. having a multilayer wiring structure, a redistribution structure, etc. As an electronic device, for example, a mobile phone, a smart phone, a tablet terminal, a personal computer, and a hard disk suspension can be cited. By having a patterned cured film formed by the photosensitive resin composition of the present embodiment, a semiconductor element and an electronic device with excellent reliability can be provided.

[0169] Example

[0170] Hereinafter, the present invention will be described in further detail with reference to Examples, but the present invention is not limited to these Examples.

[0171] (Synthesis example 1)

[0172] A bisphenol F novolac epoxy resin (trade name: EXA-7376; manufactured by DIC Corporation; having Y in formula (I)) was placed in a flask equipped with a stirrer, a reflux condenser, and a thermometer. 1 and Y 2 is a glycidyl group, R 11 350 parts by mass of a bisphenol F novolac epoxy resin having a structure of hydrogen atoms; epoxy equivalent: 186 g / eq), 70 parts by mass of acrylic acid, 0.5 parts by mass of methyl hydroquinone and 120 parts by mass of carbitol acetate were added, and stirred at 90°C to completely dissolve the mixture. Then, the obtained solution was cooled to 60°C, 2 parts by mass of triphenylphosphine was added, and heated to 100°C to react until the acid value of the solution reached 1 mgKOH / g or less. 98 parts by mass of tetrahydrophthalic anhydride (THPAC) and 85 parts by mass of carbitol acetate were added to the reacted solution, and reacted at 80°C for 6 hours. Then, it was cooled to room temperature to obtain a solution of THPAC-modified bisphenol F novolac epoxy acrylate as component (A) (solid content acid value: 50.0 mgKOH / g; solid content concentration: 73% by mass).

[0173] [Photosensitive resin composition]

[0174] Each component was mixed in the amounts shown in Tables 1 and 2 and kneaded using a three-roll mill. Carbitol acetate was then added so that the solid content concentration became 70% by mass to obtain a photosensitive resin composition. Tables 1 and 2 show the mass fractions of the solid content of the components (A) to (F) based on the total solid content of the photosensitive resin composition.

[0175] The details of each component in Table 1 and Table 2 are as follows.

[0176] A-1: Acid-modified vinyl-containing resin obtained in Synthesis Example 1

[0177] A-2: For R in formula (III') 13 is a hydrogen atom, Y 5 Acid-modified vinyl-containing resin (acid value: 42.4 mgKOH / g) obtained by acrylate-esterifying the glycidyl groups of a novolac epoxy resin having a glycidyl structure (trade name: UE-EXP-3165; manufactured by DIC Corporation) and modifying the hydroxyl groups with tetrahydrophthalic anhydride

[0178] B-1: Bisphenol A type epoxy resin (trade name: YD-8125; manufactured by NIPPON STEEL Chemical & Material Co., Ltd.; epoxy equivalent: 173 g / eq)

[0179] B-2: Novolac type multifunctional epoxy resin (trade name: RE-306; manufactured by Nippon Kayaku Co., Ltd.; epoxy equivalent: 270 g / eq)

[0180] B-3: Bisphenol A type novolac epoxy resin (trade name: jER157S70; manufactured by Mitsubishi Chemical Corporation; epoxy equivalent: 210 g / eq)

[0181] B-4: Bisphenol F type epoxy resin (trade name: EXA-9580; manufactured by DIC Corporation; epoxy equivalent: 360 g / eq)

[0182] B-5: 4-functional epoxy resin (trade name: jER1031S; manufactured by Mitsubishi Chemical Corporation; epoxy equivalent: 200 g / eq)

[0183] C-1: 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone (trade name: IRGACURE 907; manufactured by BASF)

[0184] C-2: 2,4-diethylthioxanthone (trade name: DETX-S; manufactured by Nippon Kayaku Co., Ltd.)

[0185] D-1: Dipentaerythritol hexaacrylate (trade name: DPHA; manufactured by Nippon Kayaku Co., Ltd.)

[0186] E-1: Phthalocyanine pigment (trade name: CIPigment Blue 15; manufactured by SANYO COLOR WORKS, Ltd.)

[0187] F-1: Barium sulfate particles (trade name: B34; manufactured by SAKAI CHEMICAL INDUSTRY CO., LTD.; average particle size: 0.3 μm)

[0188] F-2: A silica filler having a vinyl group derived from a vinylsilane compound obtained by adding 1 g of 1 mass % vinyltrimethoxysilane (trade name: KBM-1003; manufactured by Shin-Etsu Chemical Co., Ltd.) to 100 g of untreated silica particles (trade name: SO-C2; manufactured by ADMATECHS COMPANY LIMITED, average particle size: 0.5 μm), and stirring the mixture at 80° C. for 30 minutes.

[0189] F-3: A silica filler having an epoxy group obtained in the same manner as F-2 except that vinyl trimethoxysilane was replaced with 3-glycidyloxypropyl trimethoxysilane (trade name: KBM-403; manufactured by Shin-Etsu Chemical Co., Ltd.)

[0190] F-4: A silica filler having a methacryl group obtained in the same manner as F-2 except that vinyltrimethoxysilane was replaced with 3-methacryloxypropylmethyldimethoxysilane (trade name: KBM-502; manufactured by Shin-Etsu Chemical Co., Ltd.)

[0191] F-5: A silica filler having an aniline group obtained in the same manner as F-2 except that vinyltrimethoxysilane was replaced with N-phenyl-3-aminopropyltrimethoxysilane (trade name: KBM-573; manufactured by Shin-Etsu Chemical Co., Ltd.)

[0192] F-6: Untreated silica particles (trade name: SO-C2; manufactured by ADMATECHS COMPANY LIMITED, average particle size: 0.5 μm)

[0193] As shown below, the amount of carboxyl groups in component (A) and the amount of epoxy groups in component (B) were calculated to obtain the equivalent ratios shown in Tables 1 and 2, that is, the equivalent ratios of the epoxy groups contained in component (B) to the carboxyl groups contained in component (A).

[0194] Amount of carboxyl groups (mmol) = mass fraction of component (A) (g) × acid value of component (A) (mgKOH / g) / molecular weight of KOH

[0195] Amount of epoxy group (mmol) = mass part of component (B) (g) / epoxy equivalent of component (B) (g / eq) × 1000

[0196] Taking Example 1 as an example, the mass fraction (solid content) of component (A) is 26.9 (g), the acid value (solid content) of component (A) is 50 (mgKOH / g), and the molecular weight of KOH is 56.11, so the amount of carboxyl groups in component (A) is 26.9×50 / 56.11=23.97 (mmol). The mass fraction (solid content) of component (B) is 6.2 g, and the epoxy equivalent of component (B) is 173 g / eq, so the amount of epoxy groups in component (B) is 6.2 / 173×1000=35.84 (mmol). Therefore, in Example 1, the equivalent ratio of the epoxy groups of component (B) to the carboxyl groups of component (A) is 1.50.

[0197] The photosensitive resin composition was used to perform each evaluation under the conditions shown below. The results are shown in Tables 1 and 2.

[0198] (Preparation of Test Specimen 1)

[0199] The photosensitive resin composition of the embodiment and the comparative example was applied by screen printing on a copper-clad laminate substrate (copper-clad laminate substrate having copper foil disposed on a glass epoxy material, manufactured by Showa Denko Materials Co., Ltd., trade name: MCL-E-67) with a thickness of 0.6 mm, so that the thickness after drying reached 35 μm, and then dried at 80° C. using a hot air circulation dryer for 20 minutes to form a photosensitive layer. Next, a negative mask having a predetermined pattern was placed in close contact with the obtained photosensitive layer, and an ultraviolet exposure device was used at 600 mJ / cm 2 Afterwards, a 1 mass % sodium carbonate aqueous solution was used at 1.765×10 5The unexposed area was then subjected to spray development at a pressure of 1000 mJ / cm2 using an ultraviolet exposure device. 2 The film was exposed with an exposure amount of 1000 nm and heated at 150° C. for 1 hour to prepare a test piece 1 having a permanent resist.

[0200] (Crack resistance)

[0201] Test piece 1 was subjected to a temperature cycle test with 30 minutes at -65°C and 30 minutes at 150°C as one cycle. The permanent resist was observed visually and under an optical microscope at 1000, 2000 and 3000 cycles, and crack resistance was evaluated according to the following criteria.

[0202] S: No cracks were observed in 3000 cycles.

[0203] A: No crack generation was observed in 2000 cycles, but crack generation was observed in 3000 cycles.

[0204] B: No crack generation was observed in 1000 cycles, but crack generation was observed in 2000 cycles.

[0205] C: Generation of cracks was observed in 1000 cycles.

[0206] (Developability)

[0207] The photosensitive resin composition of the embodiment and the comparative example was applied to a copper-clad laminate substrate (manufactured by Showa Denko Materials Co., Ltd., trade name: MCL-E-67) by screen printing to a thickness of 15 μm after drying, and then dried at 75° C. using a hot air circulation dryer for 30 minutes to form a photosensitive layer. Next, the obtained photosensitive layer was irradiated with a cumulative exposure of 100 mJ / cm through a negative mask having non-transparent portions with a diameter of 80 μm scattered over an area of ​​1×1 cm square. 2 Then, a 1% sodium carbonate aqueous solution was used at 1.8 kgf / cm 2 The test piece 2 was prepared by spray development for 60 seconds at a pressure of , and the unexposed portion was dissolved and developed. Then, the opening of the test piece 2 was observed at 10,000 times using a SEM (manufactured by Hitachi High-Tech Corporation., model: S4200, field emission scanning electron microscope), and the developability was evaluated according to the following criteria based on the residual state of the resist residue.

[0208] S: There are 0 residues in one field of view.

[0209] A: There are 1 or more and less than 5 residues in one field of view.

[0210] B: There are 5 or more and less than 10 residues in one field of view.

[0211] C: There are 10 or more residues in one field of view.

[0212] (Resolution)

[0213] As a negative mask, a negative mask having an opening pattern of a predetermined size (opening diameter size: 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 150, 200 μm) was used, and a test piece 3 having a cured film formed with an opening pattern of a predetermined size was prepared in the same manner as the test piece 1. The test piece 3 was observed using an optical microscope, and the resolution was evaluated according to the following criteria.

[0214] A: The minimum diameter of the mask opening is 35 μm or less.

[0215] B: The minimum diameter of the mask diameter of the opening is more than 35 μm and is 55 μm or less.

[0216] C: The minimum diameter of the mask opening exceeds 55 μm.

[0217] (Solder heat resistance)

[0218] A water-soluble flux was applied to the test piece 1, and the test piece was immersed in a solder bath at 265°C for 10 seconds. This was considered one cycle, and after six cycles were repeated, the appearance of the permanent resist was visually observed, and the solder heat resistance was evaluated according to the following criteria.

[0219] A: There is no change in appearance within the permanent resist area of ​​30 cm x 30 cm.

[0220] B: Within 30 cm×30 cm of the permanent resist, 1 to 5 coating films were lifted or blistered.

[0221] C: 6 or more coating film lift-offs or blistering occurred within 30 cm×30 cm of the permanent resist.

[0222] (Solvent resistance)

[0223] The test piece 1 was immersed in isopropyl alcohol at room temperature for 30 minutes, and after confirming whether there was any abnormality in the appearance of the permanent resist, a peeling test was performed using a cellophane tape. The solvent resistance was evaluated according to the following criteria.

[0224] A: There was no abnormality in the appearance of the permanent resist, and no peeling occurred.

[0225] B: The appearance of the permanent resist has changed slightly.

[0226] C: The appearance of the permanent resist is abnormal or peeling occurs.

[0227] (Acid resistance)

[0228] The test piece 1 was immersed in a 10 mass % hydrochloric acid aqueous solution at room temperature for 30 minutes, and after confirming whether there was any abnormality in the appearance of the permanent resist, a peeling test was performed using a cellophane tape. The acid resistance was evaluated according to the following criteria.

[0229] A: There was no abnormality in the appearance of the permanent resist, and no peeling occurred.

[0230] B: The appearance of the permanent resist has changed slightly.

[0231] C: The appearance of the permanent resist is abnormal or peeling occurs.

[0232] (Alkali resistance)

[0233] The test piece 1 was immersed in a 5 mass % sodium hydroxide aqueous solution at room temperature for 30 minutes, and after confirming whether there was any abnormality in the appearance of the permanent resist, a peeling test was performed using a cellophane tape. Alkali resistance was evaluated according to the following criteria.

[0234] A: There was no abnormality in the appearance of the permanent resist, and no peeling occurred.

[0235] B: The appearance of the permanent resist has changed slightly.

[0236] C: The appearance of the permanent resist is abnormal or peeling occurs.

[0237] (Electrical insulation)

[0238] Test piece 4 was formed in the same manner as test piece 1 except that a bismaleimide triazine substrate formed with comb-shaped electrodes (line / space = 10 μm / 10 μm) was used instead of the copper-clad laminate substrate. Next, test piece 4 was exposed to the conditions of 135° C., 85%, and 5 V. Thereafter, the degree of migration in the permanent resist was observed with a metal microscope at 100 times magnification, and the electrical insulation was evaluated according to the following criteria.

[0239] A: Even after more than 200 hours, no migration occurred in the permanent resist and the resistance value did not drop to 10 -6 Ω or less.

[0240] B: No migration occurs in the permanent resist and the resistance value does not decrease to 10 within 100 hours or more and less than 200 hours. -6 Ω or less.

[0241] C: In less than 100 hours, migration occurs in the permanent resist and the resistance value decreases to 10 -6 Ω or less.

[0242] [Table 1]

[0243]

[0244] [Table 2]

[0245]

[0246] From Tables 1 and 2, it was confirmed that the photosensitive resin composition of the Example could form a permanent resist having excellent crack resistance and had excellent developability.

[0247] [Photosensitive element]

[0248] Each photosensitive resin composition was diluted with methyl ethyl ketone, applied on a polyethylene terephthalate (PET) film, and dried at 90° C. for 10 minutes to form a photosensitive layer having a thickness of 25 μm. A PET film was laminated on the photosensitive layer as a protective film to prepare a photosensitive element.

[0249] The photosensitive layer of the photosensitive element was used to evaluate crack resistance, developability, resolution, solder heat resistance, solvent resistance, acid resistance, alkali resistance, and electrical insulation, and the same results as those obtained when the photosensitive resin compositions shown in Tables 1 and 2 were used were obtained. The test piece when the photosensitive layer was used was prepared in the same manner as the above-mentioned test pieces 1 to 4 except that the protective film was peeled off from the above-mentioned photosensitive element, and the support film was peeled off after the photosensitive layer of the photosensitive element was thermally laminated on the substrate, thereby forming the photosensitive layer on the substrate.

[0250] Explanation of symbols

[0251] 1-photosensitive element, 10-support film, 20-photosensitive layer, 30-protective film.

Claims

1. A photosensitive resin composition for a permanent resist, comprising: (A) an acid-modified vinyl-containing resin, (B) an epoxy compound, (C) a photopolymerization initiator, (D) a photopolymerizable compound, and (F) an inorganic filler, The equivalent ratio of the epoxy groups contained in the (B) epoxy compound to the carboxyl groups contained in the (A) acid-modified vinyl-containing resin is 1.25 to 7.50, (F) The inorganic filler includes a silica filler having a vinyl group derived from a vinylsilane compound.

2. The photosensitive resin composition according to claim 1, wherein The equivalent ratio is 2.00 to 7.

50.

3. The photosensitive resin composition according to claim 1, wherein The equivalent ratio is 2.50 to 7.

50. 4 . The photosensitive resin composition according to claim 1 , further comprising (E) a pigment.

5. A photosensitive element comprising a support film and a photosensitive layer formed on the support film, The photosensitive layer contains the photosensitive resin composition according to any one of claims 1 to 4. 6 . A printed wiring board comprising a permanent resist containing a cured product of the photosensitive resin composition according to claim 1 .

7. The printed wiring board according to claim 6, wherein: The thickness of the permanent resist is 10-50 μm.

8. A method for manufacturing a printed circuit board, comprising: A step of forming a photosensitive layer on a substrate using the photosensitive resin composition according to any one of claims 1 to 4; A step of exposing and developing the photosensitive layer to form a resist pattern; and The process of curing the resist pattern to form a permanent resist.

9. A method for manufacturing a printed circuit board, comprising: A step of forming a photosensitive layer on a substrate using the photosensitive element according to claim 5; A step of exposing and developing the photosensitive layer to form a resist pattern; and The process of curing the resist pattern to form a permanent resist.

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