Photosensitive resin composition, photosensitive resin film, multilayer printed wiring board and semiconductor package, and method for manufacturing multilayer printed wiring board

Abstract

To provide a photosensitive resin composition that achieves low dielectric loss tangents and also has excellent desmear resistance, a photosensitive resin composition for photo-via formation and a photosensitive resin composition for interlayer insulating layers; a photosensitive resin film composed of the photosensitive resin composition and a photosensitive resin film for interlayer insulating layers; a multilayer printed wiring board and a semiconductor package; and a method for manufacturing the multilayer printed wiring board.SOLUTION: A photosensitive resin composition contains (A) a photopolymerizable compound having an ethylenically unsaturated group, (B) an epoxy resin and (C) a photopolymerization initiator. The (A) photopolymerizable compound having an ethylenically unsaturated group includes (A1) a photopolymerizable compound having an acidic substituent and an alicyclic skeleton as well as the ethylenically unsaturated group. The (B) epoxy resin includes (B1) an epoxy resin having a condensed aromatic ring. The number of epoxy functional groups in the (B) component is 1.3-2.3 times the number of acidic substituents in the (A1) component.SELECTED DRAWING: None

Description

Technical Field

[0001] The present disclosure relates to a photosensitive resin composition, a photosensitive resin film, a multilayer printed wiring board and a semiconductor package, and a method for manufacturing a multilayer printed wiring board.

Background Art

[0002] In recent years, miniaturization and high performance of electronic devices have advanced, and in multilayer printed wiring boards, the increase in the number of circuit layers and the densification due to the miniaturization of wiring have been progressing. In particular, in mobile communication devices typified by mobile phones, base station devices thereof, network infrastructure devices such as servers and routers, and large computers, the speed and capacity of signals used have been increasing year by year. Furthermore, with the spread of fifth-generation mobile communication system (5G) antennas using radio waves in frequency bands exceeding 6 GHz and the spread of autonomous driving in automobiles and the like, the demand for low transmission loss has been increasing, and materials having a low dielectric tangent are eagerly desired.

[0003] As a method for manufacturing a printed wiring board, there is a method for manufacturing a multilayer printed wiring board by a build-up method in which an interlayer insulating layer and a conductor circuit layer are sequentially laminated (see, for example, Patent Document 1). In multilayer printed wiring boards, with the miniaturization of circuits, a semi-additive process in which circuits are formed by plating has become the mainstream. In a conventional semi-additive process, for example, (1) a thermosetting resin film is laminated on a conductor circuit, and the thermosetting resin film is cured by heating to form an "interlayer insulating layer". (2) Next, vias for interlayer connection are formed by laser processing, and desmear treatment and roughening treatment are performed by alkali permanganate treatment or the like. (3) Thereafter, electroless copper plating treatment is performed on the substrate, and after pattern formation using a resist, electrolytic copper plating is performed to form a copper circuit layer. (4) Next, the resist is peeled off, and flash etching of the electroless layer is performed to form a copper circuit.

[0004] As described above, laser processing is the mainstream method for forming vias in the interlayer insulating layer formed by curing a thermosetting resin film. However, the reduction in the diameter of vias by laser irradiation using a laser processing machine has reached its limit. Furthermore, in the formation of vias by a laser processing machine, it is necessary to form each via hole one by one. When it is necessary to provide a large number of vias due to high density, it takes a great deal of time to form the vias, and there is a problem that the manufacturing efficiency is poor.

[0005] Under such circumstances, as a method capable of forming a large number of vias at once, a photosensitive resin composition containing (A) an acid-modified vinyl group-containing epoxy resin, (B) a photopolymerizable compound, (C) a photopolymerization initiator, (D) an inorganic filler, and (E) a silane compound, and having a content of the (D) inorganic filler of 10 to 80% by mass is used, and a method of forming a plurality of small-diameter vias at once by a photolithography method has been proposed (see, for example, Patent Document 2). Also, as a method for reducing the dielectric loss tangent of a photosensitive resin composition, a photosensitive resin composition containing (A) an active ester-based curing agent, (B) a carboxyl group-containing radical polymerizable compound, and (D) an epoxy resin has been proposed (see, for example, Patent Document 3).

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0007] In Patent Document 2, as one of the problems, it is an issue to suppress a decrease in the adhesive strength with plated copper due to using a photosensitive resin composition instead of a conventional thermosetting resin composition as the material for the interlayer insulating layer or the surface protective layer. Further, the resolution of vias, and the adhesion to a substrate and chip components made of a silicon material are also issues, and it is stated that these have been solved. Further, in Patent Document 3, it is said that by incorporating an active ester-based curing agent into the photosensitive resin composition used as the material for the interlayer insulating layer, the dielectric loss tangent can be lowered while improving the heat resistance and water resistance. However, in recent years, since the reduction of transmission loss has been progressing in semiconductor peripheral members, the demand for improving the dielectric properties of materials has become even greater. Therefore, there is room for further improvement in the photosensitive resin composition of Patent Document 2 in terms of the dielectric loss tangent. Further, although the photosensitive resin composition of Patent Document 3 essentially requires an active ester-based curing agent, there is also great technical significance in developing a method for reducing the dielectric loss tangent without relying on the active ester-based curing agent.

[0008] Also, before forming the wiring, a desmear treatment (surface roughening treatment) is performed to enhance the adhesion to the copper foil. At this time, if the desmear resistance of the interlayer insulating layer made of the photosensitive resin composition is low, the unevenness becomes large and the outer wall of the via hole is also simultaneously scraped. As a result, connection failures may occur or more metal plating may be required, which becomes a factor in increasing the manufacturing cost. Therefore, the photosensitive layer is required to have not only good via resolution but also excellent desmear resistance, but there is room for improvement in the desmear resistance of the photosensitive layer made of the conventional photosensitive resin composition.

[0009] Therefore, an object of the present invention is to provide a photosensitive resin composition, a photosensitive resin composition for forming a photovia, and a photosensitive resin composition for an interlayer insulating layer that have a low dielectric loss tangent and excellent desmear resistance. Further, to provide a photosensitive resin film and a photosensitive resin film for an interlayer insulating layer made of the photosensitive resin composition, to provide a multilayer printed wiring board and a semiconductor package, and to provide a method for manufacturing the multilayer printed wiring board.

Means for Solving the Problems

[0010] As a result of intensive studies, the present inventors have found that a photosensitive resin composition containing the following components (A) and (B), wherein the component (A) contains a "photopolymerizable compound having an acidic substituent and an alicyclic skeleton together with an ethylenically unsaturated group", and the component (B) contains a "(B1) epoxy resin containing a condensed aromatic ring", and by adjusting the number of epoxy functional groups of the component (B) to a predetermined amount with respect to the number of acidic substituents of the component (A1), the above object can be achieved. That is, the present invention relates to the following [1] to

[17] .

[0011] [1] A photosensitive resin composition containing a (A) photopolymerizable compound having an ethylenically unsaturated group, a (B) epoxy resin, and a (C) photopolymerization initiator, wherein the (A) photopolymerizable compound having an ethylenically unsaturated group contains a (A1) photopolymerizable compound having an acidic substituent and an alicyclic skeleton together with an ethylenically unsaturated group, the (B) epoxy resin contains a (B1) epoxy resin having a condensed aromatic ring, and the number of epoxy functional groups of the (B) component is 1.3 to 2.3 times the number of acidic substituents of the (A1) component. [2] The photosensitive resin composition according to the above [1], wherein the content of the (B1) epoxy resin containing a condensed aromatic ring is 0.5 to 10% by mass based on the total solid content of the photosensitive resin composition. [3] The photosensitive resin composition according to the above [1] or [2], wherein the condensed aromatic ring in the (B1) epoxy resin containing a condensed aromatic ring is at least one selected from the group consisting of a naphthalene ring, an anthracene ring, a phenanthrene ring, a pyrene ring, and a chrysene ring. [4] The photosensitive resin composition according to any one of the above [1] to [3], wherein the (B) component contains a (B2) epoxy resin other than the (B1) component. [5] The photosensitive resin composition according to any one of the above [1] to [4], wherein the (B2) component is at least one selected from the group consisting of a biphenyl type epoxy resin, a biphenyl aralkyl type epoxy resin, a bisphenol type epoxy resin, and an alicyclic skeleton-containing epoxy resin. [6] The photosensitive resin composition according to [4] or [5] above, wherein the content ratio of the (B1) component in the (B) component is 5% by mass or more. [7] The photosensitive resin composition according to any one of [1] to [6] above, further containing (D) an elastomer. [8] The photosensitive resin composition according to any one of [1] to [7] above, further containing (E) an inorganic filler. [9] The photosensitive resin composition according to any one of [1] to [8] above, further containing (F) a curing agent or a curing accelerator.

[10] A photosensitive resin composition for forming a photvia, comprising the photosensitive resin composition according to any one of [1] to [9] above.

[11] A photosensitive resin composition for an interlayer insulating layer, comprising the photosensitive resin composition according to any one of [1] to [9] above.

[12] A photosensitive resin film comprising the photosensitive resin composition according to any one of [1] to [9] above.

[13] A photosensitive resin film for an interlayer insulating layer, comprising the photosensitive resin composition according to any one of [1] to [9] above.

[14] A multilayer printed wiring board comprising an interlayer insulating layer formed using the photosensitive resin composition according to any one of [1] to [9] above.

[15] A multilayer printed wiring board comprising an interlayer insulating layer formed using the photosensitive resin film according to

[12] above.

[16] A semiconductor package obtained by mounting a semiconductor element on the multilayer printed wiring board according to

[14] or

[15] above.

[17] A method for manufacturing a multilayer printed wiring board, comprising the following steps (1) to (4). Step (1): A step of laminating the photosensitive resin film according to

[12] above on one or both sides of a circuit board. Step (2): A step of forming an interlayer insulating layer having vias by exposing and developing the photosensitive resin film laminated in the step (1). Step (3): A step of roughening the vias and the interlayer insulating layer. Step (4): A step of forming a circuit pattern on the interlayer insulating layer. [Effect of the Invention]

[0012] According to the present invention, it is possible to provide a photosensitive resin composition having a low dielectric tangent and excellent desmear resistance, a photosensitive resin composition for forming a photvia, and a photosensitive resin composition for an interlayer insulating layer. Further, it is possible to provide a photosensitive resin film made of the photosensitive resin composition and a photosensitive resin film for an interlayer insulating layer, and a multilayer printed wiring board and a semiconductor package containing an interlayer insulating layer formed using the photosensitive resin composition or the photosensitive resin film. Furthermore, it is possible to provide a method for manufacturing the multilayer printed wiring board. In addition, by using the photosensitive resin composition of the present invention, the resolution of vias also becomes good.

Brief Description of the Drawings

[0013]

Figure 1

Embodiments for Carrying Out the Invention

[0014] In the numerical ranges described in this specification, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples. Further, the lower limit value and the upper limit value of the numerical range can be arbitrarily combined with the lower limit value or the upper limit value of other numerical ranges, respectively. Furthermore, in this specification, the content of each component in the photosensitive resin composition means the total content of the plurality of substances present in the photosensitive resin composition when there are a plurality of substances corresponding to each component, unless otherwise specified. In this specification, the "number of ring-forming carbon atoms" is the number of carbon atoms necessary to form a ring, and does not include the number of carbon atoms of substituents that the ring has. For example, both the cyclohexane skeleton and the methylcyclohexane skeleton have 6 ring-forming carbon atoms. Also, aspects in which the matters described in this specification are arbitrarily combined are also included in the present invention.

[0015] [Photosensitive Resin Composition, Photosensitive Resin Composition for Photo Via Formation, and Photosensitive Resin Composition for Interlayer Insulation Layer] The photosensitive resin composition according to one embodiment of the present invention (hereinafter sometimes simply referred to as this embodiment) is a photosensitive resin composition containing (A) a photopolymerizable compound having an ethylenically unsaturated group, (B) an epoxy resin, and (C) a photopolymerization initiator, wherein the (A) photopolymerizable compound having an ethylenically unsaturated group includes (A1) a photopolymerizable compound having an acidic substituent and an alicyclic skeleton together with the ethylenically unsaturated group, the (B) epoxy resin includes (B1) an epoxy resin having a condensed aromatic ring, and the number of epoxy functional groups of the (B) component is 1.3 to 2.3 times the number of acidic substituents of the (A1) component. In the present specification, the above components may be referred to as the (A) component, the (B) component, the (C) component, the (A1) component, the (B1) component, etc., respectively, and other components may also be abbreviated in the same way. Further, in the present specification, the "resin component" refers to the (A) component, the (B) component, etc., and also includes other components that may be contained as necessary (for example, the (C) component, the (D) component, the (F) component, the (H) component, etc.), but does not include the (E) inorganic filler and inorganic compounds such as (G) pigments that may be contained as necessary and will be described later. Also, the "solid content" refers to the non-volatile content excluding volatile substances such as water and solvents contained in the photosensitive resin composition, and indicates the components that remain without volatilization when the resin composition is dried, and also includes those in a liquid state, a treacle state, and a wax state at room temperature near 25°C.

[0016] Since the photosensitive resin composition of this embodiment is suitable for via formation by photolithography (also referred to as photo via formation), the present invention also provides a photosensitive resin composition for photo via formation. Further, since the photosensitive resin composition of this embodiment has a low dielectric tangent, excellent desmear resistance, and good via resolution, it is useful as an interlayer insulation layer of a multilayer printed wiring board. Therefore, the present invention also provides a photosensitive resin composition for an interlayer insulation layer. In the present specification, when referring to a photosensitive resin composition, it also includes a photosensitive resin composition for photo via formation and a photosensitive resin composition for an interlayer insulation layer. Incidentally, the photosensitive resin composition of the present embodiment is useful as a negative photosensitive resin composition. Hereinafter, each component that the photosensitive resin composition may contain will be described in detail.

[0017] <(Photopolymerizable compound having an ethylenically unsaturated group)> The photosensitive resin composition of the present embodiment contains, as component (A), a photopolymerizable compound having an ethylenically unsaturated group. Examples of the ethylenically unsaturated group that component (A) has include a vinyl group, an allyl group, a propargyl group, a butenyl group, an ethynyl group, a phenylethynyl group, a maleimide group, a nadimide group, a (meth)acryloyl group, and the like. As the ethylenically unsaturated group, a (meth)acryloyl group is preferable. In the present embodiment, component (A) includes “(A1) Photopolymerizable compound having an acidic substituent and an alicyclic skeleton together with an ethylenically unsaturated group” described later. By component (A) including component (A1), the resolution of vias is good, and also, for example, a sufficiently low dielectric tangent is obtained even in a high frequency band of 10 GHz or higher. Hereinafter, component (A1) will be described in detail.

[0018] ((A1) Photopolymerizable compound having an acidic substituent and an alicyclic skeleton together with an ethylenically unsaturated group) Examples of the ethylenically unsaturated group that component (A1) has include the same ones as the ethylenically unsaturated groups described above, and at least one selected from the group consisting of a vinyl group, an allyl group, a propargyl group, a butenyl group, an ethynyl group, a phenylethynyl group, a maleimide group, a nadimide group, and a (meth)acryloyl group is preferable, a vinyl group, an allyl group, a (meth)acryloyl group are more preferable, and a (meth)acryloyl group is even more preferable. Examples of the acidic substituent that component (A1) has include at least one selected from the group consisting of a carboxyl group, a sulfonic acid group, a phenolic hydroxyl group, and the like, and a carboxyl group is more preferable.

[0019] As the alicyclic skeleton of the (A1) component, from the viewpoints of via resolution and low dielectric constant, an alicyclic skeleton having 5 to 20 carbon atoms forming the ring is preferable, an alicyclic skeleton having 5 to 18 carbon atoms forming the ring is more preferable, an alicyclic skeleton having 6 to 18 carbon atoms forming the ring is further preferable, an alicyclic skeleton having 8 to 14 carbon atoms forming the ring is particularly preferable, and an alicyclic skeleton having 8 to 12 carbon atoms forming the ring is most preferable. Further, from the viewpoints of via resolution and low dielectric constant, the alicyclic skeleton preferably consists of two or more rings, more preferably consists of 2 to 4 rings, and further preferably consists of 3 rings. Examples of the alicyclic skeleton having two or more rings include a norbornane skeleton, a decalin skeleton, a bicycloundecane skeleton, a saturated dicyclopentadiene skeleton, and the like. As the alicyclic skeleton, from the viewpoints of via resolution and low dielectric constant, a saturated dicyclopentadiene skeleton is preferable, and an alicyclic skeleton (saturated dicyclopentadiene skeleton) represented by the following general formula (a) is more preferable. [Chemical formula] (In general formula (a), R A1 represents an alkyl group having 1 to 12 carbon atoms and may be substituted at any position in the above alicyclic skeleton. m 1 is an integer of 0 to 6. * is a bonding site to another structure.)

[0020] In general formula (a), examples of the alkyl group having 1 to 12 carbon atoms represented by R A1 include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group, an n-pentyl group, and the like. As the alkyl group, an alkyl group having 1 to 6 carbon atoms is preferable, an alkyl group having 1 to 3 carbon atoms is more preferable, and a methyl group is further preferable. m 1 is an integer of 0 to 6, preferably an integer of 0 to 2, and more preferably 0. m 1 When it is an integer of 2 to 6, the plurality of R A1 may be the same or different from each other. Further, the plurality of R A1It may be substituted on the same carbon atom or different carbon atoms as long as possible. * is a bonding site to another structure and may be bonded to any carbon atom on the alicyclic skeleton, but is preferably bonded to the carbon atom represented by 1 or 2 in the following general formula (a') and the carbon atom represented by any one of 3 to 4.

[0021]

Chemical formula

[0022] As the component (A1), from the viewpoints of being alkali-developable and having excellent via resolution, adhesion strength to plated copper, crack resistance, and electrical insulation reliability, a compound obtained by modifying (a1) an alicyclic skeleton-containing epoxy resin with (a2) an ethylenically unsaturated group-containing organic acid [hereinafter sometimes referred to as the component (A')] is reacted with (a3) a saturated group- or unsaturated group-containing polybasic acid anhydride, and the "epoxy derivative containing an acid-modified ethylenically unsaturated group and an alicyclic skeleton" (A1-1) is preferred.

[0023] -(a1) Alicyclic skeleton-containing epoxy resin- The above-mentioned (a1) alicyclic skeleton-containing epoxy resin is preferably an epoxy resin having two or more epoxy groups. Epoxy resins are classified into glycidyl ether type epoxy resins, glycidyl amine type epoxy resins, glycidyl ester type epoxy resins, etc. Among these, glycidyl ether type epoxy resins are preferred.

[0024] In the present invention, as the epoxy resin, at least an epoxy resin having an alicyclic skeleton is used. The alicyclic skeleton is described in the same manner as the alicyclic skeleton of the component (A1) described above, and the preferred embodiments are also the same. (a1) As the alicyclic skeleton-containing epoxy resin, an epoxy resin represented by the following general formula (a1-1) is preferable. Also, an epoxy resin having a structural unit represented by the following general formula (a1-2) is also preferable. [Chemical formula] (In the general formula (a1-1), R A1 represents an alkyl group having 1 to 12 carbon atoms and may be substituted anywhere in the above alicyclic skeleton. R A2 represents an alkyl group having 1 to 12 carbon atoms. m 1 is an integer from 0 to 6, m 2 is an integer from 0 to 3. n is from 0 to 10.) [Chemical formula] (In the general formula (a1-2), R A1 represents an alkyl group having 1 to 12 carbon atoms and may be substituted anywhere in the above alicyclic skeleton. m 1 is an integer from 0 to 6.)

[0025] In the general formulas (a1-1) and (a1-2), R A1 is the same as R A1 in the general formula (a), and the preferred embodiments are also the same. As the alkyl group having 1 to 12 carbon atoms represented by R A2 in the general formula (a1-1), for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group, an n-pentyl group, etc. can be mentioned. As the alkyl group, an alkyl group having 1 to 6 carbon atoms is preferable, an alkyl group having 1 to 3 carbon atoms is more preferable, and a methyl group is even more preferable. m 1 in the general formulas (a1-1) and (a1-2) is the same as m 1 in the general formula (a), and the preferred embodiments are also the same. m 2 in the general formula (a1-1) is an integer from 0 to 3, 0 or 1 is preferable, and 0 is more preferable. In the general formula (a1-1), n represents the number of repetitions of the structural unit within the parentheses and is from 0 to 10. Usually, since the epoxy resin is a mixture of those with different numbers of repetitions of the structural unit within the parentheses, in that case, n is represented by the average value of the mixture. Preferably, n is from 2 to 10.

[0026] (a1) As the alicyclic skeleton-containing epoxy resin, commercially available products may be used. Examples of commercially available products include XD-1000 (manufactured by Nippon Kayaku Co., Ltd., trade name), EPICLON HP-7200L, EPICLON HP-7200, EPICLON HP-7200HH, EPICLON HP-7200HHH (manufactured by DIC Corporation, trade name, "EPICLON" is a registered trademark), etc.

[0027] (a1) As the epoxy resin, an epoxy resin other than the epoxy resin having the alicyclic skeleton (hereinafter sometimes referred to as other epoxy resins) may be used in combination. Examples of other epoxy resins include bisphenol-based epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin; bisphenol-based novolak type epoxy resins such as bisphenol A novolak type epoxy resin, bisphenol F novolak type epoxy resin; novolak type epoxy resins other than the above bisphenol-based novolak type epoxy resins such as phenol novolak type epoxy resin, cresol novolak type epoxy resin, biphenyl novolak type epoxy resin; phenol aralkyl type epoxy resin; biphenyl aralkyl type epoxy resin; stilbene type epoxy resin; naphthalene type epoxy resin, naphthol novolak type epoxy resin, naphthol type epoxy resin, naphthol aralkyl type epoxy resin, naphthylene ether type epoxy resin, etc., which are naphthalene skeleton-containing type epoxy resins; biphenyl type epoxy resin; xylylene type epoxy resin; dihydroanthracene type epoxy resin; aliphatic chain type epoxy resin; rubber-modified epoxy resin, etc.

[0028] -(a2) Ethylenically unsaturated group-containing organic acid - The (a2) ethylenically unsaturated group-containing organic acid is not particularly limited, but an ethylenically unsaturated group-containing monocarboxylic acid is preferred. The ethylenically unsaturated group is as described for the ethylenically unsaturated group in the (A1) component. Examples of the ethylenically unsaturated group-containing monocarboxylic acid include acrylic acid; acrylic acid derivatives such as dimers of acrylic acid, methacrylic acid, β-furfurylacrylic acid, β-styrylacrylic acid, cinnamic acid, crotonic acid, and α-cyanocinnamic acid; half-ester compounds that are reaction products of hydroxyl group-containing acrylates and dibasic acid anhydrides; half-ester compounds that are reaction products of ethylenically unsaturated group-containing monoglycidyl ethers or ethylenically unsaturated group-containing monoglycidyl esters and dibasic acid anhydrides; and the like. Among these, acrylic acid is preferred. (The (a2) component may be used alone or in combination of two or more.

[0029] The half-ester compound can be obtained, for example, by reacting a hydroxyl group-containing acrylate, an ethylenically unsaturated group-containing monoglycidyl ether, or an ethylenically unsaturated group-containing monoglycidyl ester with a dibasic acid anhydride in an equimolar ratio.

[0030] Examples of the hydroxyl group-containing acrylate, ethylenically unsaturated group-containing monoglycidyl ether, and ethylenically unsaturated group-containing monoglycidyl ester used in the synthesis of the half-ester compound, which is an example of the (a2) component, 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, glycidyl methacrylate, and the like.

[0031] As the dibasic acid anhydride used for synthesizing the semi-ester compound, those containing a saturated group or those containing an unsaturated group may be used. 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, itaconic anhydride, and the like.

[0032] Although not particularly limited, in the reaction between the component (a1) and the component (a2), it is preferable to react the component (a2) at a ratio of 0.6 to 1.05 equivalents with respect to 1 equivalent of the epoxy group of the component (a1), and it may also be reacted at a ratio of 0.8 to 1.0 equivalents. By reacting at such a ratio, the photopolymerizability is improved, that is, the photosensitivity is increased, and the resolution of the via tends to be improved.

[0033] The component (a1) and the component (a2) 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; and petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha.

[0034] Furthermore, it is preferable to use a catalyst to promote the reaction between the component (a1) and the component (a2). Examples of the catalyst include amine catalysts such as triethylamine and benzylmethylamine; quaternary ammonium salt catalysts such as methyltriethylammonium chloride, benzyltrimethylammonium chloride, benzyltrimethylammonium bromide, and benzyltrimethylammonium iodide; phosphine catalysts such as triphenylphosphine, etc. Among these, phosphine catalysts are preferred, and triphenylphosphine is more preferred. The amount of the catalyst used is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, and still more preferably 0.1 to 2 parts by mass with respect to a total of 100 parts by mass of the component (a1) and the component (a2). With the above-mentioned amount used, the reaction between the component (a1) and the component (a2) tends to be promoted.

[0035] Also, for the purpose of preventing polymerization during the reaction, it is preferable to use a polymerization inhibitor. Examples of the polymerization inhibitor include hydroquinone, methylhydroquinone, hydroquinone monomethyl ether, catechol, pyrogallol, etc. When using a polymerization inhibitor, the amount used is preferably 0.01 to 1 part by mass, more preferably 0.02 to 0.8 part by mass, and still more preferably 0.05 to 0.5 part by mass with respect to a total of 100 parts by mass of the component (a1) and the component (a2) from the viewpoint of improving the storage stability of the composition.

[0036] The reaction temperature between the component (a1) and the component (a2) is preferably 60 to 150 °C, more preferably 70 to 120 °C, and still more preferably 80 to 110 °C from the viewpoint of productivity.

[0037] Thus, it is presumed that the component (A') formed by reacting the component (a1) and the component (a2) has a hydroxyl group formed by a ring-opening addition reaction between the epoxy group of the component (a1) and the carboxyl group of the component (a2).

[0038] -(a3) Polybasic acid anhydride- As the component (a3), it may contain a saturated group or an unsaturated group. Examples of the component (a3) include succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride, itaconic anhydride, etc. Among these, from the viewpoint of the resolution of the film, tetrahydrophthalic anhydride is preferably used.

[0039] By further reacting the obtained component (A’) with a component (a3) containing a saturated or unsaturated group, it is presumed that the hydroxyl group of the component (A’) (including the hydroxyl group originally present in the component (a1)) and the acid anhydride group of the component (a3) are semi-esterified to form an (A1-1) acid-modified ethylenically unsaturated group and alicyclic skeleton-containing epoxy derivative.

[0040] In the reaction between the component (A’) and the component (a3), for example, by reacting 0.1 to 1.0 equivalent of the component (a3) with respect to 1 equivalent of the hydroxyl group in the component (A’), the acid value of the (A1-1) acid-modified ethylenically unsaturated group and alicyclic skeleton-containing epoxy derivative can be adjusted. The acid value of the (A1-1) acid-modified ethylenically unsaturated group and alicyclic skeleton-containing epoxy derivative is preferably 20 to 150 mgKOH / g, more preferably 30 to 120 mgKOH / g, and even more preferably 40 to 100 mgKOH / g. If the acid value is 20 mgKOH / g or more, the solubility of the photosensitive resin composition in a dilute alkaline solution tends to be excellent, and if it is 150 mgKOH / g or less, the electrical properties of the cured film tend to be improved.

[0041] From the viewpoint of productivity, the reaction temperature between the component (A’) and the component (a3) is preferably 50 to 150 °C, more preferably 60 to 120 °C, and even more preferably 70 to 100 °C.

[0042] As described above, the photopolymerizable compound having an acidic substituent and an alicyclic skeleton together with the (A1) ethylenically unsaturated group is not particularly limited, but is preferably represented by the following general formula (A-1). [Chemical formula] (In the general formula (A-1), R A1 represents an alkyl group having 1 to 12 carbon atoms and may be substituted anywhere in the above alicyclic skeleton. R A2 represents an alkyl group having 1 to 12 carbon atoms. R A3 is an organic group having an ethylenically unsaturated group, an organic group having an ethylenically unsaturated group and an acidic substituent, or a glycidyl group, and at least one R A3 is an organic group having an ethylenically unsaturated group and an acidic substituent. m 1 is an integer of 0 to 6, m 2 is an integer of 0 to 3. n is 0 to 10.)

[0043] R A1 , R A2 , m 1 , m 2 and n in the general formula (a1-1) are the same as those in the general formula (a1-1), and the preferred ones are also the same. R A3 is as defined above, but the glycidyl group in the general formula (a1-1) corresponds to the site formed by reacting with the (a2) component and the (a3) component, and is defined in consideration of the fact that some of the glycidyl groups remain unreacted. That is, the "organic group having an ethylenically unsaturated group" which is an option of R A3 is a group derived from the (a2), and the "organic group having an ethylenically unsaturated group and an acidic substituent" is a group derived from the (a2) and (a3) components. If the (a2) and (a3) components react with all the glycidyl groups in the general formula (a1-1), then R A3becomes an "organic group having an ethylenically unsaturated group and an acidic substituent", but the site that reacts only with the component (a2) becomes an "organic group having an ethylenically unsaturated group", and the site that does not react with either of the components (a2) and (a3) becomes a "glycidyl group".

[0044] ((A1) Molecular weight of the photopolymerizable compound having an acidic substituent and an alicyclic skeleton together with an ethylenically unsaturated group) The weight average molecular weight (Mw) of the component (A1) is preferably 1,000 to 30,000, more preferably 2,000 to 25,000, and still more preferably 3,000 to 18,000. If it is within this range, the adhesive strength, heat resistance, and electrical insulation reliability with plated copper are improved. In particular, it is preferable that the weight average molecular weight (Mw) of the acid-modified ethylenically unsaturated group and alicyclic skeleton-containing epoxy derivative (A1-1) is within the above range. Here, in this specification, the weight average molecular weight is a value measured by gel permeation chromatography (GPC) (manufactured by Tosoh Corporation) using a calibration curve of standard polystyrene, and more specifically, it is a value measured according to the method described below. <Method for measuring weight average molecular weight> The weight average molecular weight was measured with the following GPC measuring device and measuring conditions, and the value converted using the calibration curve of standard polystyrene was taken as the weight average molecular weight. Also, for the preparation of the calibration curve, 5 sample sets ("PStQuick MP-H" and "PStQuick B", manufactured by Tosoh Corporation) were used as standard polystyrenes. (GPC measuring device) GPC device: High-speed GPC device "HCL-8320GPC", detector is a differential refractometer or UV, manufactured by Tosoh Corporation Column: Column TSKgel SuperMultipore HZ-H (column length: 15 cm, column inner diameter: 4.6 mm), manufactured by Tosoh Corporation (Measuring conditions) Solvent: Tetrahydrofuran (THF) Measuring temperature: 40 °C Flow rate: 0.35 mL / min Sample concentration: 10 mg / THF 5 mL Injection volume: 20 μL

[0045] ((A2-1) Acid-modified ethylene unsaturated group-containing epoxy derivative without an alicyclic skeleton) (A) As the photopolymerizable compound having an ethylenically unsaturated group, further, a compound obtained by reacting (a21) an epoxy resin (however, not containing an alicyclic skeleton) with (a22) an ethylenically unsaturated group-containing organic acid and then reacting with (a23) a saturated group or unsaturated group-containing polybasic acid anhydride, an embodiment including the “(A2-1) acid-modified ethylene unsaturated group-containing epoxy derivative without an alicyclic skeleton” may also be used.

[0046] The (a21) epoxy resin is not particularly limited as long as it is an epoxy resin without an alicyclic skeleton, and examples include glycidyl ether type epoxy resins, glycidyl amine type epoxy resins, glycidyl ester type epoxy resins, and the like. Among these, glycidyl ether type epoxy resins are preferred. In addition, the (a21) epoxy resin is classified into various epoxy resins according to the difference in the main skeleton, and in each of the above types of epoxy resins, it is further classified as follows. Specifically, bisphenol-based epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, and bisphenol S type epoxy resin; bisphenol-based novolac type epoxy resins such as bisphenol A novolac type epoxy resin and bisphenol F novolac type epoxy resin; novolac type epoxy resins other than the above bisphenol-based novolac type epoxy resins, such as phenol novolac type epoxy resin, cresol novolac type epoxy resin, and biphenyl novolac type epoxy resin; phenol aralkyl type epoxy resin; stilbene type epoxy resin; naphthalene skeleton-containing epoxy resins such as naphthalene type epoxy resin, naphthol novolac type epoxy resin, naphthol type epoxy resin, naphthol aralkyl type epoxy resin, and naphthylene ether type epoxy resin; biphenyl type epoxy resin; biphenyl aralkyl type epoxy resin; xylylene type epoxy resin; dihydroanthracene type epoxy resin; aliphatic chain epoxy resin; rubber-modified epoxy resin, etc. Among these, bisphenol-based novolac type epoxy resins are preferred, and bisphenol F novolac type epoxy resin is more preferred.

[0047] The (a22) ethylenically unsaturated group-containing organic acid and the (a23) saturated group or unsaturated group-containing polybasic acid anhydride are described in the same manner as the description of the (a2) ethylenically unsaturated group-containing organic acid and the (a3) saturated group or unsaturated group-containing polybasic acid anhydride, and the preferred embodiments are also the same. In addition, as a method of reacting the (a23) component with the compound obtained by modifying the (a21) component with the (a22) component, reference can be made to the method of reacting the (a3) component with the compound obtained by modifying the (a1) component with the (a2) component.

[0048] (A2-1) As the acid-modified ethylenically unsaturated group-containing epoxy derivative that does not contain an alicyclic skeleton, commercially available products may be used. Examples of commercially available products include CCR-1218H, CCR-1159H, CCR-1222H, PCR-1050, TCR-1335H, ZAR-1035, ZAR-2001H, UXE-3024, ZFR-1185, ZCR-1569H, ZXR-1807, ZCR-6000, ZCR-8000 (above, manufactured by Nippon Kayaku Co., Ltd., trade name), UE-9000, UE-EXP-2810PM, UE-EXP-3045 (above, manufactured by DIC Corporation, trade name), etc.

[0049] When the component (A) contains both the component (A1) (or component (A1-1)) and the component (A2-1), from the perspective of the balance of properties such as via resolution, adhesion strength to plated copper, crack resistance, and electrical insulation reliability, the content ratio of the component (A1) (or component (A1-1)) to the component (A2-1) [(A1) or (A1-1) / (A2-1)] is preferably 20 / 80 to 99 / 1, more preferably 50 / 50 to 99 / 1, still more preferably 60 / 40 to 99 / 1, particularly preferably 60 / 40 to 85 / 15, and most preferably 65 / 35 to 80 / 20 in terms of mass ratio.

[0050] ((A2-2) Styrene-maleic acid resin) As the photopolymerizable compound having an ethylenically unsaturated group (A), “(A2-2) Styrene-maleic acid resin” such as a hydroxyethyl (meth) acrylate-modified product of a styrene-maleic anhydride copolymer can also be used in combination. The component (A2-2) does not contain an alicyclic skeleton. The component (A2-2) may be used alone or in combination of two or more.

[0051] ((A2-3) Epoxy-based polyurethane resin) In addition, as the photopolymerizable compound having an ethylenically unsaturated group, a " (A2-3) epoxy-based polyurethane resin " obtained by reacting a compound obtained by modifying the (a21) epoxy resin with the (a22) ethylenically unsaturated group-containing organic acid, that is, the (A') component, and an isocyanate compound can also be used in combination. The (A2-3) component does not contain an alicyclic skeleton. The (A2-3) component may be used alone or in combination of two or more.

[0052] ((A) component other than the above) As the photopolymerizable compound having an ethylenically unsaturated group (A), from the viewpoint of enhancing the chemical resistance after curing (exposure) and increasing the difference in the developability resistance between the exposed portion and the unexposed portion, as the photopolymerizable compound having an ethylenically unsaturated group (A), furthermore, (Ai) a monofunctional vinyl monomer having one polymerizable ethylenically unsaturated group, (Aii) a bifunctional vinyl monomer having two polymerizable ethylenically unsaturated groups, and (Aiii) at least one selected from the group consisting of polyfunctional vinyl monomers having at least three polymerizable ethylenically unsaturated groups. An embodiment containing at least one is preferable, and an embodiment containing the (Aiii) component is more preferable. As the (Ai) to (Aiii) components, those having a molecular weight of 1,000 or less are preferable. However, in the present invention, the (Ai) to (Aiii) components do not include the (A1) component.

[0053] ((Ai) Monofunctional vinyl monomer) Examples of the monofunctional vinyl monomer having one polymerizable ethylenically unsaturated group include (meth) acrylic acid, (meth) acrylic acid alkyl esters, and the like. Examples of the (meth) acrylic acid alkyl ester include (meth) acrylic acid methyl ester, (meth) acrylic acid ethyl ester, (meth) acrylic acid butyl ester, (meth) acrylic acid 2-ethylhexyl ester, (meth) acrylic acid hydroxyethyl ester, and the like. The (Ai) component may be used alone or in combination of two or more.

[0054] ((Aii) Bifunctional vinyl monomer) Examples of the bifunctional vinyl monomer having two polymerizable ethylenically unsaturated groups include polyethylene glycol di(meth)acrylate, trimethylolpropane di(meth)acrylate, polypropylene glycol di(meth)acrylate, 2,2-bis(4-(meth)acryloxypolyethoxypolypropoxyphenyl)propane, bisphenol A diglycidyl ether di(meth)acrylate, and the like. Component (Aii) may be used alone or in combination of two or more.

[0055] ((Aiii) Polyfunctional vinyl monomer) Examples of the polyfunctional vinyl monomer having at least three polymerizable ethylenically unsaturated groups include (meth)acrylate compounds having a skeleton derived from trimethylolpropane such as trimethylolpropane tri(meth)acrylate; (meth)acrylate compounds having a skeleton derived from tetramethylolmethane such as tetramethylolmethane tri(meth)acrylate and tetramethylolmethane tetra(meth)acrylate; (meth)acrylate compounds having a skeleton derived from pentaerythritol such as pentaerythritol tri(meth)acrylate and pentaerythritol tetra(meth)acrylate; (meth)acrylate compounds having a skeleton derived from dipentaerythritol such as dipentaerythritol penta(meth)acrylate and dipentaerythritol hexa(meth)acrylate; (meth)acrylate compounds having a skeleton derived from ditrimethylolpropane such as ditrimethylolpropane tetra(meth)acrylate; (meth)acrylate compounds having a skeleton derived from diglycerin, and the like. Among these, from the viewpoint of enhancing the chemical resistance after curing (exposure) and increasing the difference in the developer resistance between the exposed part and the unexposed part, (meth)acrylate compounds having a skeleton derived from dipentaerythritol are preferable, and dipentaerythritol penta(meth)acrylate is more preferable. Component (Aiii) may be used alone or in combination of two or more. Here, the “(meth)acrylate compound having a skeleton derived from XXX” (where XXX is a compound name) means an esterified product of XXX and (meth)acrylic acid, and the esterified product includes compounds modified with an alkyleneoxy group.

[0056] (Content of component (A)) The content of component (A) is not particularly limited, but from the viewpoints of heat resistance, electrical properties, and chemical resistance, it is preferably 5 to 60% by mass, more preferably 5 to 50% by mass, still more preferably 10 to 40% by mass, particularly preferably 10 to 30% by mass, and most preferably 15 to 25% by mass based on the total solid content of the photosensitive resin composition.

[0057] Component (A) is not particularly limited, but from the viewpoint of photosensitive characteristics, it is preferable to use the component (A1) and the component (Aiii) in combination. In this case, the content ratio [(A1) / (Aiii)] (mass ratio) of the component (A1) and the component (Aiii) is preferably 1.5 to 20, more preferably 2 to 10, still more preferably 2.5 to 7, and particularly preferably 2.5 to 5. Also, the content ratio of the component (A1) to the total amount of the component (A) is preferably 20 to 95% by mass, more preferably 40 to 90% by mass, still more preferably 55 to 90% by mass, and particularly preferably 65 to 85% by mass from the viewpoint of via resolution. <(B) Epoxy resin>

[0058] The epoxy resin is preferably an epoxy resin having two or more epoxy groups. Epoxy resins are classified into glycidyl ether type epoxy resins, glycidyl amine type epoxy resins, glycidyl ester type epoxy resins, etc. Among these, glycidyl ether type epoxy resins are preferred.

[0059] In addition, epoxy resins are classified into various types according to the difference in the main skeleton, and in each of the above types of epoxy resins, they are further classified as follows. Specifically, bisphenol-based epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, and bisphenol S type epoxy resin; bisphenol-based novolac type epoxy resins such as bisphenol A novolac type epoxy resin and bisphenol F novolac type epoxy resin; novolac type epoxy resins other than the above bisphenol-based novolac type epoxy resins, such as phenol novolac type epoxy resin, cresol novolac type epoxy resin, and biphenyl novolac type epoxy resin; phenol aralkyl type epoxy resin; stilbene type epoxy resin; naphthalene skeleton-containing epoxy resins such as naphthalene type epoxy resin, naphthol novolac type epoxy resin, naphthol type epoxy resin, naphthol aralkyl type epoxy resin, and naphthylene ether type epoxy resin; biphenyl type epoxy resin; biphenyl aralkyl type epoxy resin; xylylene type epoxy resin; dihydroanthracene type epoxy resin; alicyclic skeleton-containing epoxy resins such as dicyclopentadiene type epoxy resin; heterocyclic epoxy resin; spiro ring-containing epoxy resin; cyclohexanedimethanol type epoxy resin; trimethylol type epoxy resin; aliphatic chain-like epoxy resins such as branched alkyl chain-like epoxy resin; rubber-modified epoxy resin; and so on. Component (B) may be used alone or in combination of two or more.

[0060] In this embodiment, in particular, as the component (B), it contains (B1) an epoxy resin having a condensed aromatic ring. The exact reason for achieving a low dielectric tangent by including the component (B1) is unknown, but it is presumed that due to the influence of the rigidity of the condensed aromatic ring, etc., when an external electric field is applied, the epoxy resin becomes less responsive to the change in the electric field and the molecular vibration is reduced, resulting in a decrease in the calorific value and a reduction in the transmission loss, and thus the dielectric tangent becomes low. In the epoxy resin containing the condensed aromatic ring (B1), the number of condensed rings of the condensed aromatic ring is preferably 2 to 6 rings, more preferably 2 to 3 rings, and still more preferably 2 rings. As the condensed aromatic ring, for example, it is preferably at least one selected from the group consisting of a naphthalene ring, an anthracene ring, a phenanthrene ring, a pyrene ring, and a chrysene ring. From the viewpoints of easy availability and low dielectric tangent, a naphthalene ring is more preferable. Epoxy resins containing a naphthalene ring are usually referred to as naphthol-type epoxy resins, naphthalene-type epoxy resins, naphthalene skeleton-containing epoxy resins, etc. Commercially available products can also be used as the epoxy resin containing a naphthalene ring. Examples of commercially available products include naphthol-type epoxy resins ("Epoto (registered trademark) ESN-475V" manufactured by Nippon Steel Chemical & Material Co., Ltd.), naphthalene-type epoxy resins ("HP4032D", "HP4710" manufactured by DIC Corporation), naphthalene skeleton-containing polyfunctional epoxy resins ("NC-7000" manufactured by Nippon Kayaku Co., Ltd.), etc.

[0061] As the epoxy resin containing the naphthalene ring, for example, epoxy resins represented by any of the following general formulas (I) to (VIII) are preferably mentioned.

[0062] [Chemical formula] (In general formula (I), R 1 represents a hydrogen atom or a halogen-free organic group, and n 1 represents an integer from 1 to 10.)

[0063] [Chemical formula] (In general formula (II), n 2 represents an integer from 1 to 10.)

[0064] [Chemical formula] (In general formula (III), n 3 represents an integer from 1 to 10.)

[0065]

Chemical formula

[0066]

Chemical formula

[0067]

Chemical formula

[0068]

Chemical formula

[0069] R in the general formula (I) 1 and R in the general formula (VII) 2 Examples of the halogen-free organic group represented include alkyl groups having 1 to 10 carbon atoms (preferably 1 to 6, more preferably 1 to 3) such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group; aryl groups having 6 to 18 ring-forming carbon atoms (preferably 6 to 12) such as phenyl group, naphthyl group; aralkyl groups having a total of 7 to 18 carbon atoms (preferably 7 to 13) such as benzyl group; heteroaromatic groups having 5 to 18 ring-forming atoms (preferably 5 to 12) such as pyridyl group, etc. Also, Z in the general formula (VI) 1 and Z in the general formula (VII)2 Examples of the halogen-free organic group represented by include an alkylene group having 1 to 10 carbon atoms (preferably 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms) such as a methylene group, a dimethylene group, a trimethylene group, a tetramethylene group, and a pentamethylene group; an arylene group having 6 to 18 ring-forming carbon atoms (preferably 6 to 12 carbon atoms) such as a phenylene group, a naphthylene group, and an anthrylene group; and a heteroaromatic group having 5 to 18 ring-forming atoms (preferably 5 to 12 ring-forming atoms) such as a pyridylene group.

[0070] Among the epoxy resins containing the above naphthalene ring, from the viewpoint of low dielectric properties, the epoxy resin represented by the general formula (I) is preferable. Further, in the epoxy resin represented by the general formula (I), R 1 An epoxy resin in which is a methyl group is more preferable.

[0071] In the present embodiment, as the component (B), it may contain (B2) an epoxy resin other than the component (B1). From the viewpoint of suppressing undercut of vias by enhancing ultraviolet absorption, etc., it is preferable to contain a component (B2) that is difficult to absorb ultraviolet rays. Examples of the epoxy resin other than the component (B1) include the same ones as those exemplified for the epoxy resin (however, excluding the epoxy resin having a condensed aromatic ring). The component (B2) that is difficult to absorb ultraviolet rays is not particularly limited, but preferably includes, for example, a biphenyl type epoxy resin, a biphenyl aralkyl type epoxy resin, a bisphenol type epoxy resin, and an aliphatic chain type epoxy resin. From the viewpoints of difficulty in absorbing ultraviolet rays and low dielectric tangent, an aliphatic chain type epoxy resin is more preferable. When the component (B) contains the component (B2) together with the component (B1), as the component (B2), at least one selected from the group consisting of a biphenyl type epoxy resin, a biphenyl aralkyl type epoxy resin, a bisphenol type epoxy resin, and an aliphatic chain type epoxy resin is preferable, and a biphenyl type epoxy resin is more preferable. The bisphenol type epoxy resin may be, for example, a bisphenol F type epoxy resin. When the (B) component contains the (B2) component together with the (B1) component, the content ratio of the (B1) component in the (B) component is preferably 5% by mass or more from the viewpoint of low dielectric loss tangent. Considering the resolution of vias, the adhesive strength with plated copper, crack resistance, electrical insulation reliability, etc., it is more preferably 5 to 95% by mass, still more preferably 25 to 90% by mass, particularly preferably 50 to 85% by mass, and most preferably 60 to 85% by mass.

[0072] Commercially available products can also be used as the (B2) component. For example, bisphenol A type epoxy resins ("jER828EL", "YL980" manufactured by Mitsubishi Chemical Corporation), bisphenol F type epoxy resins ("jER806H", "YL983U" manufactured by Mitsubishi Chemical Corporation, "YSLV-80XY" manufactured by Nippon Steel Chemical & Material Co., Ltd.), epoxy resins having a biphenyl structure ("NC-3000-H", "NC-3000-L", "NC-3500" manufactured by Nippon Kayaku Co., Ltd.), manufactured by Mitsubishi Chemical Corporation ("YX4000HK", "YL6121"), anthracene type epoxy resins ("YX8800" manufactured by Mitsubishi Chemical Corporation), glycerol type epoxy resins ("ZX1542" manufactured by Nippon Steel Chemical & Material Co., Ltd.), naphthylene ether type epoxy resins ("EXA7311-G4" manufactured by DIC Corporation), cresol novolak type epoxy resins ("EPICLON N-680" manufactured by DIC Corporation), branched alkyl chain epoxy resins ("FOLDI-E201" manufactured by Nissan Chemical Industries, Ltd.), and in addition, "YL9057" (a polyfunctional novolak type epoxy resin), "YL9058", etc. manufactured by Mitsubishi Chemical Corporation.

[0073] (Content of the (B1) component) (B1) The content of the epoxy resin containing a condensed aromatic ring is preferably 0.5 to 40% by mass, more preferably 1 to 30% by mass, still more preferably 2 to 25% by mass, particularly preferably 5 to 25% by mass, and most preferably 10 to 25% by mass based on the total solid content of the photosensitive resin composition. When the content of component (B1) is 0.5% by mass or more based on the total solid content of the photosensitive resin composition, the dielectric tangent tends to be sufficiently low, and when it is 40% by mass or less, the resolution of vias tends to be good.

[0074] ((Content of component (B)) Also, in the photosensitive resin composition of the present embodiment, the content of component (B) is preferably 1 to 30% by mass, more preferably 3 to 25% by mass, still more preferably 5 to 25% by mass, and particularly preferably 10 to 25% by mass based on the total solid content of the photosensitive resin composition from the viewpoints of adhesion strength to copper plating, insulation reliability, and heat resistance. Also, in the photosensitive resin composition of the present embodiment, the number of epoxy functional groups of the (B) epoxy resin is 1.3 to 2.3 times, preferably 1.3 to 2.0 times, more preferably 1.3 to 1.8 times, and still more preferably 1.4 to 1.6 times the number of acidic substituent groups of the “(A1) photopolymerizable compound having an acidic substituent group and an alicyclic skeleton together with an ethylenically unsaturated group”. If the number of epoxy functional groups of component (B) is 1.3 times or more the number of acidic substituent groups of component (A1), the desmear resistance will be excellent, and if it is 2.3 times or less, the low dielectric tangent will be excellent.

[0075] <(C) Photoinitiator> As component (C) used in the present embodiment, there is no particular limitation as long as it can polymerize the (A) component, and it can be appropriately selected from commonly used photoinitiators. Examples of component (C) include benzoins such as benzoin, benzoin methyl ether, and benzoin isopropyl ether; acetophenones such as acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, and N,N-dimethylaminoacetophenone; anthraquinones such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, and 2-aminoanthraquinone; thioxanthones such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, and 2,4-diisopropylthioxanthone; ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzophenones such as benzophenone, methylbenzophenone, 4,4'-dichlorobenzophenone, 4,4'-bis(diethylamino)benzophenone, Michler's ketone, and 4-benzoyl-4'-methyldiphenyl sulfide; acridines such as 9-phenylacridine and 1,7-bis(9,9'-acridinyl)heptane; acylphosphine oxides such as 2,4,6-trimethylbenzoyl diphenylphosphine oxide; oxime esters such as 1,2-octanedione-1-[4-(phenylthio)phenyl]-2-(O-benzoyloxime), 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone 1-(O-acetoxime), and 1-phenyl-1,2-propanedione-2-[O-(ethoxycarbonyl)oxime]. Among these, acetophenones, thioxanthones, and benzophenones are preferred, and 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, 2,4-diethylthioxanthone, and 4,4'-bis(diethylamino)benzophenone are more preferred.Acetophenones and benzophenones have the advantage of being difficult to volatilize and difficult to generate as outgases, and thioxanthones have the advantage of being capable of photocuring even in the visible light region. The component (C) may be used alone or in combination of two or more. When two or more are used in combination, it is preferable to use a combination of acetophenones, thioxanthones and benzophenones, and it is more preferable to use a combination of 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, 2,4-diethylthioxanthone and 4,4'-bis(diethylamino)benzophenone.

[0076] ((Content of component (C)) The content of the component (C) is not particularly limited, but based on the total solid content of the photosensitive resin composition, it is preferably 0.1 to 15% by mass, more preferably 0.15 to 5% by mass, still more preferably 0.2 to 1.5% by mass, particularly preferably 0.2 to 1.0% by mass, and most preferably 0.25 to 0.80% by mass. If the content of the component (C) is 0.1% by mass or more, there is a tendency to reduce the risk of the exposed site eluting during development in the interlayer insulating layer formed using the photosensitive resin composition, and if it is 15% by mass or less, there is a tendency for the heat resistance to improve.

[0077] <(C') Photoinitiator aid> The photosensitive resin composition of this embodiment may contain a (C') photoinitiator aid together with the above-mentioned component (C). Examples of the (C') photoinitiator aid include tertiary amines such as ethyl N,N-dimethylaminobenzoate, isoamyl N,N-dimethylaminobenzoate, pentyl 4-dimethylaminobenzoate, triethylamine, and triethanolamine. The component (C') may be used alone or in combination of two or more. When the photosensitive resin composition of the present embodiment contains the component (C'), its content is preferably 0.01 to 20% by mass, more preferably 0.2 to 5% by mass, still more preferably 0.3 to 2% by mass, based on the total amount of the resin components of the photosensitive resin composition. Note that the photosensitive resin composition of the present embodiment may not contain the component (C').

[0078] <(D) Elastomer> The photosensitive resin composition of the present embodiment may contain an elastomer as the component (D), and it is preferable to contain it. By containing the component (D), the photosensitive resin composition tends to be excellent in via resolution, adhesion strength to plated copper, and electrical insulation reliability. Further, the component (D) also has an effect of suppressing a decrease in flexibility and adhesion strength to plated copper caused by the strain (internal stress) inside the cured product due to the curing shrinkage of the component (A). As the component (D), an elastomer that is liquid at 25°C is preferable. The component (D) may be used alone or in combination of two or more.

[0079] Examples of the elastomer include styrene-based elastomers, olefin-based elastomers, polyester-based elastomers, urethane-based elastomers, polyamide-based elastomers, acrylic-based elastomers, silicone-based elastomers, etc., and it is preferable to use at least one selected from these. These elastomers are composed of a hard segment component and a soft segment component. The former tends to contribute to heat resistance and strength, and the latter tends to contribute to flexibility and toughness. As the component (D), among the above exemplifications, from the viewpoints of compatibility, solubility, and adhesion strength to electrodeposited copper, it preferably contains at least one selected from the group consisting of an olefin-based elastomer, a polyester-based elastomer, and a urethane-based elastomer, and more preferably contains a polyester-based elastomer. Further, it is more preferable that the component (D) is at least one selected from the group consisting of an olefin-based elastomer, a polyester-based elastomer, and a urethane-based elastomer, and particularly preferably an olefin-based elastomer.

[0080] (Styrene-based elastomer) Examples of the styrene-based elastomer include styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, styrene-ethylene-butylene-styrene block copolymer, styrene-ethylene-propylene-styrene block copolymer, and the like. The styrene-based elastomer may be used alone or in combination of two or more. Examples of the components constituting the styrene-based elastomer include styrene; styrene derivatives such as α-methylstyrene, 3-methylstyrene, 4-propylstyrene, 4-cyclohexylstyrene, and the like. As the styrene-based elastomer, those having a number average molecular weight of 1,000 to 50,000 are preferable, and those having a number average molecular weight of 3,000 to 20,000 are more preferable. In this specification, the number average molecular weight is a value determined by gel permeation chromatography (GPC) method using tetrahydrofuran as a solvent and converted to standard polystyrene.

[0081] Styrene-based elastomers can also use commercially available products. Commercially available products include Toughprene, Solprene T, Asaprene T, Tough Tech (all manufactured by Asahi Kasei Corporation, "Toughprene", "Asaprene", and "Tough Tech" are registered trademarks), Elastomer AR (manufactured by Aron Kasei Co., Ltd.), Clayton G, Hyperflex (all manufactured by Shell Japan Limited), JSR-TR, TSR-SIS, Dynaron (all manufactured by JSR Corporation), Denka STR (manufactured by Denka Co., Ltd.), Quintac (manufactured by Nippon Zeon Co., Ltd., "Quintac" is a registered trademark), TPE-SB series (manufactured by Sumitomo Chemical Co., Ltd.), Labaron (manufactured by Mitsubishi Chemical Corporation, "Labaron" is a registered trademark), Septon, Hybrar (all manufactured by Kuraray Co., Ltd., "Septon" and "Hybrar" are registered trademarks), Sumiflex (manufactured by Sumitomo Bakelite Co., Ltd.), Leostomer, Actimer (all manufactured by Riken Technos Co., Ltd., "Leostomer" and "Actimer" are registered trademarks), etc.

[0082] (Olefin-based elastomer) The olefin-based elastomer is, for example, a polymer or copolymer of α-olefins having 2 to 20 carbon atoms such as ethylene, propylene, 1-butene, 1-hexene, 4-methyl-pentene, etc. Note that the olefin-based elastomer may have a hydroxyl group at the molecular end, and it is preferably one having a hydroxyl group at the molecular end. The olefin-based elastomer may be used alone or in combination of two or more. Examples of the olefin-based elastomer include polyethylene, polybutadiene, hydroxyl group-containing polybutadiene, hydroxyl group-containing polyisopropylene, ethylene-propylene copolymer (EPR), ethylene-propylene-diene copolymer (EPDM), etc. are preferably mentioned. Also, copolymers of the α-olefins having 2 to 20 carbon atoms and non-conjugated dienes having 2 to 20 carbon atoms such as dicyclopentadiene, 1,4-hexadiene, cyclooctadiene, methylene norbornene, ethylidene norbornene, butadiene, isoprene, etc. are also mentioned. Furthermore, carboxy-modified NBR obtained by copolymerizing methacrylic acid with a butadiene-acrylonitrile copolymer is also mentioned. As the olefin-based elastomer, those having a number average molecular weight of 1,000 to 8,000 are preferred, and those having a number average molecular weight of 1,500 to 6,500 are more preferred.

[0083] Commercially available products may be used as the olefin-based elastomer. Examples of commercially available products include Mirastomer (trade name, manufactured by Mitsui Chemicals, Inc.), EXACT (trade name, manufactured by ExxonMobil), ENGAGE (trade name, manufactured by The Dow Chemical Company), Poly ip, Poly bd (trade name, manufactured by Idemitsu Kosan Co., Ltd.), hydrogenated styrene-butadiene rubber “DYNABON HSBR” (trade name, manufactured by JSR Corporation), butadiene-acrylonitrile copolymer “NBR series” (trade name, manufactured by JSR Corporation), “XER series” of carboxyl group-modified butadiene-acrylonitrile copolymer at both ends (trade name, manufactured by JSR Corporation), BF-1000 of epoxidized polybutadiene obtained by partially epoxidizing polybutadiene (trade name, manufactured by Nippon Soda Co., Ltd.), “Epolead series” (trade name, manufactured by Daicel Corporation), and the like.

[0084] (Polyester-based elastomer) Examples of the polyester-based elastomer include those obtained by polycondensing a dicarboxylic acid or its derivative and a diol compound or its derivative. The polyester-based elastomer may be used alone or in combination of two or more. Examples of the dicarboxylic acid include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid; aromatic dicarboxylic acids in which the hydrogen atoms of the aromatic ring of the aromatic dicarboxylic acid are substituted with a methyl group, an ethyl group, a phenyl group, etc.; aliphatic dicarboxylic acids having 2 to 20 carbon atoms such as adipic acid, sebacic acid, and dodecanedicarboxylic acid; alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid; and the like. From the viewpoint of adhesion to the base material, it is also preferable to use dimer acid derived from natural products as the dicarboxylic acid. The dicarboxylic acid may be used alone or in combination of two or more. Examples of the derivative of the dicarboxylic acid include anhydrides of the dicarboxylic acid.

[0085] Examples of the diol compound include aliphatic diols such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, and 1,10-decanediol; alicyclic diols such as 1,4-cyclohexanediol; and aromatic diols represented by the following general formula (D-1). The diol compound may be used alone or in combination of two or more.

[0086]

Chemical formula

[0087] In general formula (D-1), examples of the alkylene group having 1 to 10 carbon atoms represented by X D1 include a methylene group, 1,2-dimethylene group, 1,3-trimethylene group, 1,4-tetramethylene group, 1,5-pentamethylene group, and the like. From the viewpoints of via resolution, adhesion strength to plated copper, and electrical insulation reliability, an alkylene group having 1 to 3 carbon atoms is preferable, and a methylene group is more preferable. Examples of the alkylidene group having 2 to 10 carbon atoms represented by X D1 include an ethylidene group, propylidene group, isopropylidene group, butylidene group, isobutylidene group, pentylidene group, isopentylidene group, and the like. From the viewpoints of via resolution, adhesion strength to plated copper, and electrical insulation reliability, an isopropylidene group is preferable. Examples of the cycloalkylene group having 4 to 8 carbon atoms represented by X D1 include a cyclopentylene group, cyclohexylene group, cyclooctylene group, and the like. X D1 Among them, an alkylene group having 1 to 10 carbon atoms and an alkylidene group having 2 to 10 carbon atoms are preferable, and a methylene group and an isopropylidene group are more preferable.

[0088] In the general formula (D-1), R D1 and R D2 Examples of the halogen atom represented by include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like. R D1 and R D2 Examples of the alkyl group having 1 to 12 carbon atoms represented by include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group, an n-pentyl group, and the like. The alkyl group is preferably an alkyl group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and even more preferably a methyl group. p and q are each independently an integer of 0 to 4, and each is preferably 0 or 1. r is 0 or 1, and either is acceptable. When r is 0, the structure is represented by the following general formula (D-1’).

Chemical formula

[0089] Examples of the aromatic diol represented by the general formula (D-1) include bisphenol A, bis(4-hydroxyphenyl)methane, bis(4-hydroxy-3-methylphenyl)propane, resorcin, and the like.

[0090] Furthermore, as the polyester-based elastomer, a multi-block copolymer in which an aromatic polyester (for example, polybutylene terephthalate) portion is used as a hard segment component and an aliphatic polyester (for example, polytetramethylene glycol) portion is used as a soft segment component can also be used, and it is preferable to use such a multi-block copolymer. As such multi-block copolymers, there are various grades of commercially available products depending on the types, ratios, and molecular weights of the hard and soft segments. Specifically, "Hytrel (registered trademark)" (manufactured by Toray DuPont Co., Ltd.), "Pelprene (registered trademark)" (manufactured by Toyobo Co., Ltd.), "Esper (registered trademark)" (manufactured by Hitachi Chemical Co., Ltd.), etc. can be mentioned.

[0091] As the polyester-based elastomer, those having a number average molecular weight of 900 to 30,000 are preferable, those having a number average molecular weight of 1,000 to 25,000 are more preferable, and those having a number average molecular weight of 5,000 to 20,000 are even more preferable.

[0092] Commercially available products of polyester-based elastomers may be used. As commercially available products other than those mentioned above, for example, Teslac 2505-63 (manufactured by Hitachi Chemical Co., Ltd., "Teslac" is a registered trademark) etc. are commercially available.

[0093] (Urethane-based elastomer) As the urethane-based elastomer, for example, those containing a hard segment composed of a short-chain diol and a diisocyanate and a soft segment composed of a high molecular weight (long-chain) diol and a diisocyanate are preferably mentioned. The urethane-based elastomer may be used alone or in combination of two or more. Examples of the high molecular weight (long-chain) diol include polypropylene glycol, polytetramethylene oxide, poly(1,4-butylene adipate), poly(ethylene-1,4-butylene adipate), polycaprolactone, poly(1,6-hexylene carbonate), poly(1,6-hexylene-neopentylene adipate), etc. The number average molecular weight of the high molecular weight (long-chain) diol is preferably 500 to 10,000. Examples of the short-chain diol include ethylene glycol, propylene glycol, 1,4-butanediol, bisphenol A, etc. The number average molecular weight of the short-chain diol is preferably 48 to 500. As the urethane-based elastomer, those having a number average molecular weight of 1,000 to 25,000 are preferred, those having a number average molecular weight of 1,500 to 20,000 are more preferred, and those having a number average molecular weight of 2,000 to 15,000 are even more preferred.

[0094] Commercially available products may be used as the urethane-based elastomer. Examples of the commercially available products include Nipolan 3116 (manufactured by Toray Industries, Inc., "Nipolan" is a registered trademark), PANDEX T-2185, T-2983N (manufactured by DIC Corporation), Milactran series (manufactured by Nippon Milactran Co., Ltd., "Milactran" is a registered trademark), Hitaroid series (manufactured by Hitachi Chemical Co., Ltd., "Hitaroid" is a registered trademark), etc.

[0095] (Polyamide-based elastomer) The polyamide-based elastomer is roughly classified into two types: a polyether block amide type using polyamide for the hard segment and polyether for the soft segment; and a polyether ester block amide type using polyamide for the hard segment and polyester for the soft segment. Specific examples of the polyamide-based elastomer include block copolymers using polyamide as the hard segment component and polybutadiene, butadiene-acrylonitrile copolymer, styrene-butadiene copolymer, polyisoprene, ethylene-propylene copolymer, polyether, polyester, polybutadiene, polycarbonate, polyacrylate, polymethacrylate, polyurethane, silicone rubber, etc. as the soft segment component. The polyamide-based elastomer may be used alone or in combination of two or more. As the polyamide-based elastomer, those having a number average molecular weight of 1,000 to 50,000 are preferred, and those having a number average molecular weight of 2,000 to 30,000 are more preferred.

[0096] Polyamide-based elastomers may use commercially available products. Examples of commercially available products include UBE polyamide elastomers (manufactured by Ube Industries, Ltd.), Diamide (manufactured by Daicel-Evonik Co., Ltd., "Diamide" is a registered trademark), PEBAX (manufactured by Toray Industries, Inc.), Grilon ELY (manufactured by EMS Chemie Japan Co., Ltd., "Grilon" is a registered trademark), Novamid (manufactured by Mitsubishi Chemical Corporation), Grilax (manufactured by Toyobo Co., Ltd., "Grilax" is a registered trademark), and the like.

[0097] (Acrylic-based elastomer) Examples of the acrylic-based elastomer include polymers of raw material monomers mainly composed of acrylic esters. Preferred examples of the acrylic ester include ethyl acrylate, butyl acrylate, methoxyethyl acrylate, ethoxyethyl acrylate, and the like. Further, as the crosslinking point monomer, those copolymerized with glycidyl methacrylate, allyl glycidyl ether, etc. may be used, and those copolymerized with acrylonitrile, ethylene, etc. may also be used. Specifically, acrylonitrile-butyl acrylate copolymer, acrylonitrile-butyl acrylate-ethyl acrylate copolymer, acrylonitrile-butyl acrylate-glycidyl methacrylate copolymer, and the like can be mentioned. The acrylic-based elastomer may be used alone or in combination of two or more. The acrylic-based elastomer preferably has a number average molecular weight of 1,000 to 50,000, more preferably 2,000 to 30,000.

[0098] (Silicone-based elastomer) The silicone-based elastomer is an elastomer mainly composed of organopolysiloxane, and is classified into, for example, polydimethylsiloxane-based elastomer, polymethylphenylsiloxane-based elastomer, polydiphenylsiloxane-based elastomer, and the like. The silicone-based elastomer may be used alone or in combination of two or more. As the silicone-based elastomer, those having a number average molecular weight of 1,000 to 50,000 are preferred, and those having a number average molecular weight of 2,000 to 30,000 are more preferred.

[0099] Commercially available products may be used as the silicone-based elastomer. Examples of commercially available products include KE series (manufactured by Shin-Etsu Chemical Co., Ltd.), SE series, CY series, and SH series (all of the above are manufactured by Toray Dow Corning Co., Ltd.).

[0100] (Other elastomers) In addition, as the component (D), an embodiment containing at least one selected from the group consisting of polyphenylene ether resin, phenoxy resin, polycarbonate resin, polyamideimide resin, polyimide resin, xylene resin, polyphenylene sulfide resin, polyetherimide resin, polyetheretherketone resin, tetrafluoroethylene resin, polyacrylonitrile resin, maleic anhydride-modified polybutadiene, phenol-modified polybutadiene, and carboxy-modified polyacrylonitrile may also be used.

[0101] (Content of component (D)) When the photosensitive resin composition of this embodiment contains the component (D), its content is preferably 0.5 to 20% by mass, more preferably 1.0 to 20% by mass, still more preferably 1.0 to 15% by mass, particularly preferably 1.0 to 10% by mass, and most preferably 1.0 to 4% by mass based on the total solid content of the photosensitive resin composition. If the content of the component (D) is 0.5% by mass or more, the effect of improving the adhesion strength to copper plating is sufficient, and the electrical insulation reliability tends to be further improved. If the content of the component (D) is 20% by mass or less, the resolution of vias, the adhesion strength to copper plating, and the electrical insulation reliability tend to be sufficient together.

[0102] <(E) Inorganic filler> The photosensitive resin composition of this embodiment may contain an inorganic filler as component (E), and it is preferable to contain an inorganic filler. By containing an inorganic filler, the thermal expansion can be reduced, and the risk of warpage is decreased. In the thermosetting resin compositions that have been conventionally used as the interlayer insulating layer of multilayer printed wiring boards, the thermal expansion has been reduced by incorporating an inorganic filler. However, when an inorganic filler is incorporated into a photosensitive resin composition, it is difficult to achieve a reduction in thermal expansion by incorporating a large amount because the inorganic filler causes light scattering and becomes an obstacle to development. Thus, there are new problems unique to photosensitive resin compositions with respect to incorporating an inorganic filler. However, the photosensitive resin composition of this embodiment tends to have high resolution of vias even when a large amount of inorganic filler is incorporated. Therefore, with the photosensitive resin composition of this embodiment, it is possible to achieve both a reduction in thermal expansion and high resolution of vias.

[0103] (E) component, for example, includes silica (SiO 2 ), alumina (Al 2 O 3 ), titania (TiO 2 ), tantalum oxide (Ta 2 O 5 ), zirconia (ZrO 2 ), silicon nitride (Si 3 N 4 ), barium titanate (BaO·TiO 2 ), barium carbonate (BaCO 3 ), magnesium carbonate (MgCO 3 ), aluminum hydroxide (Al(OH) 3 ), magnesium hydroxide (Mg(OH) 2 ), lead titanate (PbO·TiO 2 ), lead zirconate titanate (PZT), lead lanthanum zirconate titanate (PLZT), gallium oxide (Ga 2 O 3 ), spinel (MgO·Al 2 O 3 ), mullite (3Al 2 O 3 ·2SiO 2 ), cordierite (2MgO·2Al2 O 3 / 5SiO 2 )、 talc (3MgO·4SiO 2 ·H 2 O), aluminum titanate (TiO 2 ·Al 2 O 3 ), yttria-containing zirconia (Y 2 O 3 ·ZrO 2 ), barium silicate (BaO·8SiO 2 ), boron nitride (BN), calcium carbonate (CaCO 3 ), barium sulfate (BaSO 4 ), calcium sulfate (CaSO 4 ), zinc oxide (ZnO), magnesium titanate (MgO·TiO 2 ), hydrotalcite, mica, calcined kaolin, carbon, etc. may be mentioned. Component (E) may be used alone or in combination of two or more.

[0104] (E) The average particle diameter of the component is preferably 0.01 to 5 μm, more preferably 0.1 to 3 μm, still more preferably 0.1 to 2 μm, and particularly preferably 0.1 to 1 μm from the viewpoint of via resolution. Further, an (E) component having a smaller particle diameter may be used in combination. The average particle diameter of such an (E) component is preferably 20 to 500 nm, more preferably 30 to 350 nm, still more preferably 50 to 300 nm, particularly preferably 80 to 300 nm, and most preferably 140 to 300 nm. Here, the average particle diameter of the (E) component is the volume average particle diameter of the inorganic filler in a state of being dispersed in the photosensitive resin composition, and is taken as the value obtained by measuring as follows. First, after diluting (or dissolving) the photosensitive resin composition 1,000-fold with methyl ethyl ketone, using a submicron particle analyzer (manufactured by Beckman Coulter, Inc., trade name: N5), in accordance with the international standard ISO13321, at a refractive index of 1.38, the particles dispersed in the solvent are measured, and the particle diameter at an integrated value of 50% (volume basis) in the particle size distribution is taken as the average particle diameter (volume average particle diameter). Also, for the (E) component contained in the photosensitive resin film provided on the carrier film and the interlayer insulating layer, after diluting (or dissolving) 1,000-fold (volume ratio) using a solvent as described above, it can be measured by using the above submicron particle analyzer.

[0105] As the (E) component, from the viewpoints of heat resistance and low thermal expansion, it preferably contains silica, and more preferably is silica. Further, from the viewpoint of improving the dispersibility of the inorganic filler in the photosensitive resin composition by the anti-aggregation effect, those surface-treated with alumina or an organic silane-based compound may be used.

[0106] (Content of the (E) component) When the photosensitive resin composition of this embodiment contains the component (E), its content is not particularly limited, but based on the total solid content of the photosensitive resin composition, it is preferably 5 to 75% by mass, more preferably 10 to 65% by mass, still more preferably 20 to 60% by mass, particularly preferably 30 to 55% by mass, and most preferably 40 to 50% by mass. If the content of the component (E) is within the above range, the mechanical strength, heat resistance, and resolution of vias can be improved.

[0107] <(F) Curing agent or curing accelerator> From the viewpoint of further improving various properties such as heat resistance and low dielectric tangent, it is preferable to contain a curing agent or a curing accelerator in the photosensitive resin composition of this embodiment. Examples of the component (F) include active ester curing agents; 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, m-phenylenediamine, m-xylenediamine, diaminodiphenylsulfone, dicyandiamide, urea, urea derivatives, melamine, and polybasic hydrazides; organic acid salts and / 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; tertiary amines such as trimethylamine, N,N-dimethyloctylamine, N-benzyldimethylamine, pyridine, N-methylmorpholine, hexa(N-methyl)melamine, 2,4,6-tris(dimethylaminophenol), tetramethylguanidine, and m-aminophenol; polyphenols such as polyvinylphenol, brominated polyvinylphenol, phenol novolac, and alkylphenol novolac; organic phosphines such as tributylphosphine, triphenylphosphine, and tris-2-cyanoethylphosphine; phosphonium salts such as tri-n-butyl(2,5-dihydroxyphenyl)phosphonium bromide and hexadecyltributylphosphonium chloride; quaternary ammonium salts such as benzyltrimethylammonium chloride and phenyltributylammonium chloride; the aforementioned polybasic acid anhydrides; diphenyliodonium tetrafluoroborate, triphenylsulfonium hexafluoroantimonate, 2,4,6-triphenylthiopyrylium hexafluorophosphate, and the like. Among these, imidazole derivatives are preferred, and 1-benzyl-2-phenylimidazole is more preferred, from the viewpoint of further improving various properties such as heat resistance and low dielectric tangent. In addition, in the present invention, an embodiment not containing an active ester curing agent is advantageous in that it has a low dielectric tangent. When the photosensitive resin composition of this embodiment contains the component (F), its content is preferably 0.01 to 20% by mass, more preferably 0.05 to 15% by mass, still more preferably 0.1 to 12% by mass, and particularly preferably 0.3 to 7% by mass based on the total amount of the resin components of the photosensitive resin composition.

[0108] <(G) Pigment> The photosensitive resin composition of this embodiment may contain a pigment as the component (G) according to the desired color for adjusting photosensitivity and the like. As the component (G), a colorant that develops the desired color may be appropriately selected and used. For example, known colorants such as phthalocyanine blue, phthalocyanine green, iodine green, diazo yellow, crystal violet, titanium oxide, carbon black, and naphthalene black are preferably mentioned.

[0109] ((Content of component (G))) When the photosensitive resin composition of this embodiment contains the component (G), its content is preferably 0.01 to 5% by mass, more preferably 0.03 to 3% by mass, and still more preferably 0.05 to 2% by mass based on the total solid content of the photosensitive resin composition from the viewpoint of adjusting photosensitivity and the like.

[0110] <(H) Thermosetting resin (excluding the above-mentioned (B) epoxy resin and the above-mentioned (F) component.)> The photosensitive resin composition of this embodiment may further contain a thermosetting resin (excluding the above-mentioned (B) epoxy resin and the above-mentioned (F) component.) from the viewpoints of adhesion strength to electroless copper, insulation reliability, and heat resistance. Examples of the thermosetting resin include phenol resin, unsaturated imide resin, cyanate resin, isocyanate resin, benzoxazine resin, oxetane resin, amino resin, unsaturated polyester resin, allyl resin, dicyclopentadiene resin, silicone resin, triazine resin, and melamine resin. Further, it is not particularly limited thereto, and known thermosetting resins can be used. (H) component may be used alone or in combination of two or more.

[0111] (Content of component (H)) When the photosensitive resin composition of this embodiment contains component (H), its content is preferably 1 to 30% by mass, more preferably 1 to 15% by mass, and still more preferably 1 to 10% by mass based on the total solid content of the photosensitive resin composition, from the viewpoints of adhesion strength to copper plating, insulation reliability, and heat resistance.

[0112] <Diluent> A diluent can be used in the photosensitive resin composition of this embodiment as needed. As the diluent, for example, organic solvents and the like can be used. Examples of organic solvents 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, propylene glycol monoethyl ether acetate, butyl cellosolve acetate, and carbitol acetate; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha. The diluent may be used alone or in combination of two or more.

[0113] (Content of diluent) The content of the diluent may be appropriately selected so that the concentration of the total solid content in the photosensitive resin composition is preferably 40 to 90% by mass, more preferably 50 to 80% by mass, and still more preferably 55 to 70% by mass. By adjusting the amount of the diluent used in this way, the coatability of the photosensitive resin composition is improved, and the formation of a higher definition pattern becomes possible.

[0114] (Other additives) In the photosensitive resin composition of this embodiment, if necessary, polymerization inhibitors such as hydroquinone, methylhydroquinone, hydroquinone monomethyl ether, catechol, pyrogallol, etc.; thickeners such as benton, montmorillonite, etc.; foam stabilizers such as silicone-based foam stabilizers, fluorine-based foam stabilizers, vinyl resin-based foam stabilizers, etc.; silane coupling agents; and various other known and commonly used additives can be contained. Furthermore, flame retardants such as brominated epoxy compounds, acid-modified brominated epoxy compounds, antimony compounds, and phosphate compounds of phosphorus-based compounds, aromatic condensed phosphoric acid esters, halogen-containing condensed phosphoric acid esters, etc. can be contained.

[0115] The photosensitive resin composition of this embodiment can be obtained by kneading and mixing each component with a roll mill, bead mill, etc. Here, the photosensitive resin composition of this embodiment may be used in a liquid state or in a film state. When used in a liquid state, the coating method of the photosensitive resin composition of this embodiment is not particularly limited, and examples include various coating methods such as printing methods, spin coating methods, spray coating methods, jet dispensing methods, inkjet methods, dip coating methods, etc. Among these, from the perspective of more easily forming the photosensitive layer, it may be appropriately selected from printing methods and spin coating methods. Also, when used in a film state, for example, it can be used in the form of the photosensitive resin film described later. In this case, a photosensitive layer with a desired thickness can be formed by laminating it on a carrier film using a laminator or the like. Note that using it in a film state is preferable because the manufacturing efficiency of multilayer printed wiring boards is higher.

[0116] [Photosensitive Resin Film, Photosensitive Resin Film for Interlayer Insulation Layer] The photosensitive resin film of this embodiment is a photosensitive layer that will later become an interlayer insulation layer and is composed of the photosensitive resin composition of this embodiment. The photosensitive resin film of this embodiment may be in a form in which a photosensitive resin film is provided on a carrier film. The thickness (after drying) of the photosensitive resin film (photosensitive layer) is not particularly limited, but from the perspective of thinning the multilayer printed wiring board, it is preferably 1 to 100 μm, more preferably 1 to 50 μm, and even more preferably 5 to 40 μm.

[0117] The photosensitive resin film of this embodiment can be obtained, for example, by applying and drying the photosensitive resin composition of this embodiment on a carrier film with a known coating device such as a comma coater, bar coater, kiss coater, roll coater, gravure coater, die coater, etc., to form a photosensitive layer that will later become an interlayer insulating layer. Examples of the carrier film include polyester films such as polyethylene terephthalate film and polybutylene terephthalate film; polyolefin films such as polypropylene film and polyethylene film. The thickness of the carrier film can be appropriately selected from the range of 5 to 100 μm, but is preferably 5 to 60 μm, and more preferably 15 to 45 μm.

[0118] In addition, for the photosensitive resin film of this embodiment, a protective film can also be provided on the surface of the photosensitive layer that is opposite to the surface in contact with the carrier film. As the protective film, for example, polymer films such as polyethylene and polypropylene can be used. Also, a polymer film similar to the above-mentioned carrier film may be used, or a different polymer film may be used.

[0119] For drying the coating film formed by applying the photosensitive resin composition, a hot air dryer, a dryer using far-infrared rays, or a dryer using near-infrared rays can be used. The drying temperature is preferably 60 to 150 °C, more preferably 70 to 120 °C, and even more preferably 80 to 100 °C. Also, the drying time is preferably 1 to 60 minutes, more preferably 2 to 30 minutes, and even more preferably 5 to 20 minutes. From the perspective of avoiding the diffusion of the diluent in the manufacturing process of the multilayer printed wiring board, the content of the residual diluent in the photosensitive resin film after drying is preferably 3% by mass or less, more preferably 2% by mass or less, and even more preferably 1% by mass or less.

[0120] The photosensitive resin film of this embodiment has good resolution of vias and a low dielectric tangent, so it is suitable as an interlayer insulating layer of a multilayer printed wiring board. That is, the present invention also provides a photosensitive resin film for an interlayer insulating layer. Note that the photosensitive resin film for an interlayer insulating layer can also be referred to as an interlayer insulating photosensitive film.

[0121] [Multilayer Printed Wiring Board and Method for Manufacturing the Same] The present invention also provides a multilayer printed wiring board containing an interlayer insulating layer formed using the photosensitive resin composition or photosensitive resin film of this embodiment. There is no particular limitation on the manufacturing method of the multilayer printed wiring board of this embodiment as long as it has a step of forming an interlayer insulating layer using the photosensitive resin composition of this embodiment. For example, it can be easily manufactured by the following method for manufacturing a multilayer printed wiring board of this embodiment.

[0122] Hereinafter, as an example of a preferred embodiment of the method for manufacturing a multilayer printed wiring board, a method for manufacturing a multilayer printed wiring board using the photosensitive resin film (photosensitive resin film for an interlayer insulating layer) of this embodiment will be described with appropriate reference to FIG. 1. The multilayer printed wiring board 100A can be manufactured, for example, by a manufacturing method including the following steps (1) to (4). Step (1): A step of laminating the photosensitive resin film of this embodiment on one or both sides of a circuit board (hereinafter referred to as "laminating step (1)"). Step (2): A step of forming an interlayer insulating layer having vias by exposing and developing the photosensitive resin film laminated in step (1) (hereinafter referred to as "photo via formation step (2)"). Step (3): A step of roughening the vias and the interlayer insulating layer (hereinafter referred to as "roughening treatment step (3)"). Step (4): A step of forming a circuit pattern on the interlayer insulating layer (hereinafter referred to as "circuit pattern formation step (4)").

[0123] (Laminating Step (1)) The laminating process (1) is a process of laminating the photosensitive resin film (photosensitive resin film for interlayer insulating layer) of the present embodiment on one or both sides of a circuit board (substrate 101 having a circuit pattern 102) using a vacuum laminator. Examples of the vacuum laminator include a vacuum applicator manufactured by Nichigo-Morton Co., Ltd., a vacuum pressure type laminator manufactured by Meiki Seisakusho Co., Ltd., a roll type dry coater manufactured by Hitachi, Ltd., and a vacuum laminator manufactured by Hitachi Chemical Electronics Co., Ltd.

[0124] When a protective film is provided on the photosensitive resin film, after peeling or removing the protective film, it can be laminated by pressure-bonding to the circuit board while applying pressure and heat so that the photosensitive resin film is in contact with the circuit board. This lamination can be carried out, for example, after preheating the photosensitive resin film and the circuit board as necessary, under reduced pressure with a pressure-bonding temperature of 70 to 130°C, a pressure-bonding pressure of 0.1 to 1.0 MPa, and an air pressure of 20 mmHg (26.7 hPa) or less, but it is not particularly limited to these conditions. Also, the lamination method may be a batch type or a continuous type using a roll. Finally, the photosensitive resin film laminated on the circuit board (hereinafter sometimes referred to as a photosensitive layer) is cooled to near room temperature to form an interlayer insulating layer 103. The carrier film may be peeled off here, or it may be peeled off after exposure as described later.

[0125] (Photo via formation process (2)) In the photo via formation step (2), at least a part of the photosensitive resin film laminated on the circuit board is exposed and then developed. By the exposure, the portion irradiated with the actinic rays is photocured to form a pattern. There is no particular limitation on the exposure method. For example, a method of irradiating the actinic rays in an image shape through a negative or positive mask pattern called an artwork (mask exposure method) may be adopted, or a method of irradiating the actinic rays in an image shape by a direct drawing exposure method such as an LDI (Laser Direct Imaging) exposure method or a DLP (Digital Light Processing) exposure method may be adopted. As the light source of the actinic rays, a known light source can be used. Specifically, as the light source, gas lasers such as carbon arc lamps, mercury vapor arc lamps, high-pressure mercury lamps, xenon lamps, and argon lasers; solid lasers such as YAG lasers; those that effectively emit ultraviolet rays or visible rays such as semiconductor lasers; and the like can be mentioned. The exposure amount is appropriately selected according to the light source used, the thickness of the photosensitive layer, etc. For example, in the case of ultraviolet irradiation from a high-pressure mercury lamp, when the thickness of the photosensitive layer is 1 to 100 μm, usually, 10 to 1,000 mJ / cm 2 is preferable, and 15 to 500 mJ / cm 2 is more preferable.

[0126] In development, the uncured portion of the photosensitive layer is removed from the substrate, whereby an interlayer insulating layer made of a photocured cured product is formed on the substrate. When a carrier film exists on the photosensitive layer, the carrier film is removed and then the unexposed portion is removed (developed). The development methods include wet development and dry development, and either can be adopted. However, wet development is widely used, and wet development can also be adopted in this embodiment. In the case of wet development, development is carried out by a known development method using a developer corresponding to the photosensitive resin composition. Examples of the development method include methods using a dip method, a paddle method, a spray method, brushing, slapping, scraping, rocking immersion, etc. Among these, from the viewpoint of improving the resolution of vias, the spray method is preferable, and among the spray methods, the high-pressure spray method is more preferable. Development may be carried out by one method, or may be carried out in combination of two or more methods. The composition of the developer is appropriately selected according to the composition of the photosensitive resin composition. For example, an alkaline aqueous solution, an aqueous developer, and an organic solvent-based developer can be mentioned, and among these, an alkaline aqueous solution is preferable.

[0127] In the photovia formation step (2), after exposure and development, post-UV curing with an exposure amount of about 0.2 to 10 J / cm 2 (preferably 0.5 to 5 J / cm 2 ) and post-thermal curing at a temperature of about 60 to 250 °C (preferably 120 to 200 °C) may be carried out as necessary to further cure the interlayer insulating layer, and it is preferable to do so. As described above, an interlayer insulating layer having vias 104 is formed. There is no particular limitation on the shape of the vias. Explaining in terms of the cross-sectional shape, for example, a square, an inverted trapezoid (the upper side is longer than the lower side), etc. can be mentioned. Explaining in terms of the shape seen from the front (the direction in which the via bottom can be seen), a circle, a square, etc. can be mentioned. In the formation of vias by the photolithography method in this embodiment, vias having a cross-sectional shape of an inverted trapezoid (the upper side is longer than the lower side) can be formed. In this case, it is preferable because the wrap-around property to the via wall surface of the plated copper is high.

[0128] The size (diameter) of the vias formed by this step can be 60 μm or less, and further, it can be less than 40 μm or 30 μm or less, and tends to be smaller than the size of vias produced by laser processing. There is no particular limitation on the lower limit value of the size (diameter) of the vias formed by this step, but it may be 15 μm or more, or may be 20 μm or more. However, the size (diameter) of the vias formed by this process is not necessarily limited to 60 μm or less. For example, it may be about 200 μm or less, and can be arbitrarily selected within the range of, for example, 15 to 300 μm.

[0129] (Roughening treatment step (3)) In the roughening treatment step (3), the surfaces of the vias and the interlayer insulating layer are roughened with a roughening solution. When smearing occurs in the photovia formation step (2), the smear may be removed with the roughening solution. The roughening treatment and the removal of the smear can be performed simultaneously. Examples of the roughening solution include a chromium / sulfuric acid roughening solution, an alkaline permanganic acid roughening solution (for example, a sodium permanganate roughening solution, etc.), and a sodium fluoride / chromium / sulfuric acid roughening solution. By the roughening treatment, an anchor with irregularities is formed on the surfaces of the vias and the interlayer insulating layer.

[0130] (Circuit pattern formation step (4)) The circuit pattern formation step (4) is a step of forming a circuit pattern on the interlayer insulating layer after the roughening treatment step (3). From the viewpoint of forming fine wiring, it is preferable to form the circuit pattern by a semi-additive process. Conductivity of the vias is achieved together with the formation of the circuit pattern by the semi-additive process. In the semi-additive process, first, after the roughening treatment step (3), electroless copper plating treatment is performed using a palladium catalyst or the like on the entire surface of the via bottom, via wall surface, and interlayer insulating layer to form a seed layer 105. The seed layer is for forming a power supply layer for performing electrolytic copper plating, and is preferably formed to have a thickness of about 0.1 to 2.0 μm. If the thickness of the seed layer is 0.1 μm or more, the connection reliability during electrolytic copper plating can be suppressed from decreasing. If it is 2.0 μm or less, it is not necessary to increase the etching amount when flash etching the seed layer between the wirings, and the damage to the wirings during etching can be suppressed.

[0131] The electroless copper plating process is carried out by depositing metallic copper on the surfaces of vias and interlayer insulating layers through the reaction between copper ions and a reducing agent. The electroless plating process and the electrolytic plating process may be well-known processes and are not particularly limited. However, the catalyst for the electroless plating process is preferably a palladium-tin mixed catalyst, and the primary particle size of the catalyst is preferably 10 nm or less. Also, as the plating composition for the electroless plating process, it is preferable to contain hypophosphorous acid as a reducing agent. Commercially available products can be used as the electroless copper plating solution. Examples of commercially available products include "MSK-DK" manufactured by Atotech Japan Co., Ltd., "Surcup (registered trademark) PEA ver.4" series manufactured by Uemura Kogyo Co., Ltd., and the like.

[0132] After the electroless copper plating process, a dry film resist is thermocompression-bonded onto the electroless copper plating using a roll laminator. The thickness of the dry film resist must be higher than the wiring height after electroplating copper. From this perspective, a dry film resist with a thickness of 5 - 30 μm is preferable. As the dry film resist, the "Fotec" series manufactured by Hitachi Chemical Co., Ltd., and the like are used. After the thermocompression bonding of the dry film resist, for example, the dry film resist is exposed through a mask on which a desired wiring pattern is drawn. The exposure can be performed using the same apparatus and light source as those that can be used when forming vias in the photosensitive resin film. After exposure, the carrier film on the dry film resist is peeled off, and development is performed using an alkaline aqueous solution to remove the unexposed portions and form a resist pattern 106. After that, an operation of removing the development residue of the dry film resist using plasma or the like may be performed as necessary. After development, electroplating copper is performed to form a copper circuit layer 107 and fill the vias.

[0133] After electrolytic copper plating, the dry film resist is removed using an alkaline aqueous solution or an amine-based stripper. After removing the dry film resist, the seed layer between the wirings is removed (flash etching). The flash etching is performed using an acidic solution such as sulfuric acid and hydrogen peroxide and an oxidizing solution. Specifically, "SAC" manufactured by JCU Corporation, "CPE-800" manufactured by Mitsubishi Gas Chemical Company, Inc., etc. are mentioned. After flash etching, if necessary, removal of palladium or the like attached to the portion between the wirings is performed. The removal of palladium can preferably be performed using an acidic solution such as nitric acid and hydrochloric acid.

[0134] After removing the dry film resist or after the flash etching step, preferably a post-bake treatment is performed. The post-bake treatment sufficiently thermosets the unreacted thermosetting components, and thereby further improves the electrical insulation reliability, curing characteristics, and adhesion strength to the plated copper. The thermosetting conditions vary depending on the type of the resin composition and the like, but the curing temperature is preferably 150 to 240°C and the curing time is preferably 15 to 100 minutes. By the post-bake treatment, one manufacturing process of a printed wiring board by the photo via method is completed, but the substrate is manufactured by repeating this process according to the required number of interlayer insulating layers. And preferably, a solder resist layer 108 is formed on the outermost layer.

[0135] As described above, the method for manufacturing a multilayer printed wiring board in which vias are formed using the photosensitive resin composition of the present embodiment has been described. Since the photosensitive resin composition of the present embodiment also has good pattern resolution, it is also suitable for forming, for example, a cavity for incorporating a chip or a passive element. The cavity can be suitably formed, for example, in the description of the multilayer printed wiring board above, by setting the drawing pattern when exposing the photosensitive resin film to form a pattern to be one that can form a desired cavity. Furthermore, the photosensitive resin composition of the present embodiment is also useful as a surface protective film such as a solder resist.

[0136] [Semiconductor Package] The present invention also provides a semiconductor package in which a semiconductor element is mounted on the multilayer printed wiring board of the present embodiment. The semiconductor package of the present embodiment can be manufactured by mounting a semiconductor element such as a semiconductor chip or a memory on a predetermined position of the multilayer printed wiring board of the present invention and encapsulating the semiconductor element with an encapsulating resin or the like.

Example

[0137] Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. Note that the properties of the photosensitive resin compositions obtained in each example were evaluated by the following methods.

[0138] [1. Evaluation of dielectric tangent] The protective films were peeled off from the carrier films and the photosensitive resin films with protective films manufactured in each example. Next, another photosensitive resin film was prepared and placed so that the exposed photosensitive resin films were in contact with each other, and then a laminating process was performed using a press-type vacuum laminator (manufactured by Meiki Seisakusho Co., Ltd., product name "MVLP-500"). The laminating conditions were a press hot plate temperature of 75°C, a vacuum drawing time of 20 seconds, a laminating press time of 20 seconds, an air pressure of 4 kPa or less, and a crimping pressure of 0.4 MPa. After the laminating process, the sample was left at room temperature for 1 hour or more to obtain a laminated body for evaluation in which the photosensitive resin film was sandwiched between carrier films.

[0139] Next, with respect to the obtained laminated body for evaluation, using a parallel light exposure machine (manufactured by OAK Corporation, product name "EXM-1201") with an ultra-high pressure mercury lamp as a light source, full-surface exposure was performed at 400 mJ / cm 2 Then, exposure was performed using an ultraviolet exposure device at an exposure amount of 2,000 mJ / cm 2 and heated at 170°C for 1 hour to obtain a cured film. Regarding the above-mentioned cured film, the dielectric tangent at 10 GHz was measured by the cavity resonator method. The measuring instruments used were the vector network analyzer E8364B manufactured by Agilent Technologies, Inc., the CP531 (10 GHz resonator) and CPMA-V2 (program) manufactured by Kanto Electronic Application Development Co., Ltd., respectively, and the measurements were carried out at an ambient temperature of 25°C. The dielectric tangent is preferably 0.0099 or less.

[0140] [2. Evaluation of desmear resistance] An evaluation laminate was obtained in the same manner as in [1. Evaluation of dielectric tangent]. Next, the obtained evaluation laminate was immersed in the swelling liquid "Swelling Dip Securigant P" (a glycol ether, an aqueous solution of sodium hydroxide, manufactured by Atotech Japan Co., Ltd.) at 70°C for 10 minutes, and then the evaluation laminate was washed with water at 25°C for 3 minutes. Next, it was immersed in the roughening liquid "Concentrate Compact P" (an aqueous solution of KMnO 4 : 60 g / L, NaOH: 40 g / L, manufactured by Atotech Japan Co., Ltd.) at 80°C for 15 minutes, and then the evaluation laminate was washed with water at 50°C for 1 minute. Finally, it was immersed in the neutralizing liquid "Reduction Solution Securigant P" (an aqueous solution of sulfuric acid, manufactured by Atotech Japan Co., Ltd.) at 40°C for 5 minutes, and then the evaluation laminate was washed with water at 25°C for 3 minutes. Thereafter, it was dried at 105°C for 10 minutes. The desmear treatment was performed as described above. The weight loss amount (g / m 2 ) after the desmear treatment with respect to the dry weight before the desmear treatment was calculated and used as an index of desmear resistance. The smaller the weight loss amount after the desmear treatment, the better the desmear resistance.

[0141] <Comparative Examples 1 to 5, Reference Example 1> (Preparation of photosensitive resin composition) The composition was formulated according to the formulation composition and formulation amounts shown in Table 1, and a photosensitive resin composition with a solid content concentration of 65% by mass was prepared using methyl ethyl ketone as a diluent. (Production of photosensitive resin film) A polyethylene terephthalate film with a thickness of 25 μm (HPE, manufactured by Teijin DuPont, trade name) was used as the carrier film. On this carrier film, the photosensitive resin composition prepared in each example was applied so that the film thickness after drying would be 25 μm, and it was dried at 100 °C for 10 minutes using a hot air convection dryer to form a photosensitive resin film (photosensitive layer). Subsequently, a biaxially stretched polypropylene film (MA-411, manufactured by Oji F-Tex Corporation, trade name) was laminated as a protective film on the surface of the photosensitive resin film (photosensitive layer) opposite to the side in contact with the carrier film, and a photosensitive resin film with the carrier film and the protective film laminated was produced. Using the produced photosensitive resin film, each evaluation was carried out according to the above method. The results are shown in Table 1.

[0142]

Table 1

[0143] Each component used in each example is as follows. (A) component; · A photopolymerizable compound having an acidic substituent and an alicyclic skeleton together with an ethylenically unsaturated group: "ZXR-1807H" (manufactured by Nippon Kayaku Co., Ltd., trade name) [(A1) component] · Dipentaerythritol pentaacrylate [(Aiii) component] (B) component; · An epoxy resin having a condensed aromatic ring: A naphthol type epoxy resin "Epoto (registered trademark) ESN-475V" (manufactured by Nippon Steel Chemical & Material Co., Ltd., trade name), corresponding to the epoxy resin represented by the general formula (II) [(B1) component] · A bisphenol-based epoxy resin: "YSLV-80XY", a bisphenol F type epoxy resin (manufactured by Nippon Steel Chemical & Material Co., Ltd., trade name) [(B2) component] · A biphenyl type epoxy resin: "NC-3000-L" (manufactured by Nippon Kayaku Co., Ltd., trade name) [(B2) component] · Epoxy resin "YL9057"; a polyfunctional novolac-type epoxy resin, manufactured by Mitsubishi Chemical Corporation, trade name, [(B2) component] · Epoxy resin "YL9058"; manufactured by Mitsubishi Chemical Corporation, trade name, [(B2) component] · Aliphatic chain epoxy resin: "FOLDI-E201" (manufactured by Nissan Chemical Industries, Ltd., trade name), a branched alkyl chain epoxy resin, [(B2) component] (C) component; · Photoinitiator 1: 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, acetophenones · Photoinitiator 2: 2,4-diethylthioxanthone, thioxanthones · Photoinitiator 3: 4,4'-bis(diethylamino)benzophenone, benzophenones (D) component; · Elastomer: "Epolead (registered trademark) PB3600" (manufactured by Daicel Corporation, trade name), epoxidized polybutadiene (E) component; · Silica 1: "SC-2050-LNF" (manufactured by Admatechs Co., Ltd., average particle size 0.5 μm, trade name) · Silica 2: "KC180G-LJA" (manufactured by Admatechs Co., Ltd., average particle size 180 nm, trade name) (F) component; · Curing agent or curing accelerator 1: "EXB-8" (manufactured by DIC Corporation, trade name), an active ester-based curing agent · Curing agent or curing accelerator 2: "Phenolite (registered trademark) LA-7052" (manufactured by DIC Corporation, trade name), a curing agent · Curing agent or curing accelerator 3: Isocyanate masked imidazole "G8009L" (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., trade name), a curing accelerator

[0144] From Table 1, in Reference Example 1, a lower dielectric tangent was obtained than in Comparative Examples 1 to 4, and better desmear resistance was also exhibited than in Comparative Examples 1 to 5. However, it was desirable to further improve the desmear resistance. Therefore, the inventors of the present invention conducted further investigations and, as shown below, by adjusting the epoxy functional group number of the component (B) to a predetermined range with respect to the number of acidic substituents of the component (A1), they succeeded in significantly improving the desmear resistance while having a low dielectric tangent.

[0145] <Reference Example 2, Examples 1 to 3> (Preparation of photosensitive resin composition) The composition was formulated according to the formulation composition and formulation amounts shown in Table 2, and a photosensitive resin composition with a solid content concentration of 65% by mass was prepared using methyl ethyl ketone as a diluent. (Production of photosensitive resin film) A polyethylene terephthalate film with a thickness of 25 μm (HPE, manufactured by Teijin DuPont, trade name) was used as a carrier film. On this carrier film, the photosensitive resin composition prepared in each example was applied so that the film thickness after drying would be 25 μm, and it was dried at 100 °C for 10 minutes using a hot air convection dryer to form a photosensitive resin film (photosensitive layer). Subsequently, a biaxially stretched polypropylene film (MA-411, manufactured by Oji Fibrex Co., Ltd., trade name) was laminated as a protective film on the surface of the photosensitive resin film (photosensitive layer) opposite to the side in contact with the carrier film, and a photosensitive resin film with the carrier film and the protective film laminated was produced. The produced photosensitive resin film was exposed using a stepper exposure apparatus "UX-2240" (manufactured by Ushio Electric Inc.). After exposure, it was left at room temperature for 30 minutes, and then the unexposed part of the photosensitive resin composition was spray-developed for 60 seconds using a 1% by mass aqueous sodium carbonate solution at 30 °C. As a result, the opening of the via could be confirmed, and it was found that the resolution of the via was also good. On the other hand, using the produced photosensitive resin film, each evaluation was also carried out according to the above method. The results are shown in Table 2.

[0146]

Table 2

[0147] Each component in Table 2 is the same as that in Table 1.

[0148] In Examples 1 to 3, good via resolution was achieved. Moreover, from Table 2, a low dielectric tangent was obtained. At the same time, the desmear resistance was significantly improved compared to Reference Example 2 where the number of epoxy functional groups in the (B) component was 1.0 times the number of acidic substituent groups in the (A1) component.

Explanation of Symbols

[0149] 100A Multilayer Printed Wiring Board 102 Circuit Pattern 103 Interlayer Insulating Layer 104 Via (Via Hole) 105 Seed Layer 106 Resist Pattern 107 Copper Circuit Layer 108 Solder Resist Layer

Claims

Claim 1 A photosensitive resin composition containing (A) a photopolymerizable compound having an ethylenically unsaturated group, (B) an epoxy resin, (C) a photopolymerization initiator, and (E) an inorganic filler, wherein the (A) photopolymerizable compound having an ethylenically unsaturated group includes (A1) a photopolymerizable compound having an acidic substituent and an alicyclic skeleton together with the ethylenically unsaturated group, and the (A1) component is obtained by reacting (a1) an alicyclic skeleton-containing epoxy resin with (a2) an ethylenically unsaturated group-containing organic acid to form a compound, and then reacting (a3) a polybasic acid anhydride containing a saturated group or an unsaturated group, and is (A1-1) an acid-modified ethylenically unsaturated group and an alicyclic skeleton-containing epoxy derivative, and the (a1) component is an epoxy resin represented by the following general formula (a1-1) or an epoxy resin having a structural unit represented by the following general formula (a1-2), wherein the (B) epoxy resin includes (B1) an epoxy resin having a condensed aromatic ring, and the (B1) component is an epoxy resin represented by the following general formula (II), and the content of the (A) photopolymerizable compound having an ethylenically unsaturated group is 15% by mass or more based on the total solid content of the photosensitive resin composition, and the content ratio of the (A1) component to the total amount of the (A) component is 55% by mass or more, the content of the (B1) epoxy resin containing a condensed aromatic ring is 10% by mass or more based on the total solid content of the photosensitive resin composition, the content of the (E) inorganic filler is 40% by mass or more based on the total solid content of the photosensitive resin composition, and the epoxy functional group number of the (B) component is 1.3 to 2.3 times the number of acidic substituents of the (A1) component. A photosensitive resin composition. 【Chemical 1】 (In general formula (a1-1), R Ａ１ R represents an alkyl group having 1 to 12 carbon atoms, and may be substituted anywhere in the alicyclic skeleton. Ａ２ represents an alkyl group having 1 to 12 carbon atoms. １ is an integer from 0 to 6, m ２ is an integer from 0 to 3. n is an integer from 0 to 10. [Chemical Formula 2] (In the general formula (a1-2), R Ａ１ represents an alkyl group having 1 to 12 carbon atoms, and may be substituted anywhere in the above alicyclic skeleton. m １ is an integer of 0 to 6.) 【Chemical Formula 3】 (In general formula (II), n ２ represents an integer from 1 to 10.) Claim 2 The photosensitive resin composition according to claim 1, wherein the (B) component includes (B2) an epoxy resin other than the (B1) component. Claim 3 The photosensitive resin composition according to claim 2, wherein the (B2) component is at least one selected from the group consisting of a biphenyl type epoxy resin, a biphenyl aralkyl type epoxy resin, a bisphenol type epoxy resin, and an alicyclic skeleton-containing epoxy resin. Claim 4 The photosensitive resin composition according to claim 2 or 3, wherein the content ratio of the (B1) component in the (B) component is 5% by mass or more. Claim 5 The photosensitive resin composition according to any one of claims 1 to 4, further containing (D) an elastomer. Claim 6 Furthermore, the photosensitive resin composition according to any one of claims 1 to 5, which contains a curing agent or a curing accelerator (F).

7. A photosensitive resin composition for forming a photvia, which is composed of the photosensitive resin composition according to any one of claims 1 to 6.

8. A photosensitive resin composition for an interlayer insulating layer, which is composed of the photosensitive resin composition according to any one of claims 1 to 6.

9. A photosensitive resin film, which is composed of the photosensitive resin composition according to any one of claims 1 to 6.

10. A photosensitive resin film for an interlayer insulating layer, which is composed of the photosensitive resin composition according to any one of claims 1 to 6.

11. A multilayer printed wiring board containing an interlayer insulating layer formed by using the photosensitive resin composition according to any one of claims 1 to 6.

12. A multilayer printed wiring board containing an interlayer insulating layer formed by using the photosensitive resin film according to claim 9.

13. A semiconductor package obtained by mounting a semiconductor element on the multilayer printed wiring board according to claim 11 or 12.

14. A method for manufacturing a multilayer printed wiring board, which includes the following steps (1) to (4). Step (1): A step of laminating the photosensitive resin film according to claim 9 on one or both sides of a circuit board. Step (2): A step of forming an interlayer insulating layer having vias by exposing and developing the photosensitive resin film laminated in the step (1). Step (3): A step of roughening the vias and the interlayer insulating layer. Step (4): A step of forming a circuit pattern on the interlayer insulating layer.

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