Photosensitive multi-layered resin film, printed wiring board, semiconductor package, and production method of printed wiring board

Abstract

To provide: a photosensitive multi-layered resin film which is excellent in storage stability and adhesiveness to a conductor; a printed wiring board using the photosensitive multi-layered resin film and a production method of the same; and a semiconductor package.SOLUTION: Provided is a photosensitive multi-layered resin film having a first resin composition layer and a second resin composition layer. Each of the first resin composition layer and the second resin composition layer contains (A) a compound having an ethylenically unsaturated group, (B) a thermosetting resin and (C) a photoinitiator. The second resin composition layer further contains (D) an imidazole compound. The content of (D) the imidazole compound in the first resin composition layer is 0-0.4 mass%, and the mass-based content of (D) the imidazole compound in the first resin composition layer is less than the mass-based content of (D) the imidazole compound in the second resin composition layer. Also provided are a printed wiring board using the photosensitive multi-layered resin film, a production method thereof, and a semiconductor package.SELECTED DRAWING: None

Description

[Technical field]

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

[0002] In recent years, electronic devices have become smaller and more powerful, and printed wiring boards are becoming increasingly dense due to an increase in the number of circuit layers and finer wiring. In particular, the density of semiconductor packages such as BGA (ball grid array) and CSP (chip size package) on which semiconductor chips are mounted is increasing significantly. For this reason, in addition to finer wiring, printed wiring boards are required to have thinner interlayer insulating layers and smaller diameter vias for interlayer connection.

[0003] A conventional method for manufacturing a multilayer printed wiring board is a build-up method (see, for example, Patent Document 1) in which an interlayer insulating layer and a conductor circuit layer are sequentially laminated to form the multilayer printed wiring board. As circuits become finer, the semi-additive method in which the circuits are formed by plating has become mainstream for multilayer printed wiring boards. In the conventional semi-additive method, a thermosetting resin film has been used to form the interlayer insulating layer.

[0004] Laser processing is the mainstream method for forming vias in an interlayer insulating layer formed from a thermosetting resin film. However, the reduction in the diameter of vias by laser processing is reaching its limit. In addition, when forming vias by laser processing, each via hole needs to be formed one by one. Therefore, when it is necessary to form a large number of vias to increase density, it takes a long time to form the vias, which results in high manufacturing costs and poor manufacturing efficiency.

[0005] Under these circumstances, a method has been proposed in which a plurality of small-diameter vias are formed at once by a photolithography method using a photosensitive resin film (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 7-304931 [Patent Document 2] JP 2017-116652 A Summary of the Invention [Problem to be solved by the invention]

[0007] In recent years, due to environmental concerns, the mounting of electronic components using lead-free solder has been put into practical use. Lead-free solder has a higher operating temperature than eutectic solder, so the materials for printed wiring boards require high heat resistance. In particular, when a printed wiring board is multi-layered, the interlayer insulating layer is subjected to multiple heat treatments, so higher heat resistance is required.

[0008] In the technology for forming an interlayer insulating layer using a photosensitive resin film, a method of blending a thermosetting resin and a curing accelerator has been investigated in order to increase the heat resistance of the interlayer insulating layer to be formed. However, according to the study by the present inventors, the reaction of a photosensitive resin film containing a thermosetting resin and a curing accelerator proceeds little by little at room temperature, and the developability may deteriorate. Therefore, there are problems with handling, such as the need to store the photosensitive resin film in a freezer. On the other hand, if a curing accelerator is not used to suppress the reaction of the thermosetting resin, the formed interlayer insulating layer has a problem of insufficient adhesive strength with plated copper (hereinafter also referred to as "conductor adhesion").

[0009] In view of the current situation, an objective of the present embodiment is to provide a photosensitive multilayer resin film having excellent storage stability and adhesion to a conductor, a printed wiring board using the photosensitive multilayer resin film and a method for manufacturing the same, and a semiconductor package. [Means for solving the problem]

[0010] As a result of investigations aimed at solving the above problems, the present inventors have found that the above problems can be solved by the present embodiment described below. That is, the present embodiment relates to the following [1] to

[11] . [1] A photosensitive multilayer resin film having a first resin composition layer and a second resin composition layer, The first resin composition layer and the second resin composition layer each include (A) a compound having an ethylenically unsaturated group, (B) a thermosetting resin, and (C) a photopolymerization initiator, The second resin composition layer further contains (D) an imidazole compound, The content of the imidazole compound (D) in the first resin composition layer is 0 to 0.4% by mass, A photosensitive multilayer resin film, wherein the content by mass of the imidazole compound (D) in the first resin composition layer is less than the content by mass of the imidazole compound (D) in the second resin composition layer. [2] The photosensitive multilayer resin film according to the above [1], wherein the content of the imidazole compound (D) in the second resin composition layer is 0.1 to 5 mass %. [3] The photosensitive multilayer resin film according to the above [1] or [2], wherein the first resin composition layer and the second resin composition layer each contain, as the (A) compound having an ethylenically unsaturated group, (A1) a compound having an ethylenically unsaturated group and an acidic substituent. [4] The photosensitive multilayer resin film according to any one of the above [1] to [3], wherein the first resin composition layer and the second resin composition layer each contain, as the (B) thermosetting resin, one or more resins selected from the group consisting of epoxy resins, maleimide resins, allyl resins, and vinyl resins. [5] The photosensitive multilayer resin film according to any one of the above [1] to [4], wherein the first resin composition layer and the second resin composition layer each contain an epoxy resin as the (B) thermosetting resin, and the content of the epoxy resin in the first resin composition layer on a mass basis is greater than the content of the epoxy resin in the second resin composition layer on a mass basis. [6] (I) The photosensitive multilayer resin film according to any one of the above [1] to [5], wherein the content of the fluorine-containing resin is 10 mass % or less based on the total amount of resin components in the photosensitive multilayer resin film. [7] The photosensitive multilayer resin film according to any one of the above [1] to [6], wherein the layer obtained by curing the first resin composition layer is a layer on which a circuit pattern is formed by copper plating, and the second resin composition layer is a layer having a surface to be attached when laminating the photosensitive multilayer resin film. [8] The photosensitive multilayer resin film according to any one of the above [1] to [7], which is used for forming an interlayer insulating layer having a photovia. [9] A printed wiring board having an interlayer insulating layer which is a cured product of the photosensitive multilayer resin film described in any one of [1] to [8] above.

[10] A semiconductor package having the printed wiring board described in [9] above.

[11] A method for producing a printed wiring board, comprising the following (1) to (4): (1): The photosensitive multilayer resin film according to any one of the above [1] to [8] is laminated onto one or both sides of a circuit board, with the second resin composition layer serving as an attachment surface. (2): Forming an interlayer insulating layer having vias by exposing and developing the photosensitive multilayer resin film laminated in (1) above. (3): Heat-curing the interlayer insulating layer having the vias. (4): Forming a circuit pattern on the layer obtained by curing the first resin composition layer of the interlayer insulating layer. Effect of the Invention

[0011] According to the present embodiment, it is possible to provide a photosensitive multilayer resin film having excellent storage stability and adhesion to a conductor, a printed wiring board using the photosensitive multilayer resin film and a method for producing the same, and a semiconductor package. [Brief description of the drawings]

[0012] [Figure 1]FIG. 2 is a schematic diagram showing one embodiment of a process for producing a printed wiring board using the photosensitive multilayer resin film of the present embodiment as a material for an interlayer insulating layer. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] In the numerical ranges described in this specification, the lower and upper limits of the numerical ranges may be replaced with values ​​shown in the examples. In addition, the lower and upper limits of the numerical ranges may be arbitrarily combined with the lower or upper limits of other numerical ranges. In the expression of a numerical range "AA to BB", the numerical values ​​AA and BB at both ends are included in the numerical range as the lower and upper limits, respectively.

[0014] In this specification, for example, the expression "10 or more" means 10 or a numerical value exceeding 10, and the same applies when the numerical values ​​are different. In addition, for example, the expression "10 or less" means 10 or a numerical value less than 10, and the same applies when the numerical values ​​are different.

[0015] In this specification, when there are multiple substances corresponding to each component, the content of each component means the total content of the multiple substances, unless otherwise specified.

[0016] In this specification, the term "solid content" refers to components other than the solvent, and components that are liquid at 25°C are also considered to be solid content.

[0017] In the present specification, the term "number of ring carbon atoms" refers to the number of carbon atoms necessary to form a ring, and does not include the number of carbon atoms of the substituents of the ring. For example, both the cyclohexane skeleton and the methylcyclohexane skeleton have 6 ring carbon atoms.

[0018] The expression "(meth)acrylic XX" means either or both of acrylic XX and the corresponding methacrylic XX. In addition, the expression "(meth)acryloyl group" means either or both of an acryloyl group and a methacryloyl group.

[0019] In this specification, when the term "layer" is used, for example, as an interlayer insulating layer, the term "layer" includes not only a solid layer, but also layers that are not solid but have island-like portions, have holes, and have an unclear interface with an adjacent layer.

[0020] The mechanism of action described in this specification is speculation and does not limit the mechanism by which the effects of the present embodiment are achieved.

[0021] Any combination of the descriptions in this specification is also included in this embodiment.

[0022] [Photosensitive multi-layer resin film] The photosensitive multilayer resin film of the present embodiment has A photosensitive multilayer resin film having a first resin composition layer and a second resin composition layer, The first resin composition layer and the second resin composition layer each include (A) a compound having an ethylenically unsaturated group, (B) a thermosetting resin, and (C) a photopolymerization initiator, The second resin composition layer further contains (D) an imidazole compound, The content of the imidazole compound (D) in the first resin composition layer is 0 to 0.4% by mass, The photosensitive multilayer resin film has a mass-based content of the imidazole compound (D) in the first resin composition layer that is less than a mass-based content of the imidazole compound (D) in the second resin composition layer.

[0023] In this specification, the individual components may be appropriately abbreviated as "component (A)", "component (B)", etc.

[0024] The first resin composition layer and the second resin composition layer of the photosensitive multilayer resin film of this embodiment can form a pattern such as a via by exposure and development. Therefore, the photosensitive multilayer resin film of this embodiment is suitable for use in forming an interlayer insulating layer having a photovia. In this specification, the term "photovia" refers to a via formed by a photolithography method, i.e., exposure and development.

[0025] The reason why the photosensitive multilayer resin film of the present embodiment has excellent storage stability and conductor adhesion is not clear, but is presumed to be as follows. The first and second resin composition layers of the photosensitive multilayer resin film of this embodiment each contain (A) a compound having an ethylenically unsaturated group, (B) a thermosetting resin, and (C) a photopolymerization initiator, and the second resin composition layer further contains (D) an imidazole compound. The (D) imidazole compound promotes the curing of the (B) thermosetting resin in the second resin composition layer and enhances the heat resistance of the interlayer insulating layer formed. In the photosensitive multilayer resin film of this embodiment, the content of the (D) imidazole compound in the first resin composition layer is 0 to 0.4 mass%, and the content of the (D) imidazole compound in the first resin composition layer is smaller than the content of the (D) imidazole compound in the second resin composition layer. In this way, by adjusting the content of the (D) imidazole compound in the first resin composition layer to be lower than that in the second resin composition layer, it is considered that the progress of unintended reactions is suppressed and the storage stability of the photosensitive multilayer resin film is improved. Furthermore, it is presumed that the curing reaction of the (B) thermosetting resin accelerated by the (D) imidazole compound in the second resin composition layer also accelerates the progress of the curing of the (B) thermosetting resin in the first resin composition layer under a heated environment, thereby resulting in sufficient curing of the (B) thermosetting resin in the first resin composition layer, and thereby exhibiting good conductor adhesion.

[0026] From the viewpoint of obtaining excellent heat resistance, storage stability, and conductor adhesion, it is preferable that the photosensitive multilayer resin film of this embodiment has a layer obtained by curing the first resin composition layer as a layer on which a circuit pattern is formed by copper plating, and a second resin composition layer as a layer having a surface to be attached when laminating the photosensitive multilayer resin film.

[0027] The thickness of the first resin composition layer is preferably 0.1 to 50 μm, more preferably 0.5 to 30 μm, and even more preferably 1 to 10 μm, from the viewpoints of heat resistance, storage stability, and conductor adhesion. The thickness of the second resin composition layer is preferably from 1 to 100 μm, more preferably from 3 to 50 μm, and even more preferably from 5 to 40 μm, from the viewpoints of heat resistance, storage stability, and adhesion to the conductor. The total thickness of the photosensitive multilayer resin film of the present embodiment is not particularly limited, and may be, for example, 2 to 110 μm, 4 to 60 μm, or 7 to 50 μm.

[0028] Hereinafter, each component contained in the first resin composition layer and the second resin composition layer will be described. In addition, among the following descriptions of the components (A) to (I), the descriptions of preferred embodiments of the components that may be contained in both the first resin composition layer and the second resin composition layer are common to the first resin composition layer and the second resin composition layer unless otherwise specified. In addition, among the following components (A) to (I), the components contained in both the first resin composition layer and the second resin composition layer may be the same as or different from each other. That is, for example, the component (A) contained in the first resin composition layer and the component (A) contained in the second resin composition layer may be the same as or different from each other. The same applies to the components (B) to (I).

[0029] <(A) Compound Having an Ethylenically Unsaturated Group> There are no particular limitations on the component (A) as long as it is a compound having an ethylenically unsaturated group. The component (A) may be used alone or in combination of two or more types.

[0030] The component (A) is a compound that exhibits photopolymerizability, particularly radical polymerizability, due to the presence of an ethylenically unsaturated group. In this specification, the term "ethylenically unsaturated group" refers to a substituent containing an ethylenically unsaturated bond. The term "ethylenically unsaturated bond" refers to a carbon-carbon double bond capable of undergoing an addition reaction, and does not include a double bond in an aromatic ring. Examples of the ethylenically unsaturated group include a vinyl group, an allyl group, a (meth)acryloyl group, a propargyl group, a butenyl group, an ethynyl group, a phenylethynyl group, a maleimide group, a nadimide group, etc. Among these, a (meth)acryloyl group is preferred from the viewpoint of reactivity.

[0031] From the viewpoint of enabling alkaline development, the first resin composition layer and the second resin composition layer each preferably contain, as the compound (A) having an ethylenically unsaturated group, a compound (A1) having an ethylenically unsaturated group and an acidic substituent, and from the viewpoint of forming an interlayer insulating layer having superior heat resistance and dielectric properties, it is preferable to contain, together with the component (A1), a monomer (A2) having two or more ethylenically unsaturated groups. The components (A1) and (A2) will be described below.

[0032] <(A1) Compound Having an Ethylenically Unsaturated Group and an Acidic Substituent> Examples of the acidic substituent contained in the component (A1) include a carboxy group, a sulfonic acid group, a phenolic hydroxyl group, etc. Of these, the carboxy group is preferred from the viewpoint of resolution. The acid value of the component (A1) is preferably from 20 to 200 mgKOH / g, more preferably from 40 to 180 mgKOH / g, and even more preferably from 70 to 150 mgKOH / g. When the acid value of the component (A1) is at least as high as the lower limit above, the alkaline developability tends to be better, whereas when the acid value of the component (A1) is at most the upper limit above, the dielectric constant tends to be better. The acid value of the component (A1) can be measured by the method described in the examples.

[0033] The weight average molecular weight (Mw) of the component (A1) is preferably 600 to 30,000, more preferably 800 to 20,000, still more preferably 1,000 to 10,000, and particularly preferably 1,200 to 4,000. When the weight average molecular weight (Mw) of the component (A1) is within the above range, it tends to be possible to form an interlayer insulating layer that is more excellent in conductor adhesion, heat resistance, and insulation reliability. In this specification, the weight average molecular weight (Mw) is a value determined by gel permeation chromatography (GPC) using tetrahydrofuran as a solvent and converted into standard polystyrene, and more specifically, is a value measured according to the method described in the Examples.

[0034] From the viewpoint of achieving a low dielectric constant and a low dielectric loss tangent, the component (A1) preferably contains an alicyclic skeleton. As the alicyclic skeleton of the component (A1), from the viewpoints of resolution and dielectric properties, an alicyclic skeleton having 5 to 20 ring carbon atoms is preferable, an alicyclic skeleton having 5 to 18 ring carbon atoms is more preferable, an alicyclic skeleton having 6 to 16 ring carbon atoms is even more preferable, an alicyclic skeleton having 7 to 14 ring carbon atoms is particularly preferable, and an alicyclic skeleton having 8 to 12 ring carbon atoms is most preferable.

[0035] From the viewpoints of resolution and dielectric properties, the alicyclic skeleton of the component (A1) preferably consists of two or more rings, more preferably two to four rings, and even more preferably three rings. Examples of alicyclic skeletons consisting of two or more rings include a norbornane skeleton, a decalin skeleton, a bicycloundecane skeleton, and a saturated dicyclopentadiene skeleton. Among these, from the viewpoints of resolution and dielectric properties, a saturated dicyclopentadiene skeleton is preferred. From a similar viewpoint, the component (A1) preferably contains an alicyclic skeleton represented by the following general formula (A1-1).

[0036] [ka] (In the formula, R A1 represents an alkyl group having 1 to 12 carbon atoms, and may be substituted anywhere in the alicyclic skeleton. 1 is an integer from 0 to 6. * indicates a binding site.)

[0037] In the above general formula (A1-1), R A1 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, etc. 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.

[0038] In the above general formula (A1-1), m 1 is an integer of 0 to 6, preferably an integer of 0 to 2, and more preferably 0. 1 When is an integer between 2 and 6, multiple R A1 may be the same or different. A1 may be substituted on the same carbon atom or on different carbon atoms, to the extent possible.

[0039] In the above general formula (A1-1), * represents a bonding site to another structure. The single bond having the bonding site * may be bonded to any carbon atom on the alicyclic skeleton, but is preferably bonded to the carbon atom represented by either 1 or 2 and the carbon atom represented by either 3 or 4 in the following general formula (A1-1'):

[0040] [ka] (In the formula, R A1 , m 1 and * are the same as those in the above general formula (A1-1).

[0041] The component (A1) is preferably a compound obtained by reacting a compound obtained by reacting an epoxy resin (a1) with an organic acid containing a (meth)acryloyl group (a2) with a polybasic acid anhydride containing a saturated group or an unsaturated group (a3). In the following description, the compound obtained by reacting (a1) the epoxy resin with (a2) the (meth)acryloyl group-containing organic acid may be referred to as "component (A')". Furthermore, the compound obtained by reacting the component (A') with the (a3) ​​saturated or unsaturated group-containing polybasic acid anhydride is sometimes referred to as an "acid-modified (meth)acryloyl group-containing epoxy resin derivative." Preferred embodiments of the component (A1) are described below.

[0042] ((a1) Epoxy resin) The (a1) epoxy resin preferably has two or more epoxy groups. The (a1) epoxy resin may be used alone or in combination of two or more kinds.

[0043] (a1) Epoxy resins are classified into, for example, 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.

[0044] (a1) Epoxy resins can be classified into various epoxy resins depending on the difference in the main skeleton, for example, epoxy resins having an alicyclic skeleton, novolac type epoxy resins, bisphenol type epoxy resins, aralkyl type epoxy resins, other epoxy resins, etc. Among these, epoxy resins having an alicyclic skeleton and novolac type epoxy resins are preferred.

[0045] [Epoxy resin having an alicyclic skeleton] The alicyclic skeleton of the epoxy resin having an alicyclic skeleton is explained in the same manner as the alicyclic skeleton of the component (A1) described above, and preferred embodiments are also the same. As the epoxy resin having an alicyclic skeleton, an epoxy resin represented by the following general formula (A1-2) is preferable.

[0046] [ka] (In the formula, R A1 R each independently represents an alkyl group having 1 to 12 carbon atoms, and may be substituted anywhere in the alicyclic skeleton. A2 Each independently represents an alkyl group having 1 to 12 carbon atoms. 1 is an integer between 0 and 6, m 2 is an integer between 0 and 3. n is a number between 0 and 50.)

[0047] In the above general formula (A1-2), R A1 is R in the above general formula (A1-1). A1 The preferred embodiments are also the same. R in the above general formula (A1-2) A2 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, etc. 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. In the above general formula (A1-2), m 1 is m in the above general formula (A1-1). 1 The preferred embodiments are also the same. In the above general formula (A1-2), m 2 represents an integer of 0 to 3, preferably 0 or 1, and more preferably 0. In the above general formula (A1-2), n represents the number of structural units in the parentheses and is a number from 0 to 50. Usually, an epoxy resin is a mixture of resins having different numbers of structural units in the parentheses, and in that case, n represents the average value of the mixture. n is preferably a number from 0 to 30.

[0048] As the epoxy resin having an alicyclic skeleton, a commercially available product may be used, and examples of the commercially available product include "XD-1000" (trade name, manufactured by Nippon Kayaku Co., Ltd.) and "EPICLON (registered trademark) HP-7200" (trade name, manufactured by DIC Corporation).

[0049] [Novolac-type epoxy resin] Examples of novolac type epoxy resins include bisphenol novolac type epoxy resins such as bisphenol A novolac type epoxy resins, bisphenol F novolac type epoxy resins, and bisphenol S novolac type epoxy resins; phenol novolac type epoxy resins, cresol novolac type epoxy resins, biphenyl novolac type epoxy resins, and naphthol novolac type epoxy resins. The novolac type epoxy resin is preferably an epoxy resin having a structural unit represented by the following general formula (A1-3).

[0050] [ka] (In the formula, R A3 each independently represents a hydrogen atom or a methyl group; Y A1 Each of Y independently represents a hydrogen atom or a glycidyl group. A1 At least one of the groups is a glycidyl group.

[0051] R in the above general formula (A1-3) A3 From the viewpoint of resolution, it is preferable that Y in the above general formula (A1-3) is a hydrogen atom. A1 is preferably a glycidyl group.

[0052] The number of structural units in the epoxy resin (a1) having the structural unit represented by the above general formula (A1-3) is a number equal to or greater than 1, and is preferably a number from 10 to 100, more preferably a number from 13 to 80, and even more preferably a number from 15 to 70. When the number of the structural units is within the above range, an interlayer insulating layer having better conductor adhesion, heat resistance, and insulation reliability tends to be formed.

[0053] [Bisphenol-type epoxy resin] Examples of bisphenol type epoxy resins include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, and 3,3',5,5'-tetramethyl-4,4'-diglycidyloxydiphenylmethane.

[0054] [Aralkyl-type epoxy resin] Examples of the aralkyl type epoxy resin include phenol aralkyl type epoxy resin, biphenyl aralkyl type epoxy resin, and naphthol aralkyl type epoxy resin.

[0055] [Other epoxy resins] Examples of other epoxy resins include stilbene type epoxy resins, naphthalene type epoxy resins, naphthylene ether type epoxy resins, biphenyl type epoxy resins, dihydroanthracene type epoxy resins, cyclohexanedimethanol type epoxy resins, trimethylol type epoxy resins, alicyclic epoxy resins, aliphatic linear epoxy resins, heterocyclic epoxy resins, spiro ring-containing epoxy resins, and rubber-modified epoxy resins.

[0056] ((a2) (Meth)acryloyl group-containing organic acid) (a2) The (meth)acryloyl group-containing organic acid is preferably a (meth)acryloyl group-containing monocarboxylic acid. Examples of (meth)acryloyl group-containing monocarboxylic acids include acrylic acid, acrylic acid dimers, methacrylic acid, acrylic acid derivatives such as β-furfurylacrylic acid, β-styrylacrylic acid, cinnamic acid, crotonic acid, and α-cyanocinnamic acid; half-ester compounds which are reaction products of hydroxyl group-containing acrylates and dibasic acid anhydrides; and half-ester compounds which are reaction products of (meth)acryloyl group-containing monoglycidyl ethers or (meth)acryloyl group-containing monoglycidyl esters and dibasic acid anhydrides. The component (a2) may be used alone or in combination of two or more types.

[0057] In the reaction between the (a1) component and the (a2) component, the amount of the (a2) component used is preferably 0.6 to 1.1 equivalents, more preferably 0.8 to 1.05 equivalents, and even more preferably 0.9 to 1.02 equivalents per equivalent of the epoxy group of the (a1) component. By reacting the (a1) component and the (a2) component in the above ratio, the polymerizability of the (A1) component is improved, and the resolution tends to be improved.

[0058] The (a1) and (a2) components are preferably dissolved in an organic solvent and reacted with each other while heating. In addition, when reacting, a known reaction catalyst, polymerization inhibitor, etc. may be used as necessary.

[0059] When a (meth)acryloyl group-containing monocarboxylic acid is used as the (a2) component, the (A') component obtained by reacting the (a1) component with the (a2) component has a hydroxyl group formed by a ring-opening addition reaction between the epoxy group of the (a1) component and the carboxyl group of the (a2) component. Next, the (A') component is reacted with the (a3) ​​saturated or unsaturated group-containing polybasic acid anhydride to obtain an acid-modified (meth)acryloyl group-containing epoxy resin derivative in which the hydroxyl group of the (A') component and the acid anhydride group of the (a3) ​​component are half-esterified. The hydroxyl group of the (A') component may also include the hydroxyl group originally present in the (a1) component.

[0060] ((a3) Polybasic acid anhydride) The (a3) ​​component may contain a saturated group or an unsaturated group. Examples of the (a3) ​​component include succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride, and itaconic anhydride. Among these, tetrahydrophthalic anhydride is preferred from the viewpoint of resolution. The (a3) ​​component may be used alone or in combination of two or more.

[0061] In the reaction between the component (A') and the component (a3), for example, the acid value of the acid-modified (meth)acryloyl group-containing epoxy resin derivative can be well adjusted by reacting 0.1 to 1.0 equivalent of the component (a3) ​​with 1 equivalent of the hydroxyl group in the component (A').

[0062] <(A2) Monomer Having Two or More Ethylenically Unsaturated Groups> The component (A2) is used primarily as a crosslinking agent for the component (A1). By containing the component (A2) together with the component (A1), the first resin composition layer and the second resin composition layer tend to have an increased crosslinking density due to a photoradical polymerization reaction, thereby improving the resistance to an alkaline developer and the resolution, and also forming an interlayer insulating layer with superior heat resistance. The component (A2) may or may not have an acidic substituent.

[0063] The number of ethylenically unsaturated groups contained in the component (A2) is 2 or more, and from the viewpoint of resolution and of forming an interlayer insulating layer having superior heat resistance and dielectric properties, the number is preferably 2 to 10, more preferably 2 to 8, and even more preferably 2 to 7.

[0064] Examples of the component (A2) include a bifunctional monomer having two ethylenically unsaturated groups, and a polyfunctional monomer having three or more ethylenically unsaturated groups.

[0065] Examples of bifunctional monomers having two ethylenically unsaturated groups include aliphatic di(meth)acrylates such as trimethylolpropane di(meth)acrylate, polypropylene glycol di(meth)acrylate, and polyethylene glycol di(meth)acrylate; di(meth)acrylates having an alicyclic skeleton such as dicyclopentadiene di(meth)acrylate and tricyclodecane dimethanol di(meth)acrylate; and aromatic di(meth)acrylates such as 2,2-bis(4-(meth)acryloxypolyethoxypolypropoxyphenyl)propane and bisphenol A diglycidyl ether di(meth)acrylate.

[0066] Examples of polyfunctional monomers having three or more 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; and (meth)acrylate compounds having a skeleton derived from diglycerin. Here, the "(meth)acrylate compound having a skeleton derived from XXX" (wherein XXX is the name of the compound) means an esterification product of XXX and (meth)acrylic acid, and the esterification product also includes a compound modified with an alkyleneoxy group.

[0067] Among the above options, from the viewpoints of resolution and of forming an interlayer insulating layer having superior conductor adhesion, the component (A2) is preferably a polyfunctional monomer having three or more ethylenically unsaturated groups, and more preferably a (meth)acrylate compound having a skeleton derived from trimethylolpropane or a (meth)acrylate compound having a skeleton derived from dipentaerythritol.

[0068] The component (A) may or may not contain a compound other than the components (A1) and (A2). Examples of the component other than the components (A1) and (A2) include a monofunctional monomer having one ethylenically unsaturated group and no acidic substituent.

[0069] (Content of Component (A) in First Resin Composition Layer) The content of component (A) in the first resin composition layer is preferably 10 to 80 mass %, more preferably 20 to 60 mass %, and even more preferably 30 to 50 mass %, based on the total amount of resin components in the first resin composition layer, from the viewpoints of the resolution of the photosensitive multilayer resin film and the dielectric properties of the interlayer insulating layer formed. In this specification, the term "resin component" refers to a resin and a compound that forms a resin by a curing reaction. For example, in the photosensitive multilayer resin film of the present embodiment, the components (A), (B), (F) and (I) are classified as resin components. On the other hand, components (C), (D), (E), (G) and (H) are not included in the resin component.

[0070] When the first resin composition layer contains the (A1) component, the content of the (A1) component in the first resin composition layer is, from the viewpoints of resolution and the dielectric properties of the interlayer insulating layer to be formed, preferably 5 to 70 mass %, more preferably 10 to 50 mass %, and even more preferably 20 to 40 mass %, based on the total amount of resin components in the first resin composition layer.

[0071] When the first resin composition layer contains the (A1) component and the (A2) component, the content of the (A2) component in the first resin composition layer is, from the viewpoints of resolution and the dielectric properties of the interlayer insulating layer to be formed, preferably 5 to 80 parts by mass, more preferably 10 to 60 parts by mass, and even more preferably 20 to 40 parts by mass per 100 parts by mass of the (A1) component in the first resin composition layer.

[0072] (Content of Component (A) in Second Resin Composition Layer) The content of component (A) in the second resin composition layer is preferably 20 to 90 mass%, more preferably 40 to 80 mass%, and even more preferably 50 to 70 mass%, based on the total amount of resin components in the second resin composition layer, from the viewpoints of resolution and the dielectric properties of the interlayer insulating layer formed.

[0073] When the second resin composition layer contains the (A1) component, the content of the (A1) component in the second resin composition layer is, from the viewpoints of resolution and the dielectric properties of the interlayer insulating layer to be formed, preferably 5 to 70 mass %, more preferably 10 to 50 mass %, and even more preferably 20 to 40 mass %, based on the total amount of resin components in the second resin composition layer.

[0074] When the second resin composition layer contains the (A1) component and the (A2) component, the content of the (A2) component in the second resin composition layer is, from the viewpoints of resolution and the dielectric properties of the interlayer insulating layer to be formed, preferably 20 to 100 parts by mass, more preferably 40 to 90 parts by mass, and even more preferably 60 to 80 parts by mass per 100 parts by mass of the (A1) component in the second resin composition layer.

[0075] <(B) Thermosetting resin> The (B) thermosetting resin is not particularly limited as long as it is a resin having thermosetting properties. When the first resin composition layer and the second resin composition layer contain the thermosetting resin (B), the heat resistance of the interlayer insulating layer formed tends to be improved. The (B) thermosetting resin may be used alone or in combination of two or more kinds.

[0076] Examples of the (B) thermosetting resin include epoxy resins, isocyanate resins, maleimide resins, phenolic resins, cyanate resins, benzoxazine resins, oxetane resins, amino resins, unsaturated polyester resins, allyl resins, vinyl resins, dicyclopentadiene resins, silicone resins, triazine resins, melamine resins, and other known thermosetting resins.

[0077] Among the above options, from the viewpoint of forming an interlayer insulating layer having superior heat resistance and conductor adhesion, it is preferable that the first resin composition layer and the second resin composition layer each contain, as component (B), one or more resins selected from the group consisting of epoxy resins, maleimide resins, allyl resins, and vinyl resins, and it is more preferable that they contain an epoxy resin.

[0078] (Epoxy resin) The epoxy resin is preferably an epoxy resin having two or more epoxy groups. Epoxy resins are classified into, for example, 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.

[0079] Epoxy resins are also classified into various types of epoxy resins according to the difference in the main skeleton, and each of the above types of epoxy resins is further classified as follows: Specifically, epoxy resins include, for example, bisphenol-based epoxy resins such as bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, and bisphenol S-type epoxy resins; bisphenol-based novolac-type epoxy resins such as bisphenol A-type epoxy resins and bisphenol F-type novolac-type epoxy resins; novolac-type epoxy resins other than the above bisphenol-based novolac-type epoxy resins, such as phenol novolac-type epoxy resins, cresol novolac-type epoxy resins, and biphenyl novolac-type epoxy resins; phenol aralkyl-type epoxy resins; stilbene-type epoxy resins; epoxy resins; naphthalene skeleton-containing epoxy resins such as naphthol novolac type epoxy resins, naphthol type epoxy resins, naphthol aralkyl type epoxy resins, and naphthylene ether type epoxy resins; biphenyl type epoxy resins; biphenyl aralkyl type epoxy resins; xylylene type epoxy resins; dihydroanthracene type epoxy resins; alicyclic epoxy resins such as saturated dicyclopentadiene type epoxy resins; heterocyclic epoxy resins; spiro ring-containing epoxy resins; cyclohexane dimethanol type epoxy resins; trimethylol type epoxy resins; aliphatic linear epoxy resins; and rubber-modified epoxy resins.

[0080] Among these, the epoxy resin is preferably a bisphenol-based epoxy resin, a naphthalene skeleton-containing epoxy resin, or a biphenylaralkyl-type epoxy resin, and more preferably a naphthalene skeleton-containing epoxy resin or a biphenylaralkyl-type epoxy resin.

[0081] (Isocyanate resin) Examples of the isocyanate resin include aliphatic isocyanates such as trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, and trimethylhexamethylene diisocyanate; alicyclic isocyanates such as 1,3-cyclopentane diisocyanate, 1,4-cyclohexane diisocyanate, 1,2-cyclohexane diisocyanate, isophorone diisocyanate, and norbornane diisocyanate; aromatic isocyanates such as xylylene diisocyanate, 2,4-tolylene diisocyanate, and 2,6-tolylene diisocyanate; biuret forms thereof; and nurate forms thereof. Among these, aliphatic isocyanates are preferred, and hexamethylene diisocyanate is more preferred.

[0082] (Maleimide resin) Examples of the maleimide resin include aromatic maleimide compounds having an N-substituted maleimide group directly bonded to an aromatic ring, aliphatic maleimide compounds having an N-substituted maleimide group directly bonded to an aliphatic hydrocarbon group, etc. Among these, from the viewpoints of heat resistance and handling, aromatic maleimide compounds are preferred, and aromatic bismaleimide compounds are more preferred. Examples of aromatic maleimide compounds include bis(4-maleimidophenyl)methane, 2,2-bis[4-(4-maleimidophenoxy)phenyl]propane, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide, polyphenylmethane maleimide, biphenylaralkyl-type maleimide resins, and aromatic bismaleimide resins having an indane skeleton.

[0083] (Content of Component (B) in First Resin Composition Layer) From the viewpoint of forming an interlayer insulating layer having superior conductor adhesion and heat resistance, the content of the (B) thermosetting resin in the first resin composition layer is preferably 20 to 80 mass %, more preferably 30 to 70 mass %, and even more preferably 40 to 60 mass %, based on the total amount of resin components in the first resin composition layer.

[0084] When the first resin composition layer contains an epoxy resin as the (B) thermosetting resin, the content of the epoxy resin in the first resin composition layer is, from the viewpoint of forming an interlayer insulating layer having superior conductor adhesion and heat resistance, preferably 10 to 80 mass%, more preferably 20 to 70 mass%, and even more preferably 30 to 60 mass%, based on the total amount of resin components in the first resin composition layer. From the viewpoint of forming an interlayer insulating layer having superior conductor adhesion, it is preferable that the first resin composition layer and the second resin composition layer each contain an epoxy resin as the (B) thermosetting resin, and that the content of the epoxy resin on a mass basis in the first resin composition layer is greater than the content of the epoxy resin on a mass basis in the second resin composition layer.

[0085] When the first resin composition layer contains an isocyanate resin as the (B) thermosetting resin, the content of the isocyanate resin in the first resin composition layer is, from the viewpoint of forming an interlayer insulating layer having superior conductor adhesion and heat resistance, preferably 1 to 30 mass%, more preferably 3 to 20 mass%, and even more preferably 5 to 15 mass%, based on the total amount of resin components in the first resin composition layer.

[0086] (Content of Component (B) in Second Resin Composition Layer) From the viewpoint of forming an interlayer insulating layer having superior heat resistance and dielectric properties, the content of the (B) thermosetting resin in the second resin composition layer is preferably 10 to 70 mass %, more preferably 20 to 60 mass %, and even more preferably 30 to 50 mass %, based on the total amount of the resin components in the second resin composition layer.

[0087] When the second resin composition layer contains an epoxy resin as the (B) thermosetting resin, the content of the epoxy resin in the second resin composition layer is preferably 5 to 60 mass%, more preferably 10 to 50 mass%, and even more preferably 15 to 40 mass%, based on the total amount of resin components in the second resin composition layer, from the viewpoint of forming an interlayer insulating layer having superior heat resistance and dielectric properties.

[0088] When the second resin composition layer contains an isocyanate resin as the (B) thermosetting resin, the content of the isocyanate resin in the second resin composition layer is preferably 2 to 50 mass%, more preferably 5 to 40 mass%, and even more preferably 10 to 30 mass%, based on the total amount of resin components in the second resin composition layer, from the viewpoint of forming an interlayer insulating layer having superior heat resistance and dielectric properties.

[0089] <(C) Photopolymerization initiator> The photopolymerization initiator (C) is a polymerization initiator for a photoradical polymerization reaction of the ethylenically unsaturated group contained in the component (A). By including the photopolymerization initiator (C) in the first resin composition layer and the second resin composition layer, the resolution tends to be further improved. The (C) photopolymerization initiator may be used alone or in combination of two or more kinds.

[0090] Examples of the (C) photopolymerization initiator include benzoin-based compounds such as benzoin, benzoin methyl ether, and benzoin isopropyl ether; acetophenone-based compounds 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-[4-(methylthio)benzoyl]-2-(4-morpholinyl)propane, and N,N-dimethylaminoacetophenone; anthraquinone-based compounds such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, and 2-aminoanthraquinone; ketal-based compounds such as acetophenone dimethyl ketal and benzyl dimethyl ketal; 9- Acridine compounds such as phenylacridine and 1,7-bis(9,9'-acridinyl)heptane; acylphosphine oxide compounds such as phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide; 1,2-octanedione-1-[4-(phenylthio)phenyl]-2-(O-benzoyloxime), 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone 1-(O-acetyloxime) oxime ester compounds such as 1-phenyl-1,2-propanedione-2-[O-(ethoxycarbonyl)oxime]; thioxanthone compounds such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-diisopropylthioxanthone; benzophenone compounds such as 4,4'-bis(dimethylamino)benzophenone, 4,4'-bis(diethylamino)benzophenone, etc. Among these, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide and 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone 1-(O-acetyloxime) are preferred.

[0091] (Content of Component (C) in First Resin Composition Layer) From the viewpoint of easily obtaining a suitable polymerization reaction promoting effect, the content of the (C) photopolymerization initiator in the first resin composition layer is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, and even more preferably 0.1 to 1 part by mass, relative to 100 parts by mass of the (A) component in the first resin composition layer.

[0092] (Content of Component (C) in Second Resin Composition Layer) From the viewpoint of easily obtaining a suitable polymerization reaction promoting effect, the content of the (C) photopolymerization initiator in the second resin composition layer is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, and even more preferably 0.1 to 1 part by mass, relative to 100 parts by mass of the (A) component in the second resin composition layer.

[0093] <(D) Imidazole Compound> The second resin composition layer further contains (D) an imidazole compound. By including the (D) imidazole compound in the second resin composition layer, the interlayer insulating layer formed from the photosensitive multilayer resin film of the present embodiment has excellent heat resistance and adhesion to a conductor.

[0094] (D) Examples of the imidazole compound include 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 2-phenylimidazole, 1-benzyl-2-phenylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, isocyanate masked imidazole (addition reaction product of hexamethylene diisocyanate resin and 2-ethyl-4-methylimidazole), etc. Among these, 1-benzyl-2-phenylimidazole is preferred from the viewpoint of storage stability and conductor adhesion of the photosensitive multilayer resin film. The (D) imidazole compound may be used alone or in combination of two or more kinds.

[0095] (Content of Component (D) in First Resin Composition Layer) In addition, the content of the (D) imidazole compound in the first resin composition layer is 0 to 0.4 mass%, preferably 0 to 0.3 mass%, more preferably 0 to 0.2 mass%, even more preferably 0 to 0.1 mass%, still more preferably 0 to 0.05 mass%, and particularly preferably 0 mass%, from the viewpoints of storage stability and conductor adhesion of the photosensitive multilayer resin film. In addition, the content of the (D) imidazole compound in the first resin composition layer is preferably 5 parts by mass or less, more preferably 1 part by mass or less, and even more preferably 0 part by mass, relative to 100 parts by mass of the (B) thermosetting resin in the first resin composition layer, from the viewpoints of the storage stability and conductor adhesion of the photosensitive multilayer resin film.

[0096] (Content of Component (D) in Second Resin Composition Layer) The content of the (D) imidazole compound in the second resin composition layer is preferably 0.1 to 5 mass %, more preferably 0.2 to 2 mass %, and even more preferably 0.3 to 1 mass %, from the viewpoints of storage stability and conductor adhesion of the photosensitive multilayer resin film. In addition, the content of the (D) imidazole compound in the second resin composition layer is preferably 0.2 to 10 parts by mass, more preferably 0.5 to 5 parts by mass, and even more preferably 1 to 3 parts by mass, relative to 100 parts by mass of the (B) thermosetting resin in the second resin composition layer, from the viewpoints of storage stability and conductor adhesion of the photosensitive multilayer resin film.

[0097] The difference between the mass-based content of the (D) imidazole compound in the first resin composition layer and the mass-based content of the (D) imidazole compound in the second resin composition layer [content of the second resin composition layer - content of the first resin composition layer] is preferably 0.1 to 5 mass%, more preferably 0.2 to 2 mass%, and even more preferably 0.3 to 1 mass%, from the viewpoints of the storage stability and conductor adhesion of the photosensitive multilayer resin film.

[0098] <(E) Inorganic filler> It is preferable that the first resin composition layer and the second resin composition layer further contain (E) an inorganic filler. When the first resin composition layer contains the inorganic filler (E), the layer obtained by curing the first resin composition layer tends to exhibit high adhesion to a conductor. Moreover, from the viewpoint of forming an interlayer insulating layer having low thermal expansion properties, heat resistance, and flame retardancy, the second resin composition layer also preferably contains an inorganic filler (E).

[0099] (E) Examples of inorganic fillers include silica, alumina, titanium oxide, mica, beryllia, barium titanate, potassium titanate, strontium titanate, calcium titanate, aluminum carbonate, magnesium hydroxide, aluminum hydroxide, aluminum silicate, calcium carbonate, calcium silicate, magnesium silicate, silicon nitride, boron nitride, clay, talc, aluminum borate, silicon carbide, etc. Among these, silica is preferred from the viewpoints of low thermal expansion and conductor adhesion. Examples of silica include precipitated silica produced by a wet method and having a high water content, and dry method silica produced by a dry method and containing almost no bound water, etc. Furthermore, examples of dry method silica include crushed silica, fumed silica, fused silica, etc., depending on the production method. The silica may be surface-treated with a coupling agent such as a silane coupling agent.

[0100] (E) Volume average particle size of inorganic filler (D 50 ) is preferably 0.01 to 3.0 μm, more preferably 0.1 to 2.5 μm, and even more preferably 0.3 to 2.0 μm, from the viewpoint of resolution. In this specification, the volume average particle diameter (D 50 ) can be calculated as the particle size equivalent to 50% (volume basis) of the cumulative value in the particle size distribution by measuring particles dispersed in a solvent with a refractive index of 1.38 using a submicron particle analyzer (manufactured by Beckman Coulter, Inc., product name: N5) in accordance with the international standard ISO 13321.

[0101] (Content of Inorganic Filler (E) in First Resin Composition Layer) The content of the (E) inorganic filler in the first resin composition layer is preferably 10 to 70 mass %, more preferably 20 to 60 mass %, and even more preferably 30 to 50 mass %, from the viewpoint of forming an interlayer insulating layer that is excellent in low thermal expansion, heat resistance, flame retardancy, and conductor adhesion.

[0102] (Content of Inorganic Filler (E) in Second Resin Composition Layer) The content of the (E) inorganic filler in the second resin composition layer is preferably 5 to 65 mass %, more preferably 15 to 55 mass %, and even more preferably 25 to 45 mass %, from the viewpoint of forming an interlayer insulating layer that is excellent in low thermal expansion, heat resistance, and flame retardancy.

[0103] <(F) Elastomer> Each of the first resin composition layer and the second resin composition layer may further contain an elastomer (F). By including the (F) elastomer in the first resin composition layer and the second resin composition layer, the interlayer insulating layer formed tends to have further improved adhesion to a conductor. The (F) elastomer may be used alone or in combination of two or more kinds.

[0104] Examples of the (F) elastomer include polybutadiene-based elastomers, polyester-based elastomers, styrene-based elastomers, olefin-based elastomers, urethane-based elastomers, polyamide-based elastomers, acrylic-based elastomers, silicone-based elastomers, derivatives of these elastomers, etc. Among these, polybutadiene-based elastomers are preferred from the viewpoint of compatibility with the resin component and from the viewpoint of forming an interlayer insulating layer having superior conductor adhesion.

[0105] Suitable examples of polybutadiene elastomers include those containing 1,2-vinyl groups derived from 1,3-butadiene. From the viewpoint of resolution, the polybutadiene elastomer is preferably a polybutadiene elastomer having an acid anhydride group, and more preferably a polybutadiene elastomer having an acid anhydride group derived from maleic anhydride. When the polybutadiene-based elastomer has an acid anhydride group, the number of acid anhydride groups in one molecule is preferably 1 to 12, more preferably 3 to 11, and even more preferably 6 to 10, from the viewpoints of resolution and of forming an interlayer insulating layer having a more excellent relative dielectric constant.

[0106] The number average molecular weight (Mn) of the (F) elastomer is preferably from 1,000 to 100,000, more preferably from 2,000 to 50,000, still more preferably from 3,000 to 10,000, and particularly preferably from 4,000 to 7,000. In this specification, the number average molecular weight (Mn) is a value determined by gel permeation chromatography (GPC) using tetrahydrofuran as a solvent and converted into standard polystyrene, and more specifically, is a value measured according to the method described in the Examples.

[0107] (Content of Component (F) in First Resin Composition Layer) From the viewpoint of forming an interlayer insulating layer having superior heat resistance and adhesion to a conductor, the content of the (F) elastomer in the first resin composition layer is preferably 1 to 30 mass %, more preferably 3 to 20 mass %, and even more preferably 5 to 15 mass %, based on the total amount of the resin components in the first resin composition layer.

[0108] (Content of Component (F) in Second Resin Composition Layer) From the viewpoint of forming an interlayer insulating layer having superior heat resistance and adhesion to a conductor, the content of the (F) elastomer in the second resin composition layer is preferably 0 to 20 mass%, more preferably 0 to 10 mass%, and even more preferably 0 to 5 mass%, based on the total amount of the resin components in the second resin composition layer.

[0109] <(G)Organic peroxide> Each of the first resin composition layer and the second resin composition layer preferably further contains an organic peroxide (G), which is a polymerization initiator for a thermal radical polymerization reaction of the ethylenically unsaturated groups contained mainly in the component (A) and, if necessary, in the component (B). When the first resin composition layer and the second resin composition layer contain an organic peroxide (G), the interlayer insulating layer formed tends to have further improved heat resistance, dielectric properties, and the like. The (G) organic peroxides may be used alone or in combination of two or more kinds.

[0110] (G) Examples of organic peroxides include peroxyketals such as 1,1-di(t-butylperoxy)cyclohexane, 2,2-di(t-butylperoxy)butane, 2,2-di(4,4-di-t-butylperoxycyclohexyl)propane, and 1,1-di(t-amylperoxy)cyclohexane; hydroperoxides such as cumene hydroperoxide and t-butyl hydroperoxide; alkyl peroxides such as t-butyl peroxyacetate and t-amyl peroxyisononanoate; t-butyl cumyl peroxide and di-t-butyl Examples of the peroxycarbonyl peroxide include dialkyl peroxides such as dibutyl peroxide, dicumyl peroxide, di-t-hexyl peroxide, and 1,3-di(t-butylperoxyisopropyl)benzene; peroxyesters such as t-butyl peroxyacetate, t-butyl peroxybenzoate, and t-butylperoxyisopropyl monocarbonate; peroxycarbonates such as t-butylperoxyisopropyl carbonate and polyether tetrakis(t-butylperoxycarbonate); and diacyl peroxides such as dibenzoyl peroxide. Among these, 1,3-di(t-butylperoxyisopropyl)benzene is preferred.

[0111] (Content of Component (G) in First Resin Composition Layer) When the first resin composition layer contains an organic peroxide (G), the content of the organic peroxide (G) in the first resin composition layer is, from the viewpoint of forming an interlayer insulating layer having superior heat resistance and conductor adhesion, preferably 0.1 to 10 parts by mass, more preferably 1 to 7 parts by mass, and even more preferably 1.5 to 4 parts by mass per 100 parts by mass of the component (A) in the first resin composition layer.

[0112] (Content of Component (G) in Second Resin Composition Layer) When the second resin composition layer contains an organic peroxide (G), the content of the organic peroxide (G) in the second resin composition layer is, from the viewpoint of forming an interlayer insulating layer having superior heat resistance and conductor adhesion, preferably 0.1 to 10 parts by mass, more preferably 1 to 7 parts by mass, and even more preferably 1.5 to 4 parts by mass per 100 parts by mass of the component (A) in the second resin composition layer.

[0113] <(H) Other Ingredients> The first resin composition layer and the second resin composition layer may contain components other than the above-mentioned components as (H) other components, if necessary. (H) Other components include, for example, resins other than the above-mentioned components; photosensitizers; polymerization inhibitors; foam stabilizers; pigments; adhesion aids such as melamine; foam stabilizers such as silicone compounds; thickeners; and flame retardants. These may be used alone or in combination of two or more. The content of the (H) other components in the first resin composition layer or the second resin composition layer may be adjusted appropriately depending on the respective purposes, and may be 0.01 to 10 mass %, 0.05 to 5 mass %, or 0.1 to 1 mass % in the resin composition layer containing the respective components.

[0114] <(I) Fluorine-containing resin> The photosensitive multilayer resin film of the present embodiment may or may not contain (I) a fluorine-containing resin. From the viewpoint of reducing residues at the bottom of the vias, however, it is preferable that the photosensitive multilayer resin film does not contain (I) a fluorine-containing resin.

[0115] (I) Examples of fluorine-containing resins include polymonofluoroethylene, polydifluoroethylene, polytrifluoroethylene, polytetrafluoroethylene, polyhexafluoropropylene, polyvinyl fluoride, and polyvinylidene fluoride.

[0116] (Content of Fluorine-Containing Resin (I) in First Resin Composition Layer) From the viewpoint of reducing residue at the bottom of the via, the content of the (I) fluorine-containing resin in the first resin composition layer is preferably 10 mass % or less, more preferably 5 mass % or less, even more preferably 1 mass % or less, and still more preferably 0 mass %, based on the total amount of the resin components in the first resin composition layer.

[0117] (Content of Fluorine-Containing Resin (I) in Second Resin Composition Layer) From the viewpoint of reducing residue at the bottom of the via, the content of the (I) fluorine-containing resin in the second resin composition layer is preferably 10 mass % or less, more preferably 5 mass % or less, even more preferably 1 mass % or less, and still more preferably 0 mass %, based on the total amount of the resin components in the second resin composition layer.

[0118] (Content of (I) Fluorine-containing resin in photosensitive multilayer resin film) From the viewpoint of reducing residues at the bottom of the vias, the content of the (I) fluorine-containing resin in the photosensitive multilayer resin film of this embodiment is preferably 10 mass % or less, more preferably 5 mass % or less, even more preferably 1 mass % or less, and still more preferably 0 mass %, based on the total amount of resin components in the photosensitive multilayer resin film.

[0119] <Method for producing photosensitive multilayer resin film> The photosensitive multilayer resin film of this embodiment can be produced using a resin composition for forming a first resin composition layer (hereinafter also referred to as "resin composition (1)") and a resin composition for forming a second resin composition layer (hereinafter also referred to as "resin composition (2)"). The first resin composition layer can be formed from a resin composition (1), and the suitable content of each component in the total solid content of the resin composition (1) is the same as the suitable content of each component in the first resin composition layer. The second resin composition layer can be formed from a resin composition (2), and the suitable content of each component in the total solid content of the resin composition (2) is the same as the suitable content of each component in the second resin composition layer. Resin composition (1) and resin composition (2) can be produced by mixing the components to be incorporated in each layer and a diluent to be used as necessary. For example, a roll mill, a bead mill, a planetary mixer, a planetary mixer, a planetary mixer, or a rotary mixer can be used to mix the components.

[0120] The photosensitive multilayer resin film of the present embodiment having carrier films on both sides can be produced by forming a first resin composition layer and a second resin composition layer on separate carrier films using resin composition (1) and resin composition (2) and laminating the two layers together. Alternatively, the film can be produced by forming one of the resin composition layers on a carrier film, and applying the other resin composition onto the one resin composition layer to form the other resin composition layer.

[0121] Examples of the method for applying the resin composition (1) and the resin composition (2) include methods using a coating device such as a comma coater, a bar coater, a kiss coater, a roll coater, a gravure coater, or a die coater. The drying temperature when drying the coating films of the resin composition (1) and the resin composition (2) is preferably 60 to 150° C., more preferably 70 to 120° C., and even more preferably 80 to 100° C. The drying time is preferably 1 to 60 minutes, more preferably 2 to 30 minutes, and even more preferably 5 to 20 minutes.

[0122] Examples of the material for the carrier film include polyesters such as polyethylene terephthalate and polybutylene terephthalate, and polyolefins such as polypropylene and polyethylene. The thickness of the carrier film is preferably 5 to 100 μm, more preferably 10 to 60 μm, and further preferably 15 to 45 μm.

[0123] [Printed wiring board and its manufacturing method] The printed wiring board of this embodiment is a printed wiring board having an interlayer insulating layer that is a cured product of the photosensitive multilayer resin film of this embodiment. The "interlayer insulating layer" of the printed wiring board of this embodiment includes the state after various processing or treatments, such as via and wiring formation and roughening treatment, have been performed.

[0124] The method for producing the printed wiring board of this embodiment is not particularly limited as long as it is a method that uses the photosensitive multilayer resin film of this embodiment, but the method for producing the printed wiring board, which includes the following (1) to (4), is preferred. (1): The photosensitive multilayer resin film of the present embodiment is laminated onto one or both sides of a circuit board with the second resin composition layer serving as an attachment surface (hereinafter also referred to as "lamination process (1)"). (2): Forming an interlayer insulating layer having vias by exposing and developing the photosensitive multilayer resin film laminated in (1) above (hereinafter also referred to as "via forming step (2)"). (3): Heat-curing the interlayer insulating layer having the vias (hereinafter, also referred to as "heat-curing step (3)"). (4): forming a circuit pattern on the layer obtained by curing the first resin composition layer of the interlayer insulating layer (hereinafter, also referred to as "circuit pattern forming step (4)"). Hereinafter, the method for manufacturing a printed wiring board according to this embodiment will be described with reference to FIG. In this specification, for convenience, a given operation may be referred to as "XX step", but the "XX step" is not limited to the embodiments specifically described in this specification.

[0125] (Lamination process (1)) In the lamination step (1), the photosensitive multilayer resin film of the present embodiment is laminated onto one or both sides of a circuit board, with the second resin composition layer serving as an attachment surface. FIG. 1( a ) illustrates a process of forming a photosensitive layer 103 on both sides of a substrate 101 having a circuit pattern 102 . Photosensitive layer 103 can be formed by laminating the photosensitive multilayer resin film of this embodiment onto both sides of substrate 101 so that the second resin composition layer becomes the attachment surface. The lamination may be performed, for example, by pressure bonding under heat and pressure using a vacuum laminator or the like. After lamination, in the case where a carrier film is attached to the photosensitive layer 103, the carrier film may be peeled off before or after exposure to light, which will be described later.

[0126] (Via formation process (2)) In the via formation step (2), the photosensitive layer formed in the lamination step (1) is exposed to light and developed to form an interlayer insulating layer having vias. FIG. 1( b ) illustrates a process of forming an interlayer insulating layer 104 having a via 105 by exposing and developing the photosensitive layer 103 . By exposing the photosensitive layer 103 to light, a photoradical polymerization reaction is initiated, and the photosensitive multi-layer resin film is cured.

[0127] The exposure method of the photosensitive layer 103 may be, for example, a mask exposure method in which active light is irradiated in an image-wise manner through a negative or positive mask pattern called artwork, or a method in which active light is irradiated in an image-wise manner by a direct writing exposure method such as an LDI (Laser Direct Imaging) exposure method or a DLP (Digital Light Processing) exposure method. Examples of light sources for actinic rays include known light sources that effectively radiate ultraviolet or visible light, such as carbon arc lamps, mercury vapor arc lamps, high-pressure mercury lamps, xenon lamps, gas lasers such as argon lasers, solid-state lasers such as YAG lasers, and semiconductor lasers. The exposure dose may be appropriately adjusted depending on the light source used, the thickness of the photosensitive layer, etc. For example, when a photosensitive layer having a thickness of 1 to 100 μm is exposed to ultraviolet irradiation from a high-pressure mercury lamp, the exposure dose is preferably 10 to 1,000 mJ / cm. 2 , more preferably 50 to 700 mJ / cm 2 , and more preferably 150 to 400 mJ / cm 2 It is.

[0128] Next, if a carrier film is present on the photosensitive layer 103, the carrier film is removed before development. In the development, the uncured portion of the photosensitive layer 103 is removed, and the photocured portion is formed as the interlayer insulating layer 104 on the substrate. The developing method may be wet development or dry development, but wet development is preferred. As a method of wet development, a spray method is preferred from the viewpoint of improving resolution. Examples of the developer include an alkaline aqueous solution, a water-based developer, and an organic solvent-based developer. Among these, an alkaline aqueous solution is preferred. After the exposure and development, post-exposure may be performed in order to increase the degree of hardening of the interlayer insulating layer. The exposure dose in the post-exposure is preferably 0.2 to 10 J / cm 2 , more preferably 0.5 to 5 J / cm 2 It is.

[0129] The shape of the via is not particularly limited, and examples of the cross-sectional shape include a rectangle, an inverted trapezoid, etc. Note that an inverted trapezoid has a shape in which the upper side is longer than the lower side, and examples of the shape in a plan view include a circle, a rectangle, etc. In the formation of vias by the photolithography method of this embodiment, a via having an inverted trapezoidal cross-sectional shape can be formed, which is preferable because the plating copper has a high adhesion to the via wall surface. In the formation of vias by the photolithography method of this embodiment, the diameter of the vias can be made smaller than that of vias made by laser processing. The diameter of the vias formed by the manufacturing method of this embodiment may be, for example, 30 to 80 μm, 40 to 70 μm, or 50 to 65 μm.

[0130] (Heat curing process (3)) In the heat curing step (3), the interlayer insulating layer having the vias is heat cured. That is, in the heat curing step (3), the curing reaction of the thermosetting component contained in the photosensitive multilayer resin film of the present embodiment is promoted by heating. The heating temperature is preferably 100 to 300° C., more preferably 120 to 200° C., and further preferably 150 to 180° C. The heating time is preferably 0.3 to 3 hours, more preferably 0.5 to 2 hours, and further preferably 0.75 to 1.5 hours.

[0131] (Circuit pattern formation process (4)) Since the interlayer insulating layer formed as described above has a layer formed by curing the first resin composition layer exposed, in the circuit pattern forming step (4), a circuit pattern is formed on the layer formed by curing the first resin composition layer of the interlayer insulating layer. From the viewpoint of forming fine wiring, the circuit pattern is preferably formed by a semi-additive process in which roughening treatment, formation of a seed layer, formation of a resist pattern, formation of a copper circuit layer, and removal of the resist pattern are carried out in this order.

[0132] The roughening treatment is a treatment for roughening the surface of the interlayer insulating layer to form an anchor of projections and recesses. If smears occur in the via formation step (2), the roughening treatment and removal of the smears may be performed simultaneously using a roughening liquid. Examples of the roughening liquid include an alkaline permanganate roughening liquid such as a sodium permanganate roughening liquid; a chromium / sulfuric acid roughening liquid, and a sodium fluoride / chromium / sulfuric acid roughening liquid.

[0133] FIG. 1(c) illustrates the step of forming a seed layer 106. The seed layer 106 is for forming a power supply layer for electrolytic copper plating. The seed layer 106 can be formed by performing an electroless copper plating process using a palladium catalyst or the like on the via bottom, via wall surface, and the entire surface of the interlayer insulating layer.

[0134] FIG. 1( d ) illustrates the step of forming a resist pattern 107 on the seed layer 106 . The resist pattern 107 can be formed, for example, by thermocompression bonding a dry film resist onto the seed layer 106 using a roll laminator or the like, and then exposing and developing the resist. A commercially available product can be used as the dry film resist.

[0135] The dry film resist may be exposed through a mask on which a desired wiring pattern is drawn. After exposure, the dry film resist is developed using an alkaline aqueous solution to remove the unexposed parts, forming a resist pattern 107. Thereafter, if necessary, a plasma treatment may be performed to remove development residues of the dry film resist.

[0136] FIG. 1(e) illustrates the step of forming a copper circuit layer 108. The copper circuit layer 108 is preferably formed by electrolytic copper plating. As the electrolytic copper plating solution used for the electrolytic copper plating, for example, a commercially available electrolytic copper plating solution such as an electrolytic copper plating solution containing copper sulfate can be used. After the electrolytic copper plating, the resist pattern 107 is removed using an alkaline aqueous solution or an amine-based stripper, and then flash etching for removing the seed layer 106 between the wirings, removal of the palladium catalyst, etc. are appropriately performed by known methods. Furthermore, if necessary, a post-baking treatment may be performed to sufficiently heat-cure unreacted thermosetting components.

[0137] FIG. 1(f) shows a multilayer printed wiring board 100A that has been multilayered by repeating the above steps and has a solder resist layer 109 on the outermost surface. The solder resist layer 109 can be formed using a known photosensitive multi-layer resin film for solder resist.

[0138] The method for manufacturing a printed wiring board in which vias are formed using the photosensitive multilayer resin film of this embodiment has been described above, but since the photosensitive multilayer resin film of this embodiment has excellent pattern resolution, it is also suitable for forming cavities for incorporating chips, passive elements, etc. The cavities can be suitably formed, for example, by selecting a drawing pattern that can form a desired cavity when forming a pattern by exposing the photosensitive multilayer resin film in the above description of the printed wiring board.

[0139] [Semiconductor package] The semiconductor package of this embodiment is a semiconductor package having the printed wiring board of this embodiment. The semiconductor package of this embodiment can be manufactured, for example, by mounting a semiconductor element such as a semiconductor chip or memory at a predetermined position on the printed wiring board of this embodiment and sealing the semiconductor element with a sealing resin or the like. EXAMPLES

[0140] The present embodiment will be described in more detail below with reference to examples, but the present embodiment is not limited to these examples.

[0141] [Acid value measurement method] The acid value was calculated from the amount of potassium hydroxide aqueous solution required to neutralize the object to be measured.

[0142] [Method of measuring weight average molecular weight (Mw) and number average molecular weight (Mn)] The weight average molecular weight (Mw) and number average molecular weight (Mn) were measured using the following GPC measuring device and measuring conditions, and were calculated using the calibration curve of standard polystyrene. The calibration curve was created using a 5-sample set ("PStQuick MP-H" and "PStQuick B", Tosoh Corporation) as standard polystyrene. (GPC measurement device) GPC equipment: High-speed GPC equipment "HCL-8320GPC", detector is differential refractometer or UV, manufactured by Tosoh Corporation Column: TSKgel SuperMultipore HZ-H (column length: 15 cm, column inner diameter: 4.6 mm), manufactured by Tosoh Corporation (Measurement conditions) Solvent: Tetrahydrofuran (THF) Measurement temperature: 40℃ Flow rate: 0.35ml / min Sample concentration: 10mg / THF5ml Injection volume: 20μl

[0143] [Production of photosensitive multi-layer resin film] Examples 1 and 2, Comparative Examples 1 to 5 The components were mixed according to the composition shown in Table 1 (the units of values ​​in the table are parts by mass, and in the case of a solution, the amounts are calculated as solid contents), and kneaded using a three-roll mill and a planetary mixer. Methyl ethyl ketone was then added so that the solid content concentration became 65% by mass, to obtain a resin composition (1) for forming a first resin composition layer and a resin composition (2) for forming a second resin composition layer, respectively. Next, the resin composition (1) was applied onto a carrier film (PET film, manufactured by Teijin Limited, product name "G2-16", thickness 16 μm) and dried at 100°C for 10 minutes using a hot air convection dryer to form a first resin composition layer with a carrier film (thickness of the first resin composition layer: 5 μm). In addition, resin composition (2) was applied onto a carrier film (a PET film manufactured by Teijin Limited, product name "G2-16", thickness 16 μm) different from the above, and dried at 100°C for 10 minutes using a hot air convection dryer to form a second resin composition layer with a carrier film (thickness of the second resin composition layer: 20 μm). By bonding the resin composition layers of the first resin composition layer with a carrier film and the second resin composition layer with a carrier film obtained above together, a photosensitive multilayer resin film with double-sided carrier films (photosensitive multilayer resin film thickness 25 μm) having a carrier film, a first resin composition layer, a second resin composition layer and a carrier film in that order was obtained.

[0144] The photosensitive multilayer resin film thus produced was subjected to the following evaluations, and the results are shown in Table 1.

[0145] [Measurement of dielectric tangent (Df)] Two sheets of the photosensitive multilayer resin film with double-sided carrier films produced in each Example were prepared by peeling off the carrier film on the second resin composition layer side, and the second resin composition layers were bonded together. Next, with both sides of the carrier film still attached, a flatbed exposure machine was used to expose the film to a light intensity of 400 mJ / cm 2 The substrate was then exposed to ultraviolet light (wavelength 365 nm). The carrier films on both sides were then peeled off and removed, and a UV conveyor-type exposure machine was used to expose the substrate to a light intensity of 2 J / cm. 2 The specimen was then irradiated with ultraviolet light (wavelength 365 nm). It was then heated at 170°C for 1 hour using a hot air circulating dryer, and cut into a piece measuring 7 cm x 10 cm to prepare a sample for measuring the dielectric loss tangent (Df). The measurement sample obtained above was dried at 105° C. for 10 minutes using a hot air circulation dryer, and then the dielectric loss tangent (Df) was measured in the 10 GHz band using a split post dielectric resonator method (SPDR method).

[0146] [Evaluation of residue at via bottom] (1) Preparation of laminate for evaluation The copper foil surface of a printed wiring board substrate (manufactured by Resonac Co., Ltd., product name "MCL-E-679") in which copper foil (thickness 12 μm) was laminated on a glass epoxy base material was pre-roughened with a pre-roughening treatment liquid (manufactured by MEC Co., Ltd., product name "CZ-8100"), and then washed with water and dried. Next, the carrier film on the second resin composition layer side of the photosensitive multilayer resin film with double-sided carrier film produced in each example was peeled off and removed, and the exposed second resin composition layer was laminated on the copper foil of the printed wiring board substrate that had been pre-roughened. Note that a press-type vacuum laminator (manufactured by Meiki Seisakusho Co., Ltd., product name "MVLP-500") was used for lamination, and the lamination conditions were a press hot plate temperature of 70°C, a vacuum drawing time of 20 seconds, a lamination press time of 30 seconds, an atmospheric pressure of 4 kPa or less, and a pressure of 0.4 MPa. After the lamination treatment, the product was allowed to stand at room temperature for at least 1 hour to obtain a laminate for evaluation in which a photosensitive multilayer resin film and a carrier film were laminated in this order on the copper foil surface of the substrate for printed wiring board. (2) Sensitivity measurement A 41-step tablet was placed on the carrier film of the evaluation laminate obtained above. Next, exposure was performed using a direct imaging exposure device (manufactured by Oak Manufacturing Co., Ltd., product name "DXP-3512") using an ultra-high pressure mercury lamp as a light source. The exposure pattern used was a dot pattern in which dots with diameters of φ30 to 100 μm were arranged in a lattice pattern. After exposure, the laminate was left to stand at room temperature for 30 minutes, and then the carrier film of the laminate obtained above for evaluation was removed. The unexposed portion of the photosensitive multilayer resin film was spray-developed for 60 seconds using a 1% by mass aqueous solution of sodium carbonate at 30° C. After development, the amount of exposure energy at which the gloss remaining step number of the 41-step tablet became 4.0 was determined as the sensitivity of the photosensitive multilayer resin film (unit: mJ / cm 2 The pattern exposed at this sensitivity was used and evaluated according to the following criteria. (3) Evaluation of residue at the bottom of vias The bottom of a via (diameter 60 μm) formed by exposure and spray development with the exposure energy amount that is the sensitivity of the photosensitive multilayer resin film determined in (2) above was observed using an optical microscope and evaluated according to the following criteria. (Evaluation Criteria) A: No residue was observed. B: Residue was observed.

[0147] [Evaluation of adhesive strength with plated copper] (1) Preparation of laminate for evaluation and measurement of sensitivity of photosensitive multilayer resin film In the above [Evaluation of via bottom residue] (1) and (2), except that the exposure machine used was changed to a parallel light exposure machine using an ultra-high pressure mercury lamp as the light source (manufactured by ORC Manufacturing Co., Ltd., product name "EXM-1201"), the same operations as those in the above [Evaluation of via resolution] (1) and (2) were carried out to prepare a laminate for evaluation, and the amount of exposure energy at which the gloss remaining step number was 8.0 was determined. This was used as the sensitivity (unit: mJ / cm) of the photosensitive multilayer resin film. 2 ) was decided. (2) Exposure process and development process The carrier film of the evaluation laminate was peeled off and the entire surface was exposed to light with the amount of exposure energy corresponding to the sensitivity calculated above to cure the photosensitive multilayer resin film. After exposure, the film was left at room temperature for 30 minutes, and then the unexposed portion of the photosensitive multilayer resin film was spray-developed for 60 seconds using a 1% by mass aqueous solution of sodium carbonate at 30°C. (3) Post-cure treatment Next, a UV conveyor device with high-pressure mercury lamp irradiation type (manufactured by Oak Manufacturing Co., Ltd.) was used to expose the sample to 2 J / cm2. 2 After that, the film was heated at 170°C for 1 hour using a hot air circulating dryer. (4) Roughening treatment The laminate for evaluation after heating was treated with a swelling liquid "Swelling Dip Securigant P" at 70°C for 5 minutes, and then roughened with a roughening liquid "Dosing Securigant P500J" at 70°C for 10 minutes. Next, a neutralization treatment was performed with a neutralizing liquid "Reduction Conditioner Securigant P500" at 50°C for 5 minutes. Then, a hydrofluoric acid treatment was performed at room temperature for 10 minutes using buffered hydrofluoric acid "LAL1800 SA high purity buffered hydrofluoric acid". The swelling liquid, roughening liquid and neutralizing liquid were all manufactured by Atotech Japan Co., Ltd., and the buffered hydrofluoric acid was manufactured by Stella Chemifa Co., Ltd. (5) Plating The evaluation laminate after the roughening treatment was subjected to electroless plating treatment at 30° C. for 15 minutes using an electroless plating solution "Prigant MSK-DK" (manufactured by Atotech Japan Co., Ltd.). Then, electroplating treatment was performed at 24° C. and 2 A / dm using an electroplating solution "Cupracid HL" (manufactured by Atotech Japan Co., Ltd.). 2 The photosensitive multilayer resin film was cured at room temperature for 1.5 hours to form a copper plated layer on the cured photosensitive multilayer resin film. The thickness of the copper plated layer was 25 μm. (6) Measurement of adhesive strength with plated copper The adhesive strength to plated copper was measured in accordance with JIS C6481:1996 by measuring the vertical peel strength at 23°C and evaluated according to the following criteria. (Evaluation Criteria) A: More than 0.4kN / m B: More than 0.1kN / m~0.4kN / m or less C: 0.1kN / m or less

[0148] [Storage stability of photosensitive multilayer resin film] A cover film (manufactured by Tamapoly Co., Ltd., product name "NF15") was laminated onto the surface of the first resin composition layer with a carrier film (first resin composition layer thickness 5 μm) prepared in each example using a hand roller, and the resulting product was stored in an environment of 23°C ± 5°C for 96 hours and 168 hours. After peeling off the cover film of the first resin composition layer with carrier film after the above storage, the exposed first resin composition layer was bonded to the second resin composition layer with carrier film prepared in each example to obtain a photosensitive multilayer resin film with double-sided carrier films (photosensitive multilayer resin film thickness 25 μm) having a carrier film, a first resin composition layer, a second resin composition layer and a carrier film in that order. After that, the sensitivity of the photosensitive multilayer resin film was measured in the same manner as in the "Evaluation of residue at the bottom of the via" (unit: mJ / cm 2 ) and spray development to form vias (diameter 60 μm). The bottoms of the formed vias were observed using an optical microscope and evaluated according to the following criteria. (Evaluation Criteria) A: No residue was observed in the photosensitive multilayer resin film in which the first resin composition layer was stored for 96 hours and in the photosensitive multilayer resin film in which the first resin composition layer was stored for 168 hours. B: No residue was observed in the photosensitive multilayer resin film in which the first resin composition layer was stored for 96 hours, whereas residue was observed in the photosensitive multilayer resin film in which the first resin composition layer was stored for 168 hours. C: Residues were observed in both the photosensitive multilayer resin film in which the first resin composition layer was stored for 96 hours and the photosensitive multilayer resin film in which the first resin composition layer was stored for 168 hours.

[0149] [Table 1]

[0150] Details of each component listed in Table 1 are as follows.

[0151] [Component (A)] Compound having a carboxyl group and an acryloyl group: Nippon Kayaku Co., Ltd., product name "ZXR-1807H", acid value: 110 mgKOH / g, weight average molecular weight (Mw): 2,000 ·Dipentaerythritol hexaacrylate ·Trimethylolpropane triacrylate

[0152] [(B) Component] Biphenyl aralkyl type epoxy resin: Nippon Kayaku Co., Ltd., product name "NC-3000-L", epoxy group equivalent: 272g / eq Naphthol-type epoxy resin: Nippon Steel & Sumitomo Metal Corporation, product name "ESN-475V", epoxy group equivalent: 325g / eq Hexamethylene diisocyanate

[0153] [(C) component] Photopolymerization initiator 1: Phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide Photopolymerization initiator 2: 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone 1-(O-acetyloxime)

[0154] [(D) component] Imidazole compound 1: 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine Imidazole compound 2: 1-benzyl-2-phenylimidazole Imidazole compound 3: 1-cyanoethyl-2-ethyl-4-methylimidazole

[0155] [(E) component] Silica: Admatechs Co., Ltd., product name "SC2050-MB", average particle size (D 50 ):0.5μm, true density 2,200kg / m 3

[0156] [Component (F)] Polybutadiene elastomer: butadiene-styrene random copolymer, manufactured by Cray Valley, product name "Ricon 100", number average molecular weight (Mn): 4,500 Acid anhydride modified polybutadiene: Cray Valley Corporation, product name "Ricon131MA17", number average molecular weight (Mn): 5,400, number of acid anhydride groups per molecule: 9

[0157] [(G) component] Organic peroxide: 1,3-di(t-butylperoxyisopropyl)benzene

[0158] [(H) component] Sensitizer: 4,4'-bis-(diethylamino)benzophenone Polymerization inhibitor: 4-tert-butylpyrocatechol

[0159] [Component (I)] Polytetrafluoroethylene particles: Mitsubishi Pencil Co., Ltd., product name "MPT-N8", average particle size (D 50 ): 0.2~0.3μm

[0160] It can be seen from Table 1 that the photosensitive multilayer resin films of Examples 1 and 2 of this embodiment have excellent storage stability, and the cured products formed from the photosensitive multilayer resin films have excellent adhesion to conductors. [Explanation of symbols]

[0161] 100A Multilayer Printed Wiring Board 101 Substrate 102 Circuit Pattern 103 Photosensitive layer 104 Interlayer insulation layer 105 Beer 106 Seed Layer 107 Resist Pattern 108 Copper circuit layers 109 Solder resist layer

Claims

1. A photosensitive multilayer resin film having a first resin composition layer and a second resin composition layer, The first resin composition layer and the second resin composition layer each include (A) a compound having an ethylenically unsaturated group, (B) a thermosetting resin, and (C) a photopolymerization initiator, The second resin composition layer further contains (D) an imidazole compound, The content of the imidazole compound (D) in the first resin composition layer is 0 to 0.4 mass%, A photosensitive multilayer resin film, wherein the content by mass of the imidazole compound (D) in the first resin composition layer is less than the content by mass of the imidazole compound (D) in the second resin composition layer.

2. The photosensitive multilayer resin film according to claim 1, wherein the content of the imidazole compound (D) in the second resin composition layer is 0.1 to 5 mass %.

3. The photosensitive multilayer resin film according to claim 1, wherein the first resin composition layer and the second resin composition layer each contain, as the compound (A) having an ethylenically unsaturated group, (A1) a compound having an ethylenically unsaturated group and an acidic substituent.

4. 2. The photosensitive multilayer resin film according to claim 1, wherein the first resin composition layer and the second resin composition layer each contain, as the (B) thermosetting resin, one or more selected from the group consisting of epoxy resins, maleimide resins, allyl resins, and vinyl resins.

5. 2. The photosensitive multilayer resin film according to claim 1, wherein the first resin composition layer and the second resin composition layer each contain an epoxy resin as the (B) thermosetting resin, and the content of the epoxy resin in the first resin composition layer on a mass basis is greater than the content of the epoxy resin in the second resin composition layer on a mass basis.

6. 2. The photosensitive multilayer resin film according to claim 1, wherein the content of the fluorine-containing resin (I) is 10% by mass or less based on the total amount of resin components in the photosensitive multilayer resin film.

7. The photosensitive multilayer resin film according to claim 1, wherein the layer formed by curing the first resin composition layer is a layer on which a circuit pattern is formed by copper plating, and the second resin composition layer is a layer having a surface to be attached when laminating the photosensitive multilayer resin film.

8. The photosensitive multilayer resin film according to claim 1 , which is used for forming an interlayer insulating layer having a photovia.

9. A printed wiring board having an interlayer insulating layer which is a cured product of the photosensitive multilayer resin film according to claim 1.

10. A semiconductor package comprising the printed wiring board according to claim 9.

11. A method for producing a printed wiring board, comprising the following (1) to (4): (1): The photosensitive multilayer resin film according to any one of claims 1 to 8 is laminated onto one or both sides of a circuit board, with the second resin composition layer serving as an attachment surface. (2) Forming an interlayer insulating layer having vias by exposing and developing the photosensitive multilayer resin film laminated in (1) above. (3): Heating and curing the interlayer insulating layer having the vias. (4): Forming a circuit pattern on the layer obtained by curing the first resin composition layer of the interlayer insulating layer.

Images