WO2023190811A1

WO2023190811A1 - Photosensitive multilayer resin film, printed wiring board, semiconductor package, and printed wiring board manufacturing method

Info

Publication number: WO2023190811A1
Application number: PCT/JP2023/013060
Authority: WO
Inventors: 友洋鮎ヶ瀬; 憂子今野; 諒雪岡
Original assignee: 株式会社レゾナック
Priority date: 2022-03-31
Filing date: 2023-03-30
Publication date: 2023-10-05
Also published as: TW202400690A; WO2023188296A1

Abstract

The present invention pertains to a photosensitive multilayer resin film comprising a first resin composition layer and a second resin composition layer. The first resin composition layer and the second resin composition layer each contain a compound (A) having an ethylenically unsaturated group, a thermosetting resin (B), a photoinitiator (C), and an inorganic filler (D). The first resin composition layer contains silica as the inorganic filler (D). The second resin composition layer further contains a fluorine-containing resin (E). The silicon atom concentration in the first resin composition layer is higher than the silicon atom concentration in the second resin composition layer.

Description

Method for manufacturing photosensitive multilayer resin film, printed wiring board, semiconductor package, and printed wiring board

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

In recent years, electronic devices have become smaller and more sophisticated, and printed wiring boards are becoming more dense due to an increase in the number of circuit layers, miniaturization of wiring, etc. 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 becoming remarkable. Therefore, printed wiring boards are required to have thinner interlayer insulating layers and smaller diameter vias for interlayer connections, in addition to finer wiring.

As a conventional method for manufacturing printed wiring boards, there is a method for manufacturing multilayer printed wiring boards using a build-up method (for example, see Patent Document 1) in which an interlayer insulating layer and a conductor circuit layer are sequentially laminated. . With the miniaturization of circuits in multilayer printed wiring boards, semi-additive construction methods in which circuits are formed by plating have become mainstream. In conventional semi-additive construction methods, thermosetting resin films have been used to form interlayer insulation layers.

Laser processing is the mainstream method for forming vias in an interlayer insulating layer formed of a thermosetting resin film. However, reduction in the diameter of vias by laser processing is reaching its limit. Furthermore, when forming vias by laser processing, it is necessary to form each via hole one by one. Therefore, when it is necessary to form a large number of vias due to high density, there are problems in that it takes a lot of time to form the vias, the manufacturing cost is high, and the manufacturing efficiency is poor.

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).

Japanese Patent Application Publication No. 7-304931 JP 2017-116652 Publication

Incidentally, in recent years, the speed and capacity of signals used in electronic devices has been increasing year by year. Along with this, substrate materials for printed wiring boards have dielectric properties [hereinafter sometimes referred to as "high frequency properties"] that can reduce transmission loss of high frequency signals. ], that is, a low dielectric constant and a low dielectric loss tangent are required.

The present inventors have considered incorporating a fluorine-containing resin with a low dielectric constant into a photosensitive resin film for forming an interlayer insulating layer in order to improve the dielectric properties of the substrate material. However, if a fluorine-containing resin is simply added to a photosensitive resin film, even if the dielectric constant of the interlayer insulation layer can be reduced, there is a problem in that the adhesion of the conductor, especially the adhesion strength with plated copper, decreases. occured. Therefore, it has been difficult to achieve both excellent dielectric properties and conductor adhesion.

In view of the current situation, the present embodiment provides a photosensitive multilayer resin film capable of forming an interlayer insulating layer having excellent dielectric properties and conductor adhesion, a printed wiring board using the photosensitive multilayer resin film, and a method for manufacturing the same. and to provide semiconductor packages.

The present inventors conducted studies to solve the above problems, and as a result, they found that the above problems could be solved by the present embodiment described below.
That is, the present embodiment relates to the following [1] to [15].
[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, (C) a photopolymerization initiator, and (D) an inorganic filler;
The first resin composition layer contains silica as the (D) inorganic filler,
The second resin composition layer further contains (E) a fluorine-containing resin,
A photosensitive multilayer resin film, wherein the silicon atom concentration in the first resin composition layer is higher than the silicon atom concentration in the second resin composition layer.
[2] The first resin composition layer and the second resin composition layer each have an ethylenically unsaturated group and an acidic substituent as the (A) ethylenically unsaturated group-containing compound. The photosensitive multilayer resin film according to [1] above, which contains.
[3] In the first resin composition layer and the second resin composition layer, the thermosetting resin (B) is each selected from the group consisting of an epoxy resin, a maleimide resin, an allyl resin, and a vinyl resin. The photosensitive multilayer resin film according to [1] or [2] above, containing one or more of the above.
[4] The first resin composition layer and the second resin composition layer each contain an epoxy resin as the (B) thermosetting resin, and The photosensitive multilayer resin film according to [3] above, wherein the content of the epoxy resin on a mass basis is greater than the content of the epoxy resin on a mass basis in the second resin composition layer.
[5] The photosensitive multilayer resin film according to any one of [1] to [4] above, wherein the silica content in the first resin composition layer is 5 to 70% by mass.
[6] Any one of [1] to [5] above, wherein the second resin composition layer contains silica having a true density of 1,500 kg/m ³ or less as (D) an inorganic filler. The photosensitive multilayer resin film described above.
[7] The content of the fluorine-containing resin (E) in the second resin composition layer is 10 to 70% by mass, based on the total amount of resin components in the second resin composition layer. The photosensitive multilayer resin film according to any one of [1] to [6].
[8] The photosensitive material according to any one of [1] to [7] above, wherein the first resin composition layer and the second resin composition layer each further contain (F) an elastomer. Multilayer resin film.
[9] The photosensitive multilayer resin film according to any one of [1] to [8] above, wherein the content of the inorganic filler (D) in the second resin composition layer is less than 60% by mass. .
[10] The ratio of the silicon atom concentration in the first resin composition layer to the silicon atom concentration in the second resin composition layer [(first layer)/(second layer)] is 1.1. -15, the photosensitive multilayer resin film according to any one of [1] to [9] above.
[11] 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 formed by laminating the photosensitive multilayer resin film. The photosensitive multilayer resin film according to any one of [1] to [10] above, which is a layer having a surface to which it is attached when it is attached.
[12] The photosensitive multilayer resin film according to any one of [1] to [11] above, which is used for forming an interlayer insulating layer having photovias.
[13] A printed wiring board having an interlayer insulating layer that is a cured product of the photosensitive multilayer resin film according to any one of [1] to [12] above.
[14] A semiconductor package comprising the printed wiring board according to [13] above.
[15] A method for manufacturing a printed wiring board, including the following (1) to (4).
(1): Laminating the photosensitive multilayer resin film according to any one of [1] to [12] above on one or both sides of a circuit board, with the second resin composition layer serving as the attachment surface. thing.
(2): Forming an interlayer insulating layer having vias by exposing and developing the photosensitive multilayer resin film laminated in (1) above.
(3): Curing the interlayer insulating layer having the via by heating.
(4): Forming a circuit pattern on a layer formed by curing the first resin composition layer of the interlayer insulating layer.

According to the present embodiment, a photosensitive multilayer resin film capable of forming an interlayer insulating layer having excellent dielectric properties and conductor adhesion, a printed wiring board using the photosensitive multilayer resin film, a method for manufacturing the same, and a semiconductor package are provided. can do.

FIG. 2 is a schematic diagram showing one aspect of the manufacturing process of a printed wiring board using the photosensitive multilayer resin film of the present embodiment as a material for an interlayer insulating layer. It is a cross-sectional SEM image for explaining the measurement position of silicon atom concentration.

In the numerical ranges described in this specification, the lower limit and upper limit of the numerical range may be replaced with the values shown in the examples. Further, the lower limit value and upper limit value of the numerical range can be arbitrarily combined with the lower limit value or upper limit value of other numerical ranges, respectively. In the notation 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 limit value and upper limit value, respectively.

In this specification, for example, the expression "10 or more" means 10 and a numerical value exceeding 10, and the same applies even if the numerical values are different. Further, for example, the description "10 or less" means 10 and a numerical value less than 10, and this applies even if the numerical values are different.

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

As used herein, "solid content" means non-volatile content excluding volatile substances such as solvents. That is, "solid content" refers to components that remain without being volatilized when the resin composition is dried, and includes components that are liquid, starch syrup-like, and wax-like at room temperature. Here, in this specification, room temperature means 25°C.

As used herein, the "number of carbon atoms forming a ring" is the number of carbon atoms necessary to form a ring, and does not include the number of carbon atoms of substituents that the ring has. For example, both the cyclohexane skeleton and the methylcyclohexane skeleton have 6 ring carbon atoms.

The expression "(meth)acrylic XX" means one or both of acrylic XX and the corresponding methacryl XX. Moreover, "(meth)acryloyl group" means one or both of an acryloyl group and a methacryloyl group.

In this specification, when the word "layer" is used, for example, an interlayer insulating layer, etc., it may be a solid layer, a part of the layer may be island-shaped, or a hole may be formed. A "layer" also includes an open embodiment and an embodiment in which the interface with an adjacent layer is unclear.

The mechanism of action described in this specification is speculative and does not limit the mechanism by which the effects of this embodiment are produced.

This embodiment also includes aspects in which the items described in this specification are arbitrarily combined.

[Photosensitive multilayer resin film]
The photosensitive multilayer resin film of this embodiment is
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, (C) a photopolymerization initiator, and (D) an inorganic filler;
The first resin composition layer contains silica as the (D) inorganic filler,
The second resin composition layer further contains (E) a fluorine-containing resin,
The silicon atom concentration in the first resin composition layer is higher than the silicon atom concentration in the second resin composition layer.
It is a photosensitive multilayer resin film.

Note that, in this specification, each component may be abbreviated as "component (A)", "component (B)", etc. as appropriate.

The first resin composition layer and the second resin composition layer included in the photosensitive multilayer resin film of this embodiment can form patterns such as vias by exposure and development. Therefore, the photosensitive multilayer resin film of this embodiment is suitable for forming an interlayer insulating layer having photovias. Note that in this specification, "photovia" means a via formed by a photolithography method, that is, exposure and development.

The first resin composition layer contains (A) a compound having an ethylenically unsaturated group, (B) a thermosetting resin, (C) a photopolymerization initiator, and (D) an inorganic filler; ) Contains silica as an inorganic filler.
The silicon atom concentration in the first resin composition layer is higher than the silicon atom concentration in the second resin composition layer. As a result, the layer formed by curing the first resin composition layer has a good anchor formed on its surface by the roughening treatment step before forming the plated copper, and exhibits high adhesive strength with the plated copper.

The second resin composition layer includes (A) a compound having an ethylenically unsaturated group, (B) a thermosetting resin, (C) a photopolymerization initiator, (D) an inorganic filler, and (E) a fluorine-containing resin. Contains. Since the fluorine-containing resin (E) contained in the second resin composition layer has a small dielectric constant, the layer formed by curing the second resin composition layer contributes to improving the dielectric properties of the interlayer insulation layer. do.

As described above, the photosensitive multilayer resin film of this embodiment has a first resin composition layer that exhibits high adhesive strength with plated copper, and a second resin composition layer that exhibits excellent dielectric properties. , it is possible to form an interlayer insulating layer having excellent dielectric properties and conductor adhesion. From the viewpoint of fully expressing the effect, the photosensitive multilayer resin film of this embodiment is such that the layer formed by curing the first resin composition layer is a layer in which a circuit pattern is formed by copper plating, It is preferable that the second resin composition layer is a layer having a surface to which it is attached when laminating the photosensitive multilayer resin film.

The thickness of the first resin composition layer is not particularly limited, but from the viewpoint of achieving a better balance between dielectric properties and conductor adhesion, it is preferably 0.1 to 50 μm, more preferably 0.5 to 30 μm. , more preferably 1 to 10 μm.
The thickness of the second resin composition layer is not particularly limited, but from the viewpoint of achieving a better balance between dielectric properties and conductor adhesion, the thickness is preferably 1 to 100 μm, more preferably 3 to 50 μm, and even more preferably It is 5 to 40 μm.
The overall thickness of the photosensitive multilayer resin film of this embodiment is not particularly limited, and may be, for example, 2 to 110 μm, 4 to 60 μm, or 7 to 50 μm.

<Silicon atom concentration>
In the photosensitive multilayer resin film of this embodiment, the silicon atom concentration in the first resin composition layer (hereinafter also referred to as "first layer silicon atom concentration") is the same as that in the second resin composition layer. higher than the silicon atom concentration (hereinafter also referred to as "second layer silicon atom concentration").
The silicon atom concentration of the first layer is not particularly limited, but from the viewpoint of forming an interlayer insulating layer with better dielectric properties and conductor adhesion, it is preferably 2 to 35% by mass, more preferably 4 to 30% by mass, and more preferably 4 to 30% by mass. Preferably it is 6 to 25% by mass.
The silicon atom concentration in the second layer is not particularly limited as long as it is lower than the silicon atom concentration in the first layer, but from the viewpoint of forming an interlayer insulating layer with better dielectric properties and conductor adhesion, The range lower than the concentration is preferably 0.5 to 15% by weight, more preferably 1 to 10% by weight, and even more preferably 2 to 7% by weight.
The ratio of the silicon atom concentration in the first layer to the silicon atom concentration in the second layer [(first layer)/(second layer)] is not particularly limited, but forms an interlayer insulating layer with better dielectric properties and conductor adhesion. From the viewpoint of achieving this, the mass ratio is preferably 1.1 to 15, more preferably 1.5 to 10, and even more preferably 2 to 8.
Although the method for measuring the silicon atom concentration in each layer is not particularly limited, for example, it can be measured by forming a cross section of a photosensitive multilayer resin film or a cured product thereof and performing elemental analysis of the cross section. can. More specifically, it can be measured by the method described in Examples.

Each component contained in the first resin composition layer and the second resin composition layer will be explained below.
In addition, among the explanations regarding components (A) to (I) below, explanations regarding preferred embodiments of the components that can be included in both the first resin composition layer and the second resin composition layer are the same as those in the section 1, unless otherwise specified. This is common to the first resin composition layer and the second resin composition layer.
Further, 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 or different. 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 or different. . The same applies to components (B) to (I).

<(A) Compound having an ethylenically unsaturated group>
Component (A) is not particularly limited as long as it is a compound having an ethylenically unsaturated group.
Component (A) may be used alone or in combination of two or more.

Component (A) is a compound that exhibits photopolymerizability, particularly radical polymerization, because it has an ethylenically unsaturated group.
In addition, in this specification, "ethylenic unsaturated group" means a substituent containing an ethylenically unsaturated bond. Furthermore, the term "ethylenically unsaturated bond" means a carbon-carbon double bond capable of 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, and a nadimide group. Among these, a (meth)acryloyl group is preferred from the viewpoint of reactivity.

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

<(A1) Compound having an ethylenically unsaturated group and an acidic substituent>
Examples of the acidic substituent that component (A1) has include a carboxy group, a sulfonic acid group, and a phenolic hydroxyl group. Among these, a carboxy group is preferred from the viewpoint of resolution.
The acid value of component (A1) is not particularly limited, but is preferably 20 to 200 mgKOH/g, more preferably 40 to 180 mgKOH/g, and even more preferably 70 to 150 mgKOH/g.
When the acid value of the component (A1) is at least the above lower limit, the alkali developability tends to be better. Moreover, when the acid value of the component (A1) is below the above upper limit, the dielectric constant tends to be better.
Note that the acid value of component (A1) can be measured by the method described in Examples.

The weight average molecular weight (Mw) of component (A1) is not particularly limited, but 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 superior in adhesive strength to plated copper, 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 to standard polystyrene. This is a value measured according to the method described.

The component (A1) preferably contains an alicyclic skeleton from the viewpoint of low relative permittivity and low dielectric loss tangent.
From the viewpoint of resolution and dielectric properties, the alicyclic skeleton of component (A1) is preferably an alicyclic skeleton having 5 to 20 ring carbon atoms, and an alicyclic skeleton having 5 to 18 ring carbon atoms. is more preferred, an alicyclic skeleton having 6 to 16 ring carbon atoms is even more preferred, an alicyclic skeleton having 7 to 14 ring carbon atoms is particularly preferred, and an alicyclic skeleton having 8 to 12 ring carbon atoms is most preferred. preferable.

From the viewpoint of resolution and dielectric properties, the alicyclic skeleton of component (A1) preferably consists of 2 or more rings, more preferably 2 to 4 rings, and even more preferably 3 rings. . Examples of the alicyclic skeleton consisting of two or more rings include a norbornane skeleton, a decalin skeleton, a bicycloundecane skeleton, and a saturated dicyclopentadiene skeleton. Among these, a saturated dicyclopentadiene skeleton is preferred from the viewpoint of resolution and dielectric properties.
From the same viewpoint, component (A1) preferably contains an alicyclic skeleton represented by the following general formula (A1-1).

(In the formula, R ^A1 represents an alkyl group having 1 to 12 carbon atoms, and may be substituted anywhere in the alicyclic skeleton. m ¹ is an integer of 0 to 6. * indicates a bonding site. .)

In the above general formula (A1-1), examples of the alkyl group having 1 to 12 carbon atoms represented by R ^A1 include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t -butyl group, n-pentyl group, etc. The alkyl group is preferably an alkyl group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and even more preferably a methyl group.

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. When m ¹ is an integer of 2 to 6, the plurality of R ^A1s may be the same or different. Furthermore, a plurality of R ^A1s may be substituted on the same carbon atom or different carbon atoms to the extent possible.

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

(In the formula, R ^A1 , m ¹ and * are the same as in the above general formula (A1-1).)

Component (A1) is a compound obtained by reacting (a1) an epoxy resin with (a2) a (meth)acryloyl group-containing organic acid, and (a3) a saturated or unsaturated group-containing polybasic acid anhydride. Preferably, it is a compound obtained by
In the following description, a compound obtained by reacting (a1) an epoxy resin and (a2) a (meth)acryloyl group-containing organic acid may be referred to as "component (A')."
In addition, a compound obtained by reacting component (A') with (a3) a polybasic acid anhydride containing a saturated group or an unsaturated group may be referred to as an "acid-modified (meth)acryloyl group-containing epoxy resin derivative." be.
Hereinafter, preferred embodiments of component (A1) will be described.

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

(a1) Epoxy resins are classified into, for example, glycidyl ether type epoxy resins, glycidylamine type epoxy resins, glycidyl ester types, and the like. Among these, glycidyl ether type epoxy resins are preferred.

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

[Epoxy resin with alicyclic skeleton]
The alicyclic skeleton possessed by the epoxy resin having an alicyclic skeleton is explained in the same manner as the alicyclic skeleton possessed by the component (A1) described above, and the 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.

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

In the above general formula (A1-2), R ^A1 is the same as R ^A1 in the above general formula (A1-1), and the preferred embodiments are also the same.
Examples of the alkyl group having 1 to 12 carbon atoms represented by R ^A2 in the above general formula (A1-2) include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t -butyl group, n-pentyl group, etc. The alkyl group is preferably an alkyl group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and even more preferably a methyl group.
m ¹ in the above general formula (A1-2) is the same as m ¹ in the above general formula (A1-1), and the preferred embodiments are also the same.
m ² in the above general formula (A1-2) is an integer of 0 to 3, preferably 0 or 1, and more preferably 0.
n in the above general formula (A1-2) represents the number of structural units in parentheses, and is a number from 0 to 50. Usually, epoxy resins are a mixture of different numbers of structural units in parentheses, so in that case, n is expressed as the average value of the mixture. As n, a number from 0 to 30 is preferable.

As the epoxy resin having an alicyclic skeleton, commercially available products may be used, such as "ZXR-1807H" (manufactured by Nippon Kayaku Co., Ltd., trade name), "XD-1000" ( Nippon Kayaku Co., Ltd., trade name) and "EPICLON (registered trademark) HP-7200" (DIC Corporation, trade name).

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

(In the formula, R ^A3 each independently represents a hydrogen atom or a methyl group, and Y ^A1 each independently represents a hydrogen atom or a glycidyl group. At least one of the two Y ^A1 is a glycidyl group. .)

From the viewpoint of resolution, R ^A3 in the above general formula (A1-3) is preferably a hydrogen atom. From the same viewpoint, Y ^A1 in the above general formula (A1-3) is preferably a glycidyl group.

The number of structural units in the epoxy resin (a1) having the structural unit represented by the above general formula (A1-3) is 1 or more, preferably 10 to 100, more preferably 13 to 80. , more preferably a number of 15 to 70. When the number of structural units is within the above range, it tends to be possible to form an interlayer insulating layer that has better conductor adhesion, heat resistance, and insulation reliability.

As the epoxy resin having the structural unit represented by the above general formula (A1-3), commercially available products may be used. In the above general formula (A1-3), R ^A3 are all hydrogen atoms and Y ^A1 are all glycidyl groups (epoxy resin), "EPON SU8" series (manufactured by Mitsubishi Chemical Corporation, product name, In the above general formula (A1-3), all R ^A3 are methyl groups, and all Y ^A1 are glycidyl groups.

[Bisphenol type epoxy resin]
Examples of bisphenol type epoxy resins include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, 3,3',5,5'-tetramethyl-4,4'-diglycidyloxydiphenylmethane, etc. can be mentioned.

[Aralkyl type epoxy resin]
Examples of aralkyl-type epoxy resins include phenolaralkyl-type epoxy resins, biphenylaralkyl-type epoxy resins, naphtholaralkyl-type epoxy resins, and the like.

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

((a2) (meth)acryloyl group-containing organic acid)
(a2) As the (meth)acryloyl group-containing organic acid, a (meth)acryloyl group-containing monocarboxylic acid is preferable.
(Meth)acryloyl group-containing monocarboxylic acids include, for example, acrylic acid, acrylic acid dimer, methacrylic acid, β-furfurylacrylic acid, β-styrylacrylic acid, cinnamic acid, crotonic acid, α-cyanocinnamic acid. Acrylic acid derivatives such as acids; half-ester compounds that are reaction products of hydroxyl group-containing acrylates and dibasic acid anhydrides; (meth)acryloyl group-containing monoglycidyl ethers or (meth)acryloyl group-containing monoglycidyl esters and dibasic acids Examples include half-ester compounds that are reaction products with anhydrides.
Component (a2) may be used alone or in combination of two or more.

In the reaction between component (a1) and component (a2), the amount of component (a2) to be used is not particularly limited, but is preferably 0.6 to 1.1 per equivalent of epoxy group in component (a1). equivalent, more preferably 0.8 to 1.05 equivalent, still more preferably 0.9 to 1.02 equivalent. By reacting the component (a1) and the component (a2) in the above ratio, the polymerizability of the component (A1) tends to improve, and the resolution tends to improve.

It is preferable that the components (a1) and (a2) are dissolved in an organic solvent and reacted while being heated. Moreover, when making it react, you may use a well-known reaction catalyst, a polymerization inhibitor, etc. as needed.

When a (meth)acryloyl group-containing monocarboxylic acid is used as the component (a2), the component (A') obtained by reacting the component (a1) and the component (a2) is the epoxy group of the component (a1). It has a hydroxyl group formed by a ring-opening addition reaction with the carboxy group of component (a2). Next, by reacting the component (A') with the saturated or unsaturated group-containing polybasic acid anhydride (a3), the hydroxyl group of the component (A') and the acid anhydride group of the component (a3) are combined. An acid-modified (meth)acryloyl group-containing epoxy resin derivative in which is half-esterified is obtained. Note that the hydroxyl group possessed by the component (A') may also include the hydroxyl group originally present in the component (a1).

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

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

<(A2) Monomer having two or more ethylenically unsaturated groups>
Component (A2) is mainly used as a crosslinking agent for component (A1).
By containing the (A2) component together with the (A1) component, the first resin composition layer and the second resin composition layer have an increased crosslinking density due to a photoradical polymerization reaction, and improve alkaline developer resistance and resolution. It tends to be possible to form an interlayer insulating layer with improved heat resistance and better heat resistance.
Note that component (A2) may or may not have an acidic substituent.

The number of ethylenically unsaturated groups contained in component (A2) is 2 or more, preferably 2 to 10 from the viewpoint of resolution and from the viewpoint of forming an interlayer insulating layer with better heat resistance and dielectric properties. , more preferably 2 to 8 pieces, still more preferably 2 to 7 pieces.

Examples of the component (A2) include bifunctional monomers having two ethylenically unsaturated groups, polyfunctional monomers having three or more ethylenically unsaturated groups, and the like.

Examples of difunctional 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. Acrylate; di(meth)acrylate having an alicyclic skeleton such as dicyclopentadiene di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate; 2,2-bis(4-(meth)acryloxypolyethoxy) Examples include aromatic di(meth)acrylates such as polypropoxyphenyl)propane and bisphenol A diglycidyl ether di(meth)acrylate.

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; tetramethylolmethane tri(meth)acrylate; (Meth)acrylate compounds having a skeleton derived from tetramethylolmethane such as acrylate and tetramethylolmethanetetra(meth)acrylate; having a skeleton derived from pentaerythritol such as pentaerythritol tri(meth)acrylate and pentaerythritol tetra(meth)acrylate (meth)acrylate compounds; (meth)acrylate compounds having a skeleton derived from dipentaerythritol, such as dipentaerythritol penta(meth)acrylate and dipentaerythritol hexa(meth)acrylate; ditrimethylolpropane tetra(meth)acrylate, etc. Examples include (meth)acrylate compounds having a skeleton derived from methylolpropane; (meth)acrylate compounds having a skeleton derived from diglycerin; and the like.
Here, the above-mentioned "(meth)acrylate compound having a skeleton derived from XXX" (where XXX is the compound name) means an esterified product of XXX and (meth)acrylic acid, and the esterified product also includes compounds modified with alkyleneoxy groups.

Among the above options, component (A2) is preferably a polyfunctional monomer having three or more ethylenically unsaturated groups, from the viewpoint of resolution and from the viewpoint of forming an interlayer insulating layer with better conductor adhesion. , (meth)acrylate compounds having a skeleton derived from trimethylolpropane, and (meth)acrylate compounds having a skeleton derived from dipentaerythritol are more preferred.

Component (A) may or may not contain compounds other than the components (A1) and (A2). Examples of components other than component (A1) and component (A2) include monofunctional monomers having one ethylenically unsaturated group and no acidic substituent.

(Content of component (A) in first resin composition layer)
The content of component (A) in the first resin composition layer is not particularly limited, but from the viewpoint of the resolution of the photosensitive multilayer resin film and the dielectric properties of the interlayer insulating layer to be formed, the content of the component (A) in the first resin composition layer is Based on the total amount of resin components in the composition layer, it is preferably 10 to 80% by mass, more preferably 20 to 60% by mass, and even more preferably 30 to 50% by mass.
Here, in this specification, the "resin component" means a resin and a compound that forms a resin through a curing reaction. For example, in the photosensitive multilayer resin film of this embodiment, the (A) component, (B) component, (E) component, and (F) component are classified as resin components.
On the other hand, the (C) component, (D) component, (G) component, and (H) component shall not be included in the resin component.

When the first resin composition layer contains component (A1), the content of component (A1) in the first resin composition layer is not particularly limited; From the viewpoint of dielectric properties, the amount is preferably 5 to 70% by mass, more preferably 10 to 50% by mass, and even more preferably 20 to 40% by mass, based on the total amount of resin components in the first resin composition layer.

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 not particularly limited; From the viewpoint of dielectric properties of the interlayer insulating layer, preferably 5 to 80 parts by mass, more preferably 10 to 60 parts by mass, and Preferably it is 20 to 40 parts by mass.

(Content of component (A) in second resin composition layer)
The content of component (A) in the second resin composition layer is not particularly limited, but from the viewpoint of resolution and dielectric properties of the interlayer insulating layer to be formed, the content of the component (A) in the second resin composition layer is Based on the total amount of components, it is preferably 10 to 80% by weight, more preferably 20 to 60% by weight, and even more preferably 30 to 50% by weight.

When the second resin composition layer contains component (A1), the content of component (A1) in the second resin composition layer is not particularly limited; From the viewpoint of dielectric properties, the amount is preferably 5 to 60% by mass, more preferably 10 to 40% by mass, and even more preferably 15 to 30% by mass, based on the total amount of resin components in the second resin composition layer.

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 not particularly limited; From the viewpoint of dielectric properties of the interlayer insulating layer, preferably 20 to 100 parts by mass, more preferably 40 to 90 parts by mass, and Preferably it is 60 to 80 parts by mass.

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

(B) Thermosetting resins include, for example, epoxy resins, isocyanate resins, maleimide resins, phenol resins, cyanate resins, benzoxazine resins, oxetane resins, amino resins, unsaturated polyester resins, allyl resins, vinyl resins, dicyclo Examples include pentadiene resin, silicone resin, triazine resin, melamine resin, and other known thermosetting resins.

Among the above options, the first resin composition layer and the second resin composition layer are each made of epoxy as the component (B) from the viewpoint of forming an interlayer insulating layer with better heat resistance and conductor adhesion. It is preferable to contain one or more selected from the group consisting of a resin, a maleimide resin, an allyl resin, and a vinyl resin, and it is more preferable to contain an epoxy resin.
Further, it is also preferable that the second resin composition layer contains a maleimide resin from the viewpoint of forming an interlayer insulating layer having better heat resistance and conductor adhesion.

(Epoxy resin)
As the epoxy resin, an epoxy resin having two or more epoxy groups is preferable.
Epoxy resins are classified into, for example, glycidyl ether type epoxy resins, glycidyl amine type epoxy resins, glycidyl ester type epoxy resins, and the like. Among these, glycidyl ether type epoxy resins are preferred.

Furthermore, epoxy resins are classified into various epoxy resins based on differences in their main skeletons, and each of the above-mentioned types of epoxy resins is further classified as follows. Specifically, the epoxy resin includes, for example, bisphenol epoxy resins such as bisphenol A epoxy resin, bisphenol F epoxy resin, and bisphenol S epoxy resin; bisphenol A novolac epoxy resin, bisphenol F novolac epoxy resin, etc. Bisphenol-based novolak-type epoxy resin; Novolak-type epoxy resin other than the above-mentioned bisphenol-based novolak-type epoxy resin, such as phenol novolac-type epoxy resin, cresol novolac-type epoxy resin, biphenyl novolak-type epoxy resin; Phenol-aralkyl-type epoxy resin; Stilbene-type epoxy resin Resin; Naphthalene skeleton-containing epoxy resins such as naphthol novolac type epoxy resins, naphthol type epoxy resins, naphthol aralkyl type epoxy resins, naphthylene ether type epoxy resins; biphenyl type epoxy resins; biphenylaralkyl type epoxy resins; xylylene type epoxy resins; dihydro Anthracene type epoxy resin; alicyclic epoxy resin such as saturated dicyclopentadiene type epoxy resin; heterocyclic epoxy resin; spiro ring-containing epoxy resin; cyclohexanedimethanol type epoxy resin; trimethylol type epoxy resin; aliphatic chain epoxy It is classified into resin; rubber-modified epoxy resin; etc.

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.

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

(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, and the like. Among these, aromatic maleimide compounds are preferred, and aromatic bismaleimide compounds are more preferred, from the viewpoint of heat resistance and handleability.
Examples of aromatic maleimide compounds include bis(4-maleimidophenyl)methane, 2,2-bis[4-(4-maleimidophenoxy)phenyl]propane, 3,3'-dimethyl-5,5'-diethyl- Examples include 4,4'-diphenylmethane bismaleimide, polyphenylmethane maleimide, biphenylaralkyl maleimide resin, and aromatic bismaleimide resin having an indane skeleton. Among these, aromatic bismaleimide resins having an indane skeleton are preferred.

(Content of component (B) in first resin composition layer)
The content of the thermosetting resin (B) in the first resin composition layer is not particularly limited, but from the viewpoint of forming an interlayer insulating layer with better conductor adhesion and heat resistance, the content of the first resin composition layer is Based on the total amount of resin components in the layer, it is preferably 10 to 90% by weight, more preferably 20 to 80% by weight, and still more preferably 30 to 70% by weight.

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 not particularly limited, but the conductor adhesiveness and From the viewpoint of forming an interlayer insulating layer with better heat resistance, preferably 7 to 80% by mass, more preferably 15 to 70% by mass, even more preferably 20% by mass, based on the total amount of resin components in the first resin composition layer. ~60% by mass.
The content of the epoxy resin on a mass basis in the first resin composition layer is determined from the viewpoint of forming an interlayer insulating layer with better conductor adhesion. It is preferable that the content is greater than the content of .

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 not particularly limited, but the conductor adhesiveness and From the viewpoint of forming an interlayer insulating layer with better heat resistance, preferably 1 to 30% by mass, more preferably 3 to 20% by mass, even more preferably 5% by mass, based on the total amount of resin components in the first resin composition layer. ~15% by mass.

(Content of component (B) in second resin composition layer)
The content of the thermosetting resin (B) in the second resin composition layer is not particularly limited, but from the viewpoint of forming an interlayer insulating layer with better heat resistance and dielectric properties, the content of the thermosetting resin (B) in the second resin composition layer is The amount is preferably 1 to 50% by weight, more preferably 10 to 40% by weight, and even more preferably 20 to 30% by weight, based on the total amount of resin components in the resin.

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 not particularly limited, but From the viewpoint of forming an interlayer insulating layer with better properties, preferably 1 to 50% by mass, more preferably 5 to 30% by mass, even more preferably 7 to 30% by mass, based on the total amount of resin components in the second resin composition layer. It is 25% by mass.

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 not particularly limited, but it is suitable for heat resistance and dielectric properties. From the viewpoint of forming an interlayer insulating layer with more excellent properties, preferably 1 to 20% by mass, more preferably 2 to 15% by mass, even more preferably 4 to 15% by mass, based on the total amount of resin components in the second resin composition layer. It is 10% by mass.

When the second resin composition layer contains a maleimide resin as the thermosetting resin (B), the content of the maleimide resin in the second resin composition layer is not particularly limited, but From the viewpoint of forming an interlayer insulating layer with more excellent properties, preferably 1 to 40% by mass, more preferably 3 to 30% by mass, still more preferably 5 to 30% by mass, based on the total amount of resin components in the second resin composition layer. It is 20% by mass.

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

(C) Photopolymerization initiators include, for example, benzoin compounds such as benzoin, benzoin methyl ether, and benzoin isopropyl ether; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, and 2,2-diethoxy-2-phenylacetophenone. , 1,1-dichloroacetophenone, 1-hydroxycyclohexylphenylketone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, 2-[4-(methylthio)benzoyl]-2- Acetophenone compounds such as (4-morpholinyl)propane, N,N-dimethylaminoacetophenone; 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, 2-amino Anthraquinone compounds such as anthraquinone; ketal compounds such as acetophenone dimethyl ketal and benzyl dimethyl ketal; acridine compounds such as 9-phenylacridine and 1,7-bis(9,9'-acridinyl)heptane; phenylbis(2, Acyl phosphine oxide compounds such as 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), 1-phenyl-1,2-propanedione-2-[O-(ethoxycarbonyl)oxime] oxime ester compounds such as; thioxanthone compounds such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, and 2,4-diisopropylthioxanthone; 4,4'-bis(dimethylamino)benzophenone; Examples include benzophenone compounds such as 4,4'-bis(diethylamino)benzophenone. Among these, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone 1-(O-acetyl Oxime) is preferred.

(Content of component (C) in first resin composition layer)
The content of the photopolymerization initiator (C) in the first resin composition layer is not particularly limited, but from the viewpoint that it is easy to obtain an appropriate polymerization reaction promotion effect, The amount is preferably 0.01 to 10 parts by weight, more preferably 0.05 to 5 parts by weight, and even more preferably 0.1 to 1 part by weight, per 100 parts by weight of component (A).

(Content of component (C) in second resin composition layer)
The content of the photopolymerization initiator (C) in the second resin composition layer is not particularly limited, but from the viewpoint that it is easy to obtain an appropriate polymerization reaction promotion effect, The amount is preferably 0.01 to 10 parts by weight, more preferably 0.05 to 5 parts by weight, and even more preferably 0.1 to 1 part by weight, per 100 parts by weight of component (A).

<(D) Inorganic filler>
Since the first resin composition layer and the second resin composition layer contain (D) the inorganic filler, the formed interlayer insulating layer has further improved low thermal expansion, heat resistance, and flame retardancy. There is a tendency to
(D) Inorganic fillers may be used alone or in combination of two or more.

In the photosensitive multilayer resin film of this embodiment, the first resin composition layer contains silica as (D) an inorganic filler. As a result, the layer obtained by curing the first resin composition layer exhibits high adhesive strength with the plated copper.
Also, in the second resin composition layer, an interlayer insulating layer that has better low thermal expansion, heat resistance, and flame retardancy is provided in a range where the silicon atom concentration is lower than the silicon atom concentration in the first resin composition layer. It is preferable to contain silica from the viewpoint of forming.
The silica may be surface-treated with a coupling agent such as a silane coupling agent.

Examples of silica include precipitated silica that is produced by a wet process and has a high water content, and dry process silica that is produced by a dry process and contains almost no bound water. In addition, examples of the dry process silica include crushed silica, fumed silica, and fused silica, depending on the manufacturing method.

Examples of silica include (D1) silica with a true density of more than 1,500 kg/m ³ (hereinafter also referred to as "(D1) component"), (D2) silica with a true density of 1,500 kg/m ³ or less ( Hereinafter, it is also referred to as "component (D2)").

The (D1) component tends to have a low dielectric loss tangent. Therefore, from the viewpoint of forming an interlayer insulating layer with better dielectric properties, the first resin composition layer preferably contains the component (D1).
From the viewpoint of low thermal expansion, the true density of the silica component (D1) is preferably more than 1,500 and 2,200 kg/m ³ or less, more preferably 1,600 to 2,200 kg/m ³ , and even more preferably is 1,800 to 2,200 kg/ ^m3 .

Component (D2) tends to have a small dielectric constant. Therefore, from the viewpoint of forming an interlayer insulating layer with better dielectric properties, the second resin composition layer preferably contains the component (D2).
From the viewpoint of dielectric properties, the true density of the silica which is the component (D2) is preferably 1,000 to 1,500 kg/m ³ , more preferably 1,100 to 1,500 kg/m ³ , even more preferably 1, 200 to 1,500 kg/m ³ , particularly preferably 1,250 to 1,450 kg/m ³ and most preferably 1,250 to 1,400 kg/m ³ .
The true density of silica can be measured using a dry automatic density meter "AccuPycII 1340" (manufactured by Shimadzu Corporation).

Examples of (D) inorganic fillers other than silica include alumina, titanium oxide, mica, beryllia, barium titanate, potassium titanate, strontium titanate, calcium titanate, aluminum carbonate, magnesium hydroxide, aluminum hydroxide, Examples include aluminum silicate, calcium carbonate, calcium silicate, magnesium silicate, silicon nitride, boron nitride, clay, talc, aluminum borate, and silicon carbide.

(D) The volume average particle diameter (D ₅₀ ) of the inorganic filler is not particularly limited, but from the viewpoint of resolution, it is preferably 0.01 to 3.0 μm, more preferably 0.1 to 2.5 μm, More preferably, it is 0.3 to 2.0 μm.
Note that in this specification, the volume average particle diameter (D ₅₀ ) is defined as a refractive index of 1 using a submicron particle analyzer (manufactured by Beckman Coulter, Inc., trade name: N5) in accordance with the international standard ISO13321. .38, the particles dispersed in the solvent can be measured and determined as the particle diameter corresponding to an integrated value of 50% (volume basis) in the particle size distribution.

(Content of (D) inorganic filler in first resin composition layer)
The content of the (D) inorganic filler in the first resin composition layer is not particularly limited, but from the viewpoint of forming an interlayer insulating layer with low thermal expansion, heat resistance, flame retardance, and conductor adhesion. , preferably 5 to 70% by weight, more preferably 10 to 65% by weight, even more preferably 15 to 60% by weight.

The content of silica in the first resin composition layer is not particularly limited, but from the viewpoint of forming an interlayer insulating layer with low thermal expansion, heat resistance, flame retardance, and conductor adhesion, it is preferably 5 to 5. The content is 70% by weight, more preferably 10-65% by weight, even more preferably 15-60% by weight.
The content of silica in the first resin composition layer on a mass basis is determined from the viewpoint of forming an interlayer insulating layer with better conductor adhesion. It is preferable that the amount is greater than the amount.

When the first resin composition layer contains the (D1) component, the content of the (D1) component in the first resin composition layer is not particularly limited; D) With respect to the total amount (100 mass%) of the inorganic filler, preferably 60 to 100 mass%, More preferably 70 to 100% by mass, still more preferably 80 to 100% by mass.

(Content of (D) inorganic filler in second resin composition layer)
The content of the inorganic filler (D) in the second resin composition layer is not particularly limited, but from the viewpoint of forming an interlayer insulating layer with low thermal expansion, heat resistance, and flame retardance, it is preferably 60% Less than % by weight, more preferably 1-55% by weight, even more preferably 2-50% by weight, even more preferably 3-30% by weight, particularly preferably 5-20% by weight.

When the second resin composition layer contains silica, the content of silica in the second resin composition layer is not particularly limited, but is superior in low thermal expansion, heat resistance, flame retardancy, and conductor adhesion. From the viewpoint of forming an interlayer insulating layer, preferably less than 60% by mass, more preferably 1 to 55% by mass, even more preferably 2 to 50% by mass, even more preferably 3 to 30% by mass, particularly preferably 5 to 50% by mass. It is 20% by mass.

When the second resin composition layer contains component (D2), the content of component (D2) in the second resin composition layer is not particularly limited; From the viewpoint of forming an interlayer insulating layer with low thermal expansion, heat resistance, and flame retardance, based on the total amount (100% by mass) of component D), preferably 60 to 100% by mass, more preferably 70 to 100% by mass. % by mass, more preferably 80 to 100% by mass.

<(E) Fluorine-containing resin>
In the photosensitive multilayer resin film of this embodiment, (E) the fluorine-containing resin is contained in the second resin composition layer. As a result, the interlayer insulating layer formed from the photosensitive multilayer resin film of this embodiment tends to have a reduced dielectric constant.
(E) The fluorine-containing resins may be used alone or in combination of two or more.

(E) Examples of the fluorine-containing resin include polymers of olefins containing fluorine atoms (hereinafter also referred to as "fluorine-containing olefins").
The fluorine-containing olefin may be an olefin in which some of the hydrogen atoms in the carbon-hydrogen bonds are replaced with fluorine atoms, but from the viewpoint of further reducing the dielectric constant, all the hydrogen atoms in the carbon-hydrogen bonds are replaced with fluorine atoms. Olefins in which atoms are substituted by fluorine atoms are preferred.

(E) Examples of the fluorine-containing resin include polymonofluoroethylene, polydifluoroethylene, polytrifluoroethylene, polytetrafluoroethylene, polyhexafluoropropylene, polyvinyl fluoride, polyvinylidene fluoride, and the like. Among these, polytetrafluoroethylene is preferred.

(E) The fluorine-containing resin is preferably in the form of particles.
The volume average particle diameter (D ₅₀ ) of the fluorine-containing resin (E) is not particularly limited, but from the viewpoint of resolution, it is preferably 0.01 to 3.0 μm, more preferably 0.05 to 2 .5 μm, more preferably 0.1 to 2.0 μm.

(Content of component (E) in first resin composition layer)
The first resin composition layer may contain (E) a fluorine-containing resin, but from the viewpoint of resolution and forming an interlayer insulating layer with better conductor adhesion, (E) It is preferable not to contain a fluorine-containing resin.
When the first resin composition layer contains (E) a fluorine-containing resin, the content of the (E) fluorine-containing resin in the first resin composition layer is preferably as small as possible, and from the same viewpoint as above, Based on the total amount of resin components in the first resin composition layer, it is preferably 20% by mass or less, more preferably 10% by mass or less, and even more preferably 1% by mass or less.

(Content of component (E) in second resin composition layer)
The content of the (E) fluorine-containing resin in the second resin composition layer is not particularly limited, but from the viewpoint of resolution, as well as interlayer insulation that is superior in insulation reliability, dielectric constant, heat resistance, and conductor adhesion. From the viewpoint of forming a layer, it is preferably 10 to 70% by mass, more preferably 20 to 50% by mass, and even more preferably 25 to 40% by mass, based on the total amount of resin components in the second resin composition layer. .

<(F) Elastomer>
The first resin composition layer and the second resin composition layer may each further contain (F) an elastomer.
When the first resin composition layer and the second resin composition layer contain the (F) elastomer, the formed interlayer insulating layer tends to have further improved conductor adhesion.
The term "elastomer" as used herein means a polymer having a glass transition temperature of 25° C. or less as measured by differential scanning calorimetry according to JIS K 6240:2011.
(F) Elastomers may be used alone or in combination of two or more.

(F) Examples of the elastomer include polybutadiene elastomer, polyester elastomer, styrene elastomer, olefin elastomer, urethane elastomer, polyamide elastomer, acrylic elastomer, silicone elastomer, 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 with better conductor adhesion.

Preferred examples of the polybutadiene elastomer include those containing a 1,2-vinyl group 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 elastomer has an acid anhydride group, the number of acid anhydride groups in one molecule is not particularly limited, but from the viewpoint of resolution and from the viewpoint of forming an interlayer insulating layer with a higher dielectric constant. The number is preferably 1 to 12, more preferably 3 to 11, and even more preferably 6 to 10.

(F) The number average molecular weight (Mn) of the elastomer is not particularly limited, but preferably 1,000 to 100,000, more preferably 2,000 to 50,000, even more preferably 3,000 to 10,000, Particularly preferably 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 to standard polystyrene. This is a value measured according to the method described.

(Content of component (F) in first resin composition layer)
When the first resin composition layer contains the (F) elastomer, the content of the (F) elastomer in the first resin composition layer is not particularly limited, but the interlayer insulation is superior in heat resistance and conductor adhesion. From the viewpoint of forming a layer, it is preferably 1 to 30% by mass, more preferably 3 to 20% by mass, and even more preferably 5 to 15% by mass, based on the total amount of resin components in the first resin composition layer. .

(Content of component (F) in second resin composition layer)
When the second resin composition layer contains the (F) elastomer, the content of the (F) elastomer in the second resin composition layer is not particularly limited; From the viewpoint of forming a layer, preferably 0.5 to 20% by mass, more preferably 1 to 15% by mass, even more preferably 2 to 10% by mass, based on the total amount of resin components in the second resin composition layer. It is.

<(G) Organic peroxide>
It is preferable that the first resin composition layer and the second resin composition layer each further contain (G) an organic peroxide. (G) The organic peroxide is mainly a polymerization initiator for the thermal radical polymerization reaction of the ethylenically unsaturated group contained in the component (A) and, if necessary, the component (B).
When the first resin composition layer and the second resin composition layer contain (G) an organic peroxide, the formed interlayer insulating layer tends to further improve heat resistance, dielectric properties, etc. There is.
(G) Organic peroxides may be used alone or in combination of two or more.

(G) Organic peroxides include, for example, 1,1-di(t-butylperoxy)cyclohexane, 2,2-di(t-butylperoxy)butane, 2,2-di(4,4- Peroxyketals such as di-t-butylperoxycyclohexyl)propane and 1,1-di(t-amylperoxy)cyclohexane; Hydroperoxides such as cumene hydroperoxide and t-butyl hydroperoxide; - Alkyl peroxides such as butyl peroxyacetate and t-amyl peroxyisononanoate; t-butylcumyl peroxide, di-t-butyl peroxide, dicumyl peroxide, di-t-hexyl peroxide, 1 , 3-di(t-butylperoxyisopropyl)benzene and other dialkyl peroxides; t-butylperoxyacetate, t-butylperoxybenzoate, t-butylperoxyisopropyl monocarbonate and other peroxyesters; -Peroxycarbonates such as butylperoxyisopropyl carbonate and polyethertetrakis (t-butylperoxycarbonate); and diacyl peroxides such as dibenzoyl peroxide. Among these, 1,3-di(t-butylperoxyisopropyl)benzene is preferred.

(Content of component (G) in first resin composition layer)
When the first resin composition layer contains (G) an organic peroxide, the content of the (G) organic peroxide in the first resin composition layer is not particularly limited; From the viewpoint of forming an interlayer insulating layer with better adhesion, preferably 0.1 to 10 parts by mass, more preferably 1 to 7 parts by mass, per 100 parts by mass of component (A) in the first resin composition layer. Parts by weight, more preferably 1.5 to 4 parts by weight.

(Content of component (G) in second resin composition layer)
When the second resin composition layer contains (G) an organic peroxide, the content of the (G) organic peroxide in the second resin composition layer is not particularly limited; From the viewpoint of forming an interlayer insulating layer with better adhesion, preferably 0.1 to 10 parts by mass, more preferably 1 to 7 parts by mass, per 100 parts by mass of component (A) in the second resin composition layer. Parts by weight, more preferably 1.5 to 4 parts by weight.

<(H) Curing accelerator>
It is preferable that the first resin composition layer and the second resin composition layer each further contain (H) a curing accelerator.
When the first resin composition layer and the second resin composition layer contain the (H) curing accelerator, the formed interlayer insulating layer tends to further improve heat resistance, dielectric properties, etc. be.
(H) The curing accelerator may be used alone or in combination of two or more.

(H) As the curing accelerator, for example, 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 2-phenylimidazole, 2-phenyl-1-benzyl-1H-imidazole , 2-phenyl-4-methyl-5-hydroxymethylimidazole, isocyanate mask imidazole (addition reaction product of hexamethylene diisocyanate resin and 2-ethyl-4-methylimidazole); trimethylamine, N,N-dimethyl Tertiary substances such as octylamine, N-benzyldimethylamine, pyridine, N-methylmorpholine, hexa(N-methyl)melamine, 2,4,6-tris(dimethylaminophenol), tetramethylguanidine, m-aminophenol, etc. Amine; Organic phosphine such as tributylphosphine, triphenylphosphine, tris-2-cyanoethylphosphine; Phosphonium salt such as tri-n-butyl(2,5-dihydroxyphenyl)phosphonium bromide, hexadecyltributylphosphine chloride; Benzyltrimethylammonium Quaternary ammonium salts such as chloride and phenyltributylammonium chloride; polybasic acid anhydrides mentioned above; diphenyliodonium tetrafluoroborate, triphenylsulfonium hexafluoroantimonate, 2,4,6-triphenylthiopyrylium hexafluorophosphate Examples include.
Among these, imidazole compounds are preferred from the viewpoint of obtaining excellent curing action.

(Content of (H) component in first resin composition layer)
When the first resin composition layer contains (H) a curing accelerator, the content of the (H) curing accelerator in the first resin composition layer is not particularly limited, but the heat resistance and conductor adhesion are From the viewpoint of forming a more excellent interlayer insulating layer, preferably 0.1 to 10 parts by mass, more preferably 0.5 to 7 parts by mass, per 100 parts by mass of component (B) in the first resin composition layer. Parts by weight, more preferably 1 to 4 parts by weight.

(Content of (H) component in second resin composition layer)
When the second resin composition layer contains (H) a curing accelerator, the content of the (H) curing accelerator in the second resin composition layer is not particularly limited, but the heat resistance and conductor adhesion are From the viewpoint of forming a more excellent interlayer insulating layer, preferably 0.1 to 10 parts by mass, more preferably 0.5 to 7 parts by mass, per 100 parts by mass of component (B) in the second resin composition layer. Parts by weight, more preferably 1 to 4 parts by weight.

<(I) Other components>
The first resin composition layer and the second resin composition layer may contain components other than the above-mentioned components as (I) other components, if necessary.
(I) Other components include, for example, resins other than the above-mentioned components; organic fillers other than component (E); photosensitizers; polymerization inhibitors; foam stabilizers; pigments; adhesion aids such as melamine; Examples include foam stabilizers such as silicone compounds; thickeners; flame retardants.
Each of these may be used alone or in combination of two or more.
The content of the other components (I) in the first resin composition layer or the second resin composition layer may be adjusted as appropriate depending on each purpose, but for each, the content of the other component (I) in the resin containing the component In the composition layer, the amount may be 0.01 to 10% by weight, 0.05 to 5% by weight, or 0.1 to 1% by weight.

<Production method of photosensitive multilayer resin film>
The photosensitive multilayer resin film of this embodiment includes a resin composition (hereinafter also referred to as "resin composition (1)") for forming a first resin composition layer and a second resin composition layer. It can be manufactured using a resin composition (hereinafter also referred to as "resin composition (2)") for.
The first resin composition layer can be formed from the resin composition (1), and the suitable content of each component in the total solid content of the resin composition (1) is determined by The preferred content of each component is the same. Further, the second resin composition layer can be formed by the resin composition (2), and the preferable content of each component in the total solid content of the resin composition (2) is the second resin composition layer. The preferred content of each component in the layer is the same.
The resin composition (1) and the resin composition (2) can be manufactured by mixing the components to be added to each layer and the diluent used if necessary. For mixing each component, for example, a roll mill, a bead mill, a planetary mixer, a rotation-revolution mixer, etc. can be used.

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 bonding them together, both sides can be coated. The photosensitive multilayer resin film of this embodiment having a carrier film can be manufactured. In addition, as another method, one of the resin composition layers is formed on the carrier film, and the other resin composition is coated on the one resin composition layer. It can also be manufactured by the method of forming a resin composition layer.

Examples of the method for applying the resin composition (1) and the resin composition (2) include a method using a coating device such as a comma coater, a bar coater, a kiss coater, a roll coater, a gravure coater, and a die coater.
The drying temperature when drying the coating films of resin composition (1) and resin composition (2) is not particularly limited, but is preferably 60 to 150°C, more preferably 70 to 120°C, and even more preferably 80 to 120°C. The temperature is 100°C. Further, the drying time is not particularly limited, but is preferably 1 to 60 minutes, more preferably 2 to 30 minutes, and still more preferably 5 to 20 minutes.

Examples of the material of the carrier film include polyesters such as polyethylene terephthalate and polybutylene terephthalate; polyolefins such as polypropylene and polyethylene. The thickness of the carrier film is not particularly limited, but is preferably 5 to 100 μm, more preferably 10 to 60 μm, and even more preferably 15 to 45 μm.

[Printed wiring board and its manufacturing method]
The printed wiring board of this embodiment is a printed wiring board that has an interlayer insulating layer that is a cured product of the photosensitive multilayer resin film of this embodiment.
Note that the "interlayer insulating layer" included in the printed wiring board of the present embodiment includes, for example, a layer that has been subjected to various processing or treatments such as formation of vias and wiring, and roughening treatment.

The method for manufacturing the printed wiring board of this embodiment is not particularly limited as long as it is a method using the photosensitive multilayer resin film of this embodiment, but the method for manufacturing the printed wiring board including the following (1) to (4) is preferable.
(1): Laminating the photosensitive multilayer resin film of the present embodiment on one or both sides of the circuit board with the second resin composition layer serving as the attachment surface (hereinafter referred to as "lamination step (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): Curing the interlayer insulating layer having the vias by heating (hereinafter also referred to as "heat curing step (3)").
(4): Forming a circuit pattern on a 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 of this embodiment will be described with reference to FIG. 1 as appropriate.
In addition, in this specification, for convenience, a predetermined operation may be referred to as "XX process", but the "XX process" is not limited to only the aspects specifically described in this specification. .

(Lamination process (1))
In the laminating step (1), the photosensitive multilayer resin film of this embodiment is laminated on one or both sides of the circuit board, with the second resin composition layer serving as the attachment surface.
FIG. 1A shows a process of forming photosensitive layers 103 on both sides of a substrate 101 having a circuit pattern 102. In FIG.
The photosensitive layer 103 can be formed by laminating the photosensitive multilayer resin film of this embodiment on both sides of the substrate 101 so that the second resin composition layer becomes the attachment surface.
The laminate may be crimped using, for example, a vacuum laminator or the like while applying pressure and heating.
If a carrier film is attached to the photosensitive layer 103 after lamination, the carrier film may be peeled off before exposure, which will be described later, or after exposure.

(Via formation process (2))
In the via forming step (2), an interlayer insulating layer having vias is formed by exposing and developing the photosensitive layer formed in the laminating step (1).
FIG. 1B shows a step of forming an interlayer insulating layer 104 having vias 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 multilayer resin film is cured.

The exposure method for the photosensitive layer 103 may be, for example, a mask exposure method in which actinic rays are imagewise irradiated through a negative or positive mask pattern called artwork, an LDI (Laser Direct Imaging) exposure method, or a DLP exposure method. (Digital Light Processing) A method of irradiating actinic rays imagewise by a direct drawing exposure method such as an exposure method may be used.
Examples of active light sources include gas lasers such as carbon arc lamps, mercury vapor arc lamps, high-pressure mercury lamps, xenon lamps, and argon lasers; solid lasers such as YAG lasers; and semiconductor lasers that effectively emit ultraviolet or visible rays. For example, known light sources such as those that
The exposure amount may be adjusted as appropriate depending on the light source used, the thickness of the photosensitive layer, etc. For example, when exposing a photosensitive layer with a thickness of 1 to 100 μm using ultraviolet irradiation from a high-pressure mercury lamp, the exposure amount is not particularly limited, but is preferably 10 to 1,000 mJ/cm ² , more preferably 50 to 700 mJ/cm ² , more preferably 150 to 400 mJ/cm ² .

Next, if a carrier film is present on the photosensitive layer 103, development is performed after removing the carrier film. In 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 the method using wet development, a spray method is preferable from the viewpoint of improving resolution.
Examples of the developer include an alkaline aqueous solution, an aqueous developer, and an organic solvent developer, and among these, an alkaline aqueous solution is preferred.
After exposure and development, post-exposure may be performed from the viewpoint of increasing the degree of curing of the interlayer insulating layer. The exposure amount in post-exposure is not particularly limited, but is preferably 0.2 to 10 J/cm ² , more preferably 0.5 to 5 J/cm ² .

There is no particular restriction on the shape of the via, and in terms of cross-sectional shape, examples include a square, an inverted trapezoid, and the like. Note that an inverted trapezoid has a shape in which the upper side is longer than the lower side. Moreover, when explaining the shape in plan view, examples include a circle, a quadrangle, and the like.
By forming vias using the photolithography method of this embodiment, vias having an inverted trapezoidal cross-sectional shape can be formed. A via having this shape is preferable because the plated copper has a high ability to wrap around the via wall surface.
When the vias are formed by the photolithography method of this embodiment, the diameter of the vias can be made smaller than the diameter of the vias produced by laser processing. The diameter of the via formed by the manufacturing method of this embodiment may be, for example, 40 μm or less, 35 μm or less, or 30 μm or less. Although there is no particular restriction on the lower limit of the diameter of the via, it may be, for example, 15 μm or more, or 20 μm or more.

(Heat curing process (3))
In the heat curing step (3), the interlayer insulating layer having vias is heat hardened.
That is, in the heat curing step (3), the curing reaction of the thermosetting component contained in the photosensitive multilayer resin film of this embodiment is advanced by heating.
The heating temperature is not particularly limited, but is preferably 100 to 300°C, more preferably 120 to 200°C, and even more preferably 150 to 180°C. The heating time is not particularly limited, but is preferably 0.3 to 3 hours, more preferably 0.5 to 2 hours, and even more preferably 0.75 to 1.5 hours.

(Circuit pattern formation process (4))
In the interlayer insulating layer formed above, the layer formed by curing the first resin composition layer is exposed, so in the circuit pattern forming step (4), the first resin composition layer of the interlayer insulating layer is A circuit pattern is formed on the cured layer.
From the perspective of forming fine interconnections, circuit patterns can be 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 performed in this order. preferable.

The roughening process is a process of roughening the surface of the interlayer insulating layer to form uneven anchors. If smear occurs in the via forming step (2), roughening treatment and removal of the smear 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, a sodium fluoride/chromium/sulfuric acid roughening liquid, and the like.

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

FIG. 1D shows a step of forming a resist pattern 107 on the seed layer 106.
The resist pattern 107 can be formed, for example, by thermocompressing a dry film resist onto the seed layer 106 using a roll laminator or the like, exposing it to light, and developing it. Commercially available products can be used as the dry film resist.

The dry film resist may be exposed through a mask on which the desired wiring pattern is drawn. After exposure, the dry film resist is developed using an alkaline aqueous solution, and the unexposed portions are removed to form a resist pattern 107. Thereafter, plasma treatment may be performed to remove development residues from the dry film resist, if necessary.

FIG. 1(e) illustrates the process 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 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 electrolytic copper plating, the resist pattern 107 is removed using an alkaline aqueous solution or an amine stripping agent, and further, flash etching to remove the seed layer 106 between wirings, removal of the palladium catalyst, etc. are performed as appropriate by known methods. Furthermore, if necessary, a post-baking treatment may be performed to sufficiently heat-cure unreacted thermosetting components.

FIG. 1(f) shows a multilayer printed wiring board 100A that is 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 multilayer resin film for solder resist.

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, For example, it is also suitable for forming a cavity for housing a chip or a passive element. For example, in the above description of the printed wiring board, the cavity can be suitably formed by making the pattern drawn when forming the pattern by exposing the photosensitive multilayer resin film to a pattern that can form the desired cavity. I can do it.

[Semiconductor package]
The semiconductor package of this embodiment is a semiconductor package that includes the printed wiring board of this embodiment.
The semiconductor package of this embodiment can be manufactured by, for example, mounting a semiconductor element such as a semiconductor chip or a memory in a predetermined position on the printed wiring board of this embodiment, and sealing the semiconductor element with a sealing resin or the like. I can do it.

Hereinafter, the present embodiment will be described in more detail with reference to examples, but the present embodiment is not limited to these examples.

[Method of measuring acid value]
The acid value was calculated from the amount of potassium hydroxide aqueous solution required to neutralize the measurement target.

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

[Measurement method of silicon atom concentration]
The carrier film-attached photosensitive multilayer resin film produced in each example was irradiated with ultraviolet rays at a light intensity of 400 mJ/cm ² (wavelength 365 nm) using a flat exposure machine while having carrier films on both sides. Thereafter, the carrier films on both sides were peeled off and irradiated with ultraviolet light at a light intensity of 2 J/cm ² (wavelength 365 nm) using a UV conveyor exposure machine. Next, the mixture was heated at 170° C. for 1 hour using a hot air circulation dryer to obtain a cured photosensitive multilayer resin film. The obtained cured photosensitive multilayer resin film is embedded and cured with embedding resin, and then polished using a polisher (manufactured by Refinetech Co., Ltd., trade name "Refine Polisher") to form a photosensitive multilayer resin film. A cross section of the cured product was cut out and used as a test piece.
Next, a scanning electron microscope (SEM) (manufactured by Hitachi High-Tech Corporation, product name "SU-5000") equipped with an energy dispersive X-ray spectroscopy (EDX) as an elemental analysis device The cross section of the cured product of the photosensitive multilayer resin film was observed at a magnification of 3,000 times. Note that FIG. 2 shows an example of a cross-sectional image 10 of a cured product of a photosensitive multilayer resin film. The cured product includes layer 1 (hereinafter also referred to as "first layer 1") obtained by curing the first resin composition layer and layer 2 (hereinafter referred to as "layer 1") obtained by curing the second resin composition layer. 2). Hereinafter, the measurement position of silicon atom concentration will be explained with reference to FIG. 2.
In the cross-sectional image 10 shown in FIG. 2, a line corresponding to the surface of the first layer 1 opposite to the surface facing the second layer 2 was identified as the reference line BL1 of the first layer. Further, the surface of the second layer 2 opposite to the surface facing the first layer 1 was specified as the reference line BL2 of the second layer.
In addition, if there are irregularities on the surfaces of the first layer and second layer that specify the reference line BL1 or reference line BL2, the surface positions of each layer are measured at least 10 points at equal intervals in the entire range of the cross-sectional image. A straight line obtained by plotting and approximating this using the least squares method can be used as the reference line BL1 or the reference line BL2.
On the measurement line L1 parallel to the reference line BL1, which is 1 μm apart from the reference line BL1 toward the second layer 2 side, the elemental analysis of the first layer 1 is performed using the above elemental analyzer, and the calculated average The silicon atom concentration was defined as the "silicon atom concentration of the first layer." In addition, elemental analysis of the second layer 2 was performed using the above elemental analyzer on the measurement line L2 parallel to the reference line BL2, which is 1 μm apart from the reference line BL2 toward the first layer 1 side, and the calculated values were The average silicon atom concentration obtained was defined as the "silicon atom concentration of the second layer." The length of each line for elemental analysis was 40 μm.
The ratio of the silicon atom concentration of the first layer to the silicon atom concentration of the second layer obtained above was calculated as the silicon atom concentration ratio [(first layer)/(second layer)].

[Manufacture of photosensitive multilayer resin film]
Examples 1 to 9, Comparative Examples 1 to 8
Each component is blended according to the composition shown in Table 1 (the units of numerical values in the table are parts by mass, and in the case of solutions, it is the solid content equivalent amount), and kneaded using a three-roll mill and a rotation-revolution mixer. did. Thereafter, methyl ethyl ketone was added so that the solid content concentration was 65% by mass, resulting in a resin composition (1) for forming the first resin composition layer and a resin for forming the second resin composition layer. Compositions (2) were obtained.
Next, the resin composition (1) was applied onto a carrier film (PET film, manufactured by Teijin Ltd., product name "G2-16", thickness 16 μm), and dried at 100°C using a hot air convection dryer. was dried for 10 minutes to form a first resin composition layer with a carrier film (the thickness of the first resin composition layer was 5 μm).
In addition, the resin composition (2) was applied onto a carrier film different from the above (PET film manufactured by Teijin Ltd., product name "G2-16", thickness 16 μm), and a hot air convection dryer was used to coat the resin composition (2). Then, it was dried at 100° C. for 10 minutes to form a second resin composition layer with a carrier film (the thickness of the second resin composition layer was 20 μm).
By bonding together 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, the carrier film, the first resin composition layer A photosensitive multilayer resin film with a carrier film (thickness of the photosensitive multilayer resin film: 25 μm) was obtained, which had a second resin composition layer and a carrier film in this order.

The following evaluations were performed using the produced photosensitive multilayer resin film. The results are shown in Table 1.

[Measurement of relative permittivity (Dk) and dielectric loss tangent (Df)]
Two photosensitive multilayer resin films with a carrier film produced in each example were prepared by peeling and removing the carrier film on the second resin composition layer side, and the second resin composition layers were bonded together.
Next, with the carrier films on both sides still in place, ultraviolet rays were irradiated with a light intensity of 400 mJ/cm ² (wavelength 365 nm) using a flat exposure machine. Next, the carrier films on both sides were peeled off and irradiated with ultraviolet light at a light intensity of 2 J/cm ² (wavelength 365 nm) using a UV conveyor exposure machine. Thereafter, it was heated at 170° C. for 1 hour using a hot air circulation dryer and cut into a size of 7 cm×10 cm, which was used as a measurement sample for dielectric constant (Dk) and 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 constant was measured in the 10 GHz band using the split post dielectric resonator method (SPDR method). (Dk) and dielectric loss tangent (Df) were measured and evaluated based on the following criteria.
(Evaluation criteria for relative dielectric constant (Dk))
A: 2.8 or less B: More than 2.8 to 3.0 or less C: More than 3.0 (Evaluation criteria for dielectric loss tangent (Df))
A: 0.0100 or less B: More than 0.0100 to 0.0120 or less C: More than 0.0120

[Evaluation of via resolution]
(1) Preparation of laminate for evaluation Copper of printed wiring board substrate (manufactured by Showa Denko Materials Co., Ltd., product name "MCL-E-679") in which copper foil (thickness 12 μm) is laminated on a glass epoxy base material. The surface of the foil was subjected to a roughening pretreatment using a roughening pretreatment liquid (manufactured by MEC Co., Ltd., trade name "CZ-8100"), and then washed with water and dried. Next, the carrier film on the second resin composition layer side of the carrier film-attached photosensitive multilayer resin film produced in each example was peeled off and removed so that the exposed second resin composition layer became the attachment surface. , and was laminated onto the copper foil of the printed wiring board substrate which had been subjected to the above-mentioned roughening pretreatment. For lamination, a press-type vacuum laminator (manufactured by Meiki Seisakusho Co., Ltd., product name "MVLP-500") was used, and the lamination conditions were: press hot plate temperature 70 ° C, vacuum drawing time 20 seconds, lamination press time The pressure was set to 30 seconds, the pressure was 4 kPa or less, and the pressure was 0.4 MPa. After the lamination treatment, the laminate was left at room temperature for 1 hour or more 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 printed wiring board substrate.
(2) Sensitivity measurement A 41 step tablet was placed on the carrier film on the first resin composition layer side of the evaluation laminate obtained above. Next, exposure was performed using a direct imaging exposure device (manufactured by Oak Seisakusho Co., Ltd., trade 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 a diameter of 30 to 100 μm were arranged in a grid pattern.
After exposure, after being left at room temperature for 30 minutes, the carrier film on the first resin composition layer side of the evaluation laminate obtained above was removed, and a 1% by mass sodium carbonate aqueous solution at 30°C was used to remove the unexposed film. The photosensitive multilayer resin film was spray developed for 60 seconds. After development, the exposure energy amount at which the remaining gloss step number of the 41 step tablet was 4.0 was defined as the sensitivity (unit: mJ/cm ² ) of the photosensitive multilayer resin film. Using a pattern exposed at this sensitivity, evaluation was made according to the following evaluation criteria.
(3) Evaluation of resolution of vias The resolution of vias is determined by exposing and spray developing a via pattern with an exposure energy amount that is the sensitivity of the photosensitive multilayer resin film determined in (2) above. It was observed using an optical microscope and evaluated according to the following criteria.
(Evaluation criteria)
A: The φ60 μm via portion of the dot pattern is open.
C: The φ60 μm via portion of the dot pattern was not opened.

[Evaluation of adhesive strength with plated copper]
(1) Preparation of evaluation laminate and sensitivity measurement of photosensitive multilayer resin film In steps (1) and (2) of the above [Evaluation of via resolution], the exposure machine used was an ultra-high pressure mercury lamp. The steps in (1) and (2) of [Evaluation of via resolution] above were followed except that the light source was changed to a parallel light exposure machine (manufactured by Oak Seisakusho Co., Ltd., product name "EXM-1201"). In the same manner as above, prepare a laminate for evaluation, determine the amount of exposure energy that gives a gloss remaining step number of 8.0, and calculate this as the sensitivity (unit: mJ/cm ² ) of the photosensitive multilayer resin film. did.
(2) Exposure step and development step The carrier film on the first resin composition layer side of the laminate for evaluation was peeled off, and the entire surface was exposed to light with an exposure energy amount corresponding to the sensitivity determined above, and the photosensitive multilayer resin film was hardened. After exposure, the photosensitive multilayer resin film was left to stand at room temperature for 30 minutes, and then the unexposed areas of the photosensitive multilayer resin film were spray developed for 60 seconds using a 1% by mass aqueous sodium carbonate solution at 30°C.
(3) Post-cure treatment Subsequently, post-UV cure was performed using a high-pressure mercury lamp irradiation type UV conveyor device (manufactured by Oak Seisakusho Co., Ltd.) at a conveyor speed such that the exposure amount was 2 J/cm ² . Thereafter, it was heated at 170° C. for 1 hour using a hot air circulation dryer.
(4) Roughening treatment The above-mentioned heated evaluation laminate was treated at 70°C for 5 minutes using the swelling liquid “Swelling Dip Securigant P”, and then treated with the roughening liquid “Dosing Securigant P500J”. A roughening treatment was performed at 70° C. for 10 minutes. Subsequently, neutralization treatment was performed at 50° C. for 5 minutes using a neutralizing solution “Reduction Conditioner Securigant P500”. Thereafter, 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 treatment The evaluation laminate after the above roughening treatment was subjected to electroless plating treatment at 30°C for 15 minutes using electroless plating solution "Prigant MSK-DK" (manufactured by Atotech Japan Co., Ltd.). I did it. Next, electroplating was performed at 24° C. and 2 A/dm ² for 1.5 hours using an electroplating solution "Kaparaside HL" (manufactured by Atotech Japan Co., Ltd.) to form plated copper on the interlayer insulating layer. Note that the thickness of the plated copper was 25 μm.
(6) Measurement of adhesive strength with plated copper The adhesive strength with plated copper was evaluated by measuring vertical peel strength at 23° C. in accordance with JIS C6481:1996 and according to the following criteria.
(Evaluation criteria)
A: More than 0.4kN/m B: More than 0.1kN/m to 0.4kN/m or less C: 0.1kN/m or less

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

[(A) Component]
-Compound having a carboxyl group and an acryloyl group: manufactured by Nippon Kayaku Co., Ltd., trade name "ZXR-1807H", acid value: 110 mgKOH/g, weight average molecular weight (Mw): 2,000

[(B) Component]
- Biphenylaralkyl epoxy resin: manufactured by Nippon Kayaku Co., Ltd., trade name "NC-3000-L", epoxy group equivalent: 272 g/eq
- Naphthol type epoxy resin: manufactured by Nippon Steel & Sumitomo Metal Corporation, product name "ESN-475V", epoxy group equivalent: 325 g/eq
・Maleimide resin: Aromatic bismaleimide resin with an indane skeleton

[(C) Component]
・Photoinitiator 1: phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide ・Photoinitiator 2: 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3- yl]ethanone 1-(O-acetyloxime)

[(D) Component]
・Silica 1: Manufactured by Admatex Co., Ltd., product name “SC2050-MB”, average particle diameter (D ₅₀ ): 0.5 μm, true density 2,200 kg/m ³
・Silica 2: Manufactured by TAT, trade name “BQQ-0710SCB”, average particle diameter (D ₅₀ ): 0.7 μm, true density 1,350 kg/m ³

[(E) component]
・Polytetrafluoroethylene particles: manufactured by Mitsubishi Pencil Co., Ltd., trade name “MPT-N8”, average particle diameter (D ₅₀ ): 0.2 to 0.3 μm

[(F) component]
・Polybutadiene-based elastomer: Butadiene-styrene-random copolymer, manufactured by Cray Valley, trade name "Ricon100", number average molecular weight (Mn): 4,500
- Acid anhydride-modified polybutadiene: manufactured by Cray Valley, trade name "Ricon131MA17", number average molecular weight (Mn): 5,400, number of acid anhydride groups in one molecule: 9

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

[(H) component]
・Curing accelerator: 1-benzyl-2-phenylimidazole

[(I) Component]
・Sensitizer: 4,4'-bis-(diethylamino)benzophenone ・Polymerization inhibitor: 4-tert-butylpyrocatechol

From Table 1, the cured products formed from the photosensitive multilayer resin films of Examples 1 to 9 of the present embodiment all had excellent dielectric properties and high conductor adhesion.

1 First layer 2 Second layer BL1 First layer reference line BL2 Second layer reference line L1 First layer measurement line L2 Second layer measurement line 10 Cross-sectional image 100A Multilayer printed wiring board 101 Board 102 Circuit pattern 103 Photosensitive layer 104 Interlayer insulating layer 105 Via 106 Seed layer 107 Resist pattern 108 Copper circuit layer 109 Solder resist layer

Claims

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, (C) a photopolymerization initiator, and (D) an inorganic filler;
The first resin composition layer contains silica as the (D) inorganic filler,
The second resin composition layer further contains (E) a fluorine-containing resin,
A photosensitive multilayer resin film, wherein the silicon atom concentration in the first resin composition layer is higher than the silicon atom concentration in the second resin composition layer.
The first resin composition layer and the second resin composition layer each contain a compound having an ethylenically unsaturated group and an acidic substituent as the (A) compound having an ethylenically unsaturated group. , The photosensitive multilayer resin film according to claim 1.
In the first resin composition layer and the second resin composition layer, the thermosetting resin (B) is each selected from the group consisting of epoxy resin, maleimide resin, allyl resin, and vinyl resin. The photosensitive multilayer resin film according to claim 1, containing at least one species.
The first resin composition layer and the second resin composition layer each contain an epoxy resin as the (B) thermosetting resin, and each contains an epoxy resin based on the mass in the first resin composition layer. The photosensitive multilayer resin film according to claim 3, wherein the content of the epoxy resin is greater than the content of the epoxy resin on a mass basis in the second resin composition layer.
The photosensitive multilayer resin film according to claim 1, wherein the content of silica in the first resin composition layer is 5 to 70% by mass.
The photosensitive multilayer resin film according to claim 1, wherein the second resin composition layer contains silica having a true density of 1,500 kg/m 3 or less as (D) an inorganic filler.
According to claim 1, the content of the fluorine-containing resin (E) in the second resin composition layer is 10 to 70% by mass based on the total amount of resin components in the second resin composition layer. photosensitive multilayer resin film.
The photosensitive multilayer resin film according to claim 1, wherein the first resin composition layer and the second resin composition layer each further contain (F) an elastomer.
The photosensitive multilayer resin film according to claim 1, wherein the content of the inorganic filler (D) in the second resin composition layer is less than 60% by mass.
The ratio of the silicon atom concentration in the first resin composition layer to the silicon atom concentration in the second resin composition layer [(first layer)/(second layer)] is 1.1 to 15. The photosensitive multilayer resin film according to claim 1.
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 formed by curing the photosensitive multilayer resin film. The photosensitive multilayer resin film according to claim 1, which is a layer having a surface to be pasted.
The photosensitive multilayer resin film according to claim 1, which is used for forming an interlayer insulating layer having photovias.
A printed wiring board having an interlayer insulating layer that is a cured product of the photosensitive multilayer resin film according to claim 1.
A semiconductor package comprising the printed wiring board according to claim 13.
A method for manufacturing a printed wiring board, including the following (1) to (4).
(1): Laminating the photosensitive multilayer resin film according to any one of claims 1 to 12 on one or both sides of a circuit board, with the second resin composition layer serving as a pasting surface. .
(2): Forming an interlayer insulating layer having vias by exposing and developing the photosensitive multilayer resin film laminated in (1) above.
(3): Curing the interlayer insulating layer having the via by heating.
(4): Forming a circuit pattern on a layer formed by curing the first resin composition layer of the interlayer insulating layer.