CN117859095A

CN117859095A - Photosensitive resin composition, photosensitive resin film, multilayer printed wiring board, semiconductor package, and method for producing multilayer printed wiring board

Info

Publication number: CN117859095A
Application number: CN202180101780.7A
Authority: CN
Inventors: 今野忧子; 片木秀行; 阿部宏平; 雪冈谅; 中村英博
Original assignee: Lishennoco Co ltd
Current assignee: Lishennoco Co ltd
Priority date: 2021-08-30
Filing date: 2021-08-30
Publication date: 2024-04-09
Also published as: WO2023031986A1

Abstract

The present invention provides a composition comprising (X) a true density of less than or equal to 1,500kg/m ³ A photosensitive resin composition of an inorganic filler. Further, a photosensitive resin film formed using the photosensitive resin composition is provided. Also provided is a multilayer printed wiring board comprising an interlayer insulating layer formed using the photosensitive resin composition or the photosensitive resin film, and a method for producing the multilayer printed wiring board. And further provides a semiconductor package comprising the multilayer printed wiring board and a semiconductor element.

Description

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

Technical Field

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

Background

In recent years, miniaturization and higher performance of electronic devices have been advanced, and multilayer printed wiring boards have been increased in density by increasing the number of circuit layers, miniaturization of wiring, and the like. In particular, the semiconductor package substrate such as BGA (ball grid array) and CSP (chip size package) on which a semiconductor chip is mounted has been remarkably increased in density, and in addition to the miniaturization of wiring, the thinning of an insulating layer and the further reduction in diameter of a via hole (also referred to as a via hole) for interlayer connection have been required.

As a conventionally employed method for manufacturing a printed wiring board, there is a method for manufacturing a multilayer printed wiring board using a build-up system (for example, refer to patent document 1) in which an interlayer insulating layer and a conductor circuit layer are laminated in this order. In multilayer printed wiring boards, a semi-additive method of forming a circuit by plating is the mainstream with miniaturization of the circuit.

In the conventional semi-additive method, for example, (1) a thermosetting resin film is laminated on a conductor circuit, and then the thermosetting resin film is cured by heating to form an "interlayer insulating layer". (2) Then, after forming a via hole for interlayer connection by laser processing, desmear treatment and roughening treatment are performed by alkali permanganate treatment or the like. (3) Then, after electroless copper plating treatment is performed on the substrate, patterning is performed using a resist, and copper plating is performed to form a copper circuit layer. (4) Then, the resist was peeled off, and then, the electroless layer was flash etched, thereby forming a copper circuit.

As described above, laser processing is the main stream as a method of forming a through hole in an interlayer insulating layer formed by curing a thermosetting resin film, but the reduction in diameter of a through hole by laser irradiation using a laser processing machine is reaching a limit. Further, in the formation of the through holes by using a laser processing machine, it is necessary to form the respective through holes one by one, and when a plurality of through holes are required to be provided due to the high density, the formation of the through holes takes a lot of time, which is a problem in that the manufacturing efficiency is poor.

Under such circumstances, as a method capable of forming a plurality of through holes at once, a method has been proposed in which a plurality of small-diameter through holes are formed at once by photolithography using a photosensitive resin composition containing an acid-modified vinyl-containing epoxy resin, a photopolymerizable compound, a photopolymerization initiator, an inorganic filler, and a silane compound, and the content of the inorganic filler being 10 to 80 mass% (for example, refer to patent document 2).

Patent document 2 discloses one of problems of suppressing the decrease in adhesion to copper plating caused by using a photosensitive resin composition instead of a conventional thermosetting resin composition as a material for an interlayer insulating layer or a surface protective layer, and further discloses problems of resolution of a via hole and adhesion to a substrate and a chip member of a silicon material, and solves these problems.

In recent years, a substrate material is required to be suitable for a fifth-generation mobile communication system (5G) antenna using high-frequency band electric waves and a millimeter wave radar using higher-frequency band electric waves. Therefore, as one of the targets, there is a need to develop a resin composition which further improves the relative dielectric constant at the "10GHz band". However, in the technique of patent document 2, there is room for improvement in the relative dielectric constant in the 10GHz band.

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open No. 7-304931

Patent document 2: japanese patent laid-open publication No. 2017-116652

Disclosure of Invention

Problems to be solved by the invention

In order to reduce the relative permittivity in the 10GHz band, the present inventors have studied that polytetrafluoroethylene (hereinafter referred to as ptfe) particles having a very low relative permittivity are contained in a photosensitive resin composition. However, it was found that: although the relative permittivity can be certainly reduced when only PTFE is contained in the photosensitive resin composition, there is a problem that the adhesion strength to copper plating is reduced, and it is difficult to achieve both the relative permittivity in the 10GHz band and the adhesion strength to copper plating.

Accordingly, an object of the present disclosure is to provide a photosensitive resin composition exhibiting excellent relative permittivity and high adhesion strength with copper plating at 10GHz band, and a photosensitive resin film formed using the photosensitive resin composition, and to provide a multilayer printed wiring board, a method for manufacturing the same, and a semiconductor package.

Means for solving the problems

The present inventors have conducted intensive studies and as a result, have found that the above object can be achieved by the present disclosure.

The present disclosure includes the following embodiments [1] to [18].

[1]A photosensitive resin composition comprising (X) a true density of 1,500kg/m or less ³ Is a filler material for a ceramic material.

[2] The photosensitive resin composition according to [1], wherein the volume average particle diameter of the component (X) is 0.3 to 3. Mu.m.

[3] The photosensitive resin composition according to the item [1] or [2], wherein the content of the component (X) is 1 to 45% by volume based on the total solid content of the photosensitive resin composition.

[4] The photosensitive resin composition according to any one of [1] to [3], further comprising (A) a photopolymerizable compound having an ethylenically unsaturated group and an acidic substituent, and (B) a thermosetting resin.

[5] The photosensitive resin composition according to the item [4], wherein the component (A) comprises an alicyclic skeleton represented by the following general formula (A-1).

[ chemical 1]

(wherein R is ^A1 An alkyl group having 1 to 12 carbon atoms may be substituted at any position in the alicyclic skeleton. m is m ¹ Is an integer of 0 to 6. Is a junction with other structures. )

[6] The photosensitive resin composition according to [4] or [5], wherein the equivalent ratio of the acidic substituent of the component (A) to the epoxy group of the component (B) [ epoxy group/acidic substituent ] is 0.5 to 6.0.

[7] The photosensitive resin composition according to any one of [1] to [6], further comprising (C) a crosslinking agent.

[8] The photosensitive resin composition according to any one of [1] to [7], further comprising (D) an elastomer.

[9] The photosensitive resin composition according to any one of [1] to [8], further comprising (E) an organic filler.

[10] The photosensitive resin composition according to the above [9], wherein the component (E) contains resin particles formed of at least one selected from the group consisting of resins having fluorine atoms, polyethylene, polypropylene, polystyrene, polyphenylene ether and silicone.

[11] The photosensitive resin composition according to the above [9] or [10], wherein the content of the component (E) is 1 to 45% by volume based on the total solid content of the photosensitive resin composition.

[12] The photosensitive resin composition according to any one of [1] to [11], further comprising (H) a photopolymerization initiator.

[13] The photosensitive resin composition according to [12], which comprises two or more of the above (H) components.

[14] A photosensitive resin composition for forming an optical via, comprising the photosensitive resin composition of any one of [1] to [13 ].

[15] A photosensitive resin film formed using the photosensitive resin composition according to any one of the above [1] to [13 ].

[16] A multilayer printed wiring board comprising an interlayer insulating layer formed using the photosensitive resin composition according to any one of [1] to [13] or the photosensitive resin film according to [15 ].

[17] A semiconductor package comprising the multilayer printed wiring board according to [16] above and a semiconductor element.

[18] A method for manufacturing a multilayer printed wiring board, comprising the following steps (1) to (4).

(1): the photosensitive resin film of [15] above is laminated on one or both sides of a circuit board.

(2): the photosensitive resin film laminated in the above (1) is exposed to light and developed, thereby forming an interlayer insulating layer having a through hole.

(3): and roughening the through hole and the interlayer insulating layer.

(4): a circuit pattern is formed on the interlayer insulating layer.

Effects of the invention

According to the present disclosure, a photosensitive resin composition exhibiting excellent relative permittivity in the 10GHz band and high adhesion strength with copper plating can be provided. Further, a photosensitive resin film formed using the photosensitive resin composition can be provided. Further, a multilayer printed wiring board including an interlayer insulating layer formed using the photosensitive resin composition or the photosensitive resin film, and a method for manufacturing the multilayer printed wiring board can be provided. And further can provide a semiconductor package comprising the multilayer printed wiring board and a semiconductor element.

Drawings

Fig. 1 is a schematic view showing one embodiment of a process for producing a multilayer printed wiring board using the photosensitive resin film of the present embodiment as a material of at least one of a surface protective layer and an interlayer insulating layer.

Detailed Description

In the numerical ranges described in the present specification, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples. In addition, the lower limit value and the upper limit value of the numerical range may be arbitrarily combined with the lower limit value or the upper limit value of the other numerical range, respectively. In the expression "AA to BB" of the numerical range, the numerical values AA and BB at both ends are included as a lower limit value and an upper limit value, respectively.

In the present specification, for example, the expression "10 or more" means a numerical value of 10 and more than 10, and the numerical values are also different. For example, the expression "10 or less" means a numerical value of 10 or less, and the numerical values are different from each other.

In the present specification, when a plurality of substances corresponding to the respective components are present, unless otherwise specified, the content of the respective components in the photosensitive resin composition means the total content of the plurality of substances present in the photosensitive resin composition.

In the present specification, the "number of ring-forming carbon atoms" is the number of carbon atoms required for forming a ring, and does not include the number of carbon atoms of a substituent of the ring. For example, the number of ring-forming carbon atoms of both the cyclohexane skeleton and the methylcyclohexane skeleton is 6.

The expression "(meth) acrylic acid XX" means one or both of acrylic acid XX and methacrylic acid XX corresponding thereto. In addition, "(meth) acryl" means one or both of acryl and methacryl.

In the present specification, unless otherwise specified, "relative permittivity" refers to a relative permittivity in the 10GHz band.

Further, the present embodiment also includes any combination of the items described in the present specification.

[ photosensitive resin composition ]

The photosensitive resin composition according to one embodiment of the present disclosure (hereinafter, may be simply referred to as the present embodiment) contains (X) a true density of 1,500kg/m or less ³ Is sensitive to the inorganic fillerA light-emitting resin composition.

In this specification, the above component may be simply referred to as an "(X) component", and the other components may be similarly referred to as "components".

In the present specification, the "resin component" is the component (a) and the component (B) described later, and includes other components (for example, the components (C), (D), (E), (F), (G), (H), and (I)) that may be contained as needed, but does not include the component (X), other inorganic filler, pigment, and other inorganic compound. The term "solid component" is a non-volatile component excluding volatile substances such as water and solvents contained in the photosensitive resin composition, and means a component that does not volatilize and remains when the resin composition is dried, and also includes a component that is liquid, syrup-like, and wax-like at room temperature in the vicinity of 25 ℃.

The photosensitive resin composition of the present embodiment is excellent in relative permittivity in the 10GHz band and is suitable for via formation by photolithography (also referred to as optical via formation), and therefore is suitable for forming one or more selected from the group consisting of optical via and interlayer insulating layer. Here, in the present disclosure, for example, when the expression of "layer" is made as an interlayer insulating layer or the like, a mode in which at least a part of the layer is formed in an island shape, a mode in which the layer is not entirely formed, a mode in which the layer is perforated, a case in which an interface with an adjacent layer is not clear, or the like is included in the "layer".

The photosensitive resin composition of the present embodiment is suitable for a negative photosensitive resin composition.

The following describes the component (X), and then the other components that can be contained in the photosensitive resin composition according to the present embodiment.

The true density of < (X) is less than or equal to 1,500kg/m ³ Inorganic filler material of >)

The photosensitive resin composition of the present embodiment has a true density of 1,500kg/m or less ³ As the (X) component, exhibits excellent relative permittivity in the 10GHz band and high adhesion strength with copper plating. Here, theThe true density of the component (X) is a value measured by a dry automatic densitometer "AccuPycII 1340" (manufactured by Shimadzu corporation), more specifically, a value measured according to the method described in examples.

Although the exact mechanism showing excellent relative permittivity and high adhesion strength to copper plating is not clear, it is speculated that: by a true density of less than or equal to 1,500kg/m ³ So that the space at the molecular level of the inorganic filler material becomes large, which may lead to a decrease in the relative dielectric constant. Further, it is considered that since the component (X) is an inorganic filler, the adhesion strength to copper plating such as PTFE does not significantly decrease, and therefore both a decrease in the relative dielectric constant and a high adhesion strength to copper plating can be achieved. However, the range of the photosensitive resin composition according to the present embodiment is not limited by this assumption.

The true density of the component (X) is preferably 1,000 to 1,500kg/m from the viewpoints of the relative dielectric constant and the adhesion strength to copper plating ³ More preferably 1,100 to 1,500kg/m ³ More preferably 1,200 to 1,500kg/m ³ Particularly preferably 1,250 to 1,450kg/m ³ Most preferably 1,250 to 1,400kg/m ³ 。

The component (X) may be solid particles, or hollow particles, and is preferably solid particles.

As the component (X), silica (SiO) ₂ ) Alumina (Al) ₂ O ₃ ) Titanium oxide (TiO) ₂ ) Tantalum oxide (Ta) ₂ O ₅ ) Zirconium oxide (ZrO) ₂ ) Silicon nitride (Si) ₃ N ₄ ) Barium titanate (BaO. TiO) ₂ ) Barium carbonate (BaCO) ₃ ) Magnesium carbonate (MgCO) ₃ ) Aluminum hydroxide (Al (OH) ₃ ) Magnesium hydroxide (Mg (OH) ₂ ) Lead titanate (PbO. TiO) ₂ ) Lead zirconate titanate (PZT), lead lanthanum zirconate titanate (PLZT), gallium oxide (Ga) ₂ O ₃ ) Spinel (MgO. Al) ₂ O ₃ ) Mullite (3 Al) ₂ O ₃ ·2SiO ₂ ) Cordierite (2MgO.2Al) ₂ O ₃ /5SiO ₂ ) Talc (3MgO.4SiO) ₂ ·H ₂ O), aluminum Titanate (TiO) ₂ ·Al ₂ O ₃ ) Yttria-containing zirconia (Y) ₂ O ₃ ·ZrO ₂ ) Barium silicate (BaO.8SiO) ₂ ) Boron Nitride (BN), calcium carbonate (CaCO) ₃ ) Barium sulfate (BaSO) ₄ ) Calcium sulfate (CaSO) ₄ ) Zinc oxide (ZnO), magnesium titanate (MgO. TiO) ₂ ) Hydrotalcite, mica, calcined kaolin, carbon (C), and the like. Among them, silica is preferable from the viewpoints of heat resistance, low thermal expansion and relative permittivity.

As the component (X), commercially available ones can be used. As true density less than or equal to 1,500kg/m ³ Examples of the silica include "BQQ-0710SCB" (manufactured by TAT) and "BQQ-0310SCB" (manufactured by TAT). The true density is less than or equal to 1,500kg/m ³ The silica of (2) is not particularly limited, and preferably has Si-R in addition to Si-O-bond ^X Bond (R) ^X Represents an organic group. ).

The component (X) may be a component surface-treated with a coupling agent such as a silane coupling agent or a component surface-treated with no coupling agent from the viewpoint of improving dispersibility in the photosensitive resin composition. Examples of the silane coupling agent include an aminosilane coupling agent, an epoxy silane coupling agent, a phenylsilane coupling agent, an alkylsilane coupling agent, an alkenylsilane coupling agent, an alkynylsilane coupling agent, a haloalkylsilane coupling agent, a siloxane coupling agent, a hydrosilane coupling agent, a silazane coupling agent, an alkoxysilane coupling agent, a chlorosilane coupling agent, a (meth) acrylic silane coupling agent, an isocyanurate silane coupling agent, a ureido silane coupling agent, a mercapto silane coupling agent, a sulfide silane coupling agent, and an isocyanate silane coupling agent.

The volume average particle diameter of the component (X) is preferably 0.3 to 3. Mu.m, more preferably 0.3 to 2.5. Mu.m, still more preferably 0.3 to 2.0. Mu.m, particularly preferably 0.3 to 1.7. Mu.m, and may be 0.3 to 1.2. Mu.m, or may be 1.2 to 2.0. Mu.m. If the volume average particle diameter of the component (X) is equal to or larger than the lower limit, the low thermal expansion tends to be excellent, and if it is equal to or smaller than the upper limit, the resolution of the through holes tends to be excellent. If the volume average particle diameter of the component (X) is 2.5 μm or less, the resolution of the via hole tends to be very good.

From the viewpoint of improving the adhesion to copper plating and resolution of the through hole, the component (X) may be two or more kinds of inorganic filler having different volume average particle diameters.

The volume average particle diameter was determined by measuring particles dispersed in a solvent at a refractive index of 1.38 using a submicron particle analyzer (trade name: N5, manufactured by Beckmann Kort Co., ltd.) according to International Standard Specification ISO13321, and obtaining the particles as a particle diameter corresponding to 50% of the cumulative value in the particle size distribution (volume basis).

In the photosensitive resin composition of the present embodiment, the content of the component (X) is not particularly limited, but is preferably 1 to 45% by volume, more preferably 3 to 40% by volume, still more preferably 5 to 40% by volume, and may be 5 to 25% by volume, or may be 25 to 40% by volume, based on the total solid content of the photosensitive resin composition. If the content of the (E) inorganic filler is greater than or equal to the above-mentioned lower limit value, there is a tendency to obtain a lower relative dielectric constant and thermal expansion coefficient, and if it is less than or equal to the above-mentioned upper limit value, there is a tendency to obtain more excellent adhesion strength with copper plating and resolution of the through-hole.

The photosensitive resin composition of the present embodiment preferably further contains (a) a photopolymerizable compound having an ethylenic unsaturated group and an acidic substituent, and (B) a thermosetting resin. The following will describe the components (A) and (B) in order, and then the other components will also describe them.

Photopolymerizable compound having ethylenic unsaturated group and acidic substituent

(A) The component (A) is a photopolymerizable compound having an ethylenically unsaturated group and an acidic substituent.

(A) The components may be used singly or in combination of two or more.

(A) The component (a) is a compound exhibiting photopolymerization, particularly radical polymerization, because it has an ethylenically unsaturated group.

Examples of the ethylenically unsaturated group contained in the component (a) include a functional group exhibiting photopolymerization such as a vinyl group, an allyl group, an propynyl group, a butenyl group, an ethynyl group, a phenylethynyl group, a maleimide group, a nadic imide group, and a (meth) acryloyl group. Among them, from the viewpoints of reactivity and resolution of the through-holes, (meth) acryl is preferable.

From the viewpoint of enabling alkali development, the component (a) is a component having an acidic substituent.

Examples of the acidic substituent of the component (A) include a carboxyl group, a sulfonic acid group, a phenolic hydroxyl group and the like. Among them, carboxyl groups are preferable from the viewpoint of resolution of the through holes.

(A) The acid value of the component is preferably 20 to 200mgKOH/g, more preferably 40 to 180mgKOH/g, still more preferably 70 to 150mgKOH/g, particularly preferably 90 to 120mgKOH/g. If the acid value of component (a) is equal to or higher than the lower limit, the solubility of the photosensitive resin film in a dilute alkali solution tends to be excellent, and if it is equal to or lower than the upper limit, the relative dielectric constant tends to be excellent. (A) The acid value of the component (a) can be measured by the method described in examples.

In this case, the weighted average acid value of the acid values of the two or more components (a) is preferably within any of the above ranges.

(A) The weight average molecular weight (Mw) of the component is preferably 600 to 30,000, more preferably 800 to 25,000, further preferably 1,000 to 18,000, further preferably 1,000 to 8,000, particularly preferably 1,200 to 5,000, and most preferably 1,200 to 3,500. If the weight average molecular weight (Mw) of the component (A) is in the above range, the adhesion strength with copper plating, heat resistance and insulation reliability tend to be excellent. Here, in the present specification, the weight average molecular weight is a value obtained by converting standard polystyrene by Gel Permeation Chromatography (GPC) using tetrahydrofuran as a solvent, and specifically, is a value measured according to the method described in examples.

From the viewpoint of the relative dielectric constant, the component (a) preferably contains an alicyclic skeleton.

The alicyclic skeleton of component (a) is preferably an alicyclic skeleton having 5 to 20 ring-forming carbon atoms, more preferably an alicyclic skeleton having 5 to 18 ring-forming carbon atoms, still more preferably an alicyclic skeleton having 6 to 18 ring-forming carbon atoms, particularly preferably an alicyclic skeleton having 8 to 14 ring-forming carbon atoms, and most preferably an alicyclic skeleton having 8 to 12 ring-forming carbon atoms, from the viewpoints of resolution of the through hole, adhesion strength to copper plating, and electrical insulation reliability.

The alicyclic skeleton is preferably formed of 2 or more rings, more preferably 2 to 4 rings, and still more preferably 3 rings, from the viewpoints of resolution of the through hole, adhesion strength to copper plating, and electrical insulation reliability. Examples of the alicyclic skeleton having 2 or more rings include a norbornane skeleton, a decalin skeleton, a bicycloundecane skeleton, and a saturated dicyclopentadiene skeleton. Among them, from the viewpoints of resolution of the through hole, adhesion strength to copper plating, and electrical insulation reliability, a saturated dicyclopentadiene skeleton is preferable.

From the same viewpoint, the component (A) preferably contains an alicyclic skeleton represented by the following general formula (A-1).

[ chemical 2]

(wherein R is ^A1 Represents an alkyl group having 1 to 12 carbon atoms, and may be substituted at any position in the alicyclic skeleton. m is m ¹ Is an integer of 0 to 6. Is a junction with other structures. )

In the above general formula (A-1), R is ^A1 Examples of the alkyl group having 1 to 12 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, and n-pentyl. 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 still more preferably a methyl group.

m ¹ Is an integer of 0 to 6Preferably an integer of 0 to 2, more preferably 0.

At m ¹ In the case of an integer of 2 to 6, a plurality of R ^A1 The two may be the same or different. Further, a plurality of R ^A1 May be substituted on the same carbon atom or on different carbon atoms as far as possible.

The bond site with other structure may be any carbon atom bonded to the alicyclic skeleton, but is preferably a carbon atom bonded to a site represented by 1 or 2 and a carbon atom bonded to a site represented by 3 or 4 in the following general formula (A-1').

[ chemical 3]

(wherein R is ^A1 、m ¹ And the same as in the general formula (A-1). )

From the viewpoints of resolution of the through hole and adhesion strength to the copper plating, the component (a) is preferably a compound obtained by modifying the epoxy resin (a 1) with the polybasic acid anhydride having a saturated group or an unsaturated group (a 3) and the organic acid having an ethylenic unsaturated group (a 2) [ hereinafter, sometimes referred to as component (a'). Acid modified vinyl-containing epoxy resin obtained by the reaction. Here, "acid-modified" of the acid-modified vinyl-containing epoxy resin means having an acidic substituent, "vinyl" means an ethylenically unsaturated group, "epoxy resin" means that the acid-modified vinyl-containing epoxy resin does not necessarily have an epoxy group or may not have an epoxy group, using the epoxy resin as a raw material.

Hereinafter, a preferred embodiment of the component (A) obtained from the epoxy resin (a 1), the organic acid having an ethylenic unsaturated group (a 2), and the polybasic acid anhydride having a saturated group or an unsaturated group (a 3) will be described.

((a 1) epoxy resin)

The epoxy resin (a 1) is preferably an epoxy resin having two or more epoxy groups.

(a1) The epoxy resin may be used alone or in combination of two or more.

(a1) The epoxy resin may be classified into a glycidyl ether type epoxy resin, a glycidyl amine type epoxy resin, a glycidyl ester type epoxy resin, and the like. Among them, glycidyl ether type epoxy resins are preferable.

(a1) The epoxy resin may be classified into various epoxy resins depending on the main skeleton, and may be classified into an epoxy resin having an alicyclic skeleton, a novolac type epoxy resin, a bisphenol type epoxy resin, an aralkyl type epoxy resin, other epoxy resins, and the like. Among them, epoxy resins having an alicyclic skeleton and novolak type epoxy resins are preferable.

Epoxy resins having alicyclic backbones

The alicyclic skeleton of the epoxy resin having an alicyclic skeleton can be described in the same manner as the alicyclic skeleton of the component (a), and the preferable mode is the same.

The epoxy resin having an alicyclic skeleton is preferably an epoxy resin represented by the following general formula (A-2).

[ chemical 4]

(wherein R is ^A1 An alkyl group having 1 to 12 carbon atoms may be substituted at any position in the alicyclic skeleton. R is R ^A2 Represents an alkyl group having 1 to 12 carbon atoms. m is m ¹ Is an integer of 0 to 6, m ² Is an integer of 0 to 3. n is a number from 0 to 50. )

In the general formula (A-2), R ^A1 And R in the general formula (A-1) ^A1 The same is preferable.

R as a component of the formula (A-2) ^A2 Examples of the alkyl group having 1 to 12 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, and n-pentyl. 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 still more preferably a methyl group.

General formula (A-2)) M in (b) ¹ And m in the general formula (A-1) ¹ The same is preferable.

M in the general formula (A-2) ² Is an integer of 0 to 3, preferably 0 or 1, more preferably 0.

N in the general formula (A-2) represents the number of repetition of the structural unit in parentheses and is a number of 0 to 50. In general, epoxy resins are mixtures of substances differing in the number of repetitions of the structural unit in parentheses, and therefore in this case n is represented by the average value of the mixture. N is preferably a number of 0 to 30.

As the epoxy resin having an alicyclic skeleton, commercially available ones can be used, and examples thereof include "XD-1000" (trade name, manufactured by Japanese chemical Co., ltd.), and "EPICLON (registered trademark) HP-7200" (trade name, manufactured by DIC Co., ltd.).

Novolak type epoxy resins

Examples of the novolak type epoxy resin include bisphenol novolak type epoxy resins such as bisphenol a novolak type epoxy resin, bisphenol F novolak type epoxy resin and bisphenol S novolak type epoxy resin; phenol novolac type epoxy resins, cresol novolac type epoxy resins, biphenyl novolac type epoxy resins, naphthol novolac type epoxy resins, and the like.

As the novolak type epoxy resin, an epoxy resin having a structural unit represented by the following general formula (A-3) is preferable.

[ chemical 5]

(wherein R is ^A3 Represents a hydrogen atom or a methyl group, Y ^A1 Each independently represents a hydrogen atom or a glycidyl group. Two R ^A3 The two may be the same or different. Two Y' s ^A1 At least one of which is a glycidyl group. )

From the viewpoint of resolution of the through hole and adhesion strength to the copper plating, R ^A3 Preferably hydrogen atoms. In addition, from the same view as the aboveConsidering in point, Y ^A1 Preferably glycidyl groups.

The number of structural units in the epoxy resin (a 1) having the structural unit represented by the general formula (A-3) is 1 or more, preferably 10 to 100, more preferably 15 to 80, and still more preferably 15 to 70. If the number of structural units is within the above range, the adhesion strength with copper plating, heat resistance and insulation reliability tend to be improved.

In the general formula (A-3), R ^A3 Are all hydrogen atoms and Y ^A1 Glycidyl groups are commercially available as EXA-7376 series (trade name, DIC Co., ltd.), and R ^A3 Are all methyl groups and Y ^A1 Glycidyl groups are commercially available as EPON SU8 series (trade name, manufactured by mitsubishi chemical corporation).

Examples of the bisphenol type epoxy resin include bisphenol a type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, 3', 5' -tetramethyl-4, 4' -diglycidyl oxy diphenylmethane, and the like.

Examples of the aralkyl type epoxy resin include phenol aralkyl type epoxy resins, biphenyl aralkyl type epoxy resins, naphthol aralkyl type epoxy resins, and the like.

Examples of the other epoxy resin include a stilbene type epoxy resin, a naphthalene skeleton-containing epoxy resin, a biphenyl type epoxy resin, a dihydro anthracene type epoxy resin, a cyclohexanedimethanol type epoxy resin, a trimethylol type epoxy resin, an alicyclic epoxy resin, an aliphatic chain type epoxy resin, a heterocyclic type epoxy resin, a spiro ring-containing epoxy resin, and a rubber modified epoxy resin.

((a 2) organic acid containing ethylenic unsaturated group)

The organic acid (a 2) containing an ethylenically unsaturated group is preferably a monocarboxylic acid containing an ethylenically unsaturated group.

Examples of the ethylenically unsaturated group contained in the component (a 2) include the same groups as those listed as the ethylenically unsaturated group contained in the component (a).

Examples of the component (a 2) include acrylic acid derivatives such as acrylic acid, acrylic acid dimer, methacrylic acid, β -furfurylacrylic acid, β -styrylacrylic acid, cinnamic acid, crotonic acid, and α -cyanocinnamic acid; a half-ester compound as a reaction product of a hydroxyl group-containing acrylate and a dibasic acid anhydride; and half ester compounds which are reaction products of vinyl group-containing monoglycidyl ethers or vinyl group-containing monoglycidyl esters and dibasic acid anhydrides.

(a2) The components may be used singly or in combination of two or more.

The half ester compound is obtained by reacting a dibasic acid anhydride with an ethylenically unsaturated group-containing compound selected from the group consisting of a hydroxyl group-containing acrylate, a vinyl group-containing monoglycidyl ether and a vinyl group-containing monoglycidyl ester. The reaction is preferably carried out by reacting the compound containing an ethylenic unsaturated group with a dibasic acid anhydride in equimolar amounts.

Examples of the hydroxyl group-containing acrylate used for the synthesis of the half ester compound include hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, trimethylolpropane di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, and the like.

Examples of the vinyl group-containing monoglycidyl ether include glycidyl (meth) acrylate.

The dibasic acid anhydride used for the synthesis of the half ester compound may contain a saturated group or an unsaturated group. Examples of the dibasic acid anhydride include succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride, and itaconic anhydride.

In the reaction of the component (a 1) and the component (a 2), the amount of the component (a 2) to be used is preferably 0.6 to 1.05 equivalents, more preferably 0.7 to 1.02 equivalents, and even more preferably 0.8 to 1.0 equivalents based on 1 equivalent of the epoxy group of the component (a 1). By reacting the component (a 1) and the component (a 2) in the above ratio, the polymerizability of the component (a) tends to be improved, and the resolution of the through-holes of the obtained photosensitive resin composition tends to be improved.

(a1) The component (a) and the component (a 2) are preferably dissolved in an organic solvent to perform the reaction.

The organic solvents include: ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; glycol ether compounds such as methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; esters such as ethyl acetate, butyl cellosolve acetate, and carbitol acetate; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha and solvent naphtha. The organic solvent may be used alone or in combination of two or more.

In the reaction of the component (a 1) and the component (a 2), a catalyst for promoting the reaction is preferably used. The catalyst may be exemplified by: amine catalysts such as triethylamine and benzyl methylamine; quaternary ammonium salt catalysts such as methyltriethylammonium chloride, benzyltrimethylammonium bromide, benzyltrimethylammonium iodide and the like; phosphine catalysts such as triphenylphosphine. Among them, phosphine catalysts are preferable, and triphenylphosphine is more preferable. The catalyst may be used alone or in combination of two or more.

In the case of using the catalyst, the amount thereof to be used is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, and even more preferably 0.1 to 2 parts by mass, relative to 100 parts by mass of the total of the component (a 1) and the component (a 2), from the viewpoint of obtaining a proper reaction rate.

In the reaction of the component (a 1) and the component (a 2), a polymerization inhibitor is preferably used for the purpose of preventing polymerization in the reaction. Examples of the polymerization inhibitor include hydroquinone, methyl hydroquinone, hydroquinone monomethyl ether, catechol, and pyrogallol. The polymerization inhibitor may be used alone or in combination of two or more.

When the polymerization inhibitor is used, the amount thereof is preferably 0.01 to 1 part by mass, more preferably 0.02 to 0.8 part by mass, and even more preferably 0.1 to 0.5 part by mass, based on 100 parts by mass of the total of the component (a 1) and the component (a 2).

The reaction temperature of the component (a 1) and the component (a 2) is preferably 60 to 150 ℃, more preferably 80 to 120 ℃, and even more preferably 90 to 110 ℃ from the viewpoint of carrying out the reaction homogeneously while obtaining sufficient reactivity.

As described above, when a monocarboxylic acid containing an ethylenically unsaturated group is used as the component (a 2), the component (a') obtained by reacting the component (a 1) with the component (a 2) is a component having a hydroxyl group formed by the ring-opening addition reaction of the epoxy group of the component (a 1) and the carboxyl group of the component (a 2). Then, by further reacting the component (a 3) with the component (a '), the hydroxyl group of the component (a') (including the hydroxyl group originally present in the component (a 1)) and the acid anhydride group of the component (a 3) can be half-esterified to obtain the acid-modified vinyl-containing epoxy resin.

((a 3) polybasic acid anhydride)

The component (a 3) may contain a saturated group or an unsaturated group. Examples of the component (a 3) include succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride, itaconic anhydride, and the like. Among them, tetrahydrophthalic anhydride is preferable from the viewpoint of resolution of the through hole. (a3) The components may be used singly or in combination of two or more.

In the reaction of the component (A ') and the component (a 3), for example, the acid value of the acid-modified vinyl-containing epoxy resin can be adjusted by reacting 0.1 to 1.0 equivalent of the component (a 3) with 1 equivalent of the hydroxyl group in the component (A').

The reaction temperature of the component (A') and the component (a 3) is preferably 50 to 150 ℃, more preferably 60 to 120 ℃, and even more preferably 70 to 100 ℃ from the viewpoint of carrying out the reaction homogeneously while obtaining sufficient reactivity.

The content of the component (a) in the photosensitive resin composition of the present embodiment is not particularly limited, but is preferably 10 to 80% by mass, more preferably 10 to 60% by mass, even more preferably 15 to 45% by mass, particularly preferably 15 to 35% by mass, and most preferably 20 to 35% by mass, based on the total amount of the resin components of the photosensitive resin composition, from the viewpoints of heat resistance, relative permittivity, and chemical resistance.

Thermosetting resin (B)

(B) The component is thermosetting resin. The component (B) does not contain the component (A).

The photosensitive resin composition of the present embodiment contains (B) the thermosetting resin, and thus has a tendency to improve adhesion strength with copper plating, insulation reliability, and heat resistance.

Examples of the thermosetting resin include epoxy resin, phenolic resin, unsaturated imide resin, cyanate resin, isocyanate resin, and benzo resinOxazine resins, oxetane resins, amino resins, unsaturated polyester resins, allyl resins, dicyclopentadiene resins, silicone resins, triazine resins, melamine resins, and the like. In addition, the resin is not particularly limited to these, and known thermosetting resins can be used. Among them, epoxy resin is preferable from the viewpoints of adhesion strength with copper plating, insulation reliability and heat resistance.

(B) The components may be used singly or in combination of two or more.

The epoxy resin is preferably an epoxy resin having two or more epoxy groups. The epoxy resin may be classified into a glycidyl ether type epoxy resin, a glycidyl amine type epoxy resin, a glycidyl ester type epoxy resin, and the like. Among these, glycidyl ether type epoxy resins are preferable.

The epoxy resins may be classified into various types of epoxy resins according to the main skeleton, and among the types of epoxy resins, the epoxy resins may be further classified as follows. Specifically, it can be classified into: bisphenol epoxy resins such as bisphenol a epoxy resin, bisphenol F epoxy resin, and bisphenol S epoxy resin; bisphenol novolac type epoxy resins such as bisphenol a novolac type epoxy resin and bisphenol F novolac type epoxy resin; novolac-type epoxy resins other than the bisphenol-type novolac-type epoxy resins, such as phenol novolac-type epoxy resins, cresol novolac-type epoxy resins, and biphenyl novolac-type epoxy resins; phenol aralkyl type epoxy resin; a stilbene type epoxy resin; naphthalene skeleton-containing epoxy resins such as naphthol novolac-type epoxy resins, naphthol aralkyl type epoxy resins, and naphthylene ether type epoxy resins; biphenyl type epoxy resin; biphenyl aralkyl type epoxy resins; xylene type epoxy resin; a dihydroanthracene type epoxy resin; alicyclic epoxy resins such as saturated dicyclopentadiene epoxy resins; a heterocyclic epoxy resin; epoxy resins containing spiro rings; cyclohexane dimethanol type epoxy resin; a trimethylol type epoxy resin; aliphatic chain epoxy resins; rubber modified epoxy resin; etc.

Among them, the epoxy resin preferably contains at least one selected from the group consisting of bisphenol-based epoxy resins, naphthalene skeleton-containing epoxy resins, and biphenyl aralkyl-type epoxy resins, more preferably contains at least one selected from the group consisting of naphthalene skeleton-containing epoxy resins and biphenyl aralkyl-type epoxy resins, particularly from the viewpoints of heat resistance, electrical insulation reliability, developability, and adhesion strength to copper plating.

The equivalent ratio of the acid substituent of the component (a) to the epoxy group of the component (B) [ epoxy group/acid substituent ] in the photosensitive resin composition of the present embodiment is not particularly limited, but is preferably 0.5 to 6.0, more preferably 0.7 to 4.0, still more preferably 0.8 to 2.0, particularly preferably 0.9 to 1.8, from the viewpoints of insulation reliability, relative dielectric constant, heat resistance and adhesion strength to copper plating.

The content of the component (B) in the photosensitive resin composition of the present embodiment is not particularly limited, but is preferably 1 to 50% by mass, more preferably 5 to 30% by mass, and even more preferably 10 to 25% by mass, based on the total amount of the resin components of the photosensitive resin composition, from the viewpoints of insulation reliability, relative dielectric constant, heat resistance, and adhesion strength to copper plating.

Crosslinking agent (C)

The photosensitive resin composition of the present embodiment preferably further contains a crosslinking agent as the component (C). The crosslinking agent is preferably a crosslinking agent having two or more ethylenically unsaturated groups and having no acidic substituent. The crosslinking agent is a component that reacts with an ethylenic unsaturated group of the component (a) to increase the crosslinking density of the photosensitive resin film after curing. Therefore, the photosensitive resin composition of the present embodiment tends to further improve heat resistance and relative permittivity by containing the crosslinking agent.

(C) The components may be used singly or in combination of two or more.

Examples of the component (C) include a difunctional monomer having 2 ethylenically unsaturated groups and a multifunctional monomer having 3 or more ethylenically unsaturated groups. The component (C) preferably contains the above-mentioned polyfunctional monomer.

Examples of the ethylenically unsaturated group contained in the component (C) include the same groups as the ethylenically unsaturated group contained in the component (A), and preferable groups are also the same.

Examples of the difunctional monomer include aliphatic di (meth) acrylates such as trimethylolpropane di (meth) acrylate, polypropylene glycol di (meth) acrylate, and polyethylene glycol di (meth) acrylate; di (meth) acrylates having an alicyclic skeleton such as dicyclopentadiene di (meth) acrylate and tricyclodecane dimethanol di (meth) acrylate; aromatic di (meth) acrylates such as 2, 2-bis (4- (meth) acryloyloxy polyethoxy polypropoxy phenyl) propane and bisphenol a diglycidyl ether di (meth) acrylate.

Among them, from the viewpoint of obtaining a lower relative dielectric constant, a di (meth) acrylate having an alicyclic skeleton is preferable, and tricyclodecane dimethanol diacrylate is more preferable.

Examples of the polyfunctional monomer include (meth) acrylate compounds having a skeleton derived from trimethylolpropane, such as trimethylolpropane tri (meth) acrylate; (meth) acrylate compounds having a skeleton derived from tetramethylolmethane, such as tetramethylolmethane tri (meth) acrylate and tetramethylolmethane tetra (meth) acrylate; (meth) acrylate compounds having a skeleton derived from pentaerythritol, such as pentaerythritol tri (meth) acrylate and pentaerythritol tetra (meth) acrylate; (meth) acrylate compounds having a skeleton derived from dipentaerythritol, such as dipentaerythritol penta (meth) acrylate and dipentaerythritol hexa (meth) acrylate; (meth) acrylate compounds having a skeleton derived from di (trimethylolpropane), such as di (trimethylolpropane) tetra (meth) acrylate; (meth) acrylate compounds having a diglycerol-derived skeleton, and the like. Among them, from the viewpoints of resolution of the through hole and adhesion strength to the copper plating, a (meth) acrylate compound having a skeleton derived from trimethylolpropane is preferable, and trimethylolpropane tri (meth) acrylate is more preferable.

Here, the term "a (meth) acrylate compound having a skeleton derived from XXX" (wherein XXX is a compound name.) means an ester of XXX and (meth) acrylic acid, and the ester also includes a compound modified with an alkyleneoxy group.

When the photosensitive resin composition of the present embodiment contains (C) the crosslinking agent, the content of (C) is not particularly limited, but is preferably 10 to 85 parts by mass, more preferably 25 to 80 parts by mass, still more preferably 35 to 75 parts by mass, and particularly preferably 35 to 60 parts by mass, relative to 100 parts by mass of the component (a) from the viewpoints of heat resistance and relative permittivity.

Elastomer (D)

The photosensitive resin composition of the present embodiment preferably further contains an elastomer as the component (D). The photosensitive resin composition of the present embodiment contains the elastomer (D), and thus the adhesion strength with copper plating tends to be further improved. Further, the photosensitive resin composition of the present embodiment contains the (D) elastomer, and thus the effect of "flexibility and decrease in adhesion strength to copper plating" due to deformation (internal stress) which may occur due to curing shrinkage of the (a) component is suppressed.

(D) The elastic body may be used alone or in combination of two or more.

(D) The elastomer may be an elastomer having a reactive functional group at a molecular end or in a molecular chain.

Examples of the reactive functional group include an acid anhydride group, an epoxy group, a hydroxyl group, a carboxyl group, an amino group, an amide group, an isocyanato group, an acrylic group, a methacrylic group, and a vinyl group. Among them, from the viewpoints of resolution of the through hole and adhesion strength to the copper plating, an acid anhydride group, an epoxy group, a hydroxyl group, a carboxyl group, an amino group, and an amide group are preferable, an acid anhydride group and an epoxy group are more preferable, and an acid anhydride group is still more preferable.

The acid anhydride group is preferably an acid anhydride group derived from phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methylnadic anhydride, nadic anhydride, glutaric anhydride, dimethylglutaric anhydride, diethylglutaric anhydride, succinic anhydride, methylhexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, or the like, and more preferably an acid anhydride group derived from maleic anhydride.

In the case where the elastomer (D) has an acid anhydride group, the number of acid anhydrides contained in 1 molecule is preferably 1 to 10, more preferably 3 to 10, and even more preferably 6 to 10 from the viewpoints of resolution and relative dielectric constant of the through hole.

The photosensitive resin composition of the present embodiment preferably contains an elastomer having an ethylenic unsaturated group and an acidic substituent as the (D) elastomer.

Examples of the acidic substituent and the ethylenic unsaturated group include the same groups as those of the acidic substituent and the ethylenic unsaturated group of the component (a). Among them, (D) the elastomer is preferably an elastomer having the acid anhydride group as an acidic substituent and having a 1, 2-vinyl group as an ethylenically unsaturated group described later.

Examples of the elastomer (D) include polybutadiene-based elastomer, polyester-based elastomer, styrene-based elastomer, olefin-based elastomer, urethane-based elastomer, polyamide-based elastomer, acrylic-based elastomer, silicone-based elastomer, and derivatives of these elastomers. Among them, polybutadiene-based elastomers are preferred from the viewpoint of improving the adhesion strength with copper plating and further improving the compatibility with resin components and solubility.

The polybutadiene-based elastomer may suitably be exemplified by an elastomer containing a 1, 2-vinyl group and having a structural unit of a 1, 4-trans body and a structural unit of a 1, 4-cis body.

As described above, the polybutadiene-based elastomer is preferably an acid anhydride-group-containing polybutadiene-based elastomer modified with acid anhydride, and more preferably a maleic anhydride-derived polybutadiene-based elastomer from the viewpoint of resolution of the through holes.

The polybutadiene-based elastomer is commercially available, and specific examples thereof include "POLYVEST (registered trademark) MA75", "POLYVEST (registered trademark) EP MA120" (trade name, manufactured by the above-mentioned winning company), "Ricon (registered trademark) 100", "Ricon (registered trademark) 130MA8", "Ricon (registered trademark) 131MA5", "Ricon (registered trademark) 131MA17", "Ricon (registered trademark) 184MA6" (trade name, manufactured by the above-mentioned Cray Valley company).

The polybutadiene-based elastomer may be an epoxy-containing polybutadiene from the viewpoint of adhesion strength to copper plating (hereinafter, sometimes referred to as epoxidized polybutadiene). ].

The epoxidized polybutadiene represented by the following general formula (D-1) is preferable from the viewpoints of adhesion strength to copper plating and flexibility.

[ chemical 6]

( Wherein a, b and c each represent a ratio of structural units in parentheses, a is 0.05 to 0.40, b is 0.02 to 0.30, c is 0.30 to 0.80, and a+b+c=1.00 and (a+c) > b is further satisfied. y represents the number of structural units in brackets and is an integer of 10 to 250. )

In the general formula (D-1), the order of bonding the structural units in brackets is different. That is, the structural units shown on the left, the structural units shown in the center, and the structural units shown on the right may be staggered, and if represented by (a), (b), and (c), respectively, there may be various binding sequences of- [ (a) - (b) - (c) ] - [ (a) - (b) - (c) - ] -, - [ (a) - (c) - (b) ] - [ (a) - (c) - (b) -, - [ (b) - (a) - (c) ] - [ (b) - (a) - (c) -, - [ (a) - (b) - (c) ] - [ (c) - (b) - (a) - ] -, - [ (a) - (b) - (a) ] - [ (c) - (b) - (c) -, - [ (c) - (b) - (c) ] - [ (b) - (a) - (a) - ] -, and the like.

From the viewpoints of adhesion strength to copper plating and flexibility, a is preferably 0.10 to 0.30, b is preferably 0.10 to 0.30, and c is preferably 0.40 to 0.80. From the same point of view, y is preferably an integer of 30 to 180.

Examples of the polyester-based elastomer include an elastomer obtained by polycondensing a dicarboxylic acid or a derivative thereof with a diol compound or a derivative thereof.

Examples of the dicarboxylic acid include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and naphthalene dicarboxylic acid, and aromatic dicarboxylic acids in which hydrogen atoms of aromatic nuclei thereof are substituted with methyl, ethyl, phenyl, and the like; aliphatic dicarboxylic acids having 2 to 20 carbon atoms such as adipic acid, sebacic acid, dodecanedicarboxylic acid, etc.; alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, and the like.

Examples of the diol compound include aliphatic diols such as ethylene glycol, 1, 3-propanediol, 1, 4-butanediol, 1, 6-hexanediol, and 1, 10-decanediol; alicyclic diols such as 1, 4-cyclohexanediol; bisphenol A, bis (4-hydroxyphenyl) methane, bis (4-hydroxy-3-methylphenyl) propane, resorcinol and other aromatic diols.

Further, as the polyester-based elastomer, a multiblock copolymer having an aromatic polyester (for example, polybutylene terephthalate) portion as a hard segment component and an aliphatic polyester (for example, polytetramethylene glycol) portion as a soft segment component is suitably exemplified. Multiblock copolymers are rated in various ways depending on the types, ratios, and molecular weights of the hard segments and the soft segments.

(D) The number average molecular weight of the elastomer is not particularly limited, but is preferably 10,000 ～ 80,000, which may be 20,000 ～ 70,000, 30,000 ～ 65,000, or 40,000 ～ 60,000. (D) The number average molecular weight of the elastomer was obtained by converting standard polystyrene by Gel Permeation Chromatography (GPC) using tetrahydrofuran as a solvent.

In the case where the photosensitive resin composition of the present embodiment contains (D) an elastomer, the content of (D) is not particularly limited, but is preferably 0.5 to 15% by mass, more preferably 1 to 10% by mass, still more preferably 1 to 8% by mass, and particularly preferably 3 to 8% by mass, based on the total amount of the resin components of the photosensitive resin composition, from the viewpoints of heat resistance and adhesion strength to copper plating.

Organic filler (E)

The photosensitive resin composition of the present embodiment may further contain an organic filler as the component (E). The photosensitive resin composition of the present embodiment contains (E) the organic filler, so that the photosensitive resin composition and the photosensitive resin film tend to have a low specific gravity, and the relative dielectric constant tends to be further lowered depending on the material.

(E) The component preferably contains resin particles formed of at least one selected from the group consisting of resins having fluorine atoms, polyethylene, polypropylene, polystyrene, polyphenylene ether, and silicone. Among them, from the viewpoint of the effect of reducing the relative dielectric constant, the component (E) preferably contains resin particles formed of a resin having fluorine atoms, and more preferably contains resin particles formed of Polytetrafluoroethylene (PTFE) resin.

The volume average particle diameter of the resin particles is not particularly limited, but is preferably 20 to 1,000nm, more preferably 30 to 800nm, still more preferably 50 to 500nm, and particularly preferably 100 to 300nm. The method for measuring the volume average particle diameter is as described above.

When the photosensitive resin composition of the present embodiment contains (E) the organic filler, the content of (E) is not particularly limited, but is preferably 1 to 45% by mass, more preferably 3 to 40% by mass, still more preferably 5 to 30% by mass, and particularly preferably 10 to 30% by mass, based on the total amount of the resin components of the photosensitive resin composition. If the content of the organic filler (E) is greater than or equal to the above lower limit value based on the total resin component of the photosensitive resin composition, the relative dielectric constant tends to be further reduced, and if it is less than or equal to the above upper limit value, the decrease in adhesion strength with copper plating tends to be suppressed.

In particular, in the case where the (E) organic filler contains resin particles made of a resin having a fluorine atom, the total amount of the (X) component and the (E) component is preferably 50% by volume or less, more preferably 45% by volume or less, and still more preferably 40% by volume or less based on the total amount of the resin components of the photosensitive resin composition, from the viewpoint of adhesion strength with copper plating. The lower limit value of the total amount of the component (X) and the component (E) is not particularly limited, but is preferably not less than 2% by volume, more preferably not less than 10% by volume, still more preferably not less than 20% by volume, and particularly preferably not less than 30% by volume, from the viewpoint of lowering the relative dielectric constant.

Curing agent (F)

The photosensitive resin composition of the present embodiment preferably further contains a curing agent as the component (F). The photosensitive resin composition of the present embodiment tends to further improve heat resistance, relative permittivity, and the like by containing (F) the curing agent.

(F) The curing agent may be used alone or in combination of two or more.

As the curing agent (F), the curing agent for the thermosetting resin (B) may be used. For example, when the thermosetting resin (B) is an epoxy resin, an epoxy resin curing agent is preferably used, and the epoxy resin curing agent includes guanamines such as acetoguanamine and benzoguanamine; polyamines such as diaminodiphenylmethane, m-xylylenediamine, diaminodiphenylsulfone, dicyandiamide, urea derivatives, melamine, and polybasic hydrazides; organic acid salts and/or epoxy adducts thereof; amine complexes of boron trifluoride; triazine derivatives such as ethyl diamino sym-triazine, 2, 4-diamino sym-triazine and 2, 4-diamino-6-xylyl sym-triazine; polyphenols such as polyvinyl phenol, polyvinyl phenol bromide, phenol novolac, alkylphenol novolac, and triazine ring-containing phenol novolac resins.

The polyphenol may be, for example, a modified polyphenol obtained by modification with melamine, benzoguanamine, or the like. The hydroxyl equivalent of the polyphenol is not particularly limited, but is preferably 40 to 300g/eq, may be 40 to 250g/eq, may be 60 to 200g/eq, may be 80 to 160g/eq, or may be 100 to 140g/eq. The hydroxyl equivalent (g/eq) can be determined by titration using an acetylation method using acetic anhydride.

When the photosensitive resin composition of the present embodiment contains (F) the curing agent, the content of the (F) curing agent is not particularly limited, but is preferably 0.01 to 10% by mass, more preferably 0.05 to 5% by mass, and even more preferably 0.1 to 1% by mass, based on the total amount of the resin components of the photosensitive resin composition, from the viewpoint of further improving the heat resistance and the relative dielectric constant.

(G) curing accelerator

The photosensitive resin composition of the present embodiment preferably further contains a curing accelerator as the (G) component. The photosensitive resin composition of the present embodiment tends to further improve heat resistance, relative permittivity, and the like by containing (G) a curing accelerator.

(G) The curing accelerator may be used alone or in combination of two or more.

The curing accelerator (G) may be: imidazole compounds such as 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 2-phenylimidazole, 2-phenyl-1-benzyl-1H-imidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and isocyanate-terminated imidazole (an addition reaction product of hexamethylene diisocyanate resin and 2-ethyl-4-methylimidazole); trimethylamine, N-dimethyloctylamine, N-benzyldimethylamine, pyridine, N-methylmorpholine, hexa (N-methyl) melamine, 2,4, 6-tris (dimethyl)Tertiary amines such as aminophenol), tetramethylguanidine, and m-aminophenol; organic phosphines such as tributylphosphine, triphenylphosphine and tri-2-cyanoethylphosphine; phosphonium salts such as tri-n-butyl (2, 5-dihydroxyphenyl) phosphonium bromide and cetyl tributyl phosphonium chloride; quaternary ammonium salts such as benzyl trimethyl ammonium chloride and phenyl tributyl ammonium chloride; the polybasic acid anhydride; diphenyliodoTetrafluoroborate, triphenylsulfonium->Hexafluoroantimonate, 2,4, 6-triphenylthiopyridine +.>Hexafluorophosphate salts, and the like.

Among them, imidazole compounds are preferable from the viewpoint of obtaining excellent curing action.

In the case where the photosensitive resin composition of the present embodiment contains (G) the curing accelerator, the content of the curing accelerator is not particularly limited, but is preferably 0.01 to 10% by mass, more preferably 0.05 to 5% by mass, and even more preferably 0.1 to 2% by mass, based on the total amount of the resin components of the photosensitive resin composition, from the viewpoint of further improving the heat resistance and the relative dielectric constant.

(H) photopolymerization initiator

The photosensitive resin composition of the present embodiment preferably further contains a photopolymerization initiator as the (H) component. The photosensitive resin composition of the present embodiment tends to further improve the resolution of the through holes by containing (H) a photopolymerization initiator.

(H) The photopolymerization initiator may be used alone or in combination of two or more. From the viewpoint of resolution of the through hole, the photosensitive resin composition of the present embodiment preferably contains two or more (H) components.

The photopolymerization initiator (H) is not particularly limited as long as it can photopolymerization an ethylenically unsaturated group, and may be appropriately selected from commonly used photopolymerization initiators.

Examples of the photopolymerization initiator (H) include benzoin compounds such as benzoin, benzoin methyl ether and benzoin isopropyl ether; acetophenone compounds such as acetophenone, 2-dimethoxy-2-phenylacetophenone, 2-diethoxy-2-phenylacetophenone, 1-dichloroacetophenone, 1-hydroxycyclohexylphenyl ketone, 2-benzyl-2-dimethylamino-1- (4-morpholinylphenyl) -1-butanone, 2- [4- (methylthio) benzoyl ] -2- (4-morpholinyl) propane, and N, N-dimethylaminoacetophenone; anthraquinone compounds such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-t-butylanthraquinone, 1-chloroanthraquinone, 2-pentylanthraquinone, and 2-aminoanthraquinone; ketal compounds such as acetophenone dimethyl ketal and benzil dimethyl ketal; acridine compounds such as 9-phenylacridine and 1, 7-bis (9, 9' -acridinyl) heptane; acyl phosphine oxide compounds such as bis (2, 4, 6-trimethylbenzoyl) phenylphosphine oxide; oxime ester compounds such as 1, 2-octanedione-1- [4- (phenylthio) phenyl ] -2- (O-benzoyl oxime), 1- [ 9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl ] ethanone 1- (O-acetyl oxime), and 1-phenyl-1, 2-propanedione-2- [ O- (ethoxycarbonyl) oxime.

Among them, oxime ester compounds and acylphosphine oxide compounds are preferable, and 1- [ 9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl ] ethanone 1- (O-acetyl oxime) and bis (2, 4, 6-trimethylbenzoyl) phenylphosphine oxide are more preferable. The oxime ester compound has an advantage of improving photocurability, and the acylphosphine oxide compound has an advantage of improving the degree of curing of the bottom of a cured product obtained by curing a photosensitive resin film and suppressing undercut. By using an oxime ester compound and an acylphosphine oxide compound in combination, the resolution of the via hole tends to be further improved.

When the photosensitive resin composition of the present embodiment contains (H) a photopolymerization initiator, the content of the (H) photopolymerization initiator is not particularly limited, but is preferably 0.01 to 20% by mass, more preferably 0.05 to 10% by mass, still more preferably 0.05 to 3% by mass, and particularly preferably 0.05 to 1.0% by mass, based on the total amount of the resin components of the photosensitive resin composition. If the content of (H) the photopolymerization initiator is not less than the above lower limit, the elution of the exposed portion during development tends to be reduced, and if it is not more than the above upper limit, the heat resistance tends to be improved.

Photosensitizing agent (I)

The photosensitive resin composition of the present embodiment may contain a photosensitizing agent as the component (I) as required.

(I) The photosensitizing agent may be used alone or in combination of two or more. The photosensitive resin composition of the present embodiment may contain two or more components (I) from the viewpoint of resolution of the through hole.

Examples of the photosensitizing agent (I) include thioxanthone compounds such as 2, 4-dimethylthioxanthone, 2, 4-diethylthioxanthone, 2-chlorothioxanthone, and 2, 4-diisopropylthioxanthone; tertiary amines such as trialkylamine and triethanolamine; dialkyl aminobenzoic acid alkyl esters such as ethyl N, N-dimethyl aminobenzoate and amyl N, N-dimethyl aminobenzoate; bis (dialkylamino) benzophenones such as 4,4 '-bis (dimethylamino) benzophenone and 4,4' -bis (diethylamino) benzophenone; phosphine compounds such as triphenylphosphine; toluidine compounds such as N, N-dimethyl toluidine; anthracene compounds such as 9, 10-dimethoxy anthracene, 2-ethyl-9, 10-diethoxy anthracene, and the like; a perylene compound; coumarin compounds, and the like.

The photosensitizing agent (I) is preferably bis (dialkylamino) benzophenone, more preferably 4,4' -bis (diethylamino) benzophenone, from the viewpoints of resolution of the via hole and improvement in the shape of the via hole.

When the photosensitive resin composition of the present embodiment contains (I) the photosensitizing agent, the content of (I) is not particularly limited, but is preferably 0.01 to 5% by mass, more preferably 0.05 to 3% by mass, still more preferably 0.1 to 1.5% by mass, and particularly preferably 0.1 to 1.0% by mass, based on the total amount of the resin components of the photosensitive resin composition. If the content of (I) the photosensitizing agent is not less than the lower limit, the degree of curing of the bottom of the cured product obtained by curing the photosensitive resin film tends to be sufficiently increased, and if it is not more than the upper limit, the degree of curing of the bottom of the cured product tends to be sufficiently decreased.

Additive (J)

The photosensitive resin composition of the present embodiment may contain an inorganic filler other than the component (X) as required; phthalocyanine blue, phthalocyanine green, iodine green, diazo yellow, crystal violet, titanium oxide, carbon black, naphthalene black, and the like; adhesion aids such as melamine; foam stabilizers such as organosilicon compounds; polymerization inhibitor; a tackifier; a flame retardant; and the like, and various additives conventionally known.

The content of the additive (J) may be appropriately adjusted according to the purpose, and is preferably 0.01 to 5% by mass, may be 0.05 to 3% by mass, or may be 0.1 to 1% by mass, based on the total amount of the resin components of the photosensitive resin composition.

< diluent >

The photosensitive resin composition of the present embodiment may contain a diluent as required. As the diluent, an organic solvent or the like can be used. Examples of the organic solvent include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; glycol ether compounds such as methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; esters such as ethyl acetate, butyl acetate, propylene glycol monoethyl ether acetate, butyl cellosolve acetate, and carbitol acetate; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha and solvent naphtha. The diluent may be used alone or in combination of two or more.

When the photosensitive resin composition of the present embodiment contains a diluent, the content of the diluent may be appropriately selected for the purpose of adjusting the concentration of the total amount of solid components in the photosensitive resin composition to a range of preferably 40 to 90 mass%, more preferably 50 to 85 mass%, and still more preferably 60 to 80 mass%. By adjusting the amount of the diluent to the above range, the coatability of the photosensitive resin composition is improved, and a higher-definition pattern can be formed.

The photosensitive resin composition of the present embodiment can be obtained by kneading and mixing the components by a roll mill, a bead mill, or the like.

The photosensitive resin composition of the present embodiment may be used in a liquid state (liquid state) or in a film state (film shape).

When used in a liquid state, the method of applying the photosensitive resin composition of the present embodiment is not particularly limited, and various application methods such as a printing method, a spin coating method, a spray dispensing method, an inkjet method, and a dip coating method can be exemplified. Among them, the printing method and the spin coating method are preferable from the viewpoint of easier formation of the photosensitive layer.

In the case of using the photosensitive resin film in a film form, for example, the photosensitive resin film may be used in a form described later, and in this case, a photosensitive layer having a desired thickness may be formed by laminating the photosensitive resin film on a carrier film by using a laminator or the like. In the case of using the multilayered printed wiring board in a film form, the multilayered printed wiring board is preferable because the production efficiency is high.

The photosensitive resin composition of the present embodiment is suitable for via formation by photolithography (also referred to as "via formation"), and therefore the present disclosure also provides a photosensitive resin composition for via formation composed of the photosensitive resin composition of the present embodiment.

[ photosensitive resin film ]

The photosensitive resin film of the present embodiment is a photosensitive resin film formed using the photosensitive resin composition of the present embodiment. The photosensitive resin film is useful as a photosensitive layer for forming an interlayer insulating layer.

The photosensitive resin film of the present embodiment may be provided on a carrier film.

The photosensitive resin film of the present embodiment can be formed by, for example, applying the photosensitive resin composition of the present embodiment to a carrier film using a known applicator such as a corner-roll coater, bar coater, kiss coater, roll coater, gravure coater, die coater, or the like, and drying the same.

Examples of the carrier film include polyesters such as polyethylene terephthalate and polybutylene terephthalate; polyolefins such as polypropylene and polyethylene. The thickness of the support film is preferably 5 to 100. Mu.m, more preferably 10 to 60. Mu.m, still more preferably 15 to 45. Mu.m.

The photosensitive resin film of the present embodiment may be provided with a protective film on a surface opposite to a surface in contact with the carrier film. As the protective film, a polymer film such as polyethylene or polypropylene can be used. The same polymer film as the carrier film may be used, or a different polymer film may be used.

The coating film formed by applying the photosensitive resin composition may be dried by hot air, a dryer using far infrared rays or near infrared rays, or the like. The drying temperature is preferably 60 to 150 ℃, more preferably 70 to 120 ℃, and even more preferably 80 to 110 ℃. The drying time is preferably 1 to 60 minutes, more preferably 2 to 30 minutes, and even more preferably 5 to 20 minutes. The content of the residual diluent in the photosensitive resin film after drying is preferably 3% by mass or less, more preferably 2% by mass or less, and even more preferably 1% by mass or less, from the viewpoint of avoiding the diffusion of the diluent in the production process of the multilayer printed wiring board.

The thickness (thickness after drying) of the photosensitive resin film (photosensitive layer) is not particularly limited, but is preferably 1 to 100 μm, more preferably 3 to 50 μm, and even more preferably 5 to 40 μm from the viewpoint of thickness reduction of the multilayer printed wiring board.

The photosensitive resin film of the present embodiment is suitable as an interlayer insulating layer of a multilayer printed wiring board because of excellent resolution of the through holes and adhesion strength to copper plating.

[ multilayer printed wiring board and method for producing the same ]

The multilayer printed wiring board of the present embodiment is a multilayer printed wiring board including an interlayer insulating layer formed using the photosensitive resin composition of the present embodiment or the photosensitive resin film of the present embodiment. Here, the expression "including an interlayer insulating layer" also includes a case where the interlayer insulating layer is directly included, and a case where the interlayer insulating layer is included in a state after various treatments such as processing such as formation of a via hole and roughening treatment, and wiring formation.

The method of manufacturing the multilayer printed wiring board of the present embodiment is not particularly limited as long as the multilayer printed wiring board has a step of forming an interlayer insulating layer using the photosensitive resin composition or the photosensitive resin film of the present embodiment, and can be manufactured more easily by the following method of manufacturing the multilayer printed wiring board of the present embodiment, for example.

A method for producing a multilayer printed wiring board using the photosensitive resin film of the present embodiment will be described with reference to fig. 1 as appropriate.

The multilayer printed wiring board 100A can be manufactured by a manufacturing method including the following (1) to (4), for example.

(1): the photosensitive resin film of the present embodiment is laminated on one or both surfaces of a circuit board (hereinafter referred to as "lamination step (1)").

(2): the photosensitive resin film laminated in the step (1) is exposed and developed to form an interlayer insulating layer having a through hole (hereinafter referred to as "optical through hole forming step (2)").

(3): the through-hole and the interlayer insulating layer are roughened (hereinafter referred to as "roughening step (3)").

(4): a circuit pattern is formed on the interlayer insulating layer (hereinafter referred to as "circuit pattern forming step (4)").

Here, as described above, the predetermined operation may be referred to as "XX process" for convenience in the present specification, but the "XX process" is not limited to the modes specifically described in the present specification.

(laminating step (1))

The lamination step (1) is a step of laminating the photosensitive resin film of the present embodiment on one or both sides of a circuit board (the board 101 having the circuit pattern 102) using a vacuum laminator. Examples of the vacuum laminator include a vacuum applicator manufactured by Nichigo-Morton corporation, a vacuum pressurizing laminator manufactured by the company name machine, a roll dry coater manufactured by the company Hitachi, and a vacuum laminator manufactured by the company Showa electric material electric Co.

When the protective film is provided on the photosensitive resin film, the protective film may be peeled off or removed, and then laminated by pressing and heating the photosensitive resin film against the circuit board while being in contact with the circuit board.

The lamination may be performed, for example, by preheating the photosensitive resin film and the circuit board as necessary, and then reducing the pressure at a pressure-bonding temperature of 70 to 130 ℃ and a pressure-bonding pressure of 0.1 to 1.0MPa and a gas pressure of 20mmHg (26.7 hPa) or less, but is not particularly limited to this condition. The lamination may be performed in a batch manner or a continuous manner using a roll.

Finally, the photosensitive resin film laminated on the circuit board is cooled to around room temperature, thereby producing the interlayer insulating layer 103. In the case where the photosensitive resin film has a carrier film, the carrier film may be peeled off at this point or may be peeled off after exposure as described later.

(optical Via Forming Process (2))

In the optical via forming step (2), at least a part of the photosensitive resin film laminated on the circuit board is exposed to light, followed by development. The pattern is formed by photo-curing the portion irradiated with the active light by exposure. The exposure method is not particularly limited, and for example, a method (mask exposure method) of irradiating an active light ray in an image form through a negative or positive mask pattern called an original image, or a method of irradiating an active light ray in an image form by a direct drawing exposure method such as an LDI (Laser Direct Imaging ) exposure method or a DLP (Digital Light Processing ) exposure method may be employed.

As the light source of the active light, a known light source can be used. Specific examples of the light source include a gas laser such as a carbon arc lamp, a mercury vapor arc lamp, a high-pressure mercury lamp, a xenon lamp, and an argon laser;solid state lasers such as YAG lasers; a semiconductor laser or the like is a laser that emits ultraviolet rays or visible rays efficiently. The exposure amount can be appropriately selected depending on the light source used, the thickness of the photosensitive layer, etc., and for example, when the thickness of the photosensitive layer is 1 to 100 μm in the case of irradiating ultraviolet rays from a high-pressure mercury lamp, it is usually preferably 10 to 1,000mJ/cm ² The extent is more preferably 50 to 700mJ/cm ² More preferably 150 to 550mJ/cm ² Particularly preferably 250 to 500mJ/cm ² 。

In development, the uncured portion of the photosensitive layer is removed from the substrate, so that the photo-cured portion is formed as an interlayer insulating layer on the substrate.

In the case where a carrier film is present on the photosensitive layer, removal (development) of an unexposed portion is performed after removal of the carrier film. The development method includes wet development and dry development, and wet development is widely used, but may be used in the present embodiment.

In the case of wet development, development is performed by a known development method using a developer corresponding to the photosensitive resin composition. Examples of the developing method include dipping, suspension dipping, spraying, brushing, beating, knife coating, and shaking dipping. Among them, the spray system is preferable from the viewpoint of improving the resolution of the through hole, and the high-pressure spray system is more preferable from the viewpoint of the spray system. The development may be performed by one method, but two or more methods may be performed in combination.

The composition of the developer can be appropriately selected according to the composition of the photosensitive resin composition. An alkaline aqueous solution, an aqueous developer, an organic solvent-based developer, and the like can be mentioned, and among these, an alkaline aqueous solution is preferable.

In the optical via hole forming step (2), exposure and development may be performed, and then, if necessary, 0.2 to 10J/cm may be performed ² Degree (preferably 0.5 to 5J/cm) ² ) The interlayer insulating layer is further cured by post UV curing at an exposure amount and post heat curing at a temperature of about 60 to 250 ℃ (preferably 120 to 200 ℃), and further preferably further cured.

By the above method, an interlayer insulating layer having the via hole 104 can be formed. The shape of the through hole is not particularly limited, and may be a quadrangle, an inverted trapezoid (upper side longer than lower side) or the like if it is described in terms of a cross-sectional shape, and a circle, a quadrangle or the like if it is described in terms of a shape as viewed from the front (the direction in which the bottom of the through hole is visible). In the formation of the through-hole by photolithography according to the present embodiment, a through-hole having an inverted trapezoidal cross-section (an upper side longer than a lower side) can be formed, and in this case, copper plating is preferable because the plating uniformity with respect to the through-hole wall surface is high.

The size (diameter) of the via hole formed in this step may be smaller than 40 μm, or may be smaller than 35 μm or smaller than 30 μm, and the size of the via hole may be smaller than that of the via hole formed by laser processing. The lower limit of the size (diameter) of the through hole formed in this step is not particularly limited, and may be 15 μm or more, or 20 μm or more.

However, the size (diameter) of the through hole formed by this step is not limited to be smaller than 40 μm, and may be arbitrarily selected in the range of 15 to 300 μm, for example.

(roughening treatment Process (3))

In the roughening treatment step (3), the surface of the via hole and the interlayer insulating layer is roughened with a roughening liquid. In the case where the photoresist residue is generated in the optical via forming step (2), the photoresist residue may be removed by the roughening liquid. The roughening treatment may be performed simultaneously with the removal of the cement (cement removal).

Examples of the roughening liquid include a chromium/sulfuric acid roughening liquid, an alkaline permanganate roughening liquid (for example, a sodium permanganate roughening liquid), and a sodium fluoride/chromium/sulfuric acid roughening liquid.

An anchor having irregularities is formed on the surfaces of the via hole and the interlayer insulating layer by roughening treatment.

(Circuit Pattern Forming Process (4))

The circuit pattern forming step (4) is a step of forming a circuit pattern on the interlayer insulating layer after the roughening treatment step (3).

From the viewpoint of forming fine wirings, the formation of the circuit pattern is preferably performed by a half-addition process. The formation of the circuit pattern and the conduction of the through hole are simultaneously performed through a half-addition process.

In the semi-additive process, first, electroless copper plating is performed using a palladium catalyst or the like on the entire surfaces of the via bottom, the via wall surface, and the interlayer insulating layer after the roughening treatment step (3), thereby forming the seed layer 105. The seed layer is preferably formed to a thickness of about 0.1 to 2.0 μm in order to form a layer for performing the electrolytic copper plating. If the thickness of the seed layer is 0.1 μm or more, the connection reliability at the time of copper plating tends to be suppressed, and if it is 2.0 μm or less, the etching amount at the time of flash etching of the seed layer between wirings does not need to be increased, and damage to wirings at the time of etching tends to be suppressed.

The electroless copper plating treatment is performed by depositing metallic copper on the surfaces of the via hole and the interlayer insulating layer by a reaction of copper ions and a reducing agent.

The electroless plating method and the electroplating method are not particularly limited as long as they are known methods.

As the electroless copper plating solution, commercially available ones can be used, and examples thereof include "MSK-DK" manufactured by Atotech Japan Co., ltd., and "THRU-CUP (registered trademark) PEA series" manufactured by Shangcun Industrial Co., ltd.

After the electroless copper plating treatment, a dry film resist was thermally pressed onto the electroless copper plating by a roll laminator. The dry film resist has to have a thickness higher than the wiring height after copper plating, and from this point of view, a dry film resist having a thickness of 5 to 30 μm is preferable. Examples of the dry film resist include "photo ec (registered trademark)" series manufactured by sho electric materials corporation.

After thermocompression bonding of the dry film resist, exposure of the dry film resist is performed, for example, through a mask on which a desired wiring pattern is drawn. The exposure can be performed by using the same device and light source as those used when the through-hole is formed in the photosensitive resin film. After exposure, development of the dry film resist is performed using an alkaline aqueous solution, and the unexposed portions are removed, thereby forming a resist pattern 106. Then, a process of removing the development residue of the dry film resist using plasma or the like may be performed as needed.

After the development, copper plating is performed, thereby forming a copper circuit layer 107 and filling the via holes.

After copper plating, the dry film resist is peeled off using an alkaline aqueous solution or an amine-based stripper. After the dry film resist is stripped, the seed layer between wirings is removed (flash etching). The flash etching is performed using an acidic solution such as sulfuric acid or hydrogen peroxide and an oxidizing solution. After the flash etching, palladium or the like attached to the portion between the wirings is removed as needed. The removal of palladium can be preferably performed using an acidic solution such as nitric acid or hydrochloric acid.

After the dry film resist is peeled off or after the flash etching step, a post-baking treatment is preferably performed. The post-baking treatment can sufficiently thermally cure the unreacted thermosetting component, and further tends to improve insulation reliability, curing characteristics, and adhesion strength to the copper plating. The heat curing conditions vary depending on the kind of the resin composition, etc., and it is preferable that the curing temperature is 150 to 240℃and the curing time is 15 to 100 minutes. The post-baking treatment completes the process of manufacturing the multilayer printed wiring board by the optical via method at a time, and the process is repeated according to the number of required interlayer insulating layers to manufacture the substrate. Further, the solder resist layer 108 is preferably formed on the outermost layer.

As described above, the method for manufacturing a multilayer printed wiring board in which a through hole is formed using the photosensitive resin composition of the present embodiment is also suitable for forming a cavity for incorporating, for example, a chip, a passive element, or the like, because the photosensitive resin composition of the present embodiment is excellent in pattern resolution. The cavity can be suitably formed by, for example, setting a drawing pattern in the case of exposing the photosensitive resin film to light to form a pattern in the description of the multilayer printed wiring board described above, as a pattern capable of forming a desired cavity.

[ semiconductor Package ]

The present disclosure also provides a semiconductor package including the multilayer printed wiring board of the present embodiment and a semiconductor element. The semiconductor package of the present embodiment can be manufactured by mounting a semiconductor element such as a semiconductor chip or a memory at a predetermined position on the multilayer printed wiring board of the present embodiment, and then sealing the semiconductor element with a sealing resin or the like.

Examples

Hereinafter, the present embodiment will be described in further detail with reference to examples, but the present disclosure is not limited to these examples. The acid value and weight average molecular weight of the component (a) were measured according to the following methods, and the true densities of the component (X), the component (X') and the component (E) were measured according to the following methods. The photosensitive resin compositions obtained in each example were evaluated for properties by the methods shown below.

< method for measuring acid value >)

(A) The acid value of the component (a) is calculated from the amount of the aqueous potassium hydroxide solution required for neutralization of the component (a).

Method for measuring weight average molecular weight

(A) The weight average molecular weight of the component (a) was measured under the following GPC measurement apparatus and measurement conditions, and the value obtained by conversion using a standard curve of standard polystyrene was set as the weight average molecular weight. In addition, for the preparation of the standard curve, 5 sample groups ("PStQuick MP-H" and "PStQuick B", manufactured by Tosoh corporation) were used as the standard polystyrene.

(GPC measurement apparatus)

GPC apparatus: a high-speed GPC apparatus "HCL-8320GPC", detector was a differential refractometer or UV, manufactured by Tosoh Co., ltd

Chromatographic column: TSKgel SuperMultipore HZ-H (column length: 15cm, column inner diameter: 4.6 mm), manufactured by Tosoh Corp.)

(measurement conditions)

Solvent: tetrahydrofuran (THF)

Measuring temperature: 40 DEG C

Flow rate: 0.35 ml/min

Sample concentration: 10mg/THF5ml

Injection amount: 20 μl of

< method for measuring true Density >)

1cm of the sample was measured on a dry automatic densitometer "AccuPycII 1340" (manufactured by Shimadzu corporation) ³ The sample cell is filled with the (X), (X') or (E) component until 8 minutes. The weight of the component filled in the sample cell was determined by measuring the weight of the sample cell filled with the component and subtracting the weight of the sample cell alone.

Next, a sample cell filled with the above-mentioned component is provided in the above-mentioned dry automatic densitometer, and then the weight of the component is inputted. After leaving the sample cell in place for 1 hour at room temperature under a nitrogen atmosphere, 10 measurements were performed to determine the average value. The average value was set to true density.

[1. Evaluation of relative permittivity (Dk) ]

Two photosensitive resin films from which protective films were peeled were bonded, and the film was exposed to a UV belt at a speed of 2J/cm using a UV belt type exposure machine in the state of having carrier films on both sides ² (wavelength 365 nm). The sample was subjected to heat treatment at 170℃for 1 hour in a warm air circulation dryer, and the obtained sample was cut into 7cm X10 cm pieces to obtain an evaluation sample.

The obtained evaluation sample was dried at 105℃for 10 minutes in a warm air circulation dryer, and then the relative dielectric constant (Dk) in the 10GHz band was measured by the separation column dielectric resonator method (SPDR method).

[2 ] evaluation of adhesion Strength to copper plating and evaluation of the presence or absence of plating Release ]

The protective film was peeled off from the "photosensitive resin film having a carrier film and a protective film bonded thereto" produced in each of examples and comparative examples, and laminated on a copper-clad laminate substrate having a thickness of 1.0mm using a press vacuum laminator (manufactured by the trade name "MVLP-500" manufactured by the trade name of the co. Ltd.) under conditions of a press pressure of 0.4MPa, a press hot plate temperature of 80 ℃, a vacuum time of 25 seconds, a lamination press time of 25 seconds, and a gas pressure of 4kPa or less, to obtain a laminate.

For the obtained laminate, use was made ofA parallel light exposure machine (trade name "EXM-1201" manufactured by ORC Co., ltd.) using an ultra-high pressure mercury lamp as a light source was used at 400mJ/cm ² (wavelength: 365 nm) to carry out a full-face exposure. Next, the ultraviolet exposure apparatus was used at 2,000mJ/cm ² After exposure to light at a wavelength of 365nm, the resultant was heated at 170℃for 1 hour to obtain a "laminate for evaluation" in which a cured product was formed on a copper-clad laminate substrate.

Next, diethylene glycol monobutyl ether is first prepared: 200ml/L, sodium hydroxide: after 5g/L of the aqueous solution was used as a swelling liquid, the temperature was raised to 70℃and the laminate for evaluation was immersed for 10 minutes. Then, potassium permanganate was prepared: 60g/L, sodium hydroxide: after 40g/L of the aqueous solution was used as the roughening liquid, the mixture was heated to 70℃and then the laminate for evaluation was subjected to impregnation treatment for 15 minutes. Next, a neutralization solution (tin chloride (SnCl) ₂ ): 30g/L, hydrogen chloride: 300 ml/L) was heated to 40 ℃, and then the evaluation laminate was immersed for 5 minutes to reduce potassium permanganate. The surface of the cured product of the laminate for evaluation was desmear treated as described above.

Next, the surface of the cured product of the evaluation laminate after desmutting treatment was treated with an alkaline cleaner "Cleaner Securiganth" 902 (trade name, manufactured by Atotech Japan Co., ltd.) at 60℃for 5 minutes, and then subjected to degreasing cleaning. After washing, the cured product subjected to desmear treatment was treated with a Pre-immersion liquid "Pre-dip Neogath B" (trade name, manufactured by Atotech Japan Co., ltd.) at 23℃for 1 minute. Then, the cured product was treated with an activating solution "Activator Neoganth 834" (trade name, manufactured by Atotech japan) at 35 ℃ for 5 minutes, and then, with a reducing solution "Reducer Neoganth WA" (trade name, manufactured by Atotech japan) at 30 ℃ for 5 minutes.

The laminate for evaluation thus obtained was placed in a chemical copper solution ("Basic Printganth MSK-DK", "Copper Printganth MSK" and "Stabilizer Printganth MSK" (all manufactured by Atotech Japan Co., ltd., trade name)), and electroless plating was performed until the plating thickness became about 0.5. Mu.m. After the electroless plating, an annealing treatment was performed at a temperature of 120 ℃ for 30 minutes in order to remove the residual hydrogen gas. Then, copper sulfate plating was performed, and annealing treatment was performed at 180℃for 60 minutes to form a conductor layer having a thickness of 25. Mu.m.

The laminate for evaluation having the conductor layer formed as described above was evaluated according to the following evaluation criteria by measuring the vertical peel strength at 23 ℃ in accordance with JIS C6481 (1996).

A: the adhesion strength with copper plating is more than or equal to 0.4kN/m.

B: the adhesion strength with copper plating is greater than or equal to 0.3kN/m and less than 0.4kN/m.

C: the adhesion strength to copper plating is more than 0.1kN/m and less than 0.3kN/m.

D: the adhesion strength with copper plating is less than or equal to 0.1kN/m.

Further, the surface of the laminate for evaluation after the annealing treatment was visually observed to confirm the presence or absence of plating peeling. When the plating peeling occurs, irregularities are generated on the plating surface, and when the plating peeling does not occur, the plating surface becomes flat.

[ preparation of photosensitive resin composition ]

Examples 1 to 5 and comparative examples 1 to 2

(1) Production of photosensitive resin composition

The compositions were blended according to the blending compositions shown in table 1 (the numerical values in the table are in parts by mass, and in the case of solutions, the solid content conversion amounts were measured), and then kneaded with a three-roll mill. Then, methyl ethyl ketone was added so that the solid content concentration became 65 mass%, thereby obtaining a photosensitive resin composition.

(2) Production of photosensitive resin film

A polyethylene terephthalate film (product name "G2-16" manufactured by Di people Co., ltd.) having a thickness of 16 μm was used as the carrier film. The photosensitive resin composition prepared in each example was applied to the carrier film while adjusting the film thickness to 25 μm after drying, and dried at 100℃for 10 minutes using a hot air convection dryer, thereby forming a photosensitive resin film (photosensitive layer). Next, a polyethylene film (trade name "NF-15" manufactured by tamopoly corporation) was attached as a protective film to the surface of the photosensitive resin film (photosensitive layer) opposite to the side where the support film was in contact with the photosensitive resin film, and a photosensitive resin film to which the support film and the protective film were attached was produced.

Each evaluation was performed by the above method using the prepared photosensitive resin film. The results are shown in Table 1.

TABLE 1

The unit of the content is parts by mass, and corresponds to a solid content conversion amount in the case of a solution or a dispersion.

The content indicated in parentheses is "volume%" based on the total amount of solid components "

The components used in table 1 are as follows.

[ (A) photopolymerizable Compound having an ethylenically unsaturated group and an acidic substituent ]

A1; "ZXR-1935H" (acid value; 110mgKOH/g, weight-average molecular weight; 2,000, manufactured by Japanese chemical Co., ltd.)

[ (B) thermosetting resin ]

B1; "EPOTOTE (registered trademark) ESN-475V" (Naphthol type epoxy resin, epoxy equivalent; 325g/eq, manufactured by Nitro iron chemical & materials Co., ltd.)

B2; "NC-3000L" (biphenyl aralkyl type epoxy resin, epoxy equivalent; 272g/eq, manufactured by Japanese chemical Co., ltd.)

[ (C) crosslinker ]

C1; "TMPTA" (trimethylolpropane triacrylate)

[ (D) elastomer ]

D1; "Ricon (registered trademark) 131MA17" (maleic-modified polybutadiene manufactured by Cray Valley Co., ltd.; number average molecular weight 54,000 (catalogue))

D2; "Ricon (registered trademark) 100" (butadiene-styrene random copolymer, manufactured by Cray Valley Co., ltd.; number average molecular weight 45,000 (catalogue value))

[ (X) true density less than or equal to 1,500kg/m ³ Inorganic filler material of (2)]

X1; the true density is 1,350kg/m ³ Spherical fused silica (volume average particle diameter; 0.7 μm)

X2; the true density is 1,350kg/m ³ Spherical fused silica (volume average particle diameter; 1.5 μm)

X3; the true density is 1,350kg/m ³ Spherical fused silica (volume average particle diameter; 3.0 μm)

[ (X') true density exceeding 1,500kg/m ³ Inorganic filler material of (2)]

X'1; the true density is 2,210kg/m ³ Spherical fused silica (volume average particle diameter; 0.5 μm)

[ (E) organic filler ]

PTFE; "M-7226EX" (volume average particle diameter; 200nm, manufactured by Send Chemie Co., ltd.)

[ (F) curing agent ]

F1; "PHENOLITE (registered trademark) LA7052" (Novolac type phenol resin modified with benzoguanamine, etc., available from DIC Co., ltd.; hydroxyl equivalent; 120 g/eq)

[ (G) curing accelerator ]

G1; 2-phenyl-1-benzyl-1H-imidazole (imidazole-based compound)

[ (H) photopolymerization initiator ]

H1;1- [ 9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl ] ethanone 1- (O-acetyl oxime) (oxime ester compound)

H2; bis (2, 4, 6-trimethylbenzoyl) phenylphosphine oxide (acylphosphine oxide-based compound)

[ (I) photosensitizers ]

I1;4,4' -bis (diethylamino) benzophenone

[ (J) additives ]

4-tert-butylcatechol; polymerization inhibitor

"SH-193" (silicone foam stabilizer, manufactured by Tao Kang Ningdong Co., ltd.)

As can be seen from table 1: example 1 of the present embodiment5 and the true density of the photosensitive resin composition was 2,210kg/m ³ The photosensitive resin composition of comparative example 1 of the inorganic filler (ii) can lower the relative dielectric constant while maintaining the adhesion strength to copper plating at a high level.

It is found that the photosensitive resin composition of comparative example 2, which contains PTFE in a large amount for the purpose of greatly reducing the relative dielectric constant, achieves the object, but the adhesion strength to copper plating is greatly reduced, and plating peeling is likely to occur.

Symbol description

100A multilayer printed wiring board

101 substrate

102 circuit pattern

103 interlayer insulating layer

104 through hole (via hole)

105 seed layer

106 resist pattern

107 copper circuit layer

108 a solder resist layer.

Claims

1. A photosensitive resin composition comprising (X) a true density of 1,500kg/m or less ³ Is a filler material for a ceramic material.

2. The photosensitive resin composition according to claim 1, wherein the volume average particle diameter of the component (X) is 0.3 to 3. Mu.m.

3. The photosensitive resin composition according to claim 1 or 2, wherein the content of the (X) component is 1 to 45% by volume based on the total solid content of the photosensitive resin composition.

4. The photosensitive resin composition according to any one of claims 1 to 3, further comprising: (A) A photopolymerizable compound having an ethylenic unsaturated group and an acidic substituent, and (B) a thermosetting resin.

5. The photosensitive resin composition according to claim 4, wherein the component (A) comprises an alicyclic skeleton represented by the following general formula (A-1),

[ chemical 1]

Wherein R is ^A1 An alkyl group having 1 to 12 carbon atoms which may be substituted at any position in the alicyclic skeleton, m ¹ Is an integer of 0 to 6, and is a bonding site with other structures.

6. The photosensitive resin composition according to claim 4 or 5, wherein the equivalent ratio of the acidic substituent of the component (A) to the epoxy group of the component (B), i.e., the epoxy group/acidic substituent, is 0.5 to 6.0.

7. The photosensitive resin composition according to any one of claims 1 to 6, further comprising (C) a crosslinking agent.

8. The photosensitive resin composition according to any one of claims 1 to 7, further comprising (D) an elastomer.

9. The photosensitive resin composition according to any one of claims 1 to 8, further comprising (E) an organic filler.

10. The photosensitive resin composition according to claim 9, wherein the component (E) contains resin particles formed of at least one selected from the group consisting of a resin having a fluorine atom, polyethylene, polypropylene, polystyrene, polyphenylene ether, and silicone.

11. The photosensitive resin composition according to claim 9 or 10, wherein the content of the component (E) is 1 to 45% by volume based on the total solid content of the photosensitive resin composition.

12. The photosensitive resin composition according to any one of claims 1 to 11, further comprising (H) a photopolymerization initiator.

13. The photosensitive resin composition according to claim 12, comprising two or more of the (H) components.

14. A photosensitive resin composition for forming an optical via, comprising the photosensitive resin composition according to any one of claims 1 to 13.

15. A photosensitive resin film formed using the photosensitive resin composition according to any one of claims 1 to 13.

16. A multilayer printed wiring board comprising an interlayer insulating layer formed using the photosensitive resin composition according to any one of claims 1 to 13 or the photosensitive resin film according to claim 15.

17. A semiconductor package comprising the multilayer printed wiring board of claim 16 and a semiconductor element.

18. A method for manufacturing a multilayer printed wiring board, comprising the following (1) to (4):

(1): laminating the photosensitive resin film according to claim 15 on one or both sides of a circuit substrate;

(2): exposing and developing the photosensitive resin film laminated in (1), thereby forming an interlayer insulating layer having a through hole;

(3): roughening the through hole and the interlayer insulating layer;

(4): a circuit pattern is formed on the interlayer insulating layer.