Photosensitive resin film, printed wiring board, and semiconductor package

Abstract

A photosensitive resin film, a printed wiring board using the same, and a semiconductor package, the photosensitive resin film containing (A) a photopolymerizable compound having an ethylenically unsaturated group and an acidic substituent and (B) an inorganic filler, the content of the (B) inorganic filler being 25 vol% or more, the refractive index of the cured product of the photosensitive resin film is greater than or equal to 1.550.

Description

Technical Field

[0001] The present invention relates to a photosensitive resin film, a printed wiring board and a semiconductor package. Background Art

[0002] In recent years, electronic devices have been miniaturized and improved in performance, and printed wiring boards have been increasingly densified due to the increase in the number of circuit layers and the miniaturization of wiring. In particular, the density of semiconductor package substrates such as BGA (ball grid array) and CSP (chip size package) equipped with semiconductor chips has increased significantly. In addition to miniaturization of wiring, it is also required to further reduce the diameter of the insulating layer and the through hole (also called via hole) used for interlayer connection.

[0003] As a conventional method for manufacturing a printed wiring board, there is a method for manufacturing a printed wiring board based on a build-up method in which an interlayer insulating layer and a conductor circuit layer are sequentially stacked (for example, see Patent Document 1). In printed wiring boards, as wiring becomes finer, a semi-additive method in which a circuit is formed by plating has become the mainstream.

[0004] 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 through holes for interlayer connection by laser processing, desmearing and roughening are performed by alkaline permanganate treatment or the like. (3) Then, after chemical copper plating is performed on the substrate, a pattern is formed using a resist, and then copper is electroplated to form a copper circuit layer. (4) Then, after the resist is stripped off, the chemically plated layer is flash-etched to form a copper circuit.

[0005] As described above, laser processing has become the mainstream method for forming through holes in an interlayer insulating layer formed by curing a thermosetting resin film, but the reduction in the diameter of through holes achieved by laser irradiation using a laser processing machine is reaching its limit. Furthermore, in the formation of through holes using a laser processing machine, each through hole needs to be formed one by one. In the case where a plurality of through holes need to be provided due to high density, the formation of the through holes requires a lot of time, resulting in a problem of poor manufacturing efficiency.

[0006] Under such circumstances, as a method for forming multiple through holes at a time, a method has been proposed in which a photosensitive resin composition containing an acid-modified vinyl epoxy resin, a photopolymerizable compound, a photopolymerization initiator, an inorganic filler and a silane compound, wherein the content of the inorganic filler is 10 to 80% by mass, is used to form multiple small-diameter through holes at a time by photolithography (for example, refer to Patent Document 2).

[0007] Patent document 2 discloses a material for an interlayer insulating layer or a surface protective layer, with one of the problems being to suppress the reduction in adhesion to the copper plating layer caused by using a photosensitive resin composition instead of a conventional thermosetting resin composition, and further solving these problems based on the problems of through-hole resolution and adhesion to a substrate of silicon raw materials and chip components.

[0008] Prior art literature

[0009] Patent Document 1: Japanese Patent Application Laid-Open No. 7-304931

[0010] Patent Document 2: Japanese Patent Application Publication No. 2017-116652 Summary of the invention

[0011] Problems to be solved by the invention

[0012] However, semiconductor packages contain organic components constituting insulating layers and inorganic components such as conductive layers and semiconductor chips, and therefore, due to the difference in thermal expansion coefficients between the organic and inorganic components, stress may be generated when the temperature changes, resulting in warping, cracks, etc. In order to suppress this, inorganic fillers are sometimes added to the resin composition used to form the insulating layer to make the thermal expansion coefficient close to that of the inorganic components.

[0013] However, according to the research conducted by the inventors, it has been found that: if a photosensitive resin film contains an inorganic filler, the shape of the through hole formed by exposing and developing the photosensitive resin film becomes a shape in which the diameter of the bottom of the through hole (hereinafter also referred to as the "bottom diameter") is too small relative to the diameter of the upper part of the through hole serving as the exposure surface (hereinafter also referred to as the "top diameter"), that is, the through hole becomes excessively conical when the through hole is cross-sectioned, and good resolution cannot be obtained.

[0014] Therefore, an object of the present invention is to provide a photosensitive resin film having excellent resolution, and a printed wiring board and a semiconductor package using the photosensitive resin film.

[0015] Means for solving problems

[0016] The present inventors have conducted intensive studies and have found that the above-mentioned object can be achieved by the present disclosure. That is, the present disclosure includes the following embodiments [1] to

[11] .

[0017] [1] A photosensitive resin film comprising (A) a photopolymerizable compound having an ethylenically unsaturated group and an acidic substituent and (B) an inorganic filler, wherein the content of the inorganic filler (B) is greater than or equal to 25% by volume, and the refractive index of a cured product of the photosensitive resin film is greater than or equal to 1.550.

[0018] [2] The photosensitive resin film according to [1] above, wherein the refractive index of the inorganic filler (B) is 1.520 to 1.680.

[0019] [3] The photosensitive resin film according to [1] or [2], wherein the inorganic filler (B) is composite particles of silicon dioxide and a metal oxide other than silicon dioxide.

[0020] [4] The photosensitive resin film according to [3] above, wherein the composite particles of silicon dioxide and a metal oxide other than silicon dioxide are silicon dioxide-titania composite particles.

[0021] [5] The photosensitive resin film according to any one of [1] to [4], wherein the (B) inorganic filler is spherical.

[0022] [6] The photosensitive resin film according to any one of [1] to [5] above, further comprising (C) a thermosetting resin.

[0023] [7] The photosensitive resin film according to any one of [1] to [6] above, further comprising (D) a crosslinking agent.

[0024] [8] The photosensitive resin film according to any one of [1] to [7] above, further comprising (E) a photopolymerization initiator.

[0025] [9] The photosensitive resin film according to any one of [1] to [8], which is used for forming a light through hole.

[0026]

[10] A printed wiring board comprising a cured product of the photosensitive resin film according to any one of [1] to [9] above.

[0027]

[11] A semiconductor package comprising the printed wiring board described in

[10] above and a semiconductor element.

[0028] Effects of the Invention

[0029] According to the present disclosure, a photosensitive resin film having excellent resolution, and a printed wiring board and a semiconductor package using the photosensitive resin can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] [ Figure 1 ] is a schematic diagram showing the lamination step (1).

[0031] [ Figure 2 ] is a schematic diagram showing the optical through hole forming step (2).

[0032] [ Figure 3 ] is a schematic diagram showing the roughening treatment step (3).

[0033] [ Figure 4 ] is a schematic diagram showing the circuit pattern forming step (4).

[0034] [ Figure 5 ] is a schematic diagram of a multilayered printed wiring board.

[0035] [ Figure 6 ] is a schematic diagram for explaining the cone angle. DETAILED DESCRIPTION

[0036] In the numerical range described in the present disclosure, the upper limit or lower limit of the numerical range can be replaced by the value shown in the embodiment. In addition, the lower limit and upper limit of the numerical range can be arbitrarily combined with the lower limit or upper limit of other numerical ranges, respectively. In the expression of the numerical range "AA to BB", the numerical values ​​AA and BB at both ends are included in the numerical range as the lower limit and upper limit, respectively.

[0037] In the present disclosure, for example, a statement such as "greater than or equal to 10" refers to 10 and a value greater than 10, and this applies even if the values ​​are different. In addition, for example, a statement such as "less than or equal to 10" refers to 10 and a value less than 10, and this applies even if the values ​​are different.

[0038] In the present disclosure, when there are plural substances corresponding to each component, the content of each component in the photosensitive resin film refers to the total content of the plural substances present in the photosensitive resin film unless otherwise specified.

[0039] In the present disclosure, "ring carbon number" refers to the number of carbon atoms required to form a ring, excluding the number of carbon atoms of substituents possessed by the ring. For example, the number of ring carbon atoms of a cyclohexane skeleton and a methylcyclohexane skeleton are both 6. In addition, "ring atoms" refers to the number of atoms required to form a ring, excluding the number of atoms of substituents possessed by the ring. For example, the number of ring atoms of a pyridine skeleton and a methylpyridine skeleton are both 6.

[0040] The expression "(meth)acrylate XX ester" means one or both of acrylate XX ester and methacrylate XX ester. In addition, "(meth)acryloyl group" means one or both of acryloyl group and methacryloyl group.

[0041] In the present disclosure, "resin component" refers to the component (A) described later, and also includes other components that may be contained as needed (such as components (C), (D), (E), (F), (G), etc.), but does not include inorganic compounds such as (B) inorganic fillers and (H) pigments. In addition, "solid content" refers to non-volatile components other than water contained in the photosensitive resin film and the diluent described later, and also includes components that are liquid at room temperature. Here, in this specification, room temperature refers to 25°C.

[0042] In addition, an embodiment in which the matters described in the present disclosure are arbitrarily combined is also included in the present embodiment.

[0043] [Photosensitive resin film]

[0044] The photosensitive resin film of this embodiment is a photosensitive resin film containing (A) a photopolymerizable compound having an ethylenically unsaturated group and an acidic substituent and (B) an inorganic filler, wherein the content of the above-mentioned (B) inorganic filler is greater than or equal to 25% by volume, and the refractive index of the cured product of the above-mentioned photosensitive resin film is greater than or equal to 1.550.

[0045] The photosensitive resin film of this embodiment is suitable for forming a through hole (also referred to as optical through hole formation) by photolithography, and is therefore suitable for forming one or more selected from the group consisting of an optical through hole and an interlayer insulating layer. Here, in the present disclosure, when a "layer" is expressed as an interlayer insulating layer, in addition to a solid layer, a layer in which at least a portion of the layer is island-shaped, a layer with holes, and a layer in which the interface with the adjacent layer is unclear are also included in the "layer". It should be noted that the solid layer refers to a sheet-like layer that has not been specially processed.

[0046] In addition, the photosensitive resin film of this embodiment is suitable for a negative photosensitive resin film.

[0047] <Refractive Index of Cured Photosensitive Resin Film>

[0048] The refractive index of the cured product of the photosensitive resin film of the present embodiment is 1.550 or more.

[0049] The photosensitive resin film of this embodiment has excellent resolution when the refractive index of the cured product is greater than or equal to 1.550. The reason is not yet clear, but it is speculated that when the refractive index of the cured product is greater than or equal to 1.550, the diffusion of energy rays incident on the photosensitive resin film during exposure is suppressed, and the curing of the light shielding portion is suppressed.

[0050] From the same viewpoint, the refractive index of the cured product of the photosensitive resin film of the present embodiment is preferably 1.551 to 1.680, more preferably 1.552 to 1.640, and even more preferably 1.553 to 1.600.

[0051] In addition, the refractive index of the cured product of the photosensitive resin film can be measured by the method described in Examples.

[0052] <(A) Photopolymerizable Compound Having an Ethylenically Unsaturated Group and an Acidic Substituent>

[0053] (A) Component is a photopolymerizable compound having an ethylenically unsaturated group and an acidic substituent.

[0054] (A) The component may be used alone or in combination of two or more.

[0055] The component (A) is a compound that exhibits photopolymerization, particularly radical polymerization, because it has an ethylenically unsaturated group.

[0056] Examples of the ethylenically unsaturated group possessed by the component (A) include photopolymerizable functional groups such as vinyl, allyl, propargyl, butenyl, ethynyl, phenylethynyl, maleimide, nadicimide, and (meth)acryloyl. Among them, (meth)acryloyl is preferred from the viewpoint of reactivity and through-hole resolution.

[0057] (A) Component has an acidic substituent from the viewpoint of enabling alkali development.

[0058] Examples of the acidic substituent possessed by the component (A) include a carboxyl group, a sulfonic acid group, and a phenolic hydroxyl group, among which a carboxyl group is preferred from the viewpoint of through-hole resolution.

[0059] The acid value of component (A) is preferably 20 to 200 mgKOH / g, more preferably 40 to 180 mgKOH / g, and further preferably 50 to 150 mgKOH / g. If the acid value of component (A) is greater than or equal to the above lower limit, the solubility of the photosensitive resin film in a dilute alkaline solution tends to be excellent, and if it is less than or equal to the above upper limit, the dielectric properties tend to be excellent. The acid value of component (A) can be measured by the method described in the examples.

[0060] In addition, two or more (A) components having different acid values ​​may be used in combination. In this case, the weighted average acid value of the acid values ​​of the two or more (A) components is preferably within any of the above ranges.

[0061] The weight average molecular weight (Mw) of the component (A) is preferably 600 to 30,000, more preferably 800 to 25,000, and further preferably 1,000 to 18,000. When the weight average molecular weight (Mw) of the component (A) is within the above range, there is a tendency for excellent bonding strength with the copper plating layer, heat resistance, and insulation reliability. Here, in the present disclosure, the weight average molecular weight is a value obtained by converting to standard polystyrene by gel permeation chromatography (GPC) using tetrahydrofuran as a solvent, and more specifically, a value measured by the method described in the Examples.

[0062] From the viewpoint of through-hole resolution and bonding strength with the copper plating layer, the component (A) is preferably an acid-modified vinyl-containing epoxy resin, which is obtained by reacting a compound obtained by modifying (a1) epoxy resin with (a2) an organic acid containing an ethylenically unsaturated group [hereinafter, sometimes referred to as the component (A')].] with (a3) ​​a polyacid anhydride containing a saturated group or an unsaturated group. Here, the "acid-modified" of the acid-modified vinyl-containing epoxy resin means having an acidic substituent, "vinyl" means an ethylenically unsaturated group, and "epoxy resin" means using an epoxy resin as a raw material. The acid-modified vinyl-containing epoxy resin does not necessarily need to have an epoxy group and may not have an epoxy group.

[0063] Hereinafter, preferred embodiments of the component (A) obtained from (a1) an epoxy resin, (a2) an organic acid containing an ethylenically unsaturated group, and (a3) ​​a polybasic acid anhydride containing a saturated group or an unsaturated group will be described.

[0064] ((a1) Epoxy resin)

[0065] As the (a1) epoxy resin, an epoxy resin having two or more epoxy groups is preferred.

[0066] (a1) The epoxy resin may be used alone or in combination of two or more.

[0067] (a1) Epoxy resins can be classified into glycidyl ether type epoxy resins, glycidyl amine type epoxy resins, glycidyl ester type epoxy resins, etc. Among them, glycidyl ether type epoxy resins are preferred.

[0068] (a1) Epoxy resins can also be classified into various epoxy resins according to the difference of the main skeleton, and can be classified into epoxy resins having an alicyclic skeleton, novolac epoxy resins, bisphenol epoxy resins, aralkyl epoxy resins, other epoxy resins, etc. Among them, epoxy resins having an alicyclic skeleton, novolac epoxy resins, and bisphenol epoxy resins are preferred, and novolac epoxy resins and bisphenol epoxy resins are more preferred.

[0069] Examples of the novolac epoxy resin include bisphenol novolac epoxy resins such as bisphenol A novolac epoxy resin, bisphenol F novolac epoxy resin, and bisphenol S novolac epoxy resin; phenol novolac epoxy resin, cresol novolac epoxy resin, biphenyl novolac epoxy resin, and naphthol novolac epoxy resin. Among them, cresol novolac epoxy resin is preferred.

[0070] Examples of the bisphenol epoxy resin include bisphenol A epoxy resin, bisphenol F epoxy resin, and bisphenol S epoxy resin. Among them, bisphenol A epoxy resin is preferred.

[0071] ((a2) Organic acid containing ethylenically unsaturated group)

[0072] As the (a2) ethylenically unsaturated group-containing organic acid, an ethylenically unsaturated group-containing monocarboxylic acid is preferred.

[0073] As the ethylenically unsaturated group which the component (a2) has, there may be mentioned the same groups as those exemplified as the ethylenically unsaturated group which the component (A) has.

[0074] Component (a2) includes acrylic acid derivatives such as acrylic acid, acrylic acid dimers, methacrylic acid, β-furfuryl acrylic acid, β-styryl acrylic acid, cinnamic acid, crotonic acid, and α-cyanocinnamic acid; half-ester compounds of reaction products of hydroxyl-containing acrylic acid esters and dibasic acid anhydrides; and half-ester compounds of reaction products of vinyl-containing monoglycidyl ethers or vinyl-containing monoglycidyl esters and dibasic acid anhydrides.

[0075] The component (a2) may be used alone or in combination of two or more.

[0076] In the reaction of component (a1) and component (a2), the amount of component (a2) used is preferably 0.6 to 1.05 equivalents, more preferably 0.7 to 1.02 equivalents, and still more preferably 0.8 to 1.0 equivalents relative to 1 equivalent of the epoxy group of component (a1). By reacting component (a1) and component (a2) at the above ratio, there is a tendency that the photopolymerizability of component (A) is improved and the through-hole resolution of the obtained photosensitive resin film is improved.

[0077] The components (a1) and (a2) are preferably dissolved in an organic solvent for reaction.

[0078] In the reaction between the components (a1) and (a2), a catalyst for accelerating the reaction, a polymerization inhibitor for preventing polymerization during the reaction, and the like may be used as necessary.

[0079] As described above, when a monocarboxylic acid containing an ethylenically unsaturated group is used as the component (a2), the component (A') obtained by reacting the components (a1) and (a2) has a hydroxyl group formed by a ring-opening addition reaction between the epoxy group of the component (a1) and the carboxyl group of the component (a2). Then, the component (A') is further reacted with the component (a3), thereby obtaining an acid-modified vinyl-containing epoxy resin in which the hydroxyl group of the component (A') (including the hydroxyl group originally present in the component (a1)) and the acid anhydride group of the component (a3) ​​are half-esterified.

[0080] ((a3) polybasic acid anhydride containing saturated or unsaturated groups)

[0081] As (a3) ​​component, it can contain saturated group, it can also contain unsaturated group. As (a3) ​​component, succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride, itaconic anhydride etc. can be listed. Among them, from the viewpoint of through-hole resolution, tetrahydrophthalic anhydride is preferred. (a3) ​​component can be used alone or in combination of two or more.

[0082] In the reaction between the components (A') and (a3), for example, 0.1 to 1.0 equivalent of the component (a3) ​​is reacted per 1 equivalent of the hydroxyl group in the component (A'), whereby the acid value of the acid-modified vinyl-containing epoxy resin can be adjusted.

[0083] The content of the component (A) in the photosensitive resin film of the present embodiment is not particularly limited, but is preferably 10 to 80% by mass, more preferably 30 to 70% by mass, and even more preferably 50 to 65% by mass, based on the total amount of the resin component of the photosensitive resin film, from the viewpoints of resolution, heat resistance, and chemical resistance.

[0084] <(B) Inorganic filler>

[0085] The photosensitive resin film of the present embodiment further contains an inorganic filler as the component (B).

[0086] The photosensitive resin film of the present embodiment contains the (B) inorganic filler, thereby having a low thermal expansion coefficient, and improving heat resistance and flame retardancy.

[0087] (B) The inorganic filler may be used alone or in combination of two or more.

[0088] (B) The inorganic filler is not particularly limited, and examples thereof include silica, aluminum oxide, titanium oxide, mica, beryllium oxide, barium titanate, potassium titanate, strontium titanate, calcium titanate, aluminum carbonate, magnesium hydroxide, aluminum hydroxide, aluminum silicate, calcium carbonate, calcium silicate, magnesium silicate, silicon nitride, boron nitride, clay, molybdate compounds, talc, aluminum borate, silicon carbide, and composite particles of two or more metal oxides.

[0089] Among them, composite particles of two or more metal oxides are preferred, and composite particles of silicon dioxide and a metal oxide other than silicon dioxide are more preferred, from the viewpoint of easily adjusting the refractive index of the cured product of the photosensitive resin film to a range of 1.550 or more.

[0090] As the metal oxide other than silicon dioxide in the composite particles of silicon dioxide and metal oxide other than silicon dioxide, for example, titanium dioxide (titanium oxide), zirconium dioxide (zirconium oxide), aluminum trioxide (aluminum oxide), boron oxide, calcium oxide, zinc oxide, etc. can be cited. Among them, from the viewpoint of easily adjusting the refractive index of the cured product of the photosensitive resin film to a range greater than or equal to 1.550, the metal oxide other than silicon dioxide is preferably titanium dioxide. That is, the composite particles of silicon dioxide and metal oxide other than silicon dioxide are preferably silicon dioxide titanium dioxide composite particles.

[0091] The volume average particle size of the component (B) is not particularly limited, but is preferably 0.01 to 20 μm, more preferably 0.1 to 10 μm, further preferably 0.2 to 1 μm, and particularly preferably 250 to 700 nm.

[0092] Here, in this specification, the volume average particle size is a value obtained by measuring particles dispersed in a solvent with a refractive index of 1.38 using a submicron particle analyzer (manufactured by Beckman Coulter, Ltd., trade name: N5) in accordance with international standard ISO13321, and is calculated as the particle size corresponding to the cumulative value of 50% (volume basis) in the particle size distribution.

[0093] The refractive index of the component (B) is not particularly limited, but is preferably 1.520 to 1.680, more preferably 1.530 to 1.640, and even more preferably 1.535 to 1.600.

[0094] Examples of the shape of the inorganic filler (B) include spherical shapes and crushed shapes. Of these, spherical shapes are preferred from the viewpoint of easily adjusting the refractive index of the cured product of the photosensitive resin film of the present embodiment to a range of 1.550 or more.

[0095] In addition, in this embodiment, "spherical" means that the circularity calculated by the following formula using the area and the perimeter measured from the photograph of the target particle is greater than or equal to 90.

[0096] Circularity = {4π×(area)÷(circumference) 2}×100

[0097] The particles can be observed using, for example, a scanning electron microscope (SEM) at 5,000 times magnification, and the average area value and the average perimeter value of any 10 particles can be used as the values ​​of the area and perimeter of the above formula, respectively.

[0098] (Content of component (B))

[0099] From the viewpoint of resolution and low thermal expansion, the content of the component (B) in the photosensitive resin film of this embodiment is greater than or equal to 25% by volume, preferably 30 to 80% by volume, more preferably 40 to 70% by volume, and further preferably 50 to 60% by volume.

[0100] From the viewpoint of achieving better resolution, the content of the component (B) in the photosensitive resin film of the present embodiment may be 26 to 55% by volume, 27 to 45% by volume, or 28 to 35% by volume.

[0101] From the viewpoint of resolution and low thermal expansion, the content of the component (B) in the photosensitive resin film of the present embodiment is preferably 40 to 90% by mass, more preferably 50 to 85% by mass, and even more preferably 60 to 80% by mass.

[0102] From the viewpoint of achieving better resolution, the content of the component (B) in the photosensitive resin film of the present embodiment may be 42 to 75% by mass, 43 to 65% by mass, or 45 to 55% by mass.

[0103] <(C) Thermosetting resin>

[0104] The photosensitive resin film of the present embodiment preferably further contains a thermosetting resin as the component (C). In addition, the component (C) does not contain the component (A).

[0105] The photosensitive resin film of the present embodiment contains (C) a thermosetting resin, thereby improving the bonding strength with the copper plating layer and the insulation reliability, and also tends to have improved heat resistance.

[0106] (C) The component may be used alone or in combination of two or more.

[0107] Examples of thermosetting resins include epoxy resins, phenolic resins, unsaturated imide resins, cyanate resins, isocyanate resins, benzoxazine resins, oxetane resins, amino resins, unsaturated polyester resins, allyl resins, dicyclopentadiene resins, silicone resins, triazine resins, and melamine resins. In addition, the above resins are not particularly limited, and known thermosetting resins can be used. Among them, epoxy resins are preferred from the viewpoints of bonding strength to the copper plating layer, insulation reliability, and heat resistance.

[0108] As the epoxy resin, an epoxy resin having two or more epoxy groups is preferred. Epoxy resins can be classified into glycidyl ether type epoxy resins, glycidyl amine type epoxy resins, glycidyl ester type epoxy resins, etc. Among them, glycidyl ether type epoxy resins are preferred.

[0109] In addition, epoxy resins can also be classified into various epoxy resins according to the difference of the main skeleton. Among the above-mentioned various types of epoxy resins, they can be further classified as follows. Specifically, they can be classified into bisphenol-based epoxy resins such as bisphenol A epoxy resin, bisphenol F epoxy resin, and bisphenol S epoxy resin; bisphenol-based novolac epoxy resins such as bisphenol A novolac epoxy resin and bisphenol F novolac epoxy resin; novolac epoxy resins other than the above-mentioned bisphenol-based novolac epoxy resins such as phenol novolac epoxy resin, cresol novolac epoxy resin, and biphenyl novolac epoxy resin; phenol aralkyl epoxy resin; stilbene epoxy resin; naphthol Epoxy resins containing naphthalene skeletons such as novolac epoxy resins, naphthol epoxy resins, naphthol aralkyl epoxy resins, and naphthylene ether epoxy resins; biphenyl epoxy resins; biphenyl aralkyl epoxy resins; benzyl dimethyl epoxy resins; dihydroanthracene epoxy resins; alicyclic epoxy resins such as saturated dicyclopentadiene epoxy resins; heterocyclic epoxy resins; spiro ring-containing epoxy resins; cyclohexanedimethanol epoxy resins; trimethylol epoxy resins; aliphatic chain epoxy resins; rubber-modified epoxy resins, etc. Among them, biphenyl aralkyl epoxy resins and biphenyl epoxy resins are preferred from the viewpoints of heat resistance, electrical insulation reliability, developability, and bonding strength to copper plating.

[0110] The equivalent ratio [epoxy group / acidic substituent] of the acidic substituent of the component (A) and the epoxy group of the component (C) in the photosensitive resin film of the present embodiment is not particularly limited, but is preferably 0.5 to 6.0, more preferably 0.7 to 4.0, further preferably 0.8 to 2.0, and particularly preferably 0.9 to 1.8 from the viewpoint of insulation reliability, dielectric properties, heat resistance, and adhesion strength to the copper plating layer.

[0111] When the photosensitive resin film of the present embodiment contains component (C), the content of component (C) is not particularly limited, but is preferably 1 to 50% by mass, more preferably 5 to 40% by mass, and even more preferably 15 to 40% by mass, based on the total amount of the resin component of the photosensitive resin film, from the viewpoints of insulation reliability, dielectric properties, heat resistance, and adhesion strength to the copper plating layer.

[0112] <(D) Cross-linking agent>

[0113] The photosensitive resin film of the present embodiment preferably further contains a crosslinking agent as component (D). As the crosslinking agent, it is preferably a crosslinking agent having two or more ethylenically unsaturated groups and having no acidic substituent. The crosslinking agent reacts with the ethylenically unsaturated groups possessed by component (A), thereby increasing the crosslinking density of the photosensitive resin film after curing. Therefore, the photosensitive resin film of the present embodiment has a tendency to improve heat resistance and dielectric properties by containing a crosslinking agent.

[0114] (D) The component may be used alone or in combination of two or more.

[0115] As the component (D), there can be mentioned a bifunctional monomer having two ethylenically unsaturated groups and a polyfunctional monomer having three or more ethylenically unsaturated groups. The component (D) preferably contains the above-mentioned polyfunctional monomer.

[0116] As the ethylenically unsaturated group which the component (D) has, there can be mentioned the same ones as the ethylenically unsaturated group which the component (A) has, and preferred aspects are also the same.

[0117] 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; and aromatic di(meth)acrylates such as 2,2-bis(4-(meth)acryloyloxypolyethoxypolypropoxyphenyl)propane and bisphenol A diglycidyl ether di(meth)acrylate.

[0118] Among them, from the viewpoint of obtaining more excellent dielectric properties, di(meth)acrylates having an alicyclic skeleton are preferred, and tricyclodecane dimethanol diacrylate is more preferred.

[0119] 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; (meth)acrylate compounds having a skeleton derived from dipentaerythritol, such as dipentaerythritol hexa(meth)acrylate; (meth)acrylate compounds having a skeleton derived from ditrimethylolpropane, such as ditrimethylolpropane tetra(meth)acrylate; (meth)acrylate compounds having a skeleton derived from diglycerol, and the like. Among them, from the viewpoint of through-hole resolution and bonding strength with the copper plating layer, a (meth)acrylate compound having a skeleton derived from dipentaerythritol is preferred, and dipentaerythritol hexa(meth)acrylate is more preferred.

[0120] Here, the above-mentioned “(meth)acrylate compound having a skeleton derived from XXX” (wherein XXX is a compound name) refers to an esterification product of XXX and (meth)acrylic acid, and the esterification product also includes compounds modified with an alkenyloxy group.

[0121] When the photosensitive resin film of the present embodiment contains component (D), the content of component (D) is not particularly limited, but is preferably 5 to 50 parts by mass, more preferably 10 to 40 parts by mass, and even more preferably 15 to 30 parts by mass, relative to 100 parts by mass of component (A), from the viewpoint of heat resistance and dielectric properties.

[0122] <(E) Photopolymerization Initiator>

[0123] The photosensitive resin film of the present embodiment preferably further contains a photopolymerization initiator as the component (E). The photosensitive resin film of the present embodiment tends to improve the through-hole resolution by containing the (E) photopolymerization initiator.

[0124] (E) The photopolymerization initiator may be used alone or in combination of two or more. From the viewpoint of through-hole resolution, the photosensitive resin film of the present embodiment preferably contains two or more components (E).

[0125] (E) The photopolymerization initiator is not particularly limited as long as it can photopolymerize an ethylenically unsaturated group, and can be appropriately selected from commonly used photopolymerization initiators.

[0126] (E) The photopolymerization initiator includes benzoin compounds such as benzoin, benzoin methyl ether, and benzoin isopropyl ether; acetophenone compounds such as acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)-1-butanone, 2-[4-(methylthio)benzoyl]-2-(4-morpholinyl)propane, and N,N-dimethylaminoacetophenone; 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, Anthraquinone compounds such as 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; acylphosphine oxide compounds such as bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide; oxime ester compounds such as 1,2-octanedione-[4-(phenylthio)phenyl]-2-(O-benzoyloxime), 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone-1-(O-acetyloxime), 1-phenyl-1,2-propanedione-2-[O-(ethoxycarbonyl)oxime], etc. Among them, 2-methyl-4'-methylthio-2-morpholinopropiophenone is preferred.

[0127] When the photosensitive resin film of the present embodiment contains component (E), the content of component (E) is not particularly limited, but is preferably 0.01 to 20% by mass, more preferably 0.05 to 10% by mass, and even more preferably 0.05 to 3% by mass, based on the total amount of the resin components of the photosensitive resin film, from the viewpoints of resolution and heat resistance.

[0128] <(F) Photosensitizer>

[0129] The photosensitive resin film of the present embodiment preferably contains a photosensitizer as the component (F), as necessary.

[0130] The (F) photosensitizer may be used alone or in combination of two or more. From the viewpoint of through-hole resolution, the photosensitive resin film of the present embodiment may contain two or more (F) components.

[0131] Examples of the (F) photosensitizer include thioxanthone compounds such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, and 2,4-diisopropylthioxanthone; tertiary amines such as trialkylamines and triethanolamine; dialkylaminobenzoic acid alkyl esters such as ethyl N,N-dimethylaminobenzoate and amyl N,N-dimethylaminobenzoate; 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-dimethyltoluidine; anthracene compounds such as 9,10-dimethoxyanthracene, 2-ethyl-9,10-dimethoxyanthracene, and 2-ethyl-9,10-diethoxyanthracene; perylene compounds; coumarin compounds, and the like. Among them, 2,4-diethylthioxanthone and 4,4′-bis(diethylamino)benzophenone are preferred from the viewpoint of improving the through-hole resolution and the through-hole shape.

[0132] When the photosensitive resin film of the present embodiment contains component (F), the content of component (F) is not particularly limited. From the viewpoint of easily adjusting the degree of curing of the photosensitive resin film to an appropriate range, the content is preferably 0.01 to 5% by mass, more preferably 0.05 to 3% 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 film.

[0133] <(G) Coupling agent>

[0134] The photosensitive resin film of the present embodiment preferably contains a coupling agent as the component (G), as necessary.

[0135] (G) The coupling agent may be used alone or in combination of two or more.

[0136] (G) Coupling agent includes aminosilane coupling agent, epoxysilane coupling agent, phenylsilane coupling agent, alkylsilane coupling agent, alkenylsilane coupling agent, alkynylsilane coupling agent, haloalkylsilane coupling agent, siloxane coupling agent, hydrogensilane coupling agent, silazane coupling agent, alkoxysilane coupling agent, chlorosilane coupling agent, (meth)acrylic silane coupling agent, isocyanurate silane coupling agent, urea silane coupling agent, mercapto silane coupling agent, sulfide silane coupling agent, isocyanate silane coupling agent, etc. Among them, (meth)acrylic silane coupling agent is preferred, and 3-methacryloxypropyltrimethoxysilane is more preferred.

[0137] When the photosensitive resin film of the present embodiment contains the component (G), the content of the component (G) is not particularly limited, but is preferably 0.01 to 5% by mass, more preferably 0.05 to 3% by mass, and further preferably 0.1 to 1% by mass based on the total amount of the resin components of the photosensitive resin film.

[0138] <(H) Pigments>

[0139] The photosensitive resin film of the present embodiment preferably contains a pigment as the component (H) as necessary.

[0140] (H) The pigment may be used alone or in combination of two or more.

[0141] (H) As the pigment, phthalocyanine blue, phthalocyanine green, iodine green, diazo yellow, crystal violet, titanium oxide, carbon black, naphthalene black, etc. can be mentioned.

[0142] When the photosensitive resin film of the present embodiment contains component (H), the content of component (H) is not particularly limited, but is preferably 0.01 to 5% by mass, more preferably 0.05 to 3% by mass, and further preferably 0.1 to 1.5% by mass based on the total amount of the resin components of the photosensitive resin film.

[0143] <(I) Other ingredients>

[0144] The photosensitive resin film of the present embodiment may contain other components such as an elastomer, an organic filler, a curing agent, a curing accelerator, an adhesion promoter, a foam stabilizer, a polymerization inhibitor, a thickener, and a flame retardant as needed.

[0145] The content of these components (I) may be appropriately adjusted depending on the purpose, and each is preferably 0.01 to 20% by mass, 0.05 to 10% by mass, or 0.1 to 1% by mass based on the total amount of the resin components of the photosensitive resin film.

[0146] <Thickness of Photosensitive Resin Film>

[0147] The thickness of the photosensitive resin film of the present embodiment 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 insulation and thinning of a printed wiring board.

[0148] <Application of photosensitive resin film>

[0149] The photosensitive resin film of the present embodiment is suitable for through-hole formation (also referred to as optical through-hole formation) by photolithography, and thus the present disclosure also provides a photosensitive resin film for optical through-hole formation composed of the photosensitive resin film of the present embodiment.

[0150] The photosensitive resin film of the present embodiment is useful as an interlayer insulating layer of a printed wiring board, and is also useful for solder resist applications.

[0151] <Method for producing photosensitive resin film>

[0152] The photosensitive resin film of the present embodiment can be produced by forming a photosensitive resin composition containing the components constituting the photosensitive resin film of the present embodiment into a film shape.

[0153] The photosensitive resin composition can be obtained by kneading and mixing the components using a roll mill, a bead mill, etc. From the viewpoint of easy coating, the photosensitive resin composition can be in the form of a varnish containing a diluent as needed.

[0154] As a method of forming a film of the photosensitive resin composition, a method of applying a varnish-like photosensitive resin composition on a carrier film and then drying it is preferred.

[0155] Examples of the carrier film include polyesters such as polyethylene terephthalate and polybutylene terephthalate, and polyolefins such as polypropylene and polyethylene. The thickness of the carrier film is preferably 5 to 100 μm, more preferably 7 to 50 μm, and even more preferably 10 to 30 μm.

[0156] Examples of a method for coating a varnish-like photosensitive resin composition on a carrier film include a method of coating using a known coating apparatus such as a notch wheel coater, a bar coater, a kiss coater, a roll coater, a gravure coater, and a die coater.

[0157] The drying after coating can be carried out by hot air drying, a dryer using far infrared rays or near infrared rays, etc. The drying temperature is preferably 60 to 150° C., more preferably 70 to 120° C., and further preferably 80 to 110° C. The drying time is preferably 1 to 60 minutes, more preferably 2 to 30 minutes, and further preferably 5 to 20 minutes.

[0158] The photosensitive resin film of this embodiment may be provided with a protective film on the surface opposite to the surface in contact with the carrier film. As the protective film, a polymer film such as polyethylene or polypropylene may be used.

[0159] [Printed wiring board]

[0160] The printed wiring board of the present embodiment includes a cured product of the photosensitive resin film of the present embodiment. In other words, it includes an interlayer insulating layer formed using the photosensitive resin film of the present embodiment. Here, the expression "including an interlayer insulating layer" includes the case where the interlayer insulating layer is directly included and the case where the interlayer insulating layer is included in a state where the interlayer insulating layer is subjected to various processes such as through-hole formation, roughening treatment, wiring formation, etc.

[0161] [Manufacturing method of printed wiring board]

[0162] A method for producing a printed wiring board according to one embodiment of the present disclosure (hereinafter, sometimes simply referred to as the present embodiment) is a method for producing a printed wiring board including the following (1) to (4).

[0163] (1): The photosensitive resin film of the present embodiment is laminated on one surface or both surfaces of a circuit board (hereinafter referred to as "lamination step (1)").

[0164] (2): The photosensitive resin film laminated in the above (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)").

[0165] (3): The surfaces of the through hole and the interlayer insulating layer are roughened (hereinafter referred to as "roughening step (3)").

[0166] (4): A circuit pattern is formed on the interlayer insulating layer (hereinafter referred to as "circuit pattern forming step (4)").

[0167] Here, in the present disclosure, as described above, for convenience, a predetermined operation may be referred to as "XX step" in some cases, but the XX step is not limited to the form specifically described in the present disclosure.

[0168] Hereinafter, each step will be described in sequence.

[0169] (Lamination process (1))

[0170] The lamination step (1) is a step of laminating the photosensitive resin film of this embodiment on one or both sides of a circuit substrate (substrate 101 having a circuit pattern 102) using a vacuum laminator (see Figure 1 ).

[0171] When a protective film is provided on the photosensitive resin film, after peeling or removing the protective film, the photosensitive resin film can be laminated by being pressed and bonded to the circuit board while being pressed and heated in a state where the photosensitive resin film is in contact with the circuit board.

[0172] The lamination can be performed, for example, after preheating the photosensitive resin film and the circuit board as needed, at a pressure-bonding temperature of 70 to 130° C., a pressure-bonding pressure of 0.1 to 1.0 MPa, and an air pressure of less than or equal to 20 mmHg (26.7 hPa), but is not particularly limited to these conditions. In addition, the lamination method can be intermittent or continuous using a roller.

[0173] Finally, the photosensitive resin film laminated on the circuit board is cooled to about 25° C. to form the interlayer insulating layer 103. When the photosensitive resin film has a carrier film, the carrier film may be peeled off here or after exposure as described later.

[0174] (Optical through hole forming step (2))

[0175] In the optical through hole forming step (2), at least a portion of the photosensitive resin film laminated on the circuit substrate is exposed and then developed. By exposure, the portion irradiated by the active light is photocured to form a pattern. The exposure method is not particularly limited. For example, a method of irradiating the active light in an image-like manner through a negative or positive mask pattern called an artwork (mask exposure method) can be adopted, or a method of irradiating the active light in an image-like manner by direct drawing exposure methods such as LDI (Laser Direct Imaging) exposure method and DLP (Digital Light Processing) exposure method can be adopted.

[0176] As the light source of active light, a known light source can be used. Specifically, as the light source, carbon arc lamps, mercury vapor arc lamps, high pressure mercury lamps, xenon lamps, gas lasers such as argon lasers, solid lasers such as YAG lasers, semiconductor lasers and other light sources that effectively radiate ultraviolet light or visible light can be cited. The exposure amount can be appropriately selected according to the light source used and the thickness of the photosensitive resin film. For example, in the case of ultraviolet irradiation from a high pressure mercury lamp, when the thickness of the photosensitive resin film is 1 to 100 μm, it is generally preferably 10 to 1,000 mJ / cm 2 More preferably, it is 50 to 700 mJ / cm 2 , more preferably 150 to 550 mJ / cm 2 , particularly preferably 250 to 500 mJ / cm 2 .

[0177] During the development, an uncured portion of the photosensitive resin film is removed from the substrate, so that a photocured portion is formed as an interlayer insulating layer on the substrate.

[0178] When there is a carrier film on the photosensitive layer, after removing the carrier film, the unexposed portion is removed (developed). There are two developing methods: wet development and dry development. Either method can be used, but wet development is widely used. In this embodiment, wet development can also be used.

[0179] In the case of wet development, a developer corresponding to the photosensitive resin film is used to develop by a known development method. As the development method, there can be cited an immersion method, a rotary immersion method, a spray method, a method using a brush, a pat, a scraper, a shaking immersion method, etc. Among them, from the viewpoint of improving the through-hole resolution, a spray method is preferred, and a high-pressure spray method is more preferred among the spray methods. Development can be implemented by one method or by combining two or more methods.

[0180] The structure of the developer can be appropriately selected according to the structure of the photosensitive resin film, and examples thereof include alkaline aqueous solutions, water-based developers, and organic solvent-based developers, among which alkaline aqueous solutions are preferred.

[0181] In the optical through hole forming step (2), after exposure and development, 0.2 to 10 J / cm 2 About (preferably 0.5 to 5 J / cm 2 ) and post-heat curing at a temperature of about 60 to 250° C. (preferably 120 to 200° C.) to further cure the interlayer insulating layer, and preferably further cure it.

[0182] The interlayer insulating layer having the through hole 104 is formed by the above method (see Figure 2 ).

[0183] The size of the through hole 104 formed by this process is not particularly limited, and can be, for example, 5 to 300 μm, 10 to 100 μm, or 15 to 80 μm. The photosensitive resin film of this embodiment is also suitable for forming small-diameter through holes due to its excellent resolution. From this point of view, the size of the through hole can be less than 40 μm, or less than or equal to 35 μm. It should be noted that the size of the through hole refers to the maximum length of the through hole when looking down at the interlayer insulating layer, and when the through hole is circular, it refers to the diameter.

[0184] (Roughening process (3))

[0185] In the roughening process step (3), the surface of the through hole and the interlayer insulating layer is roughened (see Figure 3). Fine concavo-convex anchor points are formed on the surface of the through hole and the interlayer insulating layer by roughening treatment.

[0186] The roughening method is not particularly limited, and a known roughening method for via holes and interlayer insulating layers can be used. The roughening method is not particularly limited, and examples thereof include a method using a roughening liquid and a method using dry etching.

[0187] (Circuit pattern forming step (4))

[0188] The circuit pattern forming step (4) is a step of forming a circuit pattern on the interlayer insulating layer after the roughening step (3) (see Figure 4 ).

[0189] From the viewpoint of forming fine wiring, the formation of the circuit pattern is preferably performed by a semi-additive process. By the semi-additive process, the circuit pattern is formed and the through-hole is connected at the same time.

[0190] After forming the circuit pattern, it is preferred to perform a post-baking treatment. The post-baking treatment can fully thermally cure the unreacted thermosetting components, thereby tending to improve insulation reliability, curing characteristics, and bonding strength with the copper plating layer. The thermal curing conditions vary depending on the type of the resin composition, etc., and preferably the curing temperature is 150 to 240° C. and the curing time is 15 to 100 minutes.

[0191] The post-baking process completes the entire manufacturing process of the printed wiring board 100A using the optical through hole method. This process is repeated according to the number of required interlayer insulation layers to manufacture the multilayered printed wiring board 100A (see Figure 5 ). Furthermore, a solder resist layer 108 is preferably formed on the outermost layer.

[0192] [Semiconductor packaging]

[0193] The present disclosure also provides a semiconductor package including the printed wiring board of this embodiment and a semiconductor element. The semiconductor package of this embodiment can be manufactured by mounting a semiconductor element such as a semiconductor chip or a memory on a predetermined position of the printed wiring board of this embodiment and then sealing the semiconductor element with a sealing resin or the like.

[0194] Example

[0195] Hereinafter, the present embodiment will be described in more detail by way of examples, but the present disclosure is not limited to these examples. It should be noted that the acid value and weight average molecular weight of the component (A) were measured by the following method. In addition, the photosensitive resin film obtained in each example was used to evaluate the properties by the method shown below.

[0196] <Method for measuring acid value>

[0197] The acid value of the component (A) is calculated from the amount of the potassium hydroxide aqueous solution required to neutralize the component (A).

[0198] <Method for measuring weight average molecular weight>

[0199] The weight average molecular weight of component (A) was measured by the following GPC measuring device and measuring conditions, and the value converted using the calibration curve of standard polystyrene was used as the weight average molecular weight. In addition, the preparation of the calibration curve used 5 sample groups ("PStQuick MP-H" and "PStQuick B", manufactured by Tosoh Corporation) as standard polystyrene.

[0200] (GPC measurement device)

[0201] Equipment: High-speed GPC equipment "HCL-8320GPC", detector is differential refractometer or UV, manufactured by Tosoh Corporation

[0202] Column: Column TSKgel SuperMultipore HZ-H (column length: 15cm, column inner diameter: 4.6mm), manufactured by Tosoh Corporation

[0203] (Measurement conditions)

[0204] Solvent: Tetrahydrofuran (THF)

[0205] Measurement temperature: 40℃

[0206] Flow rate: 0.35ml / min

[0207] Sample concentration: 10mg / THF 5ml

[0208] Injection volume: 20μl

[0209] <Method for measuring the refractive index of cured product of photosensitive resin film>

[0210] While peeling off the protective film from the "photosensitive resin film with a carrier film and a protective film" manufactured in each example, a pressurized vacuum laminator (manufactured by Meiki Manufacturing Co., Ltd., trade name "MVLP-500") was used to laminate the exposed photosensitive resin film onto a silicon wafer under the conditions of a pressing pressure of 0.4 MPa, a pressing hot plate temperature of 80°C, a vacuuming time of 25 seconds, a lamination pressing time of 25 seconds, and an air pressure of less than or equal to 4 kPa.

[0211] Next, a parallel light exposure machine (manufactured by ORC Manufacturing Co., Ltd., trade name "EXM-1201") using an ultra-high pressure mercury lamp as a light source was used to expose the sample at 200 mJ / cm 2(wavelength 365nm) The entire surface of the photosensitive resin film is exposed from the carrier film side, and the carrier film is peeled off after exposure. A matching liquid is applied to the surface of the exposed cured product of the photosensitive resin film so that it is in close contact with the prism, and the refractive index of the cured product of the photosensitive resin film on the silicon wafer is measured under the following conditions. It should be noted that the refractive index measurement conditions are as follows.

[0212] ·Measurement device: manufactured by Metricon Co., Ltd., trade name "Model 2010 / M PRISM COUPLER"

[0213] Wavelength: 632.8nm

[0214] ·Measurement temperature: 25℃

[0215] ·Measurement atmosphere: Air

[0216] Matching liquid: manufactured by Cargile Laboratories Inc., trade name "IMMERSION LIQUID (nD = 1.640)"

[0217] <Resolution Evaluation>

[0218] The through hole of the insulating layer formed in each example was observed using a scanning electron microscope (manufactured by Hitachi High-Tech Fielding Co., Ltd., trade name "SU5000") to measure the top diameter and bottom diameter of the through hole. The taper angle was calculated from the top diameter T, bottom diameter B of the through hole and the thickness X of the insulating layer by the following formula.

[0219] Cone angle θ(°) = tan -1 (2X / (TB))

[0220] It should be noted that the cone angle is Figure 6 As shown, the closer the angle θ in the through hole 104 formed in the insulating layer 103 is to 90°, the better the resolution is.

[0221] Examples 1 to 7, Comparative Examples 1 to 2

[0222] (1) Production of photosensitive resin composition

[0223] The composition was prepared according to the composition shown in Table 1 (the numerical units in the table are parts by mass, and in the case of a solution, the amount is calculated as solid content), and kneaded using a three-roll mill. Methyl ethyl ketone was then added so that the solid content concentration became 65% by mass to obtain a photosensitive resin composition.

[0224] (2) Production of photosensitive resin film

[0225] A polyethylene terephthalate film (manufactured by Toyobo Co., Ltd., trade name "HPES0") with a thickness of 25 μm was used as a carrier film. The photosensitive resin composition prepared in each example was coated on the carrier film, and the film thickness after drying was adjusted to 18 μm, and dried at 100° C. for 10 minutes using a hot air convection dryer to form a photosensitive resin film. Next, a polyethylene film (manufactured by TAMAPOLY Co., Ltd., trade name "NF-13") was attached as a protective film to the surface of the photosensitive resin film on the opposite side of the side in contact with the carrier film, thereby preparing a photosensitive resin film with a carrier film and a protective film.

[0226] (3) Formation of insulating layer

[0227] (Lamination process)

[0228] While peeling off the protective film from the "photosensitive resin film with a carrier film and a protective film" manufactured by the above method, a pressing vacuum laminator (manufactured by Meiki Manufacturing Co., Ltd., trade name "MVLP-500") was used to laminate on a copper-clad laminate substrate with a thickness of 1.0 mm under the conditions of a pressing pressure of 0.4 MPa, a pressing hot plate temperature of 80°C, a vacuuming time of 25 seconds, a lamination pressing time of 25 seconds, and an air pressure of less than or equal to 4 kPa to obtain an evaluation laminate.

[0229] (Optical Via Hole Forming Process)

[0230] The evaluation laminate was exposed from the carrier film using an i-ray stepper (UX-7, manufactured by Ushio Electric Co., Ltd.) using a step exposure meter and a mask for through-hole evaluation at an exposure amount (wavelength 365 nm) shown in Table 1. Then, after peeling off the carrier film, the laminate was developed using a spray developer at 30° C. with a 1% by mass sodium carbonate aqueous solution for the development time shown in Table 1, thereby forming a circular through hole having a diameter of 60 μm in a plan view of the evaluation laminate.

[0231] [Table 1]

[0232]

[0233] The components used in Table 1 are as follows.

[0234] [(A) Photopolymerizable Compound Having Ethylenically Unsaturated Group and Acidic Substituent]

[0235] A1: Acid-modified vinyl-containing epoxy resin obtained by reacting a compound obtained by modifying cresol novolac epoxy resin with acrylic acid with 1,2,3,6-tetrafluorophthalic anhydride, acid value: 60 mgKOH / g, weight average molecular weight: 6,000-7,000

[0236] A2: Bisphenol A type acid-modified epoxy acrylate (manufactured by Nippon Kayaku Co., Ltd., trade name "ZAR-2002H", acid value: 61 mgKOH / g)

[0237] [(B) Inorganic filler]

[0238] B1: Silica-titania particles (volume average particle size: 500 nm, refractive index: 1.541, shape: spherical)

[0239] B2: Silica-titania particles (volume average particle size: 300 nm, refractive index: 1.542, shape: spherical)

[0240] B3: Silica-titania particles (volume average particle size: 300 nm, refractive index: 1.573, shape: spherical)

[0241] B4: Silica-titania particles (volume average particle size: 300 nm, refractive index: 1.592, shape: spherical)

[0242] B5: Spherical fused silica (volume average particle size: 500 nm, refractive index: 1.46, shape: spherical)

[0243] B6: Spherical silica particles (volume average particle size: 300 nm, refractive index: 1.46, shape: spherical)

[0244] [(C) Thermosetting resin]

[0245] C1: "NC-3000L" (manufactured by Nippon Kayaku Co., Ltd., biphenyl aralkyl type epoxy resin, epoxy equivalent: 272 g / eq)

[0246] C2: "YX-4000" (manufactured by Mitsubishi Chemical Corporation, biphenyl type epoxy resin, epoxy equivalent: 186 g / eq)

[0247] [(D) Cross-linking agent]

[0248] D1: “DPHA” (dipentaerythritol hexaacrylate)

[0249] [(E) Photopolymerization initiator]

[0250] ·E1: 2-Methyl-4'-methylthio-2-morpholinopropiophenone

[0251] [(F) Photosensitizer]

[0252] ·F1: 4,4'-Bis(diethylamino)benzophenone

[0253] ·F2: 2,4-Diethylthioxanthone

[0254] [(G) Coupling agent]

[0255] ·G1: "KBM-503" (manufactured by Shin-Etsu Silicone Co., Ltd., 3-methacryloxypropyltrimethoxysilane)

[0256] [(H) Pigment]

[0257] H1: Blue pigment

[0258] H2: Yellow pigment

[0259] As can be seen from Table 1, the photosensitive resin films of Examples 1 to 7 of the present embodiment have large taper angles and are excellent in resolution.

[0260] Description of Reference Numerals

[0261] 100A: Printed wiring board

[0262] 101: Substrate

[0263] 102: Circuit pattern

[0264] 103: Interlayer insulation layer

[0265] 104: Through hole (conducting hole)

[0266] 105: Seed layer

[0267] 106: Resist pattern

[0268] 107: Copper circuit layer

[0269] 108: Solder mask

[0270] T: Top diameter of the through hole

[0271] B: Bottom diameter of the through hole

[0272] X: The thickness of the insulation layer.

Claims

1. A photosensitive resin film comprising (A) a photopolymerizable compound having an ethylenically unsaturated group and an acidic substituent and (B) an inorganic filler, The content of the inorganic filler (B) is greater than or equal to 25% by volume, The refractive index of the cured product of the photosensitive resin film is greater than or equal to 1.

550. 2 . The photosensitive resin film according to claim 1 , wherein the refractive index of the (B) inorganic filler is 1.520 to 1.

680. 3 . The photosensitive resin film according to claim 1 , wherein the (B) inorganic filler is composite particles of silicon dioxide and a metal oxide other than silicon dioxide. 4 . The photosensitive resin film according to claim 3 , wherein the composite particles of silicon dioxide and a metal oxide other than silicon dioxide are silicon dioxide-titania composite particles. The photosensitive resin film according to claim 1 or 2, wherein the (B) inorganic filler is spherical. 6 . The photosensitive resin film according to claim 1 , further comprising (C) a thermosetting resin. 7 . The photosensitive resin film according to claim 1 , further comprising (D) a crosslinking agent. 8 . The photosensitive resin film according to claim 1 , further comprising (E) a photopolymerization initiator. 9 . The photosensitive resin film according to claim 1 , which is used for forming a light through hole. 10 . A printed wiring board comprising a cured product of the photosensitive resin film according to claim 1 .

11. A semiconductor package comprising the printed wiring board according to claim 10, and a semiconductor element.

Images