Adhesive film, adhesive film with metal layer, member for forming wiring, method for forming wiring layer, and wiring formation member

Abstract

The present invention provides an adhesive film comprising an epoxy resin and a phenol resin, wherein the epoxy equivalent of the epoxy resin is not more than 150 g / eq. The present invention provides an adhesive film with a metal layer, said adhesive film comprising a metal layer and an adhesive layer that is disposed on the metal layer, wherein the adhesive layer contains an epoxy resin and a phenol resin, and the epoxy equivalent of the epoxy resin is not more than 150 g / eq. The present invention provides a member which is for forming wiring, which includes an adhesive layer and a metal layer that are separately provided, and in which the adhesive layer can be adhered to the metal layer when the member is used, wherein the adhesive layer contains an epoxy resin and a phenol resin, and the epoxy equivalent of the epoxy resin is not more than 150 g / eq.

Description

Adhesive film, adhesive film with a metal layer, member for forming a wiring, method for forming a wiring layer, and wiring forming member 【0001】 The present disclosure relates to an adhesive film, an adhesive film with a metal layer, a member for forming a wiring, a method for forming a wiring layer, and a wiring forming member. 【0002】 Patent Document 1 discloses a method for manufacturing a printed wiring board incorporating an electronic component such as an IC chip. 【0003】 Japanese Unexamined Patent Application Publication No. 2012 - 191204 【0004】 In a conventional method for manufacturing a component - incorporated substrate, as shown in FIGS. 8(a) and (b), insulating resin layers 102 and 103 are formed on both sides in the stacking direction of an electronic component 101 provided with electrodes 101a. Then, as shown in FIGS. 8(c) and (d), via electrodes 104 and 105 leading to each electrode 101a of the electronic component 101 are formed in each of the insulating resin layers 102 and 103 by performing laser drilling, forming a plating layer, and electrode formation by etching, etc. And, as shown in FIGS. 9(a) to (c), by repeating the formation of further insulating resin layers 106 and 107, the formation of via electrode 108 by laser drilling and forming a plating layer, and electrode formation by etching, etc., a component - incorporated substrate 110 is formed. However, in such a method for manufacturing a component - incorporated substrate, many processes are performed to form one conductive layer (via electrode), and these processes need to be repeated to form a plurality of conductive layers, and the manufacturing process is very complicated. 【0005】 Therefore, an adhesive having a metal layer such as a metal foil laminated thereon and having conductive particles was considered as a member for forming a wiring. According to such a member for forming a wiring, by going through a step of arranging the member for forming a wiring so that the adhesive layer faces the substrate on the surface where the wiring of the substrate is formed, a step of thermocompression - bonding the member for forming a wiring to the substrate, and a step of performing a patterning process on the metal layer, it can be expected to simply form a wiring layer connected to the wiring on the substrate on which the wiring is formed. 【0006】Incidentally, in the aforementioned component-embedded substrates used in semiconductor packages and the like, the components may be subjected to loads due to thermal expansion under high-temperature environments such as reflow processing. When excessive load occurs on the connection portion formed as described above, problems arise such as increased connection resistance due to poor conductivity, blistering, and delamination. On the other hand, wiring-forming components are required to have mechanical properties such as film toughness from the viewpoint of productivity and handling, such as for application in roll-to-roll processes. Furthermore, film toughness during winding is also necessary when slitting the component to a predetermined width. However, adhesive layers with resin designs that can form heat-resistant connection portions tend to have difficulty improving film toughness. 【0007】 Therefore, the present disclosure aims to provide an adhesive film having sufficient heat resistance (high Tg and low CTE) and film toughness, an adhesive film with a metal layer having sufficient heat resistance and film toughness, a wiring-forming member, a method for forming a wiring layer using these, and a wiring-forming member. 【0008】This disclosure includes, for example, the following aspects: [1] An adhesive film comprising an epoxy resin and a phenolic resin, wherein the epoxy equivalent of the epoxy resin is 150 g / eq or less. [2] The adhesive film according to [1], further comprising conductive particles. [3] The adhesive film according to [2], wherein the conductive particles are copper particles. [4] The adhesive film according to any one of [1] to [3], wherein the epoxy resin has three or more epoxy groups. [5] The adhesive film according to any one of [1] to [4], wherein the epoxy resin is pentaerythritol glycidyl ether. [6] An adhesive film with a metal layer comprising a metal layer and an adhesive layer disposed on the metal layer, wherein the adhesive layer comprises an epoxy resin and a phenolic resin, wherein the epoxy equivalent of the epoxy resin is 150 g / eq or less. [7] The adhesive film with a metal layer according to [6], further comprising conductive particles. [8] The adhesive film with a metal layer according to [7], wherein the conductive particles are copper particles. [9] The adhesive film with a metal layer according to any one of [6] to [8], wherein the epoxy resin has three or more epoxy groups.

[10] The adhesive film with a metal layer according to any one of [6] to [9], wherein the epoxy resin is pentaerythritol glycidyl ether.

[11] The adhesive film with a metal layer according to any one of [6] to

[10] , used for forming wiring.

[12] A wiring forming member comprising an adhesive layer and a metal layer, wherein the adhesive layer can be bonded to the metal layer during use, wherein the adhesive layer contains an epoxy resin and a phenolic resin, and the epoxy equivalent of the epoxy resin is 150 g / eq or less.

[13] The wiring forming member according to

[12] , further comprising conductive particles.

[14] The wiring forming member according to

[13] , wherein the conductive particles are copper particles.

[15] The wiring forming member according to any one of

[12] to

[14] , wherein the epoxy resin has three or more epoxy groups.

[16] The wiring forming member according to any one of

[12] to

[15] , wherein the epoxy resin is pentaerythritol glycidyl ether.

[17] A method for forming a wiring layer, comprising the steps of: preparing a metal-layered adhesive film according to any one of [6] to

[10] ; preparing a substrate on which wiring is formed; arranging the metal-layered adhesive film on the surface of the substrate on which the wiring is formed so as to cover the wiring, with the adhesive layer facing the substrate; heat-pressing the metal-layered adhesive film to the substrate; and performing a patterning treatment on the metal layer.

[18] A method for forming a wiring layer, comprising the steps of: preparing a wiring-forming member according to any one of

[12] to

[15] ; preparing a substrate on which wiring is formed; arranging the wiring-forming member on the surface of the substrate on which the wiring is formed so as to cover the wiring, with the adhesive layer facing the substrate; heat-pressing the wiring-forming member to the substrate; and performing a patterning treatment on the metal layer.

[19] A wiring forming member comprising a substrate having wiring, and a cured product of the adhesive layer of a metal layer adhesive film according to any one of [6] to

[10] , which is disposed on the substrate so as to cover the wiring, wherein the wiring and the metal layer of the metal layer adhesive film or another wiring formed from the metal layer are electrically connected.

[20] A wiring forming member comprising a substrate having wiring, and a cured product of the adhesive layer of a wiring forming member according to any one of

[12] to

[15] , which is disposed on the substrate so as to cover the wiring, wherein the wiring and the metal layer of the wiring forming member or another wiring formed from the metal layer are electrically connected. 【0009】 According to this disclosure, it is possible to provide an adhesive film having sufficient heat resistance (high Tg and low CTE) and film toughness, an adhesive film with a metal layer having sufficient heat resistance and film toughness, a wiring-forming member, a method for forming a wiring layer using these, and a wiring-forming member. 【0010】Figure 1 is a cross-sectional view showing a wiring-forming member according to one embodiment of the present disclosure. Figures 2(a) to 2(d) are diagrams illustrating, in order, a method for forming a wiring layer using the wiring-forming member shown in Figure 1. Figures 3(a) to 3(c) are cross-sectional views showing a wiring-forming member according to another embodiment of the present disclosure and the state when those wiring-forming members are crimped together. Figure 4 is a cross-sectional view showing a wiring-forming member according to another embodiment of the present disclosure. Figures 5(a) to 5(d) are diagrams illustrating, in order, a method for forming a wiring layer using the wiring-forming member shown in Figure 4. Figures 6(a) to 6(b) are cross-sectional views illustrating an example of a case where a wiring layer is formed using the wiring-forming member shown in Figure 4. Figures 7(a) to 7(b) are cross-sectional views illustrating another example of a case where a wiring layer is formed using the wiring-forming member shown in Figure 4. Figures 8(a) to 8(d) are cross-sectional views illustrating, in order, a conventional method for manufacturing a component-embedded substrate. Figures 9(a) to 9(c) are cross-sectional views illustrating, in order, a conventional method for manufacturing a component-embedded substrate, and show the steps following those in Figure 8. 【0011】 Hereinafter, with reference to the drawings, a metal-layered adhesive film and a wiring-forming member according to one embodiment of the present disclosure, as well as a method for forming a wiring layer using these, and the adhesive film will be described. In the following description, the same or equivalent parts will be denoted by the same reference numerals, and redundant explanations will be omitted. Furthermore, unless otherwise specified, positional relationships such as up, down, left, and right will be based on the positional relationships shown in the drawings. Moreover, the dimensional ratios in the drawings are not limited to those shown. 【0012】 In this specification, numerical ranges indicated using "~" include the numbers before and after "~" as the minimum and maximum values, respectively. Furthermore, in numerical ranges described in stages in this specification, the upper or lower limit of one numerical range may be replaced with the upper or lower limit of another numerical range described in stages. Also, in numerical ranges described in this specification, the upper or lower limit of that numerical range may be replaced with the values ​​shown in the examples. 【0013】The adhesive film with a metal layer of this embodiment comprises a metal layer and an adhesive layer disposed on the metal layer, wherein the adhesive layer contains an epoxy resin (epoxy compound) and a phenolic resin, and the epoxy equivalent of the epoxy resin is 150 g / eq or less. The adhesive film according to this embodiment can provide an adhesive film having sufficient heat resistance (high Tg and low CTE) and film toughness. The inventors speculate, but are not limited to, the following reasons for this. That is, epoxy resins with a relatively small epoxy equivalent have a small molecular weight and a large number of functional groups, resulting in a high crosslink density after curing. As a result, the glass transition temperature (Tg) of the cured product is improved, increasing heat resistance, and thermal expansion is suppressed, achieving a low coefficient of thermal expansion (CTE). Generally, high crosslink density leads to embrittlement, but in the adhesive film according to this embodiment, by containing a phenolic resin, the free volume between molecular chains can be appropriately controlled, and film toughness can be ensured. 【0014】 The adhesive film with a metal layer of this embodiment can be used to form wiring. In other words, the adhesive film with a metal layer of this embodiment may also be a wiring-forming member. The details of the adhesive film with a metal layer of this embodiment will be described below, with an example of its use as a wiring-forming member. 【0015】 Figure 1 is a cross-sectional view showing a wiring-forming member according to one embodiment of the present disclosure. As shown in Figure 1, the wiring-forming member 1 comprises an adhesive layer 10 and a metal layer 20. The wiring-forming member 1 is not limited to these, but can be used, for example, when manufacturing a rewiring layer, a build-up multilayer wiring board, and a component-embedded substrate. The wiring-forming member 1 may also be used for EMI shielding and the like. The wiring-forming member 1 is obtained by placing the adhesive layer 10 on the metal layer 20. 【0016】The adhesive layer 10 includes conductive particles 12 and an insulating adhesive component 14 in which the conductive particles 12 are dispersed. The adhesive component 14 of the adhesive layer 10 is defined as solid components other than conductive particles, such as the conductive particles 12. The adhesive layer 10 may be in a B-stage state, i.e., a semi-cured state, before the wiring layer is formed by the wiring forming member 1. 【0017】 [Composition of Conductive Particles] Conductive particles 12 are conductive, substantially spherical particles, and are composed of metal particles made of metals such as Au, Ag, Ni, Cu, or solder, or conductive carbon particles made of conductive carbon. Conductive particles 12 may also be coated conductive particles comprising a core containing non-conductive glass, ceramic, or plastic (such as polystyrene), and a coating layer containing the above-mentioned metal or conductive carbon that covers the core. Among these, conductive particles 12 may also be coated conductive particles comprising a core containing metal particles formed of a heat-meltable metal, or plastic, and a coating layer containing metal or conductive carbon that covers the core. Conductive particles 12 may also be copper particles from the viewpoint of making it difficult for short circuits to occur in the circuit. 【0018】 In one embodiment, the conductive particles 12 include a core made of polymer particles (plastic particles) such as polystyrene, and a metal layer covering the core. The polymer particles may have substantially their entire surface covered by the metal layer, or a portion of the surface of the polymer particles may be exposed without being covered by the metal layer, to the extent that their function as a connecting material is maintained. The polymer particles may include, for example, polymer particles containing at least one monomer selected from styrene and divinylbenzene as monomer units. 【0019】The metal layer may be formed from various metals such as Ni, Ni / Au, Ni / Pd, Cu, NiB, Ag, Ru, etc. The metal layer may be an alloy layer made of an alloy of Ni and Au, an alloy of Ni and Pd, etc. The metal layer may be a multilayer structure consisting of multiple metal layers. For example, the metal layer may consist of a Ni layer and an Au layer. The metal layer may be made by plating, vapor deposition, sputtering, soldering, etc. The metal layer may be a thin film (for example, a thin film formed by plating, vapor deposition, sputtering, etc.). 【0020】 The conductive particles 12 may have an insulating layer. Specifically, for example, in the conductive particles of the above embodiment, which include a core (e.g., polymer particles) and a coating layer such as a metal layer covering the core, an insulating layer may be provided on the outside of the coating layer to further cover the coating layer. The insulating layer may be the outermost layer located on the outermost surface of the conductive particles. The insulating layer may be a layer formed from an insulating material such as silica or acrylic resin. 【0021】 The average particle size Dp of the conductive particles 12 may be 1 μm or more, 2 μm or more, 5 μm or more, or 8 μm or more, from the viewpoint of excellent dispersibility and conductivity. The average particle size Dp of the conductive particles may be 50 μm or less, 30 μm or less, 20 μm or less, or 15 μm or less, from the viewpoint of excellent dispersibility and conductivity. From the above viewpoint, the average particle size Dp of the conductive particles may be 1 to 50 μm, 5 to 30 μm, 2 to 20 μm, 5 to 20 μm, or 8 to 15 μm. 【0022】The maximum particle size of the conductive particles 12 may be smaller than the minimum distance between electrodes in the wiring pattern (the shortest distance between adjacent electrodes). From the viewpoint of excellent dispersibility and conductivity, the maximum particle size of the conductive particles 12 may be 1 μm or more, 2 μm or more, 5 μm or more, or 8 μm or more. From the viewpoint of excellent dispersibility and conductivity, the maximum particle size of the conductive particles may be 50 μm or less, 30 μm or less, 20 μm or less, or 15 μm or less. From the above viewpoint, the maximum particle size of the conductive particles may be 1 to 50 μm, 2 to 30 μm, 5 to 20 μm, or 8 to 15 μm. 【0023】 In this specification, the particle size of any 300 particles (pcs) is measured by observation using a scanning electron microscope (SEM). The average value of the obtained particle sizes is defined as the average particle size Dp, and the largest value obtained is defined as the maximum particle size. If the particle has protrusions or other non-spherical shapes, the particle size is defined as the diameter of the circle circumscribing the particle in the SEM image. 【0024】The content of conductive particles 12 is determined according to the fineness of the electrodes to be connected. For example, there are no particular restrictions on the amount of conductive particles 12, but it may be 0.1 volume% or more, 0.2 volume% or more, 0.5 volume% or more, 0.8 volume% or more, 1 volume% or more, 1.2 volume% or more, or 1.5 volume% or more, based on the total volume of the adhesive film (adhesive layer). When the above amount is within these ranges, resistance unevenness and low conductivity tend to be suppressed. The amount of conductive particles 12 may be 30 volume% or less, 15 volume% or less, 10 volume% or less, or 5 volume% or less, based on the total volume of the adhesive film (adhesive layer). From the above viewpoint, the amount of conductive particles 12 may be 0.1 to 30 volume%, 0.5 to 15 volume%, 1 to 10 volume%, or 1.5 to 5 volume%. When the above-mentioned proportions are within these ranges, short circuits tend to be less likely to occur. Note that "volume %" is determined based on the volume of each component before curing at 23°C, but the volume of each component can be converted from weight to volume using specific gravity. Alternatively, instead of dissolving or swelling the component in a graduated cylinder, the component can be added to a suitable solvent (water, alcohol, etc.) that thoroughly wets the component, and the increased volume can be used to determine the volume of that component. 【0025】 From the viewpoint of reducing the connection resistance between wires, the adhesive layer 10 may contain copper particles as conductive particles 12. In this case, the area of ​​the wiring layer to be formed will increase (for example, 2500 mm²). ２ As described above, unevenness in the springback of copper particles due to pressure unevenness can easily occur, leading to a decrease in connectivity under high-temperature conditions. However, by having the thermal expansion coefficient of the cured material described later be within a specific range, it is possible to form a wiring layer with excellent connectivity under high-temperature conditions while reducing connection resistance. 【0026】Copper particles can be made containing one or more of Cu and alloys of Cu with other metals. Examples of alloys of Cu with other metals include silver, zinc, nickel, gold, lead, tin, aluminum, manganese, beryllium, tungsten, and iron. From the viewpoint of reducing connection resistance between wires and reducing manufacturing costs, the Cu content in the copper particles may be 50% by mass or more, 70% by mass or more, or 100% by mass. 【0027】 The shape of the copper particles may be spherical, nearly spherical, flake-like, columnar, rod-like, needle-like, plate-like, or fibrous. 【0028】 The average particle size Dp of copper particles may be 0.5 μm or more, 1 μm or more, or 3 μm or more, from the viewpoint of lowering the connection resistance between wirings and increasing the resolution of wiring. The average particle size Dp of conductive particles may be 300 μm or less, 100 μm or less, or 50 μm or less, from the viewpoint of improving insulation between adjacent wirings. From the above viewpoint, the average particle size Dp of conductive particles may be 0.5 to 300 μm, 1 to 100 μm, or 3 to 50 μm. 【0029】 The maximum particle size of the copper particles may be smaller than the minimum distance between electrodes in the wiring pattern (the shortest distance between adjacent electrodes). From the viewpoint of lowering the connection resistance between wirings, the maximum particle size of the copper particles may be 0.5 μm or more, 1 μm or more, or 3 μm or more. From the viewpoint of improving insulation between adjacent wirings, the maximum particle size of the conductive particles may be 300 μm or less, 100 μm or less, or 50 μm or less. From the above viewpoint, the maximum particle size of the conductive particles may be 0.5 to 300 μm, 1 to 100 μm, or 3 to 50 μm. 【0030】From the viewpoint of reducing connection resistance, the copper particle content can be 6 volume% or less based on the total volume of the adhesive film (adhesive layer). When the copper particle content is 6 volume% or less, the copper particles can be sufficiently flattened, thereby ensuring a sufficient connection area between the electrodes or wiring provided on the substrate and the metal layer. Generally, it is thought that connection resistance decreases as the content of conductive particles increases, but in the case of copper particles, it has become difficult to flatten them when the content exceeds 6 volume%, making it difficult to reduce connection resistance. This finding was revealed through the inventors' studies and can be considered unexpected. From the viewpoint of reducing connection resistance, improving insulation between adjacent wirings, and reducing manufacturing costs, the copper particle content may be 0.1 to 6 volume%, or 0.5 to 3 volume%. 【0031】 [Composition of Adhesive Layer / Adhesive Components] The adhesive components 14 constituting the adhesive layer 10 may be a thermosetting resin composition. Components included in the thermosetting resin composition include a thermosetting resin, a curing agent, and a curing accelerator. 【0032】 The adhesive components contain at least an epoxy resin (hereinafter also referred to as "epoxy resin X") with an epoxy equivalent of 150 g / eq or less, and a phenolic resin. The epoxy equivalent is determined by the method standardized in JIS standard (K7236:2001). 【0033】 Examples of epoxy resin X include pentaerythritol glycidyl ether and trimethylolpropane triglycidyl ether. From the viewpoint of improving heat resistance and film toughness, epoxy resin X may contain at least one selected from the group consisting of pentaerythritol glycidyl ether and trimethylolpropane triglycidyl ether, and may also be pentaerythritol glycidyl ether. 【0034】The epoxy equivalent of epoxy resin X may be 50 g / eq or more, 70 g / eq or more, 80 g / eq or more, or 90 g / eq or more, from the viewpoint of improving heat resistance and film toughness, and from the same viewpoint, it may be 140 g / eq or less, 135 g / eq or less, 130 g / eq or less, 120 g / eq or less, 110 g / eq or less, or 100 g / eq or less. From the above viewpoint, the epoxy equivalent of epoxy resin X may be 50 to 150 g / eq, 70 to 140 g / eq, 80 to 135 g / eq, or 90 to 130 g / eq. 【0035】 From the viewpoint of improving heat resistance and film toughness, the epoxy resin X may have three or more epoxy groups, or four or more. 【0036】 The molecular weight of epoxy resin X may be 200 or more, 250 or more, or 300 or more, from the viewpoint of improving heat resistance and film toughness, and from the same viewpoint, it may be 1000 or less, 800 or less, 600 or less, 500 or less, or 400 or less. From the above viewpoint, the molecular weight of epoxy resin X may be 200 to 1000, 250 to 600, or 300 to 400. 【0037】 Thermosetting resins are resins that harden when heated. Examples of thermosetting resins include epoxy resins other than epoxy resin X (hereinafter also referred to as "epoxy resin Y"), polyimide resins, triazine resins such as melamine resins, phenolic resins, and modified versions of these resins. Among these, epoxy resins other than epoxy resin X may be used from the viewpoint of sufficiently suppressing the occurrence of bubbles or delamination during wiring formation and from the viewpoint of improving heat resistance and film toughness. 【0038】The epoxy resin Y can be any compound having two or more epoxy groups in its molecule, and examples include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, biphenyl type epoxy resin, biphenyl novolac type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolac type epoxy resin, bisphenol F novolac type epoxy resin, naphthalene type polyfunctional epoxy resin, dicyclopentadiene type epoxy resin, alicyclic epoxy resin, aliphatic chain epoxy resin, glycidyl ester type epoxy resin, isocyanurate type epoxy resin, hydantoin type epoxy resin, glycidyl ether compounds of polyfunctional phenols, glycidyl ether compounds of difunctional alcohols, and hydrogenated versions thereof. Of these, from the viewpoint of ease of handling and availability, novolac type epoxy resins such as biphenyl novolac type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolac type epoxy resin, or bisphenol F novolac type epoxy resin may be used. Epoxy resin Y may be used alone or in combination of two or more types. 【0039】 From the viewpoint of ensuring adhesive strength and heat resistance, the number of epoxy groups in the epoxy resin Y of the adhesive component may be three or more. 【0040】 From the viewpoint of ensuring adhesive strength and heat resistance, and good reactivity, the epoxy resin Y may have an epoxy equivalent of more than 150 g / eq and 1000 g / eq or less, more than 150 g / eq and 900 g / eq or less, or more than 150 g / eq and 800 g / eq or less. 【0041】From the viewpoint of improving heat resistance and film toughness, the content of epoxy resin X in the adhesive component may be 5% by mass or more, 10% by mass or more, 15% by mass or more, based on the total amount of adhesive component (total amount of solids other than conductive particles and fillers in the adhesive layer), and from the same viewpoint, it may be 50% by mass or less, 40% by mass or less, 30% by mass or less, 25% by mass or less, or 20% by mass or less. From the above viewpoint, the content of epoxy resin X in the adhesive component may be 5 to 50% by mass, 5 to 30% by mass, 5 to 20% by mass, 10 to 50% by mass, 10 to 30% by mass, or 10 to 20% by mass, based on the total amount of adhesive component (total amount of solids other than conductive particles and fillers in the adhesive layer). 【0042】 From the viewpoint of improving heat resistance and film toughness, the content of epoxy resin X in the adhesive component may be 20% by mass or more, 30% by mass or more, 35% by mass or more, or 40% by mass or more, based on the total mass of the epoxy resin. Similarly, from the viewpoint of improving heat resistance and film toughness, it may be 80% by mass or less, 70% by mass or less, 60% by mass or less, or 50% by mass or less. From the above viewpoint, the content of epoxy resin X in the adhesive component may be 20 to 80% by mass, 30 to 70% by mass, or 35 to 60% by mass, based on the total mass of the epoxy resin. 【0043】From the perspective of improving heat resistance and film toughness, the content of epoxy resin X in the adhesive component may be 20 parts by mass or more, 30 parts by mass or more, 40 parts by mass or more with respect to 100 parts by mass of the phenolic resin. From the same perspective, it may be 150 parts by mass or less, 125 parts by mass or less, 100 parts by mass or less, 80 parts by mass or less, 60 parts by mass or less. From the above perspective, the content of epoxy resin X in the adhesive component may be 20 to 150 parts by mass, 20 to 100 parts by mass, 30 to 80 parts by mass, or 30 to 60 parts by mass with respect to 100 parts by mass of the phenolic resin. 【0044】 The content of the epoxy resin (epoxy resin X and epoxy resin Y) in the adhesive component may be 5 to 95% by mass, 10 to 90% by mass, 15 to 85% by mass, or 40 to 60% by mass based on the total amount of the adhesive component (the total solid content other than the conductive particles and the filler in the adhesive layer). 【0045】 The phenolic resin functions as a curing agent for the epoxy resin. Examples of the phenolic resin include novolak-type phenolic resins such as phenol novolak, cresol novolak, bisphenol A novolak, bisphenol F novolak, and catechol novolak, and those in which the aromatic rings thereof are substituted with alkyl groups. From the perspective of improving heat resistance and film toughness, the phenolic resin may be a novolak-type phenolic resin. The phenolic resin may be used alone or in combination of two or more. 【0046】From the perspective of ensuring adhesive strength and heat resistance, the adhesive component may contain, as a phenolic resin, a compound having three or more phenolic groups or cresol groups in one molecule. Such compounds may include, from the perspective of handling properties and availability, phenol novolak type phenolic resin, cresol novolak type phenolic resin, bisphenol A novolak type phenolic resin, or bisphenol F novolak type phenolic resin, etc. From the perspective of improving heat resistance and film toughness, a cresol novolak type phenolic resin may also be used. 【0047】 From the perspective of suppressing the generation of bubbles or peeling during wiring formation and making it difficult to generate resistance unevenness, the hydroxyl equivalent of the phenolic resin may be 300 g / eq or less, 250 g / eq or less, 200 g / eq or less, or 150 g / eq or less. From the perspective of ease of handling and good reactivity, it may also be 50 g / eq or more, 80 g / eq or more, or 100 g / eq or more. From the above perspectives, the hydroxyl equivalent of the phenolic resin may be 50 - 300 g / eq, 80 - 200 g / eq, or 100 - 150 g / eq. 【0048】 Note that the hydroxyl equivalent of the phenolic resin is determined by the following measurement method. <Measurement method of hydroxyl equivalent> Precisely weigh 1 g of the sample into a round-bottom flask, and then accurately weigh 5 mL of acetic anhydride and pyridine test solution. Next, attach an air condenser to the flask and heat it at 100°C for 1 hour. After cooling the flask, add 1 mL of water and heat the flask at 100°C for 10 minutes again. After re-cooling the flask, wash the air condenser and the neck of the flask with 5 mL of neutral methanol, and add 1 mL of phenolphthalein reagent. For the solution thus obtained, titrate it using a 0.1 mol / L potassium hydroxide - ethanol solution to obtain the hydroxyl value. Calculate the hydroxyl equivalent (g / eq) converted from the obtained hydroxyl value to the mass per 1 mol (1 eq) of hydroxyl groups. 【0049】The amount of phenolic resin in the adhesive component can be set so that the number of hydroxyl groups in the phenolic resin is 0.5 to 2 per epoxy group of the epoxy resin. 【0050】 From the viewpoint of ensuring adhesive strength and heat resistance, the phenol resin content in the adhesive component may be 20% by mass or more, 30% by mass or more, or 35% by mass or more, based on the total amount of adhesive component (total amount of solids other than conductive particles and fillers in the adhesive layer). From the viewpoint of improving heat resistance and film toughness, it may be 60% by mass or less, 50% by mass or less, or 45% by mass or less. From the above viewpoint, the phenol resin content in the adhesive component may be 20 to 60% by mass, 30 to 50% by mass or 35 to 45% by mass, based on the total amount of adhesive component (total amount of solids other than conductive particles and fillers in the adhesive layer). 【0051】 The adhesive component containing epoxy resin and phenolic resin may further contain thermosetting resins other than epoxy resin, and may further contain curing agents other than phenolic resin. Examples of thermosetting resins other than epoxy resin include polyimide resins, triazine resins such as melamine resins, and modified versions of these resins. Examples of curing agents other than phenolic resin include amines, amides, acid anhydrides, acids, and imidazoles. 【0052】 Furthermore, in the wiring forming member of this embodiment, the adhesive component may further contain a maleimide compound from the viewpoint of sufficiently suppressing the occurrence of air bubbles or peeling during wiring formation. 【0053】 In this case, from the viewpoint of sufficiently suppressing the occurrence of air bubbles or peeling during wiring formation, the adhesive component may contain epoxy resin as a thermosetting resin. The epoxy resin content in the adhesive component in this case may be 5 to 95% by mass, 10 to 90% by mass, 15 to 85% by mass, or 15 to 40% by mass, based on the total amount of the adhesive component (total amount of solids other than conductive particles and fillers in the adhesive layer). 【0054】Examples of curing accelerators include imidazole compounds, organophosphorus compounds, tertiary amines, and quaternary ammonium salts. A single curing accelerator may be used, or two or more may be used in combination. The adhesive component may contain an imidazole compound as a curing accelerator, from the viewpoint of allowing arbitrary adjustment of the temperature and time during use (e.g., heating temperature and time during heat bonding). 【0055】 The amount of curing accelerator in the adhesive component may be 0.001 to 10% by mass, 0.01 to 1% by mass, or 0.05 to 0.5% by mass, based on the total amount of adhesive component (total amount of solids other than conductive particles and fillers in the adhesive layer). 【0056】 The adhesive component 14 may contain other components besides the thermosetting component described above. These other components may include fillers, antioxidants, film-forming agents, softeners, anti-aging agents, colorants, flame retardants, thixotropic agents, coupling agents, and the like. 【0057】 Examples of fillers include inorganic fillers and organic fillers. Examples of inorganic fillers include alumina, silica, titanium dioxide, clay, calcium carbonate, aluminum carbonate, magnesium silicate, aluminum silicate, mica, glass short fibers, aluminum borate, silicon carbide, etc. Examples of organic fillers include silicone particles, methacrylate / butadiene / styrene particles, acrylic / silicone particles, polyamide particles, polyimide particles, etc. Fillers may be used individually or in combination of two or more types. 【0058】 The adhesive component may contain silica particles as a filler, from the viewpoint of improving heat resistance, improving mechanical properties, and adjusting fluidity during use (for example, during heat bonding). 【0059】 The maximum diameter of the filler material may be less than the particle size of the conductive particles 12, and may be between 0.001 and 10 μm. 【0060】The filler content may be 5 to 60 parts by volume, 7 to 40 parts by volume, or 10 to 30 parts by volume per 100 parts by volume of adhesive component. When the filler content is within the above ranges, good connection reliability tends to be obtained. 【0061】 Examples of antioxidants include quinone derivatives such as benzoquinone and hydroquinone, phenol derivatives (hindered phenol derivatives) such as 4-methoxyphenol and 4-t-butylcatechol, aminooxyl derivatives such as 2,2,6,6-tetramethylpiperidine-1-oxyl and 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl, and hindered amine derivatives such as tetramethylpiperidyl methacrylate. 【0062】 The antioxidant content may be 0.01% to 5% by mass or 0.1% to 3% by mass, based on the total amount of adhesive components (total amount of solids other than conductive particles and fillers in the adhesive layer). 【0063】 Suitable film-forming materials include thermoplastic resins such as phenoxy resin, polyvinyl formal resin, polystyrene resin, polyvinyl butyral resin, polyester resin, polyamide resin, xylene resin, polyurethane resin, polyacrylic resin, and polyester urethane resin. Furthermore, these polymers may contain siloxane bonds or fluorine substituents. These resins can be used individually or in mixtures of two or more. Among the above resins, phenoxy resin may be used from the viewpoint of adhesive strength, compatibility, heat resistance, and mechanical strength. 【0064】 The larger the molecular weight of the thermoplastic resin, the easier it is to obtain film-forming properties, and the wider the range of melt viscosity that affects the fluidity of the film. The molecular weight of the thermoplastic resin may be 5,000 to 150,000 or 10,000 to 80,000 in weight-average molecular weight. Good film-forming properties are easily obtained by setting the weight-average molecular weight to 5,000 or higher, and good compatibility with other components is easily obtained by setting it to 150,000 or lower. 【0065】In this disclosure, weight-average molecular weight refers to the value measured using a calibration curve with standard polystyrene from a gel permeation chromatograph (GPC) according to the following conditions: (Measurement conditions) Apparatus: GPC-8020 manufactured by Tosoh Corporation Detector: RI-8020 manufactured by Tosoh Corporation Column: Gelpack GLA160S + GLA150S manufactured by Resonaq Corporation Sample concentration: 120 mg / 3 mL Solvent: Tetrahydrofuran Injection volume: 60 μL Pressure: 2.94 × 10⁻⁶ ６ Pa (30kgf / cm ２ ) Flow rate: 1.00mL / min 【0066】 Furthermore, the content of the film-forming material may be 0.5 to 75% by mass, 1 to 50% by mass, 5 to 30% by mass, or 10 to 20% by mass, based on the total amount of adhesive components (total amount of solids other than conductive particles and fillers in the adhesive layer). 【0067】 Adhesive component 14 may substantially contain highly reactive radical polymerizable compounds such as acrylic compounds, methacrylic compounds, styrene compounds, and vinyl compounds, from the viewpoint of improving storage stability and connection reliability. "Substantially contained" means that the content, based on the total amount of adhesive components (total amount of solids other than conductive particles and fillers in the adhesive layer), is 1% by mass or less. The content of the above compounds in the adhesive components may be 0.5% by mass or less, or 0% by mass, based on the total amount of adhesive components (total amount of solids other than conductive particles and fillers in the adhesive layer). 【0068】 The thickness of the adhesive layer may be 1 to 70 μm, 2 to 60 μm, or 3 to 50 μm. The thickness of the adhesive layer can be measured by observing the cross-section of the adhesive with a scanning electron microscope (SEM). 【0069】[Metal Layer Composition] The surface roughness Rz of one surface and the opposite surface of the metal layer 20 may be the same, or they may be different. The metal layer 20 has a thickness of, for example, 5 μm to 200 μm. The thickness of the metal layer referred to here includes the surface roughness Rz. The metal layer 20 may be, for example, copper foil, aluminum foil, nickel foil, stainless steel, titanium, or platinum. 【0070】 An adhesive layer 10 is disposed on the first surface 20a of the metal layer 20. The surface roughness Rz of the first surface 20a of the metal layer 20 may be 0.3 μm or more, 0.5 μm or more, or 1.0 μm or more. Also, the surface roughness Rz of the first surface 20a of the metal layer 20 may be 50 μm or less, 40 μm or less, 30 μm or less, 20 μm or less, less than 20 μm, 17 μm or less, 10 μm or less, 8.0 μm or less, 5.0 μm or less, or 3.0 μm or less. For example, the surface roughness Rz of the first surface 20a of the metal layer 20 may be 0.3 μm or more and 20 μm or less, 0.3 μm or more and less than 20 μm, and more specifically, 0.5 μm or more and 10 μm or less. The surface roughness Rz of the second surface 20b of the metal layer 20 may be, for example, 20 μm or more, and may be rougher than the surface roughness Rz of the first surface 20a, or may be the same as the surface roughness of the first surface 20a, or may not be rougher than the surface roughness Rz of the first surface 20a. If the surface roughness Rz of the first surface 20a of the metal layer 20 is too smooth (for example, the surface roughness Rz is 0.2 μm), the adhesion between the metal layer 20 and the adhesive layer 10 may not be maintained over a long period of time and may peel off. For this reason, the surface roughness Rz of the first surface 20a of the metal layer 20 may be 0.3 μm or more. However, by employing a material or connection configuration that can ensure adhesion, the surface roughness Rz of the first surface 20a of the metal layer 20 may be less than 0.3 μm. 【0071】Surface roughness Rz refers to the ten-point average roughness Rzjis measured according to the method specified in the JIS standard (JIS B 0601-2001), and is a value measured using a commercially available surface roughness shape measuring instrument. For example, it can be measured using a nanosearch microscope (Shimadzu Corporation's "SFT-3500"). 【0072】 Here, the relationship between the average particle size Dp of the conductive particles 12 and the surface roughness Rz of the first surface 20a of the metal layer 20 will be explained below. In this embodiment, the ratio of the surface roughness Rz of the first surface 20a of the metal layer 20 to the average particle size Dp of the conductive particles 12, known as "surface roughness / average particle size," may be 0.03 or more, 0.04 or more, 0.05 or more, 0.06 or more, 0.1 or more, 0.2 or more, 0.3 or more, 0.5 or more, or 1 or more. Also, the ratio of the surface roughness Rz of the first surface 20a of the metal layer 20 to the average particle size Dp of the conductive particles 12, known as "surface roughness / average particle size," may be 3 or less, 2 or less, 1.7 or less, or 1.5 or less. The "surface roughness / average particle size," which is the ratio of the surface roughness Rz of the first surface 20a of the metal layer 20 to the average particle size Dp of the conductive particles 12, may be, for example, 0.05 or more and 3 or less, and more specifically, 0.06 or more and 2 or less. In this embodiment, the surface roughness Rz of the first surface 20a of the metal layer 20 and the average particle size Dp of the conductive particles 12 may be controlled so that the "surface roughness / average particle size," which is the ratio of the surface roughness Rz of the first surface 20a of the metal layer 20 to the average particle size Dp of the conductive particles 12, is in the range of 0.05 to 3. 【0073】 This disclosure also relates to a method for forming a wiring layer using a wiring-forming member. The method for forming a wiring layer using the wiring-forming member 1 described above will be explained with reference to Figure 2. Figures 2(a) to 2(d) show the method for forming a wiring layer using the wiring-forming member shown in Figure 1. 【0074】First, prepare the wiring forming member 1 as shown in Figure 2(a). Next, prepare the base material 30 on which the wiring 32 is formed. Then, position the wiring forming member 1 so that the adhesive layer 10 side of the wiring forming member 1 faces the base material 30. After that, as shown in Figure 2(b), laminate is applied to cover the wiring 32 and the wiring forming member 1 is attached to the base material 30. 【0075】 Next, as shown in Figure 2(c), the wiring forming member 1 is subjected to predetermined heating and pressurization to bond it to the base material 30. At this time, if the first surface 20a of the metal layer 20 of the wiring forming member 1 is flat, the conductive particles 12, which need to be made conductive, can be more reliably deformed into flattened conductive particles 12a. Then, in the bonded wiring forming member 1a, the flattened conductive particles 12a (which destroy the insulating layer and expose the conductive portion) are arranged on the wiring 32, ensuring reliable electrical conductivity between the metal layer 20 and the wiring 32. At this time, the adhesive layer 10 is also crushed, becoming a thinner adhesive layer 10A. 【0076】 Next, as shown in Figure 2(d), a predetermined patterning process (e.g., etching) is performed on the metal layer 20 to process it into wiring 20c (another wiring) with a predetermined wiring pattern. At this time, the second surface 20b of the metal layer 20 may be treated to make it a smooth surface. The processes described above in Figure 2(a) to (d) may be repeated a predetermined number of times to form a wiring layer. 【0077】 In other words, the method for forming a wiring layer using a wiring-forming member comprises the steps of: preparing a wiring-forming member; preparing a substrate on which wiring is formed; arranging the wiring-forming member on the surface of the substrate on which wiring is formed so as to cover the wiring, with the adhesive layer side facing the substrate; heat-pressing the wiring-forming member to the substrate; and performing a patterning treatment on the metal layer. 【0078】As a result, the wiring-forming member 1b is formed. This wiring-forming member 1b comprises a base material 30 having wiring 32, and a cured product of the adhesive component 14 of the wiring-forming member 1 (the adhesive layer of the heating-pressed wiring-forming member) placed on the base material 30 so as to cover the wiring 32. In this wiring-forming member 1b, the wiring 32 and the metal layer 20 of the wiring-forming member 1 or the wiring 20c formed from the metal layer 20 (for example, by etching) are electrically connected by conductive particles 12a. Note that if the processes in Figures 2(a) to (d) are repeated a predetermined number of times, the wiring-forming member 1b may have a configuration having multiple wiring layers (layers connecting the aforementioned wirings). 【0079】 Thus, the method for forming a wiring layer using the wiring-forming member 1 according to this embodiment simplifies the process of forming the wiring layer connecting the wirings compared to conventional processes such as laser processing and filled plating. Furthermore, the formed wiring layer can be easily made thinner. 【0080】 Furthermore, according to the method for forming a wiring layer using the wiring forming member 1 of this embodiment, when the ratio [Dp / T] of the average particle size Dp of the conductive particles 12 to the thickness T of the adhesive layer 10 is 0.56 to 1.2, a wiring layer with suppressed resistance unevenness can be formed. 【0081】Although embodiments of the present disclosure have been described in detail above, the present disclosure is not limited to the above embodiments and can be applied to various embodiments. For example, in the above embodiment, as shown in Figure 3(a), the conductive particles 12 were randomly or evenly dispersed within the adhesive layer 10 in the wiring forming member 1. However, as shown in Figure 3(b), the conductive particles 12 may be arranged (unevenly distributed) on the metal layer 20 side. In this case, in the adhesive layer 10, the conductive particles 12 are not exposed on the side opposite to the metal layer 20, and the thickness of the adhesive layer 10 between the conductive particles 12 and the metal layer 20 may be greater than 0 μm or 0.1 μm and less than or equal to 1 μm. In this case, since the conductive particles 12 are arranged on the metal layer 20 side, the metal layer 20 can more reliably flatten the conductive particles 12 into a flat shape in the wiring layer 1d. Furthermore, by unevenly distributing the conductive particles 12 on the metal layer 20 side in this way, the capture rate of the conductive particles 12 to the wiring (electrodes), etc., can be improved. In other words, conductivity can be made more stable. The distance between the conductive particles 12 and the metal layer 20 (the thickness of the adhesive layer 10 between them) refers to the shortest distance from the surface of the metal layer 20 in contact with the adhesive layer 10 to the surface of the conductive particles 12, and is, for example, the average value at any 30 points. This distance is measured by sandwiching the wiring forming member between two pieces of glass (thickness: approximately 1 mm), casting a resin composition consisting of 100 g of bisphenol A type epoxy resin (product name: JER811, manufactured by Mitsubishi Chemical Corporation) and 10 g of a hardener (product name: Epomount hardener, manufactured by Refinetech Co., Ltd.), performing cross-sectional polishing using a polishing machine, and measuring it using a scanning electron microscope (SEM, product name: SE-8020, manufactured by Hitachi High-Tech Science Corporation). 【0082】Furthermore, as shown in Figure 3(c), the adhesive layer 10d may be formed by dividing it into a first adhesive layer 10e and a second adhesive layer 10f. The adhesive components constituting the first adhesive layer 10e and the second adhesive layer 10f may be the same as the adhesive components constituting the adhesive layer 10 described above, but the difference is that conductive particles 12 are not dispersed in the second adhesive layer 10f, i.e., are not included. In this case as well, if the ratio [Dp / T] of the average particle size Dp of the conductive particles 12 to the thickness T of the adhesive layer 10 is 0.56 to 1.2, a wiring layer with suppressed resistance unevenness can be formed. In the wiring forming member 1e according to this modified example, conductive particles 12 are dispersed in the first adhesive layer 10e, i.e., included. In this case, similar to the modified example shown in Figure 3(b), the conductive particles 12 are arranged on the metal layer 20 side, so that in the wiring layer 1f, the conductive particles 12 can be more reliably flattened into a flat shape by the metal layer 20. Furthermore, by unevenly distributing the conductive particles 12 towards the metal layer 20 in this manner, the capture rate of the conductive particles 12 by the wiring (electrodes), etc., can be improved. In other words, the conductivity can be made more stable. 【0083】 Furthermore, the wiring forming members 1, 1c, and 1e may further include a release film. The release film may be bonded to the side of the adhesive layers 10, 10c, and 10d opposite to the side to which the metal layer 20 is bonded, or to the side of the metal layer 20 opposite to the side to which the adhesive layers 10, 10c, and 10d are bonded, or to both sides. In addition, the first surface 20a of the metal layer 20 may be bonded to the adhesive layers 10, 10c, and 10d. In this case, the wiring forming members become easier to handle, and the work efficiency when forming wiring layers using the wiring forming members can be improved. 【0084】Furthermore, although the above description used the example of a wiring-forming member being a member formed by bonding an adhesive layer 10 and a metal layer 20, the wiring-forming member in this embodiment may be a set in which the adhesive layer 10 and the metal layer 20 are provided separately, and the adhesive layer 10 can be bonded to the first surface 20a of the metal layer 20 when in use. In this case, since the adhesive layer 10 and the metal layer 20 can be prepared separately (as a set of wiring-forming members), it becomes possible to select a wiring-forming member with a more optimal material configuration, thereby improving the degree of freedom in the work when creating a wiring layer using the wiring-forming member. 【0085】 The adhesive film with a metal layer of this embodiment may have an adhesive layer comprising a first adhesive layer containing copper particles and an adhesive component, and a second adhesive layer containing an adhesive component. Such an adhesive film with a metal layer can also be used to form wiring. The details of the adhesive film with a metal layer having the above configuration will be described below, with an example of its use as a wiring forming member. 【0086】 Figure 4 is a cross-sectional view showing a wiring-forming member according to another embodiment of the present disclosure. The wiring-forming member 2 shown in Figure 4 comprises an adhesive layer 10 containing conductive particles 12 and a metal layer 20. The adhesive layer 10 comprises a first adhesive layer 15 containing conductive particles 12 and an adhesive component 14, and a second adhesive layer 16 containing an adhesive component 17. 【0087】 The first adhesive layer 15 contains conductive particles 12 and an insulating adhesive component 14 in which the conductive particles 12 are dispersed. The adhesive component 14 is the same as described above. 【0088】 The second adhesive layer 16 contains an insulating adhesive component 17. The insulating adhesive component 17 in the second adhesive layer 16 may be the same as or different from the adhesive component 14. The adhesive component 17 of the second adhesive layer 16 is defined as solid components other than conductive particles. Before the wiring layer is formed by the wiring forming member 2, the second adhesive layer 16 may be in a B-stage state, i.e., a semi-cured state. 【0089】In this embodiment, the adhesive layer 10 is configured such that the reactivity of the first adhesive layer 15 and the second adhesive layer 16 is adjusted, and the average particle size of the conductive particles 12, as well as the thicknesses of the first adhesive layer 15 and the second adhesive layer 16, are adjusted so that the ratio [Dp / T] of the average particle size Dp of the conductive particles 12 to the thickness T of the adhesive layer 10 falls within the range described above. 【0090】 The thickness d1 of the first adhesive layer 15 may be 0.56 to 1.2 times, 0.56 to 1.0 times, or 0.56 to 0.80 times the average particle size Dp of the conductive particles 12. 【0091】 The thickness of the first adhesive layer 15 may be 1 to 70 μm, 1 to 60 μm, or 1 to 50 μm. 【0092】 The thickness of the second adhesive layer 16 may be 0 to 50 μm, 0 to 40 μm, or 0 to 30 μm. 【0093】 Next, a method for forming a wiring layer using the wiring forming member 2 described above will be explained with reference to Figure 5. Figures 5(a) to 5(d) show a method for forming a wiring layer using the wiring forming member shown in Figure 4. 【0094】 First, prepare the wiring-forming member 2 as shown in Figure 5(a). Next, prepare the base material 30 on which the wiring 32 is formed. Then, position the wiring-forming member 2 so that the adhesive layer 10 side of the wiring-forming member 2 faces the base material 30. After that, as shown in Figure 5(b), laminate is applied to cover the wiring 32 and the wiring-forming member 2 is attached to the base material 30. 【0095】Next, as shown in Figure 5(c), the wiring forming member 2 is subjected to predetermined heating and pressurization to bond it to the base material 30. At this time, if the first surface 20a of the metal layer 20 of the wiring forming member 2 is flat, the conductive particles 12 that need to be made conductive can be more reliably deformed into flattened conductive particles 12a. Then, in the bonded wiring forming member 2a, the flattened conductive particles 12a (which thus destroy the insulating layer and expose the conductive portion) are arranged on the wiring 32, and good electrical conductivity is achieved between the metal layer 20 and the wiring 32. At this time, the adhesive layer 10 is also crushed to become a thinner adhesive layer 10B. Furthermore, since the adhesive layer 10 comprises a first adhesive layer 15 in which conductive particles are contained in the adhesive component and a second adhesive layer 16, good insulation reliability in the thickness direction of areas where electrical connection is not desired is achieved. 【0096】 Next, as shown in Figure 5(d), a predetermined patterning process (e.g., etching) is performed on the metal layer 20 to process it into wiring 20c (another wiring) with a predetermined wiring pattern. At this time, the second surface 20b of the metal layer 20 may be treated to make it a smooth surface. The processes described above in Figures 5(a) to (d) may be repeated a predetermined number of times to form the wiring layer. 【0097】 In other words, the method for forming a wiring layer using a wiring-forming member comprises the steps of: preparing a wiring-forming member; preparing a substrate on which wiring is formed; arranging the wiring-forming member on the surface of the substrate on which wiring is formed so as to cover the wiring, with the adhesive layer side facing the substrate; heat-pressing the wiring-forming member to the substrate; and performing a patterning treatment on the metal layer. 【0098】As a result, the wiring-forming member 2b is formed. This wiring-forming member 2b comprises a base material 30 having wiring 32, and a cured product of the first adhesive layer 15 and the second adhesive layer 16 of the wiring-forming member 2, which is placed on the base material 30 so as to cover the wiring 32 (the adhesive layer of the wiring-forming member that has been heat-pressed). In this wiring-forming member 2b, the wiring 32 and the metal layer 20 of the wiring-forming member 2 or the wiring 20c formed from the metal layer 20 (for example, by etching) are electrically connected by conductive particles 12a. Note that if the processes in Figures 5(a) to (d) are repeated a predetermined number of times, the wiring-forming member 2b may have a configuration having multiple wiring layers (layers connecting the aforementioned wirings). 【0099】 Thus, the method for forming a wiring layer using the wiring-forming member 2 according to this embodiment simplifies the process of forming the wiring layer connecting the wirings compared to conventional processes such as laser processing and filled plating. Furthermore, it becomes possible to easily make the formed wiring layer thinner. 【0100】 Furthermore, according to the method for forming a wiring layer using the wiring forming member 2 of this embodiment, when the ratio [Dp / T] of the average particle size Dp of the conductive particles 12 to the thickness T of the adhesive layer 10 is 0.56 to 1.2, a wiring layer with suppressed resistance unevenness can be formed. 【0101】 Furthermore, according to the method for forming a wiring layer using the wiring forming member 2 of this embodiment, sufficient design freedom for the wiring pattern when forming the wiring layer can be ensured by the following effects: (i) Because the adhesive layer 10 includes the second adhesive layer 16, even if the wiring layer formed by patterning the metal layer 20 has parts that should not be electrically connected in the lamination direction (or the thickness direction of the adhesive layer), it becomes easy to ensure insulation reliability in those parts. (ii) In the wiring layer formed by patterning the metal layer 20 or in separately formed rewiring, the conductive particles 12 are less likely to come into contact with parts other than those that are electrically connected, making it easy to suppress power transmission loss in the wiring caused by contact with conductive particles. 【0102】 The above effects will be explained while referring to the drawings. 【0103】Figures 6(a) and 6(b) are cross-sectional views illustrating an example of a case in which a wiring layer is formed using the wiring forming member 2 according to this embodiment. 【0104】 Figure 6(a) shows the state when a base material 30 having wiring patterns 32a and 32b is prepared, and the wiring forming member 2 is placed on the surface of the base material 30 where the wiring patterns are formed so as to cover the wiring patterns 32a and 32b, with the adhesive layer 10 side facing the base material 30. After this, the wiring forming member 2 is heated and pressed against the base material 30, and the metal layer 20 is patterned, to obtain a wiring forming member as shown in Figure 6(b), in which a wiring pattern 20d that is electrically connected to wiring pattern 32a and a wiring pattern 20e that is not electrically connected to wiring pattern 32b are formed. 【0105】 Here, the adhesive layer 10 of the wiring forming member 2 includes a first adhesive layer 15 containing conductive particles 12 and adhesive components 14, and a second adhesive layer 16 that does not contain conductive particles but contains adhesive components 17. As a result, when pressed together, good conductivity can be ensured between the wiring of the wiring pattern 20d and the wiring pattern 32a via the conductive particles 12, while ensuring a distance between the wiring patterns 20e and 32b that do not want to be electrically connected, thus ensuring insulation reliability in the thickness direction of the adhesive layer. 【0106】 Figures 7(a) and 7(b) are cross-sectional views illustrating another example of a case in which a wiring layer is formed using the wiring forming member 2 according to this embodiment. 【0107】Figure 7(a) shows the state when a substrate 30 having a wiring pattern 32a is prepared, and the wiring forming member 2 is placed on the surface of the substrate 30 where the wiring pattern is formed so as to cover the wiring pattern 32a, with the adhesive layer 10 side facing the substrate 30. After this, the wiring forming member 2 is heated and pressed against the substrate 30, and the metal layer 20 is patterned, to obtain a wiring forming member as shown in Figure 7(b), which has a wiring pattern 20d that is electrically connected to the wiring pattern 32a and a wiring pattern 20f (or a portion of the wiring pattern that is not electrically connected) formed thereon. 【0108】 Here, the adhesive layer 10 of the wiring forming member 2 includes a first adhesive layer 15 containing conductive particles 12 and adhesive component 14, and a second adhesive layer 16 containing adhesive component 17 but not conductive particles. This allows for an adhesive layer 10B to be provided that ensures good conductivity between the wiring of the wiring pattern 20d and the wiring pattern 32a via the conductive particles 12 when pressed together, while preventing contact between the wiring pattern 20f and the conductive particles 12. This suppresses power transmission loss in the wiring caused by contact with conductive particles in the wiring pattern 20f. In particular, in the wiring forming member 2, the metal layer 20, the second adhesive layer 16, and the first adhesive layer 15 are laminated in this order, making it easy to prevent contact between the wiring pattern 20f and the conductive particles 12. 【0109】 In the method shown in Figure 7, the wiring pattern 20f may be formed by the steps of performing a patterning treatment on the metal layer 20 and forming a rewiring. 【0110】 In the first adhesive layer 15 of the wiring forming member 2 shown in Figure 4, the conductive particles 12 are arranged locally, but the conductive particles 12 may be randomly or evenly dispersed within the adhesive component 14. 【0111】 Furthermore, in the first adhesive layer 15 of the wiring forming member 2, the conductive particles 12 may be locally arranged on the side of the second adhesive layer 16, or they may be locally arranged on the opposite side of the second adhesive layer 16 (the side of the second surface 10b of the adhesive layer 10). 【0112】 Furthermore, although the second adhesive layer 16 of the wiring forming member 2 does not contain conductive particles, the second adhesive layer 16 may contain a portion of the particle body of the conductive particles 12 (in other words, it does not have to contain the entire particle body of the conductive particles 12). 【0113】 Furthermore, the adhesive layer 10 of the wiring forming member 2 may consist of two layers, a first adhesive layer 15 and a second adhesive layer 16, or it may consist of three or more layers, including a layer other than the first adhesive layer 15 and the second adhesive layer 16 (for example, a third adhesive layer). The third adhesive layer may have the same composition as the first adhesive layer 15 or the second adhesive layer 16 as described above, and may have the same thickness as the first adhesive layer 15 or the second adhesive layer 16 as described above. For example, the wiring forming member 2 may be constructed by laminating a metal layer, a third adhesive layer, a second adhesive layer, and a first adhesive layer in that order, or it may be constructed by laminating a metal layer, a second adhesive layer, a first adhesive layer, and a third adhesive layer in that order, but it is not limited to that. 【0114】 Furthermore, the wiring forming member 2 may further include a release film. The release film may be adhered to the side of the adhesive layer 10 opposite to the side of the adhesive layer 10 to which the metal layer 20 is adhered (the side of the second surface 10b of the adhesive layer 10), or to the side of the metal layer 20 opposite to the side of the adhesive layer 10 to which the adhesive layer 10 is adhered (the side of the second surface 20b of the metal layer 20), or to both sides. In this case, the wiring forming member becomes easier to handle, and the work efficiency when forming a wiring layer using the wiring forming member can be improved. 【0115】Furthermore, although the above description used the example of a wiring-forming member being a member formed by bonding an adhesive layer 10 and a metal layer 20, the wiring-forming member 2 in this embodiment may be a set in which the adhesive layer 10 and the metal layer 20 are provided separately, and the adhesive layer 10 can be bonded to the first surface 20a of the metal layer 20 when in use. In this case, since the adhesive layer 10 and the metal layer 20 can be prepared separately (as a set of wiring-forming members), it becomes possible to select a wiring-forming member with a more optimal material configuration, thereby improving the degree of freedom in the work when creating a wiring layer using the wiring-forming member. 【0116】 An adhesive film according to one embodiment of the present disclosure contains conductive particles and a thermosetting resin composition, and the thermal expansion coefficient of the cured adhesive film when heated from 40°C to 260°C is 0.5-3%, 0.5-2.5%, 0.5-2.2%, etc. The cured adhesive film can be prepared in the same manner as the cured adhesive layer described above, and the thermal expansion coefficient can be measured in the same manner. 【0117】 The adhesive film according to this embodiment may have a similar structure to the adhesive layer in the wiring forming member described above. 【0118】 The adhesive film according to this embodiment can be manufactured by the following method. Specifically, first, a thermosetting resin composition and conductive particles are added to a solvent (organic solvent) and dissolved or dispersed by stirring, mixing, kneading, etc., to prepare a varnish composition (varnish-like adhesive composition). Then, the varnish composition is applied to a substrate that has been treated with a mold release agent using a knife coater, roll coater, applicator, comma coater, die coater, etc., and the solvent is evaporated by heating to form an adhesive film on the substrate. 【0119】The solvent used in preparing the varnish composition may be one that has the property of uniformly dissolving or dispersing each component. Examples of such solvents include toluene, acetone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, propyl acetate, and butyl acetate. These solvents can be used individually or in combination of two or more. The stirring, mixing, and kneading during the preparation of the varnish composition can be carried out using, for example, a stirrer, a sieve, a three-roll mill, a ball mill, a bead mill, or a homodisper. 【0120】 The substrate is not particularly limited as long as it has heat resistance that can withstand the heating conditions when the solvent is evaporated. For example, substrates (e.g., films) made of stretched polypropylene (OPP), polyethylene terephthalate (PET), polyethylene naphthalate, polyethylene isophthalate, polybutylene terephthalate, polyolefin, polyacetate, polycarbonate, polyphenylene sulfide, polyamide, polyimide, cellulose, ethylene-vinyl acetate copolymer, polyvinyl chloride, polyvinylidene chloride, synthetic rubber, liquid crystal polymer, etc., can be used. 【0121】 The adhesive film according to this embodiment can be used to connect circuit members and can be suitably used as a circuit connection adhesive film for connecting a first circuit member having a first electrode (for example, a first circuit member in which the first circuit electrode is formed on the main surface of a first substrate) and a second circuit member having a second electrode (for example, a second circuit member in which the second circuit electrode is formed on the main surface of a second substrate) with the first electrode and the second electrode (first circuit electrode and second circuit electrode) facing each other. The adhesive film according to this embodiment can improve the conductivity between electrodes in a circuit connection structure. 【0122】 Examples of the first and second circuit components include chip components such as semiconductor chips, resistor chips, and capacitor chips, and circuit boards such as printed circuit boards. 【0123】 The present disclosure will be described in more detail below with reference to examples. However, the present disclosure is not limited to these examples. 【0124】 <Preparation of adhesive components (thermosetting resin composition)> The following components were prepared as adhesive components. (Thermosetting components) Epoxy resin A: PETG (Pentaerythritol glycidyl ether, manufactured by Resonaq Corporation, trade name, epoxy equivalent: 95 g / eq) Epoxy resin B: EX-321L (Trimethylolpropane triglycidyl ether, manufactured by Nagase ChemteX Corporation, trade name, epoxy equivalent: 128 g / eq) Epoxy resin C: EX-512 (Polyglycerol polyglycidyl ether, manufactured by Nagase ChemteX Corporation, trade name, epoxy equivalent: 167 g / eq) Epoxy resin D: EX-521 (Polyglycerol polyglycidyl ether, manufactured by Nagase ChemteX Corporation, trade name, epoxy equivalent: 184 g / eq) Epoxy resin E: EX-614B (Sorbitol polyglycidyl ether, manufactured by Nagase ChemteX Corporation, trade name, epoxy equivalent: 173 g / eq) Epoxy resin F: HP-4700 (Naphthalene-type polyfunctional epoxy resin, manufactured by DIC Corporation, trade name, epoxy equivalent: 165 g / eq) Epoxy resin G: YL983U (Bisphenol F-type epoxy resin, manufactured by Mitsubishi Chemical Corporation, trade name, epoxy equivalent: 170 g / eq) Phenolic resin A: KA-1160 (Cresol novolac-type phenolic resin, manufactured by DIC Corporation, trade name, hydroxyl group equivalent: 117 g / eq) Note that the hydroxyl group equivalent of the phenolic resin was determined by the measurement method described below. Phenolic resin B: KA-1165 (Cresol novolac-type phenolic resin, manufactured by DIC Corporation, trade name, hydroxyl group equivalent: 119 g / eq) Note that the hydroxyl group equivalent of the phenolic resin was determined by the measurement method described below. (Thermoplastic resin) Phenoxy resin: ZX-1356-2 (BisA / F type phenoxy resin, manufactured by Nippon Steel Chemical & Material Co., Ltd., product name) (Curing accelerator) Curing accelerator: G-8009L (Isocyanate mask imidazole, manufactured by Daiichi Kogyo Seiyaku Co., Ltd., product name) (Conductive particles) Cu particles: Cu-HWQ (manufactured by Fukuda Metal Foil & Powder Industry Co., Ltd., average particle size 10 μm) (Filler) Silica particles: SC2050KC (Phenylaminosilane treated silica filler, average particle size 0.5 μm, manufactured by Admatex Co., Ltd., product name) 【0125】 <Method for measuring hydroxyl group equivalent> 1 g of the sample was accurately weighed into a round-bottom flask, and then 5 mL of acetic anhydride and pyridine reagent were accurately weighed in. Next, an air condenser was attached to the flask and it was heated at 100°C for 1 hour. After the flask cooled, 1 mL of water was added, and the flask was heated again at 100°C for 10 minutes. After the flask cooled again, the air condenser and the neck of the flask were washed with 5 mL of neutralized methanol, and 1 mL of phenolphthalein reagent was added. The solution thus obtained was titrated with a 0.1 mol / L potassium hydroxide-ethanol solution to determine the hydroxyl value. From the obtained hydroxyl value, the hydroxyl group equivalent (g / eq), converted to the mass per 1 mol (1 eq) of hydroxyl groups, was calculated. 【0126】 <Preparation of Wiring Forming Components> A coating solution for forming an adhesive layer was prepared by blending each component in the amounts shown in Table 1, with the remainder being methyl ethyl ketone (MEK). The blending amounts were based on the total mass or total volume of the coating solution. This coating solution was applied to one side (surface roughness Rz: 3.0 μm) of copper foil (manufactured by Mitsui Mining & Smelting Co., Ltd., product name: "3EC-M3-VLP", thickness: 12 μm) using a coating device (manufactured by Yasui Seiki Co., Ltd., product name: Precision Coating Machine), and a 25 μm thick adhesive layer was formed on the copper foil by hot air drying at 70°C for 5 minutes. A wiring forming component was thus prepared. 【0127】 <Evaluation of Toughness> The prepared coating solution was applied to one side of a PET film (thickness 50 μm) using a coating device (manufactured by Yasui Seiki Co., Ltd., product name: Precision Coating Machine), and MEK was removed by hot air drying at 70°C for 5 minutes to create a 25 μm thick adhesive layer on the PET film to obtain a test specimen. An incision was made in the obtained test specimen with a cutter, and the film was evaluated as follows: A if it did not crack, B if it cracked slightly, and C if it cracked significantly. If the evaluation was A or B, it was judged that the film had sufficient toughness. 【0128】<Measurement of CTE> Test specimens measuring 30 mm x 4 mm were prepared from the fabricated wiring forming material, and the coefficient of thermal expansion was measured using a thermomechanical analyzer (product name "TMA / SS7100", manufactured by Hitachi High-Tech Corporation). The measurement mode was tensile mode, the measurement load was 50 mN, the measurement atmosphere was atmospheric, and the heating rate was 5 °C / min. The measurement results from 40 to 260 °C in the second run were taken as the coefficient of thermal expansion. The results are shown in Table 1. 【0129】 <Measurement of Tg> Using the fabricated wiring forming material, test specimens measuring 20 mm x 10 mm were prepared, and Tg (tanδ peak) was measured using a dynamic viscoelasticity measuring device (manufactured by SII Nanotechnology Co., Ltd., product name "DMS6100") under the conditions of frequency 1 Hz, measurement temperature 40°C to 260°C, and heating rate 10°C / min. 【0130】 【0131】 1, 1a, 1c, 1e...Wiring forming members, 1d, 1f...Wiring layer, 1b...Wiring forming member, 2...Wiring forming member, 10, 10c, 10d, 10A, 10B...Adhesive layer, 10a...First surface, 10b...Second surface, 10e...First adhesive layer, 10f...Second adhesive layer, 12, 12a...Conductive particles, 14...Adhesive component, 15...First adhesive layer, 16...Second adhesive layer, 17...Adhesive component, 20...Metal layer, 20a...First surface, 20b...Second surface, 30...Base material, 32...Wiring.

Claims

1. An adhesive film containing an epoxy resin and a phenolic resin, wherein the epoxy equivalent of the epoxy resin is 150 g / eq or less.

2. The adhesive film according to claim 1, further containing conductive particles.

3. The adhesive film according to claim 2, wherein the conductive particles are copper particles.

4. The adhesive film according to any one of claims 1 to 3, wherein the epoxy resin has three or more epoxy groups.

5. The adhesive film according to any one of claims 1 to 3, wherein the epoxy resin is pentaerythritol glycidyl ether.

6. A metal-layered adhesive film comprising a metal layer and an adhesive layer disposed on the metal layer, wherein the adhesive layer contains an epoxy resin and a phenolic resin, and the epoxy equivalent of the epoxy resin is 150 g / eq or less.

7. The adhesive film with a metal layer according to claim 6, further containing conductive particles.

8. The adhesive film with a metal layer according to claim 7, wherein the conductive particles are copper particles.

9. The adhesive film with a metal layer according to any one of claims 6 to 8, wherein the epoxy resin has three or more epoxy groups.

10. The adhesive film with a metal layer according to any one of claims 6 to 8, wherein the epoxy resin is pentaerythritol glycidyl ether.

11. A metal-layered adhesive film according to any one of claims 6 to 8, used for forming wiring.

12. A wiring forming member comprising an adhesive layer and a metal layer, wherein the adhesive layer can be bonded to the metal layer during use, the adhesive layer containing an epoxy resin and a phenolic resin, and the epoxy equivalent of the epoxy resin being 150 g / eq or less.

13. The wiring forming member according to claim 12, further containing conductive particles.

14. The wiring forming member according to claim 13, wherein the conductive particles are copper particles.

15. The wiring forming member according to any one of claims 12 to 14, wherein the epoxy resin has three or more epoxy groups.

16. The wiring forming member according to any one of claims 12 to 14, wherein the epoxy resin is pentaerythritol glycidyl ether.

17. A method for forming a wiring layer, comprising the steps of: preparing a metal-layered adhesive film according to any one of claims 6 to 8; preparing a substrate on which wiring is formed; arranging the metal-layered adhesive film on the surface of the substrate on which the wiring is formed so as to cover the wiring, with the adhesive layer facing the substrate; heat-pressing the metal-layered adhesive film to the substrate; and performing a patterning treatment on the metal layer.

18. A method for forming a wiring layer, comprising the steps of: preparing a wiring-forming member according to any one of claims 12 to 14; preparing a substrate on which wiring is formed; arranging the wiring-forming member on the surface of the substrate on which the wiring is formed so as to cover the wiring, with the adhesive layer facing the substrate; heat-pressing the wiring-forming member to the substrate; and performing a patterning treatment on the metal layer.

19. A wiring forming member comprising: a substrate having wiring; and a cured product of the adhesive layer of a metal-layered adhesive film according to any one of claims 6 to 8, disposed on the substrate so as to cover the wiring, wherein the wiring and the metal layer of the metal-layered adhesive film or another wiring formed from the metal layer are electrically connected.

20. A wiring forming member comprising: a substrate having wiring; and a cured product of the adhesive layer of a wiring forming member according to any one of claims 12 to 14, disposed on the substrate so as to cover the wiring, wherein the wiring and the metal layer of the wiring forming member or another wiring formed from the metal layer are electrically connected.

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