Temporary fixation material

Abstract

To provide a temporary fixation material which can suppress positional deviation of an electronic component.SOLUTION: There is provided a temporary fixation material capable of temporarily fixing an electronic component 70 when the electronic component 70 is sealed by a sealing material 60 in a step of manufacturing an electronic device, wherein a laminate 100 having an epoxy resin layer 10 capable of fixing an electronic component, a base material layer 40, and an adhesive resin layer (B) 50 stuck to a support substrate 80 is formed in a step prior to a step of sealing the electronic component 70 by the sealing material 60, and when the total content of the resin component in the epoxy resin layer 10 is 100 pts.mass, the content of the epoxy resin in the epoxy resin layer 10 is 10 pts.mass or more.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a temporary fixing material. [Background technology]

[0002] 2. Description of the Related Art A fan-out type WLP (wafer level package) has been developed as a technology capable of reducing the size and weight of electronic devices (eg, semiconductor devices). In eWLB (Embedded Wafer Level Ball Grid Array), which is one of the methods for manufacturing fan-out type WLP, multiple electronic components such as semiconductor chips are temporarily fixed in a spaced-apart state on a temporary fixing material (e.g., adhesive film, etc.) attached to a support substrate, and the multiple electronic components are collectively sealed with a sealing material. Here, the temporary fixing material needs to be fixed to the electronic components and the support substrate during the sealing process, etc., and needs to be removed from the sealed electronic components together with the support substrate after sealing.

[0003] As a technique relating to a manufacturing method of such an electronic device, for example, the technique described in Patent Document 1 can be given.

[0004] Patent document 1 describes a method for manufacturing a semiconductor package, including the steps of: arranging a semiconductor chip on a semiconductor back surface protective film arranged on an adhesive sheet; curing the semiconductor back surface protective film after the step of arranging the semiconductor chip on the semiconductor back surface protective film; and encapsulating the semiconductor chip with resin after the step of curing the semiconductor back surface protective film. Patent Document 1 describes that an object of the present invention is to provide a method for manufacturing a semiconductor package that can prevent misalignment of a semiconductor chip caused by thermal curing shrinkage of a resin. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2017-92335 A Summary of the Invention [Problem to be solved by the invention]

[0006] When electronic components are placed on the temporary fixing material and then sealed with a sealing material, the positions of the electronic components may become misaligned (hereinafter, also referred to as "displacement of the electronic components").

[0007] The present invention has been made in consideration of the above circumstances, and provides a temporary fixing material capable of suppressing displacement of electronic components. [Means for solving the problem]

[0008] According to the present invention, there is provided the following temporary fixing material.

[0009] [1] A temporary fixing material capable of temporarily fixing an electronic component when sealing the electronic component with a sealing material in a manufacturing process of an electronic device, In a step prior to the step of sealing the electronic components with a sealing material, a laminate is formed which includes, in this order, an epoxy resin layer to which the electronic components can be fixed, a base layer, and an adhesive resin layer (B) to be attached to a support substrate; A temporary fixing material, wherein the content of the epoxy resin in the epoxy resin layer is 10 parts by mass or more when the total content of resin components in the epoxy resin layer is 100 parts by mass. [2] The temporary fixing material according to [1] above, wherein the epoxy resin layer is in an uncured or semi-cured state. [3] The temporary fixing material according to [1] or [2] above, wherein the epoxy resin layer further contains an inorganic filler. [4] The temporary fixing material according to any one of the above [1] to [3], wherein the epoxy resin layer further contains a curing agent. [5] The temporary fixing material according to any one of the above [1] to [4], wherein the insulating resin layer obtained by curing the epoxy resin layer is capable of forming a rewiring layer. [6] The temporary fixing material according to any one of the above [1] to [5], wherein the adhesive strength of the adhesive resin layer (B) decreases in response to an external stimulus. [7] The temporary fixing material according to [6] above, wherein the adhesive strength of the adhesive resin layer (B) decreases when heated. [8] The temporary fixing material according to [7] above, wherein the adhesive resin layer (B) contains at least one selected from the group consisting of a gas-generating component and heat-expandable microspheres. [9] The laminate further comprises an adhesive resin layer (A), The temporary fixing material according to any one of the above [1] to [8], wherein the adhesive resin layer (A) is located between the epoxy resin layer and the base material layer.

[10] The temporary fixing material according to [9] above, wherein the total content of the gas-generating component and the heat-expandable microspheres in the adhesive resin layer (A) is less than 0.1% by mass, when the entire adhesive resin layer (A) is taken as 100% by mass.

[11] The temporary fixing material according to [9] or

[10] , wherein the adhesive resin layer (A) contains one or more selected from the group consisting of (meth)acrylic adhesive resins, silicone adhesive resins, urethane adhesive resins, olefin adhesive resins, and styrene adhesive resins.

[12] The temporary fixing material according to any one of the above [1] to

[11] , wherein the sealing material includes an epoxy resin-based sealing material.

[13] The temporary fixing material according to any one of [1] to

[12] above, wherein the electronic device includes a fan-out type package. Effect of the Invention

[0010] According to the present invention, a temporary fixing material capable of suppressing displacement of electronic components can be provided. [Brief description of the drawings]

[0011] [Figure 1] 1A to 1C are diagrams illustrating an example of a method for manufacturing an electronic device according to an embodiment of the present invention. [Diagram 2] 1A to 1C are diagrams illustrating an example of a method for manufacturing an electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In all drawings, similar components are given the same reference numerals and the description will be omitted as appropriate. In addition, the drawings are schematic views and do not necessarily correspond to the actual dimensional ratios. Unless otherwise specified, the expression "A to B" regarding a numerical range means greater than or equal to A and less than or equal to B. In addition, "(meth)acrylic" means acrylic, methacrylic, or both acrylic and methacrylic.

[0013] [Temporary fixing material] 1 and 2 are diagrams illustrating an example of a method for manufacturing an electronic device according to the present embodiment. The temporary fixing material of the present embodiment is a temporary fixing material capable of temporarily fixing an electronic component when the electronic component is sealed with a sealing material in the manufacturing process of an electronic device, and in a step prior to the step of sealing the electronic component with a sealing material, a laminate is formed having, in this order, an epoxy resin layer capable of fixing the electronic component, a base material layer, and an adhesive resin layer (B) attached to a support substrate, and the content of the epoxy resin in the epoxy resin layer is 10 parts by mass or more when the total content of the resin components in the epoxy resin layer is 100 parts by mass.

[0014] As described above, a manufacturing method for an electronic device (e.g., an electronic device including a fan-out type package) includes a step of temporarily fixing a plurality of electronic components, such as semiconductor chips, in a spaced-apart state on a temporary fixing material (e.g., an adhesive film, etc.) attached to a substrate, and collectively sealing the plurality of electronic components with a sealing material. When electronic components are placed on the temporary fixing material and then sealed with a sealing material, the positions of the electronic components may become misaligned (hereinafter, also referred to as "displacement of the electronic components"). The present inventors have conducted extensive research to achieve the above object, and have found that in a process of sealing electronic components, the electronic components are not able to withstand the pressure caused by the flow of the sealing material, resulting in displacement of the electronic components.

[0015] In some cases, a manufacturing method for an electronic device includes a step of forming a redistribution layer after sealing an electronic component. If the electronic component is displaced in the sealing step, the electronic component will move to a location different from the intended location in the step of forming the redistribution layer. Therefore, when forming the redistribution layer, there are cases where the wiring is displaced due to the displacement of the electronic component. If the wiring is displaced, there is a risk of reducing the reliability of the electronic device, such as by causing a break in the wiring.

[0016] In the prior art relating to temporary fixing materials used when sealing electronic components with a sealing material, for example, temporary fixing materials with high adhesive strength have been considered in order to eliminate positional deviation of electronic components. According to the study by the present inventors, it has become clear that a temporary fixing material with high adhesive strength may be damaged because the peeling force required for peeling off the temporary fixing material is also high. It has also become clear that in the process of removing the temporary fixing material together with the supporting substrate from the encapsulated electronic component after encapsulation, a part of the adhesive resin (hereinafter also referred to as glue) contained in the temporary fixing material may remain on the electronic component side (hereinafter also referred to as glue residue). That is, according to the investigations of the present inventors, it has become clear that there are cases where there is a trade-off between misalignment of electronic components and adhesive residue.

[0017] The present inventors have conducted extensive research to achieve the above object, and as a result, have found that by using a temporary fixing material including an epoxy resin layer capable of fixing electronic components, the layer to which the electronic components are fixed can be made of a cured resin in a sealing step, and the electronic components can be fixed with a stronger force, thereby suppressing positional deviation of the electronic components.

[0018] In addition, the temporary fixing material of the present embodiment can use an insulating resin layer formed by hardening an epoxy resin layer as a rewiring layer. In other words, since it does not include a process of peeling off the layer that directly fixes the electronic component, it is possible to suppress adhesive residue on the electronic component side. According to the present invention, it is further possible to provide a temporary fixing material that can suppress the occurrence of adhesive residue and the misalignment of electronic components.

[0019] Furthermore, a conventional redistribution layer is, for example, a layer made of sintered polyimide. Polyimide is an expensive material. In addition, a process at a high temperature (e.g., 230° C.) is required to sinter polyimide. As described above, by using the temporary fixing material of the present embodiment, the insulating resin layer formed by curing the epoxy resin layer can be used as the rewiring layer. According to the present invention, since the positional deviation of the electronic components can be suppressed, the positional deviation of the wiring caused by the positional deviation of the electronic components can be suppressed when forming the rewiring layer. Therefore, according to the present invention, it is possible to provide a temporary fixing material that can suppress the occurrence of breakage due to the positional deviation of the wiring and can obtain an electronic device with improved reliability. The present invention further provides a temporary fixing material that enables a rewiring layer to be formed at low cost through a low-temperature process.

[0020] The temporary fixing material of the present embodiment forms a laminate having an epoxy resin layer, a base material layer, and an adhesive resin layer (B) in this order in a step prior to the step of sealing the electronic components with a sealing material. Here, the laminate will be specifically described with reference to FIG. An example of the step before the step of sealing the electronic components with a sealing material is the step (A) of preparing a structure (a) in the manufacturing method of an electronic device described later. In the step before the step of sealing the electronic components with a sealing material, the temporary fixing material of the present embodiment forms a laminate 100 including an epoxy resin layer 10, a base layer 40, and an adhesive resin layer (B) 50 in this order.

[0021] The form of the temporary fixing material of this embodiment is not particularly limited as long as it is a material that is capable of forming a laminate 100 having an epoxy resin layer 10, a base material layer 40, and an adhesive resin layer (B) 50 in this order in a process prior to the process of sealing the electronic components with a sealing material. Examples of the temporary fixing material of this embodiment include a film set including an epoxy film including an epoxy resin layer 10 and an adhesive film including a base material layer 40 and an adhesive resin layer (B) 50; a laminated film including an epoxy resin layer 10, a base material layer 40, and an adhesive resin layer (B) 50 in this order; and the like.

[0022] Hereinafter, a film set including an epoxy film including an epoxy resin layer 10, and an adhesive film including a base layer 40 and an adhesive resin layer (B) 50 will be specifically described.

[0023] The epoxy film of the present embodiment is, for example, a film in which a base film, an epoxy resin layer 10, and a protective film are laminated. An example of the base film is a polyethylene terephthalate film (PET film). An example of the protective film is a biaxially oriented polypropylene film (OPP film). The epoxy film of the present embodiment may be a commercially available epoxy film, for example, AJINOMOTO BUILDUP FILM (registered trademark, manufactured by Ajinomoto Fine-Techno Co., Ltd.).

[0024] The adhesive film of this embodiment is a film in which a base layer 40 and an adhesive resin layer (B) 50 are laminated together, and preferably a film in which an adhesive resin layer (A), a base layer 40 and an adhesive resin layer (B) 50 are laminated together. The pressure-sensitive adhesive film of the present embodiment may be appropriately provided with a protective film or the like.

[0025] The laminated film having an epoxy resin layer 10, a base layer 40, and an adhesive resin layer (B) 50 in this order, which is one aspect of the temporary fixing material of this embodiment, may further include a protective film or the like as appropriate.

[0026] In the epoxy film, adhesive film, and laminate film of this embodiment, preferred aspects of the epoxy resin layer 10, base material layer 40, adhesive resin layer (B) 50 and adhesive resin layer (A) are the same as the preferred aspects of each layer of the laminate 100 described below.

[0027] Each layer constituting the laminate 100 will now be described.

[0028] <Epoxy resin layer> The epoxy resin layer 10 is a layer to which electronic components can be attached. The epoxy resin layer 10 contains an epoxy resin. Examples of epoxy resins include bixylenol type epoxy resins, bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, bisphenol AF type epoxy resins, dicyclopentadiene type epoxy resins, trisphenol type epoxy resins, naphthol novolac type epoxy resins, phenol novolac type epoxy resins, tert-butyl-catechol type epoxy resins, naphthalene type epoxy resins, naphthol type epoxy resins, anthracene type epoxy resins, glycidylamine type epoxy resins, glycidyl ester type epoxy resins, cresol novolac type epoxy resins, biphenyl type epoxy resins, linear aliphatic epoxy resins, epoxy resins having a butadiene structure, alicyclic epoxy resins, heterocyclic epoxy resins, spiro ring-containing epoxy resins, cyclohexane dimethanol type epoxy resins, naphthylene ether type epoxy resins, trimethylol type epoxy resins, tetraphenylethane type epoxy resins, and the like. The epoxy resin may be used alone or in combination of two or more kinds.

[0029] The content of the epoxy resin in the epoxy resin layer 10 is 10 parts by mass or more when the total content of the resin components in the epoxy resin layer 10 is 100 parts by mass. The content of the epoxy resin in the epoxy resin layer 10 is preferably 15 parts by mass or more, more preferably 20 parts by mass or more, even more preferably 50 parts by mass or more, and is preferably 95 parts by mass or less, more preferably 90 parts by mass or less, even more preferably 80 parts by mass or less, and even more preferably 70 parts by mass or less, when the total content of the resin components in the epoxy resin layer 10 is 100 parts by mass.

[0030] The total content of the resin components in the epoxy resin layer 10 is preferably 5 mass% or more, more preferably 10 mass% or more, even more preferably 15 mass% or more, and even more preferably 20 mass% or more from the viewpoint of further suppressing misalignment of electronic components, and is preferably 80 mass% or less, more preferably 70 mass% or less, even more preferably 50 mass% or less, even more preferably 45 mass% or less, and even more preferably 40 mass% or less, from the viewpoint of further reducing the linear expansion coefficient of the cured product of the epoxy resin layer 10.

[0031] From the viewpoint of appropriately adjusting the linear expansion coefficient of the cured product of the epoxy resin layer 10, the epoxy resin layer 10 preferably further contains an inorganic filler. Examples of inorganic fillers include silica, alumina, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate, barium zirconate titanate, barium zirconate, calcium zirconate, zirconium phosphate, and zirconium tungstate phosphate. Of these, silica is preferable. The inorganic filler may be used alone or in combination of two or more kinds.

[0032] Average particle size of inorganic filler D 50 From the viewpoint of reducing the surface roughness of the epoxy resin layer 10, the thickness is preferably 5.0 μm or less, more preferably 2.5 μm or less, even more preferably 2.0 μm or less, and even more preferably 1.5 μm or less, and the lower limit is not particularly limited, but may be, for example, 0.01 μm or more, or 0.1 μm or more. Average particle size of inorganic filler D 50means the particle size value when the cumulative frequency is 50% in a volume-based cumulative frequency distribution curve measured by a laser diffraction / scattering method. Note that it is preferable to use a measurement sample in which an inorganic filler is dispersed in water by ultrasonic waves.

[0033] The inorganic filler may be surface-treated in order to improve the moisture resistance and dispersibility of the inorganic filler.

[0034] When the total content of all components in the epoxy resin layer 10 is taken as 100 mass%, the content of the inorganic filler in the epoxy resin layer 10 is preferably 20 mass% or more, more preferably 30 mass% or more, even more preferably 50 mass% or more, even more preferably 55 mass% or more, and even more preferably 60 mass% or more, from the viewpoint of further reducing the linear expansion coefficient of the cured product of the epoxy resin layer 10, and is preferably 95 mass% or less, more preferably 90 mass% or less, even more preferably 85 mass% or less, and even more preferably 80 mass% or less, from the viewpoint of further improving the mechanical strength of the epoxy resin layer 10.

[0035] The epoxy resin layer 10 preferably further comprises a hardener. The curing agent is not particularly limited as long as it is capable of curing an epoxy resin, and examples thereof include active ester-based curing agents, cyanate ester-based curing agents, phenol-based curing agents, naphthol-based curing agents, benzoxazine-based curing agents, and carbodiimide-based curing agents. The curing agent may be used alone or in combination of two or more kinds.

[0036] The content of the curing agent in the epoxy resin layer 10 is not particularly limited as long as it is an amount capable of curing the epoxy resin.

[0037] The epoxy resin layer 10 may contain, in addition to the above-mentioned components, for example, components such as a resin other than an epoxy resin, a curing accelerator, an organic filler, a flame retardant, and a colorant.

[0038] The epoxy resin layer 10 is preferably in an uncured or semi-cured state. It is preferable that the insulating resin layer 20 formed by curing the epoxy resin layer 10 can form the rewiring layer 30 .

[0039] The linear expansion coefficient of the insulating resin layer 20 obtained by curing the epoxy resin layer 10 from 30°C to 150°C is, from the viewpoint of further suppressing misalignment of electronic components, preferably 100 ppm / K or less, more preferably 80 ppm / K or less, even more preferably 60 ppm / K or less, even more preferably 50 ppm / K or less, even more preferably 40 ppm / K or less, even more preferably 30 ppm / K or less, and even more preferably 25 ppm / K or less, and the lower limit is not particularly limited, but may be, for example, 5 ppm / K or more, or 10 ppm / K or more.

[0040] The glass transition temperature of the insulating resin layer 20 obtained by curing the epoxy resin layer 10 is, from the viewpoint of further suppressing misalignment of electronic components, preferably 130°C or higher, more preferably 150°C or higher, even more preferably 160°C or higher, and even more preferably 170°C or higher. The upper limit is not particularly limited, but may be, for example, 200°C or lower, or 190°C or lower. The glass transition temperature of the insulating resin layer 20 can be measured, for example, by a dynamic viscoelasticity measuring device.

[0041] The thickness of the epoxy resin layer 10 is preferably 1 μm or more, more preferably 3 μm or more, even more preferably 5 μm or more, and even more preferably 8 μm or more, and is preferably 500 μm or less, more preferably 400 μm or less, even more preferably 300 μm or less, even more preferably 250 μm or less, even more preferably 200 μm or less, even more preferably 150 μm or less, even more preferably 100 μm or less, even more preferably 70 μm or less, and even more preferably 50 μm or less.

[0042] <Base material layer> The base layer 40 is not particularly limited, but may be, for example, a resin film. The resin constituting the resin film may be any known thermoplastic resin, including, for example, one or more selected from polyolefins such as polyethylene, polypropylene, poly(4-methyl-1-pentene), and poly(1-butene); polyesters such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polyamides such as nylon-6, nylon-66, and polymetaxylene adipamide; polyacrylates; polymethacrylates; polyvinyl chloride; polyvinylidene chloride; polyimides; polyetherimides; ethylene-vinyl acetate copolymers; polyacrylonitrile; polycarbonates; polystyrenes; ionomers; polysulfones; polyethersulfones; and polyphenylene ethers. Among these, the resin constituting the resin film is preferably one or more selected from the group consisting of polypropylene, polyethylene terephthalate, polyethylene naphthalate, polyamide and polyimide, from the viewpoint of an excellent balance of transparency, mechanical strength, price, etc., and more preferably at least one selected from the group consisting of polyethylene terephthalate and polyethylene naphthalate.

[0043] The substrate layer 40 may be a single layer or two or more layers. The form of the resin film used to form the base layer 40 may be a stretched film or a film stretched uniaxially or biaxially. From the viewpoint of improving the mechanical strength of the base layer 40, however, a film stretched uniaxially or biaxially is preferable. The resin film may be subjected to a surface treatment, specifically, a corona treatment, a plasma treatment, an undercoat treatment, a primer coat treatment or the like.

[0044] The thickness of the base layer 40 is preferably 1 μm or more, more preferably 5 μm or more, and even more preferably 10 μm or more, and is preferably 500 μm or less, more preferably 300 μm or less, and even more preferably 250 μm or less.

[0045] <Adhesive resin layer (B)> The adhesive resin layer (B) 50 is a layer that is attached to a supporting substrate. From the viewpoint of easily peeling off the adhesive resin layer (B) 50 from the supporting substrate, the adhesive strength of the adhesive resin layer (B) 50 is preferably reduced by an external stimulus. Here, examples of the adhesive resin layer (B) 50 whose adhesive strength decreases with an external stimulus include a heat peelable adhesive resin layer whose adhesive strength decreases with heating, a radiation peelable adhesive resin layer whose adhesive strength decreases with radiation, etc. Among these, a heat peelable adhesive resin layer whose adhesive strength decreases with heating is preferred. Examples of heat-peelable adhesive resin layers include adhesive resin layers made of a heat-expandable adhesive containing a gas-generating component, a heat-expandable adhesive containing heat-expandable microspheres that can expand to reduce adhesive strength, and a heat-expandable adhesive whose adhesive strength is reduced as a result of the adhesive component undergoing a crosslinking reaction due to heat. The adhesive resin layer (B) 50 preferably contains at least one member selected from the group consisting of a gas-generating component and heat-expandable microspheres.

[0046] In this embodiment, the thermal expansion adhesive used in the adhesive resin layer (B) 50 is an adhesive whose adhesive strength is reduced or lost when heated at a temperature exceeding, for example, 170° C. For example, a material can be selected that does not peel off at temperatures below 170° C. but peels off at temperatures exceeding 170° C., and it is preferable that the adhesive resin layer (B) 50 has an adhesive strength sufficient to prevent it from peeling off from the support substrate during the manufacturing process of the electronic device. Here, the decrease or loss of adhesive strength due to heating at a temperature exceeding 170°C can be evaluated, for example, by attaching the adhesive resin layer (B) 50 side of the adhesive film to a stainless steel plate, performing a heat treatment at 140°C for 1 hour, and then heating at a temperature exceeding 170°C for 2 minutes, and then measuring the peel strength from the stainless steel plate. The specific heating temperature when heating at a temperature exceeding 170°C is set to a temperature higher than the temperature at which gas is generated or the temperature at which the thermally expandable microspheres thermally expand, and is appropriately set depending on the type of gas generated or the type of thermally expandable microspheres. In this embodiment, the loss of adhesive strength refers to, for example, a case in which the 180° peel strength measured under conditions of 23°C and a tensile speed of 300 mm / min is less than 0.5 N / 25 mm.

[0047] Examples of gas generating components that can be used in the thermal expansion type pressure sensitive adhesive include azo compounds, azide compounds, and Meldrum's acid derivatives. In addition, inorganic foaming agents such as ammonium carbonate, ammonium hydrogen carbonate, sodium hydrogen carbonate, ammonium nitrite, sodium boron hydroxide, and various azides, water, fluorinated alkane compounds such as trichloromonofluoromethane and dichloromonofluoromethane, azo compounds such as azobisisobutyronitrile, azodicarbonamide, and barium azodicarboxylate, paratoluenesulfonylhydrazide, diphenylsulfone-3,3'-disulfonylhydrazide, 4,4'-oxybis(benzenesulfonyl)hydrazide, and the like can be used. Also usable are organic foaming agents such as hydrazine compounds such as p-toluenesulfonylsemicarbazide and 4,4'-oxybis(benzenesulfonylsemicarbazide); triazole compounds such as 5-morpholyl-1,2,3,4-thiatriazole; and N-nitroso compounds such as N,N'-dinitrosopentamethylenetetramine and N,N'-dimethyl-N,N'-dinitrosoterephthalamide. The gas generating component may be added to the adhesive resin (B1) or may be directly bonded to the adhesive resin (B1).

[0048] As the heat-expandable microspheres used in the heat-expandable pressure-sensitive adhesive, for example, a microencapsulated foaming agent can be used. Examples of such heat-expandable microspheres include microspheres in which a substance that is easily gasified and expanded by heating, such as isobutane, propane, or pentane, is encapsulated in an elastic shell. Examples of materials constituting the shell include vinylidene chloride-acrylonitrile copolymer, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, polyacrylonitrile, polyvinylidene chloride, and polysulfone. Heat-expandable microspheres can be produced, for example, by a coacervation method or an interfacial polymerization method. The heat expandable microspheres can be added to the adhesive resin (B1).

[0049] The content of at least one selected from the gas-generating component and the heat-expandable microspheres can be appropriately set depending on the expansion ratio and adhesive strength reduction of the heat-peelable adhesive resin layer (B) 50, and is not particularly limited, but is, for example, 1 part by mass or more and 150 parts by mass or less, preferably 10 parts by mass or more and 130 parts by mass or less, and more preferably 12 parts by mass or more and 100 parts by mass or less, relative to 100 parts by mass of the adhesive resin (B1) in the heat-peelable adhesive resin layer (B) 50. It is preferable to design the temperature at which gas is generated and the temperature at which the heat-expandable microspheres expand are above 170°C.

[0050] Examples of the adhesive resin (B1) constituting the thermally expandable adhesive agent include (meth)acrylic adhesive resin (b), urethane adhesive resin, silicone adhesive resin, polyolefin adhesive resin, polyester adhesive resin, polyamide adhesive resin, fluorine adhesive resin, styrene-diene block copolymer adhesive resin, etc. Among these, (meth)acrylic adhesive resin (b) is preferred.

[0051] The (meth)acrylic adhesive resin (b) used in the adhesive resin layer (B) 50 may be, for example, a copolymer containing a (meth)acrylic acid alkyl ester monomer unit (b1) and a monomer unit (b2) having a functional group capable of reacting with a crosslinking agent. In this embodiment, the (meth)acrylic acid alkyl ester means an acrylic acid alkyl ester, a methacrylic acid alkyl ester, or a mixture thereof.

[0052] The (meth)acrylic adhesive resin (b) according to this embodiment can be obtained, for example, by copolymerizing a monomer mixture containing a (meth)acrylic acid alkyl ester monomer (b1) and a monomer (b2) having a functional group capable of reacting with a crosslinking agent.

[0053] Examples of the monomer (b1) forming the (meth)acrylic acid alkyl ester monomer unit (b1) include (meth)acrylic acid alkyl esters having an alkyl group with about 1 to 12 carbon atoms. Preferred are (meth)acrylic acid alkyl esters having an alkyl group with 1 to 8 carbon atoms. Specific examples include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, and 2-ethylhexyl methacrylate. These may be used alone or in combination of two or more. In the (meth)acrylic adhesive resin (b) according to this embodiment, the content of the (meth)acrylic acid alkyl ester monomer unit (b1) is preferably from 10 mass% to 98.9 mass%, more preferably from 50 mass% to 97 mass%, and even more preferably from 85 mass% to 95 mass%, when the sum of all monomer units in the (meth)acrylic adhesive resin (b) is 100 mass%.

[0054] Examples of the monomer (b2) that forms the monomer unit (b2) having a functional group that can react with a crosslinking agent include acrylic acid, methacrylic acid, itaconic acid, mesaconic acid, citraconic acid, fumaric acid, maleic acid, itaconic acid monoalkyl ester, mesaconic acid monoalkyl ester, citraconic acid monoalkyl ester, fumaric acid monoalkyl ester, maleic acid monoalkyl ester, glycidyl acrylate, glycidyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, acrylamide, methacrylamide, tertiary-butylaminoethyl acrylate, and tertiary-butylaminoethyl methacrylate. Preferred are acrylic acid, methacrylic acid, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, acrylamide, methacrylamide, and the like. These may be used alone or in combination of two or more. In the (meth)acrylic adhesive resin (b) according to this embodiment, the content of the monomer unit (b2) is preferably from 1 to 40% by mass, more preferably from 1 to 20% by mass, and even more preferably from 1 to 10% by mass, when the sum of all monomer units in the (meth)acrylic adhesive resin (b) is taken as 100% by mass.

[0055] The (meth)acrylic adhesive resin (b) according to this embodiment may further contain, in addition to the monomer unit (b1) and the monomer unit (b2), a bifunctional monomer unit (b3) or a specific comonomer unit having surfactant properties (hereinafter referred to as a polymerizable surfactant). The polymerizable surfactant has the property of copolymerizing with the monomers (b1), (b2) and (b3), and also acts as an emulsifier in the case of emulsion polymerization.

[0056] Examples of the monomer (b3) forming the bifunctional monomer unit (b3) include allyl methacrylate, allyl acrylate, divinylbenzene, vinyl methacrylate, vinyl acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tetraethylene glycol di(meth)acrylate, and, for example, those having diacrylate or dimethacrylate at both ends and a main chain structure of propylene glycol type (e.g., Nippon Oil & Fats Corporation, trade names: PDP-200, PDP-400, ADP-200, ADP-400), tetramethylene glycol type (e.g., Nippon Oil & Fats Corporation, trade names: ADT-250, ADT-850) and mixtures thereof (e.g., Nippon Oil & Fats Corporation, trade names: ADET-1800, ADPT-4000).

[0057] In the (meth)acrylic adhesive resin (b) according to this embodiment, the content of the monomer unit (b3) is preferably from 0.1 to 30% by mass, more preferably from 0.1 to 20% by mass, even more preferably from 0.1 to 15% by mass, and even more preferably from 0.1 to 5% by mass, when the sum of all monomer units in the (meth)acrylic adhesive resin (b) is 100% by mass.

[0058] Examples of polymerizable surfactants include those in which a polymerizable 1-propenyl group has been introduced into the benzene ring of polyoxyethylene nonylphenyl ether (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.; trade names: Aqualon RN-10, RN-20, RN-30, RN-50, etc.), those in which a polymerizable 1-propenyl group has been introduced into the benzene ring of an ammonium salt of a sulfate ester of polyoxyethylene nonylphenyl ether (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.; trade names: Aqualon HS-10, HS-20, HS-1025, etc.), and sulfosuccinic acid diesters having a polymerizable double bond in the molecule (manufactured by Kao Corporation; trade names: Latemul S-120A, S-180A, etc.). In the (meth)acrylic adhesive resin (b) according to this embodiment, the content of the polymerizable surfactant is preferably from 0.1% by mass to 30% by mass, more preferably from 0.1% by mass to 20% by mass, even more preferably from 0.1% by mass to 15% by mass, and even more preferably from 0.1% by mass to 5% by mass, when the sum of all monomer units in the (meth)acrylic adhesive resin (b) is taken as 100% by mass.

[0059] The (meth)acrylic adhesive resin (b) according to this embodiment may further contain, if necessary, a monomer unit formed from a monomer having a polymerizable double bond, such as vinyl acetate, acrylonitrile, or styrene.

[0060] The polymerization reaction mechanism of the (meth)acrylic adhesive resin (b) according to the present embodiment may be radical polymerization, anionic polymerization, cationic polymerization, etc. Considering the production cost of the (meth)acrylic adhesive resin (b), the effect of the functional group of the monomer, the effect of ions on the surface of the electronic component, etc., it is preferable to polymerize by radical polymerization. When polymerizing by radical polymerization reaction, the following radical polymerization initiators are used: benzoyl peroxide, di-t-butyl peroxide, dicumyl peroxide, 3,3,5-trimethylhexanoyl peroxide, di-2-ethylhexyl peroxydicarbonate, methyl ethyl ketone peroxide, t-butyl peroxyphthalate, t-butyl peroxybenzoate, di-t-butyl peroxyacetate, t-butyl peroxyisobutyrate, t-butyl peroxy-2-hexanoate, t-butyl peroxy Examples of the peroxides include organic peroxides such as 2-ethylhexanoate, t-butylperoxy-3,5,5-trimethylhexanoate, acetyl peroxide, isobutyryl peroxide, octanoyl peroxide, t-butyl peroxide, and di-t-amyl peroxide; inorganic peroxides such as ammonium persulfate, potassium persulfate, and sodium persulfate; and azo compounds such as 2,2'-azobisisobutyronitrile, 2,2'-azobis-2-methylbutyronitrile, and 4,4'-azobis-4-cyanovaleric acid.

[0061] When polymerization is performed by emulsion polymerization, among these radical polymerization initiators, preferred are inorganic peroxides such as water-soluble ammonium persulfate, potassium persulfate, and sodium persulfate, and azo compounds having a carboxyl group in the molecule such as water-soluble 4,4'-azobis-4-cyanovaleric acid. Considering the influence of ions on the surface of electronic components, azo compounds having a carboxyl group in the molecule such as ammonium persulfate and 4,4'-azobis-4-cyanovaleric acid are more preferred, and azo compounds having a carboxyl group in the molecule such as 4,4'-azobis-4-cyanovaleric acid are even more preferred.

[0062] The adhesive resin layer (B) 50 according to this embodiment preferably further contains, in addition to the adhesive resin (B1), a crosslinking agent (B2) having two or more crosslinkable functional groups in one molecule. The crosslinking agent (B2) having two or more crosslinkable functional groups in one molecule is used to react with the functional groups of the adhesive resin (B1) to adjust the adhesive strength and cohesive strength. Examples of such crosslinking agents (B2) include epoxy compounds such as sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, glycerol polyglycidyl ether, neopentyl glycol diglycidyl ether, and resorcin diglycidyl ether; isocyanate compounds such as tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate triadduct of trimethylolpropane, polyisocyanate, diphenylmethane diisocyanate, and tolylene diisocyanate; and trimethylolpropane-tri-β-aziridinylpropionate. aziridine-based compounds such as N,N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxamide), N,N'-hexamethylene-1,6-bis(1-aziridinecarboxamide), N,N'-toluene-2,4-bis(1-aziridinecarboxamide), and trimethylolpropane-tri-β-(2-methylaziridine)propionate; tetrafunctional epoxy-based compounds such as N,N,N',N'-tetraglycidyl-m-xylylenediamine and 1,3-bis(N,N'-diglycidylaminomethyl)cyclohexane; and melamine-based compounds such as hexamethoxymethylolmelamine. These may be used alone or in combination of two or more. Among these, it is preferable to contain one or more compounds selected from the group consisting of epoxy compounds, isocyanate compounds, and aziridine compounds.

[0063] The content of the crosslinking agent (B2) is usually preferably within a range in which the number of functional groups in the crosslinking agent (B2) is not greater than the number of functional groups in the adhesive resin (B1). However, if necessary, an excess of the crosslinking agent (B2) may be contained when new functional groups are generated by the crosslinking reaction or when the crosslinking reaction is slow. The content of the crosslinking agent (B2) in the adhesive resin layer (B) 50 is preferably 0.1 to 10 parts by mass, more preferably 0.5 to 5 parts by mass, per 100 parts by mass of the adhesive resin (B1).

[0064] The adhesive resin layer (B) 50 according to the present embodiment preferably contains a tackifier resin in addition to the adhesive resin (B1) from the viewpoint of improving adhesion to the support substrate. It is preferable to include a tackifier resin in the adhesive resin layer (B) 50 because it is easy to adjust the adhesion to the support substrate at around room temperature. The tackifier resin is preferably one whose softening point is 100°C or higher. Specific examples of the tackifier resin include rosin-based resins such as rosin-based derivatives treated by esterification or the like; terpene-based resins such as α-pinene-based, β-pinene-based, dipentene-based, and terpene phenol-based resins; natural rosins such as gum-based, wood-based, and tall oil-based resins; hydrogenated, disproportionated, dimerized (polymerized), or maleated resins of these natural rosins; petroleum resins; and coumarone-indene resins.

[0065] Among these, those having a softening point in the range of 100 to 160° C. are more preferred, and those having a softening point in the range of 120 to 150° C. are even more preferred. By using a tackifier resin having a softening point in the above range, not only is contamination and adhesive residue on the support substrate reduced, but the adhesion to the support substrate in the working environment can be further improved. Furthermore, by using a polymerized rosin ester-based tackifier resin as the tackifier resin, not only is contamination and adhesive residue on the support substrate reduced, but the adhesion to the support substrate in an environment of 80 to 130° C. is improved, and in the case of a heat-expandable pressure-sensitive adhesive containing heat-expandable microspheres, the heat-expandable microspheres can be more easily peeled off from the support substrate after expansion.

[0066] The blending ratio of the tackifier resin is not particularly limited, and may be appropriately selected so that the elastic modulus of the adhesive resin layer (B) 50 can be adjusted within a desired predetermined numerical range. However, in terms of the elastic modulus and initial peeling force of the adhesive resin layer (B) 50, it is preferable to set the blending ratio to 1 to 100 parts by mass of the adhesive resin (B1) to 100 parts by mass. When the blending ratio of the tackifier resin is equal to or more than the above lower limit value relative to 100 parts by mass of the adhesive resin (B1), the adhesion to the support substrate during operation tends to be good. On the other hand, when it is equal to or less than the above upper limit value, the attachment to the support substrate at room temperature tends to be good. In terms of the adhesion to the support substrate and the attachment at room temperature, it is more preferable to set the blending ratio of the tackifier resin to 2 to 50 parts by mass relative to 100 parts by mass of the adhesive resin (B1). In addition, the acid value of the tackifier resin is preferably 30 or less. When the acid value of the tackifier resin is equal to or less than the above upper limit value, adhesive residue tends to be less likely to be left on the support substrate during peeling.

[0067] The adhesive resin layer (B) 50 may contain additives such as plasticizers as other components. The total content of the adhesive resin (B1), crosslinking agent (B2) and tackifier resin in the adhesive resin layer (B) 50 is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 90% by mass or more, and even more preferably 95% by mass or more, when the entire adhesive resin layer (B) 50 is taken as 100% by mass. Furthermore, when the adhesive resin layer (B) 50 is composed of a heat-expandable adhesive, the total content of the adhesive resin (B1), crosslinking agent (B2), tackifier resin, gas-generating component and heat-expandable microspheres in the adhesive resin layer (B) 50 is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 90% by mass or more, and even more preferably 95% by mass or more, when the entire adhesive resin layer (B) 50 is taken as 100% by mass.

[0068] The thickness of the adhesive resin layer (B) 50 is preferably 5 μm or more, more preferably 20 μm or more, and is preferably 300 μm or less, more preferably 150 μm or less.

[0069] <Adhesive resin layer (A)> The laminate 100 preferably further comprises an adhesive resin layer (A), which is located between the epoxy resin layer 10 and the base material layer 40 . By providing the adhesive resin layer (A), the adhesion between the epoxy resin layer 10 and the base layer 40 can be improved, so that misalignment of the epoxy resin layer 10 can be suppressed during the process of sealing the electronic components with a sealing material, and as a result, misalignment of the electronic components can be further suppressed.

[0070] The adhesive resin layer (A) contains an adhesive resin (A1). The adhesive resin (A1) preferably contains at least one or more types selected from the group consisting of (meth)acrylic adhesive resin (a), silicone-based adhesive resin, urethane-based adhesive resin, olefin-based adhesive resin, and styrene-based adhesive resin, and among these, it is more preferable to contain (meth)acrylic adhesive resin (a) from the viewpoint of easily adjusting the adhesive strength.

[0071] The adhesive resin layer (A) may be a radiation-crosslinked adhesive resin layer whose adhesive strength is reduced by radiation. The radiation-crosslinked adhesive resin layer is crosslinked by irradiation with radiation, and its adhesive strength is significantly reduced, so that the adhesive resin layer (A) can be easily peeled off from the epoxy resin layer 10. Examples of the radiation include ultraviolet rays, electron beams, and infrared rays. The radiation crosslinkable adhesive resin layer is preferably an ultraviolet crosslinkable adhesive resin layer.

[0072] The (meth)acrylic adhesive resin (a) used in the adhesive resin layer (A) may be, for example, a copolymer containing a (meth)acrylic acid alkyl ester monomer unit (a1) and a monomer unit (a2) having a functional group capable of reacting with a crosslinking agent. In this embodiment, the (meth)acrylic acid alkyl ester means an acrylic acid alkyl ester, a methacrylic acid alkyl ester, or a mixture thereof.

[0073] The (meth)acrylic adhesive resin (a) according to this embodiment can be obtained, for example, by copolymerizing a monomer mixture containing a (meth)acrylic acid alkyl ester monomer (a1) and a monomer (a2) having a functional group capable of reacting with a crosslinking agent.

[0074] Examples of the monomer (a1) forming the (meth)acrylic acid alkyl ester monomer unit (a1) include (meth)acrylic acid alkyl esters having an alkyl group with about 1 to 12 carbon atoms. Preferred are (meth)acrylic acid alkyl esters having an alkyl group with 1 to 8 carbon atoms. Specific examples include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, and 2-ethylhexyl methacrylate. These may be used alone or in combination of two or more. In the (meth)acrylic adhesive resin (a) according to this embodiment, the content of the (meth)acrylic acid alkyl ester monomer unit (a1) is preferably from 10 mass% to 98.9 mass%, more preferably from 50 mass% to 97 mass%, and even more preferably from 85 mass% to 95 mass%, when the sum of all monomer units in the (meth)acrylic adhesive resin (a) is 100 mass%.

[0075] Examples of the monomer (a2) that forms the monomer unit (a2) having a functional group that can react with a crosslinking agent include acrylic acid, methacrylic acid, itaconic acid, mesaconic acid, citraconic acid, fumaric acid, maleic acid, itaconic acid monoalkyl ester, mesaconic acid monoalkyl ester, citraconic acid monoalkyl ester, fumaric acid monoalkyl ester, maleic acid monoalkyl ester, acrylate, methacrylate, 2-hydroxyethyl acrylate, methacrylate, acrylamide, methacrylamide, tertiary butylaminoethyl acrylate, tertiary butylaminoethyl methacrylate, etc. Preferred are acrylic acid, methacrylic acid, acrylate, 2-hydroxyethyl acrylate, methacrylate, acrylamide, methacrylamide, etc. These may be used alone or in combination of two or more. In the (meth)acrylic adhesive resin (a) according to this embodiment, the content of the monomer unit (a2) is preferably from 1 to 40% by mass, more preferably from 1 to 20% by mass, and even more preferably from 1 to 10% by mass, when the sum of all monomer units in the (meth)acrylic adhesive resin (a) is taken as 100% by mass.

[0076] The (meth)acrylic adhesive resin (a) according to this embodiment may further contain, in addition to the monomer unit (a1) and the monomer unit (a2), a bifunctional monomer unit (a3) ​​or a specific comonomer unit having surfactant properties (hereinafter referred to as a polymerizable surfactant). The polymerizable surfactant has the property of copolymerizing with the monomers (a1), (a2) and (a3), and also acts as an emulsifier in the case of emulsion polymerization.

[0077] Examples of the monomer (a3) ​​forming the bifunctional monomer unit (a3) ​​include allyl methacrylate, allyl acrylate, divinylbenzene, vinyl methacrylate, vinyl acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tetraethylene glycol di(meth)acrylate, and, for example, those having diacrylate or dimethacrylate at both ends and a main chain structure of propylene glycol type (e.g., Nippon Oil & Fats Corporation, trade names: PDP-200, PDP-400, ADP-200, ADP-400), tetramethylene glycol type (e.g., Nippon Oil & Fats Corporation, trade names: ADT-250, ADT-850) and mixtures thereof (e.g., Nippon Oil & Fats Corporation, trade names: ADET-1800, ADPT-4000).

[0078] In the (meth)acrylic adhesive resin (a) according to this embodiment, the content of the monomer unit (a3) ​​is preferably from 0.1 to 30% by mass, more preferably from 0.1 to 20% by mass, even more preferably from 0.1 to 15% by mass, and even more preferably from 0.1 to 5% by mass, when the sum of all monomer units in the (meth)acrylic adhesive resin (a) is 100% by mass.

[0079] Examples of polymerizable surfactants include those in which a polymerizable 1-propenyl group has been introduced into the benzene ring of polyoxyethylene nonylphenyl ether (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.; trade names: Aqualon RN-10, RN-20, RN-30, RN-50, etc.), those in which a polymerizable 1-propenyl group has been introduced into the benzene ring of an ammonium salt of a sulfate ester of polyoxyethylene nonylphenyl ether (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.; trade names: Aqualon HS-10, HS-20, HS-1025, etc.), and sulfosuccinic acid diesters having a polymerizable double bond in the molecule (manufactured by Kao Corporation; trade names: Latemul S-120A, S-180A, etc.). In the (meth)acrylic adhesive resin (a) according to this embodiment, the content of the polymerizable surfactant is preferably from 0.1% by mass to 30% by mass, more preferably from 0.1% by mass to 20% by mass, even more preferably from 0.1% by mass to 15% by mass, and even more preferably from 0.1% by mass to 5% by mass, when the sum of all monomer units in the (meth)acrylic adhesive resin (a) is taken as 100% by mass.

[0080] The (meth)acrylic adhesive resin (a) according to this embodiment may further contain, if necessary, a monomer unit formed from a monomer having a polymerizable double bond, such as vinyl acetate, acrylonitrile, or styrene.

[0081] The polymerization reaction mechanism of the (meth)acrylic adhesive resin (a) according to the present embodiment may be radical polymerization, anionic polymerization, cationic polymerization, etc. Considering the production cost of the (meth)acrylic adhesive resin (a), the effect of the functional group of the monomer, the effect of ions on the surface of the electronic component, etc., it is preferable to polymerize by radical polymerization. When polymerizing by radical polymerization reaction, the following radical polymerization initiators are used: benzoyl peroxide, di-t-butyl peroxide, dicumyl peroxide, 3,3,5-trimethylhexanoyl peroxide, di-2-ethylhexyl peroxydicarbonate, methyl ethyl ketone peroxide, t-butyl peroxyphthalate, t-butyl peroxybenzoate, di-t-butyl peroxyacetate, t-butyl peroxyisobutyrate, t-butyl peroxy-2-hexanoate, t-butyl peroxy Examples of the peroxides include organic peroxides such as 2-ethylhexanoate, t-butylperoxy-3,5,5-trimethylhexanoate, acetyl peroxide, isobutyryl peroxide, octanoyl peroxide, t-butyl peroxide, and di-t-amyl peroxide; inorganic peroxides such as ammonium persulfate, potassium persulfate, and sodium persulfate; and azo compounds such as 2,2'-azobisisobutyronitrile, 2,2'-azobis-2-methylbutyronitrile, and 4,4'-azobis-4-cyanovaleric acid.

[0082] When polymerization is performed by emulsion polymerization, among these radical polymerization initiators, preferred are inorganic peroxides such as water-soluble ammonium persulfate, potassium persulfate, and sodium persulfate, and azo compounds having a carboxyl group in the molecule such as water-soluble 4,4'-azobis-4-cyanovaleric acid. Considering the influence of ions on the surface of electronic components, azo compounds having a carboxyl group in the molecule such as ammonium persulfate and 4,4'-azobis-4-cyanovaleric acid are more preferred, and azo compounds having a carboxyl group in the molecule such as 4,4'-azobis-4-cyanovaleric acid are even more preferred.

[0083] The adhesive resin layer (A) according to this embodiment preferably further contains, in addition to the adhesive resin (A1), a crosslinking agent (A2) having two or more crosslinkable functional groups in one molecule. The crosslinking agent (A2) having two or more crosslinkable functional groups in one molecule is used to react with the functional groups of the adhesive resin (A1) to adjust the adhesive strength and cohesive strength. Examples of such crosslinking agents (A2) include epoxy compounds such as sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, glycerol polyglycidyl ether, neopentyl glycol diglycidyl ether, and resorcin diglycidyl ether; isocyanate compounds such as tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate triadduct of trimethylolpropane, polyisocyanate, diphenylmethane diisocyanate, and tolylene diisocyanate; and trimethylolpropane-tri-β-aziridinylpropionate. aziridine-based compounds such as N,N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxamide), N,N'-hexamethylene-1,6-bis(1-aziridinecarboxamide), N,N'-toluene-2,4-bis(1-aziridinecarboxamide), and trimethylolpropane-tri-β-(2-methylaziridine)propionate; tetrafunctional epoxy-based compounds such as N,N,N',N'-tetraglycidyl-m-xylylenediamine and 1,3-bis(N,N'-diglycidylaminomethyl)cyclohexane; and melamine-based compounds such as hexamethoxymethylolmelamine. These may be used alone or in combination of two or more. Among these, it is preferable to contain one or more compounds selected from the group consisting of epoxy compounds, isocyanate compounds, and aziridine compounds.

[0084] The content of the crosslinking agent (A2) is usually preferably within a range in which the number of functional groups in the crosslinking agent (A2) is not greater than the number of functional groups in the adhesive resin (A1). However, if necessary, an excess of the crosslinking agent (A2) may be contained when new functional groups are generated by the crosslinking reaction or when the crosslinking reaction is slow. The content of the crosslinking agent (A2) in the adhesive resin layer (A) is preferably 0.1 parts by mass or more and 15 parts by mass or less per 100 parts by mass of the adhesive resin (A1), from the viewpoint of improving the balance between the heat resistance and adhesion of the adhesive resin layer (A).

[0085] The adhesive resin layer (A) may contain additives such as plasticizers and tackifier resins as other components. When the adhesive resin layer (A) is a radiation crosslinking adhesive resin layer, it may contain various additives for radiation crosslinking. The total content of the adhesive resin (A1) and the crosslinking agent (A2) in the adhesive resin layer (A) is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 90% by mass or more, and even more preferably 95% by mass or more, when the entire adhesive resin layer (A) is taken as 100% by mass. This makes it easier to obtain the structure (b) described below.

[0086] The total content of the gas-generating component and the heat-expandable microspheres in the adhesive resin layer (A) is preferably less than 0.1% by mass, more preferably less than 0.05% by mass, even more preferably less than 0.01% by mass, and even more preferably 0.00% by mass, based on 100% by mass of the entire adhesive resin layer (A). Here, the gas-generating component and the heat-expandable microspheres mentioned above refer to the same components as the gas-generating component and the heat-expandable microspheres contained in the adhesive resin layer (B) 50 .

[0087] The thickness of the adhesive resin layer (A) is preferably 1 μm or more, more preferably 3 μm or more, and is preferably 100 μm or less, more preferably 50 μm or less.

[0088] <Other layers> The laminate 100 may be provided with other components as long as the effects of this embodiment are not impaired. As other layers, an unevenness absorbing layer, an impact absorbing layer, an easy-adhesion layer, etc. may be further provided. The other layers are located, for example, between the epoxy resin layer 10 and the base layer 40; between the base layer 40 and the adhesive resin layer (B) 50; between the adhesive resin layer (A) and the base layer 40; and the like.

[0089] The unevenness-absorbing layer is preferably formed from natural rubber or synthetic rubber, or synthetic resin having rubber elasticity, having a Shore D hardness of, for example, 50 or less, preferably 40 or less according to Shore D hardness of ASTM D-2240. The thickness of the unevenness-absorbing layer is, for example, 500 μm or less, preferably 5 to 300 μm, more preferably 10 to 150 μm.

[0090] Examples of synthetic rubber or synthetic resin include synthetic rubbers such as nitrile, diene, and acrylic, thermoplastic elastomers such as polyolefin and polyester, and synthetic resins having rubber elasticity such as ethylene-vinyl acetate copolymer, polyurethane, polybutadiene, and soft polyvinyl chloride. In this embodiment, even if the polymer is essentially hard, such as polyvinyl chloride, it can be used that has rubber elasticity due to the combination with a compounding agent such as a plasticizer or softener. In addition, the adhesive resins exemplified in the above-mentioned adhesive resin layer (A) and adhesive resin layer (B) 50 can also be preferably used to form the unevenness absorbing layer.

[0091] [Method of manufacturing temporary fixing material] The method for producing the temporary fixing material of the present embodiment is not particularly limited, but for example, the following method can be mentioned. When the temporary fixing material of the present embodiment is a film set including an epoxy film including an epoxy resin layer 10 and an adhesive film including a base layer 40 and an adhesive resin layer (B) 50, for example, an epoxy film can be obtained by applying a resin composition for forming the epoxy resin layer 10 onto the base film and drying it. Also, for example, an adhesive film can be obtained by applying an adhesive coating liquid for forming the adhesive resin layer (B) 50 onto the base layer 40 and drying it. When the temporary fixing material of this embodiment is a laminated film having an epoxy resin layer 10, a base material layer 40, and an adhesive resin layer (B) 50 in this order, for example, a laminated film can be obtained by bonding the base material layer 40 of the adhesive film and the epoxy resin layer 10 of the epoxy film.

[0092] [Electronic device manufacturing method] A preferred embodiment of the method for producing an electronic device according to the present embodiment will be described with reference to FIGS.

[0093] The electronic device in this embodiment includes elements, devices, final products, etc. to which electronic engineering technology is applied, such as semiconductor devices, power semiconductor devices, semiconductor chips, semiconductor elements, printed wiring boards, electric circuit display devices, information and communication terminals, light-emitting diodes, physical batteries, and chemical batteries. The electronic device of this embodiment preferably includes a fan-out type package. In a fan-out type package, terminals can be spread out to the outside of the chip (fan out), so it can be used in applications where the number of terminals is large compared to the chip area. In addition, since a package substrate is not required, it can be made thinner.

[0094] Each step of a preferred embodiment of the method for producing an electronic device according to the present embodiment will be described below.

[0095] <Step (A) of preparing a structure (a)> The manufacturing method for the electronic device of this embodiment preferably includes a step (A) of preparing a structure (a) 200 including a laminate 100 including an epoxy resin layer 10, a base material layer 40, and an adhesive resin layer (B) 50 in this order, an electronic component 70 fixed to the epoxy resin layer 10, and a support substrate 80 attached to the adhesive resin layer (B) 50.

[0096] The method for preparing the structure (a) 200 is not particularly limited, but preferably includes a step (A-1) of preparing a structure (a-1) having a base layer 40, an adhesive resin layer (B) 50, and a support substrate 80 attached to the adhesive resin layer (B) 50, and a step (A-2) of preparing a structure (a-2) in which an epoxy resin layer 10 is attached to the surface of the structure (a-1) opposite to the support substrate 80 side. 1, the surface opposite to the support substrate 80 side is the base layer 40. In addition, for example, when the structure (a-1) further includes an adhesive resin layer (A) on the surface of the base layer 40 opposite to the adhesive resin layer (B) 50 side, the surface opposite to the support substrate 80 side is the adhesive resin layer (A).

[0097] In the step (A-1), the structure (a-1) can be prepared, for example, by the following procedure. A structure (a-1) is obtained by laminating an adhesive film including a base layer 40 and an adhesive resin layer (B) 50 on a support substrate 80 so that the adhesive resin layer (B) 50 side faces the support substrate 80. When a protective film is attached on the adhesive resin layer (B) 50 in the adhesive film, the protective film can be peeled off and the exposed surface of the adhesive resin layer (B) 50 can be attached to the surface of the support substrate 80.

[0098] In the step (A-2), the structure (a-2) can be prepared, for example, by the following procedure. A structure (a-2) is obtained by laminating an epoxy film containing an epoxy resin layer 10 onto the base layer 40 in the structure (a-1) so that the epoxy resin layer 10 side faces the base layer 40. When the epoxy film contains a base film, a protective film, etc., the base film, the protective film, etc. may be removed as appropriate.

[0099] In addition to steps (A-1) and (A-2), it is preferable that step (A) of preparing structure (a) 200 further includes step (A-3) of adhering electronic component 70 to epoxy resin layer 10 of structure (a-2) to prepare structure (a) 200.

[0100] In the step (A), from the viewpoint of further improving the attachment property, the epoxy resin layer 10 is preferably in an uncured state or a semi-cured state.

[0101] In the step (A), the epoxy resin layer 10 may be in a cured state. When the epoxy resin layer 10 is in a cured state, the epoxy resin layer 10 can be made into the insulating resin layer 20 described below.

[0102] The support substrate 80 may be, for example, a quartz substrate, a glass substrate, or a SUS substrate.

[0103] Examples of the electronic component 70 include semiconductor chips such as ICs, LSIs, discrete devices, light-emitting diodes, and light-receiving elements, semiconductor panels, and semiconductor packages.

[0104] <Step (B) of curing the epoxy resin layer> The method for manufacturing an electronic device according to the present embodiment preferably includes a step (B) of curing the epoxy resin layer 10. By curing the epoxy resin layer 10, the insulating resin layer 20 is formed. Step (B) is carried out between steps (A) and (C).

[0105] The method for curing the epoxy resin layer 10 is not particularly limited, and may be heat curing or photocuring, but heat curing is preferred.

[0106] The curing temperature when the epoxy resin layer 10 is thermally cured is not particularly limited, but may be, for example, 120°C or more, 140°C or more, 150°C or more, 170°C or more, and may be 240°C or less, 220°C or less, or 200°C or less. The curing time when the epoxy resin layer 10 is thermally cured is not particularly limited, but is, for example, 5 minutes or more and 120 minutes or less.

[0107] When the epoxy resin layer 10 is thermally cured, the epoxy resin layer 10 may be preheated at a temperature lower than the curing temperature before being thermally cured.

[0108] <Process (C) of sealing electronic components> The method for manufacturing an electronic device according to the present embodiment preferably includes a step (C) of encapsulating electronic components 70 with encapsulant 60 . The electronic components 70 are covered with the sealing material 60, and the sealing material 60 is cured at a temperature of, for example, 150° C. or less to seal the electronic components 70. The form of the sealing material 60 is not particularly limited, but may be, for example, granular, sheet-like, or liquid.

[0109] In step (C), it is preferable that electronic components 70 are fixed to insulating resin layer 20, since this makes it possible to prevent the electronic components from being displaced.

[0110] The sealing material 60 is not particularly limited, but is preferably an epoxy resin-based sealing material using an epoxy resin. In particular, a liquid epoxy resin-based sealing material is preferred because it provides better affinity of the sealing material 60 to the epoxy resin layer 10 and enables the electronic components 70 to be sealed more evenly. As such an epoxy resin-based sealing material, for example, T693 / R4000 series, T693 / R1000 series, T693 / R5000 series, etc. manufactured by Nagase ChemteX Corporation can be used.

[0111] Examples of the sealing method include transfer molding, injection molding, compression molding, cast molding, and the like.

[0112] <Step (D) of Obtaining Structure (b)> The manufacturing method for the electronic device of this embodiment preferably includes a step (D) of obtaining a structure (b) 300 including an insulating resin layer 20 formed by curing an epoxy resin layer 10, and an electronic component 70 adhered to the insulating resin layer 20 and sealed with a sealing material 60. Step (D) is a step subsequent to step (C).

[0113] The structure (b) 300 includes an insulating resin layer 20 formed by curing the epoxy resin layer 10 in the temporary fixing material of this embodiment. As described above, the method for manufacturing an electronic device according to the present embodiment does not include a step of peeling off the insulating resin layer 20 from the electronic component 70, and therefore it is possible to prevent adhesive residue from being left on the electronic component side.

[0114] The method for obtaining the structure (b) 300 is not particularly limited, but examples thereof include a method of mechanically peeling off the insulating resin layer 20 from a layer adjacent to the insulating resin layer 20 (in the case of Figure 1, the base material layer 40); a method of reducing the adhesive force between the insulating resin layer 20 and the layer adjacent to the insulating resin layer 20 and then peeling off the insulating resin layer 20 from the layer adjacent to the insulating resin layer 20; and the like.

[0115] As a method for obtaining the structure (b) 300, the adhesive resin layer (B) 50 may be peeled off from the support substrate 80 before peeling off the insulating resin layer 20 and the layer adjacent to the insulating resin layer 20. A method for peeling off the adhesive resin layer (B) 50 from the support substrate 80 includes, for example, heating to a temperature exceeding 170°C to reduce the adhesive strength of the adhesive resin layer (B) 50, thereby peeling off the adhesive resin layer (B) 50 from the support substrate 80.

[0116] <Step (E) of forming a rewiring layer> The method for manufacturing an electronic device according to the present embodiment preferably includes a step (E) of forming wiring in the insulating resin layer 20 to form a rewiring layer 30. Step (E) is a step subsequent to step (D).

[0117] The rewiring layer 30 can be obtained by forming wiring in the insulating resin layer 20 . The method for forming wiring in the insulating resin layer 20 is not particularly limited, but for example, a method in which a pattern mold is made from a photoresist and wiring is formed by electrolytic plating can be mentioned.

[0118] <Step (F) of Further Forming a Rewiring Layer> The method for manufacturing an electronic device of this embodiment preferably further includes the step (F) of forming a redistribution layer 90 . Step (F) is a step subsequent to step (E).

[0119] The rewiring layer 90 is preferably formed on the surface of the rewiring layer 30 opposite to the electronic component 70 side. The method for forming the rewiring layer 90 is not particularly limited, but an example of such a method includes forming an epoxy resin layer of the same type as the epoxy resin layer 10 of this embodiment, and forming wiring on the insulating resin layer obtained by hardening the epoxy resin layer.

[0120] Moreover, a further redistribution layer may be formed on the surface of the redistribution layer 90 opposite to the redistribution layer 30 side, thereby forming a plurality of redistribution layers.

[0121] <Other processes> The method for manufacturing an electronic device according to this embodiment may further include a post-mold cure step, a dicing step, and the like.

[0122] Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various configurations other than those described above can also be adopted.

[0123] The present invention is not limited to the above-described embodiment, and modifications and improvements within the scope of the present invention that can achieve the object of the present invention are included in the present invention. [Explanation of symbols]

[0124] 10 Epoxy resin layer 20 Insulating resin layer 30 Redistribution layer 40 Base material layer 50 Adhesive resin layer (B) 60 Encapsulating material 70 Electronic Components 80 Support substrate 90 Redistribution layer 100 Laminate 200 Structure (a) 300 Structure (b)

Claims

1. A temporary fixing material capable of temporarily fixing an electronic component when sealing the electronic component with a sealing material in a manufacturing process of an electronic device, In a step prior to the step of sealing the electronic component with a sealing material, a laminate is formed which includes, in this order, an epoxy resin layer to which the electronic component can be fixed, a base layer, and an adhesive resin layer (B) to be attached to a support substrate; a content of the epoxy resin in the epoxy resin layer being 10 parts by mass or more when a total content of resin components in the epoxy resin layer is 100 parts by mass;

2. The temporary fixing material according to claim 1 , wherein the epoxy resin layer is in an uncured state or a semi-cured state.

3. The temporary fixing material according to claim 1 or 2, wherein the epoxy resin layer further contains an inorganic filler.

4. The temporary fixing material according to claim 1 or 2, wherein the epoxy resin layer further contains a curing agent.

5. The temporary fixing material according to claim 1 , wherein the insulating resin layer formed by curing the epoxy resin layer is capable of forming a rewiring layer.

6. The temporary fixing material according to claim 1 or 2, wherein the adhesive strength of the adhesive resin layer (B) decreases in response to an external stimulus.

7. The temporary fixing material according to claim 6 , wherein the adhesive strength of the adhesive resin layer (B) decreases when heated.

8. The temporary fixing material according to claim 7 , wherein the adhesive resin layer (B) contains at least one selected from the group consisting of a gas-generating component and heat-expandable microspheres.

9. The laminate further includes an adhesive resin layer (A), The temporary fixing material according to claim 1 or 2, wherein the adhesive resin layer (A) is located between the epoxy resin layer and the base material layer.

10. 10. The temporary fixing material according to claim 9, wherein the total content of the gas-generating component and the heat-expandable microspheres in the adhesive resin layer (A) is less than 0.1% by mass, when the entire adhesive resin layer (A) is taken as 100% by mass.

11. 10. The temporary fixing material according to claim 9, wherein the adhesive resin layer (A) contains one or more selected from the group consisting of (meth)acrylic adhesive resins, silicone adhesive resins, urethane adhesive resins, olefin adhesive resins, and styrene adhesive resins.

12. The temporary fixing material according to claim 1 or 2, wherein the sealing material includes an epoxy resin-based sealing material.

13. The temporary fixing material according to claim 1 or 2, wherein the electronic device includes a fan-out type package.

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