Method for manufacturing electronic device

Abstract

Provided is a method for manufacturing an electronic device, the method comprising, in the following order: a step for preparing an adhesive film (50) including an adhesive resin layer (B), a base material layer (A), and an adhesive resin layer (C) in this order, and then affixing a support substrate (80) to the adhesive resin layer (C) side of the adhesive film (50); a step for reducing the amount of volatile components in the adhesive film (50); a step for affixing electronic components (70) to the adhesive resin layer (B) side of the adhesive film (50); and a step for sealing the electronic components (70) with a sealing material (60). At least one selected from the adhesive resin layer (B) and the adhesive resin layer (C) includes a layer in which the adhesive force decreases due to an external stimulus.

Description

Method of manufacturing electronic devices

[0001] This invention relates to a method for manufacturing an electronic device.

[0002] Fan-out packaging is a well-known technology that can miniaturize and lighten electronic devices (e.g., semiconductor devices). One method for manufacturing fan-out packaging is eWLB (Embedded Wafer Level Ball Grid Array), in which multiple electronic components such as semiconductor chips are temporarily fixed at intervals on an adhesive film attached to a support substrate, and the multiple electronic components are sealed together with a sealing material. Here, the adhesive film needs to be fixed to the electronic components and support substrate during the sealing process, and after sealing, it needs to be removed from the sealed electronic components along with the support substrate.

[0003] Examples of technologies related to the manufacturing method of such fan-out type packages include those described in Patent Document 1 (Japanese Patent Application Publication No. 2011-134811).

[0004] Patent Document 1 describes a heat-resistant adhesive sheet for semiconductor device manufacturing, which is used when resin-encapsulating a substrate-less semiconductor chip. The purpose of this invention is to solve the problems of the chip not being held in place by the pressure during resin encapsulation and shifting from the designated position, or the package being damaged when peeling off the heat-resistant adhesive sheet for semiconductor device manufacturing due to the hardening of the encapsulating material or the strong adhesion to the chip surface due to heat. The heat-resistant adhesive sheet comprises a base layer and an adhesive layer, and the adhesive layer has an adhesive strength to SUS304 after bonding of 0.5 N / 20 mm or more, and hardens due to the stimuli received by the time the resin encapsulation process is completed, resulting in a package peeling strength of 2.0 N / 20 mm or less.

[0005] Japanese Patent Publication No. 2011-134811

[0006] According to the inventors' research, when arranging electronic components having an uneven structure, such as bumps, on an adhesive film and sealing the electronic components with a sealing material, it has become clear that lifting may occur between the support substrate used to fix the adhesive film and the adhesive film, resulting in sealing failure. The present invention provides a method for manufacturing an electronic device that can suppress the occurrence of lifting between the support substrate and the adhesive film.

[0007] The inventors diligently conducted research to achieve the above objectives. As a result, they discovered that by reducing the amount of volatile components in the adhesive film after bonding the support substrate and the adhesive film, the occurrence of lifting between the support substrate and the adhesive film can be suppressed, thus completing the present invention.

[0008] According to the present invention, a method for manufacturing the following electronic device is provided.

[0009] [1] A method for manufacturing an electronic device, comprising the steps of: preparing an adhesive film containing an adhesive resin layer (B), a substrate layer (A), and an adhesive resin layer (C) in that order; then attaching a support substrate to the adhesive resin layer (C) side of the adhesive film; reducing the amount of volatile components in the adhesive film; attaching an electronic component to the adhesive resin layer (B) side of the adhesive film; and sealing the electronic component with a sealing material, wherein at least one of the adhesive resin layer (B) and the adhesive resin layer (C) is a layer whose adhesive strength decreases due to external stimuli. [2] The method for manufacturing an electronic device according to [1], wherein the electronic component includes a semiconductor chip. [3] The area of ​​the upper surface of the electronic component is 10 mm ２ 500mm or more ２The method for manufacturing an electronic device as described in [1] or [2] above, wherein: [4] The method for manufacturing an electronic device as described in any of [1] to [3] above, wherein the average distance between a plurality of the above electronic components is 1500 μm or less. [5] The method for manufacturing an electronic device as described in any of [1] to [4] above, wherein the above electronic components are rectangular and the coverage rate according to the following formula (1) is 80% or more. Coverage rate (%) = 100 × [(vertical length of one of the above electronic components) × (horizontal length of one of the above electronic components) × (number of electronic components)] / {[(vertical length of one of the above electronic components) + (average distance between the above electronic components)] × [(horizontal length of one of the above electronic components) + (average distance between the above electronic components)] × (number of electronic components)} ... Formula (1) [6] The method for manufacturing an electronic device as described in any of [1] to [5] above, wherein the step of reducing the amount of volatile components in the adhesive film includes a step of reducing the amount of volatile components in the adhesive film by heat treatment. [7] The method for manufacturing an electronic device according to [6], wherein the heating time in the step of reducing the amount of volatile components in the adhesive film by the heat treatment is 0.1 hours or more and 48 hours or less. [8] The method for manufacturing an electronic device according to [6] or [7], wherein the heating temperature in the step of reducing the amount of volatile components in the adhesive film by the heat treatment is 100°C or more and 150°C or less. [9] The method for manufacturing an electronic device according to any one of [1] to [8], further comprising a step of reducing the adhesive force of at least one selected from the adhesive resin layer (B) and the adhesive resin layer (C) by external stimulation.

[10] The method for manufacturing an electronic device according to any one of [1] to [9], wherein the sealing material includes an epoxy resin sealing material.

[11] The method for manufacturing an electronic device according to any one of [1] to

[10] , wherein at least one selected from the adhesive resin layer (B) and the adhesive resin layer (C) includes one or more selected from the group consisting of a heat-peelable adhesive resin layer and a light-peelable adhesive resin layer.

[12] The method for manufacturing an electronic device according to

[11] , wherein the heat-peelable adhesive resin layer includes an adhesive resin layer whose adhesive strength decreases or is lost when heated at a temperature exceeding 100°C.

[13] The method for manufacturing an electronic device according to any one of [1] to

[12] above, wherein the adhesive resin (C1) constituting the adhesive resin layer (C) comprises one or more selected from the group consisting of (meth)acrylic adhesive resins, urethane adhesive resins, silicone adhesive resins, polyolefin adhesive resins, polyester adhesive resins, polyamide adhesive resins, fluorine adhesive resins, and styrene-diene block copolymer adhesive resins.

[14] The method for manufacturing an electronic device according to any one of [1] to

[13] above, wherein the thickness of the adhesive resin layer (C) is 1 μm or more and 500 μm or less.

[15] The method for manufacturing an electronic device according to any one of [1] to

[14] above, wherein the adhesive resin (B1) constituting the adhesive resin layer (B) comprises 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.

[16] The method for manufacturing an electronic device according to any one of [1] to

[15] , wherein the thickness of the adhesive resin layer (B) is 1 μm or more and 500 μm or less.

[17] The method for manufacturing an electronic device according to any one of [1] to

[16] , further comprising an intermediate layer (D) between the base layer (A) and the adhesive resin layer (B), and between the base layer (A) and the adhesive resin layer (C).

[18] The method for manufacturing an electronic device according to

[17] , wherein the intermediate layer (D) includes a layer that hardens upon external stimulation.

[19] The method for manufacturing an electronic device according to

[17] or

[18] , wherein the intermediate layer (D) includes a crosslinking agent.

[20] The method for manufacturing an electronic device according to

[19] , wherein the crosslinking agent includes one or more selected from the group consisting of polyfunctional (meth)acrylate compounds and isocyanate compounds.

[21] A method for manufacturing an electronic device according to any one of

[17] to

[20] , wherein the intermediate layer (D) comprises one or more selected from the group consisting of thermal initiators and photoinitiators.

[22] The method for manufacturing an electronic device according to

[21] , wherein the thermal initiator comprises one or more selected from the group consisting of aromatic ketones, onium salt compounds, organic peroxides, thio compounds, hexaarylbiimidazole compounds, ketoxime ester compounds, borate compounds, azinium compounds, metallocene compounds, active ester compounds, compounds having carbon-halogen bonds, and azo compounds.

[23] The method for manufacturing an electronic device according to

[21] or

[22] , wherein the photoinitiator comprises an alkylphenone photoinitiator.

[24] The method for manufacturing an electronic device according to any one of

[17] to

[23] , wherein the thickness of the intermediate layer (D) is 5 μm or more and 1000 μm or less.

[25] The method for manufacturing an electronic device according to any one of [1] to

[24] , wherein the substrate layer (A) comprises a thermoplastic resin.

[26] The method for manufacturing an electronic device according to any one of [1] to

[25] , wherein the thickness of the substrate layer (A) is 1 μm or more and 500 μm or less.

[27] A method for manufacturing an electronic device according to any one of [1] to

[26] above, wherein the electronic device includes a fan-out type package.

[0010] According to the present invention, it is possible to provide a method for manufacturing an electronic device that can suppress the occurrence of lifting between the support substrate and the adhesive film.

[0011] This is a schematic cross-sectional view showing an example of the structure of the adhesive film of this embodiment. This is a schematic cross-sectional view showing an example of the structure of the adhesive film of this embodiment. This is a schematic cross-sectional view showing an example of the manufacturing method of the electronic device of this embodiment. This is a schematic cross-sectional view showing an example of the manufacturing method of the electronic device of this embodiment.

[0012] <Method for Manufacturing an Electronic Device> First, the method for manufacturing an electronic device according to this embodiment will be described. Figures 1 and 2 are schematic cross-sectional views showing an example of the structure of the adhesive film 50 according to this embodiment. Figures 3 and 4 are schematic cross-sectional views showing an example of the method for manufacturing an electronic device according to this embodiment. The method for manufacturing an electronic device according to this embodiment includes, in this order, the steps of: preparing an adhesive film 50 containing an adhesive resin layer (B), a base layer (A), and an adhesive resin layer (C) in that order; then attaching a support substrate 80 to the adhesive resin layer (C) side of the adhesive film 50; reducing the amount of volatile components in the adhesive film 50; attaching an electronic component 70 to the adhesive resin layer (B) side of the adhesive film 50; and sealing the electronic component 70 with a sealing material 60, wherein at least one of the adhesive resin layer (B) and the adhesive resin layer (C) is a layer whose adhesive strength decreases due to external stimuli.

[0013] As described above, our studies have revealed that when electronic components having an uneven structure, such as bumps, are placed on an adhesive film and sealed with a sealing material, lifting may occur between the support substrate for fixing the adhesive film and the adhesive film, resulting in a sealing failure. Based on the above findings, we conducted further studies. As a result, we have discovered for the first time that lifting between the support substrate and the adhesive film can be suppressed by reducing the amount of volatile components in the adhesive film after bonding the support substrate 80 and the adhesive film together. Thus, according to this embodiment, we can provide a method for manufacturing an electronic device that can suppress the occurrence of lifting between the support substrate and the adhesive film.

[0014] The following describes each step in the manufacturing method of the electronic device according to this embodiment.

[0015] [Steps to prepare an adhesive film 50 containing an adhesive resin layer (B), a base layer (A), and an adhesive resin layer (C) in this order, and then attach a support substrate 80 to the adhesive resin layer (C) side of the adhesive film 50] First, an adhesive film 50 is prepared containing an adhesive resin layer (B), a base layer (A), and an adhesive resin layer (C) in this order, and then a support substrate 80 is attached to the adhesive resin layer (C) side of the adhesive film 50.

[0016] The adhesive film 50, which includes an adhesive resin layer (B), a base layer (A), and an adhesive resin layer (C) in this order, will be described later.

[0017] A protective film may be attached to the adhesive resin layer (C), and the protective film can be peeled off to allow the exposed surface of the adhesive resin layer (C) to be attached to the surface of the support substrate 80. For example, the support substrate 80 can be a quartz substrate, a glass substrate, a SUS substrate, etc.

[0018] [Step to reduce the amount of volatile components in the adhesive film 50] Next, the amount of volatile components in the adhesive film 50 is reduced. The step to reduce the amount of volatile components in the adhesive film 50 preferably includes a step to reduce the amount of volatile components in the adhesive film 50 by a treatment that includes one or more selected from the group consisting of heat treatment and vacuum treatment, and more preferably includes a step to reduce the amount of volatile components in the adhesive film 50 by heat treatment.

[0019] In the step of reducing the amount of volatile components in the adhesive film 50 by heat treatment, the heating time is preferably 0.1 hours to 48 hours, more preferably 0.3 hours to 24 hours, even more preferably 0.5 hours to 12 hours, even more preferably 0.6 hours to 6 hours, even more preferably 0.7 hours to 3 hours, and even more preferably 0.8 hours to 2 hours, from the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the misalignment of the electronic components 70 in the sealing step, as well as from the viewpoint of improving productivity. In this embodiment, if the adhesive film 50 includes at least one of the adhesive resin layer (B) and adhesive resin layer (C) selected from the adhesive resin layer (C), the heating temperature in the step of reducing the amount of volatile components in the adhesive film 50 is preferably below the temperature at which the adhesive strength of the layer whose adhesive strength is reduced by external stimuli decreases.

[0020] The heating temperature in the step of reducing the amount of volatile components in the adhesive film 50 by heat treatment is preferably 100°C to 150°C, more preferably 110°C to 140°C, and even more preferably 120°C to 135°C, from the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 during the sealing step. The method of heat treatment of the adhesive film 50 is not particularly limited, but generally known heat treatment methods such as ovens, dryers, heating rolls, and drying furnaces can be used.

[0021] When the adhesive film 50 is subjected to reduced pressure, the pressure during the reduced pressure is preferably 100 Pa or more and 10,000 Pa or less, from the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 during the sealing process. The method for subjecting the adhesive film 50 to reduced pressure is not particularly limited, but a generally known reduced pressure method such as a vacuum dryer can be used. The amount of volatile components can be adjusted by adjusting the conditions of the heat treatment and reduced pressure treatment, but when heat treatment is performed at a temperature exceeding 100°C, it is preferable to set the pressure during reduced pressure to 500 Pa or more in order to prevent delamination between the electronic components 70 and the adhesive film 50.

[0022] Whether the amount of volatile components in the adhesive film 50 has decreased can be determined by known methods such as thermogravimetric analysis.

[0023] [Step of attaching electronic components 70 to the adhesive resin layer (B) side of the adhesive film 50] Next, the electronic components 70 are attached to the adhesive resin layer (B) side of the adhesive film 50. In this step, the structure 100 can be obtained by arranging the electronic components 70 on the adhesive resin layer (B) of the adhesive film 50 attached to the support substrate 80. The electronic components 70 can be any known electronic components, but preferably include one or more selected from the group consisting of semiconductor chips such as ICs, LSIs, discretes, light-emitting diodes, and photodetectors, semiconductor panels, semiconductor packages, wafers, and semiconductor substrates, and more preferably include semiconductor chips.

[0024] The surface of the electronic component 70 preferably has an uneven surface. The uneven surface preferably includes electrodes such as concave electrodes or convex electrodes, and more preferably includes convex electrodes. In this case, the electrodes are, for example, joined to electrodes formed on the mounting surface when mounting the electronic device to the mounting surface, forming an electrical connection between the electronic device and the mounting surface (mounting surface such as a printed circuit board). The electrodes preferably include one or more types of bump electrodes selected from the group consisting of ball bumps, printed bumps, stud bumps, plated bumps, and pillar bumps. That is, the uneven surface of this embodiment preferably includes bump electrodes. The type of metal constituting the bump electrodes is not particularly limited, but preferably includes one or more types selected from the group consisting of silver, gold, copper, tin, lead, or bismuth and alloys thereof.

[0025] When the concavo-convex structure of this embodiment includes bump electrodes, when the height of the bump electrodes is H [μm] and the thickness of the adhesive resin layer (B) is d [μm], H / d is preferably 1 or less, more preferably 0.85 or less, and even more preferably 0.7 or less. When H / d is below the above upper limit value, while making the thickness of the adhesive film 50 thinner, the generation of floating between the support substrate 80 and the adhesive film 50 and the displacement of the electronic component 70 in the sealing process can be more effectively suppressed. The lower limit of H / d is not particularly limited, but for example, it is 0.01 or more. The height of the bump electrodes is generally 2 μm or more and 600 μm or less.

[0026] From the perspective of further suppressing the generation of floating between the support substrate 80 and the adhesive film 50 and the displacement of the electronic component 70 in the sealing process, the area of the upper surface of the electronic component 70 is preferably 10 mm ２ or more and 500 mm ２ or less, more preferably 13 mm ２ or more and 450 mm ２ or less, even more preferably 15 mm ２ or more and 400 mm ２ or less, even more preferably 18 mm ２ or more and 350 mm ２ or less, even more preferably 20 mm ２ or more and 300 mm ２ or less. Note that the area of the upper surface of the electronic component 70 refers to the area of the surface facing the surface adhered to the adhesive film 50 when the electronic component 70 is attached to the adhesive film 50.

[0027] When multiple electronic components 70 are attached to the adhesive film 50, the average spacing between the multiple electronic components 70 is preferably 1500 μm or less, more preferably 1000 μm or less, even more preferably 500 μm or less, even more preferably 400 μm or less, even more preferably 300 μm or less, and even more preferably 200 μm or less, from the viewpoint of further suppressing the manufacturing efficiency of the electronic device 400, the occurrence of lifting between the support substrate 80 and the adhesive film 50, and the displacement of the electronic components 70 during the sealing process. Furthermore, the lower limit of the average spacing between the multiple electronic components 70 is not particularly limited, but may be 0 μm or more, 10 μm or more, 20 μm or more, 30 μm or more, 40 μm or more, 50 μm or more, 60 μm or more, 70 μm or more, 80 μm or more, 90 μm or more, or 100 μm or more.

[0028] When the electronic component 70 is rectangular, the coverage rate when attaching the electronic component 70 to the adhesive film 50, as calculated by the following formula (1), may be, for example, 80% or more, 85% or more, 88% or more, 90% or more, or 92% or more. Furthermore, the upper limit of the coverage rate calculated by the following formula (1) may be, for example, 100% or less, 99% or less, 98% or less, 97% or less, 96% or less, or 95% or less. Coverage rate (%) = 100 × [(vertical length of one electronic component) × (horizontal length of one electronic component) × (number of electronic components)] / {[(vertical length of one electronic component) + (average spacing between electronic components)] × [(horizontal length of one electronic component) + (average spacing between electronic components)] × (number of electronic components)} ...Formula (1)

[0029] [Step of sealing the electronic component 70 with sealing material 60] Next, the electronic component 70 is sealed with sealing material 60. The electronic component 70 is covered with sealing material 60, and the sealing material 60 is cured at a temperature of, for example, 150°C or lower to seal the electronic component 70. The form of the sealing material 60 is not particularly limited, but for example, it may be granular, sheet-like, or liquid.

[0030] The encapsulant 60 preferably includes one or more types selected from the group consisting of epoxy resin encapsulants and silicone resin encapsulants, and more preferably includes an epoxy resin encapsulant, as this improves the affinity of the encapsulant 60 to the adhesive film 50 and enables more uniform encapsulation of the electronic components 70. Examples of such epoxy resin encapsulants include the T693 / R4000 series, T693 / R1000 series, and T693 / R5000 series from Nagase ChemteX Corporation, and the G730 series from Sumitomo Bakelite Corporation. Examples of such silicone resin encapsulants include KMC-8400 from Shin-Etsu Chemical Co., Ltd., and TSE3033 and TSE3251 from Momentive Performance Materials Japan.

[0031] Examples of sealing methods include transfer molding, injection molding, compression molding, and casting. After sealing the electronic component 70 with the sealing material 60, the sealing material 60 is cured by heating at a temperature of, for example, 150°C or lower, to obtain a structure 100 in which the electronic component 70 is sealed.

[0032] The heating temperature for curing the sealant 60 is not particularly limited as long as it is a heating temperature that cures the sealant 60, but for example, it may be 100°C or more and 250°C or less. Also, the heating time for curing the sealant 60 is not particularly limited as long as it is a heating time that cures the sealant 60, but for example, it may be 10 seconds or more and 120 minutes or less.

[0033] [Other steps] The method for manufacturing the electronic device of this embodiment further includes a step of reducing the adhesive force of at least one of the adhesive resin layers (B) and adhesive resin layers (C) by external stimulation. This step allows the support substrate 80 or the electronic device 200 including the electronic component 70 to be easily peeled off from the structure 100. The external stimulation preferably includes one or more selected from the group consisting of light irradiation and heat treatment, and more preferably includes heat treatment from the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic component 70 during the sealing step. From the viewpoint of work efficiency, the heating time during the heat treatment is preferably 0.1 hours or more and 48 hours or less, more preferably 0.3 hours or more and 24 hours or less, even more preferably 0.5 hours or more and 12 hours or less, and more preferably 0.8 hours or more and 6 hours or less. Furthermore, the heating temperature during the heat treatment is not particularly limited as long as it is a temperature at which the adhesive strength of the layer whose adhesive strength is reduced by external stimuli decreases. However, from the viewpoint of work efficiency, it is preferably 100°C to 150°C, more preferably 110°C to 140°C, and even more preferably 120°C to 130°C.

[0034] The method for manufacturing the electronic device of this embodiment may further include a step of peeling the adhesive film 50 from the electronic component 70 to obtain the electronic device 200. Examples of methods for peeling the adhesive film 50 from the electronic component 70 include mechanical peeling and peeling after reducing the adhesive strength of the surface of the adhesive film 50.

[0035] The method for manufacturing the electronic device of this embodiment may further include the step of forming a wiring layer 310 and a bump 320 on the exposed surface of the obtained electronic device 200 to obtain the electronic device 300.

[0036] The wiring layer 310 comprises a pad (not shown), which is an external connection terminal formed on the outermost surface, and wiring (not shown) that electrically connects the exposed electronic component 70 to the pad. The wiring layer 310 can be formed by conventionally known methods and may have a multilayer structure.

[0037] Then, bumps 320 are formed on the pads of the wiring layer 310, and the electronic device 300 can be obtained. Examples of the bumps 320 include solder bumps and gold bumps. The solder bumps can be formed, for example, by placing solder balls on the pads which are the external connection terminals of the wiring layer 310 and heating to melt the solder (reflow). The gold bumps can be formed by methods such as the ball bonding method, the plating method, and the Au ball transfer method.

[0038] The manufacturing method of the electronic device of the present embodiment may further include a step of dicing the electronic device 300 to obtain a plurality of electronic devices 400. The dicing of the electronic device 300 can be performed by a known method.

[0039] The manufacturing method of the electronic device of the present embodiment can preferably be used for manufacturing an electronic device including a fan-out type package. That is, the electronic device obtained by the manufacturing method of the electronic device of the present embodiment includes a fan-out type package. In the fan-out type package, the terminals can be spread to the outside of the chip (fan out), so it can be adopted for applications with a large number of terminals compared to the chip area. Also, since the package substrate becomes unnecessary, thinning is also possible.

[0040] <Adhesive film 50> Hereinafter, the adhesive film 50 of the present embodiment will be described. FIGS. 1 to 2 are cross-sectional views schematically showing an example of the structure of the adhesive film 50 of the present embodiment.

[0041] As shown in FIG. 1, the adhesive film 50 of the present embodiment includes an adhesive resin layer (B), a base material layer (A), and an adhesive resin layer (C) in this order, and at least one selected from the adhesive resin layer (B) and the adhesive resin layer (C) includes a layer whose adhesive force decreases due to external stimuli.

[0042] The thickness of the entire adhesive film 50 is preferably 大于等于10μm and less than等于1000μm, more preferably 大于等于20μm and less than等于500μm, from the viewpoints of suppressing the generation of floating between the support substrate 80 and the adhesive film 50 and improving the performance balance of mechanical properties and handleability.

[0043] Next, each layer constituting the adhesive film 50 of this embodiment will be described.

[0044] [Base layer (A)] Base layer (A) is a layer provided for the purpose of improving the handling properties, mechanical properties, heat resistance, and other properties of the adhesive film 50. Base layer (A) preferably contains a thermoplastic resin. The thermoplastic resin preferably includes one or more selected from the group consisting of polyethylene, polypropylene, poly(4-methyl-1-pentene), poly(1-butene), etc.; polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, etc.; polyamides such as nylon-6, nylon-66, polymetaxylene adipamide, etc.; polyacrylate; polymethacrylate; polyvinyl chloride; polyvinylidene chloride; polyimide; polyetherimide; ethylene vinyl acetate copolymer; polyacrylonitrile; polycarbonate; polystyrene; ionomer; polysulfone; polyethersulfone; and polyphenylene ether, etc. More preferably, it includes one or more selected from the group consisting of polypropylene, polyethylene terephthalate, polyethylene naphthalate, polyamide, and polyimide, and even more preferably, it includes one or more selected from the group consisting of polyethylene terephthalate and polyethylene naphthalate.

[0045] The base layer (A) may be a single layer or two or more layers. The base layer (A) may be a stretched film or a film stretched in one or two axes, but from the viewpoint of improving the mechanical strength of the base layer (A), it preferably includes a film stretched in one or two axes.

[0046] From the viewpoint of obtaining good film properties, the thickness of the substrate layer (A) is preferably 1 μm to 500 μm, more preferably 5 μm to 300 μm, and even more preferably 10 μm to 250 μm. The substrate layer (A) may be surface-treated to improve its adhesion to other layers. Specifically, corona treatment, plasma treatment, undercoat treatment, primer coat treatment, etc., may be performed.

[0047] [Adhesive resin layer (B)] The adhesive film 50 of this embodiment is provided with an adhesive resin layer (B) on one side of the base layer (A). The adhesive resin layer (B) is a layer that contacts the surface of the electronic component 70 and temporarily fixes the electronic component 70 when the electronic component 70 is sealed with the sealing material 60 in the manufacturing process of an electronic device.

[0048] As described above, the adhesive film 50 of this embodiment includes at least one of the adhesive resin layers (B) and adhesive resin layers (C) selected from the group, in which the adhesive strength decreases due to external stimuli. The adhesive film 50 of this embodiment includes at least one of the adhesive resin layers (B) and adhesive resin layers (C) selected from the group, preferably one or more selected from the group consisting of a heat-peelable adhesive resin layer and a light-peelable adhesive resin layer, and more preferably a heat-peelable adhesive resin layer. The heat-peelable adhesive resin layer preferably includes one or more selected from the group consisting of a heat-expandable adhesive containing a gas-generating component, a heat-expandable adhesive containing thermally expandable microspheres that expand with heat to reduce adhesive strength, and a heat-expandable adhesive in which the adhesive strength decreases due to a crosslinking reaction of adhesive components with heat, and more preferably a heat-expandable adhesive containing a gas-generating component or thermally expandable microspheres.

[0049] The heat-peelable adhesive resin layer includes an adhesive resin layer whose adhesive strength decreases or is lost when heated at a temperature preferably above 100°C, more preferably above 110°C, even more preferably above 120°C, even more preferably above 130°C, even more preferably above 140°C, and even more preferably above 150°C. The heat-peelable adhesive resin layer preferably includes a material that does not peel at temperatures below 100°C, but whose adhesive strength decreases or is lost at temperatures above 100°C, and has an adhesive strength sufficient to prevent the adhesive film 50 from peeling off the support substrate 80 during the manufacturing process of the electronic device. Here, the decrease or loss of adhesive strength when heated at a temperature above 100°C can be evaluated, for example, by measuring the peel strength from the stainless steel plate after attaching the adhesive resin layer (C) side to a stainless steel plate, performing a heat treatment at 90°C for 1 hour, and then heating at a temperature above 100°C for 2 minutes. The specific heating temperature when heating to a temperature exceeding 100°C is set to a temperature higher than the temperature at which gas is generated or the temperature at which the thermally expandable microspheres expand, and is set appropriately depending on the type of gas generated or the thermally expandable microspheres. In this embodiment, loss of adhesive strength refers to, for example, when the 180° peel strength measured under conditions of 23°C and a tensile speed of 300 mm / min falls below 0.5 N / 25 mm.

[0050] The gas-generating components used in heat-expandable adhesives are preferably azo compounds; azide compounds; meldrum acid derivatives; inorganic blowing agents such as ammonium carbonate, ammonium bicarbonate, sodium bicarbonate, ammonium nitrite, sodium boro hydroxide, and various azides; water; salt fluoride alkane compounds such as trichloromonofluoromethane and dichloromonofluoromethane; azo compounds such as azobisisobutyronitrile, azodicarbonamide, and barium azodicarboxylate; and p-toluenesulfonyl hydrazide and diphenylsulfone-3,3'-disulfonyl hydrazide. The gas generating component may be added to the heat-expandable adhesive, or it may be directly bonded to the adhesive resin in the heat-expandable adhesive.

[0051] The heat-expandable microspheres used in heat-expandable adhesives preferably contain a microencapsulated foaming agent. Such heat-expandable microspheres preferably contain microspheres in which a substance that readily gasifies and expands upon heating, such as isobutane, propane, or pentane, is encapsulated within an elastic shell. The material constituting the shell preferably includes one or more selected from the group consisting of vinylidene chloride-acrylonitrile copolymer, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, polyacrylonitrile, polyvinylidene chloride, and polysulfone. The heat-expandable microspheres can be manufactured, for example, by coacervation or interfacial polymerization. The heat-expandable microspheres can be added to heat-expandable adhesives.

[0052] The content of at least one selected from the gas-generating component and the thermally expandable microspheres can be appropriately set according to the expansion ratio and adhesion reduction of the heat-peelable adhesive resin layer, but preferably it is 1 to 150 parts by mass, more preferably 10 to 130 parts by mass, and even more preferably 12 to 100 parts by mass, per 100 parts by mass of the adhesive resin in the heat-peelable adhesive resin layer. It is preferable to design the temperature at which the gas is generated and the temperature at which the thermally expandable microspheres expand are above 100°C.

[0053] Furthermore, if the adhesive resin layer (B) includes a layer whose adhesive strength decreases due to external stimuli, from the viewpoint of stably holding the adhesive film 50 on the support substrate 80 when peeling the electronic component 70 from the adhesive resin layer (B) by reducing the adhesive strength of the adhesive resin layer (B) by applying external stimuli, the content of at least one selected from gas-generating components and thermally expandable microspheres in the adhesive resin layer (C) is preferably 0.1% by mass or less, more preferably 0.05% by mass or less, and even more preferably 0.01% by mass or less, when the total amount of the adhesive resin layer (C) is 100% by mass, and even more preferably the adhesive resin layer (C) does not contain at least one selected from gas-generating components and thermally expandable microspheres.

[0054] The adhesive resin layer (B) preferably contains an adhesive resin (B1) from the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50. The adhesive resin (B1) preferably contains one or more selected from the group consisting of (meth)acrylic adhesive resin (b), silicone adhesive resin, urethane adhesive resin, olefin adhesive resin, and styrene adhesive resin, and more preferably contains (meth)acrylic adhesive resin (b) from the viewpoint of facilitating adjustment of adhesive strength. If the adhesive resin layer (B) includes a layer in which the adhesive strength decreases due to external stimuli, the adhesive resin (B1) is preferably included in a heat-expandable adhesive.

[0055] The (meth)acrylic adhesive resin (b) used in the adhesive resin layer (B) preferably contains as constituent units an alkyl (meth)acrylate monomer (b1) and a monomer (b2) having a functional group that can react with a crosslinking agent. In this embodiment, alkyl (meth)acrylate means alkyl acrylate, alkyl methacrylate, or a mixture thereof.

[0056] The (meth)acrylic adhesive resin (b) of this embodiment can preferably be obtained by copolymerizing a monomer mixture containing an alkyl (meth)acrylate monomer (b1) and a monomer (b2) having a functional group that can react with a crosslinking agent.

[0057] The alkyl (meth)acrylate monomer (b1) preferably includes an alkyl (meth)acrylate having an alkyl group having about 1 to 12 carbon atoms, and more preferably includes an alkyl (meth)acrylate having an alkyl group having 1 to 8 carbon atoms. The alkyl (meth)acrylate monomer (b1) preferably includes one or more selected from the group consisting of methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, and 2-ethylhexyl methacrylate. In the (meth)acrylic adhesive resin (b) according to this embodiment, the content of the alkyl (meth)acrylate monomer (b1) is preferably 10% by mass or more and 98.9% by mass or less, more preferably 50% by mass or more and 97% by mass or less, and even more preferably 85% by mass or more and 95% by mass or less, when the total amount of all monomer units in the (meth)acrylic adhesive resin (b) is taken as 100% by mass.

[0058] The monomer (b2) having a functional group that can react with the crosslinking agent preferably comprises one or more selected from the group consisting of acrylic acid, methacrylic acid, itaconic acid, mesaconic acid, citraconic acid, fumaric acid, maleic acid, monoalkyl itaconic acid, monoalkyl mesaconic acid, monoalkyl citraconic acid, monoalkyl fumaric acid, monoalkyl maleic acid, glycidyl acrylate, glycidyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, acrylamide, methacrylamide, tert-butylaminoethyl acrylate, and tert-butylaminoethyl methacrylate, and more preferably comprises one or more selected from the group consisting of acrylic acid, methacrylic acid, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, acrylamide, and methacrylamide. The content of monomers (b2) having functional groups that can react with a crosslinking agent in the (meth)acrylic adhesive resin (b) of this embodiment is preferably 1% by mass or more and 40% by mass or less, more preferably 1% by mass or more and 20% by mass or less, and even more preferably 1% by mass or more and 10% by mass or less, when the total amount of all monomer units in the (meth)acrylic adhesive resin (b) is taken as 100% by mass.

[0059] The (meth)acrylic adhesive resin (b) of this embodiment may further contain, in addition to monomers (b1) and (b2), a bifunctional monomer (b3) and a specific comonomer having surfactant properties (hereinafter referred to as a polymerizable surfactant) as constituent units. The polymerizable surfactant has the property of copolymerizing with monomers (b1), (b2), and (b3), and also acts as an emulsifier when emulsion polymerization occurs.

[0060] The bifunctional monomer (b3) is preferably 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, or a main chain structure with diacrylate or dimethacrylate at both ends and propylene It includes one or more types selected from the group consisting of glycol-type products (e.g., manufactured by Nippon Oil & Fats Co., Ltd., trade names: PDP-200, PDP-400, ADP-200, ADP-400), tetramethylene glycol-type products (e.g., manufactured by Nippon Oil & Fats Co., Ltd., trade names: ADT-250, ADT-850), and mixed types thereof (e.g., manufactured by Nippon Oil & Fats Co., Ltd., trade names: ADET-1800, ADPT-4000).

[0061] In the (meth)acrylic adhesive resin (b) of this embodiment, the content of the bifunctional monomer (b3) is preferably 0.1% by mass or more and 30% by mass or less, more preferably 0.1% by mass or more and 20% by mass or less, even more preferably 0.1% by mass or more and 15% by mass or less, and even more preferably 0.1% by mass or more and 5% by mass or less, when the total amount of all monomer units in the (meth)acrylic adhesive resin (b) is taken as 100% by mass.

[0062] The polymerizable surfactant preferably includes one or more selected from the group consisting of a polyoxyethylene nonylphenyl ether with a polymerizable 1-propenyl group introduced to the benzene ring (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.; trade names: Aqualon RN-10, RN-20, RN-30, RN-50, etc.), a polyoxyethylene nonylphenyl ether sulfate ammonium salt with a polymerizable 1-propenyl group introduced to the benzene ring (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.; trade names: Aqualon HS-10, HS-20, HS-1025, etc.), and sulfosuccinate diester surfactants 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) of this embodiment, the content of polymerizable surfactant is preferably 0.1% to 30% by mass, more preferably 0.1% to 20% by mass, even more preferably 0.1% to 15% by mass, and even more preferably 0.1% to 5% by mass, when the total amount of all monomer units in the (meth)acrylic adhesive resin (b) is taken as 100% by mass.

[0063] The (meth)acrylic adhesive resin (b) of this embodiment may further contain monomer units formed from monomers having polymerizable double bonds, such as vinyl acetate, acrylonitrile, and styrene, if necessary.

[0064] The polymerization reaction mechanism for the (meth)acrylic adhesive resin (b) of this embodiment can be radical polymerization, anionic polymerization, cationic polymerization, etc. Considering the manufacturing cost of the (meth)acrylic adhesive resin (b), the influence of the functional groups of the monomer, and the influence of ions on the surface of the electronic component 70, the polymerization reaction mechanism for the (meth)acrylic adhesive resin (b) of this embodiment is preferably radical polymerization. The radical polymerization initiator used when polymerization is carried out by radical polymerization is preferably 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-2-ethyl It comprises one or more selected from the group consisting of organic peroxides such as xanoates, 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.

[0065] When polymerization is carried out by emulsion polymerization, among these radical polymerization initiators, water-soluble inorganic peroxides such as ammonium persulfate, potassium persulfate, and sodium persulfate, and water-soluble azo compounds having a carboxyl group in the molecule, such as 4,4'-azobis-4-cyanovaleric acid, are preferred. Considering the influence of ions on the surface of the electronic component 70, azo compounds having a carboxyl group in the molecule, such as ammonium persulfate and 4,4'-azobis-4-cyanovaleric acid, are even more preferred, and azo compounds having a carboxyl group in the molecule, such as 4,4'-azobis-4-cyanovaleric acid, are particularly preferred.

[0066] In this embodiment, the adhesive resin layer (B) preferably further contains, in addition to the adhesive resin (B1), a crosslinking agent (B2) having two or more crosslinkable functional groups per molecule, from the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 during the sealing process. The crosslinking agent (B2) having two or more crosslinkable functional groups per molecule is used to react with the functional groups of the adhesive resin (B1) to adjust the adhesive strength and cohesive strength. The crosslinking agent (B2) is preferably an epoxy compound such as sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, glycerol polyglycidyl ether, neopentyl glycol diglycidyl ether, resolcin diglycidyl ether; an isocyanate compound such as tetramethylene diisocyanate, hexamethylene diisocyanate, trimethylolpropane toluene diisocyanate 3 adduct, polyisocyanate, diphenylmethane diisocyanate, tolylene diisocyanate; trimethylolpropane-tri-β-aziridinylpropionate, tetramethylolmethane-tri-β-aziridinylpropionate, N,N'-diphenyl The material comprises one or more compounds selected from the group consisting of aziridine compounds such as nylmethane-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 compounds such as N,N,N',N'-tetraglycidyl-m-xylenediamine and 1,3-bis(N,N'-diglycidylaminomethyl)cyclohexane; and melamine compounds such as hexamethoxymethylolmelamine, more preferably comprising one or more compounds selected from the group consisting of epoxy compounds, isocyanate compounds, and aziridine compounds.

[0067] Preferably, the amount of crosslinking agent (B2) is such that the number of functional groups in the crosslinking agent (B2) does not exceed the number of functional groups in the adhesive resin (B1). However, it may be included in excess as needed, such as when new functional groups are generated in the crosslinking reaction or when the crosslinking reaction is slow. From the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 in the sealing process, and from the viewpoint of improving the balance of heat resistance and adhesion performance of the adhesive resin layer (B), the amount of crosslinking agent (B2) in the adhesive resin layer (B) is preferably 0.1 parts by mass or more and 15 parts by mass or less, more preferably 0.5 parts by mass or more and 14 parts by mass or less, even more preferably 1.0 parts by mass or more and 13 parts by mass or less, even more preferably 1.5 parts by mass or more and 12 parts by mass or less, even more preferably 2.0 parts by mass or more and 11 parts by mass or less, and even more preferably 2.5 parts by mass or more and 10 parts by mass or less, per 100 parts by mass of adhesive resin (B1).

[0068] From the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 during the sealing process, the total content of the adhesive resin layer (B) is preferably 50% by mass or more and 100% by mass or less, more preferably 70% by mass or more and 100% by mass or less, even more preferably 90% by mass or more and 100% by mass or less, and even more preferably 95% by mass or more and 100% by mass or less, when the total content of the adhesive resin layer (B) is considered as 100% by mass.

[0069] When the adhesive resin layer (B) contains at least one selected from a gas-generating component and thermally expandable microspheres, the total content of the adhesive resin (B1), crosslinking agent (B2), and at least one selected from the gas-generating component and thermally expandable microspheres in the adhesive resin layer (B) is preferably 50% by mass or more and 100% by mass or less, more preferably 70% by mass or more and 100% by mass or less, even more preferably 90% by mass or more and 100% by mass or less, and even more preferably 95% by mass or more and 100% by mass or less, when the total content of the adhesive resin layer (B) is 100% by mass.

[0070] The thickness of the adhesive resin layer (B) is preferably 1 μm to 500 μm, more preferably 3 μm to 300 μm, even more preferably 5 μm to 100 μm, and even more preferably 10 μm to 50 μm, from the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 during the sealing process.

[0071] The adhesive resin layer (B) can be formed, for example, by applying an adhesive coating liquid onto a substrate layer (A), or by transferring an adhesive resin layer (B) formed on a separator onto the substrate layer (A). Conventional coating methods such as the roll coater method, reverse roll coater method, gravure roll method, bar coat method, comma coater method, and die coater method can be used for applying the adhesive coating liquid. There are no particular restrictions on the drying conditions of the applied adhesive coating liquid, but the drying temperature is preferably 60°C to 200°C, more preferably 65°C to 170°C, and even more preferably 65°C to 150°C, and the drying time is preferably 10 seconds to 10 minutes, more preferably 15 seconds to 5 minutes. In order to sufficiently promote the crosslinking reaction between the adhesive resin (B1) and the crosslinking agent (B2), the adhesive coating liquid may be heated for approximately 5 to 300 hours in a temperature range of 40°C to 80°C after drying is complete. Furthermore, the base material layer (A) and the adhesive resin layer (B) may be formed by co-extrusion molding, or the film-like base material layer (A) and the film-like adhesive resin layer (B) may be formed by lamination (stacking). Also, if the adhesive film 50 of this embodiment includes an intermediate layer (D) described later, the adhesive resin layer (B) may be formed, for example, by applying an adhesive coating liquid onto the intermediate layer (D), or by transferring an adhesive resin layer (B) formed on a separator onto the intermediate layer (D), or the base material layer (A) and intermediate layer (D) and the adhesive resin layer (B) may be formed by co-extrusion molding, or the film-like base material layer (A) and intermediate layer (D) and the film-like adhesive resin layer (B) may be formed by lamination (stacking).

[0072] [Adhesive resin layer (C)] The adhesive film 50 of this embodiment is provided with an adhesive resin layer (C) on the surface of the base layer (A) that is opposite to the surface on which the adhesive resin layer (B) is provided. The adhesive resin layer (C) is a layer that contacts the surface of the support substrate 80 and fixes the adhesive film 50 onto the support substrate 80 when sealing the electronic component 70 with the sealing material 60 in the manufacturing process of an electronic device.

[0073] As described above, the adhesive film 50 of this embodiment includes at least one of the adhesive resin layers (B) and adhesive resin layers (C) selected from each other, in which the adhesive strength decreases due to external stimuli. The adhesive film 50 of this embodiment includes at least one of the adhesive resin layers (B) and adhesive resin layers (C) selected from each other, preferably one or more selected from the group consisting of heat-peelable adhesive resin layers and light-peelable adhesive resin layers, and more preferably a heat-peelable adhesive resin layer. The heat-peelable adhesive resin layer can be the one described in [Adhesive resin layer (B)] above.

[0074] Furthermore, if the adhesive resin layer (C) includes a layer whose adhesive strength decreases due to external stimuli, from the viewpoint of stably holding the electronic component 70 on the adhesive resin layer (B) when the adhesive strength of the adhesive resin layer (C) is reduced by applying external stimuli and the support substrate 80 is peeled off from the adhesive resin layer (C), the content of at least one selected from gas-generating components and thermally expandable microspheres in the adhesive resin layer (B) is preferably 0.1% by mass or less, more preferably 0.05% by mass or less, and even more preferably 0.01% by mass or less, when the total amount of the adhesive resin layer (B) is 100% by mass, and even more preferably the adhesive resin layer (B) does not contain at least one selected from gas-generating components and thermally expandable microspheres.

[0075] The adhesive resin (C1) constituting the adhesive resin layer (C) preferably comprises one or more selected from the group consisting of (meth)acrylic adhesive resin (c), urethane adhesive resin, silicone adhesive resin, polyolefin adhesive resin, polyester adhesive resin, polyamide adhesive resin, fluorine adhesive resin, and styrene-diene block copolymer adhesive resin, and more preferably comprises (meth)acrylic adhesive resin (c). If the adhesive resin layer (C) includes a layer in which the adhesive strength decreases due to external stimuli, the adhesive resin (C1) is preferably included in a heat-expandable adhesive.

[0076] The (meth)acrylic adhesive resin (c) used in the adhesive resin layer (C) preferably comprises an alkyl (meth)acrylate monomer (c1) and a monomer (c2) having a functional group that can react with a crosslinking agent as constituent units.

[0077] The (meth)acrylic adhesive resin (c) of this embodiment can preferably be obtained by copolymerizing a monomer mixture containing an alkyl (meth)acrylate monomer (c1) and a monomer (c2) having a functional group that can react with a crosslinking agent.

[0078] The alkyl (meth)acrylate monomer (c1) preferably includes an alkyl (meth)acrylate having an alkyl group having about 1 to 12 carbon atoms, and more preferably includes an alkyl (meth)acrylate having an alkyl group having 1 to 8 carbon atoms. The alkyl (meth)acrylate monomer (c1) preferably includes one or more selected from the group consisting of methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, and 2-ethylhexyl methacrylate. In the (meth)acrylic adhesive resin (c) according to this embodiment, the content of alkyl (meth)acrylate monomer (c1) is preferably 10% by mass or more and 98.9% by mass or less, more preferably 50% by mass or more and 97% by mass or less, and even more preferably 85% by mass or more and 95% by mass or less, when the total amount of all monomer units in the (meth)acrylic adhesive resin (c) is taken as 100% by mass.

[0079] The monomer (c2) having a functional group that can react with the crosslinking agent preferably comprises one or more selected from the group consisting of acrylic acid, methacrylic acid, itaconic acid, mesaconic acid, citraconic acid, fumaric acid, maleic acid, monoalkyl itaconic acid, monoalkyl mesaconic acid, monoalkyl citraconic acid, monoalkyl fumaric acid, monoalkyl maleic acid, glycidyl acrylate, glycidyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, acrylamide, methacrylamide, tert-butylaminoethyl acrylate, and tert-butylaminoethyl methacrylate, and more preferably comprises one or more selected from the group consisting of acrylic acid, methacrylic acid, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, acrylamide, and methacrylamide. The content of monomers (c2) having functional groups that can react with a crosslinking agent in the (meth)acrylic adhesive resin (c) of this embodiment is preferably 1% by mass or more and 40% by mass or less, more preferably 1% by mass or more and 20% by mass or less, and even more preferably 1% by mass or more and 10% by mass or less, when the total amount of all monomer units in the (meth)acrylic adhesive resin (c) is taken as 100% by mass.

[0080] The (meth)acrylic adhesive resin (c) of this embodiment may further contain, in addition to monomers (c1) and monomer (c2), a bifunctional monomer (c3) and a specific comonomer having surfactant properties (hereinafter referred to as a polymerizable surfactant) as constituent units. The polymerizable surfactant has the property of copolymerizing with monomers (c1), monomer (c2), and monomer (c3), and also acts as an emulsifier when emulsion polymerization occurs.

[0081] The bifunctional monomer (c3) is preferably 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, or a main chain structure of propylene with diacrylate or dimethacrylate at both ends. It includes one or more types selected from the group consisting of glycol-type products (e.g., manufactured by Nippon Oil & Fats Co., Ltd., trade names: PDP-200, PDP-400, ADP-200, ADP-400), tetramethylene glycol-type products (e.g., manufactured by Nippon Oil & Fats Co., Ltd., trade names: ADT-250, ADT-850), and mixed types thereof (e.g., manufactured by Nippon Oil & Fats Co., Ltd., trade names: ADET-1800, ADPT-4000).

[0082] In the (meth)acrylic adhesive resin (c) of this embodiment, the content of the bifunctional monomer (c3) is preferably 0.1% by mass or more and 30% by mass or less, more preferably 0.1% by mass or more and 20% by mass or less, even more preferably 0.1% by mass or more and 15% by mass or less, and even more preferably 0.1% by mass or more and 5% by mass or less, when the total amount of all monomer units in the (meth)acrylic adhesive resin (c) is taken as 100% by mass.

[0083] The polymerizable surfactant preferably includes one or more selected from the group consisting of a polyoxyethylene nonylphenyl ether with a polymerizable 1-propenyl group introduced to the benzene ring (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.; trade names: Aqualon RN-10, RN-20, RN-30, RN-50, etc.), a polyoxyethylene nonylphenyl ether sulfate ammonium salt with a polymerizable 1-propenyl group introduced to the benzene ring (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.; trade names: Aqualon HS-10, HS-20, HS-1025, etc.), and sulfosuccinate diester surfactants 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 (c) of this embodiment, the content of polymerizable surfactant is preferably 0.1% to 30% by mass, more preferably 0.1% to 20% by mass, even more preferably 0.1% to 15% by mass, and even more preferably 0.1% to 5% by mass, when the total amount of all monomer units in the (meth)acrylic adhesive resin (c) is taken as 100% by mass.

[0084] The (meth)acrylic adhesive resin (c) of this embodiment may further contain monomer units formed from monomers having polymerizable double bonds, such as vinyl acetate, acrylonitrile, and styrene, if necessary.

[0085] The polymerization reaction mechanism for the (meth)acrylic adhesive resin (c) of this embodiment can be radical polymerization, anionic polymerization, cationic polymerization, etc. Considering the manufacturing cost of the (meth)acrylic adhesive resin (c), the influence of the functional groups of the monomer, and the influence of ions on the surface of the electronic component 70, the polymerization reaction mechanism for the (meth)acrylic adhesive resin (c) of this embodiment is preferably radical polymerization. The radical polymerization initiator used when polymerization is carried out by radical polymerization is preferably 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-2-ethyl It comprises one or more selected from the group consisting of organic peroxides such as xanoates, 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.

[0086] When polymerization is carried out by emulsion polymerization, among these radical polymerization initiators, water-soluble inorganic peroxides such as ammonium persulfate, potassium persulfate, and sodium persulfate, and water-soluble azo compounds having a carboxyl group in the molecule, such as 4,4'-azobis-4-cyanovaleric acid, are preferred. Considering the influence of ions on the surface of the electronic component 70, azo compounds having a carboxyl group in the molecule, such as ammonium persulfate and 4,4'-azobis-4-cyanovaleric acid, are even more preferred, and azo compounds having a carboxyl group in the molecule, such as 4,4'-azobis-4-cyanovaleric acid, are particularly preferred.

[0087] In this embodiment, the adhesive resin layer (C) preferably further includes, in addition to the adhesive resin (C1), a crosslinking agent (C2) having two or more crosslinkable functional groups per molecule, from the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 during the sealing process. The crosslinking agent (C2) having two or more crosslinkable functional groups per molecule is used to react with the functional groups of the adhesive resin (C1) to adjust the adhesive strength and cohesive strength. The crosslinking agent (C2) is preferably an epoxy compound such as sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, glycerol polyglycidyl ether, neopentyl glycol diglycidyl ether, or resolcin diglycidyl ether; an isocyanate compound such as tetramethylene diisocyanate, hexamethylene diisocyanate, trimethylolpropane toluene diisocyanate 3 adduct, polyisocyanate, diphenylmethane diisocyanate, or tolylene diisocyanate; or trimethylolpropane-tri-β-aziridinylpropionate, tetramethylolmethane-tri-β-aziridinylpropionate, or N,N'-diphenyl The material comprises one or more compounds selected from the group consisting of aziridine compounds such as nylmethane-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 compounds such as N,N,N',N'-tetraglycidyl-m-xylenediamine and 1,3-bis(N,N'-diglycidylaminomethyl)cyclohexane; and melamine compounds such as hexamethoxymethylolmelamine, more preferably comprising one or more compounds selected from the group consisting of epoxy compounds, isocyanate compounds, and aziridine compounds.

[0088] Preferably, the amount of crosslinking agent (C2) is such that the number of functional groups in the crosslinking agent (C2) does not exceed the number of functional groups in the adhesive resin (C1). However, it may be included in excess as needed, such as when new functional groups are generated in the crosslinking reaction or when the crosslinking reaction is slow. From the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 in the sealing process, and from the viewpoint of improving the balance between the heat resistance and adhesion performance of the adhesive resin layer (C), the amount of crosslinking agent (C2) in the adhesive resin layer (C) is preferably 0.1 parts by mass to 15 parts by mass, more preferably 0.5 parts by mass to 10 parts by mass, even more preferably 1.0 part by mass to 5 parts by mass, and even more preferably 1.5 parts by mass to 3 parts by mass per 100 parts by mass of adhesive resin (C1).

[0089] From the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 during the sealing process, the total content of the adhesive resin layer (C) is preferably 50% by mass or more and 100% by mass or less, more preferably 70% by mass or more and 100% by mass or less, even more preferably 90% by mass or more and 100% by mass or less, and even more preferably 95% by mass or more and 100% by mass or less, when the total content of the adhesive resin layer (C) is considered as 100% by mass.

[0090] When the adhesive resin layer (C) contains at least one selected from a gas-generating component and thermally expandable microspheres, the total content of the adhesive resin (C1), crosslinking agent (C2), and at least one selected from the gas-generating component and thermally expandable microspheres in the adhesive resin layer (C) is preferably 50% to 100% by mass, more preferably 70% to 100% by mass, even more preferably 90% to 100% by mass, and even more preferably 95% to 100% by mass, when the total content of the adhesive resin layer (C) is 100% by mass.

[0091] The adhesive resin layer (C) according to this embodiment preferably further contains a tackifying resin in addition to the adhesive resin (C1) from the viewpoint of improving adhesion to the support substrate 80. By including a tackifying resin in the adhesive resin layer (C), it becomes easier to adjust the adhesion to the support substrate 80 at or near room temperature. The tackifying resin preferably has a softening point of 100°C or higher. The tackifying resin includes one or more selected from the group consisting of rosin-based resins such as rosin derivatives that have been treated with 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; petroleum resins obtained by hydrogenating, disproportionating, polymerizing, or maleinating these natural rosins; and coumarone-indene resins.

[0092] The softening point of the tackifying resin is preferably 100°C or higher, more preferably 100°C to 160°C, and even more preferably 120°C to 150°C. Using a tackifying resin with a softening point within the above range not only reduces contamination and adhesive residue on the support substrate 80, but also further improves adhesion to the support substrate 80 in the working environment. Furthermore, using a tackifying resin containing a rosin-based resin not only reduces contamination and adhesive residue on the support substrate 80, but also improves the adhesion of the adhesive film 50 to the support substrate 80 in an environment of 80 to 130°C, and after the thermally expandable microspheres expand, the adhesive film 50 can be peeled off the support substrate 80 even more easily.

[0093] The content of the tackifying resin can be appropriately selected so as to adjust the elastic modulus of the adhesive resin layer (C) to a desired predetermined numerical range, and there are no particular restrictions. From the viewpoint of balancing the performance of the elastic modulus of the adhesive resin layer (C) and the initial peeling force, the content of the tackifying resin is preferably 1 to 100 parts by mass per 100 parts by mass of the adhesive resin (C1), and more preferably 2 to 50 parts by mass from the viewpoint of balancing the performance of adhesion to the support substrate 80 and adhesiveness at room temperature. When the content of the tackifying resin is above the lower limit per 100 parts by mass of the adhesive resin (C1), adhesion to the support substrate 80 during work tends to be good. On the other hand, when it is below the upper limit, adhesiveness to the support substrate 80 at room temperature tends to be good. Furthermore, the acid value of the tackifying resin is preferably 30 or less. When the acid value of the tackifying resin is below the upper limit, adhesive residue tends to be less likely to be left on the support substrate 80 when peeled off.

[0094] The thickness of the adhesive resin layer (C) is preferably 1 μm to 500 μm, more preferably 5 μm to 300 μm, even more preferably 10 μm to 150 μm, even more preferably 15 μm to 100 μm, and even more preferably 20 μm to 70 μm, from the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 during the sealing process.

[0095] The adhesive resin layer (C) can be formed, for example, by applying an adhesive coating liquid onto a substrate layer (A), or by transferring an adhesive resin layer (C) formed on a separator onto the substrate layer (A). Conventional known coating methods such as the roll coater method, reverse roll coater method, gravure roll method, bar coat method, comma coater method, and die coater method can be used for applying the adhesive coating liquid. There are no particular restrictions on the drying conditions of the applied adhesive coating liquid, but the drying temperature is preferably 60°C to 200°C, more preferably 65°C to 170°C, and even more preferably 65°C to 150°C, and the drying time is preferably 10 seconds to 10 minutes, more preferably 15 seconds to 5 minutes. In order to sufficiently promote the crosslinking reaction between the adhesive resin (C1) and the crosslinking agent (C2), the adhesive coating liquid may be heated for about 5 hours to 300 hours in a temperature range of 40°C to 80°C after drying is complete. Furthermore, the base material layer (A) and the adhesive resin layer (C) may be formed by co-extrusion molding, or by laminating (stacking) a film-like base material layer (A) and a film-like adhesive resin layer (C). Also, if the adhesive film 50 of this embodiment includes an intermediate layer (D) described later, the adhesive resin layer (C) may be formed, for example, by applying an adhesive coating liquid onto the intermediate layer (D), or by transferring an adhesive resin layer (C) formed on a separator onto the intermediate layer (D), or by co-extrusion molding of the base material layer (A) and intermediate layer (D) and the adhesive resin layer (C), or by laminating (stacking) a film-like base material layer (A) and intermediate layer (D) and the film-like adhesive resin layer (C).

[0096] [Intermediate layer (D)] As shown in Figure 2, the adhesive film 50 of this embodiment preferably further includes an intermediate layer (D) selected from at least one of the following: between the base layer (A) and the adhesive resin layer (B), and between the base layer (A) and the adhesive resin layer (C), in order to further suppress the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 during the sealing process. Figure 2 shows an embodiment in which the adhesive film 50 of this embodiment further includes an intermediate layer (D) between the base layer (A) and the adhesive resin layer (B).

[0097] The intermediate layer (D) preferably includes a layer that hardens upon external stimulation, from the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 during the sealing process.

[0098] The resin constituting the intermediate layer (D) preferably comprises one or more selected from the group consisting of (meth)acrylic resins, urethane resins, silicone resins, polyolefin resins, polyester resins, polyamide resins, fluororesins, and styrene-diene block copolymer resins, more preferably comprising one or more selected from the group consisting of (meth)acrylic resins and polyolefin resins, and even more preferably comprising a (meth)acrylic resin.

[0099] The intermediate layer (D) preferably contains a crosslinking agent, from the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 during the sealing process. Examples of crosslinking agents used in the intermediate layer (D) of this embodiment include those that undergo a crosslinking reaction with chemical species generated from the initiator. The crosslinking agent used in the intermediate layer (D) of this embodiment preferably contains one or more selected from the group consisting of polyfunctional (meth)acrylate compounds and isocyanate compounds, from the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 during the sealing process.

[0100] The amount of crosslinking agent in the intermediate layer (D) is preferably within a range such that the number of functional groups in the crosslinking agent does not exceed the number of functional groups in the adhesive resin. However, it may be included in excess as needed, such as when new functional groups are generated in the crosslinking reaction or when the crosslinking reaction is slow. The amount of crosslinking agent in the intermediate layer (D) is preferably 0.1 parts by mass or more and 10 parts by mass or less, more preferably 0.5 parts by mass or more and 5 parts by mass or less, per 100 parts by mass of resin in the intermediate layer (D).

[0101] The total content of resin and crosslinking agent in the intermediate layer (D) is preferably 50% by mass or more and 100% by mass or less, more preferably 70% by mass or more and 100% by mass or less, even more preferably 90% by mass or more and 100% by mass or less, and even more preferably 95% by mass or more and 100% by mass or less, when the entire intermediate layer (D) is considered to be 100% by mass.

[0102] The intermediate layer (D) preferably contains an initiator. The initiator preferably contains one or more selected from the group consisting of thermal initiators that generate activated species by heat and photoinitiators that generate activated species by light.

[0103] The thermal initiator is not particularly limited, as long as it is capable of crosslinking the resin and / or crosslinking agent in the intermediate layer (D) by thermal energy. The chemical species generated from the thermal initiator may be appropriately selected based on the functional groups of the resin and / or crosslinking agent. The chemical species generated from the thermal initiator are typically radicals or cations.

[0104] From the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 during the sealing process, the thermal initiator preferably comprises one or more selected from the group consisting of aromatic ketones, onium salt compounds, organic peroxides, thio compounds, hexaarylbiimidazole compounds, ketoxime ester compounds, borate compounds, azinium compounds, metallocene compounds, active ester compounds, compounds having carbon-halogen bonds, and azo compounds. From the viewpoint of availability and ease of handling, it more preferably comprises one or more selected from the group consisting of azo compounds or organic peroxides, and even more preferably comprises organic peroxides.

[0105] Commercially available thermal initiators include V-70, V-65, V-601, V-59, V-40, VF-096, V-30, VAm-110, VAm-111 (all manufactured by Fujifilm Wako Pure Chemical Industries), Niper BW, Niper BMT, Perloyl TCP, Perloyl L, Perloyl 355, Perloyl SA, Perhexa HC, Perbutyl 355, Perbutyl D, Perbutyl L, Perbutyl ND, Perocta O, Perhexyl D, Perhexyl O, Perhexyl PV (all manufactured by NOF Corporation), Trigonox 36-C75, Laurox, Percadox L-W75, Percadox CH-50L, Trigonox TMBH, Kayakumen H, Kayabutyl H-70, Percadox BC-FF, Kayahex Examples include SA AD, Percadox 14, Kayabutyl C, Kayabutyl D, Percadox 12-XL25, Trigonox 22-N70 (22-70E), Trigonox D-T50, Trigonox 423-C70, Kayaester CND-C70, Trigonox 23-C70, Trigonox 257-C70, Kayaester P-70, Kayaester TMPO-70, Trigonox 121, Kayaester O, Kayaester HTP-65W, Kayaester AN, Trigonox 42, Trigonox F-C50, Kayabutyl B, Kayacarbon EH, Kayacarbon I-20, Kayacarbon BIC-75, Trigonox 117, Kayaren 6-70 (all manufactured by Kayaku Akzo).

[0106] From the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 during the sealing process, the amount of thermal initiator is preferably 0.1 parts by mass to 7 parts by mass, more preferably 0.3 parts by mass to 7 parts by mass, and even more preferably 0.5 parts by mass to 3 parts by mass, per 100 parts by mass of resin in the intermediate layer (D).

[0107] The photoinitiator is not particularly limited, as long as it is capable of crosslinking the resin and / or crosslinking agent in the intermediate layer (D) by light energy. The chemical species generated from the photoinitiator may be appropriately selected based on the functional groups of the resin and / or crosslinking agent. The chemical species generated from the photoinitiator are typically radicals or cations.

[0108] From the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 during the sealing process, the photoinitiator preferably comprises one or more selected from the group consisting of alkylphenone-based photoinitiators, acetophenone-based photoinitiators, oxime ester-based photoinitiators, benzoin ether-based photoinitiators, acylphosphine oxide-based photoinitiators, α-ketol-based photoinitiators, aromatic sulfonyl chloride-based photoinitiators, photoactive oxime-based photoinitiators, benzoin-based photoinitiators, benzyl-based photoinitiators, benzophenone-based photoinitiators, and thioxanthone-based photoinitiators, and more preferably comprises alkylphenone-based photoinitiators from the viewpoint of high reactivity and low sublimation.

[0109] The alkylphenone-based photoinitiator preferably comprises one or more selected from the group consisting of 2-benzyl-2-(dimethylamino)-4'-morpholinobtyrophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxycyclohexylphenyl-ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-propan-1-one, and 2-hydroxy-1-{[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propan-1-one. The acetophenone-based photoinitiator preferably comprises one or more selected from the group consisting of 1-hydroxycyclohexyl-phenyl-ketone, 4-phenoxydichloroacetophenone, 4-t-butyl-dichloroacetophenone, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, and methoxyacetophenone. The oxime ester-based photoinitiator preferably comprises one or more selected from the group consisting of 1,2-octanedione, 1-[4-(phenylthio)phenyl]-2-(o-benzoyloxime)ethanone, and 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-1-(o-acetyloxime). The benzoin ether-based photoinitiator preferably comprises one or more selected from the group consisting of benzoin ethers such as benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, and benzoin isobutyl ether, and substituted benzoin ethers such as anisole methyl ether.Acylphosphine oxide photoinitiators preferably comprise one or more selected from the group consisting of bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-2,4-di-n-butoxyphenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide. Alpha-ketol photoinitiators preferably comprise one or more selected from the group consisting of 2-methyl-2-hydroxypropiophenone and 1-[4-(2-hydroxyethyl)phenyl]-2-methylpropan-1-one. Aromatic sulfonyl chloride photoinitiators preferably comprise 2-naphthalenesulfonyl chloride. Photoactive oxime photoinitiators preferably comprise 1-phenyl-1,1-propanedione-2-(o-ethoxycarbonyl)-oxime. Benzoin-based photoinitiators preferably contain benzoin. Benzyl-based photoinitiators preferably contain benzyl. Benzophenone-based photoinitiators preferably contain one or more selected from the group consisting of benzoylbenzoic acid, 3,3'-dimethyl-4-methoxybenzophenone, polyvinylbenzophenone, and α-hydroxycyclohexylphenyl ketone. Thioxanthone-based photoinitiators preferably contain one or more selected from the group consisting of thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, isopropylthioxanthone, 2,4-diisopropylthioxanthone, and dodecylthioxanthone.

[0110] Preferably, a photoinitiator that absorbs light with a wavelength of 300 nm or more (for example, light with a wavelength of 300 nm to 500 nm) and generates radicals can be used. The photoinitiator can be used alone or in appropriate combinations of two or more types.

[0111] From the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 during the sealing process, the amount of photoinitiator is preferably 0.1 parts by mass to 7 parts by mass, more preferably 0.3 parts by mass to 7 parts by mass, and even more preferably 0.5 parts by mass to 3 parts by mass, per 100 parts by mass of resin in the intermediate layer (D).

[0112] The intermediate layer (D) may be a single layer or a multilayer layer. The thickness of the intermediate layer (D) is preferably 5 μm to 1000 μm, more preferably 10 μm to 500 μm, and even more preferably 15 μm to 300 μm, from the viewpoint of further suppressing the occurrence of lifting between the support substrate 80 and the adhesive film 50 and the displacement of the electronic components 70 during the sealing process.

[0113] The intermediate layer (D) can be formed, for example, by applying an intermediate layer forming coating solution onto the base layer (A), or by transferring an intermediate layer (D) formed on a separator onto the base layer (A). Conventional coating methods such as the roll coater method, reverse roll coater method, gravure roll method, bar coat method, comma coater method, and die coater method can be used for applying the intermediate layer forming coating solution. There are no particular restrictions on the drying conditions of the applied intermediate layer forming coating solution, but the drying temperature is preferably 60°C to 200°C, more preferably 65°C to 170°C, and even more preferably 65°C to 150°C. The drying time is preferably 10 seconds to 10 minutes, more preferably 15 seconds to 5 minutes. In order to sufficiently promote the crosslinking reaction in the intermediate layer forming coating solution, after the drying of the intermediate layer forming coating solution is completed, it may be heated in a temperature range of 40°C to 80°C for about 5 hours to 300 hours. Furthermore, the base layer (A) and the intermediate layer (D) may be formed by co-extrusion molding, or they may be formed by laminating (layering) a film-like base layer (A) and a film-like intermediate layer (D).

[0114] [Other Layers] The adhesive film 50 according to this embodiment may further have layers such as an unevenness-absorbing layer, an impact-absorbing layer, or an easy-adhesion layer between the base layer (A) and the adhesive resin layer (B) or between the base layer (A) and the adhesive resin layer (C), to the extent that it does not impair the effects of this embodiment.

[0115] The embodiments of the present invention have been described above, but these are merely examples, and various other configurations can also be adopted.

[0116] It should be noted that the present invention is not limited to the embodiments described above, and any modifications, improvements, etc., that can achieve the objectives of the present invention are included in the present invention.

[0117] The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited thereto.

[0118] The details of the method for producing the adhesive film are as follows.

[0119] <Adhesive Resin Solution SB1> To deionized pure water, 0.5 parts by mass of 4,4'-azobis-4-cyanovaleric acid (manufactured by Otsuka Chemical Co., Ltd., trade name: ACVA) was added as a polymerization initiator, 74.3 parts by mass of n-butyl acrylate and 13.7 parts by mass of methyl methacrylate as monomer (b1), 9 parts by mass of 2-hydroxyethyl methacrylate as monomer (b2), and 3 parts by mass of a polymerizable surfactant, which is an ammonium salt of the sulfate ester of polyoxyethylene nonylphenyl ether with a polymerizable 1-propenyl group introduced to the benzene ring (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.; trade name: Aqualon HS-1025). Emulsification polymerization was carried out at 70-72°C for 8 hours under stirring to obtain an acrylic resin emulsion. This was neutralized with ammonia water (pH = 7.0) to obtain adhesive resin solution SB1 with a solid content concentration of 42.5%.

[0120] <Adhesive Resin Solution SB2> In deionized pure water, 0.5 parts by mass of ammonium persulfate was added as a polymerization initiator, 63 parts by mass of 2-ethylhexyl acrylate, 21 parts by mass of n-butyl acrylate, and 9 parts by mass of methyl methacrylate as monomers (b1), 3 parts by mass of 2-hydroxyethyl methacrylate as monomer (b2), 1 part by mass of polytetramethylene glycol diacrylate (manufactured by Nippon Oil & Fats Co., Ltd., trade name: ADT-250) as monomer (b3), and 2 parts by mass of a polymerizable surfactant, which is an ammonium salt of the sulfate ester of polyoxyethylene nonylphenyl ether with a polymerizable 1-propenyl group introduced to the benzene ring (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name: Aqualon HS-1025). Emulsification polymerization was carried out at 70-72°C for 8 hours under stirring to obtain an acrylic resin emulsion. This was neutralized with ammonia water (pH = 7.0) to obtain a sticky resin solution SB2 with a solid content concentration of 56.5%.

[0121] <Adhesive Coating Solution B1> Adhesive coating solution B1 was obtained by mixing 57.4 parts by mass of adhesive resin solution SB1, 42.6 parts by mass of adhesive resin solution SB2, 0.4 parts by mass of dimethylethanolamine, and 3.4 parts by mass of an epoxy compound (manufactured by Nagase ChemteX, Ex-1610), which is a crosslinking agent.

[0122] <Adhesive Resin Solution SC1> In a mixed solvent containing ethyl acetate and toluene, 0.536 parts by mass of t-butylperoxy-2-ethylhexanoate (manufactured by Nippon Oil & Fats Co., Ltd., trade name: Perbutyl O (registered trademark)) was added as a polymerization initiator, 34.9 parts by mass of 2-ethylhexyl acrylate, 41 parts by mass of n-butyl acrylate, and 14.7 parts by mass of ethyl acrylate were added as monomers (c1), and 9.4 parts by mass of 2-hydroxyethyl methacrylate was added as monomer (c2). Solution polymerization was carried out at 83-87°C for 11 hours under stirring to obtain an acrylic resin solution with a solid content of 45% by mass. This was designated as adhesive resin solution SC1.

[0123] <Adhesive Coating Solution C1> 100 parts by mass of adhesive resin solution SC1 and 0.9 parts by mass of an isocyanate compound (manufactured by Mitsui Chemicals, Inc., trade name: Olestar P49-75S) as a crosslinking agent (2 parts by mass per 100 parts by mass of adhesive resin) were mixed, and the solid content concentration was adjusted to 40% with ethyl acetate to obtain adhesive coating solution C1.

[0124] <Adhesive Coating Solution C2> Adhesive coating solution C2 was prepared by mixing 100 parts by mass of adhesive resin solution SC1, 2.25 parts by mass of polymerized rosin ester tackifier (manufactured by Arakawa Chemical Industries, Ltd., trade name: Pencel D-125) (5 parts by mass per 100 parts by mass of adhesive resin), 1.2 parts by mass of isocyanate compound (manufactured by Mitsui Chemicals, Inc., trade name: Olestar P49-75S) as a crosslinking agent (2.67 parts by mass per 100 parts by mass of adhesive resin), and 6.75 parts by mass of thermally expandable microspheres (manufactured by Sekisui Chemical Co., Ltd., trade name: Advancell EM-503) (15 parts by mass per 100 parts by mass of adhesive resin), and adjusting the solid content concentration to 30% with ethyl acetate.

[0125] [Example 1] Adhesive coating liquid B1 was applied to a polyethylene terephthalate (PET) film (38 μm thick), which was the base layer, and then dried at 120°C for 2 minutes to form an adhesive resin layer (B) with a thickness of 10 μm. Next, adhesive coating liquid C1 was applied to a separator with a thickness of 31 μm, separate from the base layer, and dried at 120°C for 2 minutes to obtain a resin film (D). The side of this resin film (D) that was not in contact with the separator was attached to the surface of the PET film opposite to the adhesive resin layer (B) to form an intermediate layer (D) with a thickness of 20 μm. Then, adhesive coating liquid C2 was applied to another separator with a thickness of 31 μm, and dried at 120°C for 2 minutes to obtain an adhesive resin film (C). After peeling off the separator on the intermediate layer (D), the non-contacting side of the adhesive resin film (C) was attached to the surface of the intermediate layer (D) from which the separator had been peeled off, forming a heat-peelable adhesive resin layer (C) with a thickness of 30 μm, thereby obtaining an adhesive film. Note that the adhesive resin layer (C) contains thermally expandable microspheres, and therefore its adhesive strength decreases when external stimuli such as heat treatment are applied. Next, after peeling off the separator on the adhesive resin layer (C) side of the obtained adhesive film, the adhesive resin layer (C) side was bonded to a 320 mm square SUS substrate. Subsequently, the adhesive film and the SUS substrate were heat-treated at a heating temperature of 130°C for 60 minutes to reduce the amount of volatile components in the adhesive film. Next, 1000 semiconductor chips, each measuring 5.0 mm in length and 5.0 mm in width, were placed on an adhesive resin layer (B) of an adhesive film, adhering tightly to each other so that the electronic components were spaced in a grid pattern with a spacing of 150 μm between them. The average spacing between semiconductor chips (average spacing between electronic components) was calculated based on the individual spacing of the 1000 semiconductor chips. Subsequently, the adhesive strength of the adhesive resin layer (B) and adhesive resin layer (C) was stabilized by heat treatment at a heating temperature of 130°C for a heating time of 30 minutes to obtain a structure. Ten minutes after obtaining the structure, the multiple semiconductor chips on the adhesive resin layer (B) were sealed by compression molding at 135°C using a granular epoxy resin-based encapsulant (Sumitomo Bakelite Co., Ltd., product name: G730) using a compression molding machine to obtain electronic device 1.Furthermore, even when the heating temperature used to reduce the amount of volatile components in the adhesive film by heat-treating the adhesive film and the SUS substrate was set to 100°C and 150°C, the same results as in Example 1 were obtained in both cases.

[0126] [Comparative Example 1] An electronic device 2 was obtained in the same manner as in Example 1, except that the adhesive film and the SUS substrate were not heat-treated under the conditions of heating temperature: 130°C and heating time: 60 minutes.

[0127] [Comparative Example 2] First, an adhesive film was obtained in the same manner as in Example 1. Next, the adhesive resin layer (C) side of the obtained adhesive film was bonded to a 320 mm square SUS substrate. Then, as electronic components, 1000 semiconductor chips measuring 5.0 mm vertically x 5.0 mm horizontally were placed on the adhesive resin layer (B) of the adhesive film in a grid pattern with 150 μm intervals and adhered tightly. The average spacing between semiconductor chips (average spacing between electronic components) was calculated based on the spacing of each of the 1000 semiconductor chips. Next, the adhesive strength of the adhesive resin layer (B) and adhesive resin layer (C) was stabilized by heat treatment at 130°C for 30 minutes to obtain a structure. Two days after obtaining the structure, the amount of volatile components in the structure was reduced by heat treatment at a heating temperature of 130°C for 60 minutes. Ten minutes after the structure was heat-treated, multiple semiconductor chips on the adhesive resin layer (B) were sealed by compression molding at 135°C using a compression molding machine with a granular epoxy resin-based encapsulant (manufactured by Sumitomo Bakelite Co., Ltd., product name: G730) to obtain the electronic device 3.

[0128] <Evaluation> (Coverage Rate) For each example and comparative example, the coverage rate was calculated using the following formula (1). The results are shown in Table 1. Coverage Rate (%) = 100 × [(Length of one electronic component) × (Width of one electronic component) × (Number of electronic components)] / {[(Length of one electronic component) + (Average spacing between electronic components)] × [(Width of one electronic component) + (Average spacing between electronic components)] × (Number of electronic components)} ...Formula (1)

[0129] (Lifting between the support substrate and the adhesive film) For electronic devices 1 to 3 obtained in the examples and each comparative example, the lifting between the support substrate and the adhesive film after sealing with the sealing material was checked visually and by pressing down on the sealing material with a finger, and evaluated according to the following criteria. The results are shown in Table 1. A: No lifting occurred between the support substrate and the adhesive film. B: Lifting occurred between the support substrate and the adhesive film.

[0130] (Misalignment of Electronic Components) For electronic devices 1 to 3 obtained in the examples and each comparative example, the number of electronic components that were misaligned after sealing with the sealing material was visually confirmed and evaluated according to the following criteria. The results are shown in Table 1. A: 0 electronic components were misaligned B: 1 to 20 electronic components were misaligned C: 21 or more electronic components were misaligned

[0131]

[0132] As shown in the example, it can be seen that the occurrence of lifting between the support substrate and the adhesive film can be suppressed by reducing the amount of volatile components in the adhesive film after bonding the support substrate and the adhesive film together.

[0133] This application claims priority based on Japanese Patent Application No. 2024-229906, filed on 26 December 2024, and incorporates all of its disclosures herein.

[0134] A Base layer (A) B Adhesive resin layer (B) C Adhesive resin layer (C) D Intermediate layer (D) 50 Adhesive film 60 Encapsulating material 70 Electronic component 80 Support substrate 100 Structure 200 Electronic device 300 Electronic device 310 Wiring layer 320 Bump 400 Electronic device

Claims

1. A method for manufacturing an electronic device, comprising the steps of: preparing an adhesive film containing an adhesive resin layer (B), a base layer (A), and an adhesive resin layer (C) in that order; then attaching a support substrate to the adhesive resin layer (C) side of the adhesive film; reducing the amount of volatile components in the adhesive film; attaching an electronic component to the adhesive resin layer (B) side of the adhesive film; and sealing the electronic component with a sealing material, wherein at least one of the adhesive resin layer (B) and the adhesive resin layer (C) is a layer whose adhesive strength decreases due to external stimuli.

2. The method for manufacturing an electronic device according to claim 1, wherein the electronic component includes a semiconductor chip.

3. The area of ​​the top surface of the electronic component is 10 mm². ２ 500mm or more ２ The method for manufacturing an electronic device according to claim 1 or 2, which is as follows:

4. A method for manufacturing an electronic device according to any one of claims 1 to 3, wherein the average distance between the multiple electronic components is 1500 μm or less.

5. A method for manufacturing an electronic device according to any one of claims 1 to 4, wherein the electronic component is rectangular and the coverage rate according to the following formula (1) is 80% or more. Coverage rate (%) = 100 × [(vertical length of one electronic component) × (horizontal length of one electronic component) × (number of electronic components)] / {[(vertical length of one electronic component) + (average spacing between electronic components)] × [(horizontal length of one electronic component) + (average spacing between electronic components)] × (number of electronic components)} ...Formula (1) 6. The method for manufacturing an electronic device according to any one of claims 1 to 5, wherein the step of reducing the amount of volatile components in the adhesive film includes a step of reducing the amount of volatile components in the adhesive film by heat treatment.

7. The method for manufacturing an electronic device according to claim 6, wherein the heating time in the step of reducing the amount of volatile components in the adhesive film by the heat treatment is 0.1 hours or more and 48 hours or less.

8. The method for manufacturing an electronic device according to claim 6 or 7, wherein the heating temperature in the step of reducing the amount of volatile components in the adhesive film by the heat treatment is 100°C or more and 150°C or less.

9. A method for manufacturing an electronic device according to any one of claims 1 to 8, further comprising the step of reducing the adhesive force of at least one of the adhesive resin layers (B) and the adhesive resin layer (C) by external stimulation.

10. The method for manufacturing an electronic device according to any one of claims 1 to 9, wherein the sealing material includes an epoxy resin-based sealing material.

11. A method for manufacturing an electronic device according to any one of claims 1 to 10, wherein at least one of the adhesive resin layer (B) and the adhesive resin layer (C) comprises one or more selected from the group consisting of heat-peelable adhesive resin layers and light-peelable adhesive resin layers.

12. The method for manufacturing an electronic device according to claim 11, wherein the heat-peelable adhesive resin layer includes an adhesive resin layer whose adhesive strength decreases or is lost when heated at a temperature exceeding 100°C.

13. A method for manufacturing an electronic device according to any one of claims 1 to 12, wherein the adhesive resin (C1) constituting the adhesive resin layer (C) includes one or more selected from the group consisting of (meth)acrylic adhesive resins, urethane adhesive resins, silicone adhesive resins, polyolefin adhesive resins, polyester adhesive resins, polyamide adhesive resins, fluorine adhesive resins, and styrene-diene block copolymer adhesive resins.

14. The method for manufacturing an electronic device according to any one of claims 1 to 13, wherein the thickness of the adhesive resin layer (C) is 1 μm or more and 500 μm or less.

15. A method for manufacturing an electronic device according to any one of claims 1 to 14, wherein the adhesive resin (B1) constituting the adhesive resin layer (B) includes 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.

16. The method for manufacturing an electronic device according to any one of claims 1 to 15, wherein the thickness of the adhesive resin layer (B) is 1 μm or more and 500 μm or less.

17. A method for manufacturing an electronic device according to any one of claims 1 to 16, further comprising an intermediate layer (D) between the base material layer (A) and the adhesive resin layer (B), and at least one of the two selected from between the base material layer (A) and the adhesive resin layer (C).

18. The method for manufacturing an electronic device according to claim 17, wherein the intermediate layer (D) includes a layer that hardens upon external stimulation.

19. The method for manufacturing an electronic device according to claim 17 or 18, wherein the intermediate layer (D) contains a crosslinking agent.

20. The method for manufacturing an electronic device according to claim 19, wherein the crosslinking agent comprises one or more selected from the group consisting of polyfunctional (meth)acrylate compounds and isocyanate compounds.

21. The method for manufacturing an electronic device according to any one of claims 17 to 20, wherein the intermediate layer (D) comprises one or more selected from the group consisting of thermal initiators and photoinitiators.

22. The method for manufacturing an electronic device according to claim 21, wherein the thermal initiator comprises one or more selected from the group consisting of aromatic ketones, onium salt compounds, organic peroxides, thio compounds, hexaarylbiimidazole compounds, ketoxime ester compounds, borate compounds, azinium compounds, metallocene compounds, active ester compounds, compounds having carbon-halogen bonds, and azo compounds.

23. The method for manufacturing an electronic device according to claim 21 or 22, wherein the photoinitiator comprises an alkylphenone-based photoinitiator.

24. The method for manufacturing an electronic device according to any one of claims 17 to 23, wherein the thickness of the intermediate layer (D) is 5 μm or more and 1000 μm or less.

25. The method for manufacturing an electronic device according to any one of claims 1 to 24, wherein the base layer (A) contains a thermoplastic resin.

26. The method for manufacturing an electronic device according to any one of claims 1 to 25, wherein the thickness of the substrate layer (A) is 1 μm or more and 500 μm or less.

27. A method for manufacturing an electronic device according to any one of claims 1 to 26, wherein the electronic device includes a fan-out type package.

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