Method for manufacturing electronic equipment

Abstract

To provide a method for manufacturing electronic equipment capable of suppressing misalignment of electronic components in an encapsulation process.SOLUTION: A method for manufacturing electronic equipment includes a process (a) to prepare a structure 100 having a base material layer 10, an adhesive film 50 provided with an adhesive resin layer (A) on a first surface side 10A of the base material layer 10 for temporarily fixing an electronic component 70 and an adhesive resin layer (B) on a second surface side 10B of the base material layer 10, multiple electronic components 70 attached to the adhesive resin layer (A) of the adhesive film 50, and a support substrate 80 attached to adhesive resin layer (B) of the adhesive film 50, and a process (b) of encapsulating the electronic component 70 with a sealing material 60, and the process (b) includes a process for covering the multiple electronic components 70 individually with the sealing material 60.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing an electronic device. [Background technology]

[0002] 2. Description of the Related Art Fan-out packages have been developed as a technology that can reduce the size and weight of electronic devices (eg, semiconductor devices). In eWLB (Embedded Wafer Level Ball Grid Array), which is one of the manufacturing methods for fan-out packages, multiple electronic components such as semiconductor chips are temporarily fixed in a spaced-apart state on an adhesive film attached to a support substrate, and the multiple electronic components are collectively sealed with a sealing material. Here, the adhesive film needs to be fixed to the electronic components and the support substrate during the sealing process, and after sealing, it needs to be removed from the sealed electronic components together with the support substrate.

[0003] As a technique relating to a manufacturing method of such a fan-out package, for example, the technique described in Patent Document 1 (JP Patent Publication No. 2011-134811) can be given.

[0004] Patent Document 1 describes a heat-resistant adhesive sheet for semiconductor device manufacturing that is attached when resin-sealing a substrate-less semiconductor chip, as a method for solving the problem of the chip not being held in place due to pressure during resin sealing and shifting from the designated position, or the problem of the package being damaged due to the sealing material hardening or heat causing the sealing material to become strongly adhesive to the chip surface when the heat-resistant adhesive sheet for semiconductor device manufacturing is peeled off, the heat-resistant adhesive sheet having a base layer and an adhesive layer, the adhesive layer having an adhesive strength to SUS304 of 0.5 N / 20 mm or more after lamination, and hardening due to stimuli received before the resin sealing process is completed, so that the peel strength to the package is 2.0 N / 20 mm or less. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2011-134811 A Summary of the Invention [Problem to be solved by the invention]

[0006] When electronic components are placed on an adhesive film and sealed with a sealant, the electronic components may become misaligned (hereinafter, also referred to as misalignment of the electronic components). The present invention has been made in view of the above circumstances, and provides a method for manufacturing an electronic device that is capable of suppressing misalignment of electronic components during the sealing process. [Means for solving the problem]

[0007] The present inventors have conducted extensive research to achieve the above object, and as a result, have found that it is possible to suppress misalignment of electronic components during a sealing process by individually sealing a plurality of electronic components on an adhesive film, and have completed the present invention.

[0008] [1] an adhesive film including a base layer, an adhesive resin layer (A) provided on a first surface side of the base layer and for temporarily fixing an electronic component, and an adhesive resin layer (B) provided on a second surface side of the base layer; A plurality of electronic components attached to the adhesive resin layer (A) of the adhesive film; A step (a) of preparing a structure including a support substrate attached to the adhesive resin layer (B) of the adhesive film; (b) sealing the electronic component with a sealing material; Including, The method for manufacturing an electronic device, wherein the step (b) includes a step of individually covering each of the plurality of electronic components with a sealing material. [2] The method for producing an electronic device according to the above-mentioned [1], wherein the step (b) comprises a step of individually covering each of the plurality of electronic components with the sealing material by using one or more methods selected from the group consisting of a 3D printer method, a spray method, a screen printing method and an inkjet method. [3] The method for producing an electronic device according to the above [1] or [2], wherein the sealing material comprises an epoxy resin-based sealing material. [4] The method for producing an electronic device according to any one of the above [1] to [3], wherein the sealing temperature in the step (b) is 10° C. or higher and 45° C. or lower. [5] The method for producing an electronic device according to any one of [1] to [4] above, further comprising, after step (b), step (c) of curing the sealing material by one or two methods selected from the group consisting of light irradiation and heat treatment. [6] The method for producing an electronic device according to [5] above, further comprising, after step (c), a step (d) of applying an external stimulus to the adhesive resin layer (B) to reduce the adhesive strength of the adhesive resin layer (B) and peeling off the support substrate from the structure. [7] The method for producing an electronic device according to [6] above, further comprising, after step (d), a step (e) of peeling the adhesive film from the plurality of electronic components. [8] The method for producing an electronic device according to any one of the above [1] to [7], wherein the adhesive resin layer (A) contains an adhesive resin (A1). [9] The method for producing an electronic device according to [8] above, wherein the adhesive resin (A1) 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.

[10] The method for producing an electronic device according to the above [8] or [9], wherein the adhesive resin layer (A) further contains a crosslinking agent (A2) having two or more crosslinkable functional groups in one molecule.

[11] The method for producing an electronic device according to the above

[10] , wherein the content of the crosslinking agent (A2) is from 0.1 to 15 parts by mass per 100 parts by mass of the adhesive resin (A1).

[12] The method for producing an electronic device according to any one of the above [1] to

[11] , wherein the adhesive resin layer (B) contains a thermally expandable adhesive.

[13] The method for producing an electronic device according to

[12] above, wherein the thermally expandable adhesive is an adhesive whose adhesive strength is reduced or lost when heated at a temperature exceeding 150°C.

[14] The method for producing an electronic device according to any one of the above [1] to

[13] , wherein the support substrate comprises at least one substrate selected from the group consisting of a stainless steel substrate and a glass substrate.

[15] The method for producing an electronic device according to any one of the above [1] to

[14] , wherein the step (a) includes a step (a-1) of adhering the adhesive film onto the supporting substrate so that the adhesive resin layer (B) faces the supporting substrate.

[16] The method for producing an electronic device according to

[15] above, wherein the step (a) further comprises a step (a-2) of obtaining the structure by arranging the plurality of electronic components on the adhesive resin layer (A) of the adhesive film attached to the support substrate.

[17] The method for producing an electronic device according to any one of the above [1] to

[16] , wherein in the step (a), the distance between the plurality of electronic components is 10 μm or more and 10 mm or less.

[18] The method for producing an electronic device according to any one of the above [1] to

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

[0009] According to the present invention, it is possible to provide a method for manufacturing an electronic device that is capable of suppressing misalignment of electronic components during a sealing process. [Brief description of the drawings]

[0010] [Figure 1] 1 is a cross-sectional view showing a schematic example of a structure of an adhesive film according to an embodiment of the present invention. [Diagram 2] 1A to 1C are cross-sectional views illustrating an example of a method for manufacturing an electronic device according to an embodiment of the present invention. [Diagram 3] 1A to 1C are cross-sectional views illustrating an example of a method for manufacturing an electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In all the drawings, the same components are denoted by the same reference numerals, and the description thereof will be omitted as appropriate. In addition, the drawings are schematic views, and the actual dimensional ratios are not necessarily the same. In the present specification, unless otherwise specified, the upper and lower limit values ​​of a numerical range can be arbitrarily combined. In the present specification, "(meth)acrylic" means acrylic, methacrylic, or both acrylic and methacrylic.

[0012] <Electronic device manufacturing method> A method for manufacturing the electronic device of this embodiment will be described below. Figures 2 and 3 are cross-sectional views that typically show an example of a method for manufacturing the electronic device of this embodiment. The manufacturing method for an electronic device of this embodiment includes a step (a) of preparing a structure 100 including a base layer 10, an adhesive film 50 including an adhesive resin layer (A) provided on the first surface 10A of the base layer 10 for temporarily fixing electronic components, and an adhesive resin layer (B) provided on the second surface 10B of the base layer 10, a plurality of electronic components 70 attached to the adhesive resin layer (A) of the adhesive film 50, and a support substrate 80 attached to the adhesive resin layer (B) of the adhesive film 50, and a step (b) of sealing the electronic components 70 with a sealing material 60, where the step (b) includes a step of individually covering each of the plurality of electronic components 70 with the sealing material 60.

[0013] According to the manufacturing method of the electronic device of the present embodiment, it is possible to suppress the displacement of the electronic components during the sealing process by covering each of the electronic components individually with a sealing material. Furthermore, according to the manufacturing method of the electronic device of the present embodiment, it is possible to suppress the displacement of the electronic components and wiring when performing the rewiring process, which is caused by the electronic components being moved to a location different from the initial arrangement of the electronic components, and to prevent a decrease in reliability such as disconnection. Furthermore, according to the manufacturing method of the electronic device of the present embodiment, it is possible to eliminate the need for a process of re-dividing the electronic components into individual packages after sealing by covering each of the electronic components individually with a sealing material, and it is expected to simplify the process and reduce the environmental load by reducing the amount of sealing material used during molding.

[0014] In a conventional method for manufacturing a fan-out type package, electronic components such as chips are arranged in a spaced state on a double-sided tape attached to a substrate or on a temporary fixing material (adhesive, wax, etc.) formed on the substrate, and a sealing material such as an epoxy resin is flowed in a vacuum device by a compression method or a transfer method to seal them all at once, or a sheet-like sealing material is attached to seal them. In this process, after mounting electronic components on a temporary fixing material such as a double-sided tape or an adhesive, the sealing material is heated and melted and flowed at high pressure to seal them. Therefore, the electronic components are displaced due to thermal contraction and expansion of the double-sided tape or the temporary fixing material, or the electronic components are pushed laterally by the sealing material and move a small distance. This displacement of the electronic components causes the electronic components to move to a location different from the initial electronic component placement. As a result, the wiring is displaced when a rewiring process is performed, which may lead to a decrease in reliability, such as disconnection. In addition, in the conventional manufacturing method of fan-out type packages, the entire electronic components are encapsulated at once, which requires a process to separate each package again after encapsulation. As a result, not only does the manufacturing process of electronic devices become complicated, but molding encapsulant on unnecessary parts also places a high burden on the environment. On the other hand, in the electronic device manufacturing method of the present embodiment, since the electronic components are individually covered with the sealing material, no lateral force is generated by the sealing material applied to the electronic components as in the conventional fan-out package manufacturing method. As described above, the electronic device manufacturing method of the present embodiment makes it possible to suppress the displacement of the electronic components in the sealing process. Furthermore, the electronic device manufacturing method of the present embodiment suppresses the displacement of the electronic components and the wiring when the rewiring process is performed, which is caused by the electronic components being moved to a location different from the initial electronic component arrangement, and prevents a decrease in reliability such as disconnection. In addition, the electronic device manufacturing method of this embodiment molds the encapsulant only in the necessary areas around the electronic components. This makes it possible to omit the process of re-dividing the packages after sealing. As described above, the electronic device manufacturing method of this embodiment is expected to simplify the process and reduce the environmental impact by reducing the amount of encapsulant used during molding.

[0015] Each step of the method for manufacturing an electronic device according to this embodiment will now be described.

[0016] [Process (a)] In step (a), a structure 100 is prepared, which includes a base layer 10, an adhesive film 50 including an adhesive resin layer (A) provided on the first surface 10A of the base layer 10 for temporarily fixing electronic components, and an adhesive resin layer (B) provided on the second surface 10B of the base layer 10, a plurality of electronic components 70 attached to the adhesive resin layer (A) of the adhesive film 50, and a support substrate 80 attached to the adhesive resin layer (B) of the adhesive film 50.

[0017] From the viewpoint of further suppressing displacement of the electronic components during the sealing process, the support substrate 80 preferably includes at least one type selected from the group consisting of a stainless steel substrate and a glass substrate.

[0018] The step (a) preferably includes a step (a-1) of adhering the adhesive film 50 onto the support substrate 80 so that the adhesive resin layer (B) faces the support substrate 80. A protective film called a separator may be attached onto the adhesive resin layer (B), and the exposed surface of the adhesive resin layer (B) can be attached to the surface of the support substrate 80 by peeling off the protective film.

[0019] In addition, it is preferable that the step (a) further includes a step (a-2) of obtaining a structure 100 by arranging a plurality of electronic components 70 on the adhesive resin layer (A) of the adhesive film 50 attached to the support substrate 80. Examples of the electronic component 70 include semiconductor chips such as ICs, LSIs, discrete devices, light-emitting diodes, and light-receiving elements, semiconductor panels, and semiconductor packages. The surface of the electronic component 70 has an uneven structure due to, for example, the presence of electrodes. Furthermore, for example, when mounting an electronic device on a mounting surface, the electrodes are joined to electrodes formed on the mounting surface to form an electrical connection between the electronic device and the mounting surface (the mounting surface of a printed circuit board or the like). Examples of the electrodes include bump electrodes such as ball bumps, printed bumps, stud bumps, plated bumps, and pillar bumps. That is, the electrodes are usually convex electrodes. These bump electrodes may be used alone or in combination of two or more types. The metal species constituting the bump electrode is not particularly limited, and examples thereof include silver, gold, copper, tin, lead, bismuth, and alloys thereof. These metal species may be used alone or in combination of two or more.

[0020] The lower limit of the distance between the electronic components 70 is preferably 10 μm or more, more preferably 15 μm or more, even more preferably 20 μm or more, and even more preferably 25 μm or more. By making the distance between the electronic components 70 equal to or more than the lower limit, the electronic components can be sealed individually more effectively in the sealing step. Furthermore, the upper limit of the distance between the multiple electronic components 70 can be appropriately determined depending on the performance required of the electronic device, and is, for example, 10 mm or less, 1 mm or less, 100 μm or less, or 50 μm or less.

[0021] [Step (b)] In step (b), the electronic components 70 are sealed with the sealing material 60. Step (b) includes a step of covering each of the multiple electronic components 70 with the sealing material 60 individually.

[0022] As a method for individually covering each of the plurality of electronic components 70 with the sealing material 60, it is preferable to use one or more methods selected from the group consisting of a 3D printer method, a spray method, a screen printing method, and an inkjet method, and it is more preferable to use a 3D printer method. That is, the step (b) of the manufacturing method of the electronic device of this embodiment preferably includes a step of individually covering each of the plurality of electronic components 70 with the sealing material 60 using one or more methods selected from the group consisting of a 3D printer method, a spray method, a screen printing method, and an inkjet method, and it is more preferable to include a step of individually covering each of the plurality of electronic components 70 with the sealing material 60 using the 3D printer method.

[0023] The 3D printer method is a method in which a 3D printer is used to print the encapsulant 60 individually onto each of the electronic components 70, thereby coating each of the electronic components 70 individually with the encapsulant 60. The spray method is a method in which the sealing material is sprayed in fine mist form onto each of the electronic components 70 individually, thereby coating each of the electronic components 70 with the sealing material 60 individually. The screen printing method is a method in which the sealing material is applied to a screen mask, and then the sealing material 60 is printed individually onto each of the multiple electronic components 70 using a squeegee, thereby coating each of the multiple electronic components 70 individually with the sealing material 60. The inkjet method is a method in which the sealant 60 is sprayed from an inkjet head and printed individually onto each of the electronic components 70, thereby coating each of the electronic components 70 with the sealant 60 individually.

[0024] By including in the step (b) a step of individually covering each of the plurality of electronic components 70 with the sealing material 60 using the above-mentioned method, it is possible to suppress displacement of the electronic components during the sealing step. This is because the above method allows the encapsulant to be formed in any shape on the electronic components at room temperature and normal pressure. The above method allows the encapsulant to be molded without a heating process, so that thermal contraction and expansion of the double-sided tape and temporary fixing material can be suppressed. In addition, since there is no pressing process or transfer process in which the encapsulant flows at high temperature and high pressure, no lateral force is applied to the electronic components by the encapsulant. This makes it possible to suppress the displacement of the electronic components in the encapsulation process. Furthermore, it is possible to suppress the displacement of the electronic components and wiring when performing the rewiring process, which is caused by the electronic components being moved to a location different from the initial electronic component placement, and to prevent a decrease in reliability such as disconnection. Furthermore, according to the above method, the encapsulant can be molded only in the necessary areas around the periphery of the electronic components. Therefore, the process of re-dividing the packages after encapsulation can be omitted. As described above, according to the manufacturing method for electronic devices of this embodiment, it is expected that the environmental load will be reduced by simplifying the process and reducing the amount of encapsulant used during molding.

[0025] As the sealing material 60, any known sealing material can be used as long as it has high insulating properties. However, the sealing material 60 preferably includes an epoxy resin-based sealing material, since this improves the affinity of the sealing material 60 to the adhesive film 50 and enables the electronic components 70 to be sealed more evenly. As such an epoxy resin-based sealing material, for example, T693 / R4000 series, T693 / R1000 series, T693 / R5000 series, etc. manufactured by Nagase ChemteX Corporation can be used. The state of the sealing material 60 may be solid or liquid, but it is preferable that the sealing material 60 be liquid, from the viewpoint of enabling the sealing process to be carried out at low temperature and pressure and further suppressing displacement of electronic components during the sealing process.

[0026] The lower limit of the viscosity of the sealing material 60 measured using a BF type viscometer while stirring at a temperature of 25°C and a shear rate of 5 rpm is not particularly limited, and is, for example, 1 mPa·s or more, 10 mPa·s or more, 20 mPa·s or more, or 30 mPa·s or more. Moreover, the upper limit of the viscosity of the sealing material 60 measured using a BF type viscometer while stirring at a temperature of 25°C and a shear rate of 5 rpm is preferably 400 Pa·s or less, more preferably 300 Pa·s or less, even more preferably 200 Pa·s or less, and even more preferably 100 Pa·s or less, from the viewpoint of further suppressing displacement of electronic components.

[0027] The lower limit of the thickness of the sealing material 60 after covering the electronic component 70 is, from the viewpoint of further suppressing misalignment of the electronic component, preferably 1.0 μm or more, more preferably 1.5 μm or more, even more preferably 5.0 μm or more, even more preferably 10.0 μm or more, even more preferably 30.0 μm or more, and even more preferably 50.0 μm or more. Furthermore, the upper limit of the thickness of the sealing material 60 after covering the electronic components 70 is preferably 2.0 mm or less, more preferably 1.5 mm or less, even more preferably 1.0 mm or less, and even more preferably 0.5 mm or less, from the viewpoint of further suppressing misalignment of the electronic components.

[0028] From the viewpoint of the working efficiency of step (b), the lower limit of the sealing temperature in step (b) is preferably 10° C. or more, more preferably 15° C. or more, and even more preferably 20° C. or more. Moreover, from the viewpoint of further suppressing the displacement of the electronic components, the upper limit of the sealing temperature in step (b) is preferably 45° C. or less, more preferably 40° C. or less, even more preferably 35° C. or less, and even more preferably 30° C. or less. In this embodiment, the sealing temperature refers to the set temperature of the device used to seal the electronic component 70.

[0029] From the viewpoint of improving the reliability of the electronic device, the lower limit of the sealing pressure in step (b) is preferably 30 kPa or more, more preferably 50 kPa or more, even more preferably 70 kPa or more, and even more preferably 90 kPa or more. From the viewpoint of further suppressing the positional deviation of the electronic components, the upper limit of the sealing pressure in step (b) is preferably 150 kPa or less, more preferably 130 kPa or less, and even more preferably 110 kPa or less. It is further preferable that the sealing pressure in step (b) is normal pressure. In the present embodiment, the sealing pressure refers to the set pressure in the device used to seal the electronic component 70.

[0030] [Process (c)] The method for manufacturing an electronic device according to the present embodiment preferably further includes a step (c) of curing the encapsulant 60 by one or two methods selected from the group consisting of light irradiation and heat treatment. In the step (c), the encapsulant 60 in the structure 100 is treated by one or two methods selected from the group consisting of light irradiation and heat treatment, thereby allowing the encapsulant 60 to be cured. This makes it possible to fix the electronic components and further suppress displacement of the electronic components. Furthermore, in the method for manufacturing an electronic device of this embodiment, a structure can be formed while curing is proceeding layer by layer, and from the viewpoint of further suppressing misalignment of electronic components, it is more preferable that the method further includes a step (c) of curing the sealing material 60 by treating it with light irradiation.

[0031] The light irradiation is preferably performed by irradiating the sealing material 60 with light such as ultraviolet light, thereby crosslinking and curing the sealing material 60. The light source used is not particularly limited, but it is preferable to use a light source capable of irradiating ultraviolet light containing a wavelength component capable of exciting the photoinitiator, and it is more preferable to use a light source capable of irradiating ultraviolet light containing a component with a wavelength of less than 300 nm. Examples of such light sources include a high-pressure mercury lamp, a low-pressure mercury lamp, a metal halide lamp, and a super UV lamp. The light irradiated by the light source may contain a component with a wavelength of 300 nm or more. In the case of ultraviolet crosslinking, for example, in an environment of 0 to 60°C, ultraviolet rays with a main wavelength of 365 nm are irradiated using a high-pressure mercury lamp at an irradiation intensity of 10 to 350 mW / cm 2 UV dose 100-20000mJ / cm 2 By irradiating the sealing material 60 under the above conditions, the sealing material 60 can be crosslinked and hardened.

[0032] The heat treatment preferably includes thermal crosslinking using an oven, thermal crosslinking using a hot plate, thermal crosslinking by infrared irradiation, etc. In the case of thermal crosslinking, the heating temperature is, for example, 100°C to 180°C, and the heat treatment time is, for example, 10 to 180 minutes. It is preferable that the heating temperature does not exceed the temperature at which gas contained in the adhesive film 50 described below is generated or the temperature at which the heat-expandable microspheres thermally expand.

[0033] [Step (d)] In the manufacturing method for the electronic device of this embodiment, it is preferable to further include, after step (c), a step (d) of applying an external stimulus to the adhesive resin layer (B) to reduce the adhesive strength of the adhesive resin layer (B) and peeling off the support substrate 80 from the structure 100. The support substrate 80 can be easily removed from the adhesive film 50, for example, by sealing the electronic components 70 and then heating the support substrate 80 to a temperature exceeding 150°C or a temperature exceeding 170°C to reduce the adhesive strength of the adhesive resin layer (B).

[0034] [Step (e)] In the method for producing an electronic device of the present embodiment, it is preferable to further include, after step (d), a step (e) of peeling the adhesive film 50 from the plurality of electronic components 70. Through this step, the electronic device 200 is obtained. Methods for peeling the adhesive film 50 from the electronic component 70 include, for example, a mechanical peeling method, a method in which the adhesive strength of the surface of the adhesive film 50 is reduced before peeling, and the like.

[0035] (Other processes) The method for manufacturing an electronic device of this embodiment may further include a step (f) 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 includes pads (not shown) that are external connection terminals formed on the outermost surface, and wiring (not shown) that electrically connects the exposed electronic components 70 to the pads. The wiring layer 310 can be formed by a conventionally known method, and may have a multi-layer 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 that are external connection terminals of the wiring layer 310 and heating the solder to melt (reflow). The gold bumps can be formed by ball bonding, plating, Au ball transfer, or other methods.

[0038] <Adhesive film> Next, the adhesive film 50 of the present embodiment will be described. FIG. 1 is a cross-sectional view that illustrates an example of the structure of an adhesive film 50 according to an embodiment of the present invention.

[0039] The adhesive film 50 of this embodiment comprises a base layer 10, an adhesive resin layer (A) provided on the first surface 10A of the base layer 10 for temporarily fixing an electronic component, and an adhesive resin layer (B) provided on the second surface 10B of the base layer 10.

[0040] The lower limit of the total thickness of the adhesive film 50 of this embodiment is preferably 10 μm or more, and more preferably 20 μm or more, from the viewpoint of the balance between mechanical properties and handleability. The upper limit of the total thickness of the adhesive film 50 of this embodiment is preferably 1000 μm or less, and more preferably 500 μm or less, from the viewpoint of the balance between mechanical properties and ease of handling.

[0041] Next, each layer constituting the adhesive film 50 of this embodiment will be described.

[0042] [Base material layer] The base layer 10 is a layer provided for the purpose of improving the properties of the adhesive film 50, such as handleability, mechanical properties, and heat resistance. The base layer 10 is not particularly limited, but may be, for example, a resin film. Examples of resins constituting the resin film include known thermoplastic resins, such as polyolefins such as polyethylene, polypropylene, poly(4-methyl-1-pentene), and poly(1-butene); polyesters such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polyamides such as nylon-6, nylon-66, and polymetaxylene adipamide; polyacrylates; polymethacrylates; polyvinyl chloride; polyvinylidene chloride; polyimides; polyetherimides; ethylene-vinyl acetate copolymers; polyacrylonitrile; polycarbonates; polystyrenes; ionomers; polysulfones; polyethersulfones; and polyphenylene ethers. Among these, from the viewpoint of an excellent balance of transparency, mechanical strength, price, and the like, one or more selected from polypropylene, polyethylene terephthalate, polyethylene naphthalate, polyamide, and polyimide are preferred, and at least one selected from polyethylene terephthalate and polyethylene naphthalate is more preferred.

[0043] The substrate layer 10 may be a single layer or two or more layers. The resin film used to form the base layer 10 may be in the form of a stretched film or a uniaxially or biaxially stretched film. From the viewpoint of improving the mechanical strength of the base layer 10, however, a uniaxially or biaxially stretched film is preferable.

[0044] The lower limit of the thickness of the base layer 10 is preferably 1 μm or more, more preferably 5 μm or more, and even more preferably 10 μm or more, from the viewpoint of obtaining good film properties. Moreover, the upper limit of the thickness of the base layer 10 is preferably 500 μm or less, more preferably 300 μm or less, and even more preferably 250 μm or less, from the viewpoint of obtaining good film properties. The substrate layer 10 may be subjected to a surface treatment in order to improve adhesion to other layers. Specifically, corona treatment, plasma treatment, undercoat treatment, primer coat treatment, etc. may be performed.

[0045] [Adhesive resin layer (A)] The adhesive resin layer (A) is a layer provided on one surface side of the base layer 10. The adhesive resin layer (A) is a layer for temporarily fixing an electronic component by contacting the surface of the electronic component when the electronic component is sealed with a sealing material in a manufacturing process of an electronic device, for example.

[0046] The adhesive resin layer (A) preferably contains an adhesive resin (A1). The adhesive resin (A1) preferably contains one or more selected from the group consisting of (meth)acrylic adhesive resins (p), silicone adhesive resins, urethane adhesive resins, olefin adhesive resins and styrene adhesive resins. Among these, the (meth)acrylic adhesive resin (p) is preferred from the viewpoint of easily adjusting the adhesive strength.

[0047] The adhesive resin layer (A) may be a radiation-crosslinked adhesive resin layer whose adhesive strength can be reduced by radiation. When the radiation-crosslinked adhesive resin layer is irradiated with radiation, crosslinking occurs and the adhesive strength is significantly reduced, making it easier to peel the adhesive film 50 from the electronic component. Examples of radiation include ultraviolet rays, electron beams, and infrared rays. The radiation crosslinkable adhesive resin layer is preferably an ultraviolet crosslinkable adhesive resin layer.

[0048] The (meth)acrylic adhesive resin (p) used in the adhesive resin layer (A) may be, for example, a copolymer containing a (meth)acrylic acid alkyl ester monomer unit (p1) and a monomer unit (p2) having a functional group capable of reacting with a crosslinking agent. In this embodiment, the (meth)acrylic acid alkyl ester means an acrylic acid alkyl ester, a methacrylic acid alkyl ester, or a mixture thereof.

[0049] The (meth)acrylic adhesive resin (p) of this embodiment can be obtained, for example, by copolymerizing a monomer mixture containing a (meth)acrylic acid alkyl ester monomer (p1) and a monomer (p2) having a functional group capable of reacting with a crosslinking agent.

[0050] The monomer (p1) forming the (meth)acrylic acid alkyl ester monomer unit (p1) includes a (meth)acrylic acid alkyl ester having an alkyl group with about 1 to 12 carbon atoms. A (meth)acrylic acid alkyl ester having an alkyl group with 1 to 8 carbon atoms is preferable. Specific examples include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, etc. These may be used alone or in combination of two or more. In the (meth)acrylic adhesive resin (p) of the present embodiment, the lower limit of the content of the (meth)acrylic acid alkyl ester monomer unit (p1) is preferably 10 mass % or more, more preferably 50 mass % or more, and even more preferably 85 mass % or more, when the sum of all monomer units in the (meth)acrylic adhesive resin (p) is taken as 100 mass %, from the viewpoint of further suppressing misalignment of electronic components in the sealing step. In the (meth)acrylic adhesive resin (p) of the present embodiment, the upper limit of the content of the (meth)acrylic acid alkyl ester monomer unit (p1) is preferably 98.9% by mass or less, more preferably 97% by mass or less, and even more preferably 95% by mass or less, when the sum of all monomer units in the (meth)acrylic adhesive resin (p) is taken as 100% by mass, from the viewpoint of further suppressing misalignment of electronic components in the sealing step.

[0051] Examples of the monomer (p2) that forms the monomer unit (p2) having a functional group that can react with a crosslinking agent include acrylic acid, methacrylic acid, itaconic acid, mesaconic acid, citraconic acid, fumaric acid, maleic acid, itaconic acid monoalkyl ester, mesaconic acid monoalkyl ester, citraconic acid monoalkyl ester, fumaric acid monoalkyl ester, maleic acid monoalkyl ester, acrylate, methacrylate, 2-hydroxyethyl acrylate, methacrylate, acrylamide, methacrylamide, tertiary-butylaminoethyl acrylate, tertiary-butylaminoethyl methacrylate, etc. Preferred are acrylic acid, methacrylic acid, acrylate, 2-hydroxyethyl acrylate, methacrylate, acrylamide, methacrylamide, etc. These may be used alone or in combination of two or more. In the (meth)acrylic adhesive resin (p) of the present embodiment, the upper limit of the content of the monomer unit (p2) is preferably 40 mass% or less, more preferably 20 mass% or less, and even more preferably 10 mass% or less, when the sum of all monomer units in the (meth)acrylic adhesive resin (p) is taken as 100 mass%, from the viewpoint of further suppressing misalignment of electronic components in the sealing step. The lower limit is not particularly limited, but is, for example, 1 mass % or more.

[0052] The (meth)acrylic adhesive resin (p) of this embodiment may further contain, in addition to the monomer unit (p1) and the monomer unit (p2), a bifunctional monomer unit (p3) or a specific comonomer unit having surfactant properties (hereinafter referred to as a polymerizable surfactant). The polymerizable surfactant has the property of copolymerizing with the monomers (p1), (p2) and (p3), and also acts as an emulsifier in the case of emulsion polymerization.

[0053] Examples of the monomer (p3) forming the bifunctional monomer unit (p3) include allyl methacrylate, allyl acrylate, divinylbenzene, vinyl methacrylate, vinyl acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tetraethylene glycol di(meth)acrylate, and, for example, those having diacrylate or dimethacrylate at both ends and a main chain structure of propylene glycol type (e.g., manufactured by Nippon Oil & Fats Corporation, trade names: PDP-200, PDP-400, ADP-200, ADP-400), tetramethylene glycol type (e.g., manufactured by Nippon Oil & Fats Corporation, trade names: ADT-250, ADT-850) and mixed types thereof (e.g., manufactured by Nippon Oil & Fats Corporation, trade names: ADET-1800, ADPT-4000).

[0054] In the (meth)acrylic adhesive resin (p) of this embodiment, the upper limit of the content of the monomer unit (p3) is preferably 30 mass% or less, more preferably 20 mass% or less, even more preferably 15 mass% or less, and particularly preferably 5 mass% or less, when the sum of all monomer units in the (meth)acrylic adhesive resin (p) is taken as 100 mass%, from the viewpoint of further suppressing misalignment of electronic components in the sealing step. The lower limit is not particularly limited, but is, for example, 0.1 mass % or more.

[0055] Examples of polymerizable surfactants include those in which a polymerizable 1-propenyl group has been introduced into the benzene ring of polyoxyethylene nonylphenyl ether (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.; trade names: Aqualon RN-10, RN-20, RN-30, RN-50, etc.), those in which a polymerizable 1-propenyl group has been introduced into the benzene ring of an ammonium salt of a sulfate ester of polyoxyethylene nonylphenyl ether (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.; trade names: Aqualon HS-10, HS-20, HS-1025, etc.), and sulfosuccinic acid diesters having a polymerizable double bond in the molecule (manufactured by Kao Corporation; trade names: Latemul S-120A, S-180A, etc.). In the (meth)acrylic adhesive resin (p) of the present embodiment, the upper limit of the content of the polymerizable surfactant is preferably 30 mass % or less, more preferably 20 mass % or less, even more preferably 15 mass % or less, and even more preferably 5 mass % or less, when the sum of all monomer units in the (meth)acrylic adhesive resin (p) is taken as 100 mass %, from the viewpoint of further suppressing misalignment of electronic components in the sealing step. The lower limit is not particularly limited, but is, for example, 0.1 mass % or more.

[0056] The (meth)acrylic adhesive resin (p) of the present embodiment may further contain, as necessary, a monomer unit formed from a monomer having a polymerizable double bond, such as vinyl acetate, acrylonitrile, or styrene.

[0057] The polymerization reaction mechanism of the (meth)acrylic adhesive resin (p) of the present embodiment may be radical polymerization, anionic polymerization, cationic polymerization, etc. Considering the production cost of the (meth)acrylic adhesive resin (p), the effect of the functional group of the monomer, the effect of ions on the surface of the electronic component, etc., it is preferable to polymerize by radical polymerization. When polymerizing by radical polymerization reaction, the following radical polymerization initiators are used: benzoyl peroxide, di-t-butyl peroxide, dicumyl peroxide, 3,3,5-trimethylhexanoyl peroxide, di-2-ethylhexyl peroxydicarbonate, methyl ethyl ketone peroxide, t-butyl peroxyphthalate, t-butyl peroxybenzoate, di-t-butyl peroxyacetate, t-butyl peroxyisobutyrate, t-butyl peroxy-2-hexanoate, t-butyl peroxy Examples of the peroxides include organic peroxides such as 2-ethylhexanoate, t-butylperoxy-3,5,5-trimethylhexanoate, acetyl peroxide, isobutyryl peroxide, octanoyl peroxide, t-butyl peroxide, and di-t-amyl peroxide; inorganic peroxides such as ammonium persulfate, potassium persulfate, and sodium persulfate; and azo compounds such as 2,2'-azobisisobutyronitrile, 2,2'-azobis-2-methylbutyronitrile, and 4,4'-azobis-4-cyanovaleric acid.

[0058] When polymerization is performed by emulsion polymerization, among these radical polymerization initiators, inorganic peroxides such as water-soluble ammonium persulfate, potassium persulfate, and sodium persulfate, and azo compounds having a carboxyl group in the molecule such as water-soluble 4,4'-azobis-4-cyanovaleric acid are preferred. Considering the influence of ions on the surface of electronic components, azo compounds having a carboxyl group in the molecule such as ammonium persulfate and 4,4'-azobis-4-cyanovaleric acid are more preferred, and azo compounds having a carboxyl group in the molecule such as 4,4'-azobis-4-cyanovaleric acid are particularly preferred.

[0059] The adhesive resin layer (A) of the present embodiment preferably further contains, in addition to the adhesive resin (A1), a crosslinking agent (A2) having two or more crosslinkable functional groups in one molecule. The crosslinking agent (A2) having two or more crosslinkable functional groups in one molecule can be used to adjust the adhesive strength and cohesive strength by reacting with the functional groups of the adhesive resin (A1). Examples of such crosslinking agents (A2) include epoxy compounds such as sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, glycerol polyglycidyl ether, neopentyl glycol diglycidyl ether, and resorcin diglycidyl ether; isocyanate compounds such as tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate triadduct of trimethylolpropane, polyisocyanate, diphenylmethane diisocyanate, and tolylene diisocyanate; and trimethylolpropane-tri-β-aziridinylpropionate. aziridine-based compounds such as N,N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxamide), N,N'-hexamethylene-1,6-bis(1-aziridinecarboxamide), N,N'-toluene-2,4-bis(1-aziridinecarboxamide), and trimethylolpropane-tri-β-(2-methylaziridine)propionate; tetrafunctional epoxy-based compounds such as N,N,N',N'-tetraglycidyl-m-xylylenediamine and 1,3-bis(N,N'-diglycidylaminomethyl)cyclohexane; and melamine-based compounds such as hexamethoxymethylolmelamine. These may be used alone or in combination of two or more. Among these, it is preferable to contain one or more compounds selected from the group consisting of epoxy compounds, isocyanate compounds, and aziridine compounds.

[0060] The content of the crosslinking agent (A2) is usually preferably within a range in which the number of functional groups in the crosslinking agent (A2) is not greater than the number of functional groups in the adhesive resin (A1). However, if necessary, an excess of the crosslinking agent (A2) may be contained when new functional groups are generated by the crosslinking reaction or when the crosslinking reaction is slow. The lower limit of the content of the crosslinking agent (A2) in the adhesive resin layer (A) is preferably 0.1 parts by mass or more, and more preferably 0.5 parts by mass or more, per 100 parts by mass of the adhesive resin (A1), from the viewpoint of improving the balance between the heat resistance and adhesion of the adhesive resin layer (A). In addition, the upper limit of the content of the crosslinking agent (A2) in the adhesive resin layer (A) is preferably 15 parts by mass or less, and more preferably 10 parts by mass or less, per 100 parts by mass of the adhesive resin (A1), from the viewpoint of improving the balance between the heat resistance and adhesion of the adhesive resin layer (A).

[0061] The adhesive resin layer (A) may contain additives such as plasticizers and tackifier resins as other components. When the adhesive resin layer (A) is a radiation crosslinking adhesive resin layer, it may contain various additives for radiation crosslinking. The total content of the adhesive resin (A1) and the crosslinking agent (A2) in the adhesive resin layer (A) is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 90% by mass or more, and particularly preferably 95% by mass or more, when the entire adhesive resin layer (A) is taken as 100% by mass. This can further suppress adhesive residue on the electronic component side when the adhesive film is peeled off from the electronic component. The upper limit is not particularly limited, but is, for example, 100% by mass or less.

[0062] The adhesive resin layer (A) may be a single layer or multiple layers. The lower limit of the thickness of the adhesive resin layer (A) is preferably 1 μm or more, more preferably 3 μm or more, from the viewpoint of improving adhesiveness and thermal peelability. From the viewpoint of improving the handleability of the adhesive film 50, the upper limit of the thickness of the adhesive resin layer (A) is preferably 100 μm or less, more preferably 50 μm or less.

[0063] The adhesive resin layer (A) can be formed, for example, by applying an adhesive onto the base layer 10. The adhesive may be dissolved in a solvent and applied as a coating liquid, or may be applied as a water-based emulsion, or the liquid adhesive may be directly applied. Among them, the aqueous emulsion coating liquid is preferable. Examples of the aqueous emulsion coating liquid include coating liquids in which a (meth)acrylic adhesive resin (p), a silicone adhesive resin, a urethane adhesive resin, an olefin adhesive resin, a styrene adhesive resin, or the like is dispersed in water. A pressure-sensitive adhesive coating solution dissolved in an organic solvent may be used. The organic solvent is not particularly limited, and may be appropriately selected from known solvents in consideration of solubility and drying time. Examples of organic solvents include esters such as ethyl acetate and methyl acetate; ketones such as acetone and MEK; aromatics such as benzene, toluene, and ethylbenzene; linear or cyclic aliphatics such as heptane, hexane, and cyclohexane; and alcohols such as isopropanol and butanol. Ethyl acetate and toluene are preferred as organic solvents. These solvents may be used alone or in combination of two or more.

[0064] The adhesive coating liquid can be coated by a conventional coating method such as a roll coater method, a reverse roll coater method, a gravure roll method, a bar coat method, a comma coater method, a die coater method, etc. There is no particular restriction on the drying conditions of the coated adhesive, but it is generally preferable to dry the coated adhesive at a temperature range of 80 to 200°C for 10 seconds to 10 minutes. It is more preferable to dry the coated adhesive at 80 to 170°C for 15 seconds to 5 minutes. In order to sufficiently promote the crosslinking reaction between the crosslinking agent and the adhesive, the adhesive coating liquid may be heated at 40 to 80°C for about 5 to 300 hours after drying is completed.

[0065] The base material layer 10 and the adhesive resin layer (A) may be formed by co-extrusion, or may be formed by laminating a film-like base material layer 10 and a film-like adhesive resin layer (A). In the examples described later, the adhesive film is manufactured by first forming the adhesive resin layer (A) on the surface of a separator (release film), and then bonding the adhesive resin layer (A) to another layer.

[0066] [Adhesive resin layer (B)] The adhesive film 50 of this embodiment includes an adhesive resin layer (B) on the second surface 10B side of the base layer 10 opposite the first surface 10A. The adhesive resin layer (B) is preferably a layer whose adhesive strength decreases in response to an external stimulus, so that the adhesive film 50 can be easily peeled off from the supporting substrate by applying an external stimulus. Here, examples of the adhesive resin layer (B) whose adhesive strength is reduced by an external stimulus include a heat-peeling type adhesive resin layer whose adhesive strength is reduced by heating, a light-peeling type adhesive resin layer whose adhesive strength is reduced by light such as radiation, etc. Here, examples of a method for applying the external stimulus include light irradiation and heat treatment. Examples of heat-peelable adhesive resin layers include adhesive resin layers made of a heat-expandable adhesive that contains an adhesive resin (B1) and further contains a gas-generating component, a heat-expandable adhesive that contains heat-expandable microspheres that expand to reduce adhesive strength, a heat-expandable adhesive whose adhesive strength is reduced by a crosslinking reaction of the adhesive component due to heat, etc. Among these, from the viewpoint of further suppressing the displacement of electronic components and further simplifying the manufacturing method, it is preferable that the adhesive film 50 of this embodiment contains a heat-expandable adhesive.

[0067] In the adhesive film 50 of this embodiment, the thermal expansion adhesive used in the adhesive resin layer (B) is an adhesive whose adhesive strength is reduced or lost by heating at a temperature preferably exceeding 150° C., more preferably exceeding 170° C. For example, a material can be selected that does not peel off at temperatures below 150° C. or below 170° C., but peels off at temperatures above 150° C. or above 170° C., and it is preferable that the adhesive film 50 has an adhesive strength sufficient to prevent it from peeling off from the supporting substrate during the manufacturing process of the electronic device. Here, the decrease or loss of adhesive strength due to heating at a temperature exceeding 150°C or 170°C can be evaluated by, for example, attaching the adhesive resin layer (B) side to a stainless steel plate, performing a heat treatment at 140°C for 1 hour, and then heating at a temperature exceeding 150°C or 170°C for 2 minutes, and then measuring the peel strength from the stainless steel plate. The specific heating temperature when heating at a temperature exceeding 150°C or 170°C is set to a temperature higher than the temperature at which gas is generated or the temperature at which the thermally expandable microspheres thermally expand, and is appropriately set depending on the type of gas generated or the type of thermally expandable microspheres. In this embodiment, the loss of adhesive strength refers to, for example, a case where the 180° peel strength measured under conditions of 23°C and a tensile speed of 300 mm / min is less than 0.5 N / 25 mm.

[0068] Examples of gas generating components that can be used in the thermal expansion type pressure sensitive adhesive include azo compounds, azide compounds, and Meldrum's acid derivatives. In addition, inorganic foaming agents such as ammonium carbonate, ammonium hydrogen carbonate, sodium hydrogen carbonate, ammonium nitrite, sodium boron hydroxide, and various azides, water, fluorinated alkane compounds such as trichloromonofluoromethane and dichloromonofluoromethane, azo compounds such as azobisisobutyronitrile, azodicarbonamide, and barium azodicarboxylate, paratoluenesulfonylhydrazide, diphenylsulfone-3,3'-disulfonylhydrazide, 4,4'-oxybis(benzenesulfonyl)hydrazide, and the like can be used. Also usable are organic foaming agents such as hydrazine compounds such as p-toluenesulfonylsemicarbazide and 4,4'-oxybis(benzenesulfonylsemicarbazide); triazole compounds such as 5-morpholyl-1,2,3,4-thiatriazole; and N-nitroso compounds such as N,N'-dinitrosopentamethylenetetramine and N,N'-dimethyl-N,N'-dinitrosoterephthalamide. The gas generating component may be added to the adhesive resin (B1) or may be directly bonded to the adhesive resin (B1).

[0069] As the heat-expandable microspheres used in the heat-expandable pressure-sensitive adhesive, for example, a microencapsulated foaming agent can be used. Examples of such heat-expandable microspheres include microspheres in which a substance that is easily gasified and expanded by heating, such as isobutane, propane, or pentane, is encapsulated in an elastic shell. Examples of materials constituting the shell include vinylidene chloride-acrylonitrile copolymer, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, polyacrylonitrile, polyvinylidene chloride, and polysulfone. Heat-expandable microspheres can be produced, for example, by a coacervation method or an interfacial polymerization method. Thermally expandable microspheres can be added to the adhesive resin.

[0070] The lower limit of the content of at least one selected from the gas-generating component and the heat-expandable microspheres can be appropriately set depending on the expansion ratio and decrease in adhesive strength of the heat-peelable adhesive resin layer (B) and is not particularly limited, but is preferably 1 part by mass or more, more preferably 10 parts by mass or more, and even more preferably 12 parts by mass or more, per 100 parts by mass of the adhesive resin (B1) in the heat-peelable adhesive resin layer (B). The upper limit of the content of at least one selected from the gas-generating component and the heat-expandable microspheres is preferably 150 parts by mass or less, more preferably 130 parts by mass or less, and even more preferably 100 parts by mass or less, per 100 parts by mass of the adhesive resin (B1) in the heat-peelable adhesive resin layer (B). It is preferable to design the temperature at which gas is generated or the temperature at which the heat-expandable microspheres expand is greater than 150°C or greater than 170°C.

[0071] Examples of the adhesive resin (B1) constituting the thermally expandable adhesive include (meth)acrylic resin (q), urethane resin, silicone resin, polyolefin resin, polyester resin, polyamide resin, fluorine resin, styrene-diene block copolymer resin, etc. Among these, (meth)acrylic resin (q) is preferred.

[0072] The (meth)acrylic resin (q) used in the adhesive resin layer (B) may be, for example, a copolymer containing a (meth)acrylic acid alkyl ester monomer unit (q1) and a monomer unit (q2) having a functional group capable of reacting with a crosslinking agent. In this embodiment, the (meth)acrylic acid alkyl ester means an acrylic acid alkyl ester, a methacrylic acid alkyl ester, or a mixture thereof.

[0073] The (meth)acrylic adhesive resin (q) of this embodiment can be obtained, for example, by copolymerizing a monomer mixture containing a (meth)acrylic acid alkyl ester monomer (q1) and a monomer (q2) having a functional group capable of reacting with a crosslinking agent.

[0074] The monomer (q1) forming the (meth)acrylic acid alkyl ester monomer unit (q1) includes a (meth)acrylic acid alkyl ester having an alkyl group having about 1 to 12 carbon atoms. A (meth)acrylic acid alkyl ester having an alkyl group having 1 to 8 carbon atoms is preferable. Specific examples include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, etc. These may be used alone or in combination of two or more. In the (meth)acrylic adhesive resin (q) of this embodiment, the lower limit of the content of the (meth)acrylic acid alkyl ester monomer unit (q1) is preferably 10 mass% or more, more preferably 50 mass% or more, and even more preferably 85 mass% or more, when the sum of all monomer units in the (meth)acrylic adhesive resin (q) is 100 mass%, from the viewpoint of further suppressing misalignment of electronic components in the sealing step. In the (meth)acrylic adhesive resin (q) of this embodiment, the upper limit of the content of the (meth)acrylic acid alkyl ester monomer unit (q1) is preferably 98.9 mass% or less, more preferably 97 mass% or less, and even more preferably 95 mass% or less, when the sum of all monomer units in the (meth)acrylic adhesive resin (q) is 100 mass%, from the viewpoint of further suppressing misalignment of electronic components in the sealing step.

[0075] Examples of the monomer (q2) that forms the monomer (q2) having a functional group that can react with a crosslinking agent include acrylic acid, methacrylic acid, itaconic acid, mesaconic acid, citraconic acid, fumaric acid, maleic acid, itaconic acid monoalkyl ester, mesaconic acid monoalkyl ester, citraconic acid monoalkyl ester, fumaric acid monoalkyl ester, maleic acid monoalkyl ester, acrylate, methacrylate, 2-hydroxyethyl acrylate, methacrylate, acrylamide, methacrylamide, tertiary butylaminoethyl acrylate, tertiary butylaminoethyl methacrylate, etc. Preferred are acrylic acid, methacrylic acid, acrylate, 2-hydroxyethyl acrylate, methacrylate, acrylamide, methacrylamide, etc. These may be used alone or in combination of two or more. In the (meth)acrylic adhesive resin (q) of this embodiment, the upper limit of the content of the monomer unit (q2) is preferably 40 mass% or less, more preferably 20 mass% or less, and even more preferably 10 mass% or less, when the sum of all monomer units in the (meth)acrylic adhesive resin (q) is taken as 100 mass%, from the viewpoint of further suppressing misalignment of electronic components in the sealing step. The lower limit is not particularly limited, but is, for example, 1 mass % or more.

[0076] The (meth)acrylic adhesive resin (q) of this embodiment may further contain, in addition to the monomer unit (q1) and the monomer unit (q2), a bifunctional monomer unit (q3) or a specific comonomer unit having surfactant properties (hereinafter referred to as a polymerizable surfactant). The polymerizable surfactant has the property of copolymerizing with the monomers (q1), (q2) and (q3), and also acts as an emulsifier in the case of emulsion polymerization.

[0077] Examples of the monomer (q3) forming the bifunctional monomer unit (q3) include allyl methacrylate, allyl acrylate, divinylbenzene, vinyl methacrylate, vinyl acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tetraethylene glycol di(meth)acrylate, and, for example, those having diacrylate or dimethacrylate at both ends and a main chain structure of propylene glycol type (e.g., manufactured by Nippon Oil & Fats Co., Ltd.; trade names: PDP-200, PDP-400, ADP-200, ADP-400), tetramethylene glycol type (e.g., manufactured by Nippon Oil & Fats Co., Ltd.; trade names: ADT-250, ADT-850), and mixtures thereof (e.g., manufactured by Nippon Oil & Fats Co., Ltd.; trade names: ADET-1800, ADPT-4000).

[0078] In the (meth)acrylic adhesive resin (q) of this embodiment, the upper limit of the content of the monomer unit (q3) is preferably 30 mass% or less, more preferably 20 mass% or less, even more preferably 15 mass% or less, and even more preferably 5 mass% or less, when the sum of all monomer units in the (meth)acrylic adhesive resin (q) is 100 mass%, from the viewpoint of further suppressing misalignment of electronic components in the sealing step. The lower limit is not particularly limited, but is, for example, 0.1 mass % or more.

[0079] Examples of polymerizable surfactants include those in which a polymerizable 1-propenyl group has been introduced into the benzene ring of polyoxyethylene nonylphenyl ether (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.; trade names: Aqualon RN-10, RN-20, RN-30, RN-50, etc.), those in which a polymerizable 1-propenyl group has been introduced into the benzene ring of an ammonium salt of a sulfate ester of polyoxyethylene nonylphenyl ether (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.; trade names: Aqualon HS-10, HS-20, HS-1025, etc.), and sulfosuccinic acid diesters having a polymerizable double bond in the molecule (manufactured by Kao Corporation; trade names: Latemul S-120A, S-180A, etc.). In the (meth)acrylic adhesive resin (q) of the present embodiment, the upper limit of the content of the polymerizable surfactant is preferably 30 mass % or less, more preferably 20 mass % or less, even more preferably 15 mass % or less, and even more preferably 5 mass % or less, when the sum of all monomer units in the (meth)acrylic adhesive resin (q) is taken as 100 mass %, from the viewpoint of further suppressing misalignment of electronic components in the sealing step. The lower limit is not particularly limited, but is, for example, 0.1 mass % or more.

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

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

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

[0083] The adhesive resin layer (B) of the present embodiment preferably further contains, in addition to the adhesive resin (B1), a crosslinking agent (B2) having two or more crosslinkable functional groups in one molecule. The crosslinking agent (B2) having two or more crosslinkable functional groups in one molecule is used to react with the functional groups of the adhesive resin (B1) to adjust the adhesive strength and cohesive strength. Examples of such crosslinking agents (B2) include epoxy compounds such as sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, glycerol polyglycidyl ether, neopentyl glycol diglycidyl ether, and resorcin diglycidyl ether; isocyanate compounds such as tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate triadduct of trimethylolpropane, polyisocyanate, diphenylmethane diisocyanate, and tolylene diisocyanate; and trimethylolpropane-tri-β-aziridinylpropionate. aziridine-based compounds such as N,N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxamide), N,N'-hexamethylene-1,6-bis(1-aziridinecarboxamide), N,N'-toluene-2,4-bis(1-aziridinecarboxamide), and trimethylolpropane-tri-β-(2-methylaziridine)propionate; tetrafunctional epoxy-based compounds such as N,N,N',N'-tetraglycidyl-m-xylylenediamine and 1,3-bis(N,N'-diglycidylaminomethyl)cyclohexane; and melamine-based compounds such as hexamethoxymethylolmelamine. These may be used alone or in combination of two or more. Among these, it is preferable to contain one or more compounds selected from the group consisting of epoxy compounds, isocyanate compounds, and aziridine compounds.

[0084] The content of the crosslinking agent (B2) is usually preferably within a range in which the number of functional groups in the crosslinking agent (B2) is not greater than the number of functional groups in the adhesive resin (B1). However, if necessary, an excess of the crosslinking agent (B2) may be contained when new functional groups are generated by the crosslinking reaction or when the crosslinking reaction is slow. The lower limit of the content of the crosslinking agent (B2) in the adhesive resin layer (B) is preferably 0.1 parts by mass or more, and more preferably 0.5 parts by mass or more, per 100 parts by mass of the adhesive resin (B1), from the viewpoint of further suppressing misalignment of electronic components during the sealing process. From the viewpoint of storage stability, the upper limit of the content of the crosslinking agent (B2) in the adhesive resin layer (B) is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, per 100 parts by mass of the adhesive resin (B1).

[0085] In the present embodiment, the adhesive resin layer (B) preferably contains a tackifier resin in addition to the adhesive resin (B1) from the viewpoint of improving adhesion to the support substrate. It is preferable to include a tackifier resin in the adhesive resin layer (B) because it is easy to adjust the adhesion to the support substrate at around room temperature. The tackifier resin is preferably one having a softening point of 100°C or higher. Specific examples of the tackifier resin include rosin-based resins such as rosin-based derivatives treated by esterification or the like; terpene-based resins such as α-pinene-based, β-pinene-based, dipentene-based, and terpene phenol-based resins; natural rosins such as gum-based, wood-based, and tall oil-based resins; petroleum resins obtained by hydrogenating, disproportionating, polymerizing, and maleating these natural rosins; and coumarone-indene resins.

[0086] Among these, those having a softening point in the range of 100 to 160° C. are more preferred, and those having a softening point in the range of 120 to 150° C. are particularly preferred. By using a tackifier resin having a softening point in the above range, not only is contamination and adhesive residue on the support substrate reduced, but the adhesion to the support substrate in the working environment can be further improved. Furthermore, by using a polymerized rosin ester-based tackifier resin as the tackifier resin, not only is contamination and adhesive residue on the support substrate reduced, but the adhesion to the support substrate in an environment of 80 to 130° C. is improved, and in the case of a heat-expandable pressure-sensitive adhesive containing heat-expandable microspheres, the heat-expandable microspheres can be more easily peeled off from the support substrate after expansion.

[0087] The blending ratio of the tackifier resin is not particularly limited, and may be appropriately selected so that the elastic modulus of the adhesive resin layer (B) can be adjusted to a desired predetermined numerical range. However, in terms of the elastic modulus and initial peeling force of the adhesive resin layer (B), it is preferable to set the blending ratio to 1 part by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the adhesive resin (B1). When the blending ratio of the tackifier resin is equal to or more than the lower limit value with respect to 100 parts by mass of the adhesive resin (B1), the adhesion to the support substrate during operation tends to be good. On the other hand, when the blending ratio is equal to or less than the upper limit value, the attachment to the support substrate at room temperature tends to be good. In terms of the adhesion to the support substrate and the attachment at room temperature, it is more preferable to set the blending ratio of the tackifier resin to 2 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the adhesive resin (B1). The acid value of the tackifier resin is preferably not more than 30. When the acid value of the tackifier resin is not more than the above upper limit, adhesive residue tends to be less likely to be left on the supporting substrate during peeling.

[0088] The adhesive resin layer (B) may contain additives such as plasticizers as other components. The lower limit of the total content of the adhesive resin (B1), the crosslinking agent (B2) and the tackifier resin in the adhesive resin layer (B) is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 90% by mass or more, and even more preferably 95% by mass or more, when the entire adhesive resin layer (B) is taken as 100% by mass. Furthermore, when the adhesive resin layer (B) is composed of a thermally expandable adhesive, the lower limit of the total content of the adhesive resin (B1), the crosslinking agent (B2), the tackifier resin, the gas-generating component and the thermally expandable microspheres in the adhesive resin layer (B) is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 90% by mass or more, and even more preferably 95% by mass or more, when the entire adhesive resin layer (B) is taken as 100% by mass. The upper limit is not particularly limited, but is, for example, 100% by mass or less.

[0089] The adhesive resin layer (B) may be a single layer or a multilayer. For example, by laminating two or more layers having different degrees of expansion by heating to form the adhesive resin layer (B), the adhesiveness and heat peelability can be changed between one side and the other side of the adhesive resin layer (B). The lower limit of the thickness of the adhesive resin layer (B) is preferably 3 μm or more, more preferably 20 μm or more, from the viewpoint of improving adhesiveness and thermal peelability. Moreover, from the viewpoint of improving the handleability of the adhesive film 50, the upper limit of the thickness of the adhesive resin layer (B) is preferably 300 μm or less, more preferably 150 μm or less.

[0090] The adhesive resin layer (B) can be formed, for example, by a method of applying an adhesive coating liquid onto the base layer 10, or by transferring the adhesive resin layer (B) formed on a separator onto the base layer 10. The adhesive coating liquid can be coated by a conventional coating method such as a roll coater method, a reverse roll coater method, a gravure roll method, a bar coat method, a comma coater method, a die coater method, etc. There is no particular restriction on the drying conditions of the coated adhesive, but it is generally preferable to dry the coated adhesive at a temperature range of 80 to 200°C for 10 seconds to 10 minutes. More preferably, the coated adhesive is dried at 80 to 170°C for 15 seconds to 5 minutes. In order to sufficiently promote the crosslinking reaction between the crosslinking agent and the adhesive, the coated adhesive may be heated at 40 to 80°C for about 5 to 300 hours after drying of the adhesive coating liquid is completed. The base material layer 10 and the adhesive resin layer (B) may be formed by co-extrusion molding, or the base material layer 10 in the form of a film and the adhesive resin layer (B) in the form of a film may be laminated together.

[0091] [Other layers] The adhesive film 50 of this embodiment may further include, for example, an unevenness-absorbing resin layer, an impact-absorbing layer, an easy-adhesion layer, etc., between the base layer 10 and the adhesive resin layer (A) or between the base layer 10 and the adhesive resin layer (B) as long as the effect of this embodiment is not impaired.

[0092] The electronic device manufacturing method of this embodiment can be preferably used to manufacture an electronic device 300 including a fan-out type package. That is, the electronic device 300 obtained by the electronic device manufacturing method of this embodiment includes a fan-out type package. In a fan-out type package, terminals can be spread out to the outside of the chip (fan out), so it can be used in applications where the number of terminals is large compared to the chip area. In addition, since a package substrate is not required, it can also be made thinner.

[0093] Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various configurations other than those described above can also be adopted.

[0094] The present invention is not limited to the above-described embodiment, and modifications and improvements within the scope of the present invention that can achieve the object of the present invention are included in the present invention. [Explanation of symbols]

[0095] A Adhesive resin layer B Adhesive resin layer 10 Base material layer 10A 1st side 10B 2nd side 50 Adhesive Film 60 Encapsulating material 70 Electronic Components 80 Support substrate 100 structures 200 Electronic equipment 300 Electronic equipment 310 wiring layer 320 Bump

Claims

1. an adhesive film including a base layer, an adhesive resin layer (A) provided on a first surface side of the base layer and for temporarily fixing an electronic component, and an adhesive resin layer (B) provided on a second surface side of the base layer; a plurality of electronic components attached to the adhesive resin layer (A) of the adhesive film; A step (a) of preparing a structure including a support substrate attached to the adhesive resin layer (B) of the adhesive film; (b) a step of sealing the electronic component with a sealing material; Including, The method for manufacturing an electronic device, wherein the step (b) includes a step of individually covering each of the plurality of electronic components with a sealing material.

2. 2. The method for manufacturing an electronic device according to claim 1, wherein step (b) comprises a step of individually covering each of the plurality of electronic components with the sealing material using one or more methods selected from the group consisting of a 3D printer method, a spray method, a screen printing method, and an inkjet method.

3. The method for manufacturing an electronic device according to claim 1 , wherein the sealing material includes an epoxy resin-based sealing material.

4. The method for manufacturing an electronic device according to claim 1 or 2, wherein the sealing temperature in the step (b) is 10° C. or higher and 45° C. or lower.

5. 3. The method for manufacturing an electronic device according to claim 1, further comprising, after the step (b), a step (c) of curing the sealing material by one or two methods selected from the group consisting of light irradiation and heat treatment.

6. 6. The method for manufacturing an electronic device according to claim 5, further comprising, after the step (c), a step (d) of applying an external stimulus to the adhesive resin layer (B) to reduce the adhesive strength of the adhesive resin layer (B) and peeling the support substrate from the structure.

7. The method for manufacturing an electronic device according to claim 6 , further comprising, after step (d), a step (e) of peeling the adhesive film from the plurality of electronic components.

8. The method for producing an electronic device according to claim 1 or 2, wherein the adhesive resin layer (A) contains an adhesive resin (A1).

9. The method for producing an electronic device according to claim 8, wherein the adhesive resin (A1) 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.

10. The method for producing an electronic device according to claim 8 , wherein the adhesive resin layer (A) further contains a crosslinking agent (A2) having two or more crosslinkable functional groups in one molecule.

11. The method for manufacturing an electronic device according to claim 10, wherein the content of the crosslinking agent (A2) is 0.1 parts by mass or more and 15 parts by mass or less per 100 parts by mass of the adhesive resin (A1).

12. The method for producing an electronic device according to claim 1 or 2, wherein the adhesive resin layer (B) contains a thermally expandable adhesive.

13. The method for manufacturing an electronic device according to claim 12 , wherein the thermally expandable adhesive is an adhesive whose adhesive strength is reduced or lost when heated at a temperature exceeding 150° C.

14. The method for manufacturing an electronic device according to claim 1 or 2, wherein the support substrate comprises at least one selected from the group consisting of a stainless steel substrate and a glass substrate.

15. The method for manufacturing an electronic device according to claim 1 or 2, wherein the step (a) includes a step (a-1) of attaching the adhesive film to the support substrate so that the adhesive resin layer (B) faces the support substrate.

16. The step (a) further includes a step (a-2) of obtaining the structure by arranging the plurality of electronic components on the adhesive resin layer (A) of the adhesive film attached to the support substrate. The method for producing an electronic device according to claim 15.

17. 3. The method for manufacturing an electronic device according to claim 1, wherein in the step (a), the distance between the plurality of electronic components is 10 [mu]m or more and 10 mm or less.

18. The method for manufacturing an electronic device according to claim 1 or 2, wherein the electronic device comprises a fan-out type package.

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