JP2024128730A - Adhesive film and method for producing adhesive film - Google Patents

Abstract

To provide an adhesive film which has an improved performance balance between unevenness followability and vacuum resistance.SOLUTION: An adhesive film used in a manufacturing step of an electronic device includes a base material layer 20, an uneven absorptive extrusion resin layer 30, and a thermosetting resin layer 40 containing a thermal radical polymerization initiator, wherein the uneven absorptive extrusion resin layer 30 and the thermosetting resin layer 40 are brought into direct contact with each other.SELECTED DRAWING: Figure 1

Description

The present invention relates to an adhesive film and a method for producing an adhesive film.

Some manufacturing methods for electronic devices include a process of forming a circuit of an electronic component, and then performing processes such as back grinding, ion implantation, laser annealing, sputtering, etc. on the surface of the electronic component opposite to the surface on which the circuit is formed. In these processes, an adhesive film is used to protect the surface on which the circuit is formed of the electronic component.
Examples of techniques relating to such adhesive films include those described in Patent Document 1 (WO 2015/152010).

Patent Document 1 describes a protective film that has a polyimide base material and a thermosetting adhesive layer provided on one surface of the polyimide base material and obtained from a composition containing an acrylic polymer (a), a thermal radical generator (b) having a 1-minute half-life temperature of 140° C. or more and 200° C. or less, and a crosslinking agent (c), and that is to be attached to a circuit-forming surface of a semiconductor wafer.
Patent Document 1 describes that when the protective film is applied to a manufacturing method for a semiconductor device including a step of attaching the protective film to the circuit-forming surface of a semiconductor wafer, thermally curing the thermosetting adhesive layer, and then performing vacuum heating while the protective film is still attached to the semiconductor wafer, it is possible to provide a protective film that protects the circuit-forming surface of the semiconductor wafer, suppresses the occurrence of lifting, and has excellent releasability when peeled off from the semiconductor wafer.

International Publication No. 2015/152010

In such a manufacturing method for electronic devices, if the adhesion between the electronic components and the adhesive film is insufficient, water or chemicals may penetrate between the electronic components and the adhesive film, causing deterioration of the electronic components.

The inventors' investigations have revealed that, in order to improve the adhesion between the electronic component and the adhesive film and to protect the electronic component, the adhesive film must be able to conform to the irregularities of the circuit-forming surface when attached to the circuit-forming surface of the electronic component (irregularity-following ability), and must be able to prevent the adhesive film attached to the electronic component from floating up even in a vacuum atmosphere (vacuum resistance).

Furthermore, according to the inventors' investigations, it has become clear that, although a method of making the adhesive film flexible can be used to improve its ability to conform to irregularities, the adhesive film is prone to deformation in a vacuum atmosphere and is prone to floating away from electronic components. On the other hand, a method of making the adhesive film hard can be used to improve its vacuum resistance, but it has become clear that this results in insufficient ability to conform to irregularities when attached to electronic components. In other words, it has become clear that there is a trade-off between the adhesive film's ability to conform to irregularities and its vacuum resistance.

The present invention was made in consideration of the above circumstances, and provides an adhesive film with an improved balance of unevenness-following ability and vacuum resistance.

According to the present invention, the following adhesive film and method for producing the adhesive film are provided.

式（Ｉ）中、波線は結合点を示す。

式（ＩＩ）中、波線は結合点を示す。
［５］
前記熱ラジカル重合開始剤の１分間半減期温度は、１４０℃以上２００℃以下である、前記［１］～［４］のいずれかに記載の粘着性フィルム。
［６］
前記熱ラジカル重合開始剤の水素引き抜き能が２０％以上である、前記［１］～［５］のいずれかに記載の粘着性フィルム。
［７］
前記熱硬化性樹脂層は、熱硬化性粘着層である、前記［１］～［６］のいずれかに記載の粘着性フィルム。
［８］
前記熱硬化性樹脂層を構成する樹脂が、（メタ）アクリル系樹脂を含む、前記［１］～［７］のいずれかに記載の粘着性フィルム。
［９］
前記凹凸吸収性押出樹脂層を構成する樹脂が、エチレン・酢酸ビニル共重合体、（メタ）アクリル系樹脂、エチレン・α－オレフィン共重合体、および低密度ポリエチレンからなる群から選択される少なくとも一種を含む、前記［１］～［８］のいずれかに記載の粘着性フィルム。
［１０］
前記凹凸吸収性押出樹脂層の厚みが２０μｍ以上５００μｍ以下である、前記［１］～［９］のいずれかに記載の粘着性フィルム。
［１１］
前記基材層を構成する樹脂が、ポリエチレンナフタレート、ポリエチレンテレフタレート、およびポリイミドからなる群から選択される少なくとも一種を含む、前記［１］～［１０］のいずれかに記載の粘着性フィルム。
［１２］
前記電子装置の製造工程は、回路形成面を有する電子部品と、前記電子部品の前記回路形成面側に貼り合わされた前記粘着性フィルムと、を備える構造体を準備する工程（Ａ）と、真空雰囲気下で、前記電子部品の前記回路形成面側とは反対側の面を処理する工程（Ｂ）と、を含む、前記［１］～［１１］のいずれかに記載の粘着性フィルム。
［１３］
前記電子装置がパワー半導体装置である、前記［１］～［１２］のいずれかに記載の粘着性フィルム。
［１４］
前記［１］～［１３］のいずれかに記載の粘着性フィルムを製造するための製造方法であって、
前記基材層上に前記凹凸吸収性押出樹脂層を押出成形する工程と、
前記凹凸吸収性押出樹脂層上に、熱ラジカル重合開始剤を含む熱硬化性樹脂組成物を用いて前記熱硬化性樹脂層を形成する工程と、
を備える、粘着性フィルムの製造方法。 [1]
An adhesive film for use in a manufacturing process of an electronic device, comprising:
The film comprises a base layer, a roughness-absorbing extruded resin layer, and a thermosetting resin layer containing a thermal radical polymerization initiator,
The unevenness-absorbing extruded resin layer and the thermosetting resin layer are in direct contact with each other.
[2]
The adhesive film described in [1], wherein the content of the thermal radical polymerization initiator in the resin composition for forming the unevenness-absorbing extruded resin layer is less than 0.3 parts by mass when the total amount of the resin composition for forming the unevenness-absorbing extruded resin layer is 100 parts by mass.
[3]
The pressure-sensitive adhesive film according to [1] or [2], wherein the thermal radical polymerization initiator contains a peroxide.
[4]
The pressure-sensitive adhesive film according to [3] above, wherein the peroxide contains at least one structure selected from the group consisting of the following formula (I) and the following formula (II) in its molecule.

In formula (I), the wavy lines indicate points of attachment.

In formula (II), the wavy line indicates the point of attachment.
[5]
The pressure-sensitive adhesive film according to any one of the above [1] to [4], wherein the one-minute half-life temperature of the thermal radical polymerization initiator is 140° C. or higher and 200° C. or lower.
[6]
The pressure-sensitive adhesive film according to any one of the above [1] to [5], wherein the thermal radical polymerization initiator has a hydrogen abstraction ability of 20% or more.
[7]
The pressure-sensitive adhesive film according to any one of the above [1] to [6], wherein the thermosetting resin layer is a thermosetting pressure-sensitive adhesive layer.
[8]
The pressure-sensitive adhesive film according to any one of [1] to [7], wherein the resin constituting the thermosetting resin layer includes a (meth)acrylic resin.
[9]
The adhesive film according to any one of [1] to [8], wherein the resin constituting the irregularity-absorbing extruded resin layer comprises at least one selected from the group consisting of ethylene-vinyl acetate copolymer, (meth)acrylic resin, ethylene-α-olefin copolymer, and low-density polyethylene.
[10]
The pressure-sensitive adhesive film according to any one of [1] to [9], wherein the thickness of the irregularity-absorbing extruded resin layer is 20 μm or more and 500 μm or less.
[11]
The adhesive film according to any one of [1] to [10], wherein the resin constituting the base layer comprises at least one selected from the group consisting of polyethylene naphthalate, polyethylene terephthalate, and polyimide.
[12]
The manufacturing process of the electronic device includes a step (A) of preparing a structure including an electronic component having a circuit formation surface and the adhesive film attached to the circuit formation surface side of the electronic component, and a step (B) of treating the surface of the electronic component opposite the circuit formation surface side under a vacuum atmosphere. The adhesive film according to any one of the above [1] to [11].
[13]
The pressure-sensitive adhesive film according to any one of [1] to [12], wherein the electronic device is a power semiconductor device.
[14]
A manufacturing method for manufacturing the adhesive film according to any one of [1] to [13],
A step of extruding the irregularity-absorbing extruded resin layer onto the base material layer;
forming the thermosetting resin layer on the irregularity-absorbing extruded resin layer using a thermosetting resin composition containing a thermal radical polymerization initiator;
The method for producing an adhesive film comprises:

The present invention provides an adhesive film with an improved balance of conformability and vacuum resistance.

1 is a cross-sectional view showing a schematic diagram of a preferred layer structure of an adhesive film according to an embodiment of the present invention. 1 is a cross-sectional view showing a structure in step (A) of a method for manufacturing an electronic device according to an embodiment of the present invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In all drawings, similar components are given the same reference numerals and the description will be omitted as appropriate. The drawings are schematic and do not correspond to the actual dimensional ratios. Furthermore, unless otherwise specified, the numerical range "A to B" represents A or more and B or less. Furthermore, in this embodiment, "(meth)acrylic" means acrylic, methacrylic, or both acrylic and methacrylic.

<Adhesive film>
FIG. 1 is a cross-sectional view showing a schematic diagram of a preferred layer structure of an adhesive film according to an embodiment of the present invention.
The adhesive film of this embodiment is an adhesive film 50 used in the manufacturing process of electronic devices, and comprises a base layer 20, an unevenness-absorbing extruded resin layer 30, and a thermosetting resin layer 40 containing a thermal radical polymerization initiator, and the unevenness-absorbing extruded resin layer 30 and the thermosetting resin layer 40 are in direct contact with each other.

The layer structure of the adhesive film 50 of this embodiment is not particularly limited as long as it comprises a base layer 20, an unevenness-absorbing extruded resin layer 30, and a thermosetting resin layer 40, and the unevenness-absorbing extruded resin layer 30 and the thermosetting resin layer 40 are in direct contact with each other.
The layer structure of the adhesive film 50 of this embodiment may be, for example, a structure including a base layer 20, an unevenness-absorbing extruded resin layer 30, and a thermosetting resin layer 40, in this order, with each layer being in direct contact with the other (the layer structure of Figure 1); a structure including a base layer 20, a thermosetting resin layer 40, an unevenness-absorbing extruded resin layer 30, and an adhesive layer, in this order, with each layer being in direct contact with the other; etc.
The layer structure of the adhesive film 50 of this embodiment preferably comprises a base layer 20, an irregularity-absorbing extruded resin layer 30, and a thermosetting resin layer 40 in this order, with each layer being in direct contact with the others.

The overall thickness of the adhesive film of this embodiment is preferably 10 μm or more, more preferably 20 μm or more, even more preferably 40 μm or more, even more preferably 60 μm or more, even more preferably 80 μm or more, even more preferably 100 μm or more, even more preferably 120 μm or more, from the viewpoint of further improving the handleability of the adhesive film, and is preferably 700 μm or less, more preferably 500 μm or less, even more preferably 300 μm or less, even more preferably 250 μm or less, even more preferably 200 μm or less, from the viewpoint of further improving the unevenness-following ability of the adhesive film.

Below, we will explain each layer that makes up the adhesive film 50 of this embodiment.

[Base layer]
The base layer 20 is a layer provided for the purpose of improving the balance of performance such as handleability, mechanical properties, and heat resistance of the pressure-sensitive adhesive film 50 .
The base layer 20 is not particularly limited, but may be, for example, a resin film.
The resin constituting the base layer 20 preferably contains at least one selected from the group consisting of polyethylene naphthalate, polyethylene terephthalate, and polyimide, and from the viewpoint of further improving vacuum resistance, it is more preferable that the resin contains polyethylene naphthalate.

The substrate layer 20 may be a single layer or two or more layers.
The resin film used to form the base layer 20 may be in the form of an unstretched film, or a uniaxially or biaxially stretched film.

The thickness of the base layer 20 is preferably 10 μm or more, more preferably 20 μm or more, even more preferably 30 μm or more, and even more preferably 40 μm or more, from the viewpoint of further improving the handleability of the adhesive film 50, and is preferably 500 μm or less, more preferably 300 μm or less, even more preferably 200 μm or less, even more preferably 100 μm or less, even more preferably 80 μm or less, and even more preferably 60 μm or less, from the viewpoint of further improving the unevenness-following ability of the adhesive film 50.

The substrate layer 20 may be subjected to a surface treatment to further improve adhesion to other layers. Specifically, corona treatment, plasma treatment, undercoat treatment, primer coat treatment, etc. may be performed.

[Irregularity-absorbing extruded resin layer]
The irregularity-absorbing extruded resin layer 30 is a layer provided to further improve the balance of the performance of the adhesive film 50 between its irregularity-following ability and vacuum resistance.
The irregularity-absorbing extruded resin layer 30 is not particularly limited as long as it is a layer formed by extrusion of resin.

The resin constituting the irregularity-absorbing extruded resin layer 30 preferably contains at least one selected from the group consisting of ethylene-vinyl acetate copolymer, (meth)acrylic resin, ethylene-α-olefin copolymer, and low-density polyethylene, more preferably contains one or two selected from the group consisting of ethylene-vinyl acetate copolymer and (meth)acrylic resin, and even more preferably contains ethylene-vinyl acetate copolymer.

The ethylene-vinyl acetate copolymer of the present embodiment is a copolymer of ethylene and vinyl acetate, for example, a random copolymer.
The content of structural units derived from vinyl acetate in the ethylene-vinyl acetate copolymer is preferably 5 mass% or more, more preferably 10 mass% or more, and even more preferably 15 mass% or more, from the viewpoint of further improving the performance balance between the unevenness-following ability and vacuum resistance of the adhesive film 50, and is preferably 50 mass% or less, more preferably 45 mass% or less, even more preferably 40 mass% or less, even more preferably 35 mass% or less, even more preferably 30 mass% or less, and even more preferably 25 mass% or less, from the viewpoint of further improving the performance balance between the unevenness-following ability and vacuum resistance of the adhesive film 50.
The vinyl acetate content can be measured in accordance with JIS K7192:1999.

The ethylene-vinyl acetate copolymer is preferably a binary copolymer consisting of only ethylene and vinyl acetate, but may contain at least one copolymer component selected from the following in addition to ethylene and vinyl acetate: vinyl ester monomers such as vinyl formate, vinyl glycolate, vinyl propionate, and vinyl benzoate; acrylic monomers such as acrylic acid, methacrylic acid, ethacrylic acid, or salts or alkyl esters of these; and the like. When copolymer components other than ethylene and vinyl acetate are contained, it is preferable that the amount of the copolymer components other than ethylene and vinyl acetate in the ethylene-vinyl acetate copolymer is 0.5% by mass or more and 5% by mass or less.

The melt flow rate (MFR) of the ethylene-vinyl acetate copolymer, measured in accordance with JIS K7210:1999 under conditions of 190°C and a load of 2.16 kg, is preferably 0.1 g/10 min or more, more preferably 0.5 g/10 min or more, even more preferably 1.0 g/10 min or more, even more preferably 1.5 g/10 min or more, and even more preferably 2.0 g/10 min or more, from the viewpoint of further improving the moldability of the irregularity-absorbing extruded resin layer 30, and is preferably 50 g/10 min or less, more preferably 40 g/10 min or less, even more preferably 20 g/10 min or less, even more preferably 10 g/10 min or less, even more preferably 5.0 g/10 min or less, and even more preferably 3.0 g/10 min or less, from the viewpoint of further improving the storage stability of the adhesive film 50.

The ethylene/α-olefin copolymer of the present embodiment is, for example, a copolymer obtained by copolymerizing ethylene with an α-olefin having 3 to 20 carbon atoms.
As the α-olefin, for example, α-olefins having 3 to 20 carbon atoms can be used alone or in combination of two or more. Preferably, the α-olefin has 3 to 10 carbon atoms, and more preferably, the α-olefin has 3 to 8 carbon atoms. Specific examples of the α-olefin include propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 3,3-dimethyl-1-butene, 4-methyl-1-pentene, 1-octene, 1-decene, and 1-dodecene. Among them, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, and 1-octene are preferred from the viewpoint of availability. The ethylene-α-olefin copolymer may be a random copolymer or a block copolymer, but a random copolymer is preferred from the viewpoint of flexibility.

The melting point of the resin constituting the unevenness-absorbing extruded resin layer 30 is preferably 40°C or higher, more preferably 50°C or higher, even more preferably 60°C or higher, even more preferably 70°C or higher, and even more preferably 80°C or higher, from the viewpoint of further improving the storage stability of the adhesive film 50, and is preferably 100°C or lower, more preferably 95°C or lower, more preferably 90°C or lower, and even more preferably 85°C or lower, from the viewpoint of further improving the unevenness-following ability of the adhesive film 50.
When the irregularity-absorbing extruded resin layer 30 is made of two or more types of resin, the melting point of the resin that makes up the irregularity-absorbing extruded resin layer 30 is the peak temperature of the maximum melting peak measured by DSC.

The irregularity-absorbing extruded resin layer 30 can be obtained by extruding a resin. Specifically, the irregularity-absorbing extruded resin layer 30 can be obtained, for example, by dry-blending or melt-kneading a resin and an additive to obtain a resin composition, and then extruding the resin composition. The additives may be added as necessary. Specific examples of additives include crosslinking agents and antioxidants.

The content of the thermal radical polymerization initiator in the resin composition for forming the unevenness-absorbing extruded resin layer 30 is preferably less than 0.3 parts by mass, more preferably less than 0.1 parts by mass, even more preferably less than 0.01 parts by mass, and even more preferably 0.00 parts by mass, when the entire resin composition for forming the unevenness-absorbing extruded resin layer 30 is taken as 100 parts by mass.
When the content of the thermal radical polymerization initiator contained in the resin composition for forming the unevenness-absorbing extruded resin layer 30 is less than the above upper limit value, the moldability can be further improved when extrusion molding the unevenness-absorbing extruded resin layer 30, and the unevenness-following ability of the adhesive film 50 can be further improved.
Here, the content of the thermal radical polymerization initiator contained in the resin composition for forming the above-mentioned unevenness-absorbing extruded resin layer 30 is, in other words, the amount of thermal radical polymerization initiator charged when forming the unevenness-absorbing extruded resin layer 30.
The thermal radical polymerization initiator means the same as the thermal radical polymerization initiator contained in the thermosetting resin layer described below.

The thickness of the irregularity-absorbing extruded resin layer 30 is preferably 20 μm or more, more preferably 40 μm or more, and even more preferably 60 μm or more, from the viewpoint of further improving the handleability of the adhesive film 50, and is preferably 500 μm or less, more preferably 300 μm or less, even more preferably 200 μm or less, and even more preferably 150 μm or less, from the viewpoint of further improving the performance balance between the irregularity-following ability and vacuum resistance of the adhesive film 50.

[Thermosetting resin layer]
The thermosetting resin layer 40 contains a thermal radical polymerization initiator, and is a layer that is in direct contact with the irregularity-absorbing extruded resin layer 30 .

When the unevenness-absorbing extruded resin layer 30 and the thermosetting resin layer 40 containing a thermal radical polymerization initiator are in direct contact with each other, the vacuum resistance of the adhesive film 50 is further improved. Although the exact mechanism is unclear, the inventors believe that when the temperature of the adhesive film 50 attached to the electronic component becomes high (e.g., 150°C or higher) during the manufacturing process of the electronic device, the thermal radical polymerization initiator contained in the thermosetting resin layer 40 diffuses into the unevenness-absorbing extruded resin layer 30, hardening the resin that constitutes the unevenness-absorbing extruded resin layer 30, hardening the entire adhesive film 50, and making it difficult for the adhesive film 50 attached to the electronic component to float.

The thermosetting resin layer 40 is preferably a thermosetting adhesive layer. In this specification, the thermosetting adhesive layer means a layer that is provided to bond the adhesive film 50 to the circuit formation surface of the electronic component.

The thermosetting resin layer 40 contains a resin and a thermal radical polymerization initiator.
The resin constituting the thermosetting resin layer 40 is not particularly limited, but may include, for example, a (meth)acrylic resin, a silicone resin, a urethane resin, an olefin resin, and a styrene resin, and among these, a (meth)acrylic resin is preferable.
When the thermosetting resin layer 40 is a thermosetting adhesive layer, it is preferable that the resin constituting the thermosetting resin layer 40 contains a (meth)acrylic resin, since this makes it easier to adjust the adhesive strength.

Examples of the (meth)acrylic resin of the present embodiment include homopolymers of (meth)acrylic acid ester compounds, copolymers of (meth)acrylic acid ester compounds and comonomers, etc. Examples of the (meth)acrylic acid ester compounds include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, glycidyl (meth)acrylate, etc. These (meth)acrylic acid ester compounds may be used alone or in combination of two or more.
Examples of comonomers constituting the (meth)acrylic copolymer include vinyl acetate, (meth)acrylonitrile, styrene, (meth)acrylic acid, itaconic acid, (meth)acrylamide, methylol (meth)acrylamide, maleic anhydride, etc. These comonomers may be used alone or in combination of two or more.

The thermal radical polymerization initiator of the present embodiment is, for example, at least one selected from the group consisting of peroxides and azo compounds, and is preferably a peroxide.
The peroxide of the present embodiment is preferably 1,1-di(t-butylperoxy)-2-methylcyclohexane, 1,1-di(t-butylperoxy)-cyclohexane, 2,2-di(4,4-di-(t-butylperoxy)cyclohexyl)propane, t-butylperoxymaleic acid, t-butylperoxy-3,3,5-trimethylhexanoate, t-butylperoxylaurate, t-butylperoxyisopropyl monocarbonate, t-butylperoxy-2-ethylhexyl monocarbonate, or t-hexylperoxybenzone. The at least one selected from the group consisting of butyl peroxyacetate, t-butylperoxyacetate, 2,2-di(t-butylperoxy)butane, t-butylperoxybenzoate, n-butyl-4,4-di-(t-butylperoxy)valerate, di(2-t-butylperoxyisopropyl)benzene, dicumyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, t-butylcumyl peroxide, di-t-butyl peroxide, and 2,5-dimethyl-2,5-di(t-butylperoxy)-3-hexyne.

The peroxide of this embodiment preferably contains at least one structure selected from the group consisting of the following formula (I) and the following formula (II) in the molecule, and more preferably contains the following formula (II) in the molecule.

In formula (I), the wavy lines indicate the attachment points.

In formula (II), the wavy lines indicate the bond points.

The one-minute half-life temperature of the thermal radical polymerization initiator of this embodiment is preferably 140°C or higher, more preferably 145°C or higher, even more preferably 150°C or higher, and preferably 200°C or lower, more preferably 195°C or lower, even more preferably 190°C or lower, even more preferably 185°C or lower, even more preferably 180°C or lower. When the one-minute half-life temperature of the thermal radical polymerization initiator is equal to or higher than the lower limit, the thermal radical polymerization initiator is less likely to thermally decompose when forming the thermosetting resin layer 40 in the manufacturing process of the adhesive film 50, and the unevenness-following ability of the adhesive film 50 is further improved, which is preferable. When the one-minute half-life temperature of the thermal radical polymerization initiator is equal to or lower than the upper limit, the thermal radical polymerization initiator decomposes at a temperature lower than the temperature at which the resin contained in the adhesive film 50 is excessively softened, and the vacuum resistance of the adhesive film 50 is further improved, which is preferable.

The hydrogen abstraction ability of the thermal radical polymerization initiator of this embodiment is preferably 20% or more, more preferably 25% or more, and even more preferably 30% or more, and the upper limit is not particularly limited, but may be 90% or less, or 80% or less. When the hydrogen abstraction ability of the thermal radical polymerization initiator of this embodiment is equal to or more than the above lower limit, the resin contained in the pressure-sensitive adhesive film 50 is more easily crosslinked, and the vacuum resistance of the pressure-sensitive adhesive film 50 is further improved, which is preferable.
Here, the hydrogen abstraction ability means a value calculated by a radical trapping method using α-methylstyrene dimer as a radical trapping agent.
More specifically, first, a thermal radical polymerization initiator is decomposed in the coexistence of α-methylstyrene dimer and cyclohexane. Among the radicals generated from the thermal radical polymerization initiator, radicals with weak hydrogen abstraction ability are captured by α-methylstyrene dimer. On the other hand, radicals with strong hydrogen abstraction ability abstract hydrogen from cyclohexane, generating a cyclohexyl radical. The cyclohexyl radical is captured by α-methylstyrene dimer and is led to a trapping product of the cyclohexyl radical. The hydrogen abstraction ability is the ratio (molar fraction) of the amount of the trapping product of the cyclohexyl radical to the theoretical amount of radicals generated.

The content of the thermal radical polymerization initiator contained in the thermosetting resin layer 40, when the content of the (meth)acrylic resin contained in the thermosetting resin layer 40 is taken as 100 parts by mass, is preferably 0.1 parts by mass or more, more preferably 0.3 parts by mass or more, and even more preferably 0.5 parts by mass or more, from the viewpoint of further improving the vacuum resistance of the adhesive film 50, and is preferably 2.0 parts by mass or less, more preferably 1.8 parts by mass or less, and even more preferably 1.5 parts by mass or less, from the viewpoint of further improving the unevenness-following ability of the adhesive film 50.
Here, the content of the thermal radical polymerization initiator contained in the thermosetting resin layer 40 means the content of the thermal radical polymerization initiator in the thermosetting resin composition for forming the thermosetting resin layer 40. That is, the content of the thermal radical polymerization initiator in this specification means the amount charged when forming the thermosetting resin layer 40. The contents of the crosslinking agent and the polyfunctional acrylate described below also mean the amount charged, like the thermal radical polymerization initiator.

The thermosetting resin layer 40 may contain a crosslinking agent.
Examples of the crosslinking agent of the present embodiment include epoxy compounds such as sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, and diglycerol polyglycidyl ether; aziridine compounds such as tetramethylolmethane-tri-β-aziridinyl propionate, trimethylolpropane-tri-β-aziridinyl propionate, N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxamide), and N,N'-hexamethylene-1,6-bis(1-aziridinecarboxamide); and isocyanate compounds such as tetramethylene diisocyanate, hexamethylene diisocyanate, and polyisocyanate.

The content of the crosslinking agent contained in the thermosetting resin layer 40 is preferably 0.1 parts by mass or more, more preferably 0.3 parts by mass or more, even more preferably 0.5 parts by mass or more, even more preferably 1.0 parts by mass or more, even more preferably 1.5 parts by mass or more, even more preferably 2.0 parts by mass or more, and even more preferably 2.3 parts by mass or more, from the viewpoint of further improving the performance balance of the unevenness-following ability and vacuum resistance of the adhesive film 50, when the content of the (meth)acrylic resin contained in the thermosetting resin layer 40 is taken as 100 parts by mass. And, from the viewpoint of further improving the performance balance of the unevenness-following ability and vacuum resistance of the adhesive film 50, it is preferably 10.0 parts by mass or less, more preferably 7.0 parts by mass or less, even more preferably 5.0 parts by mass or less, even more preferably 4.0 parts by mass or less, and even more preferably 3.0 parts by mass or less.

The thermosetting resin layer 40 may further contain a polyfunctional acrylate in addition to the (meth)acrylic resin. The polyfunctional acrylate in this embodiment is an acrylate having two or more radically reactive double bonds.
Examples of the polyfunctional acrylate of the present embodiment include urethane acrylate, epoxy acrylate, polyester acrylate, polyether acrylate, pentaerythritol polyacrylate, dipentaerythritol polyacrylate, ethoxylated isocyanuric acid triacrylate, trimethylolpropane triacrylate, and ditrimethylolpropane tetraacrylate.

When the content of the (meth)acrylic resin contained in the thermosetting resin layer 40 is taken as 100 parts by mass, the content of the polyfunctional acrylate contained in the thermosetting resin layer 40 is preferably 2.0 parts by mass or more, more preferably 3.0 parts by mass or more, and even more preferably 4.0 parts by mass or more, from the viewpoint of further improving the performance balance of the unevenness-following ability and vacuum resistance of the adhesive film 50, and is preferably 20.0 parts by mass or less, more preferably 15.0 parts by mass or less, and even more preferably 12.0 parts by mass or less, from the viewpoint of further improving the performance balance of the unevenness-following ability and vacuum resistance of the adhesive film 50.

The thickness of the thermosetting resin layer 40 is not particularly limited, but is preferably 1 μm or more, more preferably 5 μm or more, even more preferably 10 μm or more, even more preferably 15 μm or more, and is preferably 100 μm or less, more preferably 50 μm or less, even more preferably 30 μm or less, even more preferably 25 μm or less.

The thermosetting resin layer 40 can be formed, for example, by applying a thermosetting resin composition onto the irregularity-absorbing extruded resin layer 30 .
The method for applying the thermosetting resin composition may be a conventionally known application 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 are no particular limitations on the drying conditions for the applied thermosetting resin composition, but it is generally preferable to dry the composition at a temperature range of 80 to 200° C. for 10 seconds to 10 minutes. More preferably, the composition is dried at 80 to 170° C. for 15 seconds to 5 minutes.

[Other layers]
The adhesive film 50 comprises a base layer 20, an unevenness-absorbing extruded resin layer 30, and a thermosetting resin layer 40, and may comprise other layers as long as the unevenness-absorbing extruded resin layer 30 and the thermosetting resin layer 40 are in direct contact with each other.
As the other layer, for example, when the thermosetting resin layer 40 is not a thermosetting adhesive layer, an adhesive layer for attaching the adhesive film 50 to the circuit formation surface of the electronic component may be provided.
An adhesive layer may be provided between each layer of the adhesive film 50. The adhesive layer can improve the adhesion between each layer.
The adhesive film 50 may further include a separator.

<Method for producing adhesive film>
A preferred method for producing the adhesive film 50 of this embodiment will be described.
The manufacturing method of the adhesive film of this embodiment includes a step of extruding an unevenness-absorbing extruded resin layer 30 onto a base material layer 20, and a step of forming a thermosetting resin layer 40 on the unevenness-absorbing extruded resin layer 30 using a thermosetting resin composition containing a thermal radical polymerization initiator.

The process of forming the thermosetting resin layer 40 on the unevenness-absorbing extruded resin layer 30 using a thermosetting resin composition containing a thermal radical polymerization initiator preferably includes a process of applying the thermosetting resin composition containing the thermal radical polymerization initiator onto the unevenness-absorbing extruded resin layer 30, and a process of drying the thermosetting resin composition to form the thermosetting resin layer 40.
In the step of drying the thermosetting resin composition to form the thermosetting resin layer 40, the drying temperature is preferably 80° C. or more and 200° C. or less, and more preferably 80° C. or more and 170° C. or less.
In the step of drying the thermosetting resin composition to form the thermosetting resin layer 40, the drying time is preferably from 10 seconds to 10 minutes, and more preferably from 15 seconds to 5 minutes.

Next, a method for manufacturing the electronic device of this embodiment will be described.
The electronic device in this embodiment includes elements, devices, final products, etc. to which electronic engineering technology is applied, such as semiconductor devices, power semiconductor devices, semiconductor chips, semiconductor elements, printed wiring boards, electric circuit display devices, information and communication terminals, light-emitting diodes, physical batteries, and chemical batteries.
The electronic device of this embodiment is preferably a power semiconductor device. A power semiconductor device is a semiconductor device that controls and converts electric power, and generally has a rated current of 1 A or more.

The manufacturing method of the electronic device of the present embodiment is not particularly limited, but preferably includes the steps of: (A) preparing a structure including an electronic component having a circuit formation surface and the adhesive film attached to the circuit formation surface side of the electronic component; and (B) treating the surface of the electronic component opposite the circuit formation surface side under a vacuum atmosphere.
Each step of the method for manufacturing an electronic device will now be described.

[Step (A)]
FIG. 2 is a cross-sectional view that illustrates the structure 100 in the step (A).
In step (A), a structure 100 is prepared that includes an electronic component 10 having a circuit-formation surface 10A and an adhesive film 50 attached to the circuit-formation surface 10A side of the electronic component 10.

Such a structure 100 can be produced by attaching an adhesive film 50 to the circuit formation surface 10A of the electronic component 10.
The method of bonding the adhesive film 50 to the circuit-forming surface 10A of the electronic component 10 is not particularly limited, and the bonding can be performed by a known method. For example, the bonding may be performed manually or by a device called an automatic bonding machine to which a roll-shaped adhesive film 50 is attached.

When bonding the circuit formation surface 10A of the electronic device 10, for example, the adhesive film 50 is heated. The heating temperature is set appropriately depending on the type of adhesive film 50, so it is not particularly limited, but may be, for example, 40°C or higher, 45°C or higher, and 120°C or lower, or 110°C or lower.

The electronic component 10 is not particularly limited as long as it has a circuit formation surface 10A, but examples thereof include a semiconductor wafer, a sapphire substrate, a lithium tantalate substrate, a molded wafer, a molded panel, a molded array package, a semiconductor substrate, etc., and a semiconductor wafer is preferred.
Examples of semiconductor wafers include silicon wafers, sapphire wafers, germanium wafers, germanium-arsenic wafers, gallium-phosphorus wafers, gallium-arsenic-aluminum wafers, gallium-arsenic wafers, and lithium tantalate wafers, with silicon wafers being preferred.

Circuits such as wiring, capacitors, diodes, transistors, etc. are formed on the surface of the circuit-forming surface 10A of the electronic component 10. The circuit-forming surface may be subjected to plasma treatment.
Furthermore, the circuit formation surface 10A of the electronic component 10 may be an uneven surface due to the presence of bump electrodes or the like.
Furthermore, the bump electrodes are joined to electrodes formed on the mounting surface, for example, when mounting an electronic device 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, etc.).
Examples of the bump electrode include a ball bump, a printed bump, a stud bump, a plated bump, and a pillar bump. That is, the bump electrode is usually a convex electrode. These bump electrodes may be used alone or in combination of two or more kinds.
The height and diameter of the bump electrodes are not particularly limited, but are preferably 10 μm or more, more preferably 50 μm or more, and preferably 400 μm or less, more preferably 300 μm or less. The bump pitch is also not particularly limited, but is preferably 20 μm or more, more preferably 100 μm or more, and preferably 600 μm or less, more preferably 500 μm or less.
The metal species constituting the bump electrode is not particularly limited, and examples thereof include solder, silver, gold, copper, tin, lead, bismuth, and alloys thereof, but the adhesive film 50 is preferably used when the bump electrode is a solder bump. These metal species may be used alone or in combination of two or more.

[Step (B)]
In the step (B), surface 10B of electronic component 10 opposite circuit-forming surface 10A is treated in a vacuum atmosphere.
Step (B) is a step subsequent to step (A). Therefore, in step (B), surface 10B of electronic component 10 in structure 100 opposite to circuit formation surface 10A is treated.

In step (B), a vacuum atmosphere means a low-pressure state in which the pressure is reduced below atmospheric pressure by a vacuum device, and may be, for example, 1000 Pa or less, 100 Pa or less, or 10 Pa or less.

Step (B) may be performed under high temperature conditions. When step (B) is performed under high temperature conditions, the temperature of the structure 100 in step (B) is preferably 60°C or higher, more preferably 80°C or higher, even more preferably 100°C or higher, even more preferably 120°C or higher, even more preferably 140°C or higher, and preferably 230°C or lower, more preferably 210°C or lower, even more preferably 190°C or lower, even more preferably 170°C or lower.

In step (B), the method for treating surface 10B of electronic component 10 opposite circuit-forming surface 10A is not particularly limited, and may be a step in a known method for manufacturing electronic devices.
The step (B) is preferably at least one step selected from the group consisting of an ion implantation step, a metal film formation step, and an annealing treatment step.

The method for manufacturing an electronic device according to the present embodiment preferably further includes a step of heating the structure 100 prior to step (B).
It is preferable to further include a step of heating the structure 100 as a step prior to step (B), since this thermally cures the resin contained in the adhesive film 50, thereby more effectively preventing the adhesive film 50 from floating away from the electronic component 10 in step (B).
The temperature of the structure 100 in the step of heating the structure 100 is preferably 60° C. or higher, more preferably 80° C. or higher, even more preferably 100° C. or higher, even more preferably 120° C. or higher, even more preferably 140° C. or higher, and is preferably 230° C. or lower, more preferably 210° C. or lower, even more preferably 190° C. or lower, even more preferably 170° C. or lower.

[Step (C)]
The method for producing an electronic device of the present embodiment preferably further includes the step (C) of removing the adhesive film 50 from the electronic component 10 .
Step (C) is a step subsequent to step (B). That is, in step (C), adhesive film 50 is removed from electronic component 10 in structure 100.

The method for removing the adhesive film 50 from the electronic component 10 is not particularly limited, and may be performed, for example, by peeling the adhesive film 50 from the electronic component 10 using a known method. The peeling may be performed, for example, manually or by a device called an automatic peeling machine.

The adhesive film 50 may be peeled off from the electronic component 10 at room temperature (around 25°C), or if the automatic peeling machine has a heating function, the adhesive film 50 may be peeled off after the structure 100 has been heated to a predetermined temperature (e.g., 40°C or higher and 90°C or lower).

The surface of the electronic component 10 after peeling off the adhesive film 50 may be cleaned as necessary. Cleaning methods include wet cleaning such as water cleaning or solvent cleaning, and dry cleaning such as plasma cleaning. In the case of wet cleaning, ultrasonic cleaning may be used in combination. The cleaning method can be selected appropriately depending on the degree of contamination on the surface of the electronic component 10.

[Step (D)]
The method for manufacturing an electronic device of this embodiment preferably further includes a step (D) of backgrinding surface 10B of electronic component 10 opposite circuit-forming surface 10A.
Step (D) is a step carried out between step (A) and step (B).
"Back grinding" means to thin the electronic component 10 to a predetermined thickness without damaging the electronic component 10. For example, the structure 100 is fixed to a chuck table or the like of a grinding machine, and the surface 10B of the electronic component 10 opposite the circuit formation surface 10A is ground.

In such a back grinding operation, electronic component 10 is ground until its thickness becomes equal to or less than a desired thickness. The thickness of electronic component 10 before grinding is appropriately determined depending on the diameter, type, etc. of electronic component 10, and the thickness of electronic component 10 after grinding is appropriately determined depending on the size of the resulting chip, type of circuit, etc.
Furthermore, when the electronic component 10 is half-cut or a modified layer is formed by laser irradiation, the electronic component 10 is divided into individual chips.

The back grinding method is not particularly limited, and a known grinding method can be used. Grinding can be performed while cooling the electronic component 10 and the grindstone by pouring water on them. If necessary, a dry polishing step, which is a grinding method that does not use grinding water, can be performed at the end of the grinding step.
After the back grinding is completed, chemical etching is performed as necessary. Chemical etching is performed by immersing the electronic component 10 with the adhesive film 50 attached in an etching solution selected from the group consisting of an acidic aqueous solution consisting of a single or mixed solution of hydrofluoric acid, nitric acid, sulfuric acid, acetic acid, etc., and an alkaline aqueous solution such as a potassium hydroxide aqueous solution and a sodium hydroxide aqueous solution. Etching is performed for the purpose of removing distortion generated on the back surface of the electronic component 10, further thinning the electronic component 10, removing oxide films, etc., and pretreatment when forming an electrode on the back surface. The etching solution is appropriately selected depending on the above purpose.

[Other steps]
The method for manufacturing an electronic device according to the present embodiment may include other steps in addition to those described above. As the other steps, any method known in the art for manufacturing electronic devices may be used.
For example, any process generally performed in the manufacturing process of electronic components, such as a resist process, a developing process, an ashing process, a sputtering process, a dicing process, a die bonding process, a wire bonding process, a flip chip connection process, a cure heating test process, a sealing process, a reflow process, etc., may be further performed.

The above describes embodiments of the present invention, but these are merely examples of the present invention, and various configurations other than those described above can also be adopted.

The present invention is not limited to the above-described embodiment, and any modifications or improvements that can achieve the object of the present invention are included in the present invention.

The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited thereto.
Details regarding the preparation of the adhesive film are as follows.

<Ingredients>
Base layer 1: polyethylene naphthalate film (manufactured by Toyobo Film Solutions Co., Ltd., product name: Teonex Q81, thickness: 50 μm)
Resin 1: Ethylene-vinyl acetate copolymer (manufactured by Dow Mitsui Polychemicals, product name: Evaflex EV460, melting point: 84°C, content of structural units derived from vinyl acetate: 19% by mass, MFR (190°C, 2.16 kg): 2.5 g/10 min)
Crosslinking agent 1: Isocyanate-based crosslinking agent (manufactured by Mitsui Chemicals, Inc., product name: Olestar P49-75S)
Thermal radical polymerization initiator 1: Peroxide (manufactured by Nouryon Chemical Industries, Ltd., product name: Perkadox 12-XL25)
Photopolymerization initiator 1: α-aminoketone (manufactured by IGM Resins B.V., product name: Omnirad 379)
Multifunctional acrylate 1: Ditrimethylolpropane tetraacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., product name: AD-TMP)

<Preparation of (meth)acrylic polymer solution a>
n-Butyl acrylate (77 parts by mass), methyl methacrylate (16 parts by mass), 2-hydroxyethyl acrylate (7 parts by mass), and t-butylperoxy-2-ethylhexanoate (0.3 parts by mass) as a polymerization initiator were reacted in toluene (20 parts by mass) and ethyl acetate (80 parts by mass) at 85° C. for 10 hours. After completion of the reaction, the solution was cooled, and toluene (30 parts by mass), methacryloyloxyethyl isocyanate (7 parts by mass), and dibutyltin dilaurate (0.05 parts by mass) were added thereto, and the mixture was reacted at 85° C. for 12 hours while blowing in air, to obtain a (meth)acrylic polymer solution a.

[Example 1]
(Preparation of adhesive coating solution for thermosetting resin layer)
To 100 parts by mass of the (meth)acrylic polymer solution a (solid content), thermal radical polymerization initiator 1 (0.8 parts by mass), crosslinking agent 1 (2.56 parts by mass), and polyfunctional acrylate 1 (10 parts by mass) were added to obtain a pressure-sensitive adhesive coating liquid for a thermosetting resin layer.

(Preparation of adhesive film)
Using an extrusion molding machine, resin 1 (100 parts by mass) was extruded onto substrate layer 1. A laminated film was obtained in which a 70 μm-thick irregularity-absorbing extruded resin layer was laminated on the substrate layer.
Next, the adhesive coating liquid for the thermosetting resin layer was applied to a silicone release-treated polyethylene terephthalate film (38 μm) and dried to form a thermosetting resin layer having a thickness of 20 μm. The obtained thermosetting resin layer was then bonded to the side of the unevenness-absorbing extruded resin layer of the laminated film described above to obtain an adhesive film.

[Examples 2 to 4 and Comparative Example 2]
(Preparation of adhesive coating solution for thermosetting resin layer)
An adhesive coating liquid for a thermosetting resin layer was obtained in the same manner as in Example 1, except that the formulation of the adhesive coating liquid was as shown in Table 1.
(Preparation of adhesive film)
An adhesive film was obtained in the same manner as in Example 1, except that the thickness of the irregularity-absorbing extruded resin layer was set to a thickness shown in Table 1.
The adhesive film of Comparative Example 2 does not contain a thermal radical polymerization initiator in the thermosetting resin layer.

[Comparative Example 1]
(Preparation of Coating Solution for Thermosetting Resin Layer)
An adhesive coating liquid for a thermosetting resin layer was obtained in the same manner as in Example 1, except that the formulation of the adhesive coating liquid was as shown in Table 1.

(Preparation of adhesive film)
The adhesive coating liquid for the thermosetting resin layer was applied to a polyethylene terephthalate film (38 μm) that had been subjected to a silicone release treatment, and then dried to form a thermosetting resin layer having a thickness of 20 μm.
Next, the obtained thermosetting resin layer was attached to the base layer 1 to obtain an adhesive film.
It should be noted that Comparative Example 1 is an adhesive film that does not include an irregularity-absorbing extruded resin layer.

<Evaluation method>
(1) Evaluation of Contour-Contour Properties A bonding device (manufactured by Takatori Corporation, product name: TPL-0612W) was used to bond an adhesive film to the circuit-formed surface of a wafer (8-inch power device simulated wafer, height of circuit-formed surface (polyimide thickness): 10 μm, chip size: 10 mm × 10 mm, small pad size: 1 mm × 1 mm) under the following conditions: SP1: 800 Pa, SP2: 300 Pa, SP3: 100 Pa, bonding pressure: 0.2 MPa, bonding temperature: 100 ° C. The wafer to which the adhesive film was bonded was observed at any two points using a laser microscope (manufactured by Keyence Corporation, product name: VK-X1000) and evaluated according to the following criteria.
A (good): No lifting is observed near the 10 μm step of the polyimide. B (bad): Lifting is observed near the 10 μm step of the polyimide.

(2) Evaluation of Vacuum Resistance In the method described in (1), an adhesive film was attached to the circuit-formed surface of the wafer, and the wafer was left for at least 1 hour, and then pre-baked at 130°C for 30 minutes using a constant temperature dryer (manufactured by Yamato Scientific Co., Ltd., DN-63H). The wafer with the adhesive film attached was then heated in a vacuum constant temperature dryer (manufactured by Shimizu Rikagaku Kikai Seisakusho Co., Ltd., VOD6-4H) under conditions of vacuum pressure: 100 to 150 Pa, temperature: 150°C, and time: 15 minutes. During the heating process under reduced pressure, the presence or absence of lifting of the film was visually observed, and evaluated according to the following criteria.
A (good): No floating of 0.5 mm or more in diameter is visually observed. B (poor): Floating of 0.5 mm or more in diameter is visually observed.

Evaluations were carried out for Examples 1 to 4 and Comparative Examples 1 and 2. The results are shown in Table 1.

From Table 1, it can be seen that the adhesive film of the example has good evaluations of both unevenness-following ability and vacuum resistance. In other words, it can be seen that the adhesive film of this embodiment improves the performance balance of unevenness-following ability and vacuum resistance.

10 Electronic component 10A Circuit-forming surface of electronic component 10B Surface opposite to the circuit-forming surface of electronic component 20 Base layer 30 Irregularity-absorbing extruded resin layer 40 Thermosetting resin layer 50 Adhesive film 100 Structure

Claims (14)

An adhesive film for use in a manufacturing process of an electronic device, comprising:
The film comprises a base layer, a roughness-absorbing extruded resin layer, and a thermosetting resin layer containing a thermal radical polymerization initiator,
The unevenness-absorbing extruded resin layer and the thermosetting resin layer are in direct contact with each other. The adhesive film according to claim 1, wherein the content of the thermal radical polymerization initiator in the resin composition for forming the irregularity-absorbing extruded resin layer is less than 0.3 parts by mass when the total amount of the resin composition for forming the irregularity-absorbing extruded resin layer is 100 parts by mass. The adhesive film according to claim 1 or 2, wherein the thermal radical polymerization initiator includes a peroxide. The pressure-sensitive adhesive film according to claim 3 , wherein the peroxide contains at least one structure selected from the group consisting of the following formula (I) and the following formula (II) in its molecule.

In formula (I), the wavy lines indicate points of attachment.

In formula (II), the wavy line indicates the point of attachment. The adhesive film according to any one of claims 1 to 4, wherein the one-minute half-life temperature of the thermal radical polymerization initiator is 140°C or higher and 200°C or lower. The adhesive film according to any one of claims 1 to 5, wherein the thermal radical polymerization initiator has a hydrogen abstraction capacity of 20% or more. The adhesive film according to any one of claims 1 to 6, wherein the thermosetting resin layer is a thermosetting adhesive layer. The adhesive film according to any one of claims 1 to 7, wherein the resin constituting the thermosetting resin layer includes a (meth)acrylic resin. The adhesive film according to any one of claims 1 to 8, wherein the resin constituting the irregularity-absorbing extruded resin layer includes at least one selected from the group consisting of ethylene-vinyl acetate copolymer, (meth)acrylic resin, ethylene-α-olefin copolymer, and low-density polyethylene. The adhesive film according to any one of claims 1 to 9, wherein the thickness of the irregularity-absorbing extruded resin layer is 20 μm or more and 500 μm or less. The adhesive film according to any one of claims 1 to 10, wherein the resin constituting the base layer includes at least one selected from the group consisting of polyethylene naphthalate, polyethylene terephthalate, and polyimide. The adhesive film according to any one of claims 1 to 11, wherein the manufacturing process of the electronic device includes a step (A) of preparing a structure including an electronic component having a circuit formation surface and the adhesive film attached to the circuit formation surface side of the electronic component, and a step (B) of treating the surface of the electronic component opposite the circuit formation surface side in a vacuum atmosphere. The adhesive film according to any one of claims 1 to 12, wherein the electronic device is a power semiconductor device. A manufacturing method for manufacturing the adhesive film according to any one of claims 1 to 13,
A step of extruding the irregularity-absorbing extruded resin layer onto the base material layer;
forming the thermosetting resin layer on the irregularity-absorbing extruded resin layer using a thermosetting resin composition containing a thermal radical polymerization initiator;
The method for producing an adhesive film comprises:

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