KR-20260068088-A - Film-like adhesive, adhesive film, connection structure, and method of manufacturing a connection structure

KR20260068088AKR 20260068088 AKR20260068088 AKR 20260068088AKR-20260068088-A

Abstract

A method for manufacturing a connection structure comprises a process of laminating an adhesive film on a surface where the first electrode of a first circuit member having a first electrode is formed, and a process of arranging a second circuit member having a second electrode on the first circuit member laminated with the adhesive film so that the first electrode and the second electrode face each other, and heat-pressing the two to electrically connect the first electrode and the second electrode to each other, wherein the adhesive film comprises a film-like adhesive containing a thermoplastic resin and a radical polymerizable compound, and the film-like adhesive has a waveform of loss tangent (tanδ) obtained by measuring dynamic viscoelasticity after heating at 170°C for 5 seconds, and has multiple maximum values.

Inventors

호사카, 신타로
구도, 스나오

Assignees

가부시끼가이샤 레조낙

Dates

Publication Date: 20260513
Application Date: 20240904
Priority Date: 20230907

Claims (14)

A process of laminating an adhesive film on the surface of a first circuit member having a first electrode where the first electrode is formed, and A second circuit member having a second electrode is arranged on a first circuit member laminated with the adhesive film such that the first electrode and the second electrode face each other, and the two are heat-pressed to electrically connect the first electrode and the second electrode to each other. The above adhesive film comprises a film-like adhesive containing a thermoplastic resin and a radical polymerizable compound, and A method for manufacturing a connection structure in which the waveform of the loss tangent (tanδ) obtained by measuring dynamic viscoelasticity after heating at 170°C for 5 seconds has multiple maximum values.
In claim 1, A method for manufacturing a connection structure in which the waveform of the above loss tangent (tanδ) has a maximum value between 40℃ and 90℃.
In claim 1 or claim 2, A method for manufacturing a connection structure, wherein the waveform of the loss tangent (tanδ) has two maximum values between 40℃ and 100℃, and the difference between the two temperatures representing the maximum values is 20℃ or more and 50℃ or less.
In claim 1 or claim 2, A method for manufacturing a connecting structure in which the above thermoplastic resin contains polyester uretaine resin and phenoxy resin.
In claim 1 or claim 2, A method for manufacturing a connection structure in which the above radical polymerizable compound contains a (poly)uretain (meth)acrylate compound.
As a film adhesive containing a thermoplastic resin and a radical polymerizable compound, A film adhesive having multiple maximum values for the waveform of the loss tangent (tanδ) obtained by measuring dynamic viscoelasticity after heating at 170°C for 5 seconds.
In claim 6, A film adhesive having a waveform of the above loss tangent (tanδ) having a maximum value between 40°C and 90°C.
In claim 6, A film-like adhesive having a waveform of the loss tangent (tanδ) having two maximum values between 40°C and 100°C, and a difference between the two temperatures showing the maximum values being 20°C or more and 50°C or less.
In claim 6, The above thermoplastic resin is a film adhesive containing polyester uretaine resin and phenoxy resin.
In claim 6, The above radical polymerizable compound is a film adhesive containing a (poly)uretain (meth)acrylate compound.
In claim 6, A film-like adhesive containing additional conductive particles.
An adhesive film comprising a film-like adhesive as described in any one of claims 6 to 11.
In claim 12, An adhesive film comprising a first adhesive layer formed of the above-mentioned film-like adhesive and a second adhesive layer formed of an adhesive composition including conductive particles.
A first circuit member having a first electrode, and A second circuit member having a second electrode, and A connecting portion disposed between the first circuit member and the second circuit member and electrically connecting the first electrode and the second electrode to each other, A connection structure comprising a connection portion comprising a cured product of the film-like adhesive described in claim 12.

Description

Film-like adhesive, adhesive film, connection structure, and method of manufacturing a connection structure The present disclosure relates to a film-like adhesive, an adhesive film, a connection structure, and a method for manufacturing a connection structure. As circuit connection materials for semiconductor devices or liquid crystal display devices, thermosetting resins using epoxy resins that exhibit high adhesion and high reliability are known (see, for example, Patent Document 1). As components of the resin, epoxy resin, a curing agent such as phenolic resin that is reactive with the epoxy resin, and a latent curing agent that promotes the reaction between the epoxy resin and the curing agent are generally used. The latent curing agent is an important factor in determining the curing temperature and curing speed, and various compounds are used in terms of storage stability at room temperature and curing speed upon heating. In addition, recently, radical-curing adhesives that combine acrylate derivatives and/or methacrylate derivatives (hereinafter collectively referred to as "(meth)acrylate derivatives") with peroxides, which are radical polymerization initiators, are attracting attention. Radical curing allows for curing in a short time because the radicals, which are the reaction-active species, are highly reactive (see, for example, Patent Documents 2 and 3). For this reason, short-time curing adhesives that are advantageous for reducing production time are currently being widely used. Figure 1 is a figure for explaining the waveform of the loss tangent (tanδ). FIG. 2 is a schematic cross-sectional view showing one embodiment of an adhesive film. FIG. 3 is a schematic cross-sectional view showing one embodiment of a connection structure. Figure 4 is a schematic cross-sectional view showing the method of manufacturing the connection structure of Figure 3. Figure 5 is a figure showing an example of a binaryized image of a pressure-concentrated image taken by a differential interference microscope. In this specification, numerical ranges indicated by "~" represent a range that includes the values listed before and after "~" as minimum and maximum values, respectively. In numerical ranges described stepwise in this specification, the upper or lower limit of a numerical range in any step may be substituted with the upper or lower limit of a numerical range in another step. Furthermore, in numerical ranges described in this specification, the upper or lower limit of said numerical range may be substituted with the values shown in the examples. Additionally, individually described upper and lower limits may be combined arbitrarily. Furthermore, in this specification, "(meth)acrylate" means at least one of acrylate and the corresponding methacrylate. The same applies to other similar expressions such as "(meth)acryloyl." Also, "(poly)" means both cases where the prefix "poly" is present and where it is not. Also, "A or B" means that either one of A and B is included, or both may be included. In addition, the materials exemplified below may be used as a single type or in combination of two or more types, unless otherwise specifically stated. The content of each component in the composition refers to the total amount of said multiple substances present in the composition, unless otherwise specifically stated, in cases where multiple substances corresponding to each component exist in the composition. Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings as applicable. However, the present disclosure is not limited to the following embodiments. Film-based adhesive The film adhesive of the present embodiment comprises (A) a thermoplastic resin (hereinafter also referred to as "Component (A)") and (B) a radical polymerizable compound (hereinafter also referred to as "Component (B)"), and the waveform of the loss tangent (tanδ) obtained by measuring dynamic viscoelasticity after heating at 170°C for 5 seconds has multiple maximum values. The film adhesive of the present embodiment can exhibit sufficient adhesive strength while having excellent temporary fixation and reworkability. Furthermore, it is presumed that such effects are obtained for the following reasons. It is presumed that the adhesive exhibiting the above waveform has poor polymer compatibility in its cured product, and that by concentrating the polymer of the radical polymerizable compound, which is easy to obtain adhesive strength, into an island shape, it is possible to secure sufficient adhesive strength even with a formulation that considers adhesion. The above dynamic viscoelasticity measurement can be performed in the following steps. (i) Prepare a pre-heating sample by laminating a film-like adhesive until it reaches a thickness of about 100 μm. The thickness of each film-like adhesive laminated can be 5 to 50 μm. (ii) The sample prepared in (i) before heating is heat-cured using a heat