Conductive adhesive film and method for producing same, connector and method for producing same

Abstract

Provided is a conductive adhesive film which is capable of efficiently using conductive particles, and which is capable of ensuring conduction reliability between connected electrodes and insulativity between adjacent electrodes in response to miniaturization or narrowing pitch of the electrode size of an electronic component. The conductive adhesive film (1) has a base material (2) and an adhesive material layer (4) which is provided on one surface of the base material (2) and contains conductive particles (3), and the conductive particles (3) contained in the adhesive material layer (4) constitute a particle aggregate (5) in which a plurality of conductive particles are aggregated. In the adhesive material layer (4), array elements (6) comprising particle aggregates (5) are arranged in a predetermined array pattern corresponding to an electrode array of an electronic component (10) to which the conductive adhesive film (1) is affixed.

Description

TECHNICAL FIELD

[0001] The present technology relates to a conductive adhesive film and a manufacturing method thereof, a connection body using the conductive adhesive film to connect electronic components to each other, and a manufacturing method of the connection body. This application claims priority based on Japanese Patent Application No. 2023-87249 filed in Japan on May 26, 2023, which is hereby incorporated by reference into the present application. BACKGROUND

[0002] In the past, as a connection film for connecting various electronic components and the like, an anisotropic conductive film (ACF) has been known.

[0003] PRIOR ART DOCUMENTS PATENT DOCUMENTS Patent Document 1: Japanese Patent Application Publication No. 2020-198422; Patent Document 2: Japanese Patent No. 6489516. SUMMARY

[0004] PROBLEMS TO BE SOLVED BY THE INVENTION The ACF has conductive particles uniformly dispersed in an adhesive material layer, and thus the conductive particles that contribute to the conductive connection are only a part of the conductive particles captured on the electrodes, and the conductive particles other than the conductive particles captured on the electrodes do not contribute to the conductive connection and are wasted. In addition, a particle-regularly-aligned ACF in which relatively large conductive particles having an average particle diameter of 15 to 20 pm are regularly aligned has been proposed, but in the particle-regularly-aligned ACF as well, as in the dispersed ACF, the conductive particles other than the conductive particles captured on the electrodes do not contribute to the conductive connection, and the conductive particles are not used efficiently. A proposal in which the ACF is processed into a shape corresponding to the shape of a substrate or an electrode arrangement pattern to which the ACF is attached and is provided has also been proposed (for example, see Patent Document 1), but it is inevitable that the conductive particles that are present at positions other than the electrodes are present.

[0005] In addition, if the electrode size of the electronic components connected by the anisotropic conductive film is further reduced, the number of conductive particles that can be captured by the electrodes is also further reduced, and the conventional anisotropic conductive film sometimes fails to sufficiently obtain the conductive reliability. On the other hand, for example, as a trend in the production of an ACF for a camera module (CCM), further high pixelization or high transmission is required, and as the anisotropic conductive film, it is also required to increase the particle density in order to correspond to further narrow pitch, to arrange more conductive particles on the electrodes, to improve the conductive reliability, and to prevent short-circuiting caused by the interposition of the conductive particles between adjacent electrodes.

[0006] Therefore, the purpose of this technology is to provide a conductive adhesive film, a method for manufacturing the conductive adhesive film, a connector, and a method for manufacturing the connector. The conductive adhesive film can efficiently utilize conductive particles and can correspond to the miniaturization or narrow spacing of the electrode size of electronic components, ensuring the reliability of conduction between connected electrodes and the insulation between adjacent electrodes.

[0007] Solution for solving the problem To address the aforementioned issues, the conductive adhesive film of this invention comprises a substrate and an adhesive material layer containing conductive particles disposed on one side of the substrate. The conductive particles contained in the adhesive material layer constitute a particle agglomerate formed by agglomerating multiple conductive particles. The adhesive material layer has arrangement elements composed of the particle agglomerate arranged in a predetermined pattern corresponding to the electrode arrangement of the electronic component to which the conductive adhesive film is attached.

[0008] Furthermore, regarding the manufacturing method of the conductive adhesive film involved in this technology, in the manufacturing method of the conductive adhesive film having a substrate and an adhesive material layer having conductive particles disposed on one side of the substrate, there is an arrangement step in which arrangement elements composed of particle aggregates formed by agglomerating a plurality of the aforementioned conductive particles are arranged in a predetermined arrangement pattern corresponding to the electrode arrangement of the electronic component to which the conductive adhesive film is attached are arranged in the aforementioned adhesive material layer. The aforementioned arrangement step involves disposing the aforementioned conductive particles in the aforementioned adhesive material layer through a mask having predetermined openings.

[0009] Furthermore, regarding the connector involved in this technology, in the connector that connects the first electronic component and the second electronic component via a conductive adhesive film containing multiple conductive particles, the aforementioned conductive adhesive film has a substrate and an adhesive material layer disposed on one side of the aforementioned substrate and containing conductive particles. The aforementioned conductive particles contained in the aforementioned adhesive material layer constitute a particle agglomerate formed by agglomerating multiple aforementioned conductive particles. The aforementioned adhesive material layer has arrangement elements composed of the aforementioned particle agglomerate arranged in a predetermined arrangement pattern corresponding to the electrode arrangement of the aforementioned first electronic component to which the aforementioned conductive adhesive film is attached.

[0010] Furthermore, the manufacturing method of the connector involved in this technology includes a configuration step of attaching a conductive adhesive film containing multiple conductive particles to a first electronic component and a connection step of connecting the first electronic component and a second electronic component via the aforementioned conductive adhesive film. The aforementioned conductive adhesive film has a substrate and an adhesive material layer disposed on one side of the aforementioned substrate and containing conductive particles. The aforementioned conductive particles contained in the aforementioned adhesive material layer constitute a particle agglomerate formed by agglomerating multiple aforementioned conductive particles. The aforementioned adhesive material layer has arrangement elements composed of the aforementioned particle agglomerates arranged in a predetermined arrangement pattern corresponding to the electrode arrangement of the aforementioned first electronic component to which the aforementioned conductive adhesive film is attached. In the aforementioned configuration step, the electrodes of the aforementioned first electronic component are aligned with the aforementioned arrangement elements, and the aforementioned conductive adhesive film is attached to the aforementioned first electronic component.

[0011] Invention Effects According to this technology, the arrangement elements of the conductive adhesive film are composed of aggregates of conductive particles, thus making it easier to form an arrangement pattern than when the conductive particles are disposed individually. Furthermore, by arranging the arrangement elements in a desired pattern in specific portions of the adhesive layer, it is possible to reduce wasted conductive particles that do not contribute to conductivity or conductive particles located between adjacent electrodes, effectively balancing improved conductivity between connected electrodes and prevention of short circuits between adjacent electrodes even with narrow spacing. Attached Figure Description

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[0032] Hereinafter, with reference to the accompanying drawings, the conductive adhesive film to which this technology is applied, the method for manufacturing the conductive adhesive film, the connector, and the method for manufacturing the connector will be described in detail. Furthermore, this technology is not limited to the embodiments described below, and various modifications can be made without departing from the spirit of this technology. Additionally, the drawings are schematic, and the proportions of various dimensions may sometimes differ from actual dimensions. Specific dimensions should be determined by referring to the following description. Furthermore, this also includes portions in the drawings where the dimensional relationships or proportions differ from each other.

[0033] Conductive adhesive film Figure 1 (A) is a top view showing the conductive adhesive film 1 with the arrangement of the 6 elements arranged in a predetermined pattern. Figure 1 (B) is a top view showing the conductive particle condensate 5 that constitutes the arrangement element 6. Figure 1 (C) is a top view showing the conductive particles 3 that constitute the conductive particle aggregate 5.

[0034] The conductive adhesive film 1 to which this technology is applied has a substrate 2 and an adhesive material layer 4 disposed on one side of the substrate 2 and containing conductive particles 3. The conductive particles 3 contained in the adhesive material layer 4 constitute a particle agglomerate 5 formed by agglomerating multiple conductive particles 3. The adhesive material layer 4 has arrangement elements 6 composed of particle agglomerates 5 arranged in a predetermined arrangement pattern corresponding to the electrode arrangement of the first electronic component 10 to which the conductive adhesive film 1 is attached.

[0035] A conductive adhesive film 1 has an adhesive material layer 4 continuously disposed along the length direction of the substrate 2. The adhesive material layer 4 has arrangement elements 6 composed of particle aggregates 5 arranged in a predetermined pattern corresponding to the electrode arrangement of the first electronic component 10. Furthermore, the conductive adhesive film 1 aligns the electrodes 11 of the first electronic component 10 (which is the adherend) with the arrangement elements 6, and then adheres the adhesive material layer 4 to the first electronic component 10. Subsequently, after aligning the electrodes 11 of the first electronic component 10 with the electrodes 13 of the second electronic component 12, the first electronic component 10 and the second electronic component 12 are connected via the conductive adhesive film 1.

[0036] Figure 2 This is a schematic cross-sectional view showing the state in which the conductive adhesive film 1 is pasted on the electrode arrangement of the first electronic component 10, aligned with the arrangement element 6. Figure 3 This is a schematic top view showing the state in which the conductive adhesive film 1 is pasted onto the electrode arrangement of the first electronic component 10 with the arrangement elements 6 aligned. Conductive particle aggregates 5 are densely clustered in a predetermined area corresponding to the electrodes 11 of the first electronic component 10, thereby forming... Figure 2 and Figure 3 The conductive adhesive film 1 shown is arranged in element 6.

[0037] Based on the conductive adhesive film 1 to which this technology is applied, an arrangement pattern of arrangement elements 6 composed of particle aggregates 5 is designed to match the electrode design of the first electronic component 10 to which it is attached. In this case, the arrangement elements 6 are composed of aggregates of conductive particles 3, thus it is easier to form an arrangement pattern than if the conductive particles 3 were disposed of individually.

[0038] Furthermore, by arranging the elements 6 in a desired pattern on specific portions of the adhesive layer 4, conductive particles 3 can be efficiently disposed on the electrodes 11 of the first electronic component 10, reducing or eliminating wasteful conductive particles 3 that do not contribute to conductivity or conductive particles 3 located between adjacent electrodes. Therefore, efficient utilization of the conductive particles 3 is achieved, and even when the electrodes 11 and 13 of the first and second electronic components 11 and 12 are spaced narrowly, the conductivity between the connecting electrodes of electrodes 11 and 12 is improved, and the risk of short circuits between adjacent electrodes is reduced.

[0039] Furthermore, based on the conductive adhesive film 1 to which this technology is applied, the minimum connection area between connecting electrodes in anisotropic conductive connections can be further reduced. That is, conventionally, as a means of ensuring conductivity between miniaturized electrodes, a certain electrode area is required to capture the conductive particles necessary to establish stable conductivity. However, according to this technology, by concentrating the conductive particle aggregates 5 on the electrodes 11, conductivity can be ensured, and stable conductivity can be established even with a miniaturized electrode area. Therefore, the minimum connection area between connecting electrodes in anisotropic conductive connections can be further reduced.

[0040] Furthermore, according to the conductive adhesive film 1 to which this technology is applied, by concentrating the conductive particle aggregates 5 on the electrode 11, the density of conductive particles 3 captured between the connecting electrodes can be increased. Therefore, compared to a dispersed conductive adhesive film in which conductive particles are dispersed across the entire surface of the adhesive layer, or a neatly arranged conductive adhesive film in which conductive particles are evenly distributed across the entire surface of the adhesive layer, a lower resistance can be achieved in the conduction resistance between the connecting electrodes.

[0041] Furthermore, in this technology, the arrangement elements 6 of the conductive adhesive film 1 are not treated as individual conductive particles, but rather as aggregates 5 of conductive particles 3. Therefore, the aggregates 5 constituting the arrangement elements 6 do not require high uniformity with respect to individual conductive particles 3. This increases the freedom of choice in selecting the conductive particles 3. For example, metal particles with inconsistent particle sizes, such as solder particles, can be used as conductive particles 3. Moreover, by treating the arrangement elements 6 as aggregates 5 of conductive particles, even when the particle sizes of the conductive particles 3 are not uniform, it is easy to neatly arrange the arrangement elements 6 in accordance with the pattern of the electrodes 11 of the first electronic component 10.

[0042] Furthermore, if one wants to form an arrangement pattern by arranging conductive particles one by one in predetermined positions, mimicking the neatly arranged anisotropic conductive film, it requires creating a prototype of the arrangement pattern of each conductive particle according to each electrode pattern, or requires highly complex micro-machining, leading to increased manufacturing costs and difficulty in flexibly corresponding to the patterns of the connecting electrodes. However, according to the conductive adhesive film 1 using this technology, the arrangement element 6 is treated as an aggregate 5 of conductive particles 3, thus eliminating the need for micro-machining to the extent of arranging each conductive particle, and allowing for flexible formation of arrangement patterns corresponding to various connecting electrode patterns, including from an economic perspective.

[0043] [Mono-chip] In addition to the adhesive material layer 4 continuously disposed along the length direction of the substrate 2, the conductive adhesive film 1 also includes, for example... Figure 4 , Figure 5As shown, the adhesive material layer 4, which has arrangement elements 6 arranged in accordance with the electrode pattern of the first electronic component 10, can also be monolithically formed corresponding to the bonding area of ​​the first electronic component 10 where the conductive adhesive film 1 is bonded. Figure 4 , Figure 5 The conductive adhesive film 1 shown has repeatedly arranged individual pieces 8 along the length direction of the substrate 2, corresponding to the bonding area of ​​the first electronic component 10. Each individual piece 8 has arrangement elements 6 arranged in a pattern corresponding to the electrode pattern of the first electronic component 10. The conductive adhesive film 1 aligns the electrodes 11 of the first electronic component 10, which is the adherend, with the arrangement elements 6 for each individual piece 8, and then adheres the adhesive material layer 4 to the first electronic component 10.

[0044] Figure 4 (A) and (B) are top views showing a conductive adhesive film 1 having a single sheet 8 composed of multiple arranged elements 6. Figure 4 Each piece 8 of the conductive adhesive film 1 shown in (A) and (B) aligns the arrangement elements 6 and is attached to the electrode 11 of the first electronic component 10, which has one or more electrodes 11 separately disposed in the adhesive area.

[0045] Figure 5 (A) is shown to be related to Figure 5 (B) is a top view of the conductive adhesive film 1 with arrangement element 6 corresponding to the electrode arrangement of the first electronic component 10. Figure 5 (B) The first electronic component 10 has a first terminal row 21, a second terminal row 22, or a third terminal row 23 with terminals (electrodes 11) arranged on each of the three sides of the rectangular pasting area. Regarding Figure 5 (A) The conductive adhesive film 1 has an arrangement element 6 arranged in a manner corresponding to each terminal of the first to third terminal rows 21 to 23 formed in the adhesive area of ​​each first electronic component 10. Each arrangement element 6 is aligned and pasted onto the terminal of the first electronic component 10.

[0046] also, Figure 5 (A) The conductive adhesive film 1 shown in the diagram does not have an adhesive material layer 4 applied to the entire rectangular bonding area of ​​each individual piece 8. Instead, the adhesive material layer 4 is applied along three sides, resulting in a roughly U-shaped structure that opens from the center of the bonding area to one side where no terminal array is formed. This prevents the center of the bonding area from being sealed by the adhesive material layer 4 and reduces the amount of adhesive material layer 4 used. Furthermore, the shape of the bonding area matches the shape of the individual piece 8 at necessary points, thereby suppressing excessive overflow of unwanted resin after the individual pieces 8 are bonded.

[0047] [Arrangement Elements] In addition, the arrangement element 6 constituting the arrangement pattern can be composed of one or two particle aggregates 5, in addition to being composed of multiple particle aggregates 5 densely packed together. Figure 6 (A) The conductive adhesive film 1 has an arrangement element 6 consisting of a particle aggregate 5 arranged in a predetermined arrangement pattern corresponding to the electrode arrangement of the first electronic component 10 on the adhesive material layer 4. Figure 6 (B) The conductive adhesive film 1 shown is a structure in which the adhesive material layer 4 is monolithically attached to the bonding area of ​​the first electronic component 10, and each monolith 8 is provided with an arrangement element 6 consisting of a particle aggregate 5. Figure 6 The conductive adhesive film 1 shown in (A) and (B) is aligned such that the particle aggregate 5 is disposed at the center of the electrode 11 in the width direction.

[0048] Figure 7 (A) The conductive adhesive film 1 has an arrangement element 6 consisting of two particle aggregates 5 arranged in a predetermined pattern corresponding to the electrode arrangement of the first electronic component 10 on the adhesive material layer 4. Figure 7 (B) The conductive adhesive film 1 shown is a structure in which the adhesive material layer 4 is monolithically attached to the bonding area of ​​the first electronic component 10, and each monolith 8 is provided with an arrangement element 6 consisting of two particle aggregates 5. Figure 7 The conductive adhesive film 1 shown in (A) and (B) is aligned such that two particle aggregates 5 are disposed at the center of the electrode 11 in the width direction.

[0049] In addition, when the conductive adhesive film 1 is composed of multiple particle aggregates 5 forming the arrangement element 6, the particle aggregates 5 can also be arranged regularly and neatly. Figure 8 (A) is a top view of a conductive adhesive film 1 in which particle aggregates 5 are arranged in a hexagonal grid pattern in a predetermined pattern corresponding to the electrode arrangement of the first electronic component 10. Figure 8 (B) shows the composition Figure 8 (A) is a top view of the arrangement of conductive particle aggregates 5 of each arrangement element 6 of the conductive adhesive film 1 shown. Figure 8 (C) is a top view showing the condensation 5 of each conductive particle constituting the arrangement element 6. Figure 8 In the conductive adhesive film 1 shown, the adhesive material layer 4 can also be monolithically separated from the bonding area of ​​the first electronic component 10. Besides... Figure 8 Apart from the configuration shown in (B), in the aforementioned Figure 4 In the configurations shown in (A) and (B), the conductive particle aggregates 5 constituting the arrangement element 6 can also be arranged neatly.

[0050] Furthermore, the area of ​​the arrangement element 6 can also be set to be less than or equal to the area of ​​the electrode of the first electronic component 10. The arrangement element 6 is formed by filling or neatly arranging the conductive particle aggregate 5 through the opening 34 of the mask 33 (described later) onto the adhesive material layer 4. That is, the maximum area or shape of the arrangement element 6 is defined by the area or shape of the opening 34 of the mask 33. For example, by making the opening 34 corresponding to the rectangular electrode 11 with the same rectangular shape as the electrode 11, an arrangement element 6 with the same area and shape as the electrode 11 is formed. Alternatively, by making the opening 34 smaller than the electrode 11, an arrangement element 6 with an area smaller than the electrode area is formed. Therefore, the area of ​​the arrangement element 6 refers to the maximum area defined by the opening 34 of the mask 33.

[0051] Furthermore, the area of ​​the arrangement element 6 is set to be less than or equal to the area of ​​the electrode 11 of the first electronic component 10, thereby allowing for tolerance of alignment misalignment between the arrangement element 6 and the electrode. That is, when the conductive adhesive film 1 is adhered to the adhesion area of ​​the first electronic component 10, the electrode 11 of the first electronic component 10 is aligned with the arrangement element 6, but if an alignment misalignment occurs, the conductive particle aggregate 5 constituting the arrangement element 6 overflows into the gap between adjacent electrodes, and depending on the amount of overflow, there is a possibility of a short circuit between adjacent electrodes.

[0052] Therefore, the area of ​​the arrangement element 6 is set to be less than or equal to the area of ​​the electrode 11 of the first electronic component 10. This prevents the conductive particle aggregate 5 from overflowing into the gap between adjacent electrodes, or suppresses the overflow amount, even if there is an alignment misalignment between the arrangement element 6 and the electrode 11, thus reducing the risk of short circuits between adjacent electrodes. Furthermore, since the arrangement element 6 is composed of conductive particle aggregates 5, even if a portion of the conductive particle aggregates 5 overflows into the gap between adjacent electrodes, sufficient conductivity between the connecting electrodes can be ensured by the conductive particle aggregates 5 located on the electrode 11.

[0053] Figure 9 The diagram shows a state in which the particle aggregate 5 is prevented from overflowing between adjacent electrodes even when the area of ​​the arrangement element 6 is smaller than the area of ​​the electrode 11 of the first electronic component 10, even when the alignment offset between the arrangement element 6 and the electrode 11 occurs. (A) is a cross-sectional view and (B) is a top view.

[0054] Figure 10 It is shown Figure 6The diagrams shown in (A) and (B) depict the state in which the arrangement element 6 (conductive particle aggregate 5) of the conductive adhesive film 1 is disposed on the electrode 11. (A) is a top view showing the state in which the arrangement element 6 (conductive particle aggregate 5) is disposed at the center of the electrode 11 in the width direction without any alignment offset. (B) is a top view showing the state in which the arrangement element 6 (conductive particle aggregate 5) is offset along the width direction of the electrode 11 due to the offset of the adhesive position of the conductive adhesive film 1.

[0055] Figure 11 It is shown Figure 7 The diagrams shown in (A) and (B) depict the state in which the arrangement element 6 (conductive particle aggregate 5) of the conductive adhesive film 1 is disposed on the electrode 11. (A) is a top view showing the state in which the arrangement element 6 (two conductive particle aggregates 5) is disposed at the center of the electrode 11 in the width direction without any alignment offset. (B) is a top view showing the state in which the arrangement element 6 (two conductive particle aggregates 5) is offset along the width direction of the electrode 11 due to the offset of the adhesive position of the conductive adhesive film 1.

[0056] Figure 10 (B) Figure 11 (B) Any one of them suppresses the amount of particle condensate 5 overflowing between adjacent electrodes, preventing short circuits between adjacent electrodes.

[0057] Furthermore, when setting the arrangement direction of arrangement element 6 in the arrangement pattern to the width direction of arrangement element 6 and setting the arrangement direction of electrode 11 in the electrode arrangement of the first electronic component 10 to the width direction of electrode 11, it is preferable to set the width W1 of arrangement element 6 to 40% or more and 100% or less of the width W2 of electrode 11. The state where the width W1 of arrangement element 6 is 100% of the width W2 of electrode 11 means that the width of arrangement element 6 is the same as the width of electrode 11. If it exceeds 100%, even a slight alignment misalignment could create a risk of short circuits between adjacent electrodes. Figure 12 This is a top view showing the alignment misalignment that occurs when the width W1 of the arrangement element 6, which is composed of aggregates 5 of conductive particles 3 with an average particle size of 20 μm, is set to 200 μm, the same width as the width W2 of the electrode 11. When the gap S between adjacent electrodes is set to 200 μm, a slight misalignment (about 160 μm) is allowed while ensuring conductivity between the connecting electrodes and preventing short circuits between adjacent electrodes.

[0058] Furthermore, the state where the width W1 of the so-called arrangement element 6 is 40% of the width W2 of the electrode 11, for example, is equivalent to... Figure 6 (A) (B) and Figure 7In the conductive adhesive film 1 shown in (A) and (B), the particle size of the conductive particle aggregate 5 (the average particle size of the conductive particles 3 is 20 μm) is set to 80 μm, and the width of the electrode 11 of the first electronic component 10 is set to 200 μm. When the state in which the conductive particle aggregate 5 is disposed at the center in the width direction of the electrode 11 is set to the ideal state where there is no alignment misalignment (refer to...). Figure 10 (A) Figure 11 (A) Even with an alignment offset of about half the width (100 μm) of the electrode 11, a portion of the conductive particle condensate 5 is on the electrode 11, which ensures conduction between the connected electrodes and prevents short circuits between adjacent electrodes.

[0059] Conductive adhesive film The components of the conductive adhesive film 1 will be described in detail below. As described above, the conductive adhesive film 1 has a substrate 2 and an adhesive material layer 4 disposed on one side of the substrate 2 and containing conductive particles 3. In addition, the conductive particles 3 contained in the adhesive material layer 4 constitute a particle agglomerate 5 formed by agglomerating multiple conductive particles 3.

[0060] Substrate The conductive adhesive film 1 is provided in a roll as a film roll body 30. Figure 13 This is a schematic three-dimensional view of the membrane roll. (For example...) Figure 13 As shown, the film roll 30 is formed by winding a conductive adhesive film 1, which has a strip-shaped substrate 2 and an adhesive layer 4 formed on the substrate 2, onto a core 31. The core 31 has a shaft hole for inserting a rotating shaft for rotating the roll, and one end of the conductive adhesive film 1 in the longitudinal direction is connected to it and the conductive adhesive film 1 is wound around it. The length of the conductive adhesive film 1 wound on the film roll 30 is not particularly limited, and conductive adhesive films with a lower limit of 5m or more, 10m or more, or 50m or more, and an upper limit of 5000m or less, 3000m or less, or 1000m or less, can be used appropriately.

[0061] The substrate 2 is a support film formed in a strip shape that supports the adhesive layer 4. Examples of substrate 2 include PET (Polyethylene Terephthalate), OPP (Oriented Polypropylene), PMP (Poly-4-methylpentene-1), and PTFE (Polytetrafluoroethylene). Alternatively, the substrate 2 can be a substrate for example, one where at least one side of the adhesive layer 4 has been peeled off using silicone resin.

[0062] The thickness of the substrate 2 is not particularly limited. The lower limit of the thickness of the substrate 2, in order to separate it from the adhesive layer 4, is preferably 10 μm or more, more preferably 25 μm or more, and even more preferably 38 μm or more. If the upper limit of the thickness of the substrate 2 is too thick, there is concern that excessive pressure may be applied to the adhesive layer 4; therefore, it is preferably 200 μm or less, more preferably 100 μm or less, and even more preferably 75 μm or less. It can also be set to 50 μm or less.

[0063] Furthermore, the width of the substrate 2 is not particularly limited. The lower limit of the width of the substrate 2 is preferably 1 mm or more during winding, more preferably 2 mm or more, and even more preferably 4 mm or more. If the upper limit of the substrate width is too large, it may cause difficulties in handling or operation; therefore, it can be 250 mm or less, preferably 120 mm or less, more preferably 60 mm or less, and even more preferably 10 mm or less. The width of the substrate 2 can be adjusted appropriately according to the arrangement pattern of the arrangement elements 6. Furthermore, for productivity reasons, it is preferable that the width of the substrate 2 and the width of the adhesive layer 4 are set to the same width, with the ends aligned in the width direction.

[0064] [Adhesive Material Layer] The adhesive layer 4, supported by the substrate 2, is a connecting film used for conductive connection between the first electronic component 10 and the second electronic component. There are no particular limitations on the curing type of the adhesive layer 4; examples include thermosetting, photocuring, and combined photothermal and photocuring types. Alternatively, the adhesive layer 4 can also be a hot-melt type using a thermoplastic resin.

[0065] The following description uses an anisotropic conductive film containing aggregates 5 of conductive particles 3 in an insulating adhesive as an example. The lower limit of the thickness of the anisotropic conductive film can, for example, be the same as the conductive particle size, and is preferably set to at least 1.3 times the conductive particle size or at least 10 μm. Furthermore, the upper limit of the thickness of the anisotropic conductive film can, for example, be set to at least 40 μm or less or at least twice the conductive particle size. Additionally, the anisotropic conductive film can be made by laminating insulating adhesive layers or adhesive layers that do not contain conductive particles 3, and the number of layers or the lamination surfaces can be appropriately selected to match the object or purpose. Furthermore, the insulating resin used as the insulating adhesive layer or adhesive layer can be the same insulating resin as that used in the anisotropic conductive film. As described above, the conductive particle aggregates 5 can be dispersed in the resin or arranged in an orderly manner. Furthermore, when the conductive particle aggregates 5 are dispersed in the resin, they can be in close contact or separated in a non-contact manner.

[0066] Insulating adhesives (insulating resins) can utilize known insulating adhesives. Examples of curing types include thermosetting, photocuring, and combined photo-thermal curing types. Examples include photoradical polymerization resin compositions containing (meth)acrylate compounds and photoradical polymerization initiators, thermal radical polymerization resin compositions containing (meth)acrylate compounds and thermal radical polymerization initiators, thermal cationic polymerization resin compositions containing epoxy compounds and thermal cationic polymerization initiators, and thermal anionic polymerization resin compositions containing epoxy compounds and thermal anionic polymerization initiators. Furthermore, known adhesive compositions can also be used. In the case of hot-melt adhesives, the composition disclosed in Japanese Patent Application Publication No. 2014-060025 can be used.

[0067] The following is a specific example of a thermally free radical polymerized insulating adhesive containing a film-forming resin, an elastomer, a (meth)acrylic acid monomer, a polymerization initiator, and a silane coupling agent. Furthermore, (meth)acrylic acid monomer refers to either an acrylic acid monomer or a methacrylic acid monomer.

[0068] There are no particular limitations on the film-forming resin used; examples include phenoxy resins, unsaturated polyester resins, saturated polyester resins, polyurethane resins, butadiene resins, polyimide resins, polyamide resins, and polyolefin resins. One type of film-forming resin can be used alone, or two or more can be used in combination. Among these, phenoxy resins are particularly preferred from the viewpoints of film-forming properties, processability, and bonding reliability. Phenoxy resins are resins synthesized from bisphenol A and epichlorohydrin; both appropriately synthesized resins and commercially available products can be used. There are no particular limitations on the content of the film-forming resin; for example, 10% to 60% by mass is preferred.

[0069] As an elastomer, there are no particular limitations; examples include polyurethane resin (polyurethane elastomer), acrylic rubber, silicone rubber, butadiene rubber, etc.

[0070] There are no particular limitations on the (meth)acrylic acid monomer; for example, it can be a monofunctional (meth)acrylic acid monomer or a polyfunctional (meth)acrylic acid monomer with two or more functions. From the viewpoint of stress relief of the polymer, it is preferable that 80% or more by mass of the (meth)acrylic acid monomer in the insulating adhesive is a monofunctional (meth)acrylic acid monomer.

[0071] Furthermore, from the viewpoint of adhesion, the monofunctional (meth)acrylic acid monomer preferably contains a carboxylic acid. Additionally, the molecular weight of the monofunctional (meth)acrylic acid monomer containing a carboxylic acid is preferably 100 to 500, more preferably 200 to 350. Furthermore, the content of the monofunctional (meth)acrylic acid monomer containing a carboxylic acid in the insulating adhesive is preferably 3% to 20% by mass, more preferably 5% to 10% by mass.

[0072] There are no particular limitations on the polymerization initiator, as long as it can cure (meth)acrylic acid monomers at a predetermined temperature during hot pressing. Examples of organic peroxides include lauroyl peroxide, butyl peroxide, benzyl peroxide, dilauroyl peroxide, dibutyl peroxide, dicarbonate peroxide, and benzoyl peroxide. One or more of these can be used individually or in combination. There are no particular limitations on the amount of the polymerization initiator in the insulating adhesive, but it is preferably from 0.5% to 15% by mass.

[0073] There are no particular limitations on the silane coupling agent used; examples include epoxy silane coupling agents, acrylic silane coupling agents, thiol silane coupling agents, and amine silane coupling agents. The content of the silane coupling agent in the insulating adhesive is not particularly limited, but is preferably from 0.1% to 5.0% by mass.

[0074]

Conductive particles

[0075] The particle size of the conductive particles 3 is not particularly limited, but the lower limit of the particle size is preferably 2 μm or more, and the upper limit of the particle size, for example from the viewpoint of the thickness of the adhesive layer 4, is preferably 50 μm or less, and more preferably 20 μm or less. Furthermore, the particle size of the conductive particles 3 can be set to a value measured by an image-type particle size analyzer (as an example, FPIA-3000: manufactured by Malvern). This number is preferably 1000 or more, and more preferably 2000 or more.

[0076]

Particle condensation / arrangement elements

[0077] The diameter of the conductive particle aggregate 5 is not particularly limited, but the lower limit is preferably more than twice the particle size of the conductive particles 3. Furthermore, the upper limit of the diameter of the conductive particle aggregate 5, from the viewpoint of the capture efficiency of the conductive particle aggregate 5 in the connector and the insulation resistance between adjacent electrodes, is preferably less than three times, and more preferably less than four times. For example, when the particle size is 2 μm, the lower limit of the aggregate diameter is preferably 4 μm or more, and the upper limit is preferably 6 μm or less, and more preferably 8 μm or less. Furthermore, when the particle size is 20 μm, the lower limit of the aggregate diameter is preferably 40 μm or more, and the upper limit is preferably 60 μm or less, and more preferably 80 μm or less. In addition, the diameter of the conductive particle aggregate 5 can also be measured using the same method as the particle size of the conductive particles 3. The number of measurements is preferably 5 or more, and more preferably 10 or more.

[0078] As described above, arrangement elements 6 are formed by aggregating one or more conductive particle aggregates 5. The conductive particle aggregates 5 in each arrangement element 6 can be densely packed or dispersed separately, or they can be arranged neatly. There are no particular restrictions on the neat arrangement pattern; it can be striped or grid-like, with a hexagonal grid pattern being particularly preferred.

[0079] Furthermore, the arrangement pattern of the arrangement element 6 corresponds to the arrangement pattern of the electrode 11 of the first electronic component 10, and is arranged in the same direction and with the same spacing as the arrangement pattern of the electrode 11. Moreover, the arrangement element 6 is aligned with the electrode 11 of the first electronic component 10, so that a number of conductive particle aggregates 5 overlap the entire surface of the electrode 11, or one or more conductive particle aggregates 5 are dispersed or neatly arranged in the electrode 11.

[0080] Manufacturing process of conductive adhesive film Next, the manufacturing process of the conductive adhesive film 1 will be described. The manufacturing process of the conductive adhesive film 1 includes a method for manufacturing a conductive adhesive film having a substrate 2 and an adhesive material layer 4 containing conductive particles 3 disposed on one side of the substrate 2. This method includes an arrangement step where arrangement elements 6, composed of particle aggregates 5 formed by agglomerating multiple conductive particles 3, are arranged on the adhesive material layer 4 in a predetermined arrangement pattern corresponding to the electrode arrangement of the first electronic component 10 to which the conductive adhesive film 1 is adhered. In this arrangement step, conductive particles 3 are printed onto the adhesive material layer 4 through a mask 33 having predetermined openings 34, thereby setting the arrangement elements 6.

[0081] The above-mentioned insulating adhesive and other adhesive resin composition can be applied to a substrate 2 such as a PET film and dried at a predetermined temperature, thereby setting the adhesive material layer 4 on the substrate 2.

[0082] On the adhesive material layer 4 supported by the substrate 2, arrangement elements 6 composed of conductive particle aggregates 5 are arranged in a predetermined pattern. As the mask 33 used in this arrangement process, a known metal mask 33a (see [reference]) can be used. Figure 14 The opening diameter of the opening 34 of the mask 33 is set to be more than 200% of the average particle size of the conductive particles 3, thereby enabling the formation of conductive particle aggregates 5 by filling the adhesive layer 4 with conductive particles 3 through the opening 34. Furthermore, by using the rotating screen 33b as the mask 33, arrangement elements 6 can be continuously formed along the length direction of the adhesive layer 4 (see reference). Figure 15 ).

[0083] The processing of the openings 34 that allow the conductive particle aggregates 5 to be arranged can be performed easily and at low cost, and a mask 33 corresponding to a predetermined arrangement pattern corresponding to the electrode arrangement of various first electronic components 10 can be prepared. In addition, the area of ​​the arrangement elements 6 can be easily adjusted to predict the alignment offset of the narrow-pitch electrode pattern.

[0084] When the adhesive material layer 4 with arrangement elements 6 is made into a single sheet, a predetermined single sheet 8 is formed by performing half-cutting, punching, and stamping processes on the conductive adhesive film 1. Alternatively, the adhesive material layer 4 on the substrate 2 can be removed by processing only. Furthermore, a process of setting a cover film on the adhesive material layer 4 can also be provided. Therefore, the aforementioned processing can be performed on the substrate 2 and the adhesive material layer 4 using the cover film as a support (instead of the substrate 2). As described above, the substrate 2 is peeled (separated) from the adhesive material layer 4 during use, thus the processing technology is difficult. The material of the cover film can also be the same as the substrate 2 described above. The thickness is preferably thinner than that of the substrate 2.

[0085] [Connector] The connector 40 to which this technology is applied is configured to connect the first electronic component 10 and the second electronic component 12 via a conductive adhesive film 1. In this specification, the electronic component to which the conductive adhesive film 1 is adhered in the first and second electronic components 10 and 12 that are joined together is designated as the first electronic component 10.

[0086]

Electronic Component 1 / Electronic Component 2

[0087] Furthermore, the connectors and manufacturing methods involved in this technology can be used in, for example, semiconductor devices (devices that utilize semiconductor elements such as optical elements, thermoelectric conversion elements, and photoelectric conversion elements, in addition to driver ICs), display devices (monitors, televisions, head-mounted displays, etc.), portable devices (tablet terminals, smartphones, wearable terminals, etc.), game consoles, audio equipment, camera devices (devices using image sensors such as camera modules), electrical components for vehicles (mobile devices), medical devices, sensor devices (touch sensors, fingerprint authentication, iris authentication, etc.), home appliances, and all electronic devices that use electrical connections, as well as their manufacturing methods.

[0088] [Manufacturing process of connector] The manufacturing process of connector 40 includes: a configuration process in which a conductive adhesive film 1 is adhered to a first electronic component 10; and a connection process in which a second electronic component 12 is disposed on the conductive adhesive film 1, and the first electronic component 10 and the second electronic component 12 are connected via the conductive adhesive film 1.

[0089]

Configuration Process

[0090]

Connection Process

[0091] Figure 18 This is a cross-sectional view showing the connection process of connecting the second electronic component 12 to the first electronic component 10 via adhesive layer 4. Figure 18 As shown, in the connection process, for example, a crimping tool 42 is used to press the electrode 11 of the first electronic component 10 and the electrode 13 of the second electronic component 12 via a cushioning material 41. In addition, heating, light irradiation, etc., are performed in accordance with the curing type of the adhesive layer 4 to cure the adhesive layer 4, thereby connecting the first electronic component 10 and the second electronic component 12.

[0092] Figure 19 This is a cross-sectional view showing the connector 40 that connects the first electronic component 10 and the second electronic component 12 via the cured film 4a after the adhesive layer 4 has cured. Figure 19As shown, the connector 40 electrically connects the electrode 11 of the first electronic component 10 and the electrode 13 of the second electronic component 12 via the conductive particle aggregate 5 constituting the arrangement element 6, and there is no conductive particle aggregate 5 between adjacent electrodes to the extent that it would cause a short circuit. Example

[0093] <First Embodiment> The following describes embodiments of the present technology. In the first embodiment, an anisotropic conductive film is used as an adhesive layer of a conductive adhesive film to fabricate a connector, and various conduction characteristics (conductivity resistance between connecting electrodes and insulation resistance between adjacent electrodes) are measured and evaluated in cases where there is no alignment misalignment between the anisotropic conductive film and the evaluation substrate and in cases where alignment misalignment occurs.

[0094] [Construction of the connector] like Figure 20 As shown, a connector 40 is fabricated by thermocompressing an anisotropic conductive film 4 onto a camera module evaluation substrate 10 (ceramic substrate, 6.0 mm wide, 1.0 mm wide mounting surface for terminal blocks, 200 μm wide electrode, 500 μm long electrode, line:gap ratio 1:1, terminal thickness 10 μm, Ni (substrate) / Au (surface) plating, having a cavity structure, with terminal blocks on two opposing sides) and an FPC 12 (polyimide film, 400 μm pitch, line:gap ratio 1:1, terminal thickness 12 μm, Ni (substrate) / Au (surface) plating). A tool 42 is pressed down from the FPC side through a 200 μm thick silicone rubber 41, and thermocompressing is performed at a temperature of 130°C, a pressure of 1 MPa, and a time of 6 seconds.

[0095] Figure 20 (A) is a perspective view showing the evaluation substrate 10. Figure 20 (B) is a perspective view showing the state in which the anisotropic conductive film 4 is attached to the electrode 11 of the evaluation substrate 10. Figure 20 (C) is a perspective view showing the state in which the FPC 12 is disposed on an evaluation substrate 10 to which the anisotropic conductive film 4 is attached. Figure 20 (D) is a perspective view showing the process of pressing the FPC 12 onto the silicone rubber 41 using a crimping tool 42. Figure 20 (E) is a perspective view of a connector sample 40 in which the FPC 12 is connected to the evaluation substrate 10 via an anisotropic conductive film 4.

[0096] Evaluation of conduction characteristics The on-resistance between the connecting electrodes and the insulation resistance between adjacent electrodes of the connector were measured using a digital multimeter (manufactured by Yokogawa Electric Corporation) via a 4-terminal method when a current of 1 mA was flowing through it. Measurements were performed on connectors initially connected and on connectors after a reliability evaluation test at 121°C, 100% humidity, 2 atm pressure, and 24 hours. The on-resistance of 10 connector samples (N=10) was measured, and the sample with the highest resistance value was used for evaluation.

[0097] <Example 1> Fabrication of anisotropic conductive films Prepare 5 parts by weight of resin core conductive particles (Ni (substrate) / Au (surface) plating, resin core) with an average particle size of 20 μm and 95 parts by weight of an insulating adhesive composed of the following components. Add the insulating adhesive to a planetary mixer (product name: Awatori Rentaro, manufactured by THINKY) and stir for 1 minute to prepare an adhesive composition. Then, apply the adhesive composition to a 50 μm thick PET film and dry it in an oven at 80°C for 5 minutes to form an adhesive layer composed of the adhesive composition on the PET film, creating an insulating adhesive layer with a width of 6.0 mm and a thickness of 25 μm. In this insulating adhesive layer, densely aggregate conductive particles are arranged using a metal mask having an opening pattern corresponding to the electrode pattern formed on the evaluation substrate 10, forming an arrangement element composed of conductive particle aggregates with an average particle size of 80 μm. In Example 1, an anisotropic conductive film is used, in which arrangement elements 6 of the same shape as the electrodes 11 formed on the evaluation substrate 10 are arranged corresponding to the electrode pattern on the evaluation substrate 10.

[0098] The insulating adhesive is a mixture of ethyl acetate and toluene, which contains, in a solid composition of 50% by mass, 47 parts by mass of phenoxy resin (trade name: YP-50, manufactured by Shin-Nippon Chemical Epoxy Resin Manufacturing Co., Ltd.), 3 parts by mass of monofunctional monomer (trade name: M-5300, manufactured by Toa Synthetic Co., Ltd.), 25 parts by mass of polyurethane resin (trade name: UR-1400, manufactured by Toyobo Co., Ltd.), 15 parts by mass of rubber component (trade name: SG80H, manufactured by Nagase ChemteX Co., Ltd.), 2 parts by mass of silane coupling agent (trade name: A-187, manufactured by Momentive Performance Materials Japan), and 3 parts by mass of organic peroxide (trade name: Nyper BW, manufactured by Nippon Oil Co., Ltd.).

[0099] <Example 2> In Example 2, as Figure 6As shown in (A), the arrangement element 6 is formed and arranged such that a conductive particle aggregate (average particle size 80 μm) is disposed at the center of the electrode 11 formed on the evaluation substrate 10. Otherwise, an anisotropic conductive film is fabricated under the same conditions as in Example 1.

[0100] <Example 3> In Example 3, as Example 4 As shown in (A), the arrangement element 6 is formed and arranged in such a way that two conductive particle aggregates (average particle size 80 μm) are arranged side by side with respect to the electrode 11 formed on the evaluation substrate 10 along the electrode length direction at the center of the electrode width. Otherwise, an anisotropic conductive film is made under the same conditions as in Example 1.

[0101] <Comparative Example 1> In Comparative Example 1, 5 parts by mass of resin core conductive particles (Ni (substrate) / Au (surface) coating, resin core) with an average particle size of 20 μm and 95 parts by mass of an insulating adhesive composed of the following components were added to a planetary mixing apparatus (product name: Rotation-Revolution Vacuum Mixer (Awatori Rentaro), manufactured by THINKY Corporation) and stirred for 1 minute to prepare an anisotropic conductive adhesive composition. Furthermore, the anisotropic conductive adhesive composition was applied to a 50 μm thick PET film and dried in an oven at 80°C for 5 minutes, forming an adhesive layer composed of the anisotropic conductive adhesive composition on the PET film to produce a dispersed anisotropic conductive film with a width of 6.0 mm and a thickness of 25 μm. The conductive particles had a particle density of 300 particles / mm². 2 The method of application is the same as in Example 1. The insulating adhesive is the same.

[0102] <Comparative Example 2> In Comparative Example 2, a resin plate with recesses arranged in a hexagonal lattice was fabricated. Conductive particles (average particle size 20 μm) were filled into these recesses, and the conductive particles were transferred to an insulating adhesive layer fabricated in the same manner as in Example 1. This resulted in an anisotropic conductive film with conductive particles arranged in a neat hexagonal lattice pattern covering the entire surface. The conductive particles were neatly arranged at a particle density of 600 particles / mm².

[0103] <Comparative Example 3> In Comparative Example 3, an anisotropic conductive film was prepared by means of the same method as in Example 1, in which an aggregate of conductive particles with an average particle size of 20 μm (average particle size of 80 μm) arranged in a hexagonal lattice pattern was formed on the entire surface of the insulating adhesive layer.

[0104] [Initial Connection] First, the evaluation results of the conductivity characteristics in the initial stage of connection after the connector has just been manufactured are explained.

[0105] Insulation resistance between adjacent electrodes (without offset) Table 1 Table 1 shows the results of determining whether short circuits occurred between adjacent electrodes when the gap between adjacent electrodes was set to 20 μm, 40 μm, 90 μm, and 200 μm. No alignment misalignment occurred between the anisotropic conductive film and the adjacent electrodes of the evaluation substrate 10. The insulation resistance was set to 10... 8 Ω and above are set to ○ (no short circuit), which will result in less than 10 8 Ω is set to × (short circuit).

[0106] As shown in Table 1, the connectors described in Examples 1 to 3 can arrange the arrangement elements on the electrodes 11 of the evaluation substrate 10 without causing short circuits between adjacent electrodes, regardless of the width of the gap between adjacent electrodes. On the other hand, in Comparative Example 1, which is composed of an anisotropic conductive film made of an anisotropic conductive adhesive composition in which conductive particles are dispersed throughout the entire surface, the gap between adjacent electrodes is 40 μm or less, resulting in a short circuit. Furthermore, in Comparative Example 2, where conductive particles are arranged in a high-density, orderly manner throughout the entire surface of the adhesive layer as an anisotropic conductive film, the gap between adjacent electrodes is 20 μm or less than the particle size, resulting in a short circuit. Moreover, in Comparative Example 3, where conductive particle aggregates are arranged in an orderly manner throughout the entire surface of the adhesive layer, if the gap between adjacent electrodes is 40 μm or less, which is smaller than the diameter of the conductive particle aggregates, a short circuit occurs.

[0107] [Conductivity between connecting electrodes] Table 2 Table 2 shows the results of measuring the on-resistance between the connecting electrodes in the connector formed due to alignment misalignment between the electrodes of the anisotropic conductive film and the evaluation substrate. On-resistance of 50 mΩ or less is ○○ (Excellent), 50 mΩ or more but less than 100 mΩ is ○ (Good), 100 mΩ or more but less than 120 mΩ is △ (Pass), and more than 120 mΩ is × (Poor). Furthermore, in Comparative Examples 1 to 3, conductive particles or conductive particle aggregates are dispersed or neatly arranged on the entire surface of the adhesive layer. Therefore, it is not necessary to align the arrangement elements with the positions of the electrodes on the evaluation substrate as in Examples 1 to 3, and thus no alignment misalignment occurs. Therefore, these examples serve as reference examples.

[0108] As shown in Table 2, in Example 1, if the arrangement element formed with a width of 200 μm is offset to 200 μm, the conductive particle aggregates are not captured, resulting in poor conductivity. In Example 2, if the offset from the center of the 200 μm wide electrode in the width direction is reduced to 100 μm, only about half of the conductive particle aggregates are captured, and the conduction resistance becomes high. If the offset is reduced to 120 μm, the conductive particle aggregates are not captured, resulting in poor conductivity. In Example 3, the arrangement element is configured with two conductive particle aggregates for each electrode, thus ensuring conductivity up to a offset of 120 μm. However, if the offset is reduced to 140 μm, the conductive particle aggregates are not captured, resulting in poor conductivity.

[0109] Insulation resistance between adjacent electrodes (with offset) Table 3 Table 3 shows the results of measuring the insulation resistance between adjacent electrodes in the connector formed by the alignment misalignment between the electrodes of the anisotropic conductive film and the evaluation substrate. An insulation resistance of 10... 8 Ω and above are set to ○ (no short circuit), which will result in less than 10 8 Ω is set to × (short circuit). In addition, in Comparative Examples 1 to 3, conductive particles or conductive particle aggregates are dispersed or neatly arranged on the entire surface of the adhesive layer. Therefore, it is not necessary to align the arrangement elements and the position of the electrodes of the evaluation substrate as in Examples 1 to 3, and thus no alignment misalignment occurs. Therefore, they are meant as reference examples.

[0110] As shown in Table 3, if the arrangement element formed with a width of 200 μm in Example 1 shifts to 200 μm, the same width as the gap between adjacent electrodes, a short circuit occurs. In Examples 2 and 3, even if the shift reaches 200 μm, no short circuit occurs.

[0111] Reliability Testing Next, the evaluation results of the conductivity characteristics of the connector after the reliability test will be explained. The reliability test conditions were set as follows: temperature 121℃, humidity 100%, air pressure 2 atm, 24h. Similar to the initial connection, the conduction resistance between the connecting electrodes and the insulation resistance between adjacent electrodes in the connector were measured. All evaluation criteria were the same as those in the initial connection.

[0112] Insulation resistance between adjacent electrodes (without offset) Table 4 Table 4 shows the results of determining whether short circuits occurred between adjacent electrodes when the gap between adjacent electrodes was set to 20 μm, 40 μm, 90 μm, and 200 μm. No alignment misalignment occurred between the anisotropic conductive film and the adjacent electrodes of the evaluation substrate.

[0113] As shown in Table 4, the connectors described in Examples 1 to 3 can arrange the arrangement elements on the electrodes of the evaluation substrate, and after reliability testing, no short circuit occurs regardless of the width of the gap between adjacent electrodes. On the other hand, the connectors described in Comparative Examples 1 to 3 experienced short circuits in the same manner as in the initial connection stage. Furthermore, in Comparative Example 3, where conductive particle aggregates were neatly arranged on the entire surface of the adhesive layer, short circuits occurred even when the gap between adjacent electrodes was 90 μm larger than the diameter of the conductive particle aggregates, and the insulation between adjacent electrodes deteriorated after reliability testing.

[0114] [Conductivity between connecting electrodes] Table 5 Table 5 shows the results of measuring the on-resistance between the connecting electrodes in the connector formed by the alignment misalignment between the electrodes of the anisotropic conductive film and the evaluation substrate. Furthermore, in Table 5, Comparative Examples 1 to 3 are also referred to as examples.

[0115] As shown in Table 5, in Example 1, similar to the initial connection stage, conductive particle aggregates were captured within an offset of less than 200 μm for the arrangement elements formed with a width of 200 μm. However, if an offset of up to 200 μm occurred, the conductive particle aggregates were not captured, resulting in poor conductivity. In Example 2, conductive particle aggregates were captured within an offset of less than 100 μm from the center of the 200 μm wide electrode in the width direction. However, if an offset of more than 100 μm occurred, the conductive particle aggregates were not captured, resulting in poor conductivity. In Example 3, conductive particle aggregates were captured within an offset of less than 120 μm. However, if an offset of more than 120 μm occurred, the conductive particle aggregates were not captured, resulting in poor conductivity.

[0116] Insulation resistance between adjacent electrodes (with offset) Table 6 Table 6 shows the results of measuring the insulation resistance between adjacent electrodes in a connector formed by the alignment misalignment between the anisotropic conductive film and the electrodes of the evaluation substrate. Furthermore, Comparative Examples 1 to 3 are also referred to as examples in Table 6.

[0117] As shown in Table 6, in Example 1, the arrangement elements formed with a width of 200 μm do not short-circuit up to an offset of less than 140 μm, but short-circuit occurs if the offset reaches 180 μm. In Examples 2 and 3, short-circuit does not occur even if the offset reaches 200 μm.

[0118] <Second Embodiment> Next, the second embodiment will be described. In the second embodiment, an anisotropic conductive film with different amounts of conductive particles is fabricated. A connector sample 40 is fabricated using this anisotropic conductive film to connect the FPC 12 to the evaluation substrate 10. The conductivity performance (conduction resistance between connecting electrodes, insulation resistance between adjacent electrodes) is measured and evaluated. The evaluation substrate 10 and FPC 12 are the same as in the first embodiment.

[0119] The continuity resistance between the connecting electrodes was measured during the initial connection phase and after the reliability test. The conditions for the reliability test were the same as in the first embodiment. Furthermore, the method for measuring the continuity resistance between the connecting electrodes and the evaluation criteria were the same as in the first embodiment. The insulation resistance between adjacent electrodes was measured to check for short circuits between adjacent electrodes when the gap between adjacent electrodes was set to 20 μm, 40 μm, and 80 μm. Furthermore, the method for measuring the insulation resistance between adjacent electrodes and the evaluation criteria were the same as in the first embodiment.

[0120] <Example 4> In Example 4, the same anisotropic conductive film as in Example 1 was used to fabricate a connector sample 40 for connecting the FPC 12 to the evaluation substrate 10. There was no positional misalignment between the arrangement element 6 and the electrode 11. The bonding process was performed with the tool's thermal pressure conditions set to 130°C, 2 MPa, and 6 seconds, otherwise identical to Example 1.

[0121] <Example 5> In Example 5, solder particles with an average particle size of 20 μm were used as conductive particles, and otherwise, connector sample 40 was prepared under the same conditions as in Example 4.

[0122] <Comparative Example 4> In Comparative Example 4, the particle density of the conductive particles was 150 particles / mm². 2 In addition, the same anisotropic conductive film as in Comparative Example 1 was used to fabricate the connector sample 40. The bonding process was performed with the tool's heat pressure conditions set to 130°C, 2 MPa, and 6 seconds, otherwise the same as in the first embodiment.

[0123] <Comparative Example 5> In Comparative Example 5, the same anisotropic conductive film as in Comparative Example 1 was used to fabricate the connector sample 40. The bonding process was performed with the tool's heat pressure conditions set to 130°C, 2 MPa, and 6 seconds, otherwise identical to the first embodiment.

[0124] <Comparative Example 6> In Comparative Example 6, the particle density of the conductive particles was 600 particles / mm². 2 In addition, the same anisotropic conductive film as Comparative Example 1 was used to fabricate the connector sample 40. The bonding process was performed with the tool's heat pressure conditions set to 130°C, 2 MPa, and 6 seconds, otherwise the same as in the first embodiment.

[0125] <Comparative Example 7> In Comparative Example 7, the same anisotropic conductive film as in Comparative Example 2 was used to fabricate the connector sample 40. The bonding process was the same as in the first embodiment, except that the tool's heat pressure conditions were set to 130°C, 2 MPa, and 6 seconds.

[0126] <Comparative Example 8> In Comparative Example 8, solder particles with an average particle size of 20 μm were used as conductive particles, with a particle density of 150 particles / mm. 2 In addition, the same anisotropic conductive film as in Comparative Example 1 was used to fabricate the connector sample 40. The bonding process was performed with the tool's heat pressure conditions set to 130°C, 2 MPa, and 6 seconds, otherwise the same as in the first embodiment.

[0127] <Comparative Example 9> In Comparative Example 9, the particle density was 300 particles / mm². 2 In addition, the same anisotropic conductive film as in Comparative Example 8 was used to fabricate the connector sample 40. The bonding process was performed with the tool's heat pressure conditions set to 130°C, 2 MPa, and 6 seconds, otherwise the same as in the first embodiment.

[0128] <Comparative Example 10> In Comparative Example 10, the particle density was 600 particles / mm². 2 In addition, the same anisotropic conductive film as in Comparative Example 8 was used to fabricate the connector sample 40. The bonding process was performed with the tool's heat pressure conditions set to 130°C, 2 MPa, and 6 seconds, otherwise the same as in the first embodiment.

[0129] Table 7 Example 5 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Comparative Example 8 Comparative Example 9 Comparative Example 10 Conductive particle aggregate Same shape as electrode Same shape as electrode Conductive particle (20 μm) - - - - - - - Resin core Ni / Au plating layer Solder particle Resin core Ni / Au plating layer Resin core Ni / Au plating layer Resin core Ni / Au plating layer Resin core Ni / Au plating layer Solder particle Solder particle Solder particle Particle arrangement Dispersion - - Dispersion Dispersion Arrangement in order Dispersion Dispersion Dispersion On-resistance (at the initial connection) Particle density (pieces / mm 2 ) - - 150 300 600 600 150 300 600 On-resistance (after reliability test) ○ ○○ △ ○ ○ ○ ○ ○ ○○ Insulation resistance (gap 20 μm) △ ○○ × × × × △ ○ ○○ Insulation resistance (gap 40 μm) ○ ○ × × × × × × × Insulation resistance (gap 80 μm) ○ ○ ○ × × ○ ○ × × Example 4 ○ ○ ○ ○ × ○ ○ ○ × As shown in Table 7, in Example 4, the arrangement elements were formed with a width equal to the electrode width, and therefore the evaluation of the conduction resistance between the connecting electrodes in the initial connection phase was ○ (Good). However, after the reliability test, the evaluation of the conduction resistance between the connecting electrodes became △ (Pass). This is a phenomenon caused by the rebound of the resin core of the conductive particles. In Example 5, where solder particles were used to form the arrangement elements with a width equal to the electrode width, the evaluation of the conduction resistance between the connecting electrodes in both the initial connection phase and after the reliability test was ○○ (Excellent). Therefore, it can be seen that the anisotropic conductive film using solder particles as conductive particles also exhibits excellent conductivity in both the initial connection phase and after the reliability test.

[0130] On the other hand, in Comparative Examples 4 to 10, the evaluation of the conduction resistance between the connecting electrodes in the initial connection stage was ○○ (excellent), ○ (good), or △ (passable), but after the reliability test, except for Comparative Examples 8 to 10 which used solder particles, it became × (poor).

[0131] Furthermore, in Examples 4 and 5, the arrangement elements can be placed on the electrodes of the evaluation substrate, regardless of the width of the gap between adjacent electrodes, and the evaluation of the insulation resistance between adjacent electrodes is ○ (no short circuit).

[0132] On the other hand, in Comparative Examples 4 to 10, the evaluation of the insulation resistance between adjacent electrodes deteriorated as the gap between adjacent electrodes narrowed. In the case where the gap between adjacent electrodes was 20 μm, it became × (short circuit) in all samples.

[0133] <Third Embodiment> Next, the third embodiment will be described. In the third embodiment, an anisotropic conductive film used in the second embodiment is used to fabricate a connector sample 40 that connects the FPC 12 to the evaluation substrate 10, and the conductivity performance (conduction resistance between connecting electrodes and insulation resistance between adjacent electrodes) is measured and evaluated. The dimensions of each electrode of the evaluation substrate 10 and the FPC 12 are 150 μm in width and 100 μm in length. That is, in the third embodiment, compared with the second embodiment, the evaluation substrate 10 and the FPC 12 with smaller electrode dimensions are used.

[0134] The continuity resistance between the connecting electrodes was measured during the initial connection phase and after the reliability test. The conditions for the reliability test were the same as in the first embodiment. Furthermore, the method for measuring the continuity resistance between the connecting electrodes and the evaluation criteria were the same as in the first embodiment. The insulation resistance between adjacent electrodes was measured to check for short circuits between adjacent electrodes when the gap between adjacent electrodes was set to 20 μm, 40 μm, and 80 μm. Furthermore, the method for measuring the insulation resistance between adjacent electrodes and the evaluation criteria were the same as in the first embodiment.

[0135] Table 8 Example 5 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Comparative Example 8 Comparative Example 9 Comparative Example 10 Conductive particle aggregate Same shape as electrode Same shape as electrode Conductive particle (20 μm) - - - - - - - Resin core Ni / Au plating layer Solder particle Resin core Ni / Au plating layer Resin core Ni / Au plating layer Resin core Ni / Au plating layer Resin core Ni / Au plating layer Solder particle Solder particle Solder particle Particle arrangement Dispersion - - Dispersion Dispersion Arrangement in order Dispersion Dispersion Dispersion On-resistance (at the initial connection) Particle density (pieces / mm 2 )]> - - 150 300 600 600 150 300 600 On-resistance (after reliability test) ○ ○○ △ △ △ △ △ ○ ○○ Insulation resistance (gap 20 μm) × ○○ × × × × × ○ ○○ Insulation resistance (gap 40 μm) ○ ○ × × × × × × × Insulation resistance (gap 80 μm) ○ ○ ○ × × ○ ○ × × ​ ○ ○ ○ ○ × ○ ○ ○ × As shown in Table 8, it can be seen that the evaluation of the conduction resistance between the connecting electrodes in Examples 4 and 5 after the initial connection and reliability test is the same as that in Example 2 (Table 7), and the conduction performance is stable even when the electrode size is further reduced.

[0136] On the other hand, in Comparative Examples 4 to 10, except for Comparative Examples 9 and 10, the evaluation of the conduction resistance between the connecting electrodes in the initial connection stage was △ (pass), and after the reliability test it was × (fail).

[0137] Furthermore, in Examples 4 and 5, the arrangement elements can be placed on the electrodes of the evaluation substrate, regardless of the width of the gap between adjacent electrodes, and the evaluation of the insulation resistance between adjacent electrodes is ○ (no short circuit).

[0138] On the other hand, in Comparative Examples 4 to 10, the evaluation of the insulation resistance between adjacent electrodes deteriorated as the gap between adjacent electrodes narrowed. In the case where the gap between adjacent electrodes was 20 μm, it became × (short circuit) in all samples.

[0139] Symbol Explanation 1 Conductive adhesive film, 2 Substrate, 3 Conductive particles, 4 Adhesive layer, 5 Conductive particle aggregate, 6 Arrangement element, 8 Monolith, 10 First electronic component, 11 Electrode, 12 Second electronic component, 21 First terminal row, 22 Second terminal row, 23 Third terminal row, 30 Film roll, 31 Core, 33 Mask, 34 Opening, 40 Connector, 41 Cushioning material, 42 Crimping tool.

Claims

1. A conductive adhesive film, comprising: Substrate; and An adhesive material layer, disposed on one side of the substrate, contains conductive particles. In the conductive adhesive film, The conductive particles contained in the adhesive material layer constitute a particle agglomerate formed by condensing multiple conductive particles. The adhesive material layer is arranged with arrangement elements composed of particle aggregates in a predetermined pattern corresponding to the electrode arrangement of the electronic component to which the conductive adhesive film is attached.

2. The conductive adhesive film according to claim 1, wherein, The arrangement elements constituting the arrangement pattern are composed of one or more of the particle condensates.

3. The conductive adhesive film according to claim 1, wherein, The arrangement elements constituting the arrangement pattern are composed of multiple particle condensates. The arrangement elements are aggregated, dispersed, or neatly arranged into multiple particle condensates.

4. The conductive adhesive film according to any one of claims 1 to 3, wherein, The area of ​​the arrangement element is less than or equal to the area of ​​the electrodes constituting the electrode arrangement.

5. The conductive adhesive film according to any one of claims 1 to 3, wherein, When the arrangement direction of the arrangement element in the arrangement pattern is set to the width direction of the arrangement element, and the arrangement direction of the electrode in the electrode arrangement is set to the width direction of the electrode, the width of the arrangement element is more than 40% and less than 100% of the width of the electrode.

6. A method for manufacturing a conductive adhesive film, the conductive adhesive film having a substrate and an adhesive material layer disposed on one side of the substrate and containing conductive particles. The method for manufacturing the conductive adhesive film includes an arrangement step of arranging arrangement elements, which are composed of particle aggregates formed by agglomerating multiple conductive particles, in a predetermined arrangement pattern corresponding to the electrode arrangement of the electronic component to which the conductive adhesive film is attached, on the adhesive material layer. The arrangement process involves placing the conductive particles onto the adhesive material layer via a mask having predetermined openings.

7. The method for manufacturing the conductive adhesive film according to claim 6, wherein, The arrangement process uses a metal mask or rotating wire mesh as the mask to place the conductive particles on the adhesive material layer.

8. The method for manufacturing the conductive adhesive film according to claim 6 or 7, wherein, The opening diameter of the opening in the mask is more than 200% of the average particle size of the conductive particles.

9. A connector that connects a first electronic component and a second electronic component via a cured film of an adhesive layer containing a plurality of conductive particles of a conductive adhesive film. The conductive adhesive film has the following characteristics: Substrate; and An adhesive material layer, disposed on one side of the substrate, contains conductive particles. The conductive particles contained in the adhesive material layer constitute a particle agglomerate formed by condensing multiple conductive particles. The adhesive material layer is arranged with arrangement elements composed of particle aggregates in a predetermined pattern corresponding to the electrode arrangement of the first electronic component to which the conductive adhesive film is attached.

10. A method for manufacturing a connector, comprising: The process of attaching a conductive adhesive film containing multiple conductive particles to a first electronic component; and The connection process of connecting the first electronic component and the second electronic component via the conductive adhesive film. The conductive adhesive film: It has a substrate and an adhesive material layer disposed on one side of the substrate and containing conductive particles. The conductive particles contained in the adhesive material layer constitute a particle agglomerate formed by condensing multiple conductive particles. The adhesive material layer has arrangement elements composed of particle aggregates arranged in a predetermined pattern corresponding to the electrode arrangement of the first electronic component to which the conductive adhesive film is attached. In the configuration process, the electrodes of the first electronic component are aligned with the arrangement elements, and the conductive adhesive film is attached to the first electronic component.

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