Method for manufacturing a connection structure, connection film, method for manufacturing a connection film

Abstract

The present disclosure provides a manufacturing method of a connection structure that can mount electronic components at high density using a connection film in which an adhesive layer is accompanied by insufficient printing (bleeding). In the manufacturing method of the connection structure, the connection structure is formed by connecting a first terminal (5) of a first electronic component (3) and a second terminal (6) of a second electronic component (4) through a cured film (11A) that is cured from an adhesive layer (11) of a connection film (2), and the manufacturing method of the connection structure includes: a sticking step of sticking the adhesive layer (11) of the connection film (2) to the first electronic component (3); a placement step of placing the second terminal (6) on the first terminal (5) with the adhesive layer (11) interposed therebetween; and a connection step of pressing the second electronic component (4) to cure the adhesive layer (11), the adhesive layer (11) having: a main body portion (12) having a prescribed thickness; and tapered inclined portions (13) formed on both width direction sides of the main body portion (12), and in the sticking step, the main body portion (12) is stuck while being aligned with the first terminal (5) in the width direction of the adhesive layer (11).

Description

Technical Field

[0001] This technology relates to a method for manufacturing a connecting film for connecting electronic components. This application claims priority based on Japanese Patent Application No. 2024-052333, filed on March 27, 2024, which is incorporated herein by reference. Background Technology

[0002] In recent years, the density of components has been continuously increasing in devices beyond smartphones, including portable terminals and display devices. Therefore, while miniaturizing components is a driving force for this trend, it also creates limitations due to the shrinking of installation space. For example, in camera modules, the increasing size and multi-view capabilities of cameras (capturing units, image sensors) necessitate ensuring sufficient installation space.

[0003] Figure 26 This is a perspective view schematically representing an example of a substrate for a camera module. Figure 26 (A) is a perspective view schematically showing an example of a substrate having a recess (cavity) on the mounting surface. Figure 26 (B) is a perspective view schematically representing an example of a substrate with a polygonal mounting surface. For example... Figure 26 (A) and Figure 26 As shown in (B), efforts were made to remove unnecessary parts in order to ensure space, such as omitting the substrate, the corner 101 of the FPC (Flexible Printed Circuits), and providing a recess 102 on the mounting surface.

[0004] Such complex-shaped substrates are difficult to mount using conventional bonding films. Methods for mounting complex-shaped substrates, such as applying conductive paste using a dispensing machine, struggle to achieve precise positioning, control of overflow, and uniform thickness, leading to unstable conductive connections. Furthermore, the dispensing process is excessively time-consuming, negatively impacting yield, making it a challenging undertaking.

[0005] Patent Document 1 discloses a method for partially cutting the support membrane and removing the unwanted connecting membrane portion to monolithize the connecting membrane. However, the technology described in Patent Document 1 increases material consumption and the number of processes, leaving room for improvement in the productivity of the connecting membrane.

[0006] Furthermore, the need for further space saving necessitates improvements in processing methods that can accommodate finer linewidths. When the film is cut into thinner widths, there is a manufacturing bottleneck that makes it difficult to achieve long dimensions, such as the conductive adhesive layer lifting off the support film. In previous processing methods, if the width is set to less than 0.5 mm, there are concerns about reduced productivity when scaling up to longer dimensions.

[0007] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2020-198422 Summary of the Invention

[0008] The problem that the invention aims to solve A method for slitting the support film after printing the conductive adhesive onto it in a narrow width was investigated. This manufacturing method has the following drawback: towards the ends of the narrowly printed conductive adhesive, the thickness gradually decreases in a tapered shape due to underprinting (skimming), making it difficult to achieve uniformity. Underprinting (skimming) can also be referred to as insufficient resin at the ends.

[0009] In addition, electronic components generally have multiple terminals arranged in a certain way, and there are gaps such as spaces between terminals (between bumps) in the arrangement direction. Therefore, when the connecting film is used for connecting electronic components, it is required to design the resin filling action.

[0010] Therefore, the purpose of this technology is to provide a method for manufacturing a connecting structure that enables high-density mounting of electronic components using a connecting film with an adhesive layer that has underprinting (skimming), and a connecting film and a method for manufacturing the same that can be processed even when conductive adhesive is printed in a narrower width.

[0011] Solution for solving the problem To solve the aforementioned technical problems, the manufacturing method of the connecting structure of this technology comprises a connecting structure formed by connecting a first terminal of a first electronic component having a first terminal and a second terminal of a second electronic component having a second terminal through a curing film. The curing film is formed by curing an adhesive layer of the connecting film. The manufacturing method of the connecting structure includes: a pasting step, in which the adhesive layer of the connecting film is pasted onto the first electronic component; a positioning step, in which the second terminal is placed on the first terminal through the adhesive layer; and a connecting step, in which the second electronic component is pressed to cure the adhesive layer. The adhesive layer has: a main body portion having a predetermined thickness; and tapered inclined portions formed on both ends of the main body portion in the width direction. In the pasting step, the main body portion is aligned with the first terminal in the width direction of the adhesive layer for pasting.

[0012] Furthermore, the connecting film of this technology has: a release film; and an adhesive layer, which is stacked along the longitudinal direction of the release film. The adhesive layer has: a main body portion having a specified thickness; and a tapered inclined portion formed at both ends of the main body portion in the width direction. The ratio of the width of the inclined portion to the width of the adhesive layer is 5% to 20%.

[0013] Furthermore, the manufacturing method of the bonding film of this technology includes: an adhesive layer forming step, wherein an adhesive is applied to a release film in a predetermined shape, and a plurality of adhesive layers are formed on the release film in a stripe pattern; and a slitting step, wherein the release film is slit according to the adhesive layers with a predetermined width, the adhesive layers being cut in such a way that a main body portion having a predetermined thickness and tapered inclined portions formed on both ends of the main body portion in the width direction are formed, the ratio of the width of the inclined portions to the width of the adhesive layers being 5% to 20%.

[0014] Invention Effects According to this technology, electronic components can be mounted on the adhesive layer with high density using a bonding film with slanted portions (white spots). Attached Figure Description

[0015] Figure 1 This diagram illustrates the manufacturing steps of the connection structure 1 using this technology. Figure 1 (A) and Figure 1 (B) is a cross-sectional view representing the pasting step. Figure 1 (C) is a cross-sectional view representing the configuration steps.

[0016] Figure 2 It is a cross-sectional view that schematically represents the connection steps.

[0017] Figure 3 This is a cross-sectional view representing the connection structure 1.

[0018] Figure 4 (A) is a cross-sectional view showing the alignment of the connecting film with the independently set first terminal during the pasting step. Figure 4 (B) is a cross-sectional view showing the state where the adhesive layer is pasted.

[0019] Figure 5 This is a cross-sectional view showing the connection step in the manufacturing process of the connection structure shown for comparison.

[0020] Figure 6 Through Figure 5 A cross-sectional view of the connecting structure manufactured using the manufacturing steps shown.

[0021] Figure 7 This is a cross-sectional view showing an example of a connecting membrane using this technology.

[0022] Figure 8 This is a cross-sectional view showing an example of a connecting membrane with an inclined portion only on one side of the adhesive layer.

[0023] Figure 9 This is a cross-sectional view showing an example of a connecting membrane with a cross-section obtained by cutting along the thickness direction of the adhesive layer at the end of the inclined portion.

[0024] Figure 10 This is a cross-sectional view showing an example of an adhesive layer constructed by stacking a conductive adhesive layer and an insulating adhesive layer. Figure 10 (A) represents an example of a coating structure in which the two sides of the lower insulating adhesive layer are covered by an upper conductive adhesive layer. Figure 10 (B) represents an example of a coating structure in which the two sides of the lower conductive adhesive layer are covered by an upper insulating adhesive layer. Figure 10 (C) represents an example of a laminated structure where the upper layer is a conductive adhesive layer and the lower layer is an insulating adhesive layer. Figure 10 (D) represents an example of a stacked structure where the upper layer is a conductive adhesive layer and the lower layer is an insulating adhesive layer.

[0025] Figure 11 This is a diagram showing the manufacturing steps of the connecting membrane. Figure 11 (A) is a three-dimensional diagram showing the adhesive application steps. Figure 11 (B) is a three-dimensional diagram showing the state in which multiple adhesive layers are formed in a stripe pattern on the release film. Figure 11 (C) is a perspective view showing the steps of cutting the release film to a specified width according to the adhesive layer.

[0026] Figure 12 This is a side view illustrating an example of the step of applying adhesive to the release film 10.

[0027] Figure 13 This is a three-dimensional diagram representing a roll of membrane.

[0028] Figure 14 This is a cross-sectional view showing an example of another layered configuration of conductive adhesive layer and insulating adhesive layer.

[0029] Figure 15 It is used for Figure 14 The top view illustrating an example of the fabrication of the connecting membrane is shown.

[0030] Figure 16 This is a diagram illustrating an example of a method for manufacturing a connecting membrane.

[0031] Figure 17 This is a cross-sectional view showing a deformed example of the adhesive layer.

[0032] Figure 18 This is a cross-sectional view showing the following adhesive layer: the conductive adhesive layer is stacked to the left of the insulating adhesive layer in the width direction, thereby providing a single-layer region of the insulating adhesive layer without a conductive adhesive layer on the right side of the conductive adhesive layer, and the left end of the conductive adhesive layer is set to be approximately flush with the left end of the release film and the insulating adhesive layer.

[0033] Figure 19 This is a cross-sectional view showing the following adhesive layer: the insulating adhesive layer is stacked to the left of the conductive adhesive layer in the width direction, thereby providing a single-layer region of the conductive adhesive layer without an insulating adhesive layer on the right side of the insulating adhesive layer, and the left end of the insulating adhesive layer is set to be approximately flush with the left end of the release film and the conductive adhesive layer.

[0034] Figure 20 This is a cross-sectional view of the adhesive layer after the ends of the insulating adhesive layer formed on the release film in the width direction have been removed.

[0035] Figure 21 This is a cross-sectional view of the adhesive layer after the ends of the conductive adhesive layer formed on the release film in the width direction have been removed.

[0036] Figure 22 This is a diagram showing the connecting membrane A with a smaller width at the inclined section. Figure 22 (A) is a cross-sectional view showing the state after the adhesive layer has been formed. Figure 22 (B) represents the cross-sectional view obtained by cutting one side along the thickness direction, the cross-sectional view of the connecting membrane with the other side set as an inclined part, and the top view showing the dimensional relationship.

[0037] Figure 23 This is a diagram showing the connecting membrane B with a large inclined section. Figure 22 (A) is a cross-sectional view showing the state after the adhesive layer has been formed. Figure 22 (B) represents the cross-sectional view obtained by cutting one side along the thickness direction, the cross-sectional view of the connecting membrane with the other side set as an inclined part, and the top view showing the dimensional relationship.

[0038] Figure 24 This is a perspective view showing the step of applying a film-like adhesive layer to a terminal row consisting of multiple terminals arranged along the side edge near the side edge of an evaluation substrate.

[0039] Figure 25(A) is a cross-sectional view showing the pasting steps of Example 1. Figure 25 (B) is a cross-sectional view showing the pasting steps of Example 2. Figure 25 (C) is a cross-sectional view showing the pasting steps of Example 3. Figure 25 (D) is a cross-sectional view showing the pasting steps of Comparative Example 1. Figure 25 (E) is a cross-sectional view showing the pasting steps of Comparative Example 2.

[0040] Figure 26 This is a perspective view schematically representing an example of a conventional substrate. Figure 26 (A) is a perspective view schematically showing an example of a substrate having a recess (cavity) on the mounting surface. Figure 26 (B) is a perspective view schematically representing an example of a substrate with a polygonal mounting surface. Detailed Implementation

[0041] The following detailed description, with reference to the accompanying drawings, outlines the manufacturing method of the connecting structure using this technology, the connecting membrane, and the manufacturing method of the connecting membrane. It should be noted that this technology is not limited to the embodiments described below, and various modifications can be made without departing from the spirit of this technology. Furthermore, the accompanying drawings are schematic, and the proportions of various dimensions may sometimes differ from reality. Specific dimensions should be determined by referring to the following description. Additionally, the accompanying drawings also include portions where the dimensions and proportions differ from each other.

[0042] [Manufacturing method of connecting structure] In the manufacturing method of the connection structure using this technology, the connection structure is formed by connecting a first terminal of a first electronic component having a first terminal and a second terminal of a second electronic component having a second terminal through a curing film. The curing film is formed by curing an adhesive layer of the connection film. The manufacturing method of the connection structure includes: an adhesive bonding step, in which the adhesive layer of the connection film is bonded to the first electronic component; an arrangement step, in which the second terminal is arranged on the first terminal through the adhesive layer; and a connection step, in which the second electronic component is pressed to cure the adhesive layer.

[0043] The adhesive layer has tapered inclined portions at both ends in the width direction. During the bonding step, the central portion in the width direction is aligned with the center position of the first terminal.

[0044] Figure 1 and Figure 2 This diagram illustrates the manufacturing steps of the connection structure 1 using this technology. Figure 1 (A) Figure 1 (B) indicates the paste step. Figure 1 (C) indicates the configuration step. Figure 2The connection steps are illustrated schematically. Figure 3 This is a cross-sectional view representing the connection structure 1.

[0045] [First electronic component / Second electronic component] There are no particular limitations on the first electronic component 3 and the second electronic component 4, and they can be appropriately selected according to the purpose. Examples of the first electronic component 3 and the second electronic component 4 include ceramic substrates, rigid substrates, flexible printed circuits (FPC), glass substrates, plastic substrates, resin multilayer substrates, IC (Integrated Circuit) modules, IC chips, connectors, LSI (Large Scale Integration), LEDs (Light Emitting Diodes), switches, etc.

[0046] The first electronic component 3 has a first terminal 5. The first terminals 5 can be formed independently or can be arranged in a terminal array 5R. Furthermore, the location of the first terminals 5 is not particularly limited and can be appropriately designed according to the wiring pattern of the first electronic component 3; this is particularly effective when formed at the end of the substrate of the first electronic component 3 in this technology. Similarly, the second terminals 6 formed on the second electronic component 4 and connected to the first terminals 5 can also be formed independently or can be arranged in a terminal array 6R. Furthermore, the location of the second terminals 6 is not particularly limited and can be appropriately designed according to the wiring pattern of the second electronic component 4; this is particularly effective when formed at the end of the substrate of the second electronic component 4 in this technology.

[0047] It should be noted that there are no particular limitations on the connection structure used in this technology. For example, it can be used in the manufacturing methods of all electronic devices that use electrical connections, such as semiconductor devices (including all components that utilize semiconductors, such as optical components, thermoelectric conversion components, and photoelectric conversion components, 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, shooting devices (using image sensors such as camera modules), electrical installations in vehicles (mobile devices), medical devices, sensor devices (touch sensors, fingerprint authentication, iris authentication, etc.), and home appliances.

[0048] [Connecting membrane] The connecting membrane 2 has: a release film 10; and an adhesive layer 11, which is laminated on the release film 10. The adhesive layer 11 has: a main body portion 12 having a predetermined thickness; and a tapered inclined portion 13 formed on both ends of the main body portion 12 in the width direction.

[0049] There are no particular limitations on the connecting film 2, and examples include conductive films containing film-like (the shape can also be referred to as film-like / protruding / convex, hereinafter simply referred to as "film-like") conductive particles, anisotropic conductive films (ACF), and non-conductive adhesive films (NCF). They can also be multilayered with two or more layers. Furthermore, there are no particular limitations on the curing type of the connecting film 2, and examples include thermosetting types, photocuring types, and photothermal curing types. Additionally, the connecting film 2 can also be a hot-melt type using thermoplastic resin.

[0050] The specific structure of the connecting membrane 2 and the manufacturing steps of the connecting membrane 2 will be described in detail later.

[0051] [Paste steps] In the pasting step, the adhesive layer 11 of the connecting film 2 is transferred to the first electronic component 3. As described above, there are no particular limitations on the first electronic component 3 and the second electronic component 4, and they can be appropriately selected according to the purpose. In this specification, in the pasting step, the electronic component to which the connecting film 2 is pasted is designated as the first electronic component 3.

[0052] The adhesive layer 11 is transferred, for example, by using an adhesive applicator to press it onto the mounting surface of the first electronic component 3 on the worktable by pressing it from the release film 10 side of the connecting film 2. After the adhesive layer 11 is transferred, the connecting film 2 becomes a release film 10 only and is then rolled up. Multiple release films 10 can also be provided on a larger area. Except for cutting the application area during use, it can be used through the same operation.

[0053] When each of the first terminals 5 is formed independently, an adhesive layer 11, which is monolithically formed corresponding to the first terminal 5, is adhered. Furthermore, when multiple first terminals 5 constitute a terminal row 5R, an adhesive layer 11, which is formed into a film shape corresponding to the terminal row 5R, is adhered.

[0054] Figure 4 (A) is a cross-sectional view showing the alignment of the connecting film 2 and the first terminal 5 during the pasting step. Figure 4 (B) is a cross-sectional view showing the state where the adhesive layer 11 is pasted. For example... Figure 4 As shown in (A), during the bonding step, the main body 12 is aligned with the longitudinal direction 5L of the first terminal 5 along the width direction 11W of the adhesive layer 11. Preferably, the adhesive layer 11 is aligned such that the center position of the main body 12 in the width direction 11W is at the center position of the first terminal 5 in the longitudinal direction 5L. This prevents the inclined portion 13 from being located at the center of the first terminal 5, improving the reliability of conductivity and connection.

[0055] It should be noted that, as Figure 4 As shown, preferably, the inclined portion 13 is formed at a distance that does not extend from the substrate side edge 16 of the first electronic component 3. This prevents the adhesive layer 11 from overflowing onto the surface of the worktable on which the first electronic component 3 is placed, or onto the back of the worktable, causing contamination during the connection step of the second electronic component 4.

[0056] Figure 1 (A) is a cross-sectional view showing the alignment of the connecting film 2, in which a film-like adhesive layer 11 is provided on a plurality of first terminal portions 5. Figure 1 (B) is a cross-sectional view showing the state in which the adhesive layer 11 is temporarily attached to the first electronic component 3. For example... Figure 1 As shown in (A), in the bonding step, the main body 12 is aligned with the terminal row 5R of the first terminal 5 along the longitudinal direction 11L of the adhesive layer 11, and the connecting film 2 is bonded to the first electronic component 3. Preferably, the adhesive layer 11 is aligned such that the center position of the main body 12 in the longitudinal direction 11L is located at the center position of the terminal row 5R of the first terminal 5 in the arrangement direction 5RL.

[0057] In addition, during the pasting process, the connecting film 2 can be pasted onto multiple terminal rows 5R multiple times, or the connecting film 2 can be pasted onto multiple terminal rows 5R all at once.

[0058] [Configuration Steps] The configuration step involves mounting the second electronic component 4 onto the first electronic component 3 through the connecting membrane 2. For example... Figure 1 As shown in (C), in the configuration step, the first terminal 5 or first terminal row 5R of the first electronic component 3 to which the adhesive layer 11 is transferred is aligned with the second terminal 6 or second terminal row 6R of the second electronic component 4 and mounted.

[0059] [Connection Steps] The connection step involves electrically and mechanically connecting the first electronic component 3 and the second electronic component 4 by pressing the second electronic component 4 and curing the connection film 2. For example... Figure 2 As shown, in the connection step, for example, with the buffer 17 in between, the first terminal 5 or the first terminal row 5R of the first electronic component 3 and the second terminal 6 or the second terminal row 6R of the second electronic component 4 are pressed using the crimping tool 18, and the adhesive layer 11 is cured by heating, light irradiation, etc., according to the curing type of the connection film 2.

[0060] Here, in the adhesive layer 11, tapered inclined portions 13 are formed at both ends of the main body portion 12 in the width direction 11W. Therefore, as Figure 2As shown, by applying pressure during the connection step, the amount of resin flowing between the terminals 6R and the terminals of the second terminal 6 is reduced. This allows for control of excessive resin flow, and furthermore, it facilitates control of particle trapping even when conductive particles are present. Moreover, when conductive particles are arranged in the adhesive layer 11, misalignment caused by resin flow can be suppressed. It should be noted that... Figure 2 This is a schematic diagram used to more clearly show the inclined portion 13 of the adhesive layer 11.

[0061] [Connection Structure] Figure 3 This is a cross-sectional view showing the connection structure 1. For example... Figure 3 As shown, the connecting structure 1 is formed by connecting the first terminal 5 of the first electronic component 3 and the second terminal 6 of the second electronic component 4 through a cured film 11A, which is formed by curing an adhesive layer 11. It should be noted that in the case of a heat-melt type connecting film 2, the cured film 11A is connected by melting and solidifying the heat-melt type connecting film 2. For convenience, the cured film 11A can also be considered to be heat-melt type. The first terminal 5 and the second terminal 6 are electrically connected via conductive particles contained in the adhesive layer 11 or through direct connection.

[0062] As described above, during the connection step, the amount of resin flowing to both ends of the terminal row 6R of the second terminal 6 is controlled, thus also controlling the formation of the chamfer 8 on the periphery of the second electronic component 4. That is, the chamfer 8 can be formed with an amount of resin sufficient to ensure the strength required for the connection of the second electronic component 4, eliminating unwanted resin and suppressing the expansion of the chamfer 8. This easily addresses the high density of the mounting area, allowing for the installation of many miniaturized electronic components. Furthermore, regarding the connection structure 1, the influence of resin flow during the connection step is suppressed, thus eliminating concerns about a decrease in the capture rate of conductive particles or misalignment, resulting in excellent connectivity.

[0063] Figure 5 This is a cross-sectional view showing the connection step in the manufacturing process of the connection structure shown for comparison. Figure 6 Through Figure 5 A cross-sectional view of the connecting structure manufactured using the shown manufacturing steps. (See attached image.) Figure 5 As shown, when no tapered inclined portions are formed on both ends of the main body of the adhesive layer, as indicated by the arrows in the figure, the insulating adhesive flows uniformly, resulting in a large amount of resin flowing at both ends of the second terminal row 6R, which diffuses in the mounting area. Therefore, there is a concern that this could lead to a decrease in the capture rate of conductive particles and misalignment. Furthermore, as... Figure 6As shown, unwanted resin can cause the chamfer 8 to expand, making it difficult to cope with the high density of the installation area. In addition, the flowing resin can also cause contamination of surrounding components and the workbench on which the first electronic component 3 is placed.

[0064] [Connecting membrane] Next, the structure of the connecting film 2 will be described. As described above, the connecting film 2 includes: a release film 10; and an adhesive layer 11, which is laminated along the longitudinal direction of the release film 10. The adhesive layer 11 includes: a main body portion 12 having a predetermined thickness; and tapered inclined portions 13 formed at both ends of the main body portion 12 in the width direction. It should be noted that the connecting film 2 is formed by providing an adhesive layer 11 of a predetermined shape along the longitudinal direction of the release film 10. Its shape can also be referred to as film-shaped, raised, or convex. In this specification, the term "film-shaped" is used in the sense that it encompasses these shapes.

[0065] [Mold release film] The release film 10 is a substrate obtained, for example, by a release treatment using silicone resin, as described below. Examples of release films 10 include PET (Poly Ethylene Terephthalate), OPP (Oriented Polypropylene), PMP (Poly-4-methylpentene-1), and PTFE (Polytetrafluoroethylene). Furthermore, in the release film 10, at least the side facing the adhesive layer 11 is subjected to a release treatment using silicone resin, for example.

[0066] The thickness of the release film 10 is not particularly limited. From the perspective of separation, the lower limit of the thickness is preferably 10 μm or more, more preferably 25 μm or more, and even more preferably 38 μm or more. If it is too thick, there is a concern that excessive pressure will be applied to the bonding film, so the upper limit of the thickness 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.

[0067] Furthermore, the width of the release film 10 is not particularly limited. The lower limit of the width can be 0.5 mm or more, and from a winding perspective, 1 mm or more is preferred, more preferably 2 mm or more, and even more preferably 4 mm or more. If it is too large, there are concerns about portability and ease of operation; therefore, the upper limit of the width is preferably 500 mm or less, more preferably 250 mm or less, and even more preferably 120 mm or less. In practical terms, to reduce equipment investment such as modifying the assembly roll device, it can also be 50 mm or less. When multiple release films 10 are provided, a larger area is required, so the upper limit can also be set large in this way.

[0068] [Adhesive layer] The adhesive constituting the adhesive layer 11 can be appropriately selected from insulating adhesives such as thermosetting, photocuring, photothermal curing, and hot-melt adhesives, depending on the purpose. Furthermore, the adhesive layer 11 can also be a conductive adhesive layer containing fillers such as conductive particles in an insulating adhesive. The conductive particles can be dispersed or arranged in the resin. Furthermore, when the conductive particles are dispersed in the resin, they can also separate independently without contact.

[0069] The lower limit of the thickness of the adhesive layer 11 can be, for example, the same as the diameter of the conductive particles, and is preferably set to 1.3 times or more the diameter of the conductive particles, or 2 μm or more, preferably 10 μm or more. Furthermore, the upper limit of the thickness of the adhesive layer 11 is, for example, set to 200 μm or less, preferably 100 μm or less, more preferably 40 μm or less, or less than twice the diameter of the conductive particles. When the adhesive layer 11 is composed of multiple layers, such as a laminated structure of conductive adhesive layers and insulating adhesive layers, the thickness is the total thickness of each layer.

[0070] Furthermore, the adhesive layer 11 can also be formed by laminating insulating adhesive layers and adhesive layers that do not contain conductive particles, and the number of layers and the lamination surfaces can be appropriately selected according to the object and purpose. Moreover, the insulating resin used as the insulating adhesive layer and adhesive layer can be the same insulating resin as that used in the conductive adhesive layer. The adhesive layer refers to a layer that does not contain a polymeric resin that reacts during the bonding step.

[0071] When the width of the adhesive layer 11 is less than 0.5 mm, it is formed with a relatively thin width. This provides an adhesive film that addresses the miniaturization of the mounting components, the narrowing of the mounting area, and the high density required. The lower limit of the width of the adhesive layer 11 is preferably 0.1 mm or more, more preferably 0.3 mm or more. The upper limit can be 0.95 times or less of the width of the release film, preferably 0.9 times or less, more preferably 0.8 times or less. When the length of the adhesive layer 11 is in the width direction of the release film 10, the upper limit can be 0.95 times or less of the width of the release film 10, preferably 0.9 times or less, more preferably 0.8 times or less.

[0072] As conductive particles, conductive particles used in known anisotropic conductive films can be appropriately selected and used. Examples include metal particles such as nickel, copper, silver, gold, and palladium; alloy particles such as solder; and metal-coated resin particles formed by coating the surface of metals such as nickel with resin particles such as polyamide and polybenzoguanamine. The surface can also be insulated to the extent that it impedes conductivity. Furthermore, the surface shape can have protrusions.

[0073] There is no particular limitation on the particle diameter of the conductive particles, but the lower limit can be 1 μm or more, preferably 2 μm or more. For example, from the viewpoint of the capture efficiency of conductive particles in the connecting structure, the upper limit of the particle diameter is preferably 50 μm or less, and more preferably 20 μm or less. It should be noted that the particle diameter of the conductive particles can be set as the value measured by an image-type particle size analyzer (for example, FPIA-3000: manufactured by Malvern). Preferably, the number is 1000 or more, and more preferably 2000 or more.

[0074] The number density of conductive particles can be appropriately adjusted within a range that does not affect the electrode size or film slicing of the connected objects. For example, it can be set to 30–500,000 particles / mm in a planar field of view. 2 Therefore, excellent conductivity and insulation can be achieved even with small electrode sizes of the connected objects. The number density of conductive particles is the number density of the conductive particles in the arrangement portion during film formation during manufacturing. This number density is preferably measured in the following manner: the conductive particles in the adhesive layer are observed using an optical microscope or a metal microscope under top-view observation, and the total area of ​​ten or more regions is set to 2 mm. 2 The total number of conductive particles is over 200. When the particle number density is calculated based on multiple individual pieces, the particle surface density can be calculated by subtracting the space between the individual pieces from the area containing the individual pieces and the space between them, and then calculating the particle number.

[0075] The insulating adhesive (insulating resin) can be any known insulating adhesive. Examples of curing types include thermosetting, photocuring, and a combination of photo- and thermo-curing types. Examples include photoradical polymerization resin compositions containing a (meth)acrylate compound and a photoradical polymerization initiator; thermal radical polymerization resin compositions containing a (meth)acrylate compound and a thermal radical polymerization initiator; thermal cationic polymerization resin compositions containing an epoxy compound and a thermal cationic polymerization initiator; and thermal anionic polymerization resin compositions containing an epoxy compound and a thermal anionic polymerization initiator. Furthermore, known adhesive compositions can also be used. In the case of a hot-melt type, the composition disclosed in Japanese Patent Application Publication No. 2014-060025 can be used. While a curing type is preferred for controlling resin flowability, a hot-melt type is preferred from the viewpoint of film storage; the choice depends on the intended purpose.

[0076] The following examples illustrate thermally free radical polymerized insulating adhesives containing film-forming resins, elastomers, (meth)acrylic acid monomers, polymerization initiators, and silane coupling agents. It should be noted that (meth)acrylic acid monomers refer to either acrylic acid monomers or methacrylic acid monomers.

[0077] There are no particular limitations on the film-forming resin used; examples include phenoxy resin, unsaturated polyester resin, saturated polyester resin, polyurethane resin, butadiene resin, polyimide resin, polyamide resin, and polyolefin resin. One film-forming resin can be used alone, or two or more can be used in combination. Among these, phenoxy resin is particularly preferred from the perspectives of film-forming properties, processability, and bonding reliability. Phenoxy resin is a resin synthesized from bisphenol A and epichlorohydrin; appropriately synthesized resins or 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.

[0078] There are no particular limitations on what can be considered as an elastomer; examples include polyurethane resin (polyurethane-based elastomer), acrylic rubber, silicone rubber, butadiene rubber, etc.

[0079] 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 polymer stress relief, it is preferred that 80% by mass or more of the (meth)acrylic acid monomer in the insulating adhesive is a monofunctional (meth)acrylic acid monomer.

[0080] Furthermore, from the viewpoint of adhesion, it is preferable that the monofunctional (meth)acrylic acid monomer contains a carboxylic acid. Moreover, 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.

[0081] As a polymerization initiator, any initiator capable of curing the (meth)acrylic acid monomer at the specified temperature during hot pressing is acceptable, with no particular limitations. Examples of organic peroxides include lauroyl peroxide, butyl peroxide, benzyl peroxide, dilauryl peroxide, di-tert-butyl peroxide, dicarbonate peroxide, and benzoyl peroxide. One or more of these initiators can be used alone or in combination. The content of the polymerization initiator in the insulating adhesive is not particularly limited, but is preferably 0.5% to 15% by mass.

[0082] There are no particular limitations on the silane coupling agent used; examples include epoxy-based silane coupling agents, acrylic-based silane coupling agents, thiol-based silane coupling agents, and amine-based silane coupling agents. The content of the silane coupling agent in the insulating adhesive is not particularly limited, but is preferably 0.1% to 5.0% by mass.

[0083] In addition to the aforementioned complexes, insulating adhesives may also contain fillers, softeners, accelerators, anti-aging agents, colorants (pigments, dyes), organic solvents, ion traps, etc., as needed. Colorants (pigments, dyes) may also be included to improve the visual visibility of the film. Furthermore, known insulating fillers (so-called nanofillers) may be included to adjust melt viscosity, etc.

[0084] [Inclined section] like Figure 7 As shown, the adhesive layer 11 has: a main body portion 12 having a predetermined thickness; and a tapered inclined portion 13 formed at both ends of the main body portion 12 in the width direction. As described later, the inclined portion 13 is formed by the portion where the thickness gradually decreases taperingly towards the ends of the adhesive (insulating adhesive) printed with a narrower width due to insufficient printing (skimming).

[0085] The inclined portion 13 refers to the area on both ends of the main body portion 12 in the width direction, where the thickness is less than 90% of the thickness of the main body portion 12. When the adhesive layer 11 is a conductive adhesive layer, the inclined portion 13 is a region where the coating thickness is thinner than the size (diameter) of the conductive particles.

[0086] In the adhesive layer 11, the ratio of the width 13W of the inclined portion 13 to the width 11W of the adhesive layer 11 is preferably 5% to 20%. If the ratio of the width 13W of the inclined portion 13 to the width 11W of the adhesive layer 11 is less than 5%, the overflow of the insulating adhesive of the connecting structure 1 will increase; if the ratio is more than 20%, the width 11W of the adhesive layer 11 will become narrower, and the effective width during installation will become narrower.

[0087] Furthermore, in the connecting film 2, the ratio of the width 11W of the adhesive layer 11 to the width 10W1 of the release film 10 is preferably 50% to 95%. If the ratio of the width 11W of the adhesive layer 11 to the width 10W1 of the release film 10 is less than 50%, the area of ​​the adhesive layer 11 coated on the release film 10 becomes smaller, and the release film 10 is wasted. If the ratio is greater than 95%, in the case of a narrower width, due to the serpentine cutting motion during slitting, the cutting edge may come into contact with the adhesive portion, posing a risk that the adhesive layer 11 may lift off the release film 10.

[0088] Furthermore, in the adhesive layer 11, the aspect ratio of the thickness 12H of the main body 12 to the width 13W of the inclined portion 13 is preferably 100% or more and 400% or less. When the thickness 12H of the main body 12 exceeds 400% of the width of the inclined portion 13, it is easy to form a chamfer, but it is difficult to keep the chamfer at an appropriate size, which raises concerns about contamination of other components. Therefore, the width 13W of the inclined portion 13 relative to the thickness 12H of the main body 12 is preferably 400% or less. Furthermore, if the thickness 12H of the main body 12 is less than 100% of the width 13W of the inclined portion 13, it is difficult to form a chamfer, which easily leads to a decrease in adhesive strength. Therefore, the width 13W of the inclined portion 13 relative to the thickness 12H of the main body 12 is preferably 100% or more.

[0089] In addition to having inclined portions 13 on both sides of the main body 12 in the width direction, the adhesive layer 11, as shown in the figure, has other features. Figure 8 As shown, the inclined portion 13 may be provided only on one side, while the other side has a cross-section 14 obtained by cutting along the thickness direction of the adhesive layer 11. Furthermore, as... Figure 9 As shown, the end of the inclined portion 13 may also have a cross-section 14 obtained by cutting in the thickness direction of the adhesive layer 11. The cross-section 14 can be formed, for example, by cutting the adhesive layer 11 in half in the thickness direction to the release film 10.

[0090] [Layered structure] Figure 10 This is a cross-sectional view showing an example of an adhesive layer 11 formed by stacking a conductive adhesive layer 19 and an insulating adhesive layer 20. Figure 10(A) represents an example of a coating structure in which the upper conductive adhesive layer 19 covers both sides of the lower insulating adhesive layer 20. Figure 10 (B) represents an example of a coating structure in which the upper insulating adhesive layer 20 covers both sides of the lower conductive adhesive layer 19. Figure 10 (C) indicates an example of a laminated structure in which the upper layer is a conductive adhesive layer 19 and the lower layer is an insulating adhesive layer 20. Figure 10 (D) indicates an example of a laminated structure in which the upper layer is an insulating adhesive layer 20 and the lower layer is a conductive adhesive layer 19.

[0091] A conductive adhesive layer 19 is provided on the upper layer. Figure 10 (A) Figure 10 In the configuration shown in (C), the first electronic component 3, for which the adhesive layer 11 is adhered, can preferably be a motherboard substrate such as a ceramic substrate, a rigid substrate, or a glass substrate. An insulating adhesive layer 20 is provided on the upper layer. Figure 10 (B) Figure 10 In the configuration shown in (D), the first electronic component 3 for which the adhesive layer 11 is attached can preferably be a flexible substrate, an IC module, an IC chip, or other components that are pressed by the pressing tool 18.

[0092] By making the adhesive layer 11 Figure 10 The configuration of the conductive adhesive layer 19 and the insulating adhesive layer 20 shown allows for further adjustment and control of the chamfer. This is because, although two or more layers are laminated, the diffusion of the resin during bonding, the ease of pressing, etc., can be adjusted by modifying the solid composition, insulating microfiller content, and melt viscosity of the layers on the release film 10 side and the layers above it. The solid content concentration of the coating liquid during the manufacturing of the bonding film in this invention, as well as the viscosity and melt viscosity of the bonding film after coating, can be appropriately designed according to the intended purpose.

[0093] [Manufacturing method of the connecting membrane] Next, the manufacturing steps of the connecting film 2 will be described. The manufacturing steps of the connecting film 2 include: an adhesive layer forming step, in which adhesive 21 is applied to the release film 10 in a predetermined shape and a plurality of adhesive layers 11 are formed on the release film 10 in a stripe pattern; and a slitting step, in which the release film 10 is slid according to the adhesive layers 11 with a predetermined width. Figure 11 This is a diagram showing the manufacturing steps of the connecting membrane 2. Figure 11 (A) is a perspective view showing the coating steps of adhesive 21. Figure 11 (B) is a perspective view showing the state in which multiple adhesive layers 11 are formed in a stripe pattern on the release film 10. Figure 11(C) is a perspective view showing the step of cutting the release film 10 to a specified width according to the adhesive layer 11.

[0094] [Adhesive layer formation steps] There are no particular limitations on the method of applying adhesive 21 to the release film 10. For example, known methods such as screen printing using a screen mask, inkjet printing for spraying the adhesive, and coating using a dispensing machine can be used. Screen printing is suitable for adhesives with insulating adhesives (ADH: Adhesive) and for paste-like adhesives regardless of whether solvents are used. It offers high freedom in the design / selection of adhesive components. Inkjet printing does not require a screen and can directly pattern based on data. The printing method can be selected by considering the properties of the release film 10, the adhesive 21, and the production cycle. The following explanation uses screen printing as an example.

[0095] Figure 11 (A) is a perspective view schematically illustrating an example of a printing step in a method for manufacturing the connecting film 2. Figure 12 This is a side view illustrating an example of the step of applying adhesive to the release film 10. (See example...) Figure 12 As shown, in the printing step, the adhesive 21 is printed (coated) onto the release film 10 by the pressure generated by the squeegee 22, etc., through the mesh of the screen mask 23. Figure 11 As shown in (B), multiple adhesive layers 11 are formed in a stripe pattern.

[0096] The linewidth of each adhesive layer 11 formed in a stripe pattern can be less than 1.0 mm, or it can be a finer width of less than 0.5 mm. For example, the lower limit of the linewidth of each adhesive layer 11 can be set to 0.1 mm or more. In conventional methods such as semi-cutting, it is difficult to manufacture a bonding film with an adhesive layer width less than 0.5 mm by comprehensively considering productivity and length scaling in the structure of the cutting blades for slitting and semi-cutting. However, by combining printing and slitting, adhesive layers 11 with a width less than 0.5 mm can be easily manufactured. This is particularly useful when manufacturing in long dimensions.

[0097] The adhesive layer 11 has tapered inclined portions 13 (whitening) formed on both ends in the width direction. When the adhesive layer 11 is a conductive adhesive layer, the inclined portions 13 are areas where the coating thickness is thinner than the size (diameter) of the conductive particles.

[0098] Furthermore, the width 13W of the inclined portion 13 (flying white) can be adjusted by changing the printing plate (screen mask) and printing pressure conditions during printing. That is, by changing the printing plate during printing, the ratio of the width 13W of the inclined portion 13 to the width 11W of the adhesive layer 11 can be adjusted. As a result, the width 13W of the inclined portion 13 can be adjusted according to the position on the substrate of the first terminal 5 on which the adhesive layer 11 is provided, so as not to contaminate the surrounding area with insulating adhesive during the connection step of pressing the second electronic component.

[0099] Furthermore, by changing the printing plate during printing, the aspect ratio of the thickness 12H of the main body 12 of the adhesive layer 11 to the width 13W of the inclined portion 13 can be adjusted. This aspect ratio can also be adjusted by the conditions of the coating liquid (compound, viscosity, concentration of solid components, solvent, etc.) and the printing conditions (printing pressure, drying, etc.), thus enabling more advanced designs.

[0100] It should be noted that the adhesive layers 11 formed in a stripe pattern can be formed as continuous solid lines of adhesive 21, or as continuous dashed or dotted lines of adhesive 21 with individual pieces of adhesive 21 spaced at fixed intervals of a specified length. That is, the areas forming the adhesive layers for bonding can also be formed discontinuously and dispersedly. In this case, the area of ​​the dots in the dotted lines preferably has a degree of magnitude that contributes to the performance of the bonded structure. A single "dot" can be considered, and in this case, a set of dots (i.e., the "dotted lines" for bonding) can also be considered to have an area that contributes to the bonding. Furthermore, individual pieces of different shapes can also be mixed in the stripes of an adhesive layer 11. The individual pieces can also be half-cut on the release film 10 (preferably after the drying step described later).

[0101] The screen mask 23 is a plate made of a mesh woven from synthetic fibers such as polyester, stainless steel, or various metal fibers. When the adhesive 21 contains conductive particles, the mesh openings only need to be larger than the maximum diameter of the conductive particles.

[0102] A drying step can also be performed after the adhesive 21 is applied. In the drying step, the adhesive 21, which is applied in a specified shape, is dried, forming an adhesive layer 11 of a specified shape on the release film 10. An oven or a blower is preferably used for drying. Furthermore, in the adhesive layer forming step, multiple adhesive layers 11 of specified shapes can be arranged in a fixed direction on the release film 10, and the arrangement of the adhesive layers 11 can be formed into a stripe pattern. As a result, a monolithic adhesive layer 11 corresponding to a substrate with a complex shape and a mounting area can be manufactured efficiently. In addition, compared to forming a monolithic sheet by setting and processing the film in the form of a blank roll, the amount of film raw materials and solvents used can be reduced, thus also helping to reduce the environmental impact.

[0103] It should be noted that conductive particles can also be configured after the adhesive 21 is coated. The conductive particles can be configured randomly or regularly. Examples of configuration methods include transfer printing. Examples of transfer printing methods include attaching conductive particles to the micro-adhesive layer of the transfer body, overlapping the attachment surface of the conductive particles of the transfer body with the adhesive 21 coated in a predetermined shape, and pressing them together, thereby transferring the conductive particles to the adhesive layer 11 of a predetermined shape. The transfer printing method is not limited to this. Furthermore, configuration methods other than transfer printing are not excluded. Multiple rows and columns of adhesive layers 11 can also be formed on a blank roll, and the release film 10 can be cut to form a single sheet. Alternatively, they can be transferred onto a long strip of release film 10.

[0104] [Slicing Steps] Next, as Figure 11 As shown in (C), the release film 10, on which multiple adhesive layers 11 are formed in a striped pattern, is cut along the stripes of the adhesive layers 11. This allows the formation of a connecting film 2 with adhesive layers 11 of a narrower width. Each connecting film 2 can also be made elongated by connecting multiple films together in the longitudinal direction as needed. Furthermore, as... Figure 13 As shown, the long strip of connecting membrane 2 can also be wound around the core 30 to form a membrane roll 31.

[0105] In the slitting step, only the release film 10 between the stripes of the adhesive layer 11 is slit, thereby forming a connecting film 2 with the adhesive layer 11 disposed on the inner side of the release film 10. Therefore, by adjusting the coating width of the adhesive layer 11 and the spacing of the stripes in the adhesive layer forming step, the ratio of the width 11W of the adhesive layer 11 to the width 10W1 of the release film 10 can be adjusted. Furthermore, by adjusting the spacing of the printing plate and the stripes of the adhesive 21 in the adhesive layer forming step, the ratio of the width 13W of the inclined portion 13 to the width 10W2 of the side edge portion from the side edge of the release film 10 to the adhesive layer 11 can be adjusted.

[0106] It should be noted that, during the slitting step, the release film 10 and the adhesive layer 11 can also be slitted together, thereby aligning the side of the adhesive layer 11 with the side of the release film 1. Alternatively, the adhesive layer 11 can be half-cut, thereby removing the inclined portion 13 at one end in the width direction of the adhesive layer 11, forming a cross-section 14 at the end of this end 12 (see reference). Figure 8 Alternatively, a cross-sectional surface 14, formed along the thickness direction of the adhesive layer 11, can be formed at the end of the inclined portion 13 (see reference). Figure 9 ).

[0107] Furthermore, in the slitting step, in addition to slitting each stripe of one adhesive layer 11, it is also possible to slit each of multiple stripes. That is, it is also possible to form multiple stripes of adhesive layers 11 on the release film 10 of the bonding film 2.

[0108] In addition to being composed of Figure 13 In addition to the film roll 31 shown, it can also be configured as a sheet on the release film 10 in which one or more adhesive layers 11 are arranged in a manner corresponding to a first electronic component 3 (see also Japanese Patent Application Laid-Open No. 2023-125888). Figure 2 (and the record). In addition, for the sheet-like connecting film 2, in addition to the scheme of configuring one connecting film 2 for one first electronic component 3, it is also possible to configure one connecting film 2 for two or more first electronic components 3.

[0109] Figure 14 This is a cross-sectional view showing other examples of the laminated configuration of conductive adhesive layer 19 and insulating adhesive layer 20. Figure 14 An adhesive layer 41A is formed in the connecting film 2 shown. This adhesive layer 41A is formed by providing an insulating adhesive layer 20 across the entire width of the release film 10, and a conductive adhesive layer 19 is stacked on the insulating adhesive layer 20 with a width smaller than the width of the insulating adhesive layer 20. The conductive adhesive layer 19 is stacked approximately at the center of the adhesive layer 41A in the width direction of the insulating adhesive layer 20.

[0110] Figure 15 It is used for Figure 14 The top view illustrating an example of the manufacturing process of the connecting membrane 2 is shown. Figure 15 As shown, an insulating adhesive layer 20 is formed by coating a resin composition of an insulating adhesive layer 20 all over the surface of a release film 10 and allowing it to dry. A plurality of adhesive layers 41A are formed side-by-side by coating a resin composition of a conductive adhesive layer 19 on the insulating adhesive layer 20 with a width smaller than the s section width along the longitudinal direction and allowing it to dry. The release film 10 and the insulating adhesive layer 20, which form gaps between the adhesive layers 41A, are then slit. Figure 15 In the example shown, the slits S1 to S5 along the length direction of the demolding membrane 10 are shown along the width direction of the membrane.

[0111] according to Figure 15The manufacturing example shown demonstrates that a connecting film 2 composed of an adhesive layer 41A having a width smaller than the cut width (width of the insulating adhesive layer 20) can be manufactured using a single slitting step. This allows for the simpler manufacturing of a connecting film 2 with a finer width compared to a manufacturing method that combines half-cutting and slitting. Furthermore, since the conductive adhesive layer 19 does not come into contact with the slitting blade, adhesion problems can be easily avoided.

[0112] In addition, such as Figure 16 As shown, the adhesive layer 41A can also be manufactured by forming a conductive adhesive film 42 on a film-like release substrate, on which a conductive adhesive layer 19 is supported, and similarly forming an insulating adhesive film 43 on a release treatment film 10, on which an insulating adhesive layer 20 is supported, and then bonding the conductive adhesive layer 19 of the conductive adhesive film 42 with the insulating adhesive layer 20 of the insulating adhesive film 43.

[0113] For the conductive adhesive film 42, a resin composition of the conductive adhesive layer 19 is applied to a release substrate using a doctor blade coater, coating device, etc., and the resin composition on the release substrate is dried using a hot drying oven, heating drying device, etc., thereby forming a conductive adhesive layer 19 of a specified thickness. The insulating adhesive film 43 is processed in the same way. The conductive adhesive film 42 and the insulating adhesive film 43 are bonded together by a bonding device 44, and a connecting film 2 having an adhesive layer formed by stacking the conductive adhesive layer 19 and the insulating layer 20 is produced by winding.

[0114] It should be noted that the connecting film 2 is not limited to the manufacturing method described above. Alternatively, the connecting film 2 can be made by bonding a rectangular conductive adhesive layer 19 cut into any width to an insulating adhesive layer 20 supported on an insulating peel treatment film 10.

[0115] Figure 17 This is a cross-sectional view showing a modified example of the adhesive layer 41. Figure 17 In the connecting film 2 shown, an adhesive layer 41B is formed. This adhesive layer 41B is formed by providing a conductive adhesive layer 19 across the entire width of the release film 10, and then stacking an insulating adhesive layer 20 on the conductive adhesive layer 19 with a width smaller than the width of the conductive adhesive layer 19. The manufacturing example of the adhesive layer 41B is the same as that of the adhesive layer 41A.

[0116] In the connecting membrane 2, such as Figure 14 As shown in the adhesive layer 41A, the conductive adhesive layer 19 can be formed approximately at the center of the width direction of the insulating adhesive layer 20, but it can also be as shown in the figure. Figure 18 The image shows a bias towards either the left or right. Figure 18In the connecting film 2 shown, an adhesive layer 41C is formed. This adhesive layer 41C is formed by providing an insulating adhesive layer 20 across the entire width of the release film 10, and a conductive adhesive layer 19 is stacked on the insulating adhesive layer 20 with a width smaller than the width of the insulating adhesive layer 20. Figure 18 In the example shown, for adhesive layer 41C, conductive adhesive layer 19 is stacked on the left side (one side) of the width direction of insulating adhesive layer 20, thereby providing a single-layer region 45 of insulating adhesive layer 20 without conductive adhesive layer 19 on the right end side (the other side) of conductive adhesive layer 19. The left end (one side) of conductive adhesive layer 19 is set to be approximately flush with the left end (one side) of release treatment film 10 and insulating adhesive layer 20 (arranged on the left end side (one side) of insulating adhesive layer 20).

[0117] By using the connecting film 2, which has an adhesive layer 41C formed by laminating an adhesive layer 19 on the insulating adhesive layer 20 with a width smaller than the width of the insulating adhesive layer 20 and biased towards the width direction, even when the adhesive layer 41C melts and flows when connecting the first electronic component 3 and the second electronic component 4, short circuits between terminals caused by the retention of conductive particles can be suppressed.

[0118] That is, assuming the flexible substrate or the like is the second electronic component 4, the molten adhesive layer 41C may flow onto the insulating protective film (solder resist) on the wiring pattern formed at the connection end of the flexible substrate. In this case, if the conductive particles contained in the adhesive layer are blocked by the insulating protective film, the conductive particles will remain in one place, potentially causing the terminals to conduct to each other. However, by arranging the single-layer region 45 of the insulating adhesive layer 20 towards the flexible substrate side, even if the adhesive layer 41C flows onto the insulating protective film, it will contain virtually no conductive particles, thus suppressing the retention of conductive particles and short circuits between terminals.

[0119] Figure 18 The ratio (20W:19W) of the width 20W of the insulating adhesive layer 20 to the width 19W of the conductive adhesive layer 19 in the adhesive layer 41C shown is preferably 11:10 to 18:1, and particularly preferably 9:7 to 18:1. Furthermore, Figure 18 The ratio (20W:45W) of the width 20W of the insulating adhesive layer 20 in the adhesive layer 41C to the width 45W of the single-layer region 45 is preferably 11:1 to 18:17, and particularly preferably 9:2 to 18:17.

[0120] In addition, such as Figure 19As shown, the connecting film 2 can also form an adhesive layer 41D, which is formed by providing a conductive adhesive layer 19 across the entire width of the release film 10, and stacking an insulating adhesive layer 20 on the conductive adhesive layer 19 with a width smaller than the width of the conductive adhesive layer 19 and biased towards one side of the width direction of the conductive adhesive layer 19. Figure 19 In the example shown, for adhesive layer 41D, insulating adhesive layer 20 is stacked biased to the left (one side) of conductive adhesive layer 19 in the width direction, thereby providing a single-layer region 46 of conductive adhesive layer 19 without insulating adhesive layer 20 on the right end (other side) of insulating adhesive layer 20. The left end (one side) of insulating adhesive layer 20 is set to be approximately flush with the left end (one side) of release treatment film 10 and conductive adhesive layer 19 (distributed biased to the left end (one side) of conductive adhesive layer 19).

[0121] By using the connecting film 2 with the adhesive layer 41D formed thereon, even when the adhesive layer 41D melts and flows during the connection of the first electronic component 3 and the second electronic component 4, the amount of resin flow itself can be reduced, the outflow of conductive particles can be suppressed, and stable particle trapping by the terminals can be achieved. That is, as described above, assuming that the flexible substrate or the like is the second electronic component 4, the molten adhesive layer 41D may flow onto the insulating protective film (solder resist) on the wiring pattern formed at the connection end of the flexible substrate. At this time, the adhesive layer 41D removes one side of the insulating adhesive layer 20 in the width direction, thereby reducing the amount of resin flow and suppressing the flow of conductive particles flowing with the resin. Therefore, the amount of particle flow is suppressed, and more particles remain on the terminals, resulting in stable conductivity.

[0122] It should be noted that the manufacturing examples of adhesive layers 41C and 41D are the same as those of adhesive layers 41A and 41B. Furthermore, Figure 19 The ratio of the width 19W of the preferred conductive adhesive layer 19 to the width 20W of the insulating adhesive layer 20 in the adhesive layer 41D shown is (19W:20W), and the ratio of the width 19W of the preferred conductive adhesive layer 19 to the width 46W of the monolayer region 46 is (19W:46W), which is the same as that of adhesive layer 41C.

[0123] Furthermore, the connecting film 2 can also remove one or both ends of the insulating adhesive layer 20 or the conductive adhesive layer 19 formed on the release film 10 in the width direction. As an example, Figure 20 This is a cross-sectional view showing the adhesive layer 41E after the ends of the insulating adhesive layer 20 formed on the release film 10 in the width direction have been removed. As an example, Figure 21This is a cross-sectional view showing the adhesive layer 41F after the ends of the conductive adhesive layer 19 formed on the release film 10 in the width direction have been removed. Only more than 50% of the central portion needs to remain at either end; there are no particular limitations on the extent of removal.

[0124] By using the connecting film 2 with the adhesive layer 41E formed thereon, even when the adhesive layers 41E and 41F melt and flow during the connection of the first electronic component 3 and the second electronic component 4, the amount of resin flow itself can be reduced, suppressing short circuits between terminals caused by the retention of conductive particles. That is, as described above, assuming the flexible substrate is the second electronic component 4, the molten adhesive layer 41E may flow onto the insulating protective film (solder resist) on the wiring pattern formed at the connection end of the flexible substrate. At this time, the adhesive layer 41E removes one or both sides of the insulating adhesive layer 20 in the width direction, so the amount of resin flow is small, and the amount of conductive particles flowing with the resin is also suppressed. Therefore, the retention of conductive particles and short circuits between terminals caused by the conductive particles being blocked by the insulating protective film can be suppressed. In this way, the influence of resin flow can be controlled by adjusting the amount of resin that affects the flow.

[0125] Furthermore, by using the connecting film 2 with the adhesive layer 41F formed thereon, even when the adhesive layer 41F melts and flows during the connection of the first electronic component 3 and the second electronic component 4, the amount of resin flow itself can be reduced, the outflow of conductive particles can be suppressed, and stable particle trapping by the terminals can be achieved. That is, as described above, assuming the flexible substrate or the like is the second electronic component 4, the molten adhesive layer 41F may flow onto the insulating protective film (solder resist) on the wiring pattern formed at the connection end of the flexible substrate. At this time, the adhesive layer 41F removes one or both sides of the insulating adhesive layer 20 in the width direction, so the amount of resin flow is small, and the amount of conductive particles flowing with the resin is also suppressed. Therefore, the amount of particle flow is suppressed, so more particles remain on the terminals, and stable conduction is achieved. That is, the influence of resin flow is controlled by adjusting the amount of resin that affects flow.

[0126] The insulating adhesive layer 20 in adhesive layers 41E and 41F can be formed, for example, by coating the entire surface of the release film 10 with a resin composition of the insulating adhesive layer 20 and allowing it to dry, thereby setting the insulating adhesive layer 20. A portion of the insulating adhesive layer 20 is removed along the longitudinal direction of the release film 10 by performing a semi-cutting process. The semi-cutting process uses a die-cutting blade to cut only the insulating adhesive layer 20 without cutting the release film 10, and the unwanted parts are removed by stamping or the like.

[0127] Next, a conductive adhesive layer 19 is laminated with a width smaller than that of the insulating adhesive layer 20. It should be noted that the formation of the conductive adhesive layer 19 can also be performed before the aforementioned semi-cutting process.

[0128] Alternatively, the insulating adhesive layer 20 in adhesive layer 41E and adhesive layer 41F can also be formed by printing the resin composition of the insulating adhesive layer 20 onto the release film 10 by screen printing or inkjet printing and then drying it.

[0129] Example [First Embodiment] The first embodiment of this technology will now be described. In the first embodiment, the following connecting film, evaluation substrate, and evaluation FPC are prepared.

[0130] (Connecting membrane) Five parts by weight of conductive resin core particles (Ni (substrate) / Au (surface) coating, resin core) with an average particle size of 20 μm and 95 parts by weight of insulating adhesive were added to a planetary mixing device (product name: Awatori Rentaro (Japanese)). (Made by THINKY Corporation), stir for 1 minute to prepare an anisotropic conductive paste.

[0131] The insulating adhesive is configured as a mixture of ethyl acetate and toluene, comprising 47 parts by weight of phenoxy resin (trade name: YP-50, manufactured by Shin-Nippon Chemical Epoxy Manufacturing Co., Ltd.), 3 parts by weight of monofunctional monomer (trade name: M-5300, manufactured by Toa Synthetic Co., Ltd.), 25 parts by weight of polyurethane resin (trade name: UR-1400, manufactured by Toyobo Co., Ltd.), 15 parts by weight of rubber component (trade name: SG80H, manufactured by Nagase ChemteX Co., Ltd.), 2 parts by weight of silane coupling agent (trade name: A-187, manufactured by Momentive Performance Materials Japan), and 3 parts by weight of organic peroxide (trade name: NYPERBW, manufactured by Nippon Oil Co., Ltd.) as 50% by weight of solid components.

[0132] The anisotropic conductive paste was applied to a release film (PET) using screen printing with a screen mask of a shape matching the mounting surface of the evaluation substrate, and then dried to create solid linear adhesive stripes with a thickness of 25 μm. The printing pressure was then changed from the baseline condition of 0.3 MPa to 0.15 MPa, resulting in two types of bonding films with different slope widths (blank widths). The sample with a small slope width (less than 50 μm) set to the baseline printing pressure of 0.3 MPa was designated as bonding film A, and the sample with a large slope width (more than 50 μm) set to the printing pressure of 0.15 MPa was designated as bonding film B. The release film was then cut along each stripe to obtain the bonding film.

[0133] For connecting membrane A, such as Figure 22 As shown in (A), an adhesive layer is made, and then as follows Figure 22 As shown in (B), a connecting film is formed with a cross-section obtained by slitting along the thickness direction on one side and a printing-specific inclined portion on the other side. The adhesive layer of the connecting film A has a width of 400 μm or less, and the width of the inclined portion is 50 μm or less.

[0134] like Figure 23 As shown in (A) and (B), the connecting film B is also formed with one side being straight and the other side having a printing-specific inclined portion. The adhesive layer of the connecting film B has a width of 400 μm or more, and the inclined portion has a width of 50 μm or more. Furthermore, a cross-section obtained by slitting along the thickness direction is formed on one side of the inclined portion.

[0135] (Evaluation substrate) An alumina ceramic substrate (tungsten wiring: line / space = 100um / 100um, wiring height: 10um, substrate thickness: 0.4mm) was prepared as the evaluation substrate for the bonding film to be adhered. Figure 24 As shown, the evaluation substrate has multiple terminals arranged near the side edge, and a film-like adhesive layer is pasted on the terminal row arranged along the side edge.

[0136] (Evaluation using FPC) As an evaluation FPC connected to the evaluation substrate through a connecting film, a flexible printed circuit board (copper wiring: line / space = 100um / 100um, terminal height: 12um, polyimide thickness: 25um) was prepared.

[0137] After the adhesive layer of the connecting film of the embodiments and comparative examples was adhered to the evaluation substrate, an evaluation FPC was mounted and hot-pressed (temperature: 140°C, pressure: 1 MPa, time: 6 sec) to produce a connecting structure. For the connecting structure, the overflow of electrical connections and insulating adhesive was evaluated. For electrical connections, all channels (ch) in the 30 channels formed between the evaluation substrate and the evaluation FPC were considered to be conductive (OK), and those with more than one channel not conductive were considered to be non-conductive (NG). For the overflow of insulating adhesive, the insulating adhesive was considered to be non-conductive if it did not flow outside the evaluation substrate when connecting to the evaluation FPC, and those that flowed outside the evaluation substrate were considered NG. As a comprehensive judgment, both electrical connections and the overflow of insulating adhesive were considered non-conductive, and either non-conductive was considered non-conductive.

[0138] [Example 1] like Figure 25 As shown in (A), using connecting film A, the side edge of the evaluation substrate is temporarily bonded to the inclined end of the adhesive layer, and then the evaluation FPC is installed. In this case, electrical connection is achieved by energizing regardless of the distance of the inclined width (30 / 30ch: qualified). Furthermore, no overflow of insulating adhesive was observed (overflow: qualified).

[0139] [Example 2] like Figure 25 As shown in (B), using the connecting film A, the side edge of the terminal of the evaluation substrate is temporarily bonded to the inclined end of the adhesive layer, and then the evaluation FPC is installed. In this case, even if the inclined part is on the terminal, power is applied without any problems and an electrical connection is obtained (30 / 30ch: qualified). Furthermore, no overflow of insulating adhesive was observed (overflow: qualified).

[0140] [Example 3] like Figure 25 As shown in (C), using the connecting film B, the side edge of the evaluation substrate is temporarily bonded to the inclined end of the adhesive layer, and then the evaluation FPC is installed. In this case, electrical connection is obtained without problems when power is applied (30 / 30ch: qualified). Furthermore, no overflow of insulating adhesive was observed (overflow: qualified).

[0141] [Comparative Example 1] like Figure 25As shown in (D), using the connecting film B, the side edge of the terminal of the evaluation substrate is temporarily bonded to the inclined side end of the adhesive layer, and then the evaluation FPC is installed. In this case, there are no conductive particles in the inclined portion, resulting in terminals that cannot be electrically connected due to uncaptured particles (28 / 30ch: non-compliant). No overflow of insulating adhesive was observed (overflow: compliant).

[0142] [Comparative Example 2] like Figure 25 As shown in (E), a temporary adhesive film B was used, extending at an angle from the side edge of the evaluation substrate, before the evaluation FPC was installed. In this case, electrical connection was achieved without problems when power was applied (30 / 30ch: pass), but overflow of insulating adhesive from the evaluation substrate was observed (overflow: fail). As shown in Table 1, it can be seen that by controlling the width of the inclined portion, a good connection between the terminals located near the side edge of the substrate and the electronic components can be established, and overflow of the insulating adhesive can be prevented. Furthermore, it can be seen that with a larger inclined portion width, the amount of insulating adhesive in the inclined portion is less, thus preventing overflow. Moreover, it can be seen that by controlling the width of the inclined portion, the influence of resin flow during the bonding step is suppressed, thus eliminating concerns about a decrease in the capture rate of conductive particles or misalignment, resulting in good connectivity.

[0143] [Second Embodiment] Next, a second embodiment of the present technology will be described. In the second embodiment, a connecting membrane without an inclined portion is prepared as the connecting membrane (see reference). Figure 5 The evaluation substrate used is the same as that used in the first embodiment.

[0144] [Example 4] An evaluation IC is used as an electronic component connected to the evaluation substrate. An anisotropic conductive paste, the same as in the first embodiment, is produced. Following the same screen printing and slitting steps as in the first embodiment, a bonding film is formed with an adhesive layer having a width of 1.8 mm, a thickness of 25 μm, and a width of 200 μm for the inclined portion.

[0145] After the adhesive layer of the connection film of Example 4 was adhered to the evaluation substrate, the evaluation IC was mounted and hot-pressed (temperature: 140°C, pressure: 60 MPa, time: 6 sec) to create the connection structure. The chamfer width (mm) of the connection structure was measured and found to be 310 μm.

[0146] [Example 5] As an electronic component connected to the evaluation substrate, an evaluation FPC is used. An anisotropic conductive paste, the same as in the first embodiment, is produced. Following the same screen printing and slitting steps as in the first embodiment, a bonding film is formed with an adhesive layer having a width of 2.0 mm, a thickness of 25 μm, and a width of 200 μm for the inclined portion.

[0147] After the adhesive layer of the connecting film of Example 5 was adhered to the evaluation substrate, an evaluation FPC was mounted on it and hot-pressed (temperature: 140°C, pressure: 1 MPa, time: 6 sec) to produce a connecting structure. The chamfer width (mm) of the connecting structure was measured and found to be 90 μm.

[0148] [Comparative Example 3] As an electronic component connected to the evaluation substrate, the same evaluation IC as in Example 3 was used. An anisotropic conductive paste, the same as in the first embodiment, was fabricated, and a bonding film with an adhesive layer having a width of 1.8 mm and a thickness of 25 μm was produced through the same screen printing and slitting steps as in the first embodiment. The bonding film of Comparative Example 3 did not have a tilted portion.

[0149] After the adhesive layer of the connection film of Comparative Example 3 was adhered to the evaluation substrate, the evaluation IC was mounted and thermo-pressed (temperature: 140°C, pressure: 60 MPa, time: 6 sec) to create the connection structure (see reference). Figure 6 The chamfer width (mm) of the connecting structure was measured, and the result was 460 μm.

[0150] [Comparative Example 4] As an electronic component connected to the evaluation substrate, the same evaluation FPC as in Example 4 was used. An anisotropic conductive paste, the same as in the first embodiment, was fabricated, and similarly to Comparative Example 3, a bonding film was fabricated having an adhesive layer with a width of 2.0 mm and a thickness of 25 μm. The bonding film of Comparative Example 4 did not have a tilted portion.

[0151] After the adhesive layer of the connecting film of Comparative Example 4 was adhered to the evaluation substrate, an evaluation FPC was mounted on it and hot-pressed (temperature: 140°C, pressure: 1 MPa, time: 6 sec) to produce a connecting structure. The chamfer width (mm) of the connecting structure was measured, and the result was 280 μm. As shown in Table 2, compared to Comparative Example 3, which used a connecting film without a tilted portion, Example 4, which used a connecting film with a tilted portion, had a narrower chamfer width when connecting the same evaluation IC. Similarly, compared to Comparative Example 4, which used a connecting film without a tilted portion, Example 5, which used a connecting film with a tilted portion, had a narrower chamfer width when connecting the same evaluation FPC.

[0152] Therefore, by using a connecting film with an inclined portion, regardless of the type of the second electronic component (IC, FPC), the required amount of resin can be used to form a chamfer, unnecessary resin can be eliminated, and the expansion of the chamfer can be suppressed. This makes it easy to handle high-density mounting areas, thereby enabling the installation of many miniaturized electronic components.

[0153] Explanation of reference numerals in the attached figures 1: Connecting structure; 2: Connecting film; 3: First electronic component; 4: Second electronic component; 5: First terminal; 6: Second terminal; 10: Demolding film; 11: Adhesive layer; 11A: Curing film; 12: Main body; 13: Inclined part; 16: Substrate side edge; 17: Buffer; 18: Crimping tool; 19: Conductive adhesive layer; 20: Insulating adhesive layer; 21: Adhesive; 22: Scraper; 23: Screen mask.

Claims

1. A method for manufacturing a connecting structure, the connecting structure being formed by connecting a first terminal of a first electronic component having a first terminal and a second terminal of a second electronic component having a second terminal through a cured film, the cured film being formed by curing an adhesive layer of the connecting film, the method for manufacturing the connecting structure comprising: The pasting step involves pasting the adhesive layer of the connecting film onto the first electronic component; The configuration step involves placing the second terminal onto the first terminal through the adhesive layer; and In the connection step, press the second electronic component to cure the adhesive layer. The adhesive layer has: a main body having a specified thickness; and tapered inclined portions formed at both ends of the main body in the width direction. In the pasting step, the main body is aligned with the first terminal and pasted in the width direction of the adhesive layer.

2. The method for manufacturing the connecting structure according to claim 1, wherein, The adhesive layer is either a conductive adhesive layer containing conductive particles or an insulating adhesive layer that does not contain conductive particles.

3. The method for manufacturing the connecting structure according to claim 1, wherein, The adhesive layer has a conductive adhesive layer containing conductive particles and an insulating adhesive layer that does not contain conductive particles.

4. The method for manufacturing the connecting structure according to claim 1 or 2, wherein, The width of the adhesive layer is less than 0.5 mm.

5. The method for manufacturing the connecting structure according to claim 1 or 2, wherein, In the pasting step, the first terminal is formed near the side edge of the first electronic component, and the side edge of the first electronic component is aligned with the end of the inclined portion for pasting.

6. A connecting membrane, comprising: Release film; and An adhesive layer is stacked along the longitudinal direction of the release film. The adhesive layer has: a main body having a specified thickness; and tapered inclined portions formed at both ends of the main body in the width direction, wherein the width of the inclined portions is 5% to 20% of the width of the adhesive layer.

7. The connecting membrane according to claim 6, wherein, The width of the adhesive layer is 50% to 95% of the width of the release film.

8. The connecting membrane according to claim 6, wherein, The width of the adhesive layer is less than 0.5 mm.

9. The connecting membrane according to any one of claims 6 to 8, wherein, The adhesive layer is either a conductive adhesive layer containing conductive particles or an insulating adhesive layer that does not contain conductive particles.

10. The connecting membrane according to any one of claims 6 to 8, wherein, The adhesive layer has a conductive adhesive layer containing conductive particles and an insulating adhesive layer that does not contain conductive particles.

11. The connecting membrane according to any one of claims 6 to 8, wherein, One end of the inclined portion is configured as a cross-section in the thickness direction, and the other end of the inclined portion is configured as an inclined surface toward the demolding film.

12. The connecting membrane according to any one of claims 6 to 8, wherein, The adhesive layer is formed as continuous dashed or dotted lines, with individual pieces of the adhesive of a specified length spaced at fixed intervals.

13. The connecting membrane according to claim 10, wherein, The insulating adhesive layer is formed across the entire width of the release film. The conductive adhesive layer is stacked on the insulating adhesive layer with a width smaller than that of the insulating adhesive layer.

14. The connecting membrane according to claim 13, wherein, The conductive adhesive layer is formed approximately at the center of the width direction of the insulating adhesive layer.

15. The connecting membrane according to claim 13, wherein, The conductive adhesive layer is formed biased toward one side of the width direction of the insulating adhesive layer, and a single-layer region of the insulating adhesive layer is provided on the other side of the width direction of the insulating adhesive layer.

16. The connecting membrane according to claim 13, wherein, One or both ends of the insulating adhesive layer in the width direction are removed.

17. The connecting membrane according to claim 10, wherein, The conductive adhesive layer is formed across the entire width of the release film. The insulating adhesive layer is stacked on the conductive adhesive layer with a width smaller than that of the conductive adhesive layer.

18. The connecting membrane according to claim 17, wherein, The insulating adhesive layer is formed approximately at the center of the width direction of the conductive adhesive layer.

19. The connecting membrane according to claim 17, wherein, The insulating adhesive layer is formed biased toward one side of the width direction of the conductive adhesive layer, and a single-layer region of the conductive adhesive layer is provided on the other side of the width direction of the conductive adhesive layer.

20. The connecting membrane according to claim 17, wherein, One or both ends of the conductive adhesive layer in the width direction are removed.

21. A method for manufacturing a connecting membrane, comprising: The adhesive layer forming step involves applying adhesive in a predetermined shape onto a release film, and forming multiple adhesive layers in a stripe pattern on the release film; and In the slitting step, the release film is slitted to a specified width according to the adhesive layer. The adhesive layer is cut in such a way that a main body with a specified thickness is formed and tapered inclined portions are formed on both ends of the main body in the width direction, wherein the width of the inclined portions is 5% to 20% of the width of the adhesive layer.

22. The method for manufacturing the connecting membrane according to claim 21, wherein, The release film is cut according to each of one or more of the adhesive layers.

23. The method for manufacturing the connecting membrane according to claim 21, wherein, The width of the adhesive layer is less than 0.5 mm.

24. The method for manufacturing the connecting membrane according to any one of claims 21 to 23, wherein, The connecting membrane has a conductive adhesive layer containing conductive particles.

25. The method for manufacturing the connecting membrane according to claim 24, wherein, The adhesive layer has an insulating adhesive layer that does not contain conductive particles.

26. The method for manufacturing the connecting membrane according to any one of claims 13 to 15, wherein, The adhesive layer is formed as continuous dashed or dotted lines, with individual pieces of the adhesive of a specified length spaced at fixed intervals.

27. The method for manufacturing the connecting membrane according to claim 25, wherein, The insulating adhesive layer is formed across the entire width of the release film. The conductive adhesive layer is stacked on the insulating adhesive layer with a width smaller than that of the insulating adhesive layer.

28. The method for manufacturing the connecting membrane according to claim 27, wherein, The conductive adhesive layer is formed approximately at the center of the width direction of the insulating adhesive layer.

29. The method for manufacturing the connecting membrane according to claim 27, wherein, The conductive adhesive layer is formed biased toward one side of the width direction of the insulating adhesive layer, and a single-layer region of the insulating adhesive layer is provided on the other side of the width direction of the insulating adhesive layer.

30. The method for manufacturing the connecting membrane according to claim 27, wherein, One or both ends of the insulating adhesive layer in the width direction are removed.

31. The method for manufacturing the connecting membrane according to claim 25, wherein, The conductive adhesive layer is formed across the entire width of the release film. The insulating adhesive layer is stacked on the conductive adhesive layer with a width smaller than that of the conductive adhesive layer.

32. The method for manufacturing the connecting membrane according to claim 31, wherein, The insulating adhesive layer is formed approximately at the center of the width direction of the conductive adhesive layer.

33. The method for manufacturing the connecting membrane according to claim 31, wherein, The insulating adhesive layer is formed biased toward one side of the width direction of the conductive adhesive layer, and a single-layer region of the conductive adhesive layer is provided on the other side of the width direction of the conductive adhesive layer.

34. The method for manufacturing the connecting membrane according to claim 31, wherein, One or both ends of the conductive adhesive layer in the width direction are removed.

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