Anisotropic conductive film

Abstract

Provided is an anisotropic conductive film that, whether in a case where axes of each terminal of a terminal row are aligned side by side in the same direction or in a case of a fan-out type in which they are radiated, ensures a good conduction state by sandwiching each terminal with sufficient conductive particles and makes the capture state of the conductive particles at each terminal uniform, and even if terminals of a fine pitch are connected, prevents the occurrence of short circuits. This anisotropic conductive film (10A) has conductive particles (2) disposed in an insulating resin layer (3). In the xy plane of the anisotropic conductive film (10A) viewed from above, the zigzag-shaped arrangement R in which the arrangement Rb in which the conductive particles (2) are arranged at a positive slope and the arrangement Rc in which the conductive particles (2) are arranged at a negative slope are repeatedly arranged at a predetermined interval in the y direction is arranged at a predetermined pitch in the x direction while periodically changing the position in the y direction. The conductive particles thereby become a pseudo-random type regular arrangement (1A).

Description

TECHNICAL FIELD

[0001] The present application relates to an anisotropic conductive film. BACKGROUND

[0002] Since a substrate on which an electronic component such as an IC chip is mounted is required to be lightweight and bendable, a plastic substrate or an FPC (Flexible Printed Circuit) is often used. In addition, in an electronic component such as an IC chip, miniaturization of terminals is being promoted, and in mounting the electronic component, there are cases where thermal expansion of the plastic substrate or the FPC becomes a problem. Therefore, in order to reliably perform connection of the electronic component even if the position of the terminal deviates due to temperature variation at the time of mounting the electronic component, instead of the conventional side-by-side in the same direction and side-by-side in a radial direction (so-called fan-out wiring) (Patent Document 1), each terminal of a terminal row constituting the electronic component is arranged.

[0003] In addition, in addition to the fan-out arrangement, a unique electrode arrangement different from the past is also required in an LED element (so-called micro LED, mini LED) and the like.

[0004] On the other hand, an anisotropic conductive film in which conductive particles are dispersed in an insulating resin layer is widely used in mounting of electronic components. In order to stably capture the conductive particles of the anisotropic conductive film to the terminals of the electronic component even if the miniaturization of the terminals of the electronic component is performed in connection of the electronic component using the anisotropic conductive film, a scheme in which the conductive particles are arranged in a lattice shape such as a hexagonal lattice in the anisotropic conductive film and the arrangement axis is inclined with respect to the long side direction of the terminal is proposed (Patent Document 2). In addition, as the particle arrangement of the anisotropic conductive film, a scheme in which the conductive particles are arranged in a first direction inclined with respect to the long side direction of the film, and a plurality of particle rows of the first direction are arranged side by side in a second direction different from the arrangement direction, the particle row of the first direction is not made in a straight line shape, and the particle row has a width smaller than 2.5 times the particle diameter of the conductive particle (Patent Document 3); or a scheme in which units in which the conductive particles are arranged at a predetermined interval are repeatedly arranged (Patent Documents 4 and 5) and the like are proposed.

[0005] PRIOR ART DOCUMENTS

[0006] PATENT DOCUMENTS

[0007] Patent Document 1: Japanese Patent Application Publication No. 2015-232660

[0008] Patent Document 2: Japanese Patent Application Publication No. H9-320345

[0009] Patent Document 3: Japanese Patent Application Publication No. 2017-168465

[0010] Patent Document 4: Japanese Patent Application Publication No. 2017-204462

[0011] Patent document 5: Japanese Patent Application Publication No. 2017-204463. Summary of the Invention

[0012] (The problem that the invention aims to solve)

[0013] However, when using anisotropic conductive films for applications such as FOG (Film On Glass) bonding, such as... Figure 11A As shown, the connected terminals 20 are arranged side by side in the same direction. Even though the conductive particles 2 of the anisotropic conductive film are arranged in a hexagonal lattice and their arrangement axis is tilted at an angle δ relative to the long side direction of the terminal 20 (the direction perpendicular to the arrangement direction x), resin flow in the direction of the arrow occurs between the terminals due to the heat-pressing during connection. Therefore, depending on the conditions, such as Figure 11B As shown, the dense region A of conductive particles 2 generated between the connected terminals will become the cause of a short circuit.

[0014] In addition, such as Figure 12A As shown, when using an anisotropic conductive film with conductive particles 2 arranged in a hexagonal grid, and with the arrangement axis of the hexagonal grid tilted relative to the long side direction of the film (tilt angle γ), to connect a fan-out type terminal array, the overall fan-out angle β (i.e., the angle of the long side direction of terminal 20 relative to the arrangement direction x of the terminals) varies slightly for each terminal. Therefore, the number or distribution of conductive particles 2 captured by a terminal on the right and left sides of the fan-out type terminal array will differ, resulting in different appearances of the indentation after connection. Furthermore, in the conductive particle configuration shown in the same figure, in the temporary adhesive state before heat pressing of the terminal array, the conductive particles 2 on the terminal 20a on the left side of the paper are only captured at the edge of the terminal, which may cause poor conductivity after connection.

[0015] Furthermore, when using anisotropic conductive films with conductive particles arranged in a hexagonal lattice to connect terminal rows, the number of conductive particles (a certain number) along an alignment axis perpendicular to the terminal's x-direction is affected by trapping. This varies from terminal to terminal, with significant deviations in the number of particles trapped by a single terminal, and the distribution of the trapped number may exhibit two peaks. This is not limited to hexagonal lattices; it can also occur in square or rhomboid lattices. For example, as... Figure 12B As shown, the conductive particles 2 captured by terminal 20b belong to an arrangement axis y1 perpendicular to the arrangement direction x of the terminal, but conductive particles 2 belonging to two arrangement axes y2 and y3 are captured in terminal 20c. Figure 12CAs shown, in a terminal column in which the terminal column is not fan-out type and the axes of the terminals are in the same direction, this phenomenon becomes more pronounced, there are a considerable number of one arrangement axis yl involved in the connection of the terminal 20b and two arrangement axes y2, y3 involved in the connection of the terminal 20c, respectively, and the deviation in the number of conductive particles captured by one terminal becomes large. Therefore, when a graph of the number of conductive particles captured at one terminal and the frequency of occurrence of the terminal of the number of the captured is drawn, sometimes it becomes a plurality of peaks. That is, due to a plurality of main factors such as terminal width and terminal-to-terminal interval, and particle diameter and particle-to-particle distance, for example, there are cases where two peaks are found. Two peaks do not immediately cause a problem in actual use, but one peak side is easy to control the number of conductive particles captured.

[0016] In addition, due to the thermal compression bonding at the time of connection, the interval of the conductive particles on the terminal is greatly expanded in the short side direction compared to the long side direction of the terminal, the conductive particles on the terminal are squeezed out to the terminals, and the conductive particles present in the terminals including the squeezed-out conductive particles move due to the resin flow at the time of thermal compression bonding. Therefore, on the right and left sides of the terminal column, the distribution of the conductive particles with respect to the terminals is different, and if a dense portion of the conductive particles is formed between the terminals, there is a problem that short circuit is easily caused in that portion.

[0017] Whether the terminal column is in a radial fan-out type or in a straight terminal straight and side-by-side in the same direction (straight parallel arrangement), the phenomenon of short circuit of the conductive particles between the terminals due to the resin flow at the time of thermal compression bonding occurs. In response to this, it is conceivable to use a photocurable resin in the insulating resin layer of the anisotropic conductive film to reduce the movement of the conductive particles caused by the resin flow. However, if the use of a photocurable resin is used to provide a state in which the resin layer to be cured at the time of connection is mixed with a photocured resin, thereby suppressing the resin flow of the conductive particles, it is easy to become insufficiently pressurized to the conductive particles at the time of thermal compression bonding, and there is a possibility that connection failure occurs between the terminals and the conductive particles. Therefore, as described in Japanese Patent No. 6187665, it is also conceivable to increase the melt viscosity of the insulating resin layer by including a filler or the like in the insulating resin layer to sufficiently pressurize while suppressing the resin flow at the time of thermal compression bonding. However, whether it is a straight parallel arrangement type terminal column or a fan-out type terminal column, it is more difficult to cause a short circuit. This is because it is difficult to completely prevent the short circuit of the conductive particles by only maintaining the curing property or viscosity of the insulating resin of the conductive particles. Especially in the case of continuously manufacturing many connection structures on a production line or the like responsible for the connection process, there is a problem that it is not possible to completely prevent the occurrence of a short circuit when irregular resin flow or alignment deviation occurs. Furthermore, if the terminal layout or the material of the electronic component is diversified, it becomes more difficult to balance ensuring conduction and preventing short circuits in any terminal layout or material of the electronic component.

[0018] In order to stabilize the number of captured conductive particles at each terminal and suppress short-circuiting due to resin flow, as described in Patent Literature 3, when the first particle row of conductive particles is not made linear and the particle row is made to have a width of the particle diameter or more, the particle arrangement cannot be strictly controlled, and thus it is difficult to converge the number of captured conductive particles at each terminal to a predetermined range. In this case, if irregular resin flow or misalignment occurs in a production line or the like for continuously manufacturing the connection structure, it becomes more difficult to converge the number of captured conductive particles to within the predetermined range. The more the number of connection structures manufactured continuously, the higher the difficulty.

[0019] In addition, regarding the particle arrangement, even when a unit in which conductive particles are arranged repeatedly as described in Patent Literatures 4 and 5, it is difficult to make the distribution of conductive particles equal on the right side and the left side of the terminal row on the fan-out side, and this tendency is stronger when the terminal length is shorter, and it is difficult to reduce the deviation in the number of captured conductive particles at each terminal.

[0020] To address the above problems, an object of the present application is to make the captured state of conductive particles at the terminals after connection the same, regardless of whether the axes of the terminals of the terminal row to be connected are aligned in the same direction and the terminal row is straight or is a fan-out type, and to be able to ensure a good conduction state by clamping sufficient conductive particles on each terminal, and in addition, to be able to prevent the occurrence of short-circuiting when connecting terminals of which the pitch is fine.

[0021] (Solution for solving the problem)

[0022] Regarding the arrangement of conductive particles in the anisotropic conductive film, when a zigzag-shaped arrangement R in which conductive particles extending in the y direction are arranged at a predetermined pitch in the x direction while periodically changing the position in the y direction is arranged, the conductive particles are arranged in a pseudo-random pattern, and thus the present inventors have conceived that the above problems can be solved, and have completed the present application.

[0023] That is, the present application provides an anisotropic conductive film in which conductive particles are arranged in an insulating resin layer, in which, in the xy plane of the anisotropic conductive film viewed from above, a zigzag-shaped arrangement R in which an arrangement Rb in which conductive particles are arranged at a positive slope and an arrangement Rc in which conductive particles are arranged at a negative slope are repeatedly arranged at a predetermined interval in the y direction is arranged while periodically changing the position in the y direction and arranging conductive particles at a predetermined pitch in the x direction.

[0024] In addition, the present application provides a method for manufacturing a connection structure that anisotropically and electrically connects a terminal of a first electronic component and a terminal of a second electronic component using the above-described anisotropic conductive film.

[0025] Further, the present application provides a connection structure in which a first electronic component and a second electronic component are anisotropically electrically connected via the anisotropic conductive film.

[0026] Further, in the present application, the anisotropic conductive film refers to a film capable of forming an anisotropic conductive connection. In addition, the anisotropic conductive connection state refers to a state in which the facing terminals of electronic components each having a plurality of terminals are electrically connected to each other, but the adjacent terminals are not electrically connected to each other.

[0027] (EFFECTS OF INVENTION)

[0028] In the anisotropic conductive film of the present application, the arrangement of the conductive particles under plan view observation is a pseudo-random regular arrangement. Here, the pseudo-random regular arrangement is a random uniform arrangement in which the arrangement of the conductive particles appears to have no regularity or reproducibility, but actually has reproducibility or regularity. According to the anisotropic conductive film of the present application, since the arrangement of the conductive particles is a pseudo-random regular arrangement, and the conductive particles are uniformly distributed to a degree that cannot be recognized as uneven even under microscopic observation, sufficient conductive particles can be uniformly captured in a long transverse terminal or a special-shaped wiring bump regardless of whether the axes of the terminals of the connected terminal rows are aligned in the same direction and the terminal rows are straight or in a fan-out type, and thus a good conduction state is obtained.

[0029] In addition, a good conduction state can be obtained regardless of the direction in which the anisotropic conductive film is attached to the terminals.

[0030] Further, since the conductive particles are uniformly dispersed, even if terminals of a fine pitch are connected, the occurrence of short circuits can be suppressed.

[0031] Moreover, since the pseudo-random regular arrangement has a predetermined periodicity, in the product inspection of the anisotropic conductive film, it can be easily checked whether the conductive particles are arranged in the predetermined pseudo-random regular arrangement. BRIEF DESCRIPTION OF DRAWINGS

[0032] FIG. 1A-1 is a pseudo-random regular arrangement 1A of conductive particles possessed by the anisotropic conductive film 10A of the embodiment.

[0033] FIG. 1A-2 is an enlarged view of FIG. 1A-1.

[0034] Figure 1B is a schematic view of a method of producing the pseudo-random regular arrangement 1A of conductive particles possessed by the anisotropic conductive film 10A of the embodiment.

[0035] Figure 2 is a cross-sectional view of the anisotropic conductive film 10A of the embodiment.

[0036] Figure 3A is a cross-sectional view of an anisotropic conductive film 10B of an embodiment.

[0037] Figure 3B is a cross-sectional view of an anisotropic conductive film 10C of an embodiment.

[0038] Figure 4A is a pseudo-random regular arrangement IB of conductive particles that an anisotropic conductive film of an embodiment has.

[0039] Figure 4B is an explanatory view of a method of creating the pseudo-random regular arrangement IB of conductive particles that an anisotropic conductive film of an embodiment has.

[0040] Figure 5A is a pseudo-random regular arrangement IC of conductive particles that an anisotropic conductive film of an embodiment has.

[0041] Figure 5B is an explanatory view of a method of creating the pseudo-random regular arrangement IC of conductive particles that an anisotropic conductive film of an embodiment has.

[0042] Figure 6 is a pseudo-random regular arrangement ID of conductive particles that an anisotropic conductive film of an embodiment has.

[0043] Figure 7 is a pseudo-random regular arrangement IE of conductive particles that an anisotropic conductive film of an embodiment has.

[0044] Figure 8A is a pseudo-random regular arrangement IF of conductive particles that an anisotropic conductive film of an embodiment has.

[0045] Figure 8B is a pseudo-random regular arrangement IF of conductive particles that an anisotropic conductive film of an embodiment has.

[0046] Figure 9 is a pattern IB1 of conductive particles that an anisotropic conductive film of an embodiment has.

[0047] Figure 10 is a pattern IX of conductive particles that an anisotropic conductive film of a comparative example has.

[0048] Figure 11A is an explanatory view of a particle arrangement in which conductive particles are arranged in a hexagonal lattice.

[0049] Figure 11B is an explanatory view of a state after a terminal column is connected using an anisotropic conductive film in which conductive particles are arranged in a hexagonal lattice.

[0050] Figure 12Ais a plan view of a state of an anisotropic conductive film in which conductive particles are arranged in a hexagonal lattice (inclination angle γ) overlapping a terminal column of a fan-out type.

[0051] Figure 12B is a plan view of a state of an anisotropic conductive film in which conductive particles are arranged in a hexagonal lattice (inclination angle γ = 0°) overlapping a terminal column of a fan-out type.

[0052] Figure 12C is a plan view of a state of an anisotropic conductive film in which conductive particles are arranged in a hexagonal lattice (inclination angle γ = 0°) overlapping a terminal column in which terminal axes of respective terminals are in the same direction. DETAILED DESCRIPTION

[0053] Hereinafter, an anisotropic conductive film of an embodiment of the present application will be described in detail with reference to the accompanying drawings. In addition, in each drawing, the same reference numerals denote the same or equivalent constituent elements.

[0054] <Overall configuration of anisotropic conductive film>

[0055] Fig. 1A-1 is a plan view showing arrangement of conductive particles of an anisotropic conductive film 10A of the embodiment, and indicates a pseudo-random type regular arrangement 1A which the anisotropic conductive film has. Fig. 1A-2 is an enlarged view of Fig. 1A-1. Figure 2 is a cross-sectional view of the anisotropic conductive film 10A cut along a thickness direction.

[0056] The anisotropic conductive film 10A has a layer structure in which the conductive particles 2 are arranged in a single layer on a surface of or in the vicinity of the insulating resin layer 3, and the low-viscosity resin layer 4 is laminated thereon. In addition, in the present application, the low-viscosity resin layer 4 can be provided as needed, like the anisotropic conductive film 10B shown in a cross-sectional view of Figure 3A the anisotropic conductive film 10B. The planar arrangement of the conductive particles 2 of the anisotropic conductive film 10B can be made the same as that of the anisotropic conductive film 10A having the low-viscosity resin layer 4. As the layer structure of the anisotropic conductive film, like the anisotropic conductive film 10C shown in Figure 3B Fig. 1A-3, the conductive particles 2 can be held in through holes 3h of the insulating film 3 having the through holes 3h, and the low-viscosity resin layers 4A, 4B can be laminated on the upper and lower surfaces thereof. In this case, the insulating film 3 is a resin layer which is less likely to be deformed by heating and pressurization than the low-viscosity resin layers 4A, 4B.

[0057] <Conductive particles>

[0058] • Particle material

[0059] As the conductive particles 2, metal particles such as nickel, cobalt, silver, copper, gold, and palladium, alloy particles such as solder, and metal-coated resin particles can be given. Two or more kinds thereof can be used together. Among them, the metal-coated resin particles are preferable in that the contact with the terminal is easily maintained after connection due to the repulsion of the resin particles, and the conduction performance is stable. In addition, the surface of the conductive particles can be subjected to an insulating treatment that does not hinder the conduction characteristics. For example, an insulating fine particle can be attached by a known technique, or an insulating coating can be applied by an insulating resin.

[0060] ・Particle diameter

[0061] The particle diameter of the conductive particles 2 is appropriately selected depending on the use. In general, in order to suppress the increase in the conduction resistance and the occurrence of short circuit, it is preferable to be 1 μm or more and 30 μm or less, and if it is for a fine pitch use, it can be preferably 2 μm or more and less than 10 μm, and in the case where further fine pitch is required, the particle diameter can be less than 2 μm. As for the particle diameter of the conductive particles before being dispersed in the insulating resin layer, it can be measured by a general particle size distribution measuring device, and in addition, the average particle diameter can be obtained using the particle size distribution measuring device. As the measuring device, as one example, an image type FPIA-3000 (Malvern Panalytical) can be given. In this case, the number of samples in which the conductive particle diameter is measured is preferably 2000 or more, and more preferably 3000 or more. The particle diameter of the conductive particles in the anisotropic conductive film can be obtained from the observation of an electron microscope such as SEM. In this case, the number of samples in which the conductive particle diameter is measured is preferably 200 or more, and more preferably 1000 or more.

[0062] In addition, as for the deviation of the particle diameter, the CV value (coefficient of variation = standard deviation / average) of the particle diameter is preferably 20% or less. Since the deviation of the particle diameter is small, the heating and pressing conditions at the time of heat pressing can be taken with a larger margin.

[0063] The collection of the fine particles can also be regarded as one arrangement of the conductive particles. In this case, the diameter of the collection satisfies the CV value of 20% or less.

[0064] Further, in the case where the conductive particles on which the above-described insulating treatment is performed on the surface are used as the conductive particles, the particle diameter of the conductive particles in the present application refers to the particle diameter excluding the portion subjected to the insulating treatment.

[0065] <Arrangement of conductive particles>

[0066] Fig. 1A-1 is a pseudo-random regular arrangement 1A of the conductive particles 2 that the anisotropic conductive film 10A has, Figure 1B is an explanatory view of the method of making, and shows the state before the position of the y direction of the zigzag arrangement R is periodically changed.

[0067] The pseudo-random pattern configuration 1A can be made as follows. First, consider that the arrangement Rb in which the conductive particles 2 are arranged with a positive slope and the arrangement Rc in which the conductive particles 2 are arranged with a negative slope are zigzag-arranged R in which the arrangements Rb and Rc are repeatedly arranged at a predetermined interval in the y direction in the xy plane Figure 1B ), and then the zigzag-arranged R is arranged at a predetermined pitch in the x direction while periodically changing the position in the y direction of the zigzag-arranged R (Fig. 1A-1). In this case, the pattern of the conductive particles in which the zigzag-arranged R is arranged at a predetermined pitch in the x direction can also be considered in advance, and the position in the y direction of the zigzag-arranged R constituting the pattern of the conductive particles can be periodically changed.

[0068] More specifically, for example, in order to make the pseudo-random pattern configuration 1A shown in Fig. 1A-1, first consider the arrangement Rb in which three conductive particles 2 are arranged at an angle a with respect to the x direction and the arrangement Rc in which three conductive particles are arranged in a direction in which the arrangement direction is reversed with respect to the x direction. The arrangement direction of the conductive particles in the arrangement Rc becomes a direction at an angle -a with respect to the x direction Figure 1B ). The pitch L1 in the y direction of the conductive particles in the arrangement Rb and the pitch L2 in the y direction of the conductive particles in the arrangement Rc can be the same or different.

[0069] Next, consider the zigzag-arranged R in which the arrangement Rb and the arrangement Rc are repeatedly arranged at predetermined intervals L31, L32 in the y direction Figure 1B In the present application, the zigzag-arranged R can be repeatedly arranged with the arrangement Rb and the arrangement Rc, and it is not necessary to necessarily alternate them, but in the present embodiment, the arrangement Rb and the arrangement Rc are alternately arranged.

[0070] In addition, in the zigzag-arranged R, the offset Ld1, Ld2 in the x direction of the closest conductive particles of the adjacent arrangement Rb, arrangement Rc to each other can be appropriately set Figure 1B In the present embodiment, since the offset in the x direction of the arrangement Rb repeatedly arranged in the y direction or the offset in the x direction of the arrangement Rc is zero, Ld1 = Ld2 = Ld.

[0071] Next, assume that the zigzag-arranged R is arranged at a predetermined pitch pa in the x direction Figure 1B In this case, as shown by the curved line F of the double-dot chain line in Fig. 1A-1, the position in the y direction of the zigzag-arranged R is periodically changed (one period: R1, R2, R3, R4, R5, R6), and the pseudo-random pattern configuration 1A is obtained.

[0072] In this invention, there is no particular limitation on the number of conductive particles constituting the arrangement Rb and the number of conductive particles constituting the arrangement Rc. However, in order to facilitate the design of particle configuration, the arrangement Rb is preferably formed by 2 to 10, more preferably by 2 to 6, further preferably by 2 to 4, and especially by 2 to 3 conductive particles. The arrangement Rc is also preferably formed by 2 to 10, more preferably by 2 to 6, further preferably by 2 to 4, and especially by 2 to 3 conductive particles.

[0073] In this embodiment, since the angle between the arrangement Rb and the x-direction is α, and the angle between the arrangement Rc and the x-direction is -α, the arrangement directions of the arrangement Rb and the arrangement Rc are symmetrical with respect to the x-axis. In this invention, the absolute values ​​of the angles between the arrangement Rb and the x-direction and the arrangement Rc and the x-direction do not need to be strictly consistent. However, for ease of design, it is preferable that the difference between the absolute values ​​of the angles between the arrangement Rb and the x-direction and the absolute value of the angle between the arrangement Rb and the x-direction is less than 20%. This facilitates the creation of a pseudo-random pattern configuration where conductive particles do not overlap and are evenly distributed. On the other hand, by setting spacings L1, L2, pa, and L3, even if the above proportions exceed 20%, a pseudo-random pattern configuration with a uniform distribution of conductive particles can still be created. Furthermore, to ensure the irregularity of the appearance, the absolute value of angle α is preferably 5–85°, more preferably 10–80°, and even more preferably 15–75°.

[0074] Furthermore, in this embodiment, when the position of the zigzag arrangement R in the y direction is fixed along the x direction, the spacing pa in the x direction of the zigzag arrangement R is... Figure 1B The interval pa is fixed, but in this invention, the interval pa only needs to be regular and does not necessarily have to be fixed. For example, the intervals pa1 and pa2 can appear with a predetermined period. However, in order to facilitate the design of pseudo-random regular configurations, such as Figure 1B As shown, it is preferable to fix the spacing pa in the x-direction of the zigzag arrangement R when the position of the y-direction of the zigzag arrangement R along the x-direction is fixed.

[0075] In this invention, when the amplitude in the x-direction of the curved line forming the smallest repeating unit Ru (Fig. 1A-2) of the zigzag arrangement R, which includes adjacent arrangements Rb and Rc, is set to Lx, it is preferable that pa > Lx. Thus, when configured as a pseudo-random pattern, even if the position of the zigzag arrangement R in the y-direction is periodically changed, the conductive particles can be prevented from overlapping. On the other hand, for example, when it is desired to make the conductive particles denser in the x-direction, pa ≤ Lx can be made.

[0076] The pitch L1 of the conductive particles in the y direction of the arrangement Rb, the pitch L2 of the conductive particles in the y direction of the arrangement Rc, and the pitch pa of the zigzag-shaped arrangement R in the x direction when the positions in the y direction of the zigzag-shaped arrangement R are fixed can also be different from each other. From the viewpoint of making the deviation of the conductive particles uniform and the viewpoint of easily designing a pseudo-random regular arrangement, it is preferable that these be substantially equal. Here, by substantially equal is meant that the irregularity or uniformity of the pseudo-random regular arrangement obtained is substantially equal. Figure 1B The pitch pa of the zigzag-shaped arrangement R in the x direction when the positions in the y direction of the zigzag-shaped arrangement R are fixed can also be different from each other. From the viewpoint of making the deviation of the conductive particles uniform and the viewpoint of easily designing a pseudo-random regular arrangement, it is preferable that these be substantially equal. Here, by substantially equal is meant that the irregularity or uniformity of the pseudo-random regular arrangement obtained is substantially equal.

[0077] With regard to the interval L3 in the y direction when the arrangement Rb and the arrangement Rc are alternately arranged in the y direction, whether the interval L31 when the arrangement Rb is arranged on the arrangement Rc and the interval L32 when the arrangement Rc is arranged on the arrangement Rb are the same or different, a pseudo-random regular arrangement can be formed. From the viewpoint of making the deviation of the conductive particles uniform and the viewpoint of easily designing a pseudo-random regular arrangement, it is preferable that these intervals L31, L32 also have regularity, and it is particularly more preferable that these be fixed and equal. In addition, the intervals L31, L32 and the above-described pitches L1, L2 or the pitch pa can be the same or different, but it is more preferable that the intervals L31, L32 be fixed and equal, and that the interval L3 (L31, L32) and the above-described pitches L1, L2, pa be equal.

[0078] When the positions in the y direction of the zigzag-shaped arrangement R are periodically changed, the pattern of the periodic change is not particularly limited, but it is preferable that, for a curved line that forms the smallest repeating unit Ru of the zigzag-shaped arrangement R including the arrangement Rb and the arrangement Rc adjacent to each other, a curved line that is symmetric with respect to y = x for this curved line be formed and be taken as a curved line F0 that corresponds to the amount of one period in the x direction of the zigzag-shaped arrangement R, and the positions in the y direction of the zigzag-shaped arrangement R be changed along this curved line F0 (FIG. 1A-2). By this, the arrangement of the conductive particles in the repeating unit in the pseudo-random regular arrangement is made close to the particle arrangement that is symmetric with respect to y = x, and the uniformity of the arrangement of the conductive particles can be improved. Furthermore, when the positions in the y direction of the zigzag-shaped arrangement R are periodically changed, the periodic curved line that extends in the x axis direction is not limited to F as described later. As the repeating unit of the periodic curved line that extends in the x axis direction, when a curved line that is symmetric with the curved line that forms the smallest repeating unit Ru of the zigzag-shaped arrangement R or a curved line that is deformed from this is used, the axis of symmetry can also be made y ≠ x.

[0079] Further, in a case where the variation width of the y direction of the bending line F is Ly, it is preferable that Ly < L3 (L31, L32). Thus, the minimum repeating unit Ru of the pseudo-random regular arrangement can be set to a pattern of the conductive particles of a rectangle U including the length Lox of one cycle of the zigzag-shaped arrangement R in the x direction and the length L0y of the y direction of the minimum repeating unit Ru of the y direction of the zigzag-shaped arrangement R (the pattern of the conductive particles filled with a dark color in FIG. 1A-1 and FIG. 1A-2). Thus, in a case of manufacturing the anisotropic conductive film of the pseudo-random regular arrangement, it is easy to check whether the conductive particles of the film are arranged in the pseudo-random regular arrangement. In particular, it is preferable that the number of the conductive particles of the minimum repeating unit Ru of the zigzag-shaped arrangement R including the adjacent arrangement Rb and the arrangement Rc is equal to the number of the arrangements of one cycle of the zigzag-shaped arrangement R in the x direction. In this case, if the pitch LI = the pitch L2 = the interval L3 = the pitch pa, the pattern of the conductive particles of the minimum repeating unit of the pseudo-random regular arrangement can be a pattern symmetrical with respect to y = x. Thus, it is easy to check whether the conductive particles in the anisotropic conductive film are arranged in the pseudo-random regular arrangement, and thus is preferable.

[0080] (Modified method of the random regular arrangement)

[0081] Figure 4A In the pseudo-random regular arrangement IB illustrated, the arrangement Rb and the arrangement Rc each are composed of two conductive particles, the pitch LI = the pitch L2 = the interval L3 = the pitch pa, the offset amount Ld / pitch pa = 0.25, and the angle a = 60°.

[0082] As a method of creating the pseudo-random regular arrangement IB, first, consider that the zigzag-shaped arrangement R is arranged in the x direction at the pitch pa as illustrated in Figure 4B , and then consider that the bending line of the minimum repeating unit Ru of the zigzag-shaped arrangement R and the bending line F0 symmetrical with respect to y = x are formed, the zigzag-shaped arrangement R arranged at the pitch pa is sequentially moved in the y direction along the bending line F0, and this is repeated, thereby obtaining the pattern of the conductive particles illustrated in Figure 4A .

[0083] Thus, by setting the pitch LI = the pitch L2 = the interval L3 = the pitch pa and equalizing the number of the conductive particles of the minimum repeating unit Ru of the zigzag-shaped arrangement R to the number of the arrangements of one cycle of the zigzag-shaped arrangement R in the x direction, the pseudo-random regular arrangement of the conductive particles can be formed extremely easily.

[0084] Figure 5AIn the pseudo-random pattern arrangement 1C shown, the arrangement Rb and the arrangement Rc each are composed of two conductive particles, and are arranged at a pitch L1 = a pitch L2 = a pitch pa, an offset Ld / pitch pa = 0.5, and an angle a = 60°.

[0085] In the method of creating the pseudo-random pattern arrangement 1C, first, as in Figure 5B In the pattern shown in which the zigzag-shaped arrangement R is arranged in the x direction at a pitch pa, the position in the y direction of the zigzag-shaped arrangement R is changed while being moved in the y direction along the curved line F0 which is symmetrical to the curved line of the smallest repeating unit Ru of the zigzag-shaped arrangement R with respect to y = x, and this is repeated.

[0086] Further, Figure 5B The pattern of the conductive particles shown is a pattern in which a first region in which the arrangement Rb is arranged in the x direction at a pitch pa and a second region in which the arrangement Rc is arranged in the x direction at a pitch pa are alternately repeated in the y direction, and the extension of the axis of the arrangement Rb of the first region also becomes the extension of the arrangement axis of the second region (i.e., the conductive particles of the second region are positioned on the extension of the arrangement axis of the first region). However, in the present embodiment, the Figure 5A In the pseudo-random pattern arrangement shown in which the zigzag-shaped arrangement R is arranged in the x direction at a pitch pa while the position in the y direction of the zigzag-shaped arrangement R is changed, in the present embodiment, the extension of the arrangement axis of the first region in which the arrangement Rb is arranged in the x direction at a pitch pa does not become the extension of the arrangement axis of the second region in which the arrangement Rc is arranged in the x direction at a pitch pa.

[0087] In the present application, when the position in the y direction of the zigzag-shaped arrangement R is changed, the curved line F0 which is the reference is not limited to being symmetrical to the curved line of the smallest repeating unit Ru of the zigzag-shaped arrangement R with respect to y = x. For example, Figure 6 The pseudo-random pattern arrangement 1D shown is a pattern in which Figure 5B The pattern shown in which the zigzag-shaped arrangement R is arranged in the x direction at a pitch pa is changed while being moved in the y direction along the curved line F0 which is the same shape as Figure 4A the curved line of the smallest repeating unit Ru of the zigzag-shaped arrangement R.

[0088] Figure 7 The pseudo-random pattern arrangement 1E shown is a pattern in which Figure 4A In the pseudo-random pattern arrangement 1B shown, an offset Le in the x direction is provided between the arrangements Rb1 and Rb2 which repeat the zigzag-shaped arrangement R, or between the arrangements Rc1 and Rc2. In this arrangement, the offset in the x direction of the closest conductive particles of the adjacent arrangements Rb1 and Rc1 to each other is Ld, and the offset in the x direction of the closest conductive particles of the adjacent arrangements Rc1 and Rb2 to each other is zero.

[0089] Figure 8A The pseudo-random type regular arrangement 1F shown is: to Figure 7 The pseudo-random type regular arrangement 1E shown further increases the offset amount Le in the x direction of the arrangement Rbl and the arrangement Rb2. This can make the direction in which the zigzag-shaped arrangement R extends inclined with respect to the y axis according to the size of the offset amount Le.

[0090] Further, in the present application, the xy coordinates are not limited to orthogonal coordinates. For example, Figure 8B The above-mentioned Figure 8A The pseudo-random type regular arrangement 1F shown. For the convenience of design, orthogonal coordinates are preferably used.

[0091] <Number density of conductive particles>

[0092] The number density of the conductive particles in the anisotropic conductive film of the present application can be determined according to the shape, size, arrangement pitch, etc. of the terminals of the electronic components to be connected by the anisotropic conductive film. Generally, the number density of the conductive particles is preferably changed according to the combination or use of the electronic components to be connected, and thus is not particularly limited, but the lower limit in practical use is 30 pieces / mm 2 or more, and the upper limit is 500000 pieces / mm 2 or more, and the upper limit is 500000 pieces / mm 2 or more. If the number density is low, cost reduction effects can be expected. Further, the upper limit in practical use is 500000 pieces / mm 2 or more, and the upper limit is 500000 pieces / mm 2 or more, and the upper limit is 500000 pieces / mm 2 or more, and the upper limit is 500000 pieces / mm 2 or more. In the case of a fine pitch use, according to the degree of the fine pitch, it can be, for example, 6000 to 35000 pieces / mm 2 or more, and the upper limit is 500000 pieces / mm 2 or more, and the upper limit is 500000 pieces / mm 2 or more, and the upper limit is 500000 pieces / mm 2 or more, and the upper limit is 500000 pieces / mm 2 or more. Further, in the case where the average particle diameter of the conductive particles is 10 μm or more, it is preferably in the range of 50 to 2000 pieces / mm 2 .

[0093] As the measurement region at the time of measuring the number density, it is preferable to arbitrarily set a plurality of positions of a rectangular region of 100 μm or more in length (preferably 5 positions or more, and more preferably 10 positions or more), and make the total area of the measurement regions 2 mm 2The length of side or the total area of the rectangular region is adjusted according to the average particle diameter. The size or the number of the respective measurement regions is appropriately adjusted according to the state of the number density. For example, there are tens of conductive particles in one rectangular region. As a more specific example, in the case of an anisotropic conductive film in which the number density of the conductive particles is relatively large in a fine pitch application, the number density at 200 positions (2 mm 2 ) in an area of 100 μm x 100 μm is measured using an observation image of a metallographic microscope, an electron microscope (for example, SEM or TEM), or the like, and the average thereof is obtained. The number density can be measured using a three-dimensional surface measurement device or can be obtained by measuring an observation image with image analysis software (for example, WinROOF manufactured by Shintaku Corporation, "A-KUN" (registered trademark) manufactured by Asahi Kasei Engineering Corporation, or the like).

[0094] In addition, regarding the number density of the conductive particles, from the viewpoint of reducing the on-resistance, it is preferable that the area occupancy of the conductive particles calculated by the following formula is 0.3% or more. On the other hand, from the viewpoint of suppressing the pushing force required for the pressing jig at the time of connection, the area occupancy can be 40% or less, preferably 35% or less, and more preferably 30% or less.

[0095] Area occupancy of conductive particles (%) = [number density of conductive particles in plan view] x [average of areas of two conductive particles in plan view] x 100

[0096] Position in film thickness direction of conductive particles

[0097] It is preferable that the position in the film thickness direction of the conductive particles 2 is uniform. For example, as shown in FIG. 2, it is possible to make the embedding amount Lb of the conductive particles 2 in the film thickness direction uniform. Thereby, the capturability of the conductive particles 2 at the terminal is easily stabilized. On the other hand, in the present application, the conductive particles 2 can be exposed from the insulating resin layer 3 or can be completely embedded. Figure 2

[0098] Here, the embedding amount Lb is the distance between the tangent plane of the central portion between the adjacent conductive particles and the deepest portion of the conductive particles 2 in the surface of the insulating resin layer 3 in which the conductive particles 2 are embedded (among the surface and the back surface of the insulating resin layer 3, the surface on which the conductive particles 2 are exposed, or the surface closer to the conductive particles 2 in the case where the conductive particles 2 are completely embedded in the insulating resin layer 3).

[0099] Further, the embedding amount Lb can be obtained by observing a part of the film cross section of the anisotropic conductive film with an SEM image. In this case, an area of 30 mm 2 ​The above area is preferably measured for a total of 50 or more, and more preferably 200 or more, of the conductive particles to obtain an average thereof.

[0100] <Embedding rate>

[0101] In a case where a ratio of the embedding amount Lb to the average particle diameter D of the conductive particles 2 is set as an embedding rate (Lb / D), the embedding rate is preferably 30% or more and 105% or less. By making the embedding rate (Lb / D) 30% or more, the conductive particles 2 are maintained at a predetermined position by the insulating resin layer 3, and by making the embedding rate (Lb / D) 105% or less, the amount of resin of the insulating resin layer that acts in a manner that the conductive particles between the terminals flow unnecessarily at the time of anisotropic conductive connection can be reduced.

[0102] <Insulating resin layer>

[0103] In the anisotropic conductive film of the present application, the insulating resin layer 3 can be formed using a curable resin composition formed of a polymerizable compound and a polymerization initiator, like the insulating resin layer of the anisotropic conductive film described in Japanese Patent No. 6187665. In this case, as the polymerization initiator, either a thermal polymerization initiator or a photopolymerization initiator can be used, or both can be used. For example, a cationic polymerization initiator is used as the thermal polymerization initiator, an epoxy resin is used as the thermal polymerizable compound, a photoradical polymerization initiator is used as the photopolymerization initiator, and an acrylate compound is used as the photopolymerizable compound. As the thermal polymerization initiator, a thermal anionic polymerization initiator can also be used. As the thermal anionic polymerization initiator, a microcapsule type latent curing agent in which an imidazole modifier is used as a core and polyurethane is coated on the surface thereof is preferably used.

[0104] <Minimum melt viscosity of insulating resin layer>

[0105] The minimum melt viscosity of the insulating resin layer 3 is not particularly limited, but can be 1000 Pa・s or more, and like the minimum melt viscosity of the insulating resin layer of the anisotropic conductive film described in Japanese Patent No. 6187665, is preferably 1500 Pa・s or more, more preferably 2000 Pa・s or more, further preferably 3000 to 15000 Pa・s, and particularly preferably 3000 to 10000 Pa・s. As one example, the minimum melt viscosity can be obtained using a rotational rheometer (manufactured by TA Instruments, Inc.) by holding it fixed at a measurement pressure of 5 g and using a measuring plate with a diameter of 8 mm, and more specifically, by setting the temperature increase rate to 10°C / min, the measurement frequency to 10 Hz, and the load variation with respect to the measuring plate to 5 g in a temperature range of 30 to 200°C. Furthermore, the minimum melt viscosity can be adjusted by changing the kind or the blending amount of the fine solid contained as a melt viscosity adjusting agent, the adjustment conditions of the resin composition, or the like.

[0106] <Low viscosity resin layer>

[0107] The low viscosity resin layer 4 is a resin layer having a lower minimum melt viscosity in a range of 30 to 200°C than the insulating resin layer 3. In the present application, the low viscosity resin layer 4 is provided as needed, but by laminating the low viscosity resin layer 4 to the insulating resin layer 3, in the case of thermocompression bonding electronic components facing each other via the anisotropic conductive film 10A, the space formed by the electrodes or the bumps of the electronic components is filled with the low viscosity resin layer 4, and the adhesion of the electronic components to each other can be improved.

[0108] In addition, the greater the difference between the minimum melt viscosity of the insulating resin layer 3 and the minimum melt viscosity of the low viscosity resin layer 4, the more the space between the electronic components connected via the anisotropic conductive film 10A is filled with the low viscosity resin layer 4, and the adhesion of the electronic components to each other is easily improved. In addition, the greater the difference, the relatively smaller the amount of movement of the insulating resin layer 3 at the time of thermocompression bonding of the insulating resin layer 3 holding the conductive particles 2 than the low viscosity resin layer 4, and the capture of the conductive particles 2 at the terminals is easily improved.

[0109] The minimum melt viscosity ratio of the insulating resin layer 3 to the low viscosity resin layer 4 depends on the thickness ratio of the insulating resin layer 3 to the low viscosity resin layer 4, but is preferably 2 or more, more preferably 5 or more, and further preferably 8 or more. On the other hand, if the ratio is too large, resin extrusion or blocking can occur when a long anisotropic conductive film is made into a roll, and thus is preferably 15 or less in practical use. More specifically, the preferable minimum melt viscosity of the low viscosity resin layer 4 satisfies the minimum melt viscosity ratio of the insulating resin layer described above, and is preferably 3000 Pa・s or less, more preferably 2000 Pa・s or less, and further preferably 100 to 2000 Pa・s.

[0110] Further, the low-viscosity resin layer 4 can be formed by adjusting the viscosity in the same resin composition as the insulating resin layer 3. Alternatively, it can be formed from another resin composition.

[0111] Thickness of Insulating Resin Layer and Low-Viscosity Resin Layer

[0112] The thickness of the insulating resin layer 3 is preferably 0.3 times or more, more preferably 0.6 times or more, further preferably 0.8 times or more, and particularly preferably 1 time or more, the average particle diameter D of the conductive particles 2, in order to stably press the conductive particles 2 into the insulating resin layer 3 in the manufacturing process of the anisotropic conductive film described later. The upper limit of the thickness of the insulating resin layer 3 can be determined depending on the terminal shape, terminal thickness, arrangement pitch, and the like of the electronic component to be connected, but if the thickness is too thick, the conductive particles 2 are easily affected by unnecessary resin flow at the time of connection, and thus it is preferably 20 times or less, and more preferably 15 times or less, the average particle diameter D of the conductive particles 2.

[0113] In the present application, the low-viscosity resin layer 4 is provided as needed, but in the case where the low-viscosity resin layer 4 is provided, as the lower limit of the thickness thereof, it is preferably 0.2 times or more, and more preferably 1 time or more, the average particle diameter D of the conductive particles 2. Further, as the upper limit of the thickness of the low-viscosity resin layer 4, if it is too thick, the lamination difficulty with the insulating resin layer 3 increases, and thus it is preferably 50 times or less, more preferably 15 times or less, and further preferably 8 times or less, the average particle diameter D of the conductive particles 2.

[0114] Further, from the viewpoint of suppressing unnecessary flow of the conductive particles 2 at the time of connection of the electronic component, the viewpoint of suppressing extrusion or blocking of the resin at the time of making the anisotropic conductive film into a roll, the viewpoint of lengthening the film length per unit weight of the anisotropic conductive film, and the like, the total thickness of the insulating resin layer 3 and the low-viscosity resin layer 4 is preferably thin. However, if it is too thin, the processability of the anisotropic conductive film deteriorates. Further, it is difficult to attach the anisotropic conductive film to the electronic component, it can not be possible to obtain the adhesion required in the temporary press bonding at the time of connecting the electronic components, and it can not be possible to obtain the required adhesion in the formal press bonding due to the lack of the amount of resin. Therefore, the total thickness is preferably 0.6 times or more, more preferably 0.8 times or more, further preferably 1 time or more, and particularly preferably 1.2 times or more, the average particle diameter D of the conductive particles 2.

[0115] The thickness ratio of the insulating resin layer 3 and the low-viscosity resin layer 4 can be appropriately adjusted depending on the combination of the electronic components to be connected, the required performance, and the like. These thicknesses can be measured with a commercially available digital thickness gauge or the like. The resolution of the digital thickness gauge is preferably 0.1 μm or less.

[0116] In the case where at least one of the insulating resin layer and the low-viscosity resin layer is multi-layered (for example, as shown in Figure 3B When the anisotropic conductive film is three-layered by sandwiching the insulating resin layer 3 between the low-viscosity resin layers 4A and 4B, the relationship between the total thickness of the low-viscosity resin layers and the insulating resin layer is preferably the above-described relationship.

[0117] <Anisotropic conductive film roll>

[0118] The anisotropic conductive film of the present application can be in the form of a roll. The length of the roll is not particularly limited, but from the viewpoint of workability of the product, it is preferably 5,000 m or less, more preferably 1,000 m or less, and even more preferably 500 m or less. On the other hand, from the viewpoint of mass productivity of the roll, it is preferably 5 m or more. The width of the film is not particularly limited, but from the viewpoint of miniaturization of the mounting object, it is required to be narrow. On the other hand, from the viewpoint of the use method of batch anisotropic conductive connection of a plurality of members or batch anisotropic conductive connection followed by cutting to a certain size, it is required to be large in area, and thus there is also a demand for a roll with a wide width.

[0119] <Method for manufacturing anisotropic conductive film>

[0120] The method for manufacturing the anisotropic conductive film of the present application is not particularly limited, and for example, a transfer mold for arranging conductive particles in a predetermined arrangement is manufactured, the concave portions of the transfer mold are filled with the conductive particles, an insulating resin layer formed on a release film is overlaid thereon and pressure is applied, the conductive particles are pressed into the insulating resin layer, and thus the conductive particles are transferred to the insulating resin layer, or further, a low-viscosity resin layer is laminated on the conductive particles or on the surface opposite to the surface on which the conductive particles are transferred, and thus the anisotropic conductive film is manufactured.

[0121] Alternatively, after the concave portions of the transfer mold are filled with the conductive particles, an insulating resin layer is overlaid thereon, the conductive particles are not pressed into the insulating resin layer in the transfer mold, but are transferred from the transfer mold to the surface of the insulating resin layer, the conductive particles on the insulating resin layer after the transfer are pressed into the insulating resin layer, and thus the anisotropic conductive film is manufactured.

[0122] Further, as the transfer mold, in addition to the transfer mold in which the concave portions are filled with the conductive particles, the top surface of the convex portions can be provided with a micro-adhesive to adhere the conductive particles to the top surface. These transfer molds can be manufactured using known techniques such as machining, photolithography, and printing.

[0123] In addition, as a method of arranging the conductive particles in a predetermined arrangement, instead of the method using the transfer mold, a method of filling the conductive particles in a through hole provided in a predetermined arrangement (a method of filling the conductive particles in a through hole and laminating insulating resin films on both surfaces thereof), a method of directly scattering the conductive particles on a film, a method of stretching a film in which the conductive particles are densely arranged, and the like can be used.

[0124] <Method of connecting electronic components using anisotropic conductive film>

[0125] As a method of connecting electronic components using the anisotropic conductive film of the present application, for example, one electronic component is carried on a stage, and the other electronic component is carried thereon with the anisotropic conductive film interposed therebetween, and the terminals of both electronic components are anisotropically conductively connected to each other by heating and pressing with a press tool, thereby manufacturing a connection structure. In this case, the electronic component carried on the stage is an IC chip, an IC module, an FPC, a glass substrate, a plastic substrate, a rigid substrate, a ceramic substrate, or the like, and the electronic component subjected to heating and pressing with the press tool is an FPC, a semiconductor element (an IC chip, an IC module, an LED element (a submillimeter LED or a micro LED, or the like), a sensor component, a battery element, or the like, which is a first electronic component. As a more detailed method, the anisotropic conductive film is temporarily attached to the second electronic component such as various substrates and the like and is temporarily press-bonded, the first electronic component such as an IC chip is attached to the temporarily press-bonded anisotropic conductive film, and heat press-bonding is performed to anisotropically conductively connect, thereby manufacturing a connection structure. In addition, the connection structure can be manufactured by temporarily attaching the anisotropic conductive film to the first electronic component instead of the second electronic component. In addition, the connection method is not limited to heat press-bonding, and press-bonding using light curing or press-bonding using both heat and light, or the like can be performed. In recent years, the types of these electronic components have diversified, and are not limited to these press-bonding methods. In addition, the method of manufacturing the connection structure is not limited to these methods, and the best method is selected in preference to the electronic components.

[0126] The anisotropic conductive film of the present invention is significant when at least one of the first and second electronic components is made of a material prone to thermal expansion, such as an FPC or a plastic substrate. It is particularly effective when the terminal array is fan-out. Furthermore, it is applicable even when the long side of the terminals is not tilted relative to the terminal arrangement direction, or when the terminal arrangement directions on each side of the component differ, such as with peripherally arranged terminals. Regardless of whether the terminal shape is rectangular or circular, the conductive particles are uniformly distributed across each terminal, enabling reliable connection, suppressing short circuits, and facilitating indentation inspection. Therefore, the anisotropic conductive film of the present invention can be used universally regardless of the shape or arrangement of the connected terminal array. The present invention includes a method for manufacturing a connection structure that uses the anisotropic conductive film of the present invention to anisotropically conductively connect the terminals of the first electronic component and the terminals of the second electronic component, or a connection structure that anisotropically conductively connects the first electronic component and the second electronic component through the anisotropic conductive film of the present invention.

[0127] (Example)

[0128] The present invention will be specifically described below through examples.

[0129] (Example 1)

[0130] As a configuration of conductive particles in anisotropic conductive films, simulations were performed. Figure 4A The pseudo-random pattern configuration is shown. In this case, the diameter of conductive particle 2 is 3μm, L1=L2=L3=pa=8μm, and the number density of conductive particle 2 is 16000 particles / mm. 2 .

[0131] exist Figure 9 The conductive particle pattern in this case is shown.

[0132] (Comparative Example 1)

[0133] As a configuration of conductive particles in anisotropic conductive films, simulations were performed. Figure 4B The configuration is as shown. In this case, the diameter of conductive particle 2 is 3 μm, L1 = L2 = L3 = pa = 8 μm, and the number density of conductive particle 2 is 16000 particles / mm². 2 .

[0134] exist Figure 10 The conductive particle pattern in this case is shown.

[0135] (Comparative Example 2)

[0136] The arrangement of the conductive particles in the anisotropic conductive film was simulated as a hexagonal lattice, and the angle γ of the lattice axis with respect to the x direction was 15°, and the number density was 16000 pieces / mm 2 .

[0137] (Comparative Example 3)

[0138] The arrangement of the conductive particles in the anisotropic conductive film was simulated as a hexagonal lattice, and the angle γ of the lattice axis with respect to the x direction was 0°, and the number density was 16000 pieces / mm 2 .

[0139] (Evaluation)

[0140] By simulation, (i) the minimum number of captured conductive particles at each terminal and (ii) the uniformity of the captured conductive particles up and down or left and right in the terminal column were investigated in the case where the anisotropic conductive film of Example 1 and Comparative Examples 1 to 3 was connected to the terminal column of Case 1 to 4 of Table 1.

[0141] Here, on the basis of evaluating pseudo-randomness, (i) the minimum number of captured conductive particles and (ii) the uniformity of the captured conductive particles up and down or left and right in the terminal column were evaluated according to the following criteria.

[0142] (i) Minimum number of captured conductive particles

[0143] OK: 4 or more

[0144] NG: 3 or less

[0145] (ii) Uniformity

[0146] Uniform: The case where the distribution patterns of the captured conductive particles on the terminals at the distance symmetrical up and down or left and right in the terminal column looked the same as each other;

[0147] Non-uniform: The case where the distribution patterns of the captured conductive particles on the terminals at the distance symmetrical up and down or left and right in the terminal column looked different from each other.

[0148] The results are shown in Table 2.

[0149] [Table 1]

[0150] Case 1 2 3 4 Shape Straight Straight Straight Straight Wiring length (pm) 100 4 100 4 Wiring width (pm) 4 100 4 100 Fan-out angle (°) 0 0 -10～10 -10～10 Spacing between wirings (pm) 20 20 20 20

[0151] [Table 2]

[0152]

[0153]

[0154] It is confirmed from Table 2 that the anisotropic conductive film according to the embodiment can obtain the capturing property even if the orientation with respect to the terminal differs by 90°, and the captured particles are uniform in the up-down and left-right directions for the fan-out terminal.

[0155] In addition, by comparing Figure 9 and Figure 10 it is seen that the pattern of the embodiment is excellent in appearance irregularity.

[0156] (Explanation of Reference Numerals)

[0157] 1A, 1B, 1C, 1D, 1E, 1F, 1B1 Pseudo-random regular arrangement; 2 Conductive particles; 3 Insulating resin layer, insulating film; 3h Through-hole; 4, 4A, 4B Low-viscosity resin layer; 10A, 10B, 10C Anisotropic conductive film; 20 Terminal; F Bending line; F0 Bending line symmetrical to y = x with respect to the bending line of the smallest repeating unit Ru of the zigzag arrangement R; pa Pitch in the x direction of the zigzag arrangement R when the position in the y direction of the zigzag arrangement R is fixed; R Zigzag arrangement; Rb, Rc Arrangement; Ru Smallest repeating unit of the zigzag arrangement R; U Smallest repeating unit of the pseudo-random regular arrangement; a Angle formed by the arrangement Rb and the x direction.

Claims

1. An anisotropic conductive film, wherein conductive particles are disposed in an insulating resin layer, and in the xy plane viewed from above, an arrangement Rb of conductive particles with a positive slope and an arrangement Rc of conductive particles with a negative slope are arranged in a zigzag pattern R at predetermined intervals in the y direction, and while periodically changing the position in the y direction, they are arranged at predetermined intervals in the x direction, and when the position of the zigzag pattern R arranged along the x direction is fixed in the y direction, the spacing pa of the zigzag pattern R in the x direction is fixed.

2. An anisotropic conductive film, wherein conductive particles are disposed in an insulating resin layer, and in the xy plane viewed from above, an arrangement Rb of conductive particles with a positive slope and an arrangement Rc of conductive particles with a negative slope are arranged in a zigzag pattern R at predetermined intervals in the y direction, and while periodically changing their positions in the y direction, they are arranged at predetermined intervals in the x direction, and the interval L3 in the y direction between the arrangement Rb and the arrangement Rc is fixed.

3. An anisotropic conductive film, wherein conductive particles are disposed in an insulating resin layer, and in the xy plane viewed from above, an arrangement Rb of conductive particles with a positive slope and an arrangement Rc of conductive particles with a negative slope are arranged in a zigzag pattern R at predetermined intervals in the y direction, and while periodically changing their position in the y direction, they are arranged at predetermined intervals in the x direction, wherein the number of conductive particles constituting the smallest repeating unit in the zigzag pattern R is equal to the number of arrangements in the x direction of the zigzag pattern R corresponding to one period of position change in the y direction of the zigzag pattern R.

4. An anisotropic conductive film, wherein conductive particles are disposed in an insulating resin layer, and in the xy plane viewed from above, an arrangement Rb of conductive particles with a positive slope and an arrangement Rc of conductive particles with a negative slope are arranged in a zigzag pattern R at predetermined intervals in the y direction, and while periodically changing the position in the y direction, they are arranged at predetermined intervals in the x direction. The conductive particles constituting the smallest repeating unit in the zigzag pattern R are arranged in a configuration symmetrical with respect to y = x, while changing the position in the y direction by an amount of one period.

5. An anisotropic conductive film, wherein conductive particles are disposed in an insulating resin layer, and in the xy plane viewed from above, an arrangement Rb of conductive particles with a positive slope and an arrangement Rc of conductive particles with a negative slope are arranged in a zigzag pattern R at predetermined intervals in the y direction, and while periodically changing their positions in the y direction, they are arranged at predetermined intervals in the x direction, and the extension line of the arrangement axis of the first region where the arrangement Rb is arranged at a interval pa in the x direction does not become the extension line of the arrangement axis of the second region where the arrangement Rc is arranged at a interval pa in the x direction.

6. An anisotropic conductive film, wherein conductive particles are disposed in an insulating resin layer, and in the xy plane viewed from above, an arrangement Rb of conductive particles with a positive slope and an arrangement Rc of conductive particles with a negative slope are arranged in a zigzag pattern R at predetermined intervals in the y direction, and while periodically changing their position in the y direction, they are arranged at predetermined intervals in the x direction, and the repeated zigzag pattern Rs are offset from each other in the x direction.

7. An anisotropic conductive film, wherein conductive particles are disposed in an insulating resin layer, and in the xy plane viewed from above, an arrangement Rb in which the conductive particles are arranged with a positive slope and an arrangement Rc in which the conductive particles are arranged with a negative slope are arranged in a zigzag pattern R at predetermined intervals in the y direction, and while periodically changing their positions in the y direction, they are arranged at predetermined intervals in the x direction, wherein the x-direction spacing pa of the zigzag arrangement R, the y-direction spacing L1 of the conductive particles in the arrangement Rb, the y-direction spacing L2 of the conductive particles in the arrangement Rc, and the y-direction interval L3 of the arrangement Rb and the arrangement Rc are equal.

8. An anisotropic conductive film, wherein conductive particles are disposed in an insulating resin layer, and in the xy plane viewed from above, an arrangement Rb of conductive particles with a positive slope and an arrangement Rc of conductive particles with a negative slope are arranged in a zigzag pattern R at predetermined intervals in the y direction, and arranged at predetermined intervals in the x direction while periodically changing their positions in the y direction, wherein the insulating resin layer is formed using a curable resin composition formed from a polymerizable compound and a polymerization initiator.

9. The anisotropic conductive film according to any one of claims 1 to 8, wherein, The arrangement Rc is arranged along the direction that reverses the arrangement direction of the arrangement Rb relative to the x-direction.

10. The anisotropic conductive film as described in claim 2, wherein, The y-direction spacing L1 of the conductive particles in arrangement Rb is equal to the y-direction spacing L2 and the interval L3 of the conductive particles in arrangement Rc.

11. The anisotropic conductive film as described in claim 2, wherein, The spacing pa in the x-direction of the zigzag arrangement R, the spacing L1 in the y-direction of the conductive particles in the arrangement Rb, the spacing L2 in the y-direction of the conductive particles in the arrangement Rc, and the interval L3 are all equal.

12. The anisotropic conductive film as described in claim 2, wherein, The width Ly of the positional change in the y-direction of the zigzag arrangement R is less than the interval L3.

13. The anisotropic conductive film as described in claim 1, wherein, The amplitude Lx in the x-direction of the zigzag arrangement R is less than the spacing pa.

14. A method for manufacturing a connection structure, comprising anisotropically conductively connecting the terminals of a first electronic component and the terminals of a second electronic component using an anisotropic conductive film as described in any one of claims 1 to 13.

15. A connection structure, wherein, The first electronic component and the second electronic component are anisotropically electrically connected via an anisotropic conductive film as described in any one of claims 1 to 13.

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