Anisotropic Conductive Film

Abstract

To provide an anisotropic electroconductive film with which sufficient conductive particles can be held by the terminals of a terminal array to ensure a good conductive state regardless of whether the axes of the terminals are aligned in the same direction or are arranged in a radial fan-out type, and with which the conductive particle capture state at each terminal can be made uniform and the occurrence of a short circuit can be prevented even if a fine-pitched terminal is connected.SOLUTION: An anisotropic electroconductive film 10A includes conductive particles 2 disposed in an insulative resin layer 3. In an xy plane showing a plan view of the anisotropic electroconductive film 10A, zigzag sequences R are arranged at a predetermined pitch in an x direction while the positions in a y direction are periodically changed, each zigzag sequence R consisting of a sequence Rb where the conductive particles 2 are arranged in a positive orientation and a sequence Rc where the conductive particles 2 are arranged in a negative orientation which are repeatedly provided in the y direction with predetermined intervals therebetween. Thus, a pseudo-random regular arrangement 1A of the conductive particles is achieved.SELECTED DRAWING: Figure 1A-1

Description

Technical Field

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

Background Art

[0002] Since plastic substrates and FPCs (Flexible Printed Circuits) are frequently used because of the requirements for weight reduction and flexibility in substrates for mounting electronic components such as IC chips, the pitch of terminals in electronic components such as IC chips has been refined, and the thermal expansion of plastic substrates and FPCs may cause problems during the mounting of electronic components. Therefore, in order to ensure the connection of electronic components even when the positions of the terminals are displaced due to temperature fluctuations during the mounting of electronic components, instead of arranging each terminal constituting the terminal row of the electronic component in parallel in the same direction as before, the terminals are arranged in parallel radially (so-called fan-out wiring) (Patent Document 1).

[0003] In addition to the fan-out arrangement, in LED elements (so-called micro-LEDs, mini-LEDs), etc., a unique electrode arrangement different from the conventional one is required.

[0004] On the other hand, for the mounting of electronic components, an anisotropic conductive film in which conductive particles are dispersed in an insulating resin layer is widely used. In the connection of electronic components using an anisotropic conductive film, in order to ensure that the conductive particles of the anisotropic conductive film are stably captured by the terminals of the electronic components even when the pitch of the terminals of the electronic components is refined, it has been proposed to arrange the conductive particles in a lattice such as a hexagonal lattice in the anisotropic conductive film and incline the array axis with respect to the longitudinal direction of the terminals (Patent Document 2). In addition, as the particle arrangement of the anisotropic conductive film, the conductive particles are arranged in a first direction obliquely with respect to the longitudinal direction of the film, a plurality of particle rows in the first direction are arranged in parallel in a second direction different from the arrangement direction, the particle row in the first direction is not made into a single straight line, and the particle row has a width of less than 2.5 times the particle diameter of the conductive particles (Patent Document 3), or a unit in which the conductive particles are arranged at a predetermined interval is repeatedly arranged (Patent Documents 4 and 5), etc. have also been proposed.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, when performing, for example, FOG (Film On Glass) connection using an anisotropic conductive film, as shown in FIG. 11A, each terminal 20 to be connected is arranged in parallel in the same direction, the conductive particles 2 of the anisotropic conductive film are arranged in a hexagonal lattice, and even if the array axis is inclined at an angle δ with respect to the longitudinal direction of the terminal 20 (the direction perpendicular to the array direction x), resin flow in the arrow direction occurs between the terminals due to thermocompression bonding during connection. Therefore, depending on the conditions, as shown in FIG. 11B after connection, a dense region A of the conductive particles 2 occurs between the terminals, which causes a short circuit.

[0007] Also, as shown in Fig. 12A, when attempting to connect a fan-out type terminal row using an anisotropic conductive film in which conductive particles 2 are arranged in a hexagonal lattice with the array axis of the hexagonal lattice inclined (inclination angle γ) in the longitudinal direction of the film, since the fan-out angle β (i.e., the angle of the longitudinal direction of terminal 20 with respect to the arrangement direction x of the terminals) is slightly different for each terminal overall, the number and distribution state of the conductive particles 2 captured by one terminal are different on the right and left sides of the fan-out type terminal row, and the appearance of the indentation after connection is also different. In addition, in the arrangement of the conductive particles shown in the same figure, in the temporarily attached state of the terminal row before thermocompression bonding, since the conductive particles 2 are captured only at the edge of the terminal on terminal 20a on the left side of the paper surface, there is concern that poor conduction may occur after connection.

[0008] Also, when connecting a terminal row using an anisotropic conductive film in which conductive particles are arranged in a hexagonal lattice, the number of columns of conductive particles related to capture in the array axis perpendicular to the arrangement direction x of the terminals is different for each terminal, the number of captured conductive particles captured by one terminal varies greatly, and the distribution of the number of captures may be bimodal. This can occur not only in a hexagonal lattice but also in a square lattice or a rhombic lattice. For example, as shown in Fig. 12B, the conductive particles 2 captured by terminal 20b belong to one array axis y1 perpendicular to the arrangement direction x of the terminals, while in terminal 20c, the conductive particles 2 belonging to two array axes y2, y3 are captured. Such a phenomenon becomes more prominent when the terminal row is not of the fan-out type but the axes of each terminal are in the same direction, as shown in Fig. 12C. There are a considerable number of terminals 20b related to connection with one array axis y1 and terminals 20c related to connection with two array axes y2, y3, respectively, and the variation in the number of conductive particles captured by one terminal becomes large. Therefore, when graphing the number of conductive particles captured by one terminal and the appearance frequency of the terminals with that number of captures, there may be multiple peaks. That is, due to multiple factors such as terminal width, terminal pitch, particle diameter, and particle spacing, for example, a bimodal peak may appear. Although the occurrence of a bimodal peak does not immediately cause practical problems, it is easier to control the number of captured conductive particles in a unimodal peak.

[0009] Also, due to thermocompression bonding during connection, the spacing between conductive particles on the terminals expands more in the short direction than in the longitudinal direction of the terminals. The conductive particles on the terminals are pushed out between the terminals, and the conductive particles existing between the terminals, including the pushed-out conductive particles, move due to the resin flow during thermocompression bonding. Therefore, the distribution of conductive particles with respect to the terminals is different on the right and left sides of the terminal row, and when a dense portion of conductive particles is formed between the terminals, there is a problem that short circuits are likely to occur at that portion.

[0010] The phenomenon that the conductive particles between the terminals cause a short circuit due to the resin flow during thermocompression bonding occurs not only when the terminal row is of a radial fan-out type but also when straight terminals are arranged straight in the same direction in parallel (straight parallel arrangement). 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 due to the resin flow. However, if the use of the photocurable resin suppresses the resin flow of the conductive particles by making the photocured resin mixed in the resin layer that cures during connection, there is a concern that the pressure applied to the conductive particles during thermocompression bonding may become insufficient, resulting in poor connection 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 containing a filler in the insulating resin layer, etc., to suppress the resin flow while applying sufficient pressure during thermocompression bonding. However, it is required to make short circuits less likely to occur for both the straight parallel arrangement type terminal row and the fan-out type terminal row. This is because it is difficult to completely prevent short circuits of the conductive particles only by the curability and viscosity of the insulating resin that holds the conductive particles. In particular, when continuously manufacturing a large number of connection structures in a production line or the like responsible for the connection process, there is a concern that short circuits cannot be completely prevented when irregular resin flow or alignment deviation occurs. Furthermore, as the terminal layout and the materials of electronic components become more diverse, it becomes even more difficult to achieve both ensuring conduction and preventing short circuits in any terminal layout and materials of electronic components.

[0011] In order to stabilize the number of conductive particles captured at each terminal and suppress short circuits due to resin flow, as described in Patent Document 3, if the first particle row of conductive particles has a width equal to or greater than the particle diameter instead of being linear, it becomes impossible to strictly control the particle arrangement. As a result, it becomes difficult to keep the number of conductive particles captured at each terminal within a predetermined range. Also in this case, if irregular resin flow or alignment deviation occurs in a production line for continuously manufacturing the connection structure, etc., it becomes even more difficult to keep the number of conductive particles captured within a predetermined range. This level of difficulty increases as the number of connection structures to be continuously manufactured increases.

[0012] Further, even if units of conductive particles are repeatedly arranged as described in Patent Documents 4 and 5, it is difficult to make the distribution of conductive particles equal on the right and left sides of the terminal row on the fan-out side. In particular, this tendency becomes stronger as the terminal length becomes shorter, and it becomes difficult to reduce the variation in the number of conductive particles captured at each terminal.

[0013] In view of the above problems, an object of the present invention is to make the state of capture of conductive particles at the terminals after connection, which can be confirmed by indentation or the like, uniform regardless of the material of the electronic component, whether the axes of the terminals in the terminal row to be connected are parallel in the same direction and the terminal row is straight or in a radial fan-out type, and to ensure that sufficient conductive particles are sandwiched at each terminal to secure a good conduction state. Further, it is an object to prevent the occurrence of short circuits even when connecting fine-pitch terminals.

Means for Solving the Problems

[0014] The inventor of the present invention conceived that when the arrangement of conductive particles in the anisotropic conductive film is such that a zigzag arrangement R of conductive particles extending in the y direction in the xy plane is arranged at a predetermined pitch in the x direction while periodically changing the position in the y direction, the conductive particles form a pseudo-random type regular arrangement, and thus completed the present invention by which the above problems can be solved.

[0015] That is, the present invention is an anisotropic conductive film in which conductive particles are arranged in an insulating resin layer. In the xy plane when the anisotropic conductive film is viewed in plan view, an array Rb in which the conductive particles are arranged with a positive inclination and an array Rc in which the conductive particles are arranged with a negative inclination are provided at a predetermined interval in the y direction, and a zigzag array R that is repeatedly provided is arranged at a predetermined pitch in the x direction while periodically changing the position in the y direction. An anisotropic conductive film is provided.

[0016] The present invention also provides a method for manufacturing a connection structure for anisotropically connecting a terminal of a first electronic component and a terminal of a second electronic component using the above-described anisotropic conductive film.

[0017] The present invention further provides a connection structure in which a first electronic component and a second electronic component are anisotropically conductively connected via the above-described anisotropic conductive film.

[0018] In the present invention, the anisotropic conductive film refers to a film capable of forming an anisotropic conductive connection. The anisotropic conductive connection state refers to a state in which opposing terminals of electronic components having a plurality of terminals are electrically connected, but adjacent terminals are not electrically connected.

Advantages of the Invention

[0019] In the anisotropic conductive film of the present invention, the arrangement of the conductive particles in plan view is a pseudo-random type regular arrangement. Here, the pseudo-random type regular arrangement refers to an arrangement that appears to be a random and uniform arrangement without regularity or reproducibility, but actually has reproducibility and regularity. According to the anisotropic conductive film of the present invention, the arrangement of the conductive particles is a pseudo-random type regular arrangement, and the conductive particles are uniformly distributed to such an extent that unevenness cannot be recognized even by microscopic observation. Therefore, even when the axes of the respective terminals of the terminal row to be connected are parallel in the same direction, whether the terminal row is straight, in a radial fan-out type, with horizontally long terminals, or with deformed wiring bumps, sufficient conductive particles are uniformly captured, and a good conduction state can be obtained.

[0020] In addition, regardless of the orientation in which the anisotropic conductive film is attached to the terminals, a good conduction state can be obtained.

[0021] Furthermore, since the conductive particles are dispersed evenly, it is possible to suppress the occurrence of short circuits even when connecting fine-pitch terminals.

[0022] In addition, since the pseudo-random type regular arrangement has a predetermined periodicity, in the product inspection of the anisotropic conductive film, it is possible to easily inspect whether the conductive particles are arranged in a predetermined pseudo-random type regular arrangement.

Brief Description of the Drawings

[0023]

Figure 1A-1

Figure 1A-2

Figure 1B

Figure 2

Figure 3A

Figure 3B

Figure 4A

Figure 4B

Figure 5A

Figure 5B

Figure 6

Figure 7

Figure 8A

Figure 8B

Figure 9

Figure 10

Figure 11A

Figure 11B

Figure 12A

Figure 12B

Figure 12C

DETAILED DESCRIPTION OF THE INVENTION

[0024] Hereinafter, an anisotropic conductive film according to an embodiment of the present invention will be described in detail with reference to the drawings. In each figure, the same reference numerals represent the same or equivalent components.

[0025] <Overall Structure of Anisotropic Conductive Film> FIG. 1A-1 is a plan view showing the arrangement of conductive particles of the anisotropic conductive film 10A of the embodiment, representing the pseudo-random type regular arrangement 1A possessed by this anisotropic conductive film. FIG. 1A-2 is an enlarged view of FIG. 1A-1. FIG. 2 is a cross-sectional view of the anisotropic conductive film 10A cut in the thickness direction.

[0026] The anisotropic conductive film 10A has a layer structure in which the conductive particles 2 are arranged in a single layer on the surface or in the vicinity of the surface of the insulating resin layer 3, and a low-viscosity resin layer 4 is laminated thereon. In the present invention, the low-viscosity resin layer 4 is provided as needed, and a layer structure in which the low-viscosity resin layer 4 is omitted may be used as shown in the cross-sectional view of the anisotropic conductive film 10B in FIG. 3A. The planar arrangement of the conductive particles 2 of this anisotropic conductive film 10B can be 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, as in the anisotropic conductive film 10C shown in FIG. 3B, the conductive particles 2 may be held in the through holes 3h of the insulating film 3 having the through holes 3h, and the low-viscosity resin layers 4A and 4B may be laminated on the upper and lower surfaces thereof. In this case, the insulating film 3 is a resin layer that is less likely to be deformed by heating and pressing than the low-viscosity resin layers 4A and 4B.

[0027] <Conductive Particles> · Particle Material Examples of the conductive particles 2 include metal particles such as nickel, cobalt, silver, copper, gold, and palladium, alloy particles such as solder, and metal-coated resin particles. Two or more types can also be used in combination. Among them, metal-coated resin particles are preferable because the contact with the terminals is easily maintained due to the repulsion of the resin particles after connection, and the conduction performance is stabilized. Further, the surface of the conductive particles may be subjected to an insulating treatment that does not interfere with the conduction characteristics. For example, insulating fine particles may be attached by a known technique, or an insulating coat may be provided with an insulating resin.

[0028] ·Particle diameter The particle diameter of the conductive particles 2 is appropriately selected according to the application. Usually, in order to suppress an increase in conduction resistance and to suppress the occurrence of a short circuit, it is preferably 1 μm or more and 30 μm or less. For fine pitch applications, it can be preferably 2 μm or more and less than 10 μm, and when an even finer pitch is required, the particle diameter can also be less than 2 μm. The particle diameter of the conductive particles before being dispersed in the insulating resin layer can be measured by a general particle size distribution measuring device, and the average particle diameter can also be determined using a particle size distribution measuring device. As an example of the measuring device, an image type FPIA-3000 (manufactured by Malvern Panalytical) can be mentioned. In this case, it is desirable that the number of samples for measuring the conductive particle diameter is 1000 or more, preferably 2000 or more. The particle diameter of the conductive particles in the anisotropic conductive film can be determined from electron microscope observations such as SEM. In this case, it is desirable that the number of samples for measuring the conductive particle diameter is 200 or more, preferably 1000 or more.

[0029] Regarding the variation in particle diameter, the CV value (coefficient of variation = standard deviation / average) of the particle diameter is preferably 20% or less. Since the variation in particle diameter is small, the margin of the heating and pressing conditions during thermocompression bonding can be increased.

[0030] The aggregation of fine particles can also be regarded as the arrangement of one conductive particle. In that case, it is only necessary that the diameter of this aggregation satisfies a CV value of 20% or less.

[0031] When using, as the conductive particles, those having the above-described insulating treatment on their surfaces, the particle diameter of the conductive particles in the present invention means the particle diameter not including the portion of the insulating treatment.

[0032] <Planar arrangement of conductive particles> FIG. 1A-1 shows a pseudo-random type regular arrangement 1A of the conductive particles 2 included in the anisotropic conductive film 10A, and FIG. 1B is an explanatory diagram of its manufacturing method, showing a state before periodically changing the position in the y direction of the zigzag arrangement R.

[0033] This pseudo-random type regular arrangement 1A can be created as follows. First, in the xy plane, consider a zigzag arrangement R in which the conductive particles 2 are arranged with a positive slope (array Rb) and an arrangement Rc in which the conductive particles 2 are arranged with a negative slope, with a predetermined interval in the y direction, and are repeatedly provided (FIG. 1B). Next, while periodically changing the position of the zigzag arrangement R in the y direction, arrange it at a predetermined pitch in the x direction (FIG. 1A-1). In this case, consider a pattern of conductive particles in which the zigzag arrangement R is arranged at a predetermined pitch in the x direction in advance, and the position of the zigzag arrangement R constituting this pattern of conductive particles may be periodically changed in the y direction.

[0034] More specifically, for example, in order to create the pseudo-random type regular arrangement 1A shown in FIG. 1A-1, first, consider an arrangement Rb in which three conductive particles 2 are arranged at an angle α with respect to the x direction, and an arrangement Rc in which three conductive particles are arranged in a direction in which this arrangement direction is reversed with respect to the x direction. The arrangement direction of the conductive particles in this arrangement Rc is in the direction of angle -α with respect to the x direction (FIG. 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 may be the same or different.

[0035] Next, consider a zigzag arrangement R in which the arrangements Rb and Rc are repeatedly arranged with predetermined intervals L31 and L32 in the y direction (FIG. 1B). In the present invention, the zigzag arrangement R does not necessarily have to be arranged alternately as long as the arrangements Rb and Rc are repeatedly arranged. In this embodiment, the arrangements Rb and Rc are arranged alternately.

[0036] Also, in the zigzag arrangement R, the displacement amounts Ld1 and Ld2 in the x direction between the closest conductive particles of the adjacent arrangements Rb and Rc (FIG. 1B) can be set as appropriate. In this embodiment, since the displacement amount in the x direction between the arrangements Rb repeatedly provided in the y direction and the displacement amount in the x direction between the arrangements Rc are zero, Ld1 = Ld2 = Ld.

[0037] Next, assume that the zigzag array R is arranged in the x direction at a predetermined pitch pa (Fig. 1B). In this case, the position of the zigzag array R in the y direction is made periodic (one period: R1, R2, R3, R4, R5, R6) as shown by the broken line F of the two-dot chain line in Fig. 1A-1 to obtain a pseudo-random type regular arrangement 1A.

[0038] In the present invention, there is no particular limitation on the number of conductive particles constituting the array Rb and the number of conductive particles constituting the array Rc. However, for the convenience of the design of the particle arrangement, the array Rb is preferably formed of 2 to 10, more preferably 2 to 6, still more preferably 2 to 4, and particularly preferably 2 to 3 conductive particles, and the array Rc is also preferably formed of 2 to 10, more preferably 2 to 6, still more preferably 2 to 4, and particularly preferably 2 to 3 conductive particles.

[0039] In this embodiment, since the angle formed by the array Rb with the x direction is α and the angle formed by the array Rc with the x direction is -α, the array directions of the array Rb and the array Rc are symmetric with respect to the x-axis. In the present invention, the absolute values of the angle formed by the array Rb with the x direction and the angle formed by the array Rc with the x direction do not necessarily have to exactly match. However, for the convenience of the design, the ratio of the difference between the absolute values of the angle formed by the array Rb with the x direction and the angle formed by the array Rc with the x direction to the absolute value of the angle formed by the array Rb with the x direction is preferably 20% or less. This makes it easy to create a pseudo-random type regular arrangement with no overlap between the conductive particles and a uniform distribution of the conductive particles. On the other hand, by setting the pitch L1, pitch L2, pitch pa, interval L3, etc., even if the above ratio exceeds 20%, it is possible to create a pseudo-random type regular arrangement with a uniform distribution of the conductive particles. Further, the absolute value of the angle α is preferably 5 to 85°, more preferably 10 to 80°, and still more preferably 15 to 75° in order to ensure the visual irregularity.

[0040] Also, in this embodiment, when the y-direction position of the zigzag array R arranged in the x direction is assumed to be constant, the pitch pa (FIG. 1B) of the zigzag array R in the x direction is constant. However, in the present invention, it is sufficient that this pitch pa has regularity and does not necessarily have to be constant. For example, the pitch pa1 and the pitch pa2 may appear at a predetermined period. However, for the convenience of designing a pseudo-random type regular arrangement, as shown in FIG. 1B, it is preferable that the pitch pa of the zigzag array R in the x direction is constant when the y-direction position of the zigzag array R arranged in the x direction is constant.

[0041] In the present invention, when the swing width in the x direction of the bending line forming the minimum repeating unit Ru (FIG. 1A-2) of the zigzag array R including the adjacent arrays Rb and Rc is defined as Lx, it is preferable that pa > Lx. Thereby, when creating a pseudo-random type regular arrangement, even if the y-direction position of the zigzag array R is periodically changed, it is possible to prevent the conductive particles from overlapping each other. On the other hand, for example, when it is desired to make the conductive particles in the x direction dense, pa ≤ Lx may be set.

[0042] The pitch L1 in the y direction of the conductive particles of the array Rb, the pitch L2 in the y direction of the conductive particles of the array Rc, and the pitch pa in the x direction of the zigzag array R when the y-direction position of the zigzag array R is constant as shown in FIG. 1B may be different from each other. From the viewpoint of making the variation of the conductive particles uniform and facilitating the design of the pseudo-random type regular arrangement, it is preferable that these are substantially equal. Here, the fact that these are substantially equal means that the irregularity and uniformity of the finally obtained pseudo-random type regular arrangement are substantially equal.

[0043] Regarding the interval L3 in the y - direction when the array Rb and the array Rc are alternately arranged in the y - direction, whether the interval L31 when the array Rc is above the array Rb and the interval L32 when the array Rb is above the array Rc are the same or different, a pseudo - random type regular arrangement can be formed. From the point of making the variation of the conductive particles uniform and the point of facilitating the design of the pseudo - random type regular arrangement, it is preferable that there is also regularity in these intervals L31 and L32, and it is more preferable that they are constant and equal. Also, the intervals L31 and L32 may be the same as or different from the above - mentioned pitches L1, L2 and pitch pa. However, it is more preferable that the intervals L31 and L32 are constant and equal, and the interval L3 (L31, L32) is equal to the above - mentioned pitches L1, L2, pa.

[0044] When periodically changing the y - direction position of the zigzag - shaped array R, the pattern of the periodic change is not particularly limited. However, for the bending line forming the minimum repeating unit Ru of the zigzag - shaped array R including adjacent arrays Rb and Rc, a bending line symmetric to this with respect to y = x is formed, and this is set as the bending line F0 corresponding to one period in the x - direction of the zigzag - shaped array R. It is preferable to change the y - direction position of the zigzag - shaped array R along this bending line F0 (Fig. 1A - 2). Thereby, the arrangement of the conductive particles in the repeating unit in the pseudo - random type regular arrangement can be made closer to a particle arrangement symmetric with respect to y = x, and the uniformity of the arrangement of the conductive particles can be improved. Note that the periodic bending line extending in the x - axis direction when periodically changing the y - direction position of the zigzag - shaped array R is not limited to F as described later. When using, as the repeating unit of the periodic bending line extending in the x - axis direction, a bending line symmetric to the bending line forming the minimum repeating unit Ru of the zigzag - shaped array R or a deformed bending line thereof, the axis of symmetry may be y≠x.

[0045] Also, when the change width of the bending line F in the y direction is Ly, it is preferable that Ly < L3 (L31, L32). Thereby, the minimum unit Ru of the repetition of the pseudo-random type regular arrangement is a pattern of conductive particles included in a rectangle U whose length in the x direction is one period length L0x of the zigzag array R and whose length in the y direction is the length L0y in the y direction of the minimum repetition unit Ru of the zigzag array R in the y direction (the pattern in which the conductive particles are filled in dark color in FIGS. 1A-1 and 1A-2). Therefore, when manufacturing an anisotropic conductive film with a pseudo-random type regular arrangement, it becomes easier to inspect whether the conductive particles of the film are arranged in a pseudo-random type regular arrangement. In particular, it is preferable that the number of conductive particles in the minimum repetition unit Ru of the zigzag array R including the adjacent arrays Rb and Rc is equal to the number of arrays in one period in the x direction of the zigzag array R. In this case, when pitch L1 = pitch L2 = interval L3 = pitch pa, the pattern of conductive particles that is the minimum unit of the repetition of the pseudo-random type regular arrangement can be a pattern symmetric with respect to y = x. Thereby, it is preferable because it becomes easier to inspect whether the conductive particles are arranged in a pseudo-random type regular arrangement in the anisotropic conductive film.

[0046] (Modified form of random type regular arrangement) The pseudo-random type regular arrangement 1B shown in FIG. 4A has arrays Rb and Rc each consisting of two conductive particles, with pitch L1 = pitch L2 = interval L3 = pitch pa, deviation amount Ld / pitch pa = 0.25, and angle α = 60°.

[0047] As a method for creating this pseudo-random type regular arrangement 1B, first, consider an arrangement in which the zigzag array R is arranged in the x direction with a pitch pa as shown in FIG. 4B. Next, consider a bending line that forms the minimum repetition unit Ru of the zigzag array R and a bending line F0 symmetric with respect to y = x. Move the zigzag array R arranged with a pitch pa sequentially in the y direction along the bending line F0 and repeat this to obtain the pattern of conductive particles shown in FIG. 4A.

[0048] In this way, by setting pitch L1 = pitch L2 = interval L3 = pitch pa, and making the number of conductive particles forming the minimum repeating unit Ru of the zigzag array R equal to the number of arrays in one period in the x direction of the zigzag array R, a pseudo-random regular arrangement of conductive particles can be formed extremely simply.

[0049] The pseudo-random regular arrangement 1C shown in FIG. 5A has arrays Rb and Rc each consisting of two conductive particles, with pitch L1 = pitch L2 = interval L3 = pitch pa, deviation amount Ld / pitch pa = 0.5, and angle α = 60°.

[0050] Also in the method of creating this pseudo-random regular arrangement 1C, first consider arranging the zigzag array R in the x direction with pitch pa as shown in FIG. 5B, and while changing the position of the zigzag array R in the y direction along the bending line forming the minimum repeating unit Ru of the zigzag array R and the bending line F0 symmetric to y = x, sequentially move it in the y direction and repeat this.

[0051] Note that the pattern of the conductive particles shown in FIG. 5B is a pattern in which the first region where the array Rb is arranged in the x direction with pitch pa and the second region where the array Rc is arranged in the x direction with pitch pa are alternately repeated in the y direction, and the extension line of the axis of the array Rb in the first region also serves as the extension line of the array axis in the second region (that is, the conductive particles in the second region are located on the extension line of the array axis in the first region). However, since the pseudo-random regular arrangement shown in FIG. 5A of this embodiment arranges the zigzag array R in the x direction with pitch pa while changing the position of the zigzag array R in the y direction, in this embodiment, the extension line of the array axis in the first region where the array Rb is arranged in the x direction with pitch pa does not become the extension line of the array axis in the second region where the array Rc is arranged in the x direction with pitch pa.

[0052] In changing the position of the zigzag array R in the y direction in the present invention, the reference bending line F0 is not limited to being symmetric with respect to y = x to the bending line forming the minimum repeating unit Ru of the zigzag array R. For example, the pseudo-random type regular arrangement 1D shown in FIG. 6 is obtained by moving the zigzag array R shown in FIG. 5B arranged in the x direction at a pitch pa along the bending line F0 having the same shape as that in FIG. 4A while moving it in the y direction.

[0053] The pseudo-random type regular arrangement 1E shown in FIG. 7 is obtained by providing a displacement amount Le in the x direction between the arrays Rb1 and Rb2 or between the arrays Rc1 and Rc2 that are repeated in the zigzag array R in the pseudo-random type regular arrangement 1B shown in FIG. 4A. In this arrangement, the displacement amount in the x direction between the closest conductive particles of the adjacent arrays Rb1 and Rc1 is Ld, while the displacement amount in the x direction between the closest conductive particles of the adjacent arrays Rc1 and Rb2 is zero.

[0054] The pseudo-random type regular arrangement 1F shown in FIG. 8A is obtained by further increasing the displacement amount Le in the x direction between the array Rb1 and the array Rb2 with respect to the pseudo-random type regular arrangement 1E shown in FIG. 7. In this way, the direction in which the zigzag array R extends can be obliqued with respect to the y-axis according to the magnitude of the displacement amount Le.

[0055] Note that in the present invention, the xy coordinates are not limited to orthogonal coordinates. For example, FIG. 8B shows the pseudo-random type regular arrangement 1F shown in FIG. 8A above, displayed in non-orthogonal coordinates where the x direction and the y direction are not orthogonal. For design convenience, it is preferable to use orthogonal coordinates.

[0056] <Number density of conductive particles> In the anisotropic conductive film of the present invention, the number density of the conductive particles 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. Usually, since the preferred conditions change depending on the combination and use of the electronic components to be connected, there is no particular limitation on the number density of the conductive particles, but the lower limit is preferably 30 particles / mm 2 or more, and 150 particles / mm2 It may be the above, 1000 pieces / mm 2 or more. If the number density is low, a cost reduction effect can be expected. Also, the upper limit is 500000 pieces / mm in practical use 2 or less, 350000 pieces / mm 2 or less, 70000 pieces / mm 2 or less is preferable, 42000 pieces / mm 2 or less is more preferable. In the case of fine pitch applications, depending on the degree of the fine pitch, for example, 6000 to 35000 pieces / mm 2 is also acceptable, 120000 pieces / mm 2 or more and 350000 pieces / mm 2 or less, particularly 150000 pieces / mm 2 or more and 300000 pieces / mm 2 or less is also acceptable. Also, when 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 .

[0057] As the measurement region when measuring the number density, a plurality of rectangular regions with a side length of 100 μm or more (preferably 5 or more, more preferably 10 or more) are arbitrarily set, and the total area of the measurement regions is 2 mm 2 or more is preferable. The side length and total area of the rectangular region may be adjusted according to the average particle diameter. The size and number of each measurement region may be appropriately adjusted according to the state of the number density. For example, it is sufficient if there are dozens or more conductive particles in one rectangular region. As a more specific example, in the case of an anisotropic conductive film with a relatively large number density of conductive particles for fine pitch applications, 200 locations (2 mm of a region with an area of 100 μm × 100 μm 2 ) are used to measure the number density using observation images obtained by a metal microscope, an electron microscope, etc. (such as SEM or TEM), and the average is obtained by averaging them. The number density may be measured using a three-dimensional surface measurement device, or may be obtained by measuring the observation image using image analysis software (for example, WinROOF manufactured by Mitani Corporation, "A Image-kun" (registered trademark) manufactured by Asahi Kasei Engineering Corporation, etc.).

[0058] Regarding the number density of the conductive particles, it is preferable that the area occupancy rate of the conductive particles calculated by the following formula is 0.3% or more from the viewpoint of reducing the conduction resistance. On the other hand, from the viewpoint of suppressing the thrust required for the pressing jig during connection, this area occupancy rate may be 40% or less, preferably 35% or less, and more preferably 30% or less. Area occupancy rate of conductive particles (%) = [Number density of conductive particles in plan view] × [Average of the planar view areas of two conductive particles] × 100

[0059] <Position of conductive particles in the film thickness direction> It is preferable that the positions of the conductive particles 2 in the film thickness direction are aligned. For example, as shown in FIG. 2, the embedding amounts Lb of the conductive particles 2 in the film thickness direction can be aligned. Thereby, the capture property of the conductive particles 2 at the terminals is likely to be stable. On the other hand, in the present invention, the conductive particles 2 may be exposed from the insulating resin layer 3 or may be completely embedded.

[0060] Here, the embedding amount Lb is the surface of the insulating resin layer 3 in which the conductive particles 2 are embedded (among the front and back surfaces of the insulating resin layer 3, the surface on the side where the conductive particles 2 are exposed, or when the conductive particles 2 are completely embedded in the insulating resin layer 3, the surface close to the conductive particles 2), and is the distance between the tangent plane at the center between adjacent conductive particles and the deepest part of the conductive particles 2.

[0061] 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 or more is arbitrarily extracted from 10 or more locations from the anisotropic conductive film, preferably 50 or more in total, and more preferably 200 or more conductive particles are measured for their embedding amounts, and the average thereof is preferably obtained. 2 It is preferable to measure the embedding amounts of 50 or more, more preferably 200 or more conductive particles, and find their average.

[0062] <Embedding rate> When the ratio of the embedding amount Lb to the average particle diameter D of the conductive particles 2 is defined as the embedding ratio (Lb / D), the embedding ratio is preferably 30% or more and 105% or less. By setting the embedding ratio (Lb / D) to 30% or more, the conductive particles 2 can be maintained at a predetermined position by the insulating resin layer 3, and by setting it to 105% or less, the resin amount of the insulating resin layer that acts to unnecessarily flow the conductive particles between the terminals during anisotropic conductive connection can be reduced.

[0063] <Insulating resin layer> In the anisotropic conductive film of the present invention, the insulating resin layer 3 can be formed using a curable resin composition formed from a polymerizable compound and a polymerization initiator, similar to the insulating resin layer of the anisotropic conductive film described in Japanese Patent No. 6187665. In this case, as the polymerization initiator, a thermal polymerization initiator may be used, a photoinitiator may be used, or they may be used in combination. For example, a cationic polymerization initiator is used as the thermal polymerization initiator, an epoxy resin is used as the thermopolymerizable compound, a photo radical polymerization initiator is used as the photoinitiator, and an acrylate compound is used as the photopolymerizable compound. As the thermal polymerization initiator, a thermal anionic polymerization initiator may be used. As the thermal anionic polymerization initiator, it is preferable to use a microcapsule type latent curing agent formed by using an imidazole-modified body as a core and coating its surface with polyurethane.

[0064] <Minimum melt viscosity of insulating resin layer> The minimum melt viscosity of the insulating resin layer 3 is not particularly limited, but may be 1000 Pa·s or more, and can be the same as the minimum melt viscosity of the insulating resin layer of the anisotropic conductive film described in Japanese Patent No. 6187665. Preferably, it is 1500 Pa·s or more, more preferably 2000 Pa·s or more, still more preferably 3000 to 15000 Pa·s, and particularly preferably 3000 to 10000 Pa·s. This minimum melt viscosity can be determined, for example, using a rotational rheometer (manufactured by TA Instruments), maintaining a constant measurement pressure of 5 g, and using a measurement plate with a diameter of 8 mm. More specifically, it can be determined by setting the temperature range to 30 to 200°C, the heating rate to 10°C / min, the measurement frequency to 10 Hz, and the load fluctuation on the measurement plate to 5 g. The adjustment of the minimum melt viscosity can be performed by changing the type and blending amount of the fine solids contained as a melt viscosity modifier, and the adjustment conditions of the resin composition.

[0065] <Low-viscosity resin layer> The low-viscosity resin layer 4 is a resin layer having a minimum melt viscosity in the range of 30 to 200°C lower than that of the insulating resin layer 3. In the present invention, the low-viscosity resin layer 4 is provided as necessary. By laminating the low-viscosity resin layer 4 on the insulating resin layer 3, when thermocompression bonding the opposing electronic components via the anisotropic conductive film 10A, the space formed by the electrodes or bumps of the electronic components can be filled with the low-viscosity resin layer 4, and the adhesiveness between the electronic components can be improved.

[0066] Moreover, 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 adhesiveness between the electronic components is more likely to be improved. Also, the greater this difference, the relatively smaller the movement amount of the insulating resin layer 3 holding the conductive particles 2 during thermocompression bonding with respect to the low-viscosity resin layer 4, so the capture property of the conductive particles 2 at the terminals is more likely to be improved.

[0067] The minimum melt viscosity ratio of the insulating resin layer 3 to the low-viscosity resin layer 4 depends on the ratio of the layer thicknesses of the insulating resin layer 3 and the low-viscosity resin layer 4, but is preferably 2 or more, more preferably 5 or more, and even more preferably 8 or more. On the other hand, if this ratio is too large, resin extrusion or blocking may occur when a long anisotropic conductive film is formed into a roll, so practically it is preferably 15 or less. More specifically, the preferred minimum melt viscosity of the low-viscosity resin layer 4 satisfies the minimum melt viscosity ratio of the above-described insulating resin layer, and is preferably 3000 Pa·s or less, more preferably 2000 Pa·s or less, and even more preferably 100 to 2000 Pa·s.

[0068] Note that 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 may be formed from a different resin composition.

[0069] <Layer Thickness of Insulating Resin Layer and Low-Viscosity Resin Layer> The layer thickness of the insulating resin layer 3 is preferably 0.3 times or more, more preferably 0.6 times or more, even more preferably 0.8 times or more, and particularly preferably 1 time or more with respect to the average particle diameter D of the conductive particles 2 in order to stably push the conductive particles 2 into the insulating resin layer 3 in the manufacturing process of the anisotropic conductive film described later. Also, the upper limit of the layer thickness of the insulating resin layer 3 can be determined according to the terminal shape, terminal thickness, array pitch, etc. of the electronic component to be connected. However, if the layer thickness becomes too thick, the conductive particles 2 are liable to be unnecessarily affected by resin flow during connection. Therefore, it is preferably 20 times or less, more preferably 15 times or less of the average particle diameter D of the conductive particles 2.

[0070] The low-viscosity resin layer 4 is provided as necessary in the present invention. When the low-viscosity resin layer 4 is provided, the lower limit of its layer thickness is preferably 0.2 times or more, more preferably 1 time or more of the average particle diameter D of the conductive particles 2. Also, regarding the upper limit of the layer thickness of the low-viscosity resin layer 4, if it becomes too thick, the difficulty of laminating with the insulating resin layer 3 increases. Therefore, it is preferably 50 times or less, more preferably 15 times or less, and even more preferably 8 times or less of the average particle diameter D of the conductive particles 2.

[0071] Also, the total thickness of the insulating resin layer 3 and the low-viscosity resin layer 4 is preferably thin from the viewpoints of suppressing unnecessary flow of the conductive particles 2 during connection of electronic components, suppressing resin overflow and blocking when the anisotropic conductive film is formed into a roll, increasing the film length per unit weight of the anisotropic conductive film, etc. However, if it becomes too thin, the handleability of the anisotropic conductive film deteriorates. Also, it becomes difficult to attach the anisotropic conductive film to electronic components, and there is a possibility that the required adhesive force cannot be obtained in the temporary crimping when connecting the electronic components, and there is also a possibility that the required adhesive force cannot be obtained due to insufficient resin amount in the main crimping. Therefore, the total thickness is preferably 0.6 times or more, more preferably 0.8 times or more, still more preferably 1 time or more, and particularly preferably 1.2 times or more with respect to the average particle diameter D of the conductive particles 2.

[0072] The ratio of the thicknesses of the insulating resin layer 3 and the low-viscosity resin layer 4 can be appropriately adjusted according to the combination of electronic components used for connection and the required performance there. These layer 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.

[0073] When at least one of the insulating resin layer and the low-viscosity resin layer is formed into multiple layers (for example, when the anisotropic conductive film has a three-layer structure by sandwiching the insulating resin layer 3 with the low-viscosity resin layers 4A and 4B as shown in FIG. 3B), it is desirable that the relationship of the total thickness of the low-viscosity resin layer and the insulating resin layer satisfies the above-described relationship.

[0074] <Roll of Anisotropic Conductive Film> The anisotropic conductive film of the present invention can be made into a roll form in its product form. There is no particular limitation on the length of the roll form, but from the viewpoint of the handleability of the shipped goods, it is preferably 5000 m or less, more preferably 1000 m or less, and still more preferably 500 m or less. On the other hand, from the viewpoint of mass productivity of the roll form, 5 m or more is preferable. There is no particular limitation on the film width, but from the viewpoint of miniaturization of the mounted body, a narrow width is required. On the other hand, from the viewpoint of the usage method such as anisotropically conducting a plurality of components at once or anisotropically conducting and then cutting them in a certain large size, a large area is required, so there is also a demand for a wide width.

[0075] <Manufacturing method of anisotropic conductive film> There is no particular limitation on the manufacturing method of the anisotropic conductive film of the present invention itself. For example, a transfer mold for arranging conductive particles in a predetermined array is manufactured, the recesses of the transfer mold are filled with conductive particles, and thereon, an insulating resin layer formed on a release film is covered and pressure is applied to press the conductive particles into the insulating resin layer, thereby transferring the conductive particles to the insulating resin layer, or further laminating a low-viscosity resin layer on the conductive particles or on the surface opposite to the surface on which the conductive particles are transferred to manufacture an anisotropic conductive film.

[0076] Also, after filling the recesses of the transfer mold with conductive particles, an insulating resin layer is covered thereon, and the conductive particles are transferred from the transfer mold to the surface of the insulating resin layer without pressing the conductive particles into the insulating resin layer by the transfer mold, and the anisotropic conductive film may be manufactured by pressing the conductive particles on the insulating resin layer into the insulating resin layer after the transfer.

[0077] In addition, as the transfer mold, in addition to those filled with conductive particles in the recesses, those having a micro-adhesive applied to the top surface of the convex portion so that conductive particles adhere to the top surface may also be used. These transfer molds can be manufactured using known techniques such as machining, photolithography, and printing methods.

[0078] In addition, as a method of arranging the conductive particles in a predetermined array, instead of using a transfer type method, a method of filling through-holes provided in a predetermined arrangement with conductive particles (a method of filling through-holes with conductive particles and laminating insulating resin films on both sides thereof), a method of directly spraying conductive particles on a film, a method of stretching a film in which conductive particles are densely arranged, etc. may be used.

[0079] <Method for Connecting Electronic Components Using Anisotropic Conductive Film> As a method of connecting electronic components using the anisotropic conductive film of the present invention, for example, one electronic component is placed on a stage, and the other electronic component is placed thereon via the anisotropic conductive film, and the terminals of both electronic components are anisotropically conductively connected by heating and pressing with a crimping tool to manufacture a connection structure. In this case, the electronic component placed on the stage is a second electronic component such as an IC chip, an IC module, an FPC, a glass substrate, a plastic substrate, a rigid substrate, or a ceramic substrate, and the electronic component heated and pressed with a crimping tool is a first electronic component such as an FPC, a semiconductor element (IC chip, IC module, LED element (mini LED, micro LED, etc.)), a sensor component, or a battery element. As a more detailed method, an anisotropic conductive film is temporarily attached and temporarily crimped to a second electronic component such as various substrates, and a first electronic component such as an IC chip is aligned with the temporarily crimped anisotropic conductive film and thermally crimped to perform anisotropic conductive connection to manufacture a connection structure. Note that the anisotropic conductive film can be temporarily attached to the first electronic component instead of the second electronic component to manufacture a connection structure. Further, the connection method is not limited to thermal crimping, and crimping using photocuring, crimping using both heat and light, etc. may be performed. The types of these electronic components have diversified in recent years and are not limited to these crimping methods. Also, regarding the manufacturing method of the connection structure, since it is prioritized to select an optimal one according to the electronic component, it is not limited to these.

[0080] The anisotropic conductive film of the present invention is highly significant when at least one of the first electronic component and the second electronic component is made of a material that easily thermally expands, such as an FPC or a plastic substrate. When the terminal row is of the fan-out type, it exhibits particular effectiveness. Also, even in the connection of a terminal row where the longitudinal direction of the terminals is not inclined with respect to the arrangement direction of the terminals, or in the connection when the arrangement direction of the terminals is different on each side of the component, such as in the case of peripherally arranged terminals, and further, even if the terminal shape is rectangular or circular, since the conductive particles are uniformly arranged for each terminal, these can be reliably connected and the occurrence of short circuits can be suppressed, and indentation inspection also becomes easy. Therefore, the anisotropic conductive film of the present invention can be generally used regardless of the shape and arrangement of the terminal rows to be connected. The present invention includes a method for manufacturing a connection structure in which the terminals of the first electronic component and the terminals of the second electronic component are anisotropically conductively connected using the anisotropic conductive film of the present invention, and a connection structure in which the first electronic component and the second electronic component are anisotropically conductively connected via the anisotropic conductive film of the present invention.

Example

[0081] Hereinafter, the present invention will be specifically described by way of examples. Example 1 As the arrangement of the conductive particles in the anisotropic conductive film, the pseudo-random type regular arrangement shown in FIG. 4A was simulated. In this case, the diameter of the conductive particles 2 was 3 μm, L1 = L2 = L3 = pa = 8 μm, and the number density of the conductive particles 2 was 16,000 particles / mm 2 was used. The conductive particle pattern in this case is shown in FIG. 9.

[0082] Comparative Example 1 As the arrangement of the conductive particles in the anisotropic conductive film, the regular arrangement shown in FIG. 4B was simulated. In this case, the diameter of the conductive particles 2 was 3 μm, L1 = L2 = L3 = pa = 8 μm, and the number density of the conductive particles 2 was 16,000 particles / mm 2 was used. The conductive particle pattern in this case is shown in FIG. 10.

[0083] Comparative Example 2 The arrangement of conductive particles in the anisotropic conductive film is a hexagonal lattice, the angle γ formed by the lattice axis and the x-direction is 15°, and the number density is 16,000 particles / mm 2 The pattern was simulated.

[0084] Comparative Example 3 The arrangement of conductive particles in the anisotropic conductive film is a hexagonal lattice, the angle γ formed by the lattice axis and the x-direction is 0°, and the number density is 16,000 particles / mm 2 The pattern was simulated.

[0085] (Evaluation) For the anisotropic conductive films of Example 1 and Comparative Examples 1 to 3, when connected to the terminal arrays of Case 1 to 4 in Table 1, (i) the minimum capture number of conductive particles at each individual terminal and (ii) the vertical or horizontal uniformity of the conductive particles captured by the terminal array were examined by simulation.

[0086] Here, (i) the minimum capture number and (ii) the vertical or horizontal uniformity of the conductive particles captured by the terminal array were evaluated according to the following criteria in evaluating pseudo-randomness. (i) Minimum capture number OK: 4 or more NG: 3 or less

[0087] (ii) Uniformity Uniform: When the distribution patterns of the conductive particles captured by the terminals at symmetric vertical or horizontal distances in the terminal array look the same Non-uniform: When the distribution patterns of the conductive particles captured by the terminals at symmetric vertical or horizontal distances in the terminal array do not look the same

[0088] The results are shown in Table 2.

[0089]

Table 1

[0090]

Table 2

[0091] From Table 2, it was confirmed that according to the anisotropic conductive film of the example, capture performance can be obtained even when the orientation with respect to the terminal is different by 90°, and the particles captured with respect to the fan-out terminal are also uniform in the up, down, left, and right directions.

[0092] Also, by comparing FIGS. 9 and 10, it can be seen that the pattern of the example is excellent in visual irregularity.

Explanation of Reference Numerals

[0093] 1A, 1B, 1C, 1D, 1E, 1F, 1B1 Pseudo-random type 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 Bend line F0 Bend line forming the minimum repeating unit Ru of the zigzag arrangement R and the bend line symmetric with respect to y = x 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 Minimum repeating unit of the zigzag arrangement R U Minimum repeating unit of the pseudo-random type regular arrangement α Angle formed by the arrangement Rb in the x direction

Claims

1. An anisotropic conductive film in which conductive particles are disposed in an insulating resin layer, wherein in the xy plane when the anisotropic conductive film is viewed in plan view, an array Rb in which the conductive particles are arranged with a positive inclination and an array Rc in which the conductive particles are arranged with a negative inclination are provided at a predetermined interval in the y direction, and a zigzag array R provided repeatedly is arranged at a predetermined pitch in the x direction while periodically changing the position in the y direction, An anisotropic conductive film in which the pitch pa in the x direction of the zigzag array R is constant when the position in the y direction of the zigzag array R arranged in the x direction is constant.

2. An anisotropic conductive film in which conductive particles are disposed in an insulating resin layer, wherein in the xy plane when the anisotropic conductive film is viewed in plan view, an array Rb in which the conductive particles are arranged with a positive inclination and an array Rc in which the conductive particles are arranged with a negative inclination are provided at a predetermined interval in the y direction, and a zigzag array R provided repeatedly is arranged at a predetermined pitch in the x direction while periodically changing the position in the y direction, An anisotropic conductive film in which the interval L3 in the y direction between the array Rb and the array Rc is constant.

3. An anisotropic conductive film in which conductive particles are disposed in an insulating resin layer, wherein in the xy plane when the anisotropic conductive film is viewed in plan view, an array Rb in which the conductive particles are arranged with a positive inclination and an array Rc in which the conductive particles are arranged with a negative inclination are provided at a predetermined interval in the y direction, and a zigzag array R provided repeatedly is arranged at a predetermined pitch in the x direction while periodically changing the position in the y direction, An anisotropic conductive film in which the number of conductive particles constituting the minimum repeating unit in the zigzag array R is equal to the number of arrays in the x direction of the zigzag array corresponding to one period of the change in the position in the y direction of the zigzag array R.

4. An anisotropic conductive film in which conductive particles are disposed in an insulating resin layer, wherein in the xy plane when the anisotropic conductive film is viewed in plan view, an array Rb in which the conductive particles are arranged with a positive inclination and an array Rc in which the conductive particles are arranged with a negative inclination are provided at a predetermined interval in the y direction, and a zigzag array R provided repeatedly is arranged at a predetermined pitch in the x direction while periodically changing the position in the y direction, An anisotropic conductive film in which the arrangement of the conductive particles in which the conductive particles constituting the minimum repeating unit in the zigzag array R are arranged in the x direction while changing the position in the y direction by one period is symmetric with respect to y = x.

5. The anisotropic conductive film according to any one of Claims 1 to 4, wherein the array Rc is arranged in a direction in which the arrangement direction of the array Rb is reversed with respect to the x direction.

6. The anisotropic conductive film according to claim 1, 3 or 4, wherein the distance L3 in the y direction between the array Rb and the array Rc is constant.

7. The anisotropic conductive film according to any one of claims 1 to 4, wherein the pitch L1 in the y direction of the conductive particles in the array Rb, the pitch L2 in the y direction of the conductive particles in the array Rc, and the distance L3 are equal.

8. The anisotropic conductive film according to any one of claims 1 to 4, wherein the pitch pa in the x direction of the zigzag array R arranged in the x direction, the pitch L1 in the y direction of the conductive particles in the array Rb, the pitch L2 in the y direction of the conductive particles in the array Rc, and the distance L3 are equal.

9. The anisotropic conductive film according to any one of claims 1 to 4, wherein the change width Ly in the y direction of the zigzag array R is less than the distance L3.

10. The anisotropic conductive film according to claim 1, 2 or 4, wherein the number of conductive particles constituting the repeating minimum unit in the zigzag array R is equal to the number of arrays in the x direction of the zigzag array corresponding to one period of the change in the y direction position of the zigzag array R.

11. The anisotropic conductive film according to any one of claims 1 to 3, wherein the arrangement of the conductive particles arranged in the x direction while changing the position in the y direction by one period in the zigzag array R is symmetric with respect to y = x.

12. The anisotropic conductive film according to any one of claims 1 to 11, wherein the swing width Lx in the x direction of the zigzag array R is smaller than the pitch pa in the x direction of the zigzag array R arranged in the x direction.

13. A method for manufacturing a connection structure for anisotropically conducting a terminal of a first electronic component and a terminal of a second electronic component using the anisotropic conductive film according to any one of claims 1 to 12.

14. A connection structure in which a first electronic component and a second electronic component are anisotropically conductively connected via the anisotropic conductive film according to any one of claims 1 to 12.

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