A method of dispersing conductive particles in an ACF adhesive film

Abstract

The present application relates to the technical field of conductive adhesive film preparation, and discloses a method for arranging and dispersing conductive particles in an ACF adhesive film. The method comprises the following steps: (1) preparing a vacuum adsorption roller with a low-adhesion material on the outer surface, and the cylindrical side wall of the roller is provided with arrayed holes; (2) starting a vacuum pump to keep the vacuum degree in the roller at 10 4 ~10 6 Pa, so that the conductive particles are adsorbed on the holes; when the roller rolls, an adhesive film with a viscosity greater than or equal to the vacuum adsorption force moves synchronously with the roller to adhere the conductive particles to the adhesive film, thereby forming an adhesive film layer containing arrayed conductive particles; and (3) pasting a non-conductive layer (NCF) on the adhesive film layer to form a double-layer structure anisotropic conductive adhesive film. The present application combines the roller and vacuum adsorption to solve the problems of conductive particle aggregation, uneven arrangement and cavities, and has low cost and high efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of conductive adhesive film preparation, in particular to a method for arranging and dispersing conductive particles in an ACF adhesive film. BACKGROUND

[0002] With the miniaturization, high precision and high performance of electronic devices, traditional tin soldering technology cannot meet the requirements of microelectronic packaging. Anisotropic conductive adhesive film (ACF) emerges as a new type of electronic packaging adhesive material. Compared with traditional tin soldering materials, ACF has the advantages of environmental friendliness, small bonding pitch, simple operation process and low processing temperature.

[0003] Currently, conductive particles in anisotropic conductive adhesive film (ACF) are mostly randomly dispersed in the polymer resin. The existing conductive particle dispersion process puts the conductive particles into the glue for stirring and mixing, which has the problem of uneven dispersion or agglomeration of conductive particles. With the miniaturization development of many electronic products, random dispersion of conductive particles cannot meet the needs of high-precision and fine-pitch packaging.

[0004] Arranging and dispersing conductive particles in an array in the glue can solve the problem of uneven dispersion of conductive particles and can be applied to fine packaging processes. As an array configuration method of conductive particles, there are many methods applied, such as magnetic field control method, electric field control method, template method, photolithography method, laser method, etc., but these processes have the problems of high cost and low efficiency.

[0005] Chinese patent CN 118098705 A discloses a preparation method of an anisotropic conductive film with an array of conductive particles: processing an array opening cavity on the surface of the upper roller, filling one conductive particle in each opening cavity by magnetic attraction of the upper roller, and then transferring the conductive particles to the base film material between the two rollers by magnetic attraction of the lower roller to realize uniform arrangement of the conductive particles, but there are still the following defects:

[0006] (1) It will give the so-called residual magnetism to the conductive particles, and when the conductive particles have magnetism, they may be attracted to each other to cause particle aggregation;

[0007] (2) The magnetic field is relatively difficult to control, and there is a possibility that the particles on the surface of the roller (non-hole area) will be attracted to the surface of the roller due to strong magnetic strength, resulting in transfer together during transfer;

[0008] (3) Magnetic attraction may also cause particles to be attracted to other particles to form a particle stack in the hole of the roller.

[0009] The existing template method is to use a template with micro-holes or patterns (such as PDMS, metal template) to guide the positioning of particles, then the template is covered on the surface of the adhesive film, and the particles are filled into the micro-holes by vacuum adsorption or pressure, and then the excess particles are scraped off. After removing the template, the particles remain in the predetermined position. The template adsorption method has the following disadvantages:

[0010] (1) If the conductive particles with a particle size smaller than the specification value of the hole diameter are adsorbed in the hole, the particles with a size smaller than the specification cannot be transferred to the adhesive film to form a cavity;

[0011] (2) When the conductive particles are dispersed on the template and the remaining conductive particles are scraped off, there is a probability that no particles are formed in the hole of the template due to uneven dispersion;

[0012] (3) If the adhesion between the conductive particles and the adhesive film is poor, the particles may be displaced during the removal of the template;

[0013] (4) The template has high manufacturing cost, is easy to wear, and has slow process speed, which affects the production efficiency;

[0014] (5) The uneven surface of the template affects the contact between the particles and the template, resulting in uneven adsorption.

[0015] Chinese patent CN 117143542 A discloses a preparation method of anisotropic conductive adhesive film with regular arrangement of conductive particles. The regular arrangement of conductive particles on the adhesive film is realized by a conductive particle adsorption device. The conductive particle adsorption device includes a closed cavity with an air vent at the top and micro-holes arranged in an array at the bottom. The air vent is connected to a vacuum pipe and a compressed air pipe through a three-way connector. During the arrangement of conductive particles, vacuum is applied in the closed cavity to adsorb the conductive particles on the micro-holes, and then compressed air is introduced into the closed cavity to eject the conductive particles from the micro-holes to the adhesive film. Because the adhesive film is moving during production, the movement speed of the device cannot be completely synchronized with the adhesive film during the ejection of particles. Moreover, it is difficult to precisely move the device to the next locking position. In addition, the air flow may contact the adhesive film during the ejection of particles, and the adhesive film may be blown out of the cavity. Therefore, in the actual application process, there are problems such as cavities, irregular arrangement of conductive particles, and even aggregation of conductive particles, as shown in the accompanying drawings of Chinese patent CN 117143542 A. Figure 7

[0016] Therefore, there is an urgent need to develop a method for arranging and dispersing conductive particles in ACF adhesive film to solve the problems of aggregation of conductive particles, irregular arrangement of conductive particles, cavities, and the like, reduce the cost, and improve the production efficiency. SUMMARY

[0017] ​In view of the above problems, the present application aims to provide a method for arranging and dispersing conductive particles in ACF adhesive film. The present application combines a roller and vacuum adsorption, reduces cost, improves production efficiency, and solves the problems of conductive particle aggregation, irregular arrangement, and cavities.

[0018] To achieve the above-mentioned purposes, the present application adopts the following technical solutions:

[0019] A method for arranging and dispersing conductive particles in ACF adhesive film, comprising the following steps:

[0020] (1) preparing a vacuum adsorption roller;

[0021] The vacuum adsorption roller comprises a roller, a plurality of holes arranged in an array through the cylindrical side wall of the roller, and a vacuum pump connected to the inside of the roller; at least the outer material of the roller is a low-adhesion material;

[0022] (2) conductive particle adsorption and transfer;

[0023] The vacuum pump is turned on, and the vacuum degree in the roller is maintained at 10 4 ~ 10 6 Pa, so that the conductive particles are adsorbed on the holes; when the roller rolls, an adhesive film with a viscosity greater than or equal to the vacuum adsorption force moves synchronously with the roller, and the conductive particles are adhered to the adhesive film to form an adhesive film layer containing arrayed conductive particles;

[0024] (3) adhesive film compounding:

[0025] A non-conductive layer NCF is attached to the adhesive film layer containing arrayed conductive particles to form a double-layer structure anisotropic conductive adhesive film.

[0026] Conductive particle vacuum adsorption calculation formula:

[0027]

[0028]

[0029]

[0030] In some embodiments, at least the outer material of the roller is polytetrafluoroethylene. Preferably, it is polytetrafluoroethylene of Kumo PTFE 857-203 or Whitford Xylan® 1000 series.

[0031] Preferably, the distance between the upper end surface of the roller and the lower end surface of the adhesive film is within 3 μm.

[0032] Preferably, the adhesive film in step (2) comprises the following components by mass percentage: liquid epoxy resin 5-30%, solid phenoxy resin 15-55%, toughening agent 5-20%, latent curing agent 10-45%; the liquid epoxy resin is selected from one or a combination of Guodou YD127, YD-128S, Hengman ARALDITE® MY 790-1, ARALDITE® GY 285; the solid phenoxy resin is selected from one or a combination of Hengman PKHH, PKHB, PKHC; the toughening agent material is selected from one or a combination of DOW Paraloid_BTA-751, TMS-2670; the latent curing agent is Asahi Kasei HX-3941 or HX-3088;

[0033] The adhesive film is prepared by the following method: first, dissolving the solid phenoxy resin in a solvent to obtain a dissolved material with a solid content of 40-70%; then mixing the liquid epoxy resin with the dissolved material, the toughening agent and the latent curing agent to obtain a liquid adhesive with a solid content of 50-80%; coating the liquid adhesive on the surface of the release film 1 to form an adhesive film with a thickness of 5-15 μm;

[0034] The solvent is one or a combination of butanone, toluene, ethyl acetate, propylene glycol methyl ether acetate.

[0035] In some embodiments, the holes are conical holes with a taper of 15-30 degrees or straight-through holes, and the hole diameter of the holes is 1 / 2-1 / 3 of the particle diameter of the conductive particles.

[0036] In some embodiments, the distance between adjacent holes is 1 / 2-3 / 2 times the diameter of the conductive particles.

[0037] In some embodiments, the holes can adsorb conductive particles with a particle size of 1-20 μm, and the specific gravity of the conductive particles is 1-9.

[0038] In some embodiments, the conical holes form one or more pattern arrangements. The patterns are determined according to different chip pins of the application end. These patterns include triangular, circular, square, rectangular, hexagonal, octagonal, conical, elliptical, etc.

[0039] Preferably, the non-conductive layer NCF comprises the following components by mass percentage: liquid epoxy resin 5-30%, solid phenoxy resin 15-55%, toughening agent 5-20%, latent curing agent 10-45%; the liquid epoxy resin is selected from one or a combination of Guodou YD127, YD-128S, Hengman ARALDITE® MY 790-1, ARALDITE® GY 285; the solid phenoxy resin is selected from one or a combination of Hengman PKHH, PKHB, PKHC; the toughening agent material is selected from one or a combination of DOW Paraloid_BTA-751, TMS-2670; and the latent curing agent is Asahi Kasei HX-3941 or HX-3088.

[0040] The non-conductive layer NCF is prepared by the following method: first, dissolving the solid phenoxy resin in a solvent to obtain a dissolved material with a solid content of 40-70%; then mixing the liquid epoxy resin with the dissolved material, the toughening agent and the latent curing agent to obtain a liquid glue with a solid content of 50-80%; and coating the liquid glue on the surface of the release film 2 to form a non-conductive layer NCF with a thickness of 10-20 μm.

[0041] The solvent is one or a combination of butanone, toluene, ethyl acetate, propylene glycol methyl ether acetate.

[0042] Compared with the prior art, the present application has the following beneficial effects:

[0043] The present application combines the roller and vacuum adsorption together, reduces the cost, improves the production efficiency, and also solves the problems of aggregation, irregular arrangement and cavities of the conductive particles.

[0044] When the particle size of the conductive particles is smaller than the specification value, the small particle size conductive particles can be sucked into the roller and then adsorbed on the roller again to cover the normal specification value conductive particles on the roller and be transferred to the adhesive film, without causing cavities or small specification value conductive particles on the adhesive film.

[0045] Compared with the prior art of first adsorbing the particles and then moving them to the adhesive film for shooting and covering, the present application uses the roller adsorption and transfer, and the roller speed is the same as the adhesive film moving speed, so there is no problem of irregular arrangement and cavities. BRIEF DESCRIPTION OF DRAWINGS

[0046] Figure 1 is a schematic diagram of the present application for arranging and dispersing the conductive particles on the ACF adhesive film;

[0047] Figure 2 is a structural schematic diagram of the conical hole in the present application;

[0048] Figure 3 is a structural schematic diagram of the vacuum adsorption roller in the present application;

[0049] Figure 4 is the structural diagram of the roller in the present application;

[0050] Figure 5 is the pattern arrangement (triangle) diagram on the roller in the present application;

[0051] Figure 6 is the pattern arrangement (circle) diagram on the roller in the present application;

[0052] Figure 7 is the pattern arrangement (square and rectangle) diagram on the roller in the present application;

[0053] Figure 8 is the pattern arrangement (hexagon) diagram on the roller in the present application;

[0054] Figure 9 is the adhesive film adsorption force diagram under the condition of different distances between the adhesive film and the roller;

[0055] Figure 10 is the electron microscope diagram of the ACF adhesive film after the roller transfer printing with the surface of stainless steel material;

[0056] Figure 11 is the electron microscope diagram of the ACF adhesive film after the roller transfer printing with the surface of polytetrafluoroethylene;

[0057] Figure 12 is the electron microscope diagram of the ACF adhesive film prepared by Comparative Example 1;

[0058] Figure 13 is the electron microscope diagram of the ACF adhesive film prepared by Comparative Example 2;

[0059] Figure 14 is the electron microscope diagram of the ACF adhesive film prepared by Example 1. DETAILED DESCRIPTION

[0060] The present application will be further described in conjunction with examples. It should be noted that the examples do not limit the scope of the present application.

[0061] Unless otherwise defined, the technical or scientific terms used in the present application shall have the ordinary meaning understood by a person with ordinary skill in the art to which the present application pertains.

[0062] The present application will be further described in conjunction with examples. It should be noted that the examples do not limit the scope of the present application.

[0063] As Figures 1-4 shown, the embodiment of the present application provides a method for arranging and dispersing conductive particles in ACF adhesive film, comprising the following steps:

[0064] (1) preparing a vacuum adsorption roller;

[0065] The vacuum adsorption roller comprises a roller 1, a plurality of holes 2 arranged in an array through the cylindrical side wall of the roller, and a vacuum pump connected to the inside of the roller; at least the outer material of the roller is a low-adhesion material;

[0066] In the embodiment of the present application, the roller can be made of polytetrafluoroethylene material, or other materials coated with polytetrafluoroethylene, preferably polytetrafluoroethylene of KOMO PTFE 857-203 or Whitford Xylan® 1000 series. As Figure 1 、 3 shown, the holes 2 pass through the inside and outside of the cylindrical side wall of the roller, regardless of whether the roller side wall has one layer or several layers of material, they all need to pass through the inside and outside of the roller side wall. The vacuum pump can be connected to the inside of the roller from the center of the bottom surface of the roller cylinder, as Figure 3 shown.

[0067] In the embodiment of the present application, the holes on the roller are set by femtosecond laser. The pulse duration is extremely short (1 femtosecond = 10 - ¹ 5 seconds), the energy is deposited and the material is removed before the heat conduction of the roller material, almost no heat melting, recasting layer and micro-cracks, achieving "cold processing". This makes the processing edge very sharp, can accurately control the removed area, so as to punch out the micro-holes with clear profile without changing the hole size over time.

[0068] (2) adsorption and transfer of conductive particles;

[0069] Turn on the vacuum pump and keep the vacuum degree in the roller at 10 4 ~ 10 6 Pa, so that the conductive particles 3 are adsorbed on the holes 2; when the roller rolls, the adhesive film 4 with viscosity greater than or equal to the vacuum adsorption force moves synchronously with the roller, adheres the conductive particles to the adhesive film, and forms an adhesive film layer containing arrayed conductive particles;

[0070] (3) adhesive film compounding:

[0071] The non-conductive layer NCF is attached to the adhesive film layer containing arrayed conductive particles to form a double-layer structure anisotropic conductive adhesive film.

[0072] Conductive particle vacuum adsorption calculation formula:

[0073]

[0074]

[0075] Preferably, the distance between the upper end surface of the roller and the lower end surface of the adhesive film is within 3 μm.

[0076] In some embodiments, the adhesive film in step (2) comprises the following components by mass percentage: liquid epoxy resin 5-30%, solid phenoxy resin 15-55%, toughening agent 5-20%, latent curing agent 10-45%; the liquid epoxy resin is selected from one or a combination of YD 127, YD-128S, HENS MANN ARALDITE® MY 790-1, ARALDITE® GY285; the solid phenoxy resin is selected from one or a combination of HENS MANN PKHH, PKHB, PKHC; the toughening agent material is selected from one or a combination of DOW Paraloid_BTA-751, TMS-2670; the latent curing agent is KUREHA HX-3941 or HX-3088.

[0077] The adhesive film is prepared by the following method: first, dissolving the solid phenoxy resin in a solvent to obtain a dissolved material with a solid content of 40-70%; then mixing the liquid epoxy resin with the dissolved material, the toughening agent and the latent curing agent to obtain a liquid adhesive with a solid content of 50-80%; coating the liquid adhesive on the surface of the release film 1 to form an adhesive film with a thickness of 5-15 μm.

[0078] The solvent is one or a combination of butanone, toluene, ethyl acetate, propylene glycol methyl ether acetate.

[0079] In some embodiments, the holes are conical holes with a taper of 15-30 degrees or straight-through holes, as shown in Figures 2-3 The hole diameter of the holes is 1 / 2-1 / 3 of the particle diameter of the conductive particles.

[0080] In some embodiments, the distance between adjacent holes is 1 / 2-3 / 2 of the diameter of the conductive particles.

[0081] In some embodiments, the conical holes can adsorb conductive particles with a particle diameter of 1-20 μm, and the specific gravity of the conductive particles is 1-9.

[0082] In some embodiments, the conical holes form one or more pattern arrangements. These patterns include triangles, circles, squares, rectangles, hexagons, octagons, cones, ellipses, etc., as shown in Figures 5-8

[0083] ​The non-conductive layer NCF can adopt all non-conductive layers NCF of prior art. In the embodiment of the present application, the non-conductive layer NCF comprises the following components by mass percentage: liquid epoxy resin 5-30%, solid phenoxy resin 15-55%, toughening agent 5-20%, latent curing agent 10-45%; the liquid epoxy resin is selected from one or combination of Guodou YD127, YD-128S, Hengman ARALDITE® MY 790-1, ARALDITE® GY 285; the solid phenoxy resin is selected from one or combination of Hengman PKHH, PKHB, PKHC; the toughening agent material is selected from one or combination of DOW Paraloid_BTA-751, TMS-2670; the latent curing agent is Asahi Kasei HX-3941 or HX-3088;

[0084] The non-conductive layer NCF is prepared by the following method: first, the solid phenoxy resin is dissolved in a solvent to obtain a dissolved material with solid content of 40-70%; then, the liquid epoxy resin is mixed with the dissolved material, the toughening agent and the latent curing agent to obtain a liquid glue with solid content of 50-80%; the liquid glue is coated on the surface of the release film 2 to form a non-conductive layer NCF with thickness of 10-20 μm;

[0085] The solvent is one or combination of butanone, toluene, ethyl acetate, propylene glycol methyl ether acetate.

[0086] I. Optimal distance between the film and the roller

[0087] Figure 9 is a schematic diagram of the film adsorption force under different distances between the film and the roller. It can be seen that: Figure 9 the greater the distance, the smaller the adsorption force, so the optimal distance between the film and the roller is 1 / 2-1 / 4 of the diameter of the conductive particles.

[0088] II. Surface material of the roller

[0089] Table 1 Performance data of different roller materials

[0090]

[0091] According to the advantages and disadvantages of the roller materials in Table 1, stainless steel and polytetrafluoroethylene are selected as the roller materials and applied to the embodiment of the present application.

[0092] The roller with stainless steel surface is selected, and the conductive particles adhere to the surface of the roller, resulting in agglomerated particles being transferred to the film, as shown in Figure 10 .

[0093] The roller with polytetrafluoroethylene surface is selected, and there are no particles adhering to the surface of the roller, and no agglomeration phenomenon is observed after being transferred to the film, as shown inFigure 11 As shown in FIG. 1.

[0094] III. Study on the vacuum adsorption force of the roller and the adhesive film viscosity

[0095] Table 2 is a performance ratio table of the vacuum adsorption force of the roller and the adhesive film viscosity

[0096]

[0097] From Table 2, it can be concluded that the adsorption capacity and the adhesive film viscosity force ratio are required to achieve the required transfer capacity of the particles.

[0098] IV. Study on the roller speed and the adhesive film moving speed

[0099] When the roller speed and the adhesive film moving speed do not match, it is easy to cause displacement of the particle arrangement. In order to verify the influence of the roller speed on the arrangement effect of the conductive particles in the method of the present application and determine the best process window, the following Example 1 and Comparative Examples 1-2 are compared and analyzed:

[0100] Example 1 (medium speed)

[0101] Implementation condition: The roller speed is optimized to 15 rpm.

[0102] Effect: At this speed, the rotation of the roller and the vacuum adsorption and particle transfer process reach a dynamic balance. On the one hand, the vacuum system has sufficient time to ensure that each conical hole can adsorb a conductive particle; on the other hand, the contact time of the adhesive film and the particles is just right, which can achieve nearly 100% complete and orderly transfer. The ACF adhesive film obtained finally has a high degree of regular single-layer and array distribution of the conductive particles inside, the particle spacing is uniform, and there is no aggregation or missing phenomenon, as shown in FIG. 2. Figure 14

[0103] Comparative Example 1 (low speed)

[0104] Implementation condition: The roller speed is controlled at 1 rpm.

[0105] Effect: Because the speed is too slow, the time for the roller to pass through the adhesive film per unit area is too long. This causes the conductive particles on a single conical hole to be in contact and pulled by the adhesive film viscosity layer for a long time, and part of the particles are displaced or turned when they are separated from the hole, which destroys the preset array order. In the adhesive film layer finally formed, the conductive particles are unevenly distributed, there are local aggregation and missing phenomena, and the particle array regularity is poor, as shown in FIG. 3. Figure 12

[0106] Comparative Example 2 (high speed)

[0107] Implementation condition: The roller speed is increased to 80 rpm.

[0108] ​​Effect: Due to the excessively high rotating speed, the vacuum adsorption system cannot fill enough conductive particles into each passing conical hole, which is called "insufficient adsorption". Meanwhile, the contact time between the adhesive film and the roller is too short, which results in that part of the adsorbed particles cannot be effectively and completely transferred to the adhesive film, and the transfer rate is significantly reduced. In the finally formed adhesive film layer, the density of conductive particles is low, and there are a large number of unfilled blank areas, which cannot guarantee the reliable connection of the circuit, such as Figure 13

[0109] To quantify the above effect, we tested the performance of the ACF adhesive film samples prepared at different rotating speeds, and the results are shown in Table 3 below:

[0110] Table 3 Performance test results of ACF adhesive film prepared by Example 1 and Comparative Examples 1-2 at different rotating speeds

[0111]

[0112] In the preferred medium rotating speed range (5-35 rpm) of the present application, a conductive particle array with high density and high uniformity can be obtained at the same time, thereby realizing excellent conductive anisotropy.

[0113] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application and not to limit them. Although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can still be modified or replaced by equivalents, and these modifications or replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present application.​

Claims

1. A method for arranging and dispersing conductive particles in an ACF film, characterized in that, Includes the following steps: (1) Preparation of vacuum adsorption roller; The vacuum adsorption roller includes a roller, a plurality of holes penetrating the cylindrical sidewall of the roller and arranged in an array, and a vacuum pump connected to the inside of the roller; at least the outer surface material of the roller is a low-adhesion material. (2) Adsorption and transfer of conductive particles; Turn on the vacuum pump and maintain a vacuum level of 10 inside the drum. 4 ~10 6 Pa causes conductive particles to adhere to the pores; as the roller rolls, a film with a viscosity greater than or equal to the vacuum adsorption force moves synchronously with the roller, adhering the conductive particles to the film to form a film layer containing an array of conductive particles. (3) Film lamination: A non-conductive NCF layer is laminated onto an adhesive film layer containing arrayed conductive particles to form a bilayer anisotropic conductive adhesive film. The distance between the upper end face of the roller and the lower end face of the adhesive film is within 3μm; the hole is a conical hole with a taper of 15-30 degrees or a straight hole, and the diameter of the hole is 1 / 2 to 1 / 3 of the particle size of the conductive particles.

2. The method for arranging and dispersing conductive particles in an ACF film according to claim 1, characterized in that, The outermost material of the roller is polytetrafluoroethylene.

3. The method for arranging and dispersing conductive particles in an ACF film according to claim 1, characterized in that, The adhesive film in step (2) comprises the following components by weight percentage: 5-30% liquid epoxy resin, 15-55% solid phenoxy resin, 5-20% toughening agent, and 10-45% latent curing agent; the liquid epoxy resin is selected from one or a combination of Guodu YD127, YD-128S, Huntsman ARALDITE® MY 790-1, and ARALDITE® GY 285; the solid phenoxy resin is selected from one or a combination of Huntsman PKHH, PKHB, and PKHC; the toughening agent is selected from one or a combination of DOWParaloid_BTA-751 and TMS-2670; and the latent curing agent is Asahi Kasei HX-3941 or HX-3088. The adhesive film is prepared by the following method: first, solid phenoxy resin is dissolved in a solvent to obtain a solvent material with a solid content of 40-70%; then, liquid epoxy resin is mixed with the solvent material, toughening agent and latent curing agent to obtain a liquid adhesive with a solid content of 50-80%; the liquid adhesive is coated on the surface of release film 1 to form an adhesive film with a thickness of 5-15 μm. The solvent is one or a combination of butanone, toluene, ethyl acetate, and propylene glycol methyl ether acetate.

4. The method for arranging and dispersing conductive particles in an ACF film according to claim 1, characterized in that, The distance between adjacent holes is 1 / 2 to 3 / 2 times the diameter of the conductive particle.

5. The method for arranging and dispersing conductive particles in an ACF film according to claim 1, characterized in that, The pores can adsorb conductive particles with a diameter of 1 to 20 μm, and the specific gravity of the conductive particles is 1 to 9.

6. The method for arranging and dispersing conductive particles in an ACF film according to claim 1, characterized in that, The conical holes form one or more patterns.

7. The method for arranging and dispersing conductive particles in an ACF film according to claim 6, characterized in that, The patterns include triangles, circles, squares, rectangles, hexagons, octagons, cones, and ellipses.

8. The method for arranging and dispersing conductive particles in an ACF film according to claim 1, characterized in that, The non-conductive NCF layer comprises the following components by weight percentage: 5-30% liquid epoxy resin, 15-55% solid phenoxy resin, 5-20% toughening agent, and 10-45% latent curing agent; the liquid epoxy resin is selected from one or a combination of Guodu YD127, YD-128S, Huntsman ARALDITE® MY 790-1, and ARALDITE® GY 285; the solid phenoxy resin is selected from one or a combination of Huntsman PKHH, PKHB, and PKHC; the toughening agent is selected from one or a combination of DOWParaloid_BTA-751 and TMS-2670; and the latent curing agent is Asahi Kasei HX-3941 or HX-3088. The non-conductive NCF layer is prepared by the following method: first, solid phenoxy resin is dissolved in a solvent to obtain a solvent material with a solid content of 40-70%; then, liquid epoxy resin is mixed with the solvent material, toughening agent and latent curing agent to obtain a liquid adhesive with a solid content of 50-80%; the liquid adhesive is coated on the surface of release film 2 to form a non-conductive NCF layer with a thickness of 10-20 μm. The solvent is one or a combination of butanone, toluene, ethyl acetate, and propylene glycol methyl ether acetate.

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