Method for arranging and dispersing conductive particles in ACF adhesive film

Abstract

The invention 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 of which the appearance is made of a low-adhesion material, wherein array type holes are formed in the cylindrical side wall of the roller; (2) a vacuum pump is started, the vacuum degree in the roller is kept to be 104-106 Pa, and the conductive particles are adsorbed to the holes; when the roller rolls, a layer of adhesive film with the viscosity greater than or equal to the vacuum adsorption force moves synchronously with the roller, the conductive particles are adhered to the adhesive film, and an adhesive film layer containing the array type conductive particles is formed; and (3) pasting a non-conductive layer (NCF) on the adhesive film layer to form the anisotropic conductive adhesive film with the double-layer structure. The roller and vacuum adsorption are combined, the problems of conductive particle aggregation, uneven arrangement and holes are solved, the cost is low, and the efficiency is high.

Description

Technical Field

[0001] This invention relates to the field of conductive adhesive film preparation technology, specifically a method for arranging and dispersing conductive particles in an ACF adhesive film. Background Technology

[0002] As electronic devices become increasingly miniaturized, precise, and high-performance, traditional soldering techniques can no longer meet the requirements of microelectronic packaging. Anisotropic conductive film (ACF) has emerged as a novel electronic packaging adhesive material. Compared to traditional soldering materials, ACF offers advantages such as environmental friendliness, small bonding spacing, simple processing, and low processing temperature.

[0003] Currently, conductive particles in anisotropic conductive films (ACF) are mostly randomly dispersed in the polymer resin. Existing conductive particle dispersion processes involve adding conductive particles into the resin and stirring to mix them, which results in uneven dispersion or agglomeration of the conductive particles. With the miniaturization of many electronic products, random dispersion of conductive particles cannot meet the requirements of high-precision, fine-pitch packaging.

[0004] Dispersing conductive particles in an array within the adhesive can solve the problem of uneven dispersion of conductive particles and is applicable to micro-encapsulation processes. Various methods have been used for arraying conductive particles, such as magnetic field control, electric field control, template methods, photolithography, and laser methods; however, these processes suffer from high costs and low efficiency.

[0005] Chinese patent CN 118098705 A discloses a method for preparing an anisotropic conductive film with an array of conductive particles: an array of open cavity bodies are processed on the surface of an upper roller; each open cavity body is filled with a conductive particle by magnetic attraction from the upper roller; and the conductive particles are then transferred to the base film material between the two rollers by magnetic attraction from the lower roller, achieving a uniform arrangement of conductive particles. However, the following defects still exist: (1) It will give conductive particles so-called remanence. When conductive particles are magnetic, they may attract each other and cause particle aggregation. (2) The magnetic field is relatively difficult to control. There is a chance that the magnetic strength of the magnetic field may also be attracted to the surface of the roller (non-hole area) and transferred together during the transfer process. (3) Magnetic adsorption may also occur in the drum holes. Due to their magnetic properties, the particles may adsorb other particles to form a particle stack.

[0006] Existing template-based methods use templates with micropores or patterns (such as PDMS or metal templates) to guide particle positioning. The template is then placed on the film surface, and particles are filled into the micropores through vacuum adsorption or pressure. Excess particles are then scraped off. After removing the template, the particles remain in their predetermined positions. However, template-based adsorption methods have the following drawbacks: (1) If the particle size of conductive particles is smaller than the specified value of the hole diameter, they will also be adsorbed in the hole, causing small particles outside the specification to be unable to transfer to the film and form a cavity. (2) When the conductive particles are dispersed on the template and the remaining conductive particles are scraped off, there is a chance that there will be no particles in the template holes due to uneven dispersion. (3) If the conductive particles do not adhere well to the adhesive film, there is a chance that the particles will be touched and displaced during the removal of the template. (4) The template is expensive to make, easily worn, and the process is slow, which affects production efficiency; (5) Uneven template surface will affect the contact between particles and template, resulting in uneven adsorption. Chinese Patent CN 117143542 A discloses a method for preparing an anisotropic conductive film with regularly arranged conductive particles. The method utilizes a conductive particle adsorption device to achieve the regular arrangement of conductive particles on the film. This device includes a sealed cavity with an air vent at the top and an array of micropores at the bottom. The air vent is connected to a vacuum line and a compressed air line via a three-way connector. During particle arrangement, a vacuum is created within the sealed cavity to adsorb the conductive particles onto the micropores. Compressed air is then introduced into the sealed cavity to eject the conductive particles from the micropores onto the film. However, because the film is dynamically moving during production, the device's movement speed cannot be perfectly synchronized with the film's movement when ejecting particles. Furthermore, it is difficult to precisely lock onto the next position with each movement. Additionally, airflow can blow out voids into the film during particle ejection. Therefore, in practical applications, voids, uneven arrangement of conductive particles, and even particle aggregation exist, as described in Appendix to Chinese Patent CN 117143542 A. Figure 7 As shown.

[0007] Therefore, there is an urgent need to develop a method to arrange and disperse conductive particles in an ACF film to solve problems such as particle aggregation, irregular arrangement, and voids, thereby reducing costs and improving production efficiency. Summary of the Invention

[0008] To address the aforementioned problems, the present invention aims to provide a method for arranging and dispersing conductive particles in an ACF (Anoxic Coating Fluoride) film. This invention combines rollers and vacuum adsorption, reducing costs, improving production efficiency, and solving the problems of conductive particle aggregation, uneven arrangement, and voids.

[0009] To achieve the above objectives, the present invention adopts the following technical solution: A method for arranging and dispersing conductive particles in an ACF film 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 layer (NCF) is laminated onto a film layer containing arrayed conductive particles to form a bilayer anisotropic conductive film.

[0010] Formula for calculating the vacuum adsorption of conductive particles:

[0011]

[0012]

[0013] In some embodiments, at least the outer surface material of the roller is polytetrafluoroethylene (PTFE). Preferably, it is PTFE from the Chemours Teflon® PTFE 857-203 or Whitford Xylan® 1000 series.

[0014] Preferably, the distance between the upper end face of the roller and the lower end face of the adhesive film is within 3 μm.

[0015] Preferably, the adhesive film in step (2) comprises the following components by mass 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, YDF-1011, Huntsman ARALDITE® MY 790-1, and ARALDITE® GY285; 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 DOW Paraloid_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.

[0016] In some embodiments, the hole is a tapered hole with a taper of 15 to 30 degrees or a through hole, and the diameter of the hole is 1 / 2 to 1 / 3 of the diameter of the conductive particle.

[0017] In some embodiments, the distance between adjacent holes is 1 / 2 to 3 / 2 times the diameter of the conductive particle.

[0018] In some embodiments, the pores can adsorb conductive particles with a particle size of 1 to 20 μm, and the specific gravity of the conductive particles is 1 to 9.

[0019] In some embodiments, the tapered holes form one or more patterns. The patterns are determined for different chip pins in the application. These patterns include triangles, circles, squares, rectangles, hexagons, octagons, cones, ellipses, etc.

[0020] Preferably, the non-conductive NCF layer comprises the following components by mass 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, YDF-1011, Huntsman ARALDITE® MY 790-1, and ARALDITE® GY285; 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 DOW Paraloid_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.

[0021] Compared with the prior art, the present invention has the following beneficial effects: This invention combines rollers and vacuum adsorption, which reduces costs, improves production efficiency, and solves the problems of conductive particle aggregation, uneven arrangement, and voids.

[0022] When conductive particles are smaller than the specified size, the small-sized conductive particles can be drawn into the roller and re-adsorbed to the normal-sized conductive particles, which will then be coated onto the roller and transferred to the adhesive film without creating voids or having conductive particles smaller than the specified size on the adhesive film.

[0023] Compared with existing technologies that first adsorb particles and then move them onto the film for injection coating, the present invention uses a roller adsorption transfer method where the roller speed is the same as the film movement speed, thus eliminating problems such as uneven arrangement and voids. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the present invention, in which conductive particles are arranged and dispersed in an ACF film; Figure 2 This is a schematic diagram of the conical hole structure in this invention; Figure 3 This is a schematic diagram of the structure of the vacuum adsorption roller of the present invention; Figure 4 This is a schematic diagram of the structure of the roller in this invention; Figure 5 This is a schematic diagram of the pattern arrangement (triangles) on the roller in this invention; Figure 6 This is a schematic diagram of the pattern arrangement (circular) on the roller in this invention; Figure 7 This is a schematic diagram of the pattern arrangement (squares and rectangles) on the roller in this invention; Figure 8 This is a schematic diagram of the pattern arrangement (hexagons) on the roller in this invention; Figure 9 This is a schematic diagram of the adhesive film's adsorption force under different distances between the adhesive film and the roller; Figure 10 This is an electron microscope schematic diagram of the ACF film after transfer printing using a roller with a stainless steel surface. Figure 11 This is an electron microscope schematic diagram of the ACF film after transfer printing using a roller with a polytetrafluoroethylene surface. Figure 12 This is an electron microscope schematic diagram of the ACF film prepared in Comparative Example 1. Figure 13 This is an electron microscope schematic diagram of the ACF film prepared in Comparative Example 2. Figure 14 This is an electron microscope schematic diagram of the ACF film prepared in Example 1. Detailed Implementation

[0025] The present invention will be further described below with reference to embodiments. However, it should be noted that the embodiments do not constitute a limitation on the scope of protection of the present invention.

[0026] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0027] The present invention will be further described below with reference to specific embodiments, but the embodiments do not limit the present invention in any way. Unless otherwise specified, the reagents and instruments used in the embodiments are all commercially available conventional products. Unless otherwise specified, the experimental methods used in the embodiments are all conventional experimental methods or techniques in the art.

[0028] like Figure 1-4 As shown, an embodiment of the present invention provides a method for arranging and dispersing conductive particles in an ACF film, comprising the following steps: (1) Preparation of vacuum adsorption roller; The vacuum adsorption roller includes a roller 1, a plurality of holes 2 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. In this embodiment of the invention, the roller can be made entirely of polytetrafluoroethylene (PTFE), or it can be made of other materials but coated with PTFE, preferably Chemours Teflon® PTFE 857-203 or Whitford Xylan® 1000 series PTFE. Figure 1 , 3 As shown, hole 2 penetrates both the inner and outer sides of the cylindrical sidewall of the drum. Regardless of whether the drum sidewall has one or more layers of material, the hole must penetrate both the inner and outer sides. A vacuum pump can connect to the interior of the drum from the center of the bottom surface of the cylinder, as shown... Figure 3 As shown.

[0029] In an embodiment of the invention, the holes on the roller are created using a femtosecond laser. The pulse duration is extremely short (1 femtosecond = 10^6). - ¹ 5 In seconds, energy is deposited and material is removed before the roller material can conduct heat, resulting in almost no thermal melting, recast layers, or microcracks, achieving "cold working." This makes the machining edges extremely sharp, allowing for precise control of the removed area, thus creating well-defined micropores without changes in hole size over time.

[0030] (2) Adsorption and transfer of conductive particles; Turn on the vacuum pump and maintain a vacuum level of 10 inside the drum. 4 ~10 6Pa causes conductive particles 3 to be adsorbed onto the holes 2; when the roller rolls, a layer of adhesive film 4 with a viscosity greater than or equal to the vacuum adsorption force moves synchronously with the roller, adhering the conductive particles to the adhesive film to form an adhesive film layer containing arrayed conductive particles. (3) Film lamination: A non-conductive layer (NCF) is laminated onto a film layer containing arrayed conductive particles to form a bilayer anisotropic conductive film.

[0031] Formula for calculating the vacuum adsorption of conductive particles:

[0032]

[0033] Preferably, the distance between the upper end face of the roller and the lower end face of the adhesive film is within 3 μm.

[0034] In an embodiment of the present invention, the adhesive film in step (2) comprises the following components by mass 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, YDF-1011, 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 DOW Paraloid_BTA-751 and TMS-2670; and the latent curing agent is Asahi Kasei HX-3941 or HX-3088.

[0035] 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.

[0036] The solvent is one or a combination of butanone, toluene, ethyl acetate, and propylene glycol methyl ether acetate.

[0037] In some embodiments, the hole is a tapered hole with a taper of 15 to 30 degrees or a through hole, such as... Figure 2-3 As shown, the aperture of the hole is 1 / 2 to 1 / 3 of the diameter of the conductive particle.

[0038] In some embodiments, the distance between adjacent holes is 1 / 2 to 3 / 2 times the diameter of the conductive particle.

[0039] In some embodiments, the conical pores can adsorb conductive particles with a particle size of 1 to 20 μm and a specific gravity of 1 to 9.

[0040] In some embodiments, the conical holes form one or more patterns. These patterns include triangles, circles, squares, rectangles, hexagons, octagons, cones, ellipses, etc. Figures 5-8 As shown.

[0041] The non-conductive NCF layer can employ any of the existing non-conductive NCF technologies. In embodiments of the present invention, 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, YDF-1011, 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.

[0042] 1. Optimal distance between adhesive film and roller Figure 4 This is a schematic diagram showing the adhesive film's adsorption force under different distances between the film and the roller. From... Figure 9 It can be seen that the greater the distance, the weaker the adsorption force. Therefore, the optimal distance between the adhesive film and the roller is 1 / 2 to 1 / 4 of the diameter of the conductive particles.

[0043] II. Research on the Surface Material of the Roller Table 1 Performance data of different roller materials

[0044] Based on the advantages and disadvantages of roller materials in Table 1, stainless steel and polytetrafluoroethylene were selected as roller materials and applied to the embodiments of the present invention.

[0045] A roller with a stainless steel surface is selected. Conductive particles adhere to the roller surface, causing the aggregated particles to transfer onto the adhesive film. Figure 10 As shown.

[0046] The rollers selected have a surface made of polytetrafluoroethylene (PTFE), and their surface is free of adhering particles. After the transfer to the adhesive film, no agglomeration was observed. Figure 11 As shown.

[0047] III. Study on the relationship between roller vacuum adsorption force and adhesive film adhesion Table 2 shows the performance ratio of roller vacuum adsorption force to adhesive film adhesion.

[0048] Table 2 shows the required ratio of adsorption capacity to adhesive film adhesion to achieve the desired transfer capacity of the particles.

[0049] IV. Study on Roller Rotation Speed ​​and Film Movement Speed When the roller rotation speed and the film movement speed are mismatched, particle alignment displacement can easily occur. To verify the effect of roller rotation speed on the conductive particle alignment effect in the method of this invention, and to determine the optimal process window, the following Example 1 and Comparative Examples 1-2 are compared and analyzed: Example 1 (Medium Speed) Implementation conditions: Optimize the drum speed to 15 rpm.

[0050] Results: At this rotation speed, the rotation of the roller achieves a dynamic balance with the vacuum adsorption and particle transfer process. On 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 between the film and the particles is just right, achieving nearly 100% complete and orderly transfer. The final ACF film has highly regular single-layer, array-like distribution of conductive particles, with uniform particle spacing and no aggregation or missing particles. Figure 14 As shown.

[0051] Comparative Example 1 (Low Speed) Implementation conditions: Control the drum speed at 1 rpm.

[0052] Effect: Due to the excessively slow rotation speed, the time it takes for the roller to pass through the adhesive film per unit area is too long. This results in the conductive particles on individual conical holes being in prolonged contact and being pulled by the adhesive layer of the film. Some particles shift or flip when they detach from the holes, disrupting the intended array order. The final adhesive film layer exhibits uneven distribution of conductive particles, with localized aggregation and gaps, resulting in poor particle array regularity. Figure 12 As shown.

[0053] Comparative Example 2 (High Speed) Implementation conditions: Increase the drum speed to 80 rpm.

[0054] Results: Due to the excessively high rotation speed, the vacuum adsorption system did not have enough time to fill each of the conical holes it passed through, resulting in "insufficient adsorption." Simultaneously, the contact time between the adhesive film and the roller was too short, causing some adsorbed particles to fail to be effectively and completely transferred to the adhesive film, significantly reducing the transfer rate. The resulting adhesive film layer has a low density of conductive particles and contains numerous unfilled blank areas, making it impossible to guarantee a reliable circuit connection. Figure 13 As shown.

[0055] To quantify the above effects, we conducted performance tests on ACF film samples prepared at different rotation speeds, and the results are shown in Table 3 below: Table 3. Performance test results of ACF films prepared in Example 1 and Comparative Examples 1-2 at different rotation speeds.

[0056] Only within the preferred medium rotational speed range (5-35 rpm) of this invention can a high-density, highly uniform conductive particle array be obtained simultaneously, thereby achieving excellent conductive anisotropy.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

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 layer (NCF) is laminated onto an adhesive film layer containing arrayed conductive particles to form a bilayer anisotropic conductive adhesive film.

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 distance between the upper end face of the roller and the lower end face of the adhesive film is within 3 μm.

4. 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, YDF-1011, 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 DOW Paraloid_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.

5. The method for arranging and dispersing conductive particles in an ACF film according to claim 1, characterized in that, 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 diameter of the conductive particle.

6. 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.

7. 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.

8. 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.

9. The method for arranging and dispersing conductive particles in an ACF film according to claim 1, characterized in that, The patterns include triangles, circles, squares, rectangles, hexagons, octagons, cones, and ellipses.

10. 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, YDF-1011, 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 DOW Paraloid_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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